EC 1.1.1.22     
Accepted name: UDP-glucose 6-dehydrogenase
Reaction: UDP-α-D-glucose + 2 NAD+ + H2O = UDP-α-D-glucuronate + 2 NADH + 2 H+
Other name(s): UDP-glucose dehydrogenase; uridine diphosphoglucose dehydrogenase; UDPG dehydrogenase; UDPG:NAD oxidoreductase; UDP-α-D-glucose:NAD oxidoreductase; UDP-glucose:NAD+ oxidoreductase; uridine diphosphate glucose dehydrogenase; UDP-D-glucose dehydrogenase; uridine diphosphate D-glucose dehydrogenase
Systematic name: UDP-α-D-glucose:NAD+ 6-oxidoreductase
Comments: Also acts on UDP-α-D-2-deoxyglucose.
References:
1.  Druzhinina, T.N., Kusov, Y.Y., Shibaev, V.N., Kochetkov, N.K., Biely, P., Kucar, S. and Bauer, S. Uridine diphosphate 2-deoxyglucose. Chemical synthesis, enzymic oxidation and epimerization. Biochim. Biophys. Acta 381 (1975) 301–307. [PMID: 1091296]
2.  Maxwell, E.S., Kalckar, H.M. and Strominger, J.L. Some properties of uridine diphosphoglucose dehydrogenase. Arch. Biochem. Biophys. 65 (1956) 2–10. [PMID: 13373402]
3.  Strominger, J.L. and Mapson, L.W. Uridine diphosphoglucose dehydrogenase of pea seedlings. Biochem. J. 66 (1957) 567–572. [PMID: 13459898]
4.  Strominger, J.L., Maxwell, E.S., Axelrod, J. and Kalckar, H.M. Enzymatic formation of uridine diphosphogluconic acid. J. Biol. Chem. 224 (1957) 79–90. [PMID: 13398389]
[EC 1.1.1.22 created 1961]
 
 
EC 1.1.1.48     
Accepted name: D-galactose 1-dehydrogenase
Reaction: D-galactose + NAD+ = D-galactono-1,4-lactone + NADH + H+
Other name(s): D-galactose dehydrogenase; β-galactose dehydrogenase (ambiguous); NAD+-dependent D-galactose dehydrogenase
Systematic name: D-galactose:NAD+ 1-oxidoreductase
Comments: This enzyme is part of the De Ley-Doudoroff pathway, which is used by some bacteria during growth on D-galactose.
References:
1.  De Ley, J. and Doudoroff, M. The metabolism of D-galactose in Pseudomonas saccharophila. J. Biol. Chem. 227 (1957) 745–757. [PMID: 13462997]
2.  Hu, A.S.L. and Cline, A.L. The regulation of some sugar dehydrogenases in a pseudomonad. Biochim. Biophys. Acta 93 (1964) 237–245. [PMID: 14251301]
[EC 1.1.1.48 created 1961, modified 2011]
 
 
EC 1.1.1.117     
Accepted name: D-arabinose 1-dehydrogenase [NAD(P)+]
Reaction: D-arabinose + NAD(P)+ = D-arabinono-1,4-lactone + NAD(P)H + H+
Other name(s): D-arabinose 1-dehydrogenase [NAD(P)]
Systematic name: D-arabinose:NAD(P)+ 1-oxidoreductase
Comments: Also acts on L-galactose, 6-deoxy- and 3,6-dideoxy-L-galactose.
References:
1.  Cline, A.L. and Hu, A.S.L. The isolation of three sugar dehydrogenases from a psuedomonad. J. Biol. Chem. 240 (1965) 4488–4492. [PMID: 5845847]
2.  Cline, A.L. and Hu, A.S.L. Enzymatic characterization and comparison of three sugar dehydrogenases from a pseudomonad. J. Biol. Chem. 240 (1965) 4493–4497. [PMID: 5845848]
3.  Cline, A.L. and Hu, A.S.L. Some physical properties of three sugar dehydrogenases from a pseudomonad. J. Biol. Chem. 240 (1965) 4498–4502. [PMID: 5845849]
[EC 1.1.1.117 created 1972]
 
 
EC 1.1.1.120     
Accepted name: galactose 1-dehydrogenase (NADP+)
Reaction: D-galactose + NADP+ = D-galactono-1,5-lactone + NADPH + H+
Other name(s): D-galactose dehydrogenase (NADP+); galactose 1-dehydrogenase (NADP)
Systematic name: D-galactose:NADP+ 1-oxidoreductase
Comments: Also acts on L-arabinose, 6-deoxy- and 2-deoxy-D-galactose.
References:
1.  Cline, A.L. and Hu, A.S.L. The isolation of three sugar dehydrogenases from a psuedomonad. J. Biol. Chem. 240 (1965) 4488–4492. [PMID: 5845847]
2.  Cline, A.L. and Hu, A.S.L. Enzymatic characterization and comparison of three sugar dehydrogenases from a pseudomonad. J. Biol. Chem. 240 (1965) 4493–4497. [PMID: 5845848]
3.  Cline, A.L. and Hu, A.S.L. Some physical properties of three sugar dehydrogenases from a pseudomonad. J. Biol. Chem. 240 (1965) 4498–4502. [PMID: 5845849]
4.  Schiwara, H.W. and Domagk, G.F. Über den Abbau der Desoxyzucker durch Bakterienenzyme. V. Anreicherung und Charakterisierung einer NADP-abhängigen Abequosedehydrogenase aus Pseudomonas putida. Hoppe-Seyler's Z. Physiol. Chem. 349 (1968) 1321–1329. [PMID: 4387016]
[EC 1.1.1.120 created 1972]
 
 
EC 1.1.1.121     
Accepted name: aldose 1-dehydrogenase (NAD+)
Reaction: D-aldose + NAD+ = D-aldonolactone + NADH + H+
Other name(s): aldose dehydrogenase; D-aldohexose dehydrogenase; aldose 1-dehydrogenase
Systematic name: D-aldose:NAD+ 1-oxidoreductase
Comments: Acts on D-glucose, 2-deoxy- and 6-deoxy-D-glucose, D-galactose, 6-deoxy-D-galactose, 2-deoxy-L-arabinose and D-xylose.
References:
1.  Cline, A.L. and Hu, A.S.L. The isolation of three sugar dehydrogenases from a psuedomonad. J. Biol. Chem. 240 (1965) 4488–4492. [PMID: 5845847]
2.  Cline, A.L. and Hu, A.S.L. Enzymatic characterization and comparison of three sugar dehydrogenases from a pseudomonad. J. Biol. Chem. 240 (1965) 4493–4497. [PMID: 5845848]
3.  Cline, A.L. and Hu, A.S.L. Some physical properties of three sugar dehydrogenases from a pseudomonad. J. Biol. Chem. 240 (1965) 4498–4502. [PMID: 5845849]
[EC 1.1.1.121 created 1972]
 
 
EC 1.1.1.186     
Accepted name: dTDP-galactose 6-dehydrogenase
Reaction: dTDP-D-galactose + 2 NADP+ + H2O = dTDP-D-galacturonate + 2 NADPH + 2 H+
Other name(s): thymidine-diphosphate-galactose dehydrogenase
Systematic name: dTDP-D-galactose:NADP+ 6-oxidoreductase
References:
1.  Katan, R. and Avigad, G. NADP dependent oxidation of TDP-glucose by an enzyme system from sugar beets. Biochem. Biophys. Res. Commun. 24 (1966) 18–24. [PMID: 4381717]
[EC 1.1.1.186 created 1984, modified 2002]
 
 
EC 1.1.1.200     
Accepted name: aldose-6-phosphate reductase (NADPH)
Reaction: D-sorbitol 6-phosphate + NADP+ = D-glucose 6-phosphate + NADPH + H+
Other name(s): aldose 6-phosphate reductase; NADP-dependent aldose 6-phosphate reductase; A6PR; aldose-6-P reductase; aldose-6-phosphate reductase; alditol 6-phosphate:NADP 1-oxidoreductase; aldose-6-phosphate reductase (NADPH2)
Systematic name: D-aldose-6-phosphate:NADP+ 1-oxidoreductase
Comments: In the reverse reaction, acts also on D-galactose 6-phosphate and, more slowly, on D-mannose 6-phosphate and 2-deoxy-D-glucose 6-phosphate.
References:
1.  Negm, F.B. and Loescher, W.H. Characterization and partial-purification of aldose-6-phosphate reductase (alditol-6-phosphate-NADP 1-oxidoreductase) from apple leaves. Plant Physiol. 67 (1981) 139–142. [PMID: 16661614]
[EC 1.1.1.200 created 1984]
 
 
EC 1.1.1.316     
Accepted name: L-galactose 1-dehydrogenase
Reaction: L-galactose + NAD+ = L-galactono-1,4-lactone + NADH + H+
Other name(s): L-GalDH; L-galactose dehydrogenase
Systematic name: L-galactose:NAD+ 1-oxidoreductase
Comments: The enzyme catalyses a step in the ascorbate biosynthesis in higher plants (Smirnoff-Wheeler pathway). The activity with NADP+ is less than 10% of the activity with NAD+.
References:
1.  Mieda, T., Yabuta, Y., Rapolu, M., Motoki, T., Takeda, T., Yoshimura, K., Ishikawa, T. and Shigeoka, S. Feedback inhibition of spinach L-galactose dehydrogenase by L-ascorbate. Plant Cell Physiol. 45 (2004) 1271–1279. [PMID: 15509850]
2.  Gatzek, S., Wheeler, G.L. and Smirnoff, N. Antisense suppression of L-galactose dehydrogenase in Arabidopsis thaliana provides evidence for its role in ascorbate synthesis and reveals light modulated L-galactose synthesis. Plant J. 30 (2002) 541–553. [PMID: 12047629]
3.  Wheeler, G.L., Jones, M.A. and Smirnoff, N. The biosynthetic pathway of vitamin C in higher plants. Nature 393 (1998) 365–369. [PMID: 9620799]
4.  Oh, M.M., Carey, E.E. and Rajashekar, C.B. Environmental stresses induce health-promoting phytochemicals in lettuce. Plant Physiol. Biochem. 47 (2009) 578–583. [PMID: 19297184]
[EC 1.1.1.316 created 2011]
 
 
EC 1.1.1.341     
Accepted name: CDP-abequose synthase
Reaction: CDP-α-D-abequose + NADP+ = CDP-4-dehydro-3,6-dideoxy-α-D-glucose + NADPH + H+
Glossary: CDP-α-D-abequose = CDP-3,6-dideoxy-α-D-xylo-hexose
Other name(s): rfbJ (gene name)
Systematic name: CDP-α-D-abequose:NADP+ 4-oxidoreductase
Comments: Isolated from Yersinia pseudotuberculosis [1,3] and Salmonella enterica [1,2].
References:
1.  Kessler, A.C., Brown, P.K., Romana, L.K. and Reeves, P.R. Molecular cloning and genetic characterization of the rfb region from Yersinia pseudotuberculosis serogroup IIA, which determines the formation of the 3,6-dideoxyhexose abequose. J. Gen. Microbiol. 137 (1991) 2689–2695. [PMID: 1724263]
2.  Wyk, P. and Reeves, P. Identification and sequence of the gene for abequose synthase, which confers antigenic specificity on group B salmonellae: homology with galactose epimerase. J. Bacteriol. 171 (1989) 5687–5693. [PMID: 2793832]
3.  Thorson, J.S., Lo, S.F., Ploux, O., He, X. and Liu, H.W. Studies of the biosynthesis of 3,6-dideoxyhexoses: molecular cloning and characterization of the asc (ascarylose) region from Yersinia pseudotuberculosis serogroup VA. J. Bacteriol. 176 (1994) 5483–5493. [PMID: 8071227]
[EC 1.1.1.341 created 2012]
 
 
EC 1.1.1.359     
Accepted name: aldose 1-dehydrogenase [NAD(P)+]
Reaction: an aldopyranose + NAD(P)+ = an aldono-1,5-lactone + NAD(P)H + H+
Systematic name: an aldopyranose:NAD(P)+ 1-oxidoreductase
Comments: The enzyme from the archaeon Sulfolobus solfataricus shows broad specificity towards aldoses (D-glucose, D-galactose, D-xylose, L-arabinose, 6-deoxy-D-glucose, D-fucose) and can utilize NAD+ and NADP+ with similar catalytic efficiency. It is involved in aldose catabolism via the branched variant of the Entner-Doudoroff pathway.
References:
1.  Giardina, P., de Biasi, M.G., de Rosa, M., Gambacorta, A. and Buonocore, V. Glucose dehydrogenase from the thermoacidophilic archaebacterium Sulfolobus solfataricus. Biochem. J. 239 (1986) 517–522. [PMID: 3827812]
2.  Smith, L.D., Budgen, N., Bungard, S.J., Danson, M.J. and Hough, D.W. Purification and characterization of glucose dehydrogenase from the thermoacidophilic archaebacterium Thermoplasma acidophilum. Biochem. J. 261 (1989) 973–977. [PMID: 2803257]
3.  Lamble, H.J., Heyer, N.I., Bull, S.D., Hough, D.W. and Danson, M.J. Metabolic pathway promiscuity in the archaeon Sulfolobus solfataricus revealed by studies on glucose dehydrogenase and 2-keto-3-deoxygluconate aldolase. J. Biol. Chem. 278 (2003) 34066–34072. [PMID: 12824170]
4.  Theodossis, A., Milburn, C.C., Heyer, N.I., Lamble, H.J., Hough, D.W., Danson, M.J. and Taylor, G.L. Preliminary crystallographic studies of glucose dehydrogenase from the promiscuous Entner-Doudoroff pathway in the hyperthermophilic archaeon Sulfolobus solfataricus. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 61 (2005) 112–115. [PMID: 16508107]
5.  Milburn, C.C., Lamble, H.J., Theodossis, A., Bull, S.D., Hough, D.W., Danson, M.J. and Taylor, G.L. The structural basis of substrate promiscuity in glucose dehydrogenase from the hyperthermophilic archaeon Sulfolobus solfataricus. J. Biol. Chem. 281 (2006) 14796–14804. [PMID: 16556607]
6.  Haferkamp, P., Kutschki, S., Treichel, J., Hemeda, H., Sewczyk, K., Hoffmann, D., Zaparty, M. and Siebers, B. An additional glucose dehydrogenase from Sulfolobus solfataricus: fine-tuning of sugar degradation. Biochem. Soc. Trans. 39 (2011) 77–81. [PMID: 21265750]
[EC 1.1.1.359 created 2013]
 
 
EC 1.1.1.360     
Accepted name: glucose/galactose 1-dehydrogenase
Reaction: (1) D-glucopyranose + NADP+ = D-glucono-1,5-lactone + NADPH + H+
(2) D-galactopyranose + NADP+ = D-galactono-1,5-lactone + NADPH + H+
Other name(s): GdhA; dual-specific glucose/galactose dehydrogenase; glucose (galactose) dehydrogenase; glucose/galactose dehydrogenase
Systematic name: D-glucose/D-galactose 1-dehydrogenase (NADPH)
Comments: A zinc protein. The enzyme from the archaeon Picrophilus torridus is involved in glucose and galactose catabolism via the nonphosphorylative variant of the Entner-Doudoroff pathway. It shows 20-fold higher activity with NADP+ compared to NAD+. The oxidation of D-glucose and D-galactose is catalysed at a comparable rate (cf. EC 1.1.1.119, glucose 1-dehydrogenase (NADP+) and EC 1.1.1.120, galactose 1-dehydrogenase (NADP+)).
References:
1.  Angelov, A., Futterer, O., Valerius, O., Braus, G.H. and Liebl, W. Properties of the recombinant glucose/galactose dehydrogenase from the extreme thermoacidophile, Picrophilus torridus. FEBS J. 272 (2005) 1054–1062. [PMID: 15691337]
2.  Milburn, C.C., Lamble, H.J., Theodossis, A., Bull, S.D., Hough, D.W., Danson, M.J. and Taylor, G.L. The structural basis of substrate promiscuity in glucose dehydrogenase from the hyperthermophilic archaeon Sulfolobus solfataricus. J. Biol. Chem. 281 (2006) 14796–14804. [PMID: 16556607]
[EC 1.1.1.360 created 2013]
 
 
EC 1.1.1.376     
Accepted name: L-arabinose 1-dehydrogenase [NAD(P)+]
Reaction: α-L-arabinopyranose + NAD(P)+ = L-arabinono-1,4-lactone + NAD(P)H + H+
Other name(s): L-arabino-aldose dehydrogenase
Systematic name: α-L-arabinopyranose:NAD(P)+ 1-oxidoreductase
Comments: The enzymes from the bacterium Azospirillum brasilense and the archaeon Haloferax volcanii are part of the L-arabinose degradation pathway and prefer NADP+ over NAD+. In vitro the enzyme from Azospirillum brasilense shows also high catalytic efficiency with D-galactose. The enzyme is specific for α-L-arabinopyranose [3,4].
References:
1.  Novick, N.J. and Tyler, M.E. Partial purification and properties of an L-arabinose dehydrogenase from Azospirillum brasilense. Can. J. Microbiol. 29 (1983) 242–246.
2.  Watanabe, S., Kodaki, T. and Makino, K. Cloning, expression, and characterization of bacterial L-arabinose 1-dehydrogenase involved in an alternative pathway of L-arabinose metabolism. J. Biol. Chem. 281 (2006) 2612–2623. [PMID: 16326697]
3.  Johnsen, U., Sutter, J.M., Zaiss, H. and Schonheit, P. L-Arabinose degradation pathway in the haloarchaeon Haloferax volcanii involves a novel type of L-arabinose dehydrogenase. Extremophiles 17 (2013) 897–909. [PMID: 23949136]
4.  Aro-Karkkainen, N., Toivari, M., Maaheimo, H., Ylilauri, M., Pentikainen, O.T., Andberg, M., Oja, M., Penttila, M., Wiebe, M.G., Ruohonen, L. and Koivula, A. L-arabinose/D-galactose 1-dehydrogenase of Rhizobium leguminosarum bv. trifolii characterised and applied for bioconversion of L-arabinose to L-arabonate with Saccharomyces cerevisiae. Appl. Microbiol. Biotechnol. 98 (2014) 9653–9665. [PMID: 25236800]
[EC 1.1.1.376 created 2014, modified 2022]
 
 
EC 1.1.1.389     
Accepted name: 2-dehydro-3-deoxy-L-galactonate 5-dehydrogenase
Reaction: 2-dehydro-3-deoxy-L-galactonate + NAD+ = 3-deoxy-D-glycero-2,5-hexodiulosonate + NADH + H+
Systematic name: 2-dehydro-3-deoxy-L-galactonate:NAD+ 5-oxidoreductase
Comments: The enzyme, characterized from agarose-degrading bacteria, is involved in a degradation pathway for 3,6-anhydro-α-L-galactopyranose, a major component of the polysaccharides of red macroalgae.
References:
1.  Lee, S.B., Cho, S.J., Kim, J.A., Lee, S.Y., Kim, S.M. and Lim, H.S. Metabolic pathway of 3,6-anhydro-L-galactose in agar-degrading microorganisms. Biotechnol. Bioprocess Eng. 19 (2014) 866–878.
[EC 1.1.1.389 created 2015]
 
 
EC 1.1.1.414     
Accepted name: L-galactonate 5-dehydrogenase
Reaction: L-galactonate + NAD+ = D-tagaturonate + NADH + H+
Other name(s): lgoD (gene name); lgaC (gene name)
Systematic name: L-galactonate:NAD+ 5-oxidoreductase
Comments: The enzyme, reported from the human gut bacteria Escherichia coli and Bacteroides vulgatus, participates in an L-galactonate degradation pathway.
References:
1.  Cooper, R.A. The pathway for L-galactonate catabolism in Escherichia coli K-12. FEBS Lett. 103 (1979) 216–220. [PMID: 381020]
2.  Kuivanen, J. and Richard, P. The yjjN of E. coli codes for an L-galactonate dehydrogenase and can be used for quantification of L-galactonate and L-gulonate. Appl. Biochem. Biotechnol. 173 (2014) 1829–1835. [PMID: 24861318]
3.  Hobbs, M.E., Williams, H.J., Hillerich, B., Almo, S.C. and Raushel, F.M. L-Galactose metabolism in Bacteroides vulgatus from the human gut microbiota. Biochemistry 53 (2014) 4661–4670. [PMID: 24963813]
[EC 1.1.1.414 created 2018]
 
 
EC 1.1.1.431     
Accepted name: D-xylose reductase (NADPH)
Reaction: xylitol + NADP+ = D-xylose + NADPH + H+
Other name(s): XYL1 (gene name, ambiguous); xyl1 (gene name, ambiguous); xyrA (gene name); xyrB (gene name)
Systematic name: xylitol:NADP+ oxidoreductase
Comments: Xylose reductases catalyse the reduction of xylose to xylitol, the initial reaction in the fungal D-xylose degradation pathway. Most of the enzymes exhibit a strict requirement for NADPH (e.g. the enzymes from Saccharomyces cerevisiae, Aspergillus niger, Trichoderma reesei, Candida tropicalis, Saitozyma flava, and Candida intermedia). Some D-xylose reductases have dual coenzyme specificity, though they still prefer NADPH to NADH (cf. EC 1.1.1.307, D-xylose reductase [NAD(P)H]). Very rarely the enzyme prefers NADH (cf. EC 1.1.1.430, D-xylose reductase (NADH)).
References:
1.  Bolen, P.L. and Detroy, R.W. Induction of NADPH-linked D-xylose reductase and NAD-linked xylitol dehydrogenase activities in Pachysolen tannophilus by D-xylose, L-arabinose, or D-galactose. Biotechnol. Bioeng. 27 (1985) 302–307. [PMID: 18553673]
2.  Suzuki, T., Yokoyama, S., Kinoshita, Y., Yamada, H., Hatsu, M., Takamizawa, K. and Kawai, K. Expression of xyrA gene encoding for D-xylose reductase of Candida tropicalis and production of xylitol in Escherichia coli. J. Biosci. Bioeng. 87 (1999) 280–284. [PMID: 16232468]
3.  Nidetzky, B., Mayr, P., Hadwiger, P. and Stutz, A.E. Binding energy and specificity in the catalytic mechanism of yeast aldose reductases. Biochem. J. 344 Pt 1 (1999) 101–107. [PMID: 10548539]
4.  Mayr, P., Bruggler, K., Kulbe, K.D. and Nidetzky, B. D-Xylose metabolism by Candida intermedia: isolation and characterisation of two forms of aldose reductase with different coenzyme specificities. J. Chromatogr. B Biomed. Sci. Appl. 737 (2000) 195–202. [PMID: 10681056]
5.  Sene, L., Felipe, M.G., Silva, S.S. and Vitolo, M. Preliminary kinetic characterization of xylose reductase and xylitol dehydrogenase extracted from Candida guilliermondii FTI 20037 cultivated in sugarcane bagasse hydrolysate for xylitol production. Appl. Biochem. Biotechnol. 91-93 (2001) 671–680. [PMID: 11963895]
6.  Jeong, E.Y., Sopher, C., Kim, I.S. and Lee, H. Mutational study of the role of tyrosine-49 in the Saccharomyces cerevisiae xylose reductase. Yeast 18 (2001) 1081–1089. [PMID: 11481678]
7.  Chroumpi, T., Peng, M., Aguilar-Pontes, M.V., Muller, A., Wang, M., Yan, J., Lipzen, A., Ng, V., Grigoriev, I.V., Makela, M.R. and de Vries, R.P. Revisiting a ‘simple’ fungal metabolic pathway reveals redundancy, complexity and diversity. Microb. Biotechnol. 14 (2021) 2525–2537. [PMID: 33666344]
8.  Terebieniec, A., Chroumpi, T., Dilokpimol, A., Aguilar-Pontes, M.V., Makela, M.R. and de Vries, R.P. Characterization of D-xylose reductase, XyrB, from Aspergillus niger. Biotechnol Rep (Amst) 30:e00610 (2021). [PMID: 33842213]
[EC 1.1.1.431 created 2022]
 
 
EC 1.1.2.11     
Accepted name: glucoside 3-dehydrogenase (cytochrome c)
Reaction: a D-glucoside + a ferric c-type cytochrome = a 3-dehydro-D-glucoside + a ferrous c-type cytochrome
Other name(s): D-glucoside 3-dehydrogenase (ambiguous); D-aldohexopyranoside dehydrogenase (ambiguous); D-aldohexoside:cytochrome c oxidoreductase; hexopyranoside-cytochrome c oxidoreductase
Systematic name: a D-glucoside:ferric c-type cytochrome 3-oxidoreductase
Comments: This bacterial enzyme acts on D-glucose, D-galactose, D-glucosides and D-galactosides, but the best substrates are disaccharides with a glucose moiety at the non-reducing end. It consists of two subunits, a catalytic subunit that contains an FAD cofactor and an iron-sulfur cluster, and a "hitch-hiker" subunit containing a signal peptide for translocation into the periplasm. A dedicated c-type cytochrome protein serves as an electron acceptor, transferring the electrons from the catalytic subunit to the cell's electron transfer chain. cf. EC 1.1.99.13, glucoside 3-dehydrogenase (acceptor).
References:
1.  Hayano, K. and Fukui, S. Purification and properties of 3-ketosucrose-forming enzyme from the cells of Agrobacterium tumefaciens. J. Biol. Chem. 242 (1967) 3665–3672. [PMID: 6038493]
2.  Nakamura, L.K. and Tyler, D.D. Induction of D-aldohexoside:cytochrome c oxidoreductase in Agrobacterium tumefaciens. J. Bacteriol. 129 (1977) 830–835. [PMID: 838689]
3.  Takeuchi, M., Ninomiya, K., Kawabata, K., Asano, N., Kameda, Y. and Matsui, K. Purification and properties of glucoside 3-dehydrogenase from Flavobacterium saccharophilum. J. Biochem. 100 (1986) 1049–1055. [PMID: 3818559]
4.  Takeuchi, M., Asano, N., Kameda, Y. and Matsui, K. Physiological role of glucoside 3-dehydrogenase and cytochrome c551 in the sugar oxidizing system of Flavobacterium saccharophilum. J. Biochem. 103 (1988) 938–943. [PMID: 2844746]
5.  Tsugawa, W., Horiuchi, S., Tanaka, M., Wake, H. and Sode, K. Purification of a marine bacterial glucose dehydrogenase from Cytophaga marinoflava and its application for measurement of 1,5-anhydro-D-glucitol. Appl. Biochem. Biotechnol. 56 (1996) 301–310. [PMID: 8984902]
6.  Kojima, K., Tsugawa, W. and Sode, K. Cloning and expression of glucose 3-dehydrogenase from Halomonas sp. α-15 in Escherichia coli. Biochem. Biophys. Res. Commun. 282 (2001) 21–27. [PMID: 11263965]
7.  Zhang, J.F., Zheng, Y.G., Xue, Y.P. and Shen, Y.C. Purification and characterization of the glucoside 3-dehydrogenase produced by a newly isolated Stenotrophomonas maltrophilia CCTCC M 204024. Appl. Microbiol. Biotechnol. 71 (2006) 638–645. [PMID: 16292530]
8.  Zhang, J.F., Chen, W.Q. and Chen, H. Gene cloning and expression of a glucoside 3-dehydrogenase from Sphingobacterium faecium ZJF-D6, and used it to produce N-p-nitrophenyl-3-ketovalidamine. World J. Microbiol. Biotechnol. 33:21 (2017). [PMID: 28044272]
9.  Miyazaki, R., Yamazaki, T., Yoshimatsu, K., Kojima, K., Asano, R., Sode, K. and Tsugawa, W. Elucidation of the intra- and inter-molecular electron transfer pathways of glucoside 3-dehydrogenase. Bioelectrochemistry 122 (2018) 115–122. [PMID: 29625423]
[EC 1.1.2.11 created 2022]
 
 
EC 1.1.3.5     
Accepted name: hexose oxidase
Reaction: D-glucose + O2 = D-glucono-1,5-lactone + H2O2
Systematic name: D-hexose:oxygen 1-oxidoreductase
Comments: A copper glycoprotein. Also oxidizes D-galactose, D-mannose, maltose, lactose and cellobiose.
References:
1.  Bean, R.C. and Hassid, W.Z. Carbohydrate oxidase from a red alga Iridophycus flaccidum. J. Biol. Chem. 218 (1956) 425–436. [PMID: 13278350]
2.  Bean, R.C., Porter, G.G. and Steinberg, B.M. Carbohydrate metabolism of citrus fruit. II. Oxidation of sugars by an aerodehydrogenase from young orange fruit. J. Biol. Chem. 236 (1961) 1235–1240. [PMID: 13688220]
3.  Sullivan, J.D. and Ikawa, M. Purification and characterization of hexose oxidase from the red alga Chondrus crispus. Biochim. Biophys. Acta 309 (1973) 11–22. [PMID: 4708670]
[EC 1.1.3.5 created 1961, modified 1976]
 
 
EC 1.1.3.9     
Accepted name: galactose oxidase
Reaction: D-galactose + O2 = D-galacto-hexodialdose + H2O2
Other name(s): D-galactose oxidase; β-galactose oxidase
Systematic name: D-galactose:oxygen 6-oxidoreductase
Comments: A copper protein.
References:
1.  Avigad, G., Amaral, D., Asensio, C. and Horecker, B.L. The D-galactose oxidase of Polyporus circinatus. J. Biol. Chem. 237 (1962) 2736–2743. [PMID: 13863403]
[EC 1.1.3.9 created 1965]
 
 
EC 1.1.3.11     
Accepted name: L-sorbose oxidase
Reaction: L-sorbose + O2 = 5-dehydro-D-fructose + H2O2
Systematic name: L-sorbose:oxygen 5-oxidoreductase
Comments: Also acts on D-glucose, D-galactose and D-xylose, but not on D-fructose. 2,6-Dichloroindophenol can act as acceptor.
References:
1.  Yamada, Y., Iizuka, K., Aida, K. and Uemura, T. Enzymatic studies on the oxidation of sugar and sugar alcohol. 3. Purification and properties of L-sorbose oxidase from Trametes sanguinea. J. Biochem. (Tokyo) 62 (1967) 223–229. [PMID: 5586487]
[EC 1.1.3.11 created 1972]
 
 
EC 1.1.3.13     
Accepted name: alcohol oxidase
Reaction: a primary alcohol + O2 = an aldehyde + H2O2
Other name(s): ethanol oxidase; alcohol:oxygen oxidoreductase
Systematic name: alcohol:oxygen oxidoreductase (H2O2-forming)
Comments: The enzymes from the fungi Candida methanosorbosa and several Basidiomycetes species contain an FAD cofactor [1,3]. The enzyme from the phytopathogenic fungi Colletotrichum graminicola and Colletotrichum gloeosporioides utilize a mononuclear copper-radical mechanism [4]. The enzyme acts on primary alcohols and unsaturated alcohols, and has much lower activity with branched-chain and secondary alcohols.
References:
1.  Janssen, F.W. and Ruelius, H.W. Alcohol oxidase, a flavoprotein from several Basidiomycetes species. Crystallization by fractional precipitation with polyethylene glycol. Biochim. Biophys. Acta 151 (1968) 330–342. [PMID: 5636370]
2.  Nishida, A., Ishihara, T. and Hiroi, T. Studies on enzymes related to lignan biodegradation. Baiomasu Henkan Keikaku Kenkyu Hokoku (1987) 38–59. (in Japanese)
3.  Suye, S. Purification and properties of alcohol oxidase from Candida methanosorbosa M-2003. Curr. Microbiol. 34 (1997) 374–377. [PMID: 9142745]
4.  Yin, D.T., Urresti, S., Lafond, M., Johnston, E.M., Derikvand, F., Ciano, L., Berrin, J.G., Henrissat, B., Walton, P.H., Davies, G.J. and Brumer, H. Structure-function characterization reveals new catalytic diversity in the galactose oxidase and glyoxal oxidase family. Nat. Commun. 6:10197 (2015). [PMID: 26680532]
[EC 1.1.3.13 created 1972]
 
 
EC 1.1.99.18     
Accepted name: cellobiose dehydrogenase (acceptor)
Reaction: cellobiose + acceptor = cellobiono-1,5-lactone + reduced acceptor
Other name(s): cellobiose dehydrogenase; cellobiose oxidoreductase; Phanerochaete chrysosporium cellobiose oxidoreductase; CBOR; cellobiose oxidase; cellobiose:oxygen 1-oxidoreductase; CDH; cellobiose:(acceptor) 1-oxidoreductase
Systematic name: cellobiose:acceptor 1-oxidoreductase
Comments: Also acts, more slowly, on cello-oligosaccharides, lactose and D-glucosyl-1,4-β-D-mannose. The enzyme from the white rot fungus Phanerochaete chrysosporium is unusual in having two redoxin domains, one containing a flavin and the other a protoheme group. It transfers reducing equivalents from cellobiose to two types of redox acceptor: two-electron oxidants, including redox dyes, benzoquinones, and molecular oxygen, and one-electron oxidants, including semiquinone species, iron(II) complexes, and the model acceptor cytochrome c [9]. 2,6-Dichloroindophenol can act as acceptor in vitro.
References:
1.  Coudray, M.-R., Canebascini, G. and Meier, H. Characterization of a cellobiose dehydrogenase in the cellulolytic fungus porotrichum (Chrysosporium) thermophile. Biochem. J. 203 (1982) 277–284. [PMID: 7103940]
2.  Dekker, R.F.H. Induction and characterization of a cellobiose dehydrogenase produced by a species of Monilia. J. Gen. Microbiol. 120 (1980) 309–316.
3.  Dekker, R.F.H. Cellobiose dehydrogenase produced by Monilia sp. Methods Enzymol. 160 (1988) 454–463.
4.  Habu, N., Samejima, M., Dean, J.F. and Eriksson, K.E. Release of the FAD domain from cellobiose oxidase by proteases from cellulolytic cultures of Phanerochaete chrysosporium. FEBS Lett. 327 (1993) 161–164. [PMID: 8392950]
5.  Baminger, U., Subramaniam, S.S., Renganathan, V. and Haltrich, D. Purification and characterization of cellobiose dehydrogenase from the plant pathogen Sclerotium (Athelia) rolfsii. Appl. Environ. Microbiol. 67 (2001) 1766–1774. [PMID: 11282631]
6.  Hallberg, B.M., Henriksson, G., Pettersson, G. and Divne, C. Crystal structure of the flavoprotein domain of the extracellular flavocytochrome cellobiose dehydrogenase. J. Mol. Biol. 315 (2002) 421–434. [PMID: 11786022]
7.  Ayers, A.R., Ayers, S.B. and Eriksson, K.-E. Cellobiose oxidase, purification and partial characterization of a hemoprotein from Sporotrichum pulverulentum. Eur. J. Biochem. 90 (1978) 171–181. [PMID: 710416]
8.  Ayers, A.R. and Eriksson, K.-E. Cellobiose oxidase from Sporotrichum pulverulentum. Methods Enzymol. 89 (1982) 129–135. [PMID: 7144569]
9.  Mason, M.G., Nicholls, P., Divne, C., Hallberg, B.M., Henriksson, G. and Wilson, M.T. The heme domain of cellobiose oxidoreductase: a one-electron reducing system. Biochim. Biophys. Acta 1604 (2003) 47–54. [PMID: 12686420]
[EC 1.1.99.18 created 1983, modified 2002 (EC 1.1.5.1 created 1983, incorporated 2002, EC 1.1.3.25 created 1986, incorporated 2005)]
 
 
EC 1.1.99.28     
Accepted name: glucose-fructose oxidoreductase
Reaction: D-glucose + D-fructose = D-gluconolactone + D-glucitol
Systematic name: D-glucose:D-fructose oxidoreductase
Comments: D-mannose, D-xylose, D-galactose, 2-deoxy-D-glucose and L-arabinose will function as aldose substrates, but with low affinities. The ketose substrate must be in the open-chain form. The apparent affinity for fructose is low, because little of the fructose substrate is in the open-chain form. Xylulose and glycerone (dihydroxyacetone) will replace fructose, but they are poor substrates. The enzyme from Zymomonas mobilis contains tightly bound NADP+.
References:
1.  Zachariou, M. and Scopes, R.K. Glucose-fructose oxidoreductase: a new enzyme isolated from Zymomonas mobilis that is responsible for sorbitol production. J. Bacteriol. 167 (1986) 863–869. [PMID: 3745122]
2.  Hardman, M.J. and Scopes, R.K. The kinetics of glucose-fructose oxidoreductase from Zymomonas mobilis. Eur. J. Biochem. 173 (1988) 203–209. [PMID: 3356190]
3.  Kanagasundaram, V. and Scopes, R.K. Cloning, sequence analysis and expression of the structural gene encoding glucose-fructose oxidoreductase. J. Bacteriol. 174 (1992) 1439–1447. [PMID: 1537789]
[EC 1.1.99.28 created 1999]
 
 
EC 1.1.99.29     
Accepted name: pyranose dehydrogenase (acceptor)
Reaction: (1) a pyranose + acceptor = a pyranos-2-ulose (or a pyranos-3-ulose or a pyranos-2,3-diulose) + reduced acceptor
(2) a pyranoside + acceptor = a pyranosid-3-ulose (or a pyranosid-3,4-diulose) + reduced acceptor
Glossary: ferricenium ion = bis(η5-cyclopentadienyl)iron(1+)
Other name(s): pyranose dehydrogenase; pyranose-quinone oxidoreductase; quinone-dependent pyranose dehydrogenase; PDH
Systematic name: pyranose:acceptor oxidoreductase
Comments: Requires FAD. A number of aldoses and ketoses in pyranose form, as well as glycosides, gluco-oligosaccharides, sucrose and lactose can act as a donor. 1,4-Benzoquinone or ferricenium ion (ferrocene oxidized by removal of one electron) can serve as acceptor. Unlike EC 1.1.3.10, pyranose oxidase, this fungal enzyme does not interact with O2 and exhibits extremely broad substrate tolerance with variable regioselectivity (C-3, C-2 or C-3 + C-2 or C-3 + C-4) for (di)oxidation of different sugars. D-Glucose is exclusively or preferentially oxidized at C-3 (depending on the enzyme source), but can also be oxidized at C-2 + C-3. The enzyme also acts on 1→4-α- and 1→4-β-gluco-oligosaccharides, non-reducing gluco-oligosaccharides and L-arabinose, which are not substrates of EC 1.1.3.10. Sugars are oxidized in their pyranose but not in their furanose form.
References:
1.  Volc, J., Kubátová, E., Wood, D. and Daniel, G. Pyranose 2-dehydrogenase, a novel sugar oxidoreductase from the basidiomycete fungus Agaricus bisporus. Arch. Microbiol. 167 (1997) 119–125. [PMID: 9042751]
2.  Volc, J., Sedmera, P., Halada, P., Přikyrlová, V. and Daniel, G. C-2 and C-3 oxidation of D-Glc, and C-2 oxidation of D-Gal by pyranose dehydrogenase from Agaricus bisporus. Carbohydr. Res. 310 (1998) 151–156.
3.  Volc, J., Sedmera, P., Halada, P., Přikyrlová, V. and Haltrich, D. Double oxidation of D-xylose to D-glycero-pentos-2,3-diulose (2,3-diketo-D-xylose) by pyranose dehydrogenase from the mushroom Agaricus bisporus. Carbohydr. Res. 329 (2000) 219–225. [PMID: 11086703]
4.  Volc, J., Kubátová, E., Daniel, G., Sedmera, P. and Haltrich, D. Screening of basidiomycete fungi for the quinone-dependent sugar C-2/C-3 oxidoreductase, pyranose dehydrogenase, and properties of the enzyme from Macrolepiota rhacodes. Arch. Microbiol. 176 (2001) 178–186. [PMID: 11511865]
5.  Volc, J., Sedmera, P., Halada, P., Daniel, G., Přikyrlová, V. and Haltrich, D. C-3 oxidation of non-reducing sugars by a fungal pyranose dehydrogenase: spectral characterization. J. Mol. Catal., B Enzym. 17 (2002) 91–100.
[EC 1.1.99.29 created 2004]
 
 
EC 1.1.99.35     
Accepted name: soluble quinoprotein glucose dehydrogenase
Reaction: D-glucose + acceptor = D-glucono-1,5-lactone + reduced acceptor
Other name(s): soluble glucose dehydrogenase; sGDH; glucose dehydrogenase (PQQ-dependent)
Systematic name: D-glucose:acceptor oxidoreductase
Comments: Soluble periplasmic enzyme containing PQQ as prosthetic group, bound to a calcium ion. Electron acceptor is not known. It is assayed with Wurster’s Blue or phenazine methosulfate. It has negligible sequence or structure similarity to other quinoproteins. It catalyses an exceptionally high rate of oxidation of a wide range of aldose sugars, including D-glucose, galactose, arabinose and xylose, and also the disaccharides lactose, cellobiose and maltose. It has been described only in Acinetobacter calcoaceticus.
References:
1.  Geiger, O. and Gorisch, H. Crystalline quinoprotein glucose dehydrogenase from Acinetobacter calcoaceticus. Biochemistry 25 (1986) 6043–6048.
2.  Dokter, P., Frank, J. and Duine, J.A. Purification and characterization of quinoprotein glucose dehydrogenase from Acinetobacter calcoaceticus L.M.D. 79.41. Biochem. J. 239 (1986) 163–167. [PMID: 3800975]
3.  Cleton-Jansen, A.M., Goosen, N., Wenzel, T.J. and van de Putte, P. Cloning of the gene encoding quinoprotein glucose dehydrogenase from Acinetobacter calcoaceticus: evidence for the presence of a second enzyme. J. Bacteriol. 170 (1988) 2121–2125. [PMID: 2834325]
4.  Matsushita, K., Shinagawa, E., Adachi, O. and Ameyama, M. Quinoprotein D-glucose dehydrogenase of the Acinetobacter calcoaceticus respiratory chain: membrane-bound and soluble forms are different molecular species. Biochemistry 28 (1989) 6276–6280. [PMID: 2551369]
5.  Oubrie, A. and Dijkstra, B.W. Structural requirements of pyrroloquinoline quinone dependent enzymatic reactions. Protein Sci. 9 (2000) 1265–1273. [PMID: 10933491]
6.  Matsushita, K., Toyama, H., Ameyama, M., Adachi, O., Dewanti, A. and Duine, J.A. Soluble and membrane-bound quinoprotein D-glucose dehydrogenases of the Acinetobacter calcoaceticus : the binding process of PQQ to the apoenzymes. Biosci. Biotechnol. Biochem. 59 (1995) 1548–1555.
[EC 1.1.99.35 created 2010]
 
 
EC 1.1.99.36     
Accepted name: alcohol dehydrogenase (nicotinoprotein)
Reaction: ethanol + acceptor = acetaldehyde + reduced acceptor
Other name(s): NDMA-dependent alcohol dehydrogenase; nicotinoprotein alcohol dehydrogenase; np-ADH; ethanol:N,N-dimethyl-4-nitrosoaniline oxidoreductase
Systematic name: ethanol:acceptor oxidoreductase
Comments: Contains Zn2+. Nicotinoprotein alcohol dehydrogenases are unique medium-chain dehydrogenases/reductases (MDR) alcohol dehydrogenases that have a tightly bound NAD+/NADH cofactor that does not dissociate during the catalytic process. Instead, the cofactor is regenerated by a second substrate or electron carrier. While the in vivo electron acceptor is not known, N,N-dimethyl-4-nitrosoaniline (NDMA), which is reduced to 4-(hydroxylamino)-N,N-dimethylaniline, can serve this function in vitro. The enzyme from the Gram-positive bacterium Amycolatopsis methanolica can accept many primary alcohols as substrates, including benzylalcohol [1].
References:
1.  Van Ophem, P.W., Van Beeumen, J. and Duine, J.A. Nicotinoprotein [NAD(P)-containing] alcohol/aldehyde oxidoreductases. Purification and characterization of a novel type from Amycolatopsis methanolica. Eur. J. Biochem. 212 (1993) 819–826. [PMID: 8385013]
2.  Piersma, S.R., Visser, A.J., de Vries, S. and Duine, J.A. Optical spectroscopy of nicotinoprotein alcohol dehydrogenase from Amycolatopsis methanolica: a comparison with horse liver alcohol dehydrogenase and UDP-galactose epimerase. Biochemistry 37 (1998) 3068–3077. [PMID: 9485460]
3.  Schenkels, P. and Duine, J.A. Nicotinoprotein (NADH-containing) alcohol dehydrogenase from Rhodococcus erythropolis DSM 1069: an efficient catalyst for coenzyme-independent oxidation of a broad spectrum of alcohols and the interconversion of alcohols and aldehydes. Microbiology 146 (2000) 775–785. [PMID: 10784035]
4.  Piersma, S.R., Norin, A., de Vries, S., Jornvall, H. and Duine, J.A. Inhibition of nicotinoprotein (NAD+-containing) alcohol dehydrogenase by trans-4-(N,N-dimethylamino)-cinnamaldehyde binding to the active site. J. Protein Chem. 22 (2003) 457–461. [PMID: 14690248]
5.  Norin, A., Piersma, S.R., Duine, J.A. and Jornvall, H. Nicotinoprotein (NAD+ -containing) alcohol dehydrogenase: structural relationships and functional interpretations. Cell. Mol. Life Sci. 60 (2003) 999–1006. [PMID: 12827287]
[EC 1.1.99.36 created 2010]
 
 
EC 1.2.1.92     
Accepted name: 3,6-anhydro-α-L-galactose dehydrogenase
Reaction: 3,6-anhydro-α-L-galactopyranose + NAD(P)+ + H2O = 3,6-anhydro-L-galactonate + NAD(P)H + H+
Systematic name: 3,6-anhydro-α-L-galactopyranose:NAD(P)+ 1-oxidoredutase
Comments: The enzyme, characterized from the marine bacterium Vibrio sp. EJY3, is involved in a degradation pathway for 3,6-anhydro-α-L-galactose, a major component of the polysaccharides produced by red macroalgae, such as agarose and porphyran.
References:
1.  Yun, E.J., Lee, S., Kim, H.T., Pelton, J.G., Kim, S., Ko H,-J., Choi I,-G. and Kim, K.H. The novel catabolic pathway of 3,6-anhydro-L-galactose, the main component of red macroalgae, in a marine bacterium. Environ. Microbiol. 17 (2014) 1677–1688. [PMID: 25156229]
[EC 1.2.1.92 created 2014]
 
 
EC 2.3.1.79     
Accepted name: maltose O-acetyltransferase
Reaction: acetyl-CoA + maltose = CoA + 6-O-acetyl-α-D-glucopyranosyl-(1→4)-D-glucose
Other name(s): maltose transacetylase; maltose O-acetyltransferase; MAT
Systematic name: acetyl-CoA:maltose O-acetyltransferase
Comments: Not identical with EC 2.3.1.18, galactoside O-acetyltransferase. The acetyl group is added exclusively to the C6 position of glucose and to the C6 position of the non-reducing glucose residue of maltose [3]. Other substrates of this enzyme are glucose, which is a better substrate than maltose [2], and mannose and frucose, which are poorer substrates than maltose [2]. Isopropyl-β-thio-galactose, which is a good substrate for EC 2.3.1.118 is a poor substrate for this enzyme [3].
References:
1.  Freundlieb, S. and Boos, W. Maltose transacetylase of Escherichia coli: a preliminary report. Ann. Microbiol. (Paris) 133A (1982) 181–189. [PMID: 7041741]
2.  Brand, B. and Boos, W. Maltose transacetylase of Escherichia coli. Mapping and cloning of its structural, gene, mac, and characterization of the enzyme as a dimer of identical polypeptides with a molecular weight of 20,000. J. Biol. Chem. 266 (1991) 14113–14118. [PMID: 1856235]
3.  Lo Leggio, L., Dal Degan, F., Poulsen, P., Andersen, S.M. and Larsen, S. The structure and specificity of Escherichia coli maltose acetyltransferase give new insight into the LacA family of acyltransferases. Biochemistry 42 (2003) 5225–5235. [PMID: 12731863]
[EC 2.3.1.79 created 1984]
 
 
EC 2.3.1.197     
Accepted name: dTDP-3-amino-3,6-dideoxy-α-D-galactopyranose 3-N-acetyltransferase
Reaction: acetyl-CoA + dTDP-3-amino-3,6-dideoxy-α-D-galactopyranose = CoA + dTDP-3-acetamido-3,6-dideoxy-α-D-galactopyranose
Other name(s): FdtC; dTDP-D-Fucp3N acetylase
Systematic name: acetyl-CoA:dTDP-3-amino-3,6-dideoxy-α-D-galactopyranose 3-N-acetyltransferase
Comments: The product, dTDP-3-acetamido-3,6-dideoxy-α-D-galactose, is a component of the glycan chain of the crystalline bacterial cell surface layer protein (S-layer glycoprotein) of Aneurinibacillus thermoaerophilus.
References:
1.  Pfoestl, A., Hofinger, A., Kosma, P. and Messner, P. Biosynthesis of dTDP-3-acetamido-3,6-dideoxy-α-D-galactose in Aneurinibacillus thermoaerophilus L420-91T. J. Biol. Chem. 278 (2003) 26410–26417. [PMID: 12740380]
[EC 2.3.1.197 created 2012]
 
 
EC 2.3.1.210     
Accepted name: dTDP-4-amino-4,6-dideoxy-D-galactose acyltransferase
Reaction: acetyl-CoA + dTDP-4-amino-4,6-dideoxy-α-D-galactose = CoA + dTDP-4-acetamido-4,6-dideoxy-α-D-galactose
Glossary: dTDP-4-amino-4,6-dideoxy-α-D-galactose = dTDP-α-D-fucosamine
Other name(s): TDP-fucosamine acetyltransferase; WecD; RffC
Systematic name: acetyl-CoA:dTDP-4-amino-4,6-dideoxy-α-D-galactose N-acetyltransferase
Comments: The product, TDP-4-acetamido-4,6-dideoxy-D-galactose, is utilized in the biosynthesis of enterobacterial common antigen (ECA).
References:
1.  Hung, M.N., Rangarajan, E., Munger, C., Nadeau, G., Sulea, T. and Matte, A. Crystal structure of TDP-fucosamine acetyltransferase (WecD) from Escherichia coli, an enzyme required for enterobacterial common antigen synthesis. J. Bacteriol. 188 (2006) 5606–5617. [PMID: 16855251]
[EC 2.3.1.210 created 2012]
 
 
EC 2.4.1.22     
Accepted name: lactose synthase
Reaction: UDP-α-D-galactose + D-glucose = UDP + lactose
Other name(s): UDP-galactose—glucose galactosyltransferase; N-acetyllactosamine synthase; uridine diphosphogalactose-glucose galactosyltransferase; lactose synthetase; UDP-galactose:D-glucose 4-β-D-galactotransferase; UDP-galactose:D-glucose 4-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:D-glucose 4-β-D-galactosyltransferase
Comments: The enzyme is a complex of two proteins, A and B. In the absence of the B protein (α-lactalbumin), the enzyme catalyses the transfer of galactose from UDP-α-D-galactose to N-acetylglucosamine (EC 2.4.1.90 N-acetyllactosamine synthase).
References:
1.  Fitzgerald, D.K., Brodbeck, U., Kiyosawa, I., Mawal, R., Colvin, B. and Ebner, K.E. α-Lactalbumin and the lactose synthetase reaction. J. Biol. Chem. 245 (1970) 2103–2108. [PMID: 5440844]
2.  Hill, R.L. and Brew, K. Lactose synthetase. Adv. Enzymol. Relat. Areas Mol. Biol. 43 (1975) 411–490. [PMID: 812340]
3.  Watkins, W.M. and Hassid, W.Z. The synthesis of lactose by particulate enzyme preparations from guinea pig and bovine mammary glands. J. Biol. Chem. 237 (1962) 1432–1440. [PMID: 14005251]
[EC 2.4.1.22 created 1965]
 
 
EC 2.4.1.23     
Accepted name: sphingosine β-galactosyltransferase
Reaction: UDP-α-D-galactose + sphingosine = UDP + psychosine
Other name(s): psychosine—UDP galactosyltransferase; galactosyl-sphingosine transferase; psychosine-uridine diphosphate galactosyltransferase; UDP-galactose:sphingosine O-galactosyl transferase; uridine diphosphogalactose-sphingosine β-galactosyltransferase; UDP-galactose:sphingosine 1-β-galactotransferase; UDP-galactose:sphingosine 1-β-galactosyltransferase
Systematic name: UDP-α-D-galactose:sphingosine 1-β-galactosyltransferase
References:
1.  Cleland, W.W. and Kennedy, E.P. The enzymatic synthesis of psychosine. J. Biol. Chem. 235 (1960) 45–51. [PMID: 13810623]
[EC 2.4.1.23 created 1965]
 
 
EC 2.4.1.37     
Accepted name: fucosylgalactoside 3-α-galactosyltransferase
Reaction: UDP-α-D-galactose + α-L-fucosyl-(1→2)-D-galactosyl-R = UDP + α-D-galactosyl-(1→3)-[α-L-fucosyl(1→2)]-D-galactosyl-R (where R can be OH, an oligosaccharide or a glycoconjugate)
Other name(s): UDP-galactose:O-α-L-fucosyl(1→2)D-galactose α-D-galactosyltransferase; UDPgalactose:glycoprotein-α-L-fucosyl-(1,2)-D-galactose 3-α-D-galactosyltransferase; [blood group substance] α-galactosyltransferase; blood-group substance B-dependent galactosyltransferase; glycoprotein-fucosylgalactoside α-galactosyltransferase; histo-blood group B transferase; histo-blood substance B-dependent galactosyltransferase; UDP-galactose:α-L-fucosyl-1,2-D-galactoside 3-α-D-galactosyltransferase; UDP-galactose:α-L-fucosyl-(1→2)-D-galactoside 3-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:α-L-fucosyl-(1→2)-D-galactoside 3-α-D-galactosyltransferase
Comments: Acts on blood group substance, and can use a number of 2-fucosyl-galactosides as acceptors.
References:
1.  Race, C., Ziderman, D. and Watkins, W.M. An α-D-galactosyltransferase associated with the blood-group B character. Biochem. J. 107 (1968) 733–735. [PMID: 16742598]
[EC 2.4.1.37 created 1972, modified 1999, modified 2002]
 
 
EC 2.4.1.38     
Accepted name: β-N-acetylglucosaminylglycopeptide β-1,4-galactosyltransferase
Reaction: UDP-α-D-galactose + N-acetyl-β-D-glucosaminylglycopeptide = UDP + β-D-galactosyl-(1→4)-N-acetyl-β-D-glucosaminylglycopeptide
Other name(s): UDP-galactose—glycoprotein galactosyltransferase; glycoprotein 4-β-galactosyl-transferase; β-N-acetyl-β1-4-galactosyltransferase; thyroid glycoprotein β-galactosyltransferase; glycoprotein β-galactosyltransferase; thyroid galactosyltransferase; uridine diphosphogalactose-glycoprotein galactosyltransferase; β-N-acetylglucosaminyl-glycopeptide β-1,4-galactosyltransferase; GalT; UDP-galactose:N-acetyl-β-D-glucosaminylglycopeptide β-1,4-galactosyltransferase; UDP-galactose:N-acetyl-β-D-glucosaminylglycopeptide 4-β-galactosyltransferase
Systematic name: UDP-α-D-galactose:N-acetyl-β-D-glucosaminylglycopeptide 4-β-galactosyltransferase
Comments: Terminal N-acetyl-β-D-glucosaminyl residues in polysaccharides, glycoproteins and glycopeptides can act as acceptor. High activity is shown towards such residues in branched-chain polysaccharides when these are linked by β-1,6-links to galactose residues; lower activity towards residues linked to galactose by β-1,3-links. A component of EC 2.4.1.22 (lactose synthase).
References:
1.  Beyer, T.A., Sadler, J.E., Rearick, J.I., Paulson, J.C. and Hill, R.L. Glucosyltransferases and their uses in assessing oligosaccharide structure and structure-function relationship. Adv. Enzymol. 52 (1981) 23–175. [PMID: 6784450]
2.  Blanken, W.M., Hooghwinkel, G.J.M. and van den Eijnden, D.H. Biosynthesis of blood-group I and i substances. Specificity of bovine colostrum β-N-acetyl-D-glucosaminide β1→4 galactosyltransferase. Eur. J. Biochem. 127 (1982) 547–552. [PMID: 6816588]
3.  Blanken, W.M. and van den Eijnden, D.H. Biosynthesis of terminal Gal α 1→3Gal β 1→4GlcNAc-R oligosaccharide sequences on glycoconjugates. Purification and acceptor specificity of a UDP-Gal:N-acetyllactosaminide α 1→3-galactosyltransferase from calf thymus. J. Biol. Chem. 260 (1985) 12927–12934. [PMID: 3932335]
4.  Spiro, M.H. and Spiro, R.G. Glycoprotein biosynthesis: studies on thyroglobulin. Thyroid galactosyltransferase. J. Biol. Chem. 243 (1968) 6529–6537. [PMID: 5726898]
[EC 2.4.1.38 created 1972, modified 1976, modified 1980, modified 1986]
 
 
EC 2.4.1.40     
Accepted name: glycoprotein-fucosylgalactoside α-N-acetylgalactosaminyltransferase
Reaction: UDP-N-acetyl-α-D-galactosamine + glycoprotein-α-L-fucosyl-(1→2)-D-galactose = UDP + glycoprotein-N-acetyl-α-D-galactosaminyl-(1→3)-[α-L-fucosyl-(1→2)]-D-galactose
Other name(s): A-transferase; histo-blood group A glycosyltransferase (Fucα1→2Galα1→3-N-acetylgalactosaminyltransferase); UDP-GalNAc:Fucα1→2Galα1→3-N-acetylgalactosaminyltransferase; α-3-N-acetylgalactosaminyltransferase; blood-group substance α-acetyltransferase; blood-group substance A-dependent acetylgalactosaminyltransferase; fucosylgalactose acetylgalactosaminyltransferase; histo-blood group A acetylgalactosaminyltransferase; histo-blood group A transferase; UDP-N-acetyl-D-galactosamine:α-L-fucosyl-1,2-D-galactose 3-N-acetyl-D-galactosaminyltransferase; UDP-N-acetyl-D-galactosamine:glycoprotein-α-L-fucosyl-(1,2)-D-galactose 3-N-acetyl-D-galactosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-galactosamine:glycoprotein-α-L-fucosyl-(1→2)-D-galactose 3-N-acetyl-D-galactosaminyltransferase
Comments: Acts on blood group substance, and can use a number of 2-fucosyl-galactosides as acceptors.
References:
1.  Kobata, A., Grollman, E.F. and Ginsburg, V. An enzymic basis for blood type A in humans. Arch. Biochem. Biophys. 124 (1968) 609–612. [PMID: 5661629]
2.  Takeya, A., Hosomi, O. and Ishiura, M. Complete purification and characterization of α-3-N-acetylgalactosaminyltransferase encoded by the human blood group A gene. J. Biochem. (Tokyo) 107 (1990) 360–368. [PMID: 2341371]
3.  Yates, A.D., Feeney, J., Donald, A.S.R. and Watkins, W.M. Characterization of a blood-group A-active tetrasaccharide synthesized by a blood-group-B gene-specified glycosyltransferase. Carbohydr. Res. 130 (1984) 251–260. [PMID: 6434182]
[EC 2.4.1.40 created 1972, modified 1999]
 
 
EC 2.4.1.44     
Accepted name: lipopolysaccharide 3-α-galactosyltransferase
Reaction: UDP-α-D-galactose + lipopolysaccharide = UDP + 3-α-D-galactosyl-[lipopolysaccharide glucose]
Other name(s): UDP-galactose:lipopolysaccharide α,3-galactosyltransferase; UDP-galactose:polysaccharide galactosyltransferase; uridine diphosphate galactose:lipopolysaccharide α-3-galactosyltransferase; uridine diphosphogalactose-lipopolysaccharide α,3-galactosyltransferase; UDP-galactose:lipopolysaccharide 3-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:lipopolysaccharide 3-α-D-galactosyltransferase
Comments: Transfers α-D-galactosyl residues to D-glucose in the partially completed core of lipopolysaccharide [cf. EC 2.4.1.56 (lipopolysaccharide N-acetylglucosaminyltransferase), EC 2.4.1.58 (lipopolysaccharide glucosyltransferase I) and EC 2.4.1.73 (lipopolysaccharide glucosyltransferase II)].
References:
1.  Endo, A. and Rothfield, L. Studies of a phospholipid-requiring bacterial enzyme. I. Purification and properties of uridine diphosphate galactose: lipopolysaccharide α-3-galactosyl transferase. Biochemistry 8 (1969) 3500–3507. [PMID: 4898284]
2.  Wollin, R., Creeger, E.S., Rothfield, L.I., Stocker, B.A.D. and Lindberg, A.A. Salmonella typhimurium mutants defective in UDP-D-galactose:lipopolysaccharide α-1,6-D-galactosyltransferase. Structural, immunochemical, and enzymologic studies of rfaB mutants. J. Biol. Chem. 258 (1983) 3769–3774. [PMID: 6403519]
[EC 2.4.1.44 created 1972, modified 2002]
 
 
EC 2.4.1.45      
Deleted entry: 2-hydroxyacylsphingosine 1-β-galactosyltransferase, now included with EC 2.4.1.47, N-acylsphingosine galactosyltransferase
[EC 2.4.1.45 created 1972, deleted 2016]
 
 
EC 2.4.1.46     
Accepted name: monogalactosyldiacylglycerol synthase
Reaction: UDP-α-D-galactose + a 1,2-diacyl-sn-glycerol = UDP + a 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol
Other name(s): uridine diphosphogalactose-1,2-diacylglycerol galactosyltransferase; UDP-galactose:diacylglycerol galactosyltransferase; MGDG synthase; UDP galactose-1,2-diacylglycerol galactosyltransferase; UDP-galactose-diacylglyceride galactosyltransferase; UDP-galactose:1,2-diacylglycerol 3-β-D-galactosyltransferase; 1β-MGDG; 1,2-diacylglycerol 3-β-galactosyltransferase; UDP-galactose:1,2-diacyl-sn-glycerol 3-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:1,2-diacyl-sn-glycerol 3-β-D-galactosyltransferase
Comments: This enzyme adds only one galactosyl group to the diacylglycerol; EC 2.4.1.241, digalactosyldiacylglycerol synthase, adds a galactosyl group to the product of the above reaction. There are three isoforms in Arabidopsis that can be divided into two types, A-type (MGD1) and B-type (MGD2 and MGD3). MGD1 is the isoform responsible for the bulk of monogalactosyldiacylglycerol (MGDG) synthesis in Arabidopsis [4].
References:
1.  Veerkamp, J.H. Biochemical changes in Bifidobacterium bifidum var. pennsylvanicus after cell-wall inhibition. VI. Biosynthesis of the galactosyldiglycerides. Biochim. Biophys. Acta 348 (1974) 23–34. [PMID: 4838219]
2.  Wenger, D.A., Petipas, J.W. and Pieringer, R.A. The metabolism of glyceride glycolipids. II. Biosynthesis of monogalactosyl diglyceride from uridine diphosphate galactose and diglyceride in brain. Biochemistry 7 (1968) 3700–3707. [PMID: 5681471]
3.  Miège, C., Maréchal, E., Shimojima, M., Awai, K., Block, M.A., Ohta, H., Takamiya, K., Douce, R. and Joyard, J. Biochemical and topological properties of type A MGDG synthase, a spinach chloroplast envelope enzyme catalyzing the synthesis of both prokaryotic and eukaryotic MGDG. Eur. J. Biochem. 265 (1999) 990–1001. [PMID: 10518794]
4.  Benning, C. and Ohta, H. Three enzyme systems for galactoglycerolipid biosynthesis are coordinately regulated in plants. J. Biol. Chem. 280 (2005) 2397–2400. [PMID: 15590685]
[EC 2.4.1.46 created 1972, modified 2003, modified 2005]
 
 
EC 2.4.1.47     
Accepted name: N-acylsphingosine galactosyltransferase
Reaction: UDP-α-D-galactose + a ceramide = UDP + a β-D-galactosylceramide
Glossary: a ceramide = an N-acylsphingosine
Other name(s): UGT8 (gene name); CGT (gene name); UDP galactose-N-acylsphingosine galactosyltransferase; uridine diphosphogalactose-acylsphingosine galactosyltransferase; UDP-galactose:N-acylsphingosine D-galactosyltransferase; UDP-α-D-galactose:N-acylsphingosine D-galactosyltransferase; 2-hydroxyacylsphingosine 1-β-galactosyltransferase
Systematic name: UDP-α-D-galactose:N-acylsphingosine β-D-galactosyltransferase (configuration-inverting)
Comments: This membrane-bound, endoplasmic reticulum-located enzyme catalyses the last step in the synthesis of galactocerebrosides, which are abundant sphingolipids of the myelin membrane of the central nervous system and peripheral nervous system. It has a strong preference for ceramides that contain hydroxylated fatty acids.
References:
1.  Fujino, Y. and Nakano, M. Enzymic synthesis of cerebroside from ceramide and uridine diphosphate galactose. Biochem. J. 113 (1969) 573–575. [PMID: 5807218]
2.  Morell, P. and Radin, N.S. Synthesis of cerebroside by brain from uridine diphosphate galactose and ceramide containing hydroxy fatty acid. Biochemistry 8 (1969) 506–512. [PMID: 5793706]
3.  Morell, P., Costantino-Ceccarini, E. and Radin, N.S. The biosynthesis by brain microsomes of cerebrosides containing nonhydroxy fatty acids. Arch. Biochem. Biophys. 141 (1970) 738–748. [PMID: 5497154]
4.  Basu, S., Schultz, A., Basu, M. and Roseman, S. Enzymatic synthesis of galactocerebroside by a galactosyltransferase from embryonic chicken brain. J. Biol. Chem. 243 (1971) 4272–4279. [PMID: 5090043]
5.  Akanuma, H. and Kishimoto, Y. Synthesis of ceramides and cerebrosides containing both α-hydroxy and nonhydroxy fatty acids from lignoceroyl-CoA by rat brain microsomes. J. Biol. Chem. 254 (1979) 1050–1060. [PMID: 762114]
6.  Koul, O. and Jungalwala, F.B. UDP-galactose:ceramide galactosyltransferase of rat central-nervous-system myelin. Biochem. J. 194 (1981) 633–637. [PMID: 7306007]
7.  Schulte, S. and Stoffel, W. Ceramide UDP-galactosyltransferase from myelinating rat brain: purification, cloning, and expression. Proc. Natl. Acad. Sci. USA 90 (1993) 10265–10269. [PMID: 7694285]
8.  Sprong, H., Kruithof, B., Leijendekker, R., Slot, J.W., van Meer, G. and van der Sluijs, P. UDP-galactose:ceramide galactosyltransferase is a class I integral membrane protein of the endoplasmic reticulum. J. Biol. Chem. 273 (1998) 25880–25888. [PMID: 9748263]
9.  Fewou, S.N., Bussow, H., Schaeren-Wiemers, N., Vanier, M.T., Macklin, W.B., Gieselmann, V. and Eckhardt, M. Reversal of non-hydroxy:α-hydroxy galactosylceramide ratio and unstable myelin in transgenic mice overexpressing UDP-galactose:ceramide galactosyltransferase. J. Neurochem. 94 (2005) 469–481. [PMID: 15998297]
[EC 2.4.1.47 created 1972]
 
 
EC 2.4.1.48     
Accepted name: heteroglycan α-mannosyltransferase
Reaction: GDP-mannose + heteroglycan = GDP + 2(or 3)-α-D-mannosyl-heteroglycan
Other name(s): GDP mannose α-mannosyltransferase; guanosine diphosphomannose-heteroglycan α-mannosyltransferase
Systematic name: GDP-mannose:heteroglycan 2-(or 3-)-α-D-mannosyltransferase
Comments: The acceptor is a heteroglycan primer containing mannose, galactose and xylose. 1,2- and 1,3-mannosyl bonds are formed.
References:
1.  Ankel, H., Ankel, E., Schutzbach, J. and Garancis, J.C. Mannosyl transfer in Cryptococcus laurentii. J. Biol. Chem. 245 (1970) 3945–3955. [PMID: 5492958]
[EC 2.4.1.48 created 1972]
 
 
EC 2.4.1.50     
Accepted name: procollagen galactosyltransferase
Reaction: UDP-α-D-galactose + [procollagen]-(5R)-5-hydroxy-L-lysine = UDP + [procollagen]-(5R)-5-O-(β-D-galactosyl)-5-hydroxy-L-lysine
Other name(s): hydroxylysine galactosyltransferase; collagen galactosyltransferase; collagen hydroxylysyl galactosyltransferase; UDP galactose-collagen galactosyltransferase; uridine diphosphogalactose-collagen galactosyltransferase; UDPgalactose:5-hydroxylysine-collagen galactosyltransferase; UDP-galactose:procollagen-5-hydroxy-L-lysine D-galactosyltransferase; UDP-α-D-galactose:procollagen-5-hydroxy-L-lysine D-galactosyltransferase
Systematic name: UDP-α-D-galactose:[procollagen]-(5R)-5-hydroxy-L-lysine 5-β-D-galactosyltransferase (configuration-inverting)
Comments: Involved in the synthesis of carbohydrate units in the complement system (cf. EC 2.4.1.66 procollagen glucosyltransferase).
References:
1.  Bosmann, H.B. and Eylar, E.H. Glycoprotein biosynthesis: the biosynthesis of the hydroxylysine-galactose linkage in collagen. Biochem. Biophys. Res. Commun. 33 (1968) 340–346. [PMID: 5722225]
2.  Kivirikko, K.I. and Myllyla, R. In: Hall, D.A. and Jackson, D.S. (Ed.), International Review of Connective Tissue Research, vol. 8, Academic Press, New York, 1979, p. 23.
3.  Schegg, B., Hulsmeier, A.J., Rutschmann, C., Maag, C. and Hennet, T. Core glycosylation of collagen is initiated by two β(1-O)galactosyltransferases. Mol. Cell Biol. 29 (2009) 943–952. [PMID: 19075007]
[EC 2.4.1.50 created 1972, modified 1983]
 
 
EC 2.4.1.56     
Accepted name: lipopolysaccharide N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + lipopolysaccharide = UDP + N-acetyl-α-D-glucosaminyllipopolysaccharide
Other name(s): UDP-N-acetylglucosamine-lipopolysaccharide N-acetylglucosaminyltransferase; uridine diphosphoacetylglucosamine-lipopolysaccharide acetylglucosaminyltransferase; UDP-N-acetyl-D-glucosamine:lipopolysaccharide N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:lipopolysaccharide N-acetyl-D-glucosaminyltransferase
Comments: Transfers N-acetylglucosaminyl residues to a D-galactose residue in the partially completed lipopolysaccharide core [cf. EC 2.4.1.44 (lipopolysaccharide 3-α-galactosyltransferase), EC 2.4.1.58 (lipopolysaccharide glucosyltransferase I) and EC 2.4.1.73 (lipopolysaccharide glucosyltransferase II)].
References:
1.  Osborn, M.J. and D'Ari, L. Enzymatic incorporation of N-acetylglucosamine into cell wall lipopolysaccharide in a mutant strain of Salmonella typhimurium. Biochem. Biophys. Res. Commun. 16 (1964) 568–575. [PMID: 5332855]
[EC 2.4.1.56 created 1972]
 
 
EC 2.4.1.58     
Accepted name: lipopolysaccharide glucosyltransferase I
Reaction: UDP-glucose + lipopolysaccharide = UDP + D-glucosyl-lipopolysaccharide
Other name(s): UDP-glucose:lipopolysaccharide glucosyltransferase I; lipopolysaccharide glucosyltransferase; uridine diphosphate glucose:lipopolysaccharide glucosyltransferase I; uridine diphosphoglucose-lipopolysaccharide glucosyltransferase
Systematic name: UDP-glucose:lipopolysaccharide glucosyltransferase
Comments: Transfers glucosyl residues to the backbone portion of lipopolysaccharide [cf. EC 2.4.1.44 (lipopolysaccharide 3-α-galactosyltransferase, EC 2.4.1.56 (lipopolysaccharide N-acetylglucosaminyltransferase) and EC 2.4.1.73 (lipopolysaccharide glucosyltransferase II)].
References:
1.  Müller, E., Hinckley, A. and Rothfield, L. Studies of phospholipid-requiring bacterial enzymes. 3. Purification and properties of uridine diphosphate glucose:lipopolysaccharide glucosyltransferase I. J. Biol. Chem. 247 (1972) 2614–2622. [PMID: 4553445]
2.  Rothfield, L., Osborn, M.J. and Horecker, B.L. Biosynthesis of bacterial lipopolysaccharide. II. Incorporation of glucose and galactose catalyzed by particulate and soluble enzymes in salmonella. J. Biol. Chem. 239 (1964) 2788–2795. [PMID: 14217875]
[EC 2.4.1.58 created 1972]
 
 
EC 2.4.1.60     
Accepted name: CDP-abequose:α-D-Man-(1→4)-α-L-Rha-(1→3)-α-D-Gal-PP-Und α-1,3-abequosyltransferase
Reaction: CDP-α-D-abequose + α-D-Man-(1→4)-α-L-Rha-(1→3)-α-D-Gal-PP-Und = CDP + α-D-Abe-(1→3)-α-D-Man-(1→4)-α-L-Rha-(1→3)-α-D-Gal-PP-Und
Glossary: D-abequose = 3,6-deoxy-D-xylo-hexose = 3,6-deoxy-D-galactose = 3-deoxy-D-fucose
α-D-Man-(1→4)-α-L-Rha-(1→3)-α-D-Gal-PP-Und = α-D-mannopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→3)-α-D-galactopyranosyl-diphospho-ditrans,octacis-undecaprenol
α-D-Abe-(1→3)-α-D-Man-(1→4)-α-L-Rha-(1→3)-α-D-Gal-PP-Und = α-D-abequopyranosyl-(1→3)-α-D-mannopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→3)-α-D-galactopyranosyl-diphospho-ditrans,octacis-undecaprenol
Other name(s): wbaV (gene name); rfbV (gene name); trihexose diphospholipid abequosyltransferase; abequosyltransferase (ambiguous); CDP-α-D-abequose:Man(α1→4)Rha(α1→3)Gal(β-1)-diphospholipid D-abequosyltransferase
Systematic name: CDP-α-D-abequose:α-D-mannopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→3)-α-D-galactopyranosyl-diphospho-ditrans,octacis-undecaprenol 3III-α-abequosyltransferase (configuration retaining)
Comments: The enzyme from Salmonella participates in the biosynthesis of the repeat unit of O antigens produced by strains that belong to the A, B and D1-D3 groups. The enzyme is able to transfer abequose, paratose, or tyvelose, depending on the availability of the specific dideoxyhexose in a particular strain.
References:
1.  Osborn, M.J. and Weiner, I.M. Biosynthesis of a bacterial lipopolysaccharide. VI. Mechanism of incorporation of abequose into the O-antigen of Salmonella typhimurium. J. Biol. Chem. 243 (1968) 2631–2639. [PMID: 4297268]
2.  Liu, D., Lindqvist, L. and Reeves, P.R. Transferases of O-antigen biosynthesis in Salmonella enterica: dideoxyhexosyltransferases of groups B and C2 and acetyltransferase of group C2. J. Bacteriol. 177 (1995) 4084–4088. [PMID: 7541787]
[EC 2.4.1.60 created 1972, modified 2012, modified 2021]
 
 
EC 2.4.1.62     
Accepted name: ganglioside galactosyltransferase
Reaction: UDP-α-D-galactose + an N-acetyl-β-D-galactosaminyl-(1→4)-[α-N-acetylneuraminyl-(2→3)]-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide = UDP + a β-D-galactosyl-(1→3)-N-acetyl-β-D-galactosaminyl-(1→4)-[α-N-acetylneuraminyl-(2→3)]-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide
Glossary: N-acetyl-β-D-galactosaminyl-(1→4)-[α-N-acetylneuraminyl-(2→3)]-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide = ganglioside GM2
a β-D-galactosyl-(1→3)-N-acetyl-β-D-galactosaminyl-(1→4)-[α-N-acetylneuraminyl-(2→3)]-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide = gangloside GM1a
Other name(s): UDP-galactose—ceramide galactosyltransferase; uridine diphosphogalactose-ceramide galactosyltransferase; UDP galactose-LAC Tet-ceramide α-galactosyltransferase; UDP-galactose-GM2 galactosyltransferase; uridine diphosphogalactose-GM2 galactosyltransferase; uridine diphosphate D-galactose:glycolipid galactosyltransferase; UDP-galactose:N-acetylgalactosaminyl-(N-acetylneuraminyl) galactosyl-glucosyl-ceramide galactosyltransferase; UDP-galactose-GM2 ganglioside galactosyltransferase; GM1-synthase; UDP-galactose:N-acetyl-D-galactosaminyl-(N-acetylneuraminyl)-D-galactosyl-D-glucosyl-N-acylsphingosine β-1,3-D-galactosyltransferase; UDP-galactose:N-acetyl-D-galactosaminyl-(N-acetylneuraminyl)-D-galactosyl-(1→4)-β-D-glucosyl-N-acylsphingosine 3-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:N-acetyl-β-D-galactosaminyl-(1→4)-[α-N-acetylneuraminyl-(2→3)]-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide 3-β-D-galactosyltransferase
Comments: The substrate is also known as gangloside GM2, the product as gangloside GM1a
References:
1.  Basu, S., Kaufman, B. and Roseman, S. Conversion of Tay-Sachs ganglioside to monosialoganglioside by brain uridine diphosphate D-galactose: glycolipid galactosyltransferase. J. Biol. Chem. 240 (1965) 4115–4117. [PMID: 5842076]
2.  Yip, G.B. and Dain, J.A. The enzymic synthesis of ganglioside. II. UDP-galactose: N-acetylgalactosaminyl-(N-acetylneuraminyl)galactosyl-glucosyl-ceramide galactosyltransferase in rat brain. Biochim. Biophys. Acta 206 (1970) 252–260. [PMID: 4987145]
3.  Yip, M.C.M. and Dain, J.A. Frog brain uridine diphosphate galactose-N-acetylgalactosaminyl-N-acetylneuraminylgalactosylglucosylceramide galactosyltransferase. Biochem. J. 118 (1970) 247–252. [PMID: 5484669]
[EC 2.4.1.62 created 1972, modified 2013]
 
 
EC 2.4.1.65     
Accepted name: 3-galactosyl-N-acetylglucosaminide 4-α-L-fucosyltransferase
Reaction: GDP-β-L-fucose + β-D-galactosyl-(1→3)-N-acetyl-β-D-glucosaminyl-R = GDP + β-D-galactosyl-(1→3)-[α-L-fucosyl-(1→4)]-N-acetyl-β-D-glucosaminyl-R
Other name(s): (Lea)-dependent (α-3/4)-fucosyltransferase; α(1,3/1,4) fucosyltransferase III; α-(1→4)-L-fucosyltransferase; α-4-L-fucosyltransferase; β-acetylglucosaminylsaccharide fucosyltransferase; FucT-II; Lewis α-(1→3/4)-fucosyltransferase; Lewis blood group α-(1→3/4)-fucosyltransferase; Lewis(Le) blood group gene-dependent α-(1→3/4)-L-fucosyltransferase; blood group Lewis α-4-fucosyltransferase; blood-group substance Lea-dependent fucosyltransferase; guanosine diphosphofucose-β-acetylglucosaminylsaccharide 4-α-L-fucosyltransferase; guanosine diphosphofucose-glycoprotein 4-α-L-fucosyltransferase; guanosine diphosphofucose-glycoprotein 4-α-fucosyltransferase; 3-α-galactosyl-N-acetylglucosaminide 4-α-L-fucosyltransferase; GDP-β-L-fucose:3-β-D-galactosyl-N-acetyl-D-glucosaminyl-R 4I-α-L-fucosyltransferase; GDP-L-fucose:3-β-D-galactosyl-N-acetyl-D-glucosaminyl-R 4I-α-L-fucosyltransferase
Systematic name: GDP-β-L-fucose:β-D-galactosyl-(1→3)-N-acetyl-β-D-glucosaminyl-R 4I-α-L-fucosyltransferase (configuration-inverting)
Comments: This enzyme is the product of the Lewis blood group gene. Normally acts on a glycoconjugate where R (see reaction) is a glycoprotein or glycolipid. Although it is a 4-fucosyltransferase, it has a persistent 3-fucosyltransferase activity towards the glucose residue in free lactose. This enzyme fucosylates on O-4 of an N-acetylglucosamine that carries a galactosyl group on O-3, unlike EC 2.4.1.152, 4-galactosyl-N-acetylglucosaminide 3-α-L-fucosyltransferase, which fucosylates on O-3 of an N-acetylglucosamine that carries a galactosyl group on O-4. Enzymes catalysing the 4-α-fucosylation of the GlcNAc in β-D-Gal-(1→3)-β-GlcNAc sequences (with some activity also as 3-α-fucosyltransferases) are present in plants, where the function in vivo is the modification of N-glycans. In addition, the fucTa gene of Helicobacter strain UA948 encodes a fucosyltransferase with both 3-α- and 4-α-fucosyltransferase activities.
References:
1.  Prieels, J.-P., Monnom, D., Dolmans, M., Beyer, T.A. and Hill, R.L. Co-purification of the Lewis blood group N-acetylglucosaminide α1→4 fucosyltransferase and an N-acetylglucosaminide α1→3 fucosyltransferase from human milk. J. Biol. Chem. 256 (1981) 10456–10463. [PMID: 7287719]
2.  Rasko, D.A., Wang, G., Palcic, M.M. and Taylor, D.E. Cloning and characterization of the α(1,3/4) fucosyltransferase of Helicobacter pylori. J. Biol. Chem. 275 (2000) 4988–4994. [PMID: 10671538]
3.  Wilson, I.B.H. Identification of a cDNA encoding a plant Lewis-type α1,4-fucosyltransferase. Glycoconj. J. 18 (2001) 439–447. [PMID: 12084979]
4.  Ma, B., Wang, G., Palcic, M.M., Hazes, B. and Taylor, D.E. C-terminal amino acids of Helicobacter pylori α1,3/4 fucosyltransferases determine type I and type II transfer. J. Biol. Chem. 278 (2003) 21893–21900. [PMID: 12676935]
[EC 2.4.1.65 created 1972, modified 2001, modified twice 2002]
 
 
EC 2.4.1.73     
Accepted name: lipopolysaccharide glucosyltransferase II
Reaction: UDP-glucose + lipopolysaccharide = UDP + α-D-glucosyl-lipopolysaccharide
Other name(s): uridine diphosphoglucose-galactosylpolysaccharide glucosyltransferase
Systematic name: UDP-glucose:galactosyl-lipopolysaccharide α-D-glucosyltransferase
Comments: Transfers glucosyl residues to the D-galactosyl-D-glucosyl side-chains in the partially completed core of lipopolysaccharides. cf. EC 2.4.1.44 (lipopolysaccharide 3-α-galactosyltransferase), EC 2.4.1.56 (lipopolysaccharide N-acetylglucosaminyltransferase) and EC 2.4.1.58 (lipopolysaccharide glucosyltransferase I).
References:
1.  Edstrom, R.D. and Heath, E.C. The biosynthesis of cell wall lipopolysaccharide in Escherichia coli. VI. Enzymatic transfer of galactose, glucose, N-acetylglucosamine, and colitose into the polymer. J. Biol. Chem. 242 (1967) 3581–3588. [PMID: 5341482]
[EC 2.4.1.73 created 1972]
 
 
EC 2.4.1.74     
Accepted name: glycosaminoglycan galactosyltransferase
Reaction: UDP-α-D-galactose + glycosaminoglycan = UDP + D-galactosylglycosaminoglycan
Other name(s): uridine diphosphogalactose-mucopolysaccharide galactosyltransferase; UDP-galactose:glycosaminoglycan D-galactosyltransferase
Systematic name: UDP-α-D-galactose:glycosaminoglycan D-galactosyltransferase
Comments: Involved in the biosynthesis of galactose-containing glycosaminoglycan of the ameboid protozoan Dictyostelium discoideum.
References:
1.  Sussman, M. and Osborn, M.J. UDP-glucose polysaccharide transferase in the cellular slime mold Dictyostelium discoideum: appearance and dissappearance of activity during cell differentiation. Proc. Natl. Acad. Sci. USA 52 (1964) 81–87. [PMID: 14192661]
[EC 2.4.1.74 created 1972, modified 1980]
 
 
EC 2.4.1.86     
Accepted name: N-acetyl-β-D-glucosaminide β-(1,3)-galactosyltransferase
Reaction: UDP-α-D-galactose + N-acetyl-β-D-glucosaminyl-R = UDP + β-D-galactosyl-(1→3)-N-acetyl-β-D-glucosaminyl-R
Other name(s): B3GALT1 (gene name); uridine diphosphogalactose-acetyl-glucosaminylgalactosylglucosylceramide galactosyltransferase; GalT-4; UDP-galactose:N-acetyl-D-glucosaminyl-1,3-D-galactosyl-1,4-D-glucosylceramide β-D-galactosyltransferase; UDP-galactose:N-acetyl-D-glucosaminyl-(1→3)-D-galactosyl-(1→4)-D-glucosylceramide 3-β-D-galactosyltransferase; UDP-galactose:N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosylceramide 3-β-D-galactosyltransferase; UDP-galactose:N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl(1↔1)ceramide 3-β-D-galactosyltransferase; UDP-galactose:N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide 3-β-D-galactosyltransferase; glucosaminylgalactosylglucosylceramide β-galactosyltransferase; UDP-α-D-galactose:N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide 3-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:N-acetyl-β-D-glucosaminyl-R 3-β-D-galactosyltransferase
Comments: The enzyme transfers galactose from UDP-α-D-galactose to the 3-position of substrates with a non-reducing terminal N-acetyl-β-D-glucosamine (β-GlcNAc) residue. It can act on both glycolipids and glycoproteins, generating a structure known as the type 1 histo-blood group antigen precursor.
References:
1.  Basu, M. and Basu, S. Enzymatic synthesis of a tetraglycosylceramide by a galactosyltransferase from rabbit bone marrow. J. Biol. Chem. 247 (1972) 1489–1495. [PMID: 4335001]
2.  Basu, M., Presper, K.A., Basu, S., Hoffman, L.M. and Brooks, S.E. Differential activities of glycolipid glycosyltransferases in Tay-Sachs disease: studies in cultured cells from cerebrum. Proc. Natl. Acad. Sci. USA 76 (1979) 4270–4274. [PMID: 291963]
3.  Amado, M., Almeida, R., Carneiro, F., Levery, S.B., Holmes, E.H., Nomoto, M., Hollingsworth, M.A., Hassan, H., Schwientek, T., Nielsen, P.A., Bennett, E.P. and Clausen, H. A family of human β3-galactosyltransferases. Characterization of four members of a UDP-galactose:β-N-acetyl-glucosamine/β-nacetyl-galactosamine β-1,3-galactosyltransferase family. J. Biol. Chem. 273 (1998) 12770–12778. [PMID: 9582303]
4.  Amado, M., Almeida, R., Schwientek, T. and Clausen, H. Identification and characterization of large galactosyltransferase gene families: galactosyltransferases for all functions. Biochim. Biophys. Acta 1473 (1999) 35–53. [PMID: 10580128]
5.  Bardoni, A., Valli, M. and Trinchera, M. Differential expression of β1,3galactosyltransferases in human colon cells derived from adenocarcinomas or normal mucosa. FEBS Lett. 451 (1999) 75–80. [PMID: 10356986]
[EC 2.4.1.86 created 1976, modified 2017]
 
 
EC 2.4.1.87     
Accepted name: N-acetyllactosaminide 3-α-galactosyltransferase
Reaction: UDP-α-D-galactose + β-D-galactosyl-(1→4)-β-N-acetyl-D-glucosaminyl-R = UDP + α-D-galactosyl-(1→3)-β-D-galactosyl-(1→4)-β-N-acetylglucosaminyl-R (where R can be OH, an oligosaccharide or a glycoconjugate)
Other name(s): α-galactosyltransferase; UDP-Gal:β-D-Gal(1,4)-D-GlcNAc α(1,3)-galactosyltransferase; UDP-Gal:N-acetyllactosaminide α(1,3)-galactosyltransferase; UDP-Gal:N-acetyllactosaminide α-1,3-D-galactosyltransferase; UDP-Gal:Galβ1→4GlcNAc-R α1→3-galactosyltransferase; UDP-galactose-acetyllactosamine α-D-galactosyltransferase; UDPgalactose:β-D-galactosyl-β-1,4-N-acetyl-D-glucosaminyl-glycopeptide α-1,3-D-galactosyltransferase; glucosaminylglycopeptide α-1,3-galactosyltransferase; uridine diphosphogalactose-acetyllactosamine α1→3-galactosyltransferase; uridine diphosphogalactose-acetyllactosamine galactosyltransferase; uridine diphosphogalactose-galactosylacetylglucosaminylgalactosylglucosylceramide galactosyltransferase; β-D-galactosyl-N-acetylglucosaminylglycopeptide α-1,3-galactosyltransferase; UDP-galactose:N-acetyllactosaminide 3-α-D-galactosyltransferase; UDP-galactose:β-D-galactosyl-1,4-β-N-acetyl-D-glucosaminyl-R 3-α-D-galactosyltransferase; UDP-galactose:β-D-galactosyl-(1→4)-β-N-acetyl-D-glucosaminyl-R 3-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:β-D-galactosyl-(1→4)-β-N-acetyl-D-glucosaminyl-R 3-α-D-galactosyltransferase
Comments: Acts on β-galactosyl-1,4-N-acetylglucosaminyl termini on asialo-α1-acid glycoprotein and N-acetyllactosamine (β-D-galactosyl-1,4-N-acetyl-β-D-glucosamine), but not on 2′-fucosylated-N-acetyllactosamine. The non-reducing terminal N-acetyllactosamine residues of glycoproteins can also act as acceptor. Now includes EC 2.4.1.124 and EC 2.4.1.151.
References:
1.  Basu, M. and Basu, S. Enzymatic synthesis of a blood group B-related pentaglycosylceramide by an α-galactosyltransferase from rabbit bone marrow. J. Biol. Chem. 248 (1973) 1700–1706. [PMID: 4632915]
2.  Blanken, W.M. and van den Eijnden, D.H. Biosynthesis of terminal Gal α 1→3Gal β 1→4GlcNAc-R oligosaccharide sequences on glycoconjugates. Purification and acceptor specificity of a UDP-Gal:N-acetyllactosaminide α 1→3-galactosyltransferase from calf thymus. J. Biol. Chem. 260 (1985) 12927–12934. [PMID: 3932335]
3.  Blake, D.A. and Goldstein, I.J. An α-D-galactosyltransferase activity in Ehrlich ascites tumor cells. Biosynthesis and characterization of a trisaccharide (α-D-galactose-(1→3)-N-acetyllactosamine). J. Biol. Chem. 256 (1981) 5387–5393. [PMID: 6787040]
[EC 2.4.1.87 created 1976, modified 1989, modified 2002 (EC 2.4.1.124 created 1984, incorporated 2002, EC 2.4.1.151 created 1984, incorporated 2002)]
 
 
EC 2.4.1.90     
Accepted name: N-acetyllactosamine synthase
Reaction: UDP-α-D-galactose + N-acetyl-D-glucosamine = UDP + N-acetyllactosamine
Other name(s): UDP-galactoseN-acetylglucosamine β-D-galactosyltransferase; uridine diphosphogalactose-acetylglucosamine galactosyltransferase; β-1,4-galactosyltransferase; acetyllactosamine synthetase; lactosamine synthase; lactosamine synthetase; lactose synthetase A protein; N-acetyllactosamine synthetase; UDP-galactose N-acetylglucosamine β-4-galactosyltransferase; UDP-galactose-acetylglucosamine galactosyltransferase; UDP-galactose-N-acetylglucosamine β-1,4-galactosyltransferase; UDP-galactose-N-acetylglucosamine galactosyltransferase; β1-4-galactosyltransferase; UDP-Gal:N-acetylglucosamine β1-4-galactosyltransferase; β1-4GalT; NAL synthetase; UDP-β-1,4-galactosyltransferase; Gal-T; UDP-galactose:N-acetylglucosaminide β1-4-galactosyltransferase; UDPgalactose:N-acetylglucosaminyl(β1-4)galactosyltransferase; β-N-acetylglucosaminide β1-4-galactosyltransferase; UDP-galactose:N-acetyl-D-glucosamine 4-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:N-acetyl-D-glucosamine 4-β-D-galactosyltransferase
Comments: The reaction is catalysed by a component of EC 2.4.1.22 (lactose synthase), which is identical with EC 2.4.1.38 (β-N-acetylglucosaminyl-glycopeptide β-1,4-galactosyltransferase), and by an enzyme from the Golgi apparatus of animal tissues. Formerly listed also as EC 2.4.1.98.
References:
1.  Deshmukh, D.S., Bear, W.D. and Soifer, D. Isolation and characterization of an enriched Golgi fraction from rat brain. Biochim. Biophys. Acta 542 (1978) 284–295. [PMID: 99178]
2.  Helting, T. and Erbing, B. Galactosyl transfer in mouse mastocytoma: purification and properties of N-acetyllactosamine synthetase. Biochim. Biophys. Acta 293 (1973) 94–104. [PMID: 4631039]
3.  Hill, R.L. and Brew, K. Lactose synthetase. Adv. Enzymol. Relat. Areas Mol. Biol. 43 (1975) 411–490. [PMID: 812340]
4.  Humphreys-Beher, M.G. Isolation and characterization of UDP-galactose:N-acetylglucosamine 4 β-galactosyltransferase activity induced in rat parotid glands treated with isoproterenol. J. Biol. Chem. 259 (1984) 5797–5802. [PMID: 6201486]
5.  Schachter, H., Jabbal, I., Hudgin, R.L., Pinteric, L., McGuire, E.J. and Roseman, S. Intracellular localization of liver sugar nucleotide glycoprotein glycosyltransferases in a Golgi-rich fraction. J. Biol. Chem. 245 (1970) 1090–1100. [PMID: 4392041]
[EC 2.4.1.90 created 1976 (EC 2.4.1.98 created 1980, incorporated 1984)]
 
 
EC 2.4.1.96     
Accepted name: sn-glycerol-3-phosphate 1-galactosyltransferase
Reaction: UDP-α-D-galactose + sn-glycerol 3-phosphate = UDP + 1-O-α-D-galactosyl-sn-glycerol 3-phosphate
Other name(s): isofloridoside-phosphate synthase; UDP-Gal:sn-glycero-3-phosphoric acid 1-α-galactosyl-transferase; UDPgalactose:sn-glycerol-3-phosphate α-D-galactosyltransferase; uridine diphosphogalactose-glycerol phosphate galactosyltransferase; glycerol 3-phosphate 1α-galactosyltransferase; UDP-galactose:sn-glycerol-3-phosphate 1-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:sn-glycerol-3-phosphate 1-α-D-galactosyltransferase
Comments: The product is hydrolysed by a phosphatase to isofloridoside, which is involved in osmoregulation (cf. EC 2.4.1.137 sn-glycerol-3-phosphate 2-α-galactosyltransferase).
References:
1.  Kauss, H. and Quader, H. In vitro activation of a galactosyl transferase involved in the osmotic regulation of Ochromonas. Plant Physiol. 58 (1976) 295–298. [PMID: 16659666]
2.  Kauss, H. and Schubert, B. `First demonstration of UDP-gal:sn-glycero-3-phosphoric acid 1α-galactosyl-transferase and its possible role in osmoregulation. FEBS Lett. 19 (1971) 131–135. [PMID: 11946194]
[EC 2.4.1.96 created 1978]
 
 
EC 2.4.1.98      
Deleted entry:  UDP-galactoseN-acetylglucosamine β-D-galactosyl-transferase. Now included with EC 2.4.1.90, N-acetyllactosamine synthase
[EC 2.4.1.98 created 1980, deleted 1984]
 
 
EC 2.4.1.122     
Accepted name: N-acetylgalactosaminide β-1,3-galactosyltransferase
Reaction: UDP-α-D-galactose + N-acetyl-α-D-galactosaminyl-R = UDP + β-D-galactosyl-(1→3)-N-acetyl-α-D-galactosaminyl-R
Other name(s): glycoprotein-N-acetylgalactosamine 3-β-galactosyltransferase; uridine diphosphogalactose-mucin β-(1→3)-galactosyltransferase; UDP-galactose:glycoprotein-N-acetyl-D-galactosamine 3-β-D-galactosyltransferase; UDP-Gal:α-D-GalNAc-1,3-α-D-GalNAc-diphosphoundecaprenol β-1,3-galactosyltransferase; wbnJ (gene name); wbiP (gene name); C1GALT1 (gene name); UDP-α-D-galactose:glycoprotein-N-acetyl-D-galactosamine 3-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:N-acetyl-α-D-galactosaminyl-R β-1,3-galactosyltransferase (configuration-inverting)
Comments: The eukaryotic enzyme can act on non-reducing O-serine-linked N-acetylgalactosamine residues in mucin glycoproteins, forming the T-antigen. The bacterial enzyme, found in some pathogenic strains, is involved in biosynthesis of the O-antigen repeating unit.
References:
1.  Hesford, F.J., Berger, E.G. and van den Eijnden, D.H. Identification of the product formed by human erythrocyte galactosyltransferase. Biochim. Biophys. Acta 659 (1981) 302–311. [PMID: 6789880]
2.  Mendicino, J., Sivakami, S., Davila, M. and Chandrasekaran, E.V. Purification and properties of UDP-gal:N-acetylgalactosaminide mucin:β1,3-galactosyltransferase from swine trachea mucosa. J. Biol. Chem. 257 (1982) 3987–3994. [PMID: 6801057]
3.  Schachter, H., Narasimhan, S., Gleeson, P. and Vella, G. Glycosyltransferases involved in elongation of N-glycosidically linked oligosaccharides of the complex or N-acetyllactosamine type. Methods Enzymol. 98 (1983) 98–134. [PMID: 6366476]
4.  Ju, T., Brewer, K., D'Souza, A., Cummings, R.D. and Canfield, W.M. Cloning and expression of human core 1 β1,3-galactosyltransferase. J. Biol. Chem. 277 (2002) 178–186. [PMID: 11677243]
5.  Yi, W., Perali, R.S., Eguchi, H., Motari, E., Woodward, R. and Wang, P.G. Characterization of a bacterial β-1,3-galactosyltransferase with application in the synthesis of tumor-associated T-antigen mimics. Biochemistry 47 (2008) 1241–1248. [PMID: 18179256]
6.  Woodward, R., Yi, W., Li, L., Zhao, G., Eguchi, H., Sridhar, P.R., Guo, H., Song, J.K., Motari, E., Cai, L., Kelleher, P., Liu, X., Han, W., Zhang, W., Ding, Y., Li, M. and Wang, P.G. In vitro bacterial polysaccharide biosynthesis: defining the functions of Wzy and Wzz. Nat. Chem. Biol. 6 (2010) 418–423. [PMID: 20418877]
[EC 2.4.1.122 created 1984 (EC 2.4.1.307 created 2013, incorporated 2016), modified 2016]
 
 
EC 2.4.1.123     
Accepted name: inositol 3-α-galactosyltransferase
Reaction: UDP-α-D-galactose + myo-inositol = UDP + O-α-D-galactosyl-(1→3)-1D-myo-inositol
Glossary: O-α-D-galactosyl-(1→3)-1D-myo-inositol = galactinol
Other name(s): UDP-D-galactose:inositol galactosyltransferase; UDP-galactose:myo-inositol 1-α-D-galactosyltransferase; UDPgalactose:myo-inositol 1-α-D-galactosyltransferase; galactinol synthase; inositol 1-α-galactosyltransferase; uridine diphosphogalactose-inositol galactosyltransferase; GolS; UDP-galactose:myo-inositol 3-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:myo-inositol 3-α-D-galactosyltransferase
Comments: An enzyme from plants involved in the formation of raffinose and stachyose [cf. EC 2.4.1.67 (galactinol—raffinose galactosyltransferase) and EC 2.4.1.82 (galactinol—sucrose galactosyltransferase)].
References:
1.  Pharr, D.M., Sox, H.N., Locy, R.D. and Huber, S.C. Partial characterization of the galactinol forming enzyme from leaves of Cucumis sativus L. Plant Sci. Lett. 23 (1981) 25–33.
[EC 2.4.1.123 created 1984, modified 2003]
 
 
EC 2.4.1.133     
Accepted name: xylosylprotein 4-β-galactosyltransferase
Reaction: UDP-α-D-galactose + [protein]-3-O-(β-D-xylosyl)-L-serine = UDP + [protein]-3-O-(β-D-galactosyl-(1→4)-β-D-xylosyl)-L-serine
Other name(s): UDP-D-galactose:D-xylose galactosyltransferase; UDP-D-galactose:xylose galactosyltransferase; galactosyltransferase I; uridine diphosphogalactose-xylose galactosyltransferase; UDP-galactose:O-β-D-xylosylprotein 4-β-D-galactosyltransferase; UDP-α-D-galactose:O-β-D-xylosylprotein 4-β-D-galactosyltransferase; UDP-α-D-galactose:O-β-D-xylosyl-[protein] 4-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:[protein]-3-O-(β-D-xylosyl)-L-serine 4-β-D-galactosyltransferase (configuration-inverting)
Comments: Involved in the biosynthesis of the linkage region of glycosaminoglycan chains as part of proteoglycan biosynthesis (chondroitin, dermatan and heparan sulfates). Requires Mn2+.
References:
1.  Schwartz, N.B. and Roden, L. Biosynthesis of chondroitin sulfate. Solubilization of chondroitin sulfate glycosyltransferases and partial purification of uridine diphosphate-D-galactose:D-xylose galactosyltransferase. J. Biol. Chem. 250 (1975) 5200–5207. [PMID: 1150655]
2.  Okajima, T., Yoshida, K., Kondo, T. and Furukawa, K. Human homolog of Caenorhabditis elegans sqv-3 gene is galactosyltransferase I involved in the biosynthesis of the glycosaminoglycan-protein linkage region of proteoglycans. J. Biol. Chem. 274 (1999) 22915–22918. [PMID: 10438455]
[EC 2.4.1.133 created 1984, modified 2002]
 
 
EC 2.4.1.134     
Accepted name: galactosylxylosylprotein 3-β-galactosyltransferase
Reaction: UDP-α-D-galactose + [protein]-3-O-(β-D-galactosyl-(1→4)-β-D-xylosyl)-L-serine = UDP + [protein]-3-O-(β-D-galactosyl-(1→3)-β-D-galactosyl-(1→4)-β-D-xylosyl)-L-serine
Other name(s): galactosyltransferase II; uridine diphosphogalactose-galactosylxylose galactosyltransferase; UDP-galactose:4-β-D-galactosyl-O-β-D-xylosylprotein 3-β-D-galactosyltransferase; UDP-α-D-galactose:4-β-D-galactosyl-O-β-D-xylosylprotein 3-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:[protein]-3-O-(β-D-galactosyl-(1→4)-β-D-xylosyl)-L-serine (configuration-inverting)
Comments: Involved in the biosynthesis of the linkage region of glycosaminoglycan chains as part of proteoglycan biosynthesis (chondroitin, dermatan and heparan sulfates). Requires Mn2+.
References:
1.  Robinson, J.A. and Robinson, H.C. Initiation of chondroitin sulphate synthesis by β-D-galactosides. Substrates for galactosyltransferase II. Biochem. J. 227 (1985) 805–814. [PMID: 3924029]
2.  Schwartz, N.B. and Roden, L. Biosynthesis of chondroitin sulfate. Solubilization of chondroitin sulfate glycosyltransferases and partial purification of uridine diphosphate-D-galactose:D-xylose galactosyltransferase. J. Biol. Chem. 250 (1975) 5200–5207. [PMID: 1150655]
3.  Bai, X., Zhou, D., Brown, J.R., Crawford, B.E., Hennet, T. and Esko, J.D. Biosynthesis of the linkage region of glycosaminoglycans: cloning and activity of galactosyltransferase II, the sixth member of the β1,3-galactosyltransferase family (β3GalT6). J. Biol. Chem. 276 (2001) 48189–48195. [PMID: 11551958]
[EC 2.4.1.134 created 1984, modified 2002]
 
 
EC 2.4.1.137     
Accepted name: sn-glycerol-3-phosphate 2-α-galactosyltransferase
Reaction: UDP-α-D-galactose + sn-glycerol 3-phosphate = UDP + 2-(α-D-galactosyl)-sn-glycerol 3-phosphate
Other name(s): floridoside-phosphate synthase; UDP-galactose:sn-glycerol-3-phosphate-2-D-galactosyl transferase; FPS; UDP-galactose,sn-3-glycerol phosphate:1→2′ galactosyltransferase; floridoside phosphate synthetase; floridoside phosphate synthase; UDP-galactose:sn-glycerol-3-phosphate 2-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:sn-glycerol-3-phosphate 2-α-D-galactosyltransferase
Comments: The product is hydrolysed by a phosphatase to floridoside (cf. EC 2.4.1.96 sn-glycerol-3-phosphate 1-galactosyltransferase).
References:
1.  Gray, N.C.C. and Strickland, K.P. The purification and characterization of a phospholipase A2 activity from the 106,000 x g pellet (microsomal fraction) of bovine brain acting on phosphatidylinositol. Can. J. Biochem. 60 (1982) 108–117. [PMID: 7083039]
[EC 2.4.1.137 created 1984]
 
 
EC 2.4.1.146     
Accepted name: β-1,3-galactosyl-O-glycosyl-glycoprotein β-1,3-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + 3-O-{β-D-galactosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→6)]-N-acetyl-α-D-galactosaminyl}-L-seryl/threonyl-[protein] = UDP + 3-O-{N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→6)]-N-acetyl-α-D-galactosaminyl}-L-seryl/threonyl-[protein]
Glossary: core 2 = 3-O-{β-D-galactosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→6)]-N-acetyl-α-D-galactosaminyl}-L-seryl/threonyl-[protein]
Other name(s): O-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase II; uridine diphosphoacetylglucosamine-mucin β(1→3)-acetylglucosaminyltransferase (elongating); elongation 3β-GalNAc-transferase; UDP-N-acetyl-D-glucosamine:O-glycosyl-glycoprotein (N-acetyl-D-glucosamine to β-D-galactose of β-D-galactosyl-1,3-(N-acetyl-D-glucosaminyl-1,6)-N-acetyl-D-galactosaminyl-R) β-1,3-N-acetyl-D-glucosaminyltransferase; UDP-N-acetyl-D-glucosamine:β-D-galactosyl-(1→3)-[N-acetyl-D-glucosaminyl-(1→6)]-N-acetyl-D-galactosaminyl-R 3-β-N-acetyl-D-glucosaminyltransferase; B3GNT3 (gene name)
Systematic name: UDP-N-acetyl-α-D-glucosamine:3-O-{β-D-galactosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→6)]-N-acetyl-α-D-galactosaminyl}-L-seryl/threonyl-[protein] 3-β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: The enzyme catalyses the addition of N-acetyl-α-D-glucosamine to the core 2 structure of O-glycans.
References:
1.  Brockhausen, I., Rachaman, E.S., Matta, K.L. and Schachter, H. The separation by liquid chromatography (under elevated pressure) of phenyl, benzyl, and O-nitrophenyl glycosides of oligosaccharides. Analysis of substrates and products for four N-acetyl-D-glucosaminyl-transferases involved in mucin synthesis. Carbohydr. Res. 120 (1983) 3–16. [PMID: 6226356]
2.  Shiraishi, N., Natsume, A., Togayachi, A., Endo, T., Akashima, T., Yamada, Y., Imai, N., Nakagawa, S., Koizumi, S., Sekine, S., Narimatsu, H. and Sasaki, K. Identification and characterization of three novel β 1,3-N-acetylglucosaminyltransferases structurally related to the β 1,3-galactosyltransferase family. J. Biol. Chem. 276 (2001) 3498–3507. [PMID: 11042166]
[EC 2.4.1.146 created 1984, modified 2018]
 
 
EC 2.4.1.149     
Accepted name: N-acetyllactosaminide β-1,3-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + β-D-galactosyl-(1→4)-N-acetyl-β-D-glucosaminyl-R = UDP + N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-N-acetyl-β-D-glucosaminyl-R
Other name(s): uridine diphosphoacetylglucosamine-acetyllactosaminide β1→3-acetylglucosaminyltransferase; poly-N-acetyllactosamine extension enzyme; Galβ1→4GlcNAc-R β1→3 N-acetylglucosaminyltransferase; UDP-GlcNAc:GalR β-D-3-N-acetylglucosaminyltransferase; N-acetyllactosamine β(1-3)N-acetylglucosaminyltransferase; UDP-GlcNAc:Galβ1→4GlcNAcβ-Rβ1→3-N-acetylglucosaminyltransferase; GnTE; UDP-N-acetyl-D-glucosamine:β-D-galactosyl-1,4-N-acetyl-D-glucosamine β-1,3-acetyl-D-glucosaminyltransferase; β-galactosyl-N-acetylglucosaminylgalactosylglucosyl-ceramide β-1,3-acetylglucosaminyltransferase; UDP-N-acetyl-D-glucosamine:β-D-galactosyl-(1→4)-N-acetyl-D-glucosamine 3-β-N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:β-D-galactosyl-(1→4)-N-acetyl-β-D-glucosaminyl-R 3-β N-acetylglucosaminyltransferase (configuration-inverting)
Comments: Acts on β-galactosyl-1,4-N-acetylglucosaminyl termini on glycoproteins, glycolipids, and oligosaccharides.
References:
1.  Van den Eijnden, D.H., Winterwerp, H., Smeeman, P. and Schiphorst, W.E.C.M. Novikoff ascites tumor cells contain N-acetyllactosaminide β1→3 and β1→6 N-acetylglucosaminyltransferase activity. J. Biol. Chem. 258 (1983) 3435–3437. [PMID: 6219989]
2.  Basu, M. and Basu, S. Biosynthesis in vitro of Ii core glycosphingolipids from neolactotetraosylceramide by β 1-3- and β 1-6-N-acetylglucosaminyltransferases from mouse T-lymphoma. J. Biol. Chem. 259 (1984) 12557–12562. [PMID: 6238026]
3.  Takeya, A., Hosomi, O. and Kogure, T. The presence of N-acetyllactosamine and lactose: β (1-3)N-acetylglucosaminyltransferase activity in human urine. Jpn. J. Med. Sci. Biol. 38 (1985) 1–8. [PMID: 3160874]
[EC 2.4.1.149 created 1984 (EC 2.4.1.163 created 1989, incorporated 2016), modified 2016]
 
 
EC 2.4.1.156     
Accepted name: indolylacetyl-myo-inositol galactosyltransferase
Reaction: UDP-α-D-galactose + (indol-3-yl)acetyl-myo-inositol = UDP + 5-O-(indol-3-yl)acetyl-myo-inositol D-galactoside
Other name(s): uridine diphosphogalactose-indolylacetylinositol galactosyltransferase; indol-3-ylacetyl-myo-inositol galactoside synthase; UDP-galactose:indol-3-ylacetyl-myo-inositol 5-O-D-galactosyltransferase; UDP-galactose:(indol-3-yl)acetyl-myo-inositol 5-O-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:(indol-3-yl)acetyl-myo-inositol 5-O-D-galactosyltransferase
References:
1.  Corcuera, L.J., Michalczuk, L. and Bandurski, R.S. Enzymic synthesis of indol-3-ylacetyl-myo-inositol galactoside. Biochem. J. 207 (1982) 283–290. [PMID: 7159382]
[EC 2.4.1.156 created 1986]
 
 
EC 2.4.1.167     
Accepted name: sucrose 6F-α-galactosyltransferase
Reaction: UDP-α-D-galactose + sucrose = UDP + 6F-α-D-galactosylsucrose
Other name(s): uridine diphosphogalactose-sucrose 6F-α-galactosyltransferase; UDPgalactose:sucrose 6fru-α-galactosyltransferase; sucrose 6F-α-galactotransferase; UDP-galactose:sucrose 6F-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:sucrose 6F-α-D-galactosyltransferase
Comments: The enzyme is involved in the synthesis of the trisaccharide planteose and higher analogues in the seeds of Plantago and Sesamum species.
References:
1.  Hopf, H., Spanfelner, M. and Kandler, O. Planteose synthesis in seeds of Sesamum indicum L. Z. Pflanzenphysiol. 114 (1984) 485–492.
[EC 2.4.1.167 created 1989]
 
 
EC 2.4.1.173     
Accepted name: sterol 3β-glucosyltransferase
Reaction: UDP-glucose + a sterol = UDP + a sterol 3-β-D-glucoside
Other name(s): UDPG:sterol glucosyltransferase; UDP-glucose-sterol β-glucosyltransferase; sterol:UDPG glucosyltransferase; UDPG-SGTase; uridine diphosphoglucose-poriferasterol glucosyltransferase; uridine diphosphoglucose-sterol glucosyltransferase; sterol glucosyltransferase; sterol-β-D-glucosyltransferase; UDP-glucose-sterol glucosyltransferase
Systematic name: UDP-glucose:sterol 3-O-β-D-glucosyltransferase
Comments: Not identical with EC 2.4.1.192 (nuatigenin 3β-glucosyltransferase) or EC 2.4.1.193 (sarsapogenin 3β-glucosyltransferase).
References:
1.  Duperon, R. and Duperon, P. Intracellular-localization of UDP-glucose-sterol glucosyl transferase and UDP-galactose-sterol galactosyl transferase activities in the leaves of tomato (Solanum lycopersicon L, Solanaceae). C.R. Acad. Sci. Paris, Ser. 3 304 (1987) 235–238.
2.  Kalinowska, M. and Wojciechowski, Z.A. Enzymatic-synthesis of nuatigenin 3-β-D-glucoside in oat (Avena sativa) leaves. Phytochemistry 25 (1986) 2525–2529.
3.  Kalinowska, M. and Wojciechowski, Z.A. Subcellular-localization of UDPG-nuatigenin glucosyltransferase in oat leaves. Phytochemistry 26 (1987) 353–357.
4.  Murakami-Murofushi, K. and Ohta, J. Expression of UDP-glucose: poriferasterol glucosyltransferase in the process of differentiation of a true slime mold, Physarum polycephalum. Biochim. Biophys. Acta 992 (1989) 412–415. [PMID: 2528379]
5.  Wojciechowski, Z.A., Zimowski, J. and Tyski, S. Enzymatic synthesis of steryl 3β-D-monoglucosides in the slime mold Physarum polycephalum. Phytochemistry 16 (1977) 911–914.
[EC 2.4.1.173 created 1989]
 
 
EC 2.4.1.179     
Accepted name: lactosylceramide β-1,3-galactosyltransferase
Reaction: UDP-α-D-galactose + β-D-galactosyl-(1→4)-β-D-glucosyl-R = UDP + β-D-galactosyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-R
Glossary: lactosylceramide = β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide
Other name(s): uridine diphosphogalactose-lactosylceramide β1→3-galactosyltransferase; UDP-galactose:D-galactosyl-1,4-β-D-glucosyl-R β-1,3-galactosyltransferase; UDP-galactose:D-galactosyl-(1→4)-β-D-glucosyl-R 3-β-galactosyltransferase; UDP-α-D-galactose:D-galactosyl-(1→4)-β-D-glucosyl-R 3-β-galactosyltransferase
Systematic name: UDP-α-D-galactose:β-D-galactosyl-(1→4)-β-D-glucosyl-R 3-β-galactosyltransferase
Comments: R may be an oligosaccharide or a glycolipid; lactose can also act as acceptor, but more slowly. Involved in the elongation of oligosaccharide chains, especially in glycolipids.
References:
1.  Bailly, P., Piller, F. and Cartron, J.-P. Characterization and specific assay for a galactoside β-3-galactosyltransferase of human kidney. Eur. J. Biochem. 173 (1988) 417–422. [PMID: 3129295]
[EC 2.4.1.179 created 1989]
 
 
EC 2.4.1.184     
Accepted name: galactolipid galactosyltransferase
Reaction: 2 a 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol = a 1,2-diacyl-3-O-[β-D-galactosyl-(1→6)-β-D-galactosyl]-sn-glycerol + a 1,2-diacyl-sn-glycerol
Glossary: a 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol = monogalactosyldiacylglycerol
Other name(s): galactolipid-galactolipid galactosyltransferase; galactolipid:galactolipid galactosyltransferase; interlipid galactosyltransferase; GGGT; DGDG synthase (ambiguous); digalactosyldiacylglycerol synthase (ambiguous); 3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol:mono-3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol β-D-galactosyltransferase; 3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol:3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol β-D-galactosyltransferase; SFR2 (gene name)
Systematic name: 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol:1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol β-D-galactosyltransferase
Comments: The enzyme converts monogalactosyldiacylglycerol to digalactosyldiacylglycerol, trigalactosyldiacylglycerol and tetragalactosyldiacylglycerol. All residues are connected by β linkages. The activity is localized to chloroplast envelope membranes, but it does not contribute to net galactolipid synthesis in plants, which is performed by EC 2.4.1.46, monogalactosyldiacylglycerol synthase, and EC 2.4.1.241, digalactosyldiacylglycerol synthase. Note that the β,β-digalactosyldiacylglycerol formed by this enzyme is different from the more common α,β-digalactosyldiacylglycerol formed by EC 2.4.1.241. The enzyme provides an important mechanism for the stabilization of the chloroplast membranes during freezing and drought stress.
References:
1.  Dorne, A.-J., Block, M.A., Joyard, J. and Douce, R. The galactolipid-galactolipid galactosyltransferase is located on the outer surface of the outer-membrane of the chloroplast envelope. FEBS Lett. 145 (1982) 30–34.
2.  Heemskerk, J.W.M., Wintermans, J.F.G.M., Joyard, J., Block, M.A., Dorne, A.-J. and Douce, R. Localization of galactolipid:galactolipid galactosyltransferase and acyltransferase in outer envelope membrane of spinach chloroplasts. Biochim. Biophys. Acta 877 (1986) 281–289.
3.  Heemskerk, J.W.M., Jacobs, F.H.H. and Wintermans, J.F.G.M. UDPgalactose-independent synthesis of monogalactosyldiacylglycerol. An enzymatic activity of the spinach chloroplast envelope. Biochim. Biophys. Acta 961 (1988) 38–47.
4.  Kelly, A.A., Froehlich, J.E. and Dörmann, P. Disruption of the two digalactosyldiacylglycerol synthase genes DGD1 and DGD2 in Arabidopsis reveals the existence of an additional enzyme of galactolipid synthesis. Plant Cell 15 (2003) 2694–2706. [PMID: 14600212]
5.  Benning, C. and Ohta, H. Three enzyme systems for galactoglycerolipid biosynthesis are coordinately regulated in plants. J. Biol. Chem. 280 (2005) 2397–2400. [PMID: 15590685]
6.  Fourrier, N., Bedard, J., Lopez-Juez, E., Barbrook, A., Bowyer, J., Jarvis, P., Warren, G. and Thorlby, G. A role for SENSITIVE TO FREEZING2 in protecting chloroplasts against freeze-induced damage in Arabidopsis. Plant J. 55 (2008) 734–745. [PMID: 18466306]
7.  Moellering, E.R., Muthan, B. and Benning, C. Freezing tolerance in plants requires lipid remodeling at the outer chloroplast membrane. Science 330 (2010) 226–228. [PMID: 20798281]
[EC 2.4.1.184 created 1990, modified 2005, modified 2015]
 
 
EC 2.4.1.205     
Accepted name: galactogen 6β-galactosyltransferase
Reaction: UDP-α-D-galactose + galactogen = UDP + (1→6)-β-D-galactosylgalactogen
Other name(s): uridine diphosphogalactose-galactogen galactosyltransferase; 1,6-D-galactosyltransferase; β-(1-6)-D-galactosyltransferase; UDP-galactose:galactogen β-1,6-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:galactogen 6-β-D-galactosyltransferase
Comments: Galactogen from Helix pomatia is the most effective acceptor.
References:
1.  Goudsmit, E.M., Ketchum, P.A., Grossens, M.K. and Blake, D.A. Biosynthesis of galactogen: identification of a β-(1→6)-D-galactosyltransferase in Helix pomatia albumen glands. Biochim. Biophys. Acta 992 (1989) 289–297. [PMID: 2505854]
[EC 2.4.1.205 created 1992]
 
 
EC 2.4.1.228     
Accepted name: lactosylceramide 4-α-galactosyltransferase
Reaction: UDP-α-D-galactose + β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide = UDP + α-D-galactosyl-(1→4)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide
Glossary: lactosylceramide = β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide
Other name(s): Galβ1-4Glcβ1-Cer α1,4-galactosyltransferase; globotriaosylceramide/CD77 synthase; histo-blood group Pk UDP-galactose; UDP-galactose:lactosylceramide 4II-α-D-galactosyltransferase; UDP-galactose:β-D-galactosyl-(1→4)-D-glucosyl(1↔1)ceramide 4II-α-D-galactosyltransferase; UDP-galactose:β-D-galactosyl-(1→4)-D-glucosyl-(1↔1)-ceramide 4II-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:β-D-galactosyl-(1→4)-D-glucosyl-(1↔1)-ceramide 4II-α-D-galactosyltransferase
Comments: For explanation of superscript II in systematic name, see 2-carb.37.
References:
1.  Bailly, P., Piller, F., Cartron, J.P., Leroy, Y. and Fournet, B. Identification of UDP-galactose: lactose (lactosylceramide) α-4 and β-3 galactosyltransferases in human kidney. Biochem. Biophys. Res. Commun. 141 (1986) 84–91. [PMID: 3099784]
2.  Steffensen, R., Carlier, K., Wiels, J., Levery, S.B., Stroud, M., Cedergren, B., Nilsson Sojka, B., Bennett, E.P., Jersild, C. and Clausen, H. Cloning and expression of the histo-blood group Pk UDP-galactose: Galβ1-4Glcβ1-Cer α1,4-galactosyltransferase. Molecular genetic basis of the p phenotype. J. Biol. Chem. 275 (2000) 16723–16729. [PMID: 10747952]
3.  Kojima, Y., Fukumoto, S., Furukawa, K., Okajima, T., Wiels, J., Yokoyama, K., Suzuki, Y., Urano, T., Ohta, M. and Furukawa, K. Molecular cloning of globotriaosylceramide/CD77 synthase, a glycosyltransferase that initiates the synthesis of globo series glycosphingolipids. J. Biol. Chem. 275 (2000) 15152–15156. [PMID: 10748143]
[EC 2.4.1.228 created 2002]
 
 
EC 2.4.1.230     
Accepted name: kojibiose phosphorylase
Reaction: 2-α-D-glucosyl-D-glucose + phosphate = D-glucose + β-D-glucose 1-phosphate
Systematic name: 2-α-D-glucosyl-D-glucose:phosphate β-D-glucosyltransferase
Comments: The enzyme from Thermoanaerobacter brockii can act with α-1,2-oligoglucans, such as selaginose, as substrate, but more slowly. The enzyme is inactive when dissaccharides with linkages other than α-1,2 linkages, such as sophorose, trehalose, neotrehalose, nigerose, laminaribiose, maltose, cellobiose, isomaltose, gentiobiose, sucrose and lactose, are used as substrates.
References:
1.  Chaen, H., Yamamoto, T., Nishimoto, T., Nakada, T., Fukuda, S., Sugimoto, T., Kurimoto, M. and Tsujisaka, Y. Purification and characterization of a novel phosphorylase, kojibiose phosphorylase, from Thermoanaerobium brockii. J. Appl. Glycosci. 46 (1999) 423–429.
2.  Chaen, H., Nishimoto, T., Nakada, T., Fukuda, S., Kurimoto, M. and Tsujisaka, Y. Enzymatic synthesis of kojioligosaccharides using kojibiose phosphorylase. J. Biosci. Bioeng. 92 (2001) 177–182. [PMID: 16233080]
[EC 2.4.1.230 created 2003]
 
 
EC 2.4.1.234     
Accepted name: kaempferol 3-O-galactosyltransferase
Reaction: UDP-α-D-galactose + kaempferol = UDP + kaempferol 3-O-β-D-galactoside
Other name(s): F3GalTase; UDP-galactose:kaempferol 3-O-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:kaempferol 3-O-β-D-galactosyltransferase
Comments: Acts on the endogenous flavonols kaempferol and quercetin, to a lesser extent on myricetin and fisetin, and weakly on galangin and isorhamnetin. The reaction can occur equally well in both directions.
References:
1.  Miller, K.D., Guyon, V., Evans, J.N., Shuttleworth, W.A. and Taylor, L.P. Purification, cloning, and heterologous expression of a catalytically efficient flavonol 3-O-galactosyltransferase expressed in the male gametophyte of Petunia hybrida. J. Biol. Chem. 274 (1999) 34011–34019. [PMID: 10567367]
[EC 2.4.1.234 created 2004]
 
 
EC 2.4.1.241     
Accepted name: digalactosyldiacylglycerol synthase
Reaction: UDP-α-D-galactose + 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol = UDP + 1,2-diacyl-3-O-[α-D-galactosyl-(1→6)-β-D-galactosyl]-sn-glycerol
Other name(s): DGD1; DGD2; DGDG synthase (ambiguous); UDP-galactose-dependent DGDG synthase; UDP-galactose-dependent digalactosyldiacylglycerol synthase; UDP-galactose:MGDG galactosyltransferase; UDP-galactose:3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol 6-α-galactosyltransferase
Systematic name: UDP-α-D-galactose:1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol 6-α-galactosyltransferase
Comments: Requires Mg2+. Diacylglycerol cannot serve as an acceptor molecule for galactosylation as in the reaction catalysed by EC 2.4.1.46, monogalactosyldiacylglyerol synthase. When phosphate is limiting, phospholipids in plant membranes are reduced but these are replaced, at least in part, by the glycolipids digalactosyldiacylglycerol (DGDG) and sulfoquinovosyldiacylglycerol [3]. While both DGD1 and DGD2 are increased under phosphate-limiting conditions, DGD2 does not contribute significantly under optimal growth conditions. DGD2 is responsible for the synthesis of DGDG molecular species that are rich in C16 fatty acids at sn-1 of diacylglycerol whereas DGD1 leads to molecular species rich in C18 fatty acids [3]. The enzyme has been localized to the outer side of chloroplast envelope membranes.
References:
1.  Kelly, A.A. and Dörmann, P. DGD2, an Arabidopsis gene encoding a UDP-galactose-dependent digalactosyldiacylglycerol synthase is expressed during growth under phosphate-limiting conditions. J. Biol. Chem. 277 (2002) 1166–1173. [PMID: 11696551]
2.  Härtel, H., Dörmann, P. and Benning, C. DGD1-independent biosynthesis of extraplastidic galactolipids after phosphate deprivation in Arabidopsis. Proc. Natl. Acad. Sci. USA 97 (2000) 10649–10654. [PMID: 10973486]
3.  Kelly, A.A., Froehlich, J.E. and Dörmann, P. Disruption of the two digalactosyldiacylglycerol synthase genes DGD1 and DGD2 in Arabidopsis reveals the existence of an additional enzyme of galactolipid synthesis. Plant Cell 15 (2003) 2694–2706. [PMID: 14600212]
4.  Benning, C. and Ohta, H. Three enzyme systems for galactoglycerolipid biosynthesis are coordinately regulated in plants. J. Biol. Chem. 280 (2005) 2397–2400. [PMID: 15590685]
[EC 2.4.1.241 created 2005]
 
 
EC 2.4.1.244     
Accepted name: N-acetyl-β-glucosaminyl-glycoprotein 4-β-N-acetylgalactosaminyltransferase
Reaction: UDP-N-acetyl-α-D-galactosamine + N-acetyl-β-D-glucosaminyl group = UDP + N-acetyl-β-D-galactosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl group
Glossary: N-acetyl-β-D-galactosaminyl-(1→4)-N-acetyl-β-D-glucosamine = N,N′-diacetyllactosediamine
Other name(s): β1,4-N-acetylgalactosaminyltransferase III; β4GalNAc-T3; β1,4-N-acetylgalactosaminyltransferase IV; β4GalNAc-T4; UDP-N-acetyl-D-galactosamine:N-acetyl-D-glucosaminyl-group β-1,4-N-acetylgalactosaminyltransferase; UDP-N-acetyl-D-galactosamine:N-acetyl-β-D-glucosaminyl-group 4-β-N-acetylgalactosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-galactosamine:N-acetyl-β-D-glucosaminyl-group 4-β-N-acetylgalactosaminyltransferase
Comments: The enzyme from human can transfer N-acetyl-D-galactosamine (GalNAc) to N-glycan and O-glycan substrates that have N-acetyl-D-glucosamine (GlcNAc) but not D-glucuronic acid (GlcUA) at their non-reducing end. The N-acetyl-β-D-glucosaminyl group is normally on a core oligosaccharide although benzyl glycosides have been used in enzyme-characterization experiments. Some glycohormones, e.g. lutropin and thyrotropin contain the N-glycan structure containing the N-acetyl-β-D-galactosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl group.
References:
1.  Sato, T., Gotoh, M., Kiyohara, K., Kameyama, A., Kubota, T., Kikuchi, N., Ishizuka, Y., Iwasaki, H., Togayachi, A., Kudo, T., Ohkura, T., Nakanishi, H. and Narimatsu, H. Molecular cloning and characterization of a novel human β1,4-N-acetylgalactosaminyltransferase, β4GalNAc-T3, responsible for the synthesis of N,N'-diacetyllactosediamine, GalNAc β1-4GlcNAc. J. Biol. Chem. 278 (2003) 47534–47544. [PMID: 12966086]
2.  Gotoh, M., Sato, T., Kiyohara, K., Kameyama, A., Kikuchi, N., Kwon, Y.D., Ishizuka, Y., Iwai, T., Nakanishi, H. and Narimatsu, H. Molecular cloning and characterization of β1,4-N-acetylgalactosaminyltransferases IV synthesizing N,N'-diacetyllactosediamine. FEBS Lett. 562 (2004) 134–140. [PMID: 15044014]
[EC 2.4.1.244 created 2006]
 
 
EC 2.4.1.245     
Accepted name: α,α-trehalose synthase
Reaction: NDP-α-D-glucose + D-glucose = α,α-trehalose + NDP
Glossary: NDP = a nucleoside diphosphate
Other name(s): trehalose synthase; trehalose synthetase; UDP-glucose:glucose 1-glucosyltransferase; TreT; PhGT; ADP-glucose:D-glucose 1-α-D-glucosyltransferase
Systematic name: NDP-α-D-glucose:D-glucose 1-α-D-glucosyltransferase
Comments: Requires Mg2+ for maximal activity [1]. The enzyme-catalysed reaction is reversible [1]. In the reverse direction to that shown above, the enzyme is specific for α,α-trehalose as substrate, as it cannot use α- or β-paranitrophenyl glucosides, maltose, sucrose, lactose or cellobiose [1]. While the enzymes from the thermophilic bacterium Rubrobacter xylanophilus and the hyperthermophilic archaeon Pyrococcus horikoshii can use ADP-, UDP- and GDP-α-D-glucose to the same extent [2,3], that from the hyperthermophilic archaeon Thermococcus litoralis has a marked preference for ADP-α-D-glucose [1] and that from the hyperthermophilic archaeon Thermoproteus tenax has a marked preference for UDP-α-D-glucose [4].
References:
1.  Qu, Q., Lee, S.J. and Boos, W. TreT, a novel trehalose glycosyltransferring synthase of the hyperthermophilic archaeon Thermococcus litoralis. J. Biol. Chem. 279 (2004) 47890–47897. [PMID: 15364950]
2.  Ryu, S.I., Park, C.S., Cha, J., Woo, E.J. and Lee, S.B. A novel trehalose-synthesizing glycosyltransferase from Pyrococcus horikoshii: molecular cloning and characterization. Biochem. Biophys. Res. Commun. 329 (2005) 429–436. [PMID: 15737605]
3.  Nobre, A., Alarico, S., Fernandes, C., Empadinhas, N. and da Costa, M.S. A unique combination of genetic systems for the synthesis of trehalose in Rubrobacter xylanophilus: properties of a rare actinobacterial TreT. J. Bacteriol. 190 (2008) 7939–7946. [PMID: 18835983]
4.  Kouril, T., Zaparty, M., Marrero, J., Brinkmann, H. and Siebers, B. A novel trehalose synthesizing pathway in the hyperthermophilic Crenarchaeon Thermoproteus tenax: the unidirectional TreT pathway. Arch. Microbiol. 190 (2008) 355–369. [PMID: 18483808]
[EC 2.4.1.245 created 2008, modified 2013]
 
 
EC 2.4.1.247     
Accepted name: β-D-galactosyl-(1→4)-L-rhamnose phosphorylase
Reaction: β-D-galactosyl-(1→4)-L-rhamnose + phosphate = L-rhamnose + α-D-galactose 1-phosphate
Other name(s): D-galactosyl-β1→4-L-rhamnose phosphorylase; GalRhaP
Systematic name: β-D-galactosyl-(1→4)-L-rhamnose:phosphate 1-α-D-galactosyltransferase
Comments: The enzyme from Clostridium phytofermentans is also active towards towards β-D-galactosyl derivatives of L-mannose, L-lyxose, D-glucose, 2-deoxy-D-glucose, and D-galactose in this order. Differs from 1,3-β-galactosyl-N-acetylhexosamine phosphorylase (EC 2.4.1.211) in being active towards L-rhamnose and inactive towards N-acetyl hexosamine derivatives.
References:
1.  Nakajima, M., Nishimoto, M. and Kitaoka, M. Characterization of three β-galactoside phosphorylases from Clostridium phytofermentans: discovery of D-galactosyl-β1→4-L-rhamnose phosphorylase. J. Biol. Chem. 284 (2009) 19220–19227. [PMID: 19491100]
[EC 2.4.1.247 created 2009]
 
 
EC 2.4.1.272     
Accepted name: soyasapogenol B glucuronide galactosyltransferase
Reaction: UDP-α-D-galactose + soyasapogenol B 3-O-β-D-glucuronide = UDP + soyasaponin III
Glossary: soyasaponin III = 3β-(2-O-β-D-galactopyranosyl-β-D-glucopyranosyloxyuronic acid)olean-12-ene-22β,24-diol
Other name(s): UDP-galactose:SBMG-galactosyltransferase; UGT73P2; GmSGT2 (gene name); UDP-galactose:soyasapogenol B 3-O-glucuronide β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:soyasapogenol B 3-O-glucuronide β-D-galactosyltransferase
Comments: Part of the biosynthetic pathway for soyasaponins.
References:
1.  Shibuya, M., Nishimura, K., Yasuyama, N. and Ebizuka, Y. Identification and characterization of glycosyltransferases involved in the biosynthesis of soyasaponin I in Glycine max. FEBS Lett. 584 (2010) 2258–2264. [PMID: 20350545]
[EC 2.4.1.272 created 2011]
 
 
EC 2.4.1.274     
Accepted name: glucosylceramide β-1,4-galactosyltransferase
Reaction: UDP-α-D-galactose + β-D-glucosyl-(1↔1)-ceramide = UDP + β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide
Other name(s): lactosylceramide synthase; uridine diphosphate-galactose:glucosyl ceramide β 1-4 galactosyltransferase; UDP-Gal:glucosylceramide β1→4galactosyltransferase; GalT-2 (misleading); UDP-galactose:β-D-glucosyl-(1↔1)-ceramide β-1,4-galactosyltransferase
Systematic name: UDP-α-D-galactose:β-D-glucosyl-(1↔1)-ceramide 4-β-D-galactosyltransferase
Comments: Involved in the synthesis of several different major classes of glycosphingolipids.
References:
1.  Chatterjee, S. and Castiglione, E. UDPgalactose:glucosylceramide β1→4-galactosyltransferase activity in human proximal tubular cells from normal and familial hypercholesterolemic homozygotes. Biochim. Biophys. Acta 923 (1987) 136–142. [PMID: 3099851]
2.  Trinchera, M., Fiorilli, A. and Ghidoni, R. Localization in the Golgi apparatus of rat liver UDP-Gal:glucosylceramide β1→4galactosyltransferase. Biochemistry 30 (1991) 2719–2724. [PMID: 1900430]
3.  Chatterjee, S., Ghosh, N. and Khurana, S. Purification of uridine diphosphate-galactose:glucosyl ceramide, β 1-4 galactosyltransferase from human kidney. J. Biol. Chem. 267 (1992) 7148–7153. [PMID: 1551920]
4.  Nomura, T., Takizawa, M., Aoki, J., Arai, H., Inoue, K., Wakisaka, E., Yoshizuka, N., Imokawa, G., Dohmae, N., Takio, K., Hattori, M. and Matsuo, N. Purification, cDNA cloning, and expression of UDP-Gal: glucosylceramide β-1,4-galactosyltransferase from rat brain. J. Biol. Chem. 273 (1998) 13570–13577. [PMID: 9593693]
5.  Takizawa, M., Nomura, T., Wakisaka, E., Yoshizuka, N., Aoki, J., Arai, H., Inoue, K., Hattori, M. and Matsuo, N. cDNA cloning and expression of human lactosylceramide synthase. Biochim. Biophys. Acta 1438 (1999) 301–304. [PMID: 10320813]
[EC 2.4.1.274 created 2011]
 
 
EC 2.4.1.275     
Accepted name: neolactotriaosylceramide β-1,4-galactosyltransferase
Reaction: UDP-α-D-galactose + N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide = UDP + β-D-galactosyl-(1→4)-N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide
Glossary: N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide = neolactotriaosylceramide
Other name(s): β4Gal-T4; UDP-galactose:N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide β-1,4-galactosyltransferase; lactotriaosylceramide β-1,4-galactosyltransferase (incorrect)
Systematic name: UDP-α-D-galactose:N-acetyl-β-D-glucosaminyl-(1→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide 4-β-D-galactosyltransferase
References:
1.  Schwientek, T., Almeida, R., Levery, S.B., Holmes, E.H., Bennett, E. and Clausen, H. Cloning of a novel member of the UDP-galactose:β-N-acetylglucosamine β1,4-galactosyltransferase family, β4Gal-T4, involved in glycosphingolipid biosynthesis. J. Biol. Chem. 273 (1998) 29331–29340. [PMID: 9792633]
[EC 2.4.1.275 created 2011, modified 2013]
 
 
EC 2.4.1.280     
Accepted name: N,N′-diacetylchitobiose phosphorylase
Reaction: N,N′-diacetylchitobiose + phosphate = N-acetyl-D-glucosamine + N-acetyl-α-D-glucosamine 1-phosphate
Glossary: N,N′-diacetylchitobiose = N-acetyl-D-glucosaminyl-β-(1→4)-N-acetyl-D-glucosamine
Other name(s): chbP (gene name)
Systematic name: N,N′-diacetylchitobiose:phosphate N-acetyl-D-glucosaminyltransferase
Comments: The enzyme is specific for N,N′-diacetylchitobiose and does not phosphorylate other N-acetylchitooligosaccharides, cellobiose, trehalose, lactose, maltose or sucrose.
References:
1.  Park, J.K., Keyhani, N.O. and Roseman, S. Chitin catabolism in the marine bacterium Vibrio furnissii. Identification, molecular cloning, and characterization of a N,N′-diacetylchitobiose phosphorylase. J. Biol. Chem. 275 (2000) 33077–33083. [PMID: 10913116]
2.  Honda, Y., Kitaoka, M. and Hayashi, K. Reaction mechanism of chitobiose phosphorylase from Vibrio proteolyticus: identification of family 36 glycosyltransferase in Vibrio. Biochem. J. 377 (2004) 225–232. [PMID: 13678418]
3.  Hidaka, M., Honda, Y., Kitaoka, M., Nirasawa, S., Hayashi, K., Wakagi, T., Shoun, H. and Fushinobu, S. Chitobiose phosphorylase from Vibrio proteolyticus, a member of glycosyl transferase family 36, has a clan GH-L-like (α/α)6 barrel fold. Structure 12 (2004) 937–947. [PMID: 15274915]
[EC 2.4.1.280 created 2012]
 
 
EC 2.4.1.294     
Accepted name: cyanidin 3-O-galactosyltransferase
Reaction: UDP-α-D-galactose + cyanidin = UDP + cyanidin 3-O-β-D-galactoside
Glossary: cyanidin = 3,3′,4′,5,7-pentahydroxyflavylium
Other name(s): UDP-galactose:cyanidin galactosyltransferase
Systematic name: UDP-α-D-galactose:cyanidin 3-O-galactosyltransferase
Comments: Isolated from the plant Daucus carota (Afghan cultivar carrot).
References:
1.  Rose, A., Glassgen, W.E., Hopp, W. and Seitz, H.U. Purification and characterization of glycosyltransferases involved in anthocyanin biosynthesis in cell-suspension cultures of Daucus carota L. Planta 198 (1996) 397–403. [PMID: 8717136]
[EC 2.4.1.294 created 2013]
 
 
EC 2.4.1.303     
Accepted name: UDP-Gal:α-D-GlcNAc-diphosphoundecaprenol β-1,3-galactosyltransferase
Reaction: UDP-α-D-galactose + N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol = UDP + β-D-Gal-(1→3)-α-D-GlcNAc-diphospho-ditrans,octacis-undecaprenol
Other name(s): WbbD; WbbD β3Gal-transferase; UDP-Gal:GlcNAc-R β1,3-galactosyltransferase; UDP-Gal:GlcNAcα-pyrophosphate-R β1,3-galactosyltransferase; UDP-Gal:GlcNAc-R galactosyltransferase
Systematic name: UDP-α-D-galactose:N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol 3-β-galactosyltransferase (configuration-inverting)
Comments: The enzyme is involved in the the biosynthesis of the O-antigen repeating unit of Escherichia coli O7:K1 (VW187). Requires Mn2+. cf. EC 2.4.1.343, UDP-Gal:α-D-GlcNAc-diphosphoundecaprenol α-1,3-galactosyltransferase.
References:
1.  Riley, J.G., Menggad, M., Montoya-Peleaz, P.J., Szarek, W.A., Marolda, C.L., Valvano, M.A., Schutzbach, J.S. and Brockhausen, I. The wbbD gene of E. coli strain VW187 (O7:K1) encodes a UDP-Gal: GlcNAcα-pyrophosphate-R β1,3-galactosyltransferase involved in the biosynthesis of O7-specific lipopolysaccharide. Glycobiology 15 (2005) 605–613. [PMID: 15625181]
2.  Brockhausen, I., Riley, J.G., Joynt, M., Yang, X. and Szarek, W.A. Acceptor substrate specificity of UDP-Gal: GlcNAc-R β1,3-galactosyltransferase (WbbD) from Escherichia coli O7:K1. Glycoconj. J. 25 (2008) 663–673. [PMID: 18536883]
[EC 2.4.1.303 created 2013, modified 2017]
 
 
EC 2.4.1.304     
Accepted name: UDP-Gal:α-D-GlcNAc-diphosphoundecaprenol β-1,4-galactosyltransferase
Reaction: UDP-α-D-galactose + N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol = UDP + β-D-Gal-(1→4)-α-D-GlcNAc-diphospho-ditrans,octacis-undecaprenol
Other name(s): WfeD; UDP-Gal:GlcNAc-R 1,4-Gal-transferase; UDP-Gal:GlcNAc-pyrophosphate-lipid β-1,4-galactosyltransferase
Systematic name: UDP-α-D-galactose:N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol β-1,4-galactosyltransferase
Comments: The enzyme is involved in the the biosynthesis of the O-polysaccharide repeating unit of the bacterium Shigella boydii B14. The activity is stimulated by Mn2+ or to a lesser extent by Mg2+, Ca2+, Ni2+ or Pb2+.
References:
1.  Xu, C., Liu, B., Hu, B., Han, Y., Feng, L., Allingham, J.S., Szarek, W.A., Wang, L. and Brockhausen, I. Biochemical characterization of UDP-Gal:GlcNAc-pyrophosphate-lipid β-1,4-Galactosyltransferase WfeD, a new enzyme from Shigella boydii type 14 that catalyzes the second step in O-antigen repeating-unit synthesis. J. Bacteriol. 193 (2011) 449–459. [PMID: 21057010]
[EC 2.4.1.304 created 2013]
 
 
EC 2.4.1.307      
Deleted entry: UDP-Gal:α-D-GalNAc-1,3-α-D-GalNAc-diphosphoundecaprenol β-1,3-galactosyltransferase. Now included in EC 2.4.1.122, glycoprotein-N-acetylgalactosamine β-1,3-galactosyltransferase
[EC 2.4.1.307 created 2013, deleted 2016]
 
 
EC 2.4.1.309     
Accepted name: UDP-Gal:α-L-Fuc-1,2-β-Gal-1,3-α-GalNAc-1,3-α-GalNAc-diphosphoundecaprenol α-1,3-galactosyltransferase
Reaction: UDP-α-D-galactose + α-L-Fuc-(1→2)-β-D-Gal-(1→3)-α-D-GalNAc-(1→3)-α-D-GalNAc-diphospho-ditrans,octacis-undecaprenol = UDP + α-D-Gal-(1→3)-(α-L-Fuc-(1→2))-β-D-Gal-(1→3)-α-D-GalNAc-(1→3)-α-D-GalNAc-diphospho-ditrans,octacis-undecaprenol
Other name(s): WbnI
Systematic name: UDP-α-D-galactose:α-L-Fuc-(1→2)-β-D-Gal-(1→3)-α-D-GalNAc-(1→3)-α-D-GalNAc-diphospho-ditrans,octacis-undecaprenol α-1,3-galactosyltransferase
Comments: The enzyme is involved in the the biosynthesis of the O-polysaccharide repeating unit of the bacterium Escherichia coli serotype O86.
References:
1.  Yi, W., Shao, J., Zhu, L., Li, M., Singh, M., Lu, Y., Lin, S., Li, H., Ryu, K., Shen, J., Guo, H., Yao, Q., Bush, C.A. and Wang, P.G. Escherichia coli O86 O-antigen biosynthetic gene cluster and stepwise enzymatic synthesis of human blood group B antigen tetrasaccharide. J. Am. Chem. Soc. 127 (2005) 2040–2041. [PMID: 15713070]
2.  Yi, W., Zhu, L., Guo, H., Li, M., Li, J. and Wang, P.G. Formation of a new O-polysaccharide in Escherichia coli O86 via disruption of a glycosyltransferase gene involved in O-unit assembly. Carbohydr. Res. 341 (2006) 2254–2260. [PMID: 16839526]
3.  Woodward, R., Yi, W., Li, L., Zhao, G., Eguchi, H., Sridhar, P.R., Guo, H., Song, J.K., Motari, E., Cai, L., Kelleher, P., Liu, X., Han, W., Zhang, W., Ding, Y., Li, M. and Wang, P.G. In vitro bacterial polysaccharide biosynthesis: defining the functions of Wzy and Wzz. Nat. Chem. Biol. 6 (2010) 418–423. [PMID: 20418877]
[EC 2.4.1.309 created 2013]
 
 
EC 2.4.1.315     
Accepted name: diglucosyl diacylglycerol synthase (1,6-linking)
Reaction: (1) UDP-α-D-glucose + 1,2-diacyl-3-O-(β-D-glucopyranosyl)-sn-glycerol = 1,2-diacyl-3-O-[β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]-sn-glycerol + UDP
(2) UDP-α-D-glucose + 1,2-diacyl-3-O-[β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]-sn-glycerol = 1,2-diacyl-3-O-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]-sn-glycerol + UDP
Other name(s): monoglucosyl diacylglycerol (1→6) glucosyltransferase; MGlcDAG (1→6) glucosyltransferase; DGlcDAG synthase (ambiguous); UGT106B1; ypfP (gene name)
Systematic name: UDP-α-D-glucose:1,2-diacyl-3-O-(β-D-glucopyranosyl)-sn-glycerol 6-glucosyltransferase
Comments: The enzyme is found in several bacterial species. The enzyme from Bacillus subtilis is specific for glucose [1]. The enzyme from Mycoplasma genitalium can incoporate galactose with similar efficiency, but forms mainly 1,2-diacyl-diglucopyranosyl-sn-glycerol in vivo [3]. The enzyme from Staphylococcus aureus can also form glucosyl-glycero-3-phospho-(1′-sn-glycerol) [2].
References:
1.  Jorasch, P., Wolter, F.P., Zahringer, U. and Heinz, E. A UDP glucosyltransferase from Bacillus subtilis successively transfers up to four glucose residues to 1,2-diacylglycerol: expression of ypfP in Escherichia coli and structural analysis of its reaction products. Mol. Microbiol. 29 (1998) 419–430. [PMID: 9720862]
2.  Jorasch, P., Warnecke, D.C., Lindner, B., Zahringer, U. and Heinz, E. Novel processive and nonprocessive glycosyltransferases from Staphylococcus aureus and Arabidopsis thaliana synthesize glycoglycerolipids, glycophospholipids, glycosphingolipids and glycosylsterols. Eur. J. Biochem. 267 (2000) 3770–3783. [PMID: 10848996]
3.  Andres, E., Martinez, N. and Planas, A. Expression and characterization of a Mycoplasma genitalium glycosyltransferase in membrane glycolipid biosynthesis: potential target against mycoplasma infections. J. Biol. Chem. 286 (2011) 35367–35379. [PMID: 21835921]
[EC 2.4.1.315 created 2014]
 
 
EC 2.4.1.325     
Accepted name: TDP-N-acetylfucosamine:lipid II N-acetylfucosaminyltransferase
Reaction: dTDP-4-acetamido-4,6-dideoxy-α-D-galactose + N-acetyl-β-D-mannosaminouronyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol = dTDP + 4-acetamido-4,6-dideoxy-α-D-galactosyl-(1→4)-N-acetyl-β-D-mannosaminouronyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol
Glossary: dTDP-4-acetamido-4,6-dideoxy-α-D-galactose = dTDP-N-acetyl-α-D-fucosamine
a lipid II = an undecaprenyldiphospho-N-acetyl-(N-acetylglucosaminyl)muramoyl peptide; the peptide element refers to L-alanyl-D-γ-glutamyl-L-lysyl/meso-2,6-diaminopimelyl-D-alanyl-D-alanine or a modified version thereof = an undecaprenyldiphospho-4-O-(N-acetyl-β-D-glucosaminyl)-3-O-peptidyl-α-N-acetylmuramate; the peptide element refers to L-alanyl-D-γ-glutamyl-L-lysyl/meso-2,6-diaminopimelyl-D-alanyl-D-alanine or a modified version thereof
lipid III = N-acetyl-β-D-fucosyl-(1→4)-N-acetyl-β-D-mannosaminouronyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol
Other name(s): TDP-Fuc4NAc:lipid II Fuc4NAc-transferase; TDP-Fuc4NAc:lipid II Fuc4NAc transferase; wecF (gene name)
Systematic name: dTDP-N-acetyl-α-D-fucose:N-acetyl-β-D-mannosaminouronyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol N-acetylfucosaminyltransferase
Comments: Involved in the enterobacterial common antigen (ECA) biosynthesis in the bacterium Escherichia coli. The trisaccharide of the product (lipid III) is the repeat unit of ECA.
References:
1.  Rahman, A., Barr, K. and Rick, P.D. Identification of the structural gene for the TDP-Fuc4NAc:lipid II Fuc4NAc transferase involved in synthesis of enterobacterial common antigen in Escherichia coli K-12. J. Bacteriol. 183 (2001) 6509–6516. [PMID: 11673418]
[EC 2.4.1.325 created 2014]
 
 
EC 2.4.1.343     
Accepted name: UDP-Gal:α-D-GlcNAc-diphosphoundecaprenol α-1,3-galactosyltransferase
Reaction: UDP-α-D-galactose + N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol = UDP + α-D-Gal-(1→3)-α-D-GlcNAc-diphospho-ditrans,octacis-undecaprenol
Other name(s): wclR (gene name)
Systematic name: UDP-α-D-galactose:N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol 3-α-galactosyltransferase (configuration-retaining)
Comments: The enzyme is involved in the the biosynthesis of the O-antigen repeating unit of Escherichia coli O3. Requires a divalent metal ion (Mn2+, Mg2+ or Fe2+). cf. EC 2.4.1.303, UDP-Gal:α-D-GlcNAc-diphosphoundecaprenol β-1,3-galactosyltransferase.
References:
1.  Chen, C., Liu, B., Xu, Y., Utkina, N., Zhou, D., Danilov, L., Torgov, V., Veselovsky, V. and Feng, L. Biochemical characterization of the novel α-1, 3-galactosyltransferase WclR from Escherichia coli O3. Carbohydr. Res. 430 (2016) 36–43. [PMID: 27196310]
[EC 2.4.1.343 created 2017]
 
 
EC 2.4.1.344     
Accepted name: type 2 galactoside α-(1,2)-fucosyltransferase
Reaction: GDP-β-L-fucose + β-D-galactosyl-(1→4)-N-acetyl-β-D-glucosaminyl-R = GDP + α-L-fucosyl-(1→2)-β-D-galactosyl-(1→4)-N-acetyl-β-D-glucosaminyl-R
Other name(s): blood group H α-2-fucosyltransferase (ambiguous); guanosine diphosphofucose-galactoside 2-L-fucosyltransferase (ambiguous); α-(1→2)-L-fucosyltransferase (ambiguous); α-2-fucosyltransferase (ambiguous); α-2-L-fucosyltransferase (ambiguous); blood-group substance H-dependent fucosyltransferase (ambiguous); guanosine diphosphofucose-glycoprotein 2-α-fucosyltransferase (ambiguous); guanosine diphosphofucose-lactose fucosyltransferase; GDP fucose-lactose fucosyltransferase; guanosine diphospho-L-fucose-lactose fucosyltransferase; guanosine diphosphofucose-β-D-galactosyl-α-2-L-fucosyltransferase (ambiguous); guanosine diphosphofucose-galactosylacetylglucosaminylgalactosylglucosylceramide α-L-fucosyltransferase (ambiguous); guanosine diphosphofucose-glycoprotein 2-α-L-fucosyltransferase (ambiguous); H-gene-encoded β-galactoside α(1→2)fucosyltransferase; β-galactoside α(1→2)fucosyltransferase (ambiguous); GDP-L-fucose:lactose fucosyltransferase; GDP-β-L-fucose:β-D-galactosyl-R 2-α-L-fucosyltransferase (ambiguous); FUT1 (gene name); FUT2 (gene name)
Systematic name: GDP-β-L-fucose:β-D-galactosyl-(1→4)-N-acetyl-β-D-glucosaminyl-R α-(1,2)-L-fucosyltransferase (configuration-inverting)
Comments: The enzyme acts on a glycoconjugates where R (see reaction) is a glycoprotein or glycosphingolipid. The recognized moiety of the substrate is known as a type 2 histo-blood group antigen precursor disaccharide, and the action of the enzyme produces an H type 2 antigen. Humans possess two enzymes able to catalyse this reaction, encoded by the FUT1 and FUT2 genes (also known as the H and Secretor genes, respectively), but only FUT1 is expressed in red blood cells. cf. EC 2.4.1.69, type 1 galactoside α-(1,2)-fucosyltransferase.
References:
1.  Basu, S., Basu, M. and Chien, J.L. Enzymatic synthesis of a blood group H-related glycosphingolipid by an α-fucosyltransferase from bovine spleen. J. Biol. Chem. 250 (1975) 2956–2962. [PMID: 804484]
2.  Grollman, A.P. GDP-L-fucose:lactose fucosyltransferase from mammary gland. Methods Enzymol. 8 (1966) 351–353.
3.  Ernst, L.K., Rajan, V.P., Larsen, R.D., Ruff, M.M. and Lowe, J.B. Stable expression of blood group H determinants and GDP-L-fucose: β-D-galactoside 2-α-L-fucosyltransferase in mouse cells after transfection with human DNA. J. Biol. Chem. 264 (1989) 3436–3447. [PMID: 2464598]
4.  Larsen, R.D., Ernst, L.K., Nair, R.P. and Lowe, J.B. Molecular cloning, sequence, and expression of a human GDP-L-fucose:β-D-galactoside 2-α-L-fucosyltransferase cDNA that can form the H blood group antigen. Proc. Natl. Acad. Sci. USA 87 (1990) 6674–6678. [PMID: 2118655]
[EC 2.4.1.344 created 2017]
 
 
EC 2.4.1.375     
Accepted name: rhamnogalacturonan I galactosyltransferase
Reaction: Transfer of a β-galactosyl residue in a β-(1→4) linkage from UDP-α-D-galactose to rhamnosyl residues within the rhamnogalacturonan I backbone.
Glossary: rhamnogalacturonan I backbone = [(1→2)-α-L-rhamnosyl-(1→4)-α-D-galacturonosyl]n
Systematic name: UDP-α-D-galactose:[rhamnogalacturonan I]-α-L-rhamnosyl β-1,4-galactosyltransferase (configuration-inverting)
Comments: The enzyme, characterized from the plant Vigna angularis (azuki beans), participates in the biosynthesis of rhamnogalacturonan I, one of the components of pectin in plant cell wall. It does not require any metal ions, and prefers substrates with a degree of polymerization larger than 9.
References:
1.  Matsumoto, N., Takenaka, Y., Wachananawat, B., Kajiura, H., Imai, T. and Ishimizu, T. Rhamnogalacturonan I galactosyltransferase: Detection of enzyme activity and its hyperactivation. Plant Physiol. Biochem. 142 (2019) 173–178. [PMID: 31299599]
[EC 2.4.1.375 created 2020]
 
 
EC 2.4.1.384     
Accepted name: NDP-glycosyltransferase
Reaction: an NDP-glycose + an acceptor = a glycosylated acceptor + NDP
Other name(s): yjiC (gene name)
Systematic name: NDP-glycose:acceptor glycosyltransferase
Comments: The enzyme, characterized from the bacterium Bacillus licheniformis DSM-13, is an extremely promiscuous glycosyltransferase. It can accept ADP-, GDP-, CDP-, TDP-, or UDP-activated glycose molecules as donors, and can glycosylate a large number of substrates, catalysing O-, N-, or S-glycosylation. While D-glucose is the primarily reported sugar being transferred, the enzyme has been shown to transfer D-galactose, 2-deoxy-D-glucose, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, L-fucose, L-rhamnose, D-glucuronate, and D-viosamine.
References:
1.  Pandey, R.P., Parajuli, P., Koirala, N., Park, J.W. and Sohng, J.K. Probing 3-hydroxyflavone for in vitro glycorandomization of flavonols by YjiC. Appl. Environ. Microbiol. 79 (2013) 6833–6838. [PMID: 23974133]
2.  Pandey, R.P., Gurung, R.B., Parajuli, P., Koirala, N., Tuoi le, T. and Sohng, J.K. Assessing acceptor substrate promiscuity of YjiC-mediated glycosylation toward flavonoids. Carbohydr. Res. 393 (2014) 26–31. [PMID: 24893262]
3.  Pandey, R.P., Parajuli, P., Shin, J.Y., Lee, J., Lee, S., Hong, Y.S., Park, Y.I., Kim, J.S. and Sohng, J.K. Enzymatic biosynthesis of novel resveratrol glucoside and glycoside derivatives. Appl. Environ. Microbiol. 80 (2014) 7235–7243. [PMID: 25239890]
4.  Parajuli, P., Pandey, R.P., Koirala, N., Yoon, Y.J., Kim, B.G. and Sohng, J.K. Enzymatic synthesis of epothilone A glycosides. AMB Express 4:31 (2014). [PMID: 24949266]
5.  Pandey, R.P., Parajuli, P., Gurung, R.B. and Sohng, J.K. Donor specificity of YjiC glycosyltransferase determines the conjugation of cytosolic NDP-sugar in in vivo glycosylation reactions. Enzyme Microb. Technol. 91 (2016) 26–33. [PMID: 27444326]
6.  Bashyal, P., Thapa, S.B., Kim, T.S., Pandey, R.P. and Sohng, J.K. Exploring the nucleophilic N- and S-glycosylation capacity of Bacillus licheniformis YjiC enzyme. J. Microbiol. Biotechnol. 30 (2020) 1092–1096. [PMID: 32238768]
[EC 2.4.1.384 created 2021]
 
 
EC 2.4.1.388     
Accepted name: glucosylgalactose phosphorylase
Reaction: β-D-glucosyl-(1→4)-D-galactose + phosphate = α-D-glucopyranose 1-phosphate + D-galactopyranose
Other name(s): 4-O-β-D-glucosyl-D-galactose phosphorylase
Systematic name: β-D-glucosyl-(1→4)-D-galactose:phosphate α-D-glucosyltransferase (configuration-inverting)
Comments: The enzyme from the bacterium Paenibacillus polymyxa belongs to glycoside hydrolase family 94. It has a much lower activity with 4-O-β-D-glucosyl-L-arabinose.
References:
1.  De Doncker, M., De Graeve, C., Franceus, J., Beerens, K., Kren, V., Pelantova, H., Vercauteren, R. and Desmet, T. Exploration of GH94 sequence space for enzyme discovery reveals a novel glucosylgalactose phosphorylase specificity. ChemBioChem (2021) . [PMID: 34541742]
[EC 2.4.1.388 created 2022]
 
 
EC 2.4.1.389     
Accepted name: solabiose phosphorylase
Reaction: solabiose + phosphate = D-galactose + α-D-glucose 1-phosphate
Glossary: solabiose = β-D-glucopyranosyl-(1→3)-D-galactose
Systematic name: solabiose:phosphate α-D-glucosyltransferase
Comments: The enzyme, characterized from the bacterium Paenibacillus borealis, belongs to glycoside hydrolase family 94 (GH94).
References:
1.  Saburi, W., Nihira, T., Nakai, H., Kitaoka, M. and Mori, H. Discovery of solabiose phosphorylase and its application for enzymatic synthesis of solabiose from sucrose and lactose. Sci. Rep. 12:259 (2022). [PMID: 34997180]
[EC 2.4.1.389 created 2022]
 
 
EC 2.4.2.41     
Accepted name: xylogalacturonan β-1,3-xylosyltransferase
Reaction: Transfers a xylosyl residue from UDP-D-xylose to a D-galactose residue in xylogalacturonan, forming a β-1,3-D-xylosyl-D-galactose linkage.
Other name(s): xylogalacturonan xylosyltransferase; XGA xylosyltransferase
Systematic name: UDP-D-xylose:xylogalacturonan 3-β-D-xylosyltransferase
Comments: Involved in plant cell wall synthesis. The enzyme from Arabidopsis thaliana also transfers D-xylose from UDP-D-xylose onto oligogalacturonide acceptors. The enzyme did not show significant activity with UDP-glucose, UDP-galactose, or UDP-N-acetyl-D-glucosamine as sugar donors.
References:
1.  Jensen, J.K., Sorensen, S.O., Harholt, J., Geshi, N., Sakuragi, Y., Moller, I., Zandleven, J., Bernal, A.J., Jensen, N.B., Sorensen, C., Pauly, M., Beldman, G., Willats, W.G. and Scheller, H.V. Identification of a xylogalacturonan xylosyltransferase involved in pectin biosynthesis in Arabidopsis. Plant Cell 20 (2008) 1289–1302. [PMID: 18460606]
[EC 2.4.2.41 created 2009]
 
 
EC 2.4.3.4     
Accepted name: β-galactoside α-2,3-sialyltransferase
Reaction: CMP-N-acetylneuraminate + β-D-galactosyl-(1→3)-N-acetyl-α-D-galactosaminyl-R = CMP + α-N-acetylneuraminyl-(2→3)-β-D-galactosyl-(1→3)-N-acetyl-α-D-galactosaminyl-R
Other name(s): CMP-N-acetylneuraminate:β-D-galactoside α-2,3-N-acetylneuraminyl-transferase
Systematic name: CMP-N-acetylneuraminate:β-D-galactoside α-(2→3)-N-acetylneuraminyl-transferase
Comments: The acceptor is Galβ1,3GalNAc-R, where R is H, a threonine or serine residue in a glycoprotein, or a glycolipid. Lactose can also act as acceptor. May be identical with EC 2.4.3.2 β-D-galactosyl-(1→3)-N-acetyl-β-D-galactosaminide α-2,3-sialyltransferase.
References:
1.  Rearick, J.I., Sadler, J.E., Paulson, J.C. and Hill, R.L. Enzymatic characterization of β D-galactoside α2→3 sialyltransferase from porcine submaxillary gland. J. Biol. Chem. 254 (1979) 4444–4451. [PMID: 438198]
2.  Sadler, J.E., Rearick, J.I., Paulson, J.C. and Hill, R.L. Purification to homogeneity of a β-galactoside α2→3 sialyltransferase and partial purification of an α-N-acetylgalactosaminide α2→6 sialyltransferase from porcine submaxillary glands. J. Biol. Chem. 254 (1979) 4434–4442. [PMID: 438196]
[EC 2.4.3.4 created 1984 as EC 2.4.99.4, modified 1986, transferred 2022 to EC 2.4.3.4]
 
 
EC 2.4.3.9     
Accepted name: lactosylceramide α-2,3-sialyltransferase
Reaction: CMP-N-acetylneuraminate + β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide = CMP + α-N-acetylneuraminyl-(2→3)-β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide
Glossary: lactosylceramide = β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide
Other name(s): cytidine monophosphoacetylneuraminate-lactosylceramide α2,3- sialyltransferase; CMP-acetylneuraminate-lactosylceramide-sialyltransferase; CMP-acetylneuraminic acid:lactosylceramide sialyltransferase; CMP-sialic acid:lactosylceramide-sialyltransferase; cytidine monophosphoacetylneuraminate-lactosylceramide sialyltransferase; ganglioside GM3 synthetase; GM3 synthase; GM3 synthetase; SAT 1; CMP-N-acetylneuraminate:lactosylceramide α-2,3-N-acetylneuraminyltransferase; CMP-N-acetylneuraminate:β-D-galactosyl-(1→4)-β-D-glucosyl(1↔1)ceramide α-(2→3)-N-acetylneuraminyltransferase
Systematic name: CMP-N-acetylneuraminate:β-D-galactosyl-(1→4)-β-D-glucosyl-(1↔1)-ceramide α-(2→3)-N-acetylneuraminyltransferase
Comments: Lactose cannot act as acceptor.
References:
1.  Basu, S., Kaufman, B. and Roseman, S. Enzymatic synthesis of glucocerebroside by a glucosyltransferase from embryonic chicken brain. J. Biol. Chem. 248 (1973) 1388–1394. [PMID: 4631392]
2.  Fishman, P.H., Bradley, R.M. and Henneberry, R.C. Butyrate-induced glycolipid biosynthesis in HeLa cells: properties of the induced sialyltransferase. Arch. Biochem. Biophys. 172 (1976) 618–626. [PMID: 4022]
3.  Higashi, H., Basu, M. and Basu, S. Biosynthesis in vitro of disialosylneolactotetraosylceramide by a solubilized sialyltransferase from embryonic chicken brain. J. Biol. Chem. 260 (1985) 824–828. [PMID: 3838172]
[EC 2.4.3.9 created 1984 as EC 2.4.99.9, modified 1986, transferred 2022 to EC 2.4.3.9]
 
 
EC 2.4.99.4      
Transferred entry: β-galactoside α-2,3-sialyltransferase. Now EC 2.4.3.4, β-galactoside α-2,3-sialyltransferase
[EC 2.4.99.4 created 1984, modified 1986, deleted 2022]
 
 
EC 2.4.99.9      
Transferred entry: lactosylceramide α-2,3-sialyltransferase. Now EC 2.4.3.9, lactosylceramide α-2,3-sialyltransferase
[EC 2.4.99.9 created 1984, modified 1986, deleted 2022]
 
 
EC 2.5.1.5     
Accepted name: galactose-6-sulfurylase
Reaction: Eliminates sulfate from the D-galactose 6-sulfate residues of porphyran, producing 3,6-anhydrogalactose residues
Glossary: porphyran = is a linear polysaccharide produced by the red algae Porphyra. Its backbone is composed of about 30% agarose repeating units (alternating D-galactose and 3,6-anhydro-α-L-galactopyranose residues joined by α-(1→3)- and β-(1→4)-linkages), with the remaining residues being 3-linked β-D-galactopyranose and 4-linked α-L-galactopyranose-6-sulfate.
Other name(s): porphyran sulfatase; galactose-6-sulfatase; galactose 6-sulfatase
Systematic name: D-galactose-6-sulfate:alkyltransferase (cyclizing)
References:
1.  Rees, D.A. Enzymic desulphation of porphyran. Biochem. J. 80 (1961) 449–453. [PMID: 13740282]
2.  Rees, D.A. Enzymic synthesis of 3:6-anhydro-L-galactose within porphyran from L-galactose 6-sulphate units. Biochem. J. 81 (1961) 347–352. [PMID: 16748934]
[EC 2.5.1.5 created 1965]
 
 
EC 2.6.1.59     
Accepted name: dTDP-4-amino-4,6-dideoxygalactose transaminase
Reaction: dTDP-4-amino-4,6-dideoxy-α-D-galactose + 2-oxoglutarate = dTDP-4-dehydro-6-deoxy-α-D-galactose + L-glutamate
Glossary: dTDP-4-dehydro-6-deoxy-α-D-galactose = dTDP-4-dehydro-6-deoxy-α-D-glucose
Other name(s): thymidine diphosphoaminodideoxygalactose aminotransferase; thymidine diphosphate 4-keto-6-deoxy-D-glucose transaminase; WecE; dTDP-4,6-dideoxy-D-galactose:2-oxoglutarate aminotransferase; dTDP-4,6-dideoxy-α-D-galactose:2-oxoglutarate aminotransferase
Systematic name: dTDP-4-amino-4,6-dideoxy-α-D-galactose:2-oxoglutarate aminotransferase
Comments: A pyridoxal-phosphate protein.
References:
1.  Ohashi, H., Matsuhashi, M. and Matsuhashi, S. Thymidine diphosphate 4-acetamido-4,6-dideoxyhexoses. IV. Purification and properties of thymidine diphosphate 4-keto-6-deoxy-D-glucose transaminase from Pasteurella pseudotuberculosis. J. Biol. Chem. 246 (1971) 2325–2330. [PMID: 4928644]
2.  Hwang, B.Y., Lee, H.J., Yang, Y.H., Joo, H.S. and Kim, B.G. Characterization and investigation of substrate specificity of the sugar aminotransferase WecE from E. coli K12. Chem. Biol. 11 (2004) 915–925. [PMID: 15271350]
[EC 2.6.1.59 created 1978]
 
 
EC 2.6.1.90     
Accepted name: dTDP-3-amino-3,6-dideoxy-α-D-galactopyranose transaminase
Reaction: dTDP-3-amino-3,6-dideoxy-α-D-galactopyranose + 2-oxoglutarate = dTDP-3-dehydro-6-deoxy-α-D-galactopyranose + L-glutamate
Glossary: dTDP-3-dehydro-6-deoxy-D-galactopyranose = dTDP-6-deoxy-D-xylo-hexopyranos-3-ulose
Other name(s): dTDP-6-deoxy-D-xylohex-3-uloseaminase; FdtB; TDP-3-keto-6-deoxy-D-galactose-3-aminotransferase; RavAMT; TDP-3-keto-6-deoxy-D-galactose 3-aminotransferase; TDP-3-dehydro-6-deoxy-D-galactose 3-aminotransferase
Systematic name: dTDP-3-amino-3,6-dideoxy-α-D-galactopyranose:2-oxoglutarate aminotransferase
Comments: A pyridoxal-phosphate protein. The enzyme is involved in the biosynthesis of dTDP-3-acetamido-3,6-dideoxy-α-D-galactose. The reaction occurs in the reverse direction.
References:
1.  Pfoestl, A., Hofinger, A., Kosma, P. and Messner, P. Biosynthesis of dTDP-3-acetamido-3,6-dideoxy-α-D-galactose in Aneurinibacillus thermoaerophilus L420-91T. J. Biol. Chem. 278 (2003) 26410–26417. [PMID: 12740380]
[EC 2.6.1.90 created 2011]
 
 
EC 2.7.1.6     
Accepted name: galactokinase
Reaction: ATP + α-D-galactose = ADP + α-D-galactose 1-phosphate
Other name(s): galactokinase (phosphorylating); ATP:D-galactose-1-phosphotransferase
Systematic name: ATP:α-D-galactose 1-phosphotransferase
Comments: Part of the Leloir pathway for galactose metabolism. The enzymes from mammals and from the bacterium Escherichia coli have no activity with N-acetyl-α-D-galactosamine [4-6].
References:
1.  Cardini, C.E. and Leloir, L.F. Enzymic phosphorylation of galactosamine and galactose. Arch. Biochem. Biophys. 45 (1953) 55–64. [PMID: 13058412]
2.  Neufeld, E.F., Feingold, D.S. and Hassid, W.Z. Phosphorylation of D-galactose and L-arabinose by extracts from Phaseolus aureus seedlings. J. Biol. Chem. 235 (1960) 906–909. [PMID: 14426659]
3.  Wilkinson, J.F. The pathway of the adaptive fermentation of galactose by yeast. Biochem. J. 44 (1949) 460–467. [PMID: 16748546]
4.  Yang, J., Fu, X., Jia, Q., Shen, J., Biggins, J.B., Jiang, J., Zhao, J., Schmidt, J.J., Wang, P.G. and Thorson, J.S. Studies on the substrate specificity of Escherichia coli galactokinase. Org. Lett. 5 (2003) 2223–2226. [PMID: 12816414]
5.  Timson, D.J. and Reece, R.J. Sugar recognition by human galactokinase. BMC Biochem. 4:16 (2003). [PMID: 14596685]
6.  Thoden, J.B., Timson, D.J., Reece, R.J. and Holden, H.M. Molecular structure of human galactokinase: implications for type II galactosemia. J. Biol. Chem. 280 (2005) 9662–9670. [PMID: 15590630]
[EC 2.7.1.6 created 1961]
 
 
EC 2.7.1.46     
Accepted name: L-arabinokinase
Reaction: ATP + L-arabinose = ADP + β-L-arabinose 1-phosphate
Other name(s): L-arabinokinase (phosphorylating)
Systematic name: ATP:L-arabinose 1-phosphotransferase
References:
1.  Neufeld, E.F., Feingold, D.S. and Hassid, W.Z. Phosphorylation of D-galactose and L-arabinose by extracts from Phaseolus aureus seedlings. J. Biol. Chem. 235 (1960) 906–909. [PMID: 14426659]
[EC 2.7.1.46 created 1965]
 
 
EC 2.7.1.52     
Accepted name: fucokinase
Reaction: ATP + L-fucose = ADP + β-L-fucose 1-phosphate
Other name(s): fucokinase (phosphorylating); fucose kinase; L-fucose kinase; L-fucokinase; ATP:6-deoxy-L-galactose 1-phosphotransferase; ATP:L-fucose 1-phosphotransferase
Systematic name: ATP:β-L-fucose 1-phosphotransferase
Comments: Requires a divalent cation for activity, with Mg2+ and Fe2+ giving rise to the highest enzyme activity. Forms part of a salvage pathway for reutilization of L-fucose. Can also phosphorylate D-arabinose, but more slowly.
References:
1.  Ishihara, H., Massaro, D.J. and Heath, E.C. The metabolism of L-fucose. 3. The enzymatic synthesis of β-L-fucose 1-phosphate. J. Biol. Chem. 243 (1968) 1103–1109. [PMID: 5646161]
2.  Butler, W. and Serif, G.S. Fucokinase, its anomeric specificity and mechanism of phosphate group transfer. Biochim. Biophys. Acta 829 (1985) 238–243. [PMID: 2986701]
3.  Park, S.H., Pastuszak, I., Drake, R. and Elbein, A.D. Purification to apparent homogeneity and properties of pig kidney L-fucose kinase. J. Biol. Chem. 273 (1998) 5685–5691. [PMID: 9488699]
[EC 2.7.1.52 created 1972, modified 2004]
 
 
EC 2.7.1.58     
Accepted name: 2-dehydro-3-deoxygalactonokinase
Reaction: ATP + 2-dehydro-3-deoxy-D-galactonate = ADP + 2-dehydro-3-deoxy-6-phospho-D-galactonate
Other name(s): 2-keto-3-deoxygalactonokinase; 2-keto-3-deoxygalactonate kinase (phosphorylating); 2-oxo-3-deoxygalactonate kinase
Systematic name: ATP:2-dehydro-3-deoxy-D-galactonate 6-phosphotransferase
References:
1.  Stouthamer, A.H. Glucose and galactose metabolism in Gluconobacter liquefaciens. Biochim. Biophys. Acta 48 (1961) 484–500.
[EC 2.7.1.58 created 1972]
 
 
EC 2.7.1.69      
Transferred entry: protein-Nπ-phosphohistidine—sugar phosphotransferase, now covered by EC 2.7.1.191 protein-Nπ-phosphohistidine—D-mannose phosphotransferase, EC 2.7.1.192 protein-Nπ-phosphohistidine—N-acetylmuramate phosphotransferase, EC 2.7.1.193 protein-Nπ-phosphohistidine—N-acetyl-D-glucosamine phosphotransferase, EC 2.7.1.194 protein-Nπ-phosphohistidine—L-ascorbate phosphotransferase, EC 2.7.1.195 protein-Nπ-phosphohistidine—2-O-α-mannosyl-D-glycerate phosphotransferase, EC 2.7.1.196 protein-Nπ-phosphohistidine—N,N′-diacetylchitobiose phosphotransferase, EC 2.7.1.197 protein-Nπ-phosphohistidine—D-mannitol phosphotransferase, EC 2.7.1.198 protein-Nπ-phosphohistidine—D-sorbitol phosphotransferase, EC 2.7.1.199 protein-Nπ-phosphohistidine—D-glucose phosphotransferase, EC 2.7.1.200 protein-Nπ-phosphohistidine—galactitol phosphotransferase, EC 2.7.1.201 protein-Nπ-phosphohistidine—trehalose phosphotransferase, EC 2.7.1.202 protein-Nπ-phosphohistidine—D-fructose phosphotransferase, EC 2.7.1.203 protein-Nπ-phosphohistidine—D-glucosaminate phosphotransferase, EC 2.7.1.204 protein-Nπ-phosphohistidine—D-galactose phosphotransferase, EC 2.7.1.205 protein-Nπ-phosphohistidine—D-cellobiose phosphotransferase, EC 2.7.1.206 protein-Nπ-phosphohistidine—L-sorbose phosphotransferase, EC 2.7.1.207 protein-Nπ-phosphohistidine—lactose phosphotransferase and EC 2.7.1.208 protein-Nπ-phosphohistidine—maltose phosphotransferase.
[EC 2.7.1.69 created 1972, modified 2000, deleted 2016]
 
 
EC 2.7.1.157     
Accepted name: N-acetylgalactosamine kinase
Reaction: ATP + N-acetyl-α-D-galactosamine = ADP + N-acetyl-α-D-galactosamine 1-phosphate
Other name(s): GALK2; GK2; GalNAc kinase; N-acetylgalactosamine (GalNAc)-1-phosphate kinase; ATP:N-acetyl-D-galactosamine 1-phosphotransferase
Systematic name: ATP:N-acetyl-α-D-galactosamine 1-phosphotransferase
Comments: The enzyme is highly specific for GalNAc as substrate, but has slight activity with D-galactose [2]. Requires Mg2+, Mn2+ or Co2+ for activity, with Mg2+ resulting in by far the greatest stimulation of enzyme activity.
References:
1.  Pastuszak, I., Drake, R. and Elbein, A.D. Kidney N-acetylgalactosamine (GalNAc)-1-phosphate kinase, a new pathway of GalNAc activation. J. Biol. Chem. 271 (1999) 20776–20782. [PMID: 8702831]
2.  Pastuszak, I., O'Donnell, J. and Elbein, A.D. Identification of the GalNAc kinase amino acid sequence. J. Biol. Chem. 271 (1996) 23653–23656. [PMID: 8798585]
3.  Thoden, J.B. and Holden, H.M. The molecular architecture of human N-acetylgalactosamine kinase. J. Biol. Chem. 280 (2005) 32784–32791. [PMID: 16006554]
[EC 2.7.1.157 created 2005]
 
 
EC 2.7.1.178     
Accepted name: 2-dehydro-3-deoxyglucono/galactono-kinase
Reaction: (1) ATP + 2-dehydro-3-deoxy-D-gluconate = ADP + 2-dehydro-3-deoxy-6-phospho-D-gluconate
(2) ATP + 2-dehydro-3-deoxy-D-galactonate = ADP + 2-dehydro-3-deoxy-6-phospho-D-galactonate
Other name(s): KDG kinase (ambiguous); KDGK (ambiguous); 2-keto-3-deoxy-D-gluconate kinase (ambiguous)
Systematic name: ATP:2-dehydro-3-deoxy-D-gluconate/2-dehydro-3-deoxy-D-galactonate 6-phosphotransferase
Comments: The enzyme from the archaeon Sulfolobus solfataricus is involved in glucose and galactose catabolism via the branched variant of the Entner-Doudoroff pathway. It phosphorylates 2-dehydro-3-deoxy-D-gluconate and 2-dehydro-3-deoxy-D-galactonate with similar catalytic efficiency. cf. EC 2.7.1.45, 2-dehydro-3-deoxygluconokinase and EC 2.7.1.58, 2-dehydro-3-deoxygalactonokinase.
References:
1.  Lamble, H.J., Theodossis, A., Milburn, C.C., Taylor, G.L., Bull, S.D., Hough, D.W. and Danson, M.J. Promiscuity in the part-phosphorylative Entner-Doudoroff pathway of the archaeon Sulfolobus solfataricus. FEBS Lett. 579 (2005) 6865–6869. [PMID: 16330030]
2.  Potter, J.A., Kerou, M., Lamble, H.J., Bull, S.D., Hough, D.W., Danson, M.J. and Taylor, G.L. The structure of Sulfolobus solfataricus 2-keto-3-deoxygluconate kinase. Acta Crystallogr. D Biol. Crystallogr. 64 (2008) 1283–1287. [PMID: 19018105]
3.  Kim, S. and Lee, S.B. Characterization of Sulfolobus solfataricus 2-keto-3-deoxy-D-gluconate kinase in the modified Entner-Doudoroff pathway. Biosci. Biotechnol. Biochem. 70 (2006) 1308–1316. [PMID: 16794308]
[EC 2.7.1.178 created 2013]
 
 
EC 2.7.1.196     
Accepted name: protein-Nπ-phosphohistidine—N,N′-diacetylchitobiose phosphotransferase
Reaction: [protein]-Nπ-phospho-L-histidine + N,N′-diacetylchitobiose[side 1] = [protein]-L-histidine + N,N′-diacetylchitobiose 6′-phosphate[side 2]
Other name(s): chbABC (gene names); N,N′-diacetylchitobiose PTS permease; chitobiose PTS permease; EIIcel; EIIchb; Enzyme IIcel; Enzyme IIchb
Systematic name: protein-Nπ-phospho-L-histidine:N,N′-diacetylchitobiose Nπ-phosphotransferase
Comments: This enzyme is a component (known as enzyme II) of a phosphoenolpyruvate (PEP)-dependent, sugar transporting phosphotransferase system (PTS). The system, which is found only in prokaryotes, simultaneously transports its substrate from the periplasm or extracellular space into the cytoplasm and phosphorylates it. The phosphate donor, which is shared among the different systems, is a phospho-carrier protein of low molecular mass that has been phosphorylated by EC 2.7.3.9 (phosphoenolpyruvate—protein phosphotransferase). Enzyme II, on the other hand, is specific for a particular substrate, although in some cases alternative substrates can be transported with lower efficiency. The reaction involves a successive transfer of the phosphate group to several amino acids within the enzyme before the final transfer to the substrate.
References:
1.  Keyhani, N.O., Wang, L.X., Lee, Y.C. and Roseman, S. The chitin disaccharide, N,N′-diacetylchitobiose, is catabolized by Escherichia coli and is transported/phosphorylated by the phosphoenolpyruvate:glycose phosphotransferase system. J. Biol. Chem. 275 (2000) 33084–33090. [PMID: 10913117]
2.  Reizer, J., Reizer, A. and Saier, M.H., Jr. The cellobiose permease of Escherichia coli consists of three proteins and is homologous to the lactose permease of Staphylococcus aureus. Res. Microbiol. 141 (1990) 1061–1067. [PMID: 2092358]
3.  Keyhani, N.O., Boudker, O. and Roseman, S. Isolation and characterization of IIAChb, a soluble protein of the enzyme II complex required for the transport/phosphorylation of N, N′-diacetylchitobiose in Escherichia coli. J. Biol. Chem. 275 (2000) 33091–33101. [PMID: 10913118]
4.  Keyhani, N.O., Bacia, K. and Roseman, S. The transport/phosphorylation of N,N′-diacetylchitobiose in Escherichia coli. Characterization of phospho-IIB(Chb) and of a potential transition state analogue in the phosphotransfer reaction between the proteins IIA(Chb) AND IIB(Chb). J. Biol. Chem. 275 (2000) 33102–33109. [PMID: 10913119]
[EC 2.7.1.196 created 1972 as EC 2.7.1.69, part transferred 2016 to EC 2.7.1.196]
 
 
EC 2.7.1.204     
Accepted name: protein-Nπ-phosphohistidine—D-galactose phosphotransferase
Reaction: [protein]-Nπ-phospho-L-histidine + D-galactose[side 1] = [protein]-L-histidine + D-galactose 6-phosphate[side 2]
Other name(s): D-galactose PTS permease; EIIGal; Enzyme IIGal
Systematic name: protein-Nπ-phospho-L-histidine:D-galactose Nπ-phosphotransferase
Comments: This enzyme is a component (known as enzyme II) of a phosphoenolpyruvate (PEP)-dependent, sugar transporting phosphotransferase system (PTS). The system, which is found only in prokaryotes, simultaneously transports its substrate from the periplasm or extracellular space into the cytoplasm and phosphorylates it. The phosphate donor, which is shared among the different systems, is a phospho-carrier protein of low molecular mass that has been phosphorylated by EC 2.7.3.9 (phosphoenolpyruvate—protein phosphotransferase). Enzyme II, on the other hand, is specific for a particular substrate, although in some cases alternative substrates can be transported with lower efficiency. The reaction involves a successive transfer of the phosphate group to several amino acids within the enzyme before the final transfer to the substrate.
References:
1.  Zeng, L., Martino, N.C. and Burne, R.A. Two gene clusters coordinate galactose and lactose metabolism in Streptococcus gordonii. Appl. Environ. Microbiol. 78 (2012) 5597–5605. [PMID: 22660715]
2.  Zeng, L., Xue, P., Stanhope, M.J. and Burne, R.A. A galactose-specific sugar: phosphotransferase permease is prevalent in the non-core genome of Streptococcus mutans. Mol Oral Microbiol 28 (2013) 292–301. [PMID: 23421335]
[EC 2.7.1.204 created 1972 as EC 2.7.1.69, part transferred 2016 to EC 2.7.1.204]
 
 
EC 2.7.1.207     
Accepted name: protein-Nπ-phosphohistidine—lactose phosphotransferase
Reaction: [protein]-Nπ-phospho-L-histidine + lactose[side 1] = [protein]-L-histidine + lactose 6′-phosphate[side 2]
Other name(s): lacEF (gene names); lactose PTS permease; EIILac; Enzyme IILac
Systematic name: protein-Nπ-phospho-L-histidine:lactose Nπ-phosphotransferase
Comments: This enzyme is a component (known as enzyme II) of a phosphoenolpyruvate (PEP)-dependent, sugar transporting phosphotransferase system (PTS). The system, which is found only in prokaryotes, simultaneously transports its substrate from the periplasm or extracellular space into the cytoplasm and phosphorylates it. The phosphate donor, which is shared among the different systems, is a phospho-carrier protein of low molecular mass that has been phosphorylated by EC 2.7.3.9 (phosphoenolpyruvate—protein phosphotransferase). Enzyme II, on the other hand, is specific for a particular substrate, although in some cases alternative substrates can be transported with lower efficiency. The reaction involves a successive transfer of the phosphate group to several amino acids within the enzyme before the final transfer to the substrate.
References:
1.  Hengstenberg, W. Solubilization of the membrane bound lactose specific component of the staphylococcal PEP dependant phosphotransferase system. FEBS Lett. 8 (1970) 277–280. [PMID: 11947593]
2.  Vadeboncoeur, C. and Proulx, M. Lactose transport in Streptococcus mutans: isolation and characterization of factor IIIlac, a specific protein component of the phosphoenolpyruvate-lactose phosphotransferase system. Infect. Immun. 46 (1984) 213–219. [PMID: 6480107]
3.  Breidt, F., Jr., Hengstenberg, W., Finkeldei, U. and Stewart, G.C. Identification of the genes for the lactose-specific components of the phosphotransferase system in the lac operon of Staphylococcus aureus. J. Biol. Chem. 262 (1987) 16444–16449. [PMID: 2824493]
4.  De Vos, W.M., Boerrigter, I., Van Rooijen, R.J., Reiche, B., Hengstenberg, W. Characterization of the lactose-specific enzymes of the phosphotransferase system in Lactococcus lactis. J. Biol. Chem. 265 (1990) 22554–22560. [PMID: 2125052]
5.  Peters, D., Frank, R. and Hengstenberg, W. Lactose-specific enzyme II of the phosphoenolpyruvate-dependent phosphotransferase system of Staphylococcus aureus. Purification of the histidine-tagged transmembrane component IICBLac and its hydrophilic IIB domain by metal-affinity chromatography, and functional characterization. Eur. J. Biochem. 228 (1995) 798–804. [PMID: 7737179]
[EC 2.7.1.207 created 1972 as EC 2.7.1.69, part transferred 2016 to EC 2.7.1.207]
 
 
EC 2.7.7.9     
Accepted name: UTP—glucose-1-phosphate uridylyltransferase
Reaction: UTP + α-D-glucose 1-phosphate = diphosphate + UDP-glucose
Other name(s): UDP glucose pyrophosphorylase; glucose-1-phosphate uridylyltransferase; UDPG phosphorylase; UDPG pyrophosphorylase; uridine 5′-diphosphoglucose pyrophosphorylase; uridine diphosphoglucose pyrophosphorylase; uridine diphosphate-D-glucose pyrophosphorylase; uridine-diphosphate glucose pyrophosphorylase
Systematic name: UTP:α-D-glucose-1-phosphate uridylyltransferase
References:
1.  Kalckar, H.M. The role of phosphoglycosyl compounds in the biosynthesis of nucleosides and nucleotides. Biochim. Biophys. Acta 12 (1953) 250–264. [PMID: 13115434]
2.  Kamogawa, A. and Kurahashi, K. Purification and properties of uridinediphosphate glucose pyrophosphorylase from Escherichia coli K12. J. Biochem. (Tokyo) 57 (1965) 758–765. [PMID: 4284510]
3.  Lobelle-Rich, P.A. and Reeves, R.E. Separation and characterization of two UTP-utilizing hexose phosphate uridylyltransferases from Entamoeba histolytica. Mol. Biochem. Parasitol. 7 (1983) 173–182. [PMID: 6304512]
4.  Smith, E.E.B. and Mills, G.T. The uridyl transferase of mammary gland. Biochim. Biophys. Acta 18 (1955) 152. [PMID: 13260264]
5.  Turnquist, R.L., Gillett, T.A. and Hansen, R.G. Uridine diphosphate glucose pyrophosphorylase. Crystallization and properties of the enzyme from rabbit liver and species comparisons. J. Biol. Chem. 249 (1974) 7695–7700. [PMID: 4436332]
[EC 2.7.7.9 created 1961]
 
 
EC 2.7.7.10     
Accepted name: UTP—hexose-1-phosphate uridylyltransferase
Reaction: UTP + α-D-galactose 1-phosphate = diphosphate + UDP-α-D-galactose
Other name(s): galactose-1-phosphate uridylyltransferase; galactose 1-phosphate uridylyltransferase; α-D-galactose 1-phosphate uridylyltransferase; galactose 1-phosphate uridyltransferase; UDPgalactose pyrophosphorylase; uridine diphosphate galactose pyrophosphorylase; uridine diphosphogalactose pyrophosphorylase
Systematic name: UTP:α-D-hexose-1-phosphate uridylyltransferase
Comments: α-D-Glucose 1-phosphate can also act as acceptor, but more slowly.
References:
1.  Isselbacher, K.J. A mammalian uridinediphosphate galactose pyrophosphorylase. J. Biol. Chem. 232 (1958) 429–444. [PMID: 13549431]
2.  Kalckar, H.M. The role of phosphoglycosyl compounds in the biosynthesis of nucleosides and nucleotides. Biochim. Biophys. Acta 12 (1953) 250–264. [PMID: 13115434]
3.  Lee, L., Kimura, A. and Tochikura, T. Purification and properties of UDP-glucose (UDP-galactose) pyrophosphorylase from Bifidobacterium bifidum. J. Biochem. (Tokyo) 86 (1979) 923–928. [PMID: 500588]
4.  Lobelle-Rich, P.A. and Reeves, R.E. Separation and characterization of two UTP-utilizing hexose phosphate uridylyltransferases from Entamoeba histolytica. Mol. Biochem. Parasitol. 7 (1983) 173–182. [PMID: 6304512]
[EC 2.7.7.10 created 1961]
 
 
EC 2.7.7.12     
Accepted name: UDP-glucose—hexose-1-phosphate uridylyltransferase
Reaction: UDP-α-D-glucose + α-D-galactose 1-phosphate = α-D-glucose 1-phosphate + UDP-α-D-galactose
Other name(s): uridyl transferase; hexose-1-phosphate uridylyltransferase; uridyltransferase; hexose 1-phosphate uridyltransferase; UDP-glucose:α-D-galactose-1-phosphate uridylyltransferase
Systematic name: UDP-α-D-glucose:α-D-galactose-1-phosphate uridylyltransferase
References:
1.  Kalckar, H.M., Braganca, B. and Munch-Petersen, A. Uridyl transferases and the formation of uridinediphosphogalactose. Nature 172 (1953) 1038. [PMID: 13111247]
2.  Kurahashi, K. and Sugimura, A. Purification and properties of galactose 1-phosphate uridyl transferase from Escherichia coli. J. Biol. Chem. 235 (1960) 940–946. [PMID: 14412847]
3.  Mayes, J.S. and Hansen, R.G. Galactose 1-phosphate uridyl transferase. Methods Enzymol. 9 (1966) 708–713.
4.  Saito, S., Ozutsumi, M. and Kurahashi, K. Galactose 1-phosphate uridylyltransferase of Escherichia coli. II. Further purification and characterization. J. Biol. Chem. 242 (1967) 2362–2368. [PMID: 5338129]
5.  Smith, E.E.B. and Mills, G.T. The uridyl transferase of mammary gland. Biochim. Biophys. Acta 18 (1955) 152. [PMID: 13260264]
[EC 2.7.7.12 created 1961]
 
 
EC 2.7.7.32     
Accepted name: galactose-1-phosphate thymidylyltransferase
Reaction: dTTP + α-D-galactose 1-phosphate = diphosphate + dTDP-galactose
Other name(s): dTDP galactose pyrophosphorylase; galactose 1-phosphate thymidylyl transferase; thymidine diphosphogalactose pyrophosphorylase; thymidine triphosphate:α-D-galactose 1-phosphate thymidylyltransferase
Systematic name: dTTP:α-D-galactose-1-phosphate thymidylyltransferase
References:
1.  Pazur, J.H. and Anderson, J.S. Thymidine triphosphate: α-D-galactose 1-phosphate thymidylyltransferase from Streptococcus faecalis grown on D-galactose. J. Biol. Chem. 238 (1963) 3155–3160. [PMID: 14085355]
[EC 2.7.7.32 created 1972]
 
 
EC 2.7.7.69     
Accepted name: GDP-L-galactose/GDP-D-glucose: hexose 1-phosphate guanylyltransferase
Reaction: (1) GDP-β-L-galactose + α-D-mannose 1-phosphate = β-L-galactose 1-phosphate + GDP-α-D-mannose
(2) GDP-α-D-glucose + α-D-mannose 1-phosphate = α-D-glucose 1-phosphate + GDP-α-D-mannose
Other name(s): VTC2; VTC5; GDP-L-galactose phosphorylase
Systematic name: GDP-β-L-galactose/GDP-α-D-glucose:hexose 1-phosphate guanylyltransferase
Comments: This plant enzyme catalyses the conversion of GDP-β-L-galactose and GDP-α-D-glucose to β-L-galactose 1-phosphate and α-D-glucose 1-phosphate, respectively. The enzyme can use inorganic phosphate as the co-substrate, but several hexose 1-phosphates, including α-D-mannose 1-phosphate, α-D-glucose 1-phosphate, and α-D-galactose 1-phosphate, are better guanylyl acceptors. The enzyme's activity on GDP-β-L-galactose is crucial for the biosynthesis of L-ascorbate.
References:
1.  Linster, C.L., Gomez, T.A., Christensen, K.C., Adler, L.N., Young, B.D., Brenner, C. and Clarke, S.G. Arabidopsis VTC2 encodes a GDP-L-galactose phosphorylase, the last unknown enzyme in the Smirnoff-Wheeler pathway to ascorbic acid in plants. J. Biol. Chem. 282 (2007) 18879–18885. [PMID: 17462988]
2.  Dowdle, J., Ishikawa, T., Gatzek, S., Rolinski, S. and Smirnoff, N. Two genes in Arabidopsis thaliana encoding GDP-L-galactose phosphorylase are required for ascorbate biosynthesis and seedling viability. Plant J. 52 (2007) 673–689. [PMID: 17877701]
3.  Wolucka, B.A. and Van Montagu, M. The VTC2 cycle and the de novo biosynthesis pathways for vitamin C in plants: an opinion. Phytochemistry 68 (2007) 2602–2613. [PMID: 17950389]
4.  Laing, W.A., Wright, M.A., Cooney, J. and Bulley, S.M. The missing step of the L-galactose pathway of ascorbate biosynthesis in plants, an L-galactose guanyltransferase, increases leaf ascorbate content. Proc. Natl. Acad. Sci. USA 104 (2007) 9534–9539. [PMID: 17485667]
5.  Linster, C.L., Adler, L.N., Webb, K., Christensen, K.C., Brenner, C. and Clarke, S.G. A second GDP-L-galactose phosphorylase in arabidopsis en route to vitamin C. Covalent intermediate and substrate requirements for the conserved reaction. J. Biol. Chem. 283 (2008) 18483–18492. [PMID: 18463094]
6.  Muller-Moule, P. An expression analysis of the ascorbate biosynthesis enzyme VTC2. Plant Mol. Biol. 68 (2008) 31–41. [PMID: 18516687]
[EC 2.7.7.69 created 2010, modified 2020]
 
 
EC 2.7.7.78     
Accepted name: GDP-D-glucose phosphorylase
Reaction: GDP-α-D-glucose + phosphate = α-D-glucose 1-phosphate + GDP
Systematic name: GDP:α-D-glucose 1-phosphate guanylyltransferase
Comments: The enzyme may be involved in prevention of misincorporation of glucose in place of mannose residues into glycoconjugates i.e. to remove accidentally produced GDP-α-D-glucose. Activities with GDP-L-galactose, GDP-D-mannose and UDP-D-glucose are all less than 3% that with GDP-D-glucose.
References:
1.  Adler, L.N., Gomez, T.A., Clarke, S.G. and Linster, C.L. A novel GDP-D-glucose phosphorylase involved in quality control of the nucleoside diphosphate sugar pool in Caenorhabditis elegans and mammals. J. Biol. Chem. 286 (2011) 21511–21523. [PMID: 21507950]
[EC 2.7.7.78 created 2011]
 
 
EC 2.7.8.6     
Accepted name: undecaprenyl-phosphate galactose phosphotransferase
Reaction: UDP-α-D-galactose + undecaprenyl phosphate = UMP + α-D-galactosyl-diphosphoundecaprenol
Other name(s): poly(isoprenol)-phosphate galactose phosphotransferase; poly(isoprenyl)phosphate galactosephosphatetransferase; undecaprenyl phosphate galactosyl-1-phosphate transferase; UDP-galactose:undecaprenyl-phosphate galactose phosphotransferase
Systematic name: UDP-α-D-galactose:undecaprenyl-phosphate galactose phosphotransferase
References:
1.  Osborn, M.J. and Yuan Tze-Yuen, R. Biosynthesis of bacterial lipopolysaccharide. VII. Enzymatic formation of the first intermediate in biosynthesis of the O-antigen of Salmonella typhimurium. J. Biol. Chem. 243 (1968) 5145–5152. [PMID: 4878433]
2.  Wright, A., Dankert, M., Fennessen, P. and Robbins, P.W. Characterization of a polyisoprenoid compound functional in O-antigen biosynthesis. Proc. Natl. Acad. Sci. USA 57 (1967) 1798–1803. [PMID: 4291948]
[EC 2.7.8.6 created 1972]
 
 
EC 2.7.8.18     
Accepted name: UDP-galactose—UDP-N-acetylglucosamine galactose phosphotransferase
Reaction: UDP-α-D-galactose + UDP-N-acetyl-α-D-glucosamine = UMP + UDP-N-acetyl-6-(α-D-galactose-1-phospho)-α-D-glucosamine
Other name(s): uridine diphosphogalactose-uridine diphosphoacetylglucosamine galactose-1-phosphotransferase; galactose-1-phosphotransferase; galactosyl phosphotransferase; UDP-galactose:UDP-N-acetyl-D-glucosamine galactose phosphotransferase
Systematic name: UDP-α-D-galactose:UDP-N-acetyl-α-D-glucosamine galactose phosphotransferase
Comments: N-Acetylglucosamine end-groups in glycoproteins can also act as acceptors.
References:
1.  Nakanishi, Y., Otsu, K. and Suzuki, S. Enzymatic transfer of galactosyl phosphate from UDP-galactose to UDP-N-acetylglucosamine. FEBS Lett. 151 (1983) 15–18. [PMID: 6130977]
[EC 2.7.8.18 created 1986]
 
 
EC 2.8.2.5     
Accepted name: chondroitin 4-sulfotransferase
Reaction: 3′-phosphoadenylyl sulfate + chondroitin = adenosine 3′,5′-bisphosphate + chondroitin 4′-sulfate
Glossary: 3′-phosphoadenylyl sulfate = PAPS
Other name(s): chondroitin sulfotransferase; 3′-phosphoadenylyl-sulfate:chondroitin 4′-sulfotransferase
Systematic name: 3′-phosphoadenylyl-sulfate:chondroitin 4′-sulfonotransferase
Comments: The sulfation takes place at the 4-position of N-acetyl-galactosamine residues of chondroitin. Not identical with EC 2.8.2.17 chondroitin 6-sulfotransferase.
References:
1.  Habuchi, O. and Miyashita, N. Separation and characterization of chondroitin 6-sulfotransferase and chondroitin 4-sulfotransferase from chick embryo cartilage. Biochim. Biophys. Acta 717 (1982) 414–421. [PMID: 6957247]
2.  Nakanishi, Y., Otsu, K. and Suzuki, S. Enzymatic transfer of galactosyl phosphate from UDP-galactose to UDP-N-acetylglucosamine. FEBS Lett. 151 (1983) 15–18. [PMID: 6130977]
3.  Nakanishi, Y., Shimizu, M., Otsu, K., Kato, S., Tsuji, M. and Suzuki, S. A terminal 6-sulfotransferase catalyzing a synthesis of N-acetylgalactosamine 4,6-bissulfate residue at the nonreducing terminal position of chondroitin sulfate. J. Biol. Chem. 256 (1981) 5443–5449. [PMID: 6787041]
4.  Suzuki, S. and Strominger, J.L. Enzymatic sulfation of mucopolysaccharides in hen oviduct. I. Transfer of sulfate from 3′-phosphoadenosine 5′-phosphosulfate to mucopolysaccharides. J. Biol. Chem. 235 (1960) 257–266. [PMID: 13835879]
5.  Suzuki, S. and Strominger, J.L. Enzymatic sulfation of mucopolysaccharides in hen oviduct. II. Mechanism of the reaction studied with oligosaccharides and monosaccharides as acceptors. J. Biol. Chem. 235 (1960) 267–273. [PMID: 13835880]
6.  Suzuki, S. and Strominger, J.L. Enzymatic sulfation of mucopolysaccharides in hen oviduct. III. Mechanism of sulfation of chondroitin and chondroitin sulfate A. J. Biol. Chem. 235 (1960) 274–276. [PMID: 13835881]
[EC 2.8.2.5 created 1965, modified 1986]
 
 
EC 3.1.3.10     
Accepted name: glucose-1-phosphatase
Reaction: α-D-glucose 1-phosphate + H2O = D-glucose + phosphate
Systematic name: α-D-glucose-1-phosphate phosphohydrolase
Comments: Also acts, more slowly, on D-galactose 1-phosphate.
References:
1.  Faulkner, P. A hexose-1-phosphatase in silkworm blood. Biochem. J. 60 (1955) 590–596. [PMID: 13249953]
2.  Turner, D.H. and Turner, J.F. The hydrolysis of glucose monophosphates by a phosphatase preparation from pea seeds. Biochem. J. 74 (1960) 486–491. [PMID: 13839934]
[EC 3.1.3.10 created 1961]
 
 
EC 3.1.3.93     
Accepted name: L-galactose 1-phosphate phosphatase
Reaction: β-L-galactose 1-phosphate + H2O = L-galactose + phosphate
Other name(s): VTC4 (gene name) (ambiguous); IMPL2 (gene name) (ambiguous)
Systematic name: β-L-galactose-1-phosphate phosphohydrolase
Comments: The enzyme from plants also has the activity of EC 3.1.3.25, inositol-phosphate phosphatase. The enzymes have very low activity with D-galactose 1-phosphate (cf. EC 3.1.3.94, D-galactose 1-phosphate phosphatase).
References:
1.  Laing, W.A., Bulley, S., Wright, M., Cooney, J., Jensen, D., Barraclough, D. and MacRae, E. A highly specific L-galactose-1-phosphate phosphatase on the path to ascorbate biosynthesis. Proc. Natl. Acad. Sci. USA 101 (2004) 16976–16981. [PMID: 15550539]
2.  Torabinejad, J., Donahue, J.L., Gunesekera, B.N., Allen-Daniels, M.J. and Gillaspy, G.E. VTC4 is a bifunctional enzyme that affects myoinositol and ascorbate biosynthesis in plants. Plant Physiol. 150 (2009) 951–961. [PMID: 19339506]
3.  Petersen, L.N., Marineo, S., Mandala, S., Davids, F., Sewell, B.T. and Ingle, R.A. The missing link in plant histidine biosynthesis: Arabidopsis myoinositol monophosphatase-like2 encodes a functional histidinol-phosphate phosphatase. Plant Physiol. 152 (2010) 1186–1196. [PMID: 20023146]
[EC 3.1.3.93 created 2014]
 
 
EC 3.1.3.94     
Accepted name: D-galactose 1-phosphate phosphatase
Reaction: α-D-galactose 1-phosphate + H2O = D-galactose + phosphate
Systematic name: α-D-galactose-1-phosphate phosphohydrolase
Comments: The human enzyme also has the activity of EC 3.1.3.25, inositol-phosphate phosphatase. The enzyme has very low activity with L-galactose 1-phosphate (cf. EC 3.1.3.93, L-galactose 1-phosphate phosphatase).
References:
1.  Parthasarathy, R., Parthasarathy, L. and Vadnal, R. Brain inositol monophosphatase identified as a galactose 1-phosphatase. Brain Res. 778 (1997) 99–106. [PMID: 9462881]
[EC 3.1.3.94 created 2014]
 
 
EC 3.1.6.4     
Accepted name: N-acetylgalactosamine-6-sulfatase
Reaction: Hydrolysis of the 6-sulfate groups of the N-acetyl-D-galactosamine 6-sulfate units of chondroitin sulfate and of the D-galactose 6-sulfate units of keratan sulfate
Other name(s): chondroitin sulfatase; chondroitinase; galactose-6-sulfate sulfatase; acetylgalactosamine 6-sulfatase; N-acetylgalactosamine-6-sulfate sulfatase; N-acetylgalactosamine 6-sulfatase
Systematic name: N-acetyl-D-galactosamine-6-sulfate 6-sulfohydrolase
References:
1.  Epstein, E.H. and Leventhal, M.E. Steroid sulfatase of human leukocytes and epidermis and the diagnosis of recessive X-linked ichthyosis. J. Clin. Invest. 67 (1981) 1257–1262. [PMID: 6939689]
2.  Glössl, J. and Kresse, H. Impaired degradation of keratan sulphate by Morquio A fibroblasts. Biochem. J. 203 (1982) 335–338. [PMID: 6213226]
3.  Lim, C.T. and Horwitz, A.L. Purification and properties of human N-acetylgalactosamine-6-sulfate sulfatase. Biochim. Biophys. Acta 657 (1981) 344–355. [PMID: 7213753]
4.  Sørensen, S.H., Norén, O., Sjöström, H. and Danielsen, E.M. Amphiphilic pig intestinal microvillus maltase/glucoamylase. Structure and specificity. Eur. J. Biochem. 126 (1982) 559–568. [PMID: 6814909]
5.  Yutaka, T., Okada, S., Kato, T., Inui, K. and Yabuchi, H. Galactose 6-sulfate sulfatase activity in Morquio syndrome. Clin. Chim. Acta 122 (1982) 169–180. [PMID: 6809361]
[EC 3.1.6.4 created 1961]
 
 
EC 3.1.6.8     
Accepted name: cerebroside-sulfatase
Reaction: a cerebroside 3-sulfate + H2O = a cerebroside + sulfate
Other name(s): arylsulfatase A; cerebroside sulfate sulfatase
Systematic name: cerebroside-3-sulfate 3-sulfohydrolase
Comments: Hydrolyses galactose-3-sulfate residues in a number of lipids. Also hydrolyses ascorbate 2-sulfate and many phenol sulfates.
References:
1.  Mehl, E. and Jatzkewitz, H. A cerebrosidesulfatase from swine kidney. Hoppe-Seyler's Z. Physiol. Chem. 339 (1964) 260–276. [PMID: 5829234]
2.  Roy, A.B. Sulphatases, lysosomes and disease. Aust. J. Exp. Biol. Med. Sci. 54 (1976) 111–135. [PMID: 13772]
[EC 3.1.6.8 created 1972]
 
 
EC 3.2.1.22     
Accepted name: α-galactosidase
Reaction: Hydrolysis of terminal, non-reducing α-D-galactose residues in α-D-galactosides, including galactose oligosaccharides, galactomannans and galactolipids
Other name(s): melibiase; α-D-galactosidase; α-galactosidase A; α-galactoside galactohydrolase
Systematic name: α-D-galactoside galactohydrolase
Comments: Also hydrolyses α-D-fucosides.
References:
1.  Suzuki, H., Li, S.-C. and Li, Y.-T. α-Galactosidase from Mortierella vinacea. Crystallization and properties. J. Biol. Chem. 245 (1970) 781–786. [PMID: 5418105]
2.  Wiederschain, G. and Beyer, E. [Interrelation of α-D-fucosidase and α-D-galactosidase activities in man and animals] Dokl. Akad. Nauk S.S.S.R. 231 (1976) 486–488. [PMID: 976079]
[EC 3.2.1.22 created 1961]
 
 
EC 3.2.1.23     
Accepted name: β-galactosidase
Reaction: Hydrolysis of terminal non-reducing β-D-galactose residues in β-D-galactosides
Other name(s): lactase (ambiguous); β-lactosidase; maxilact; hydrolact; β-D-lactosidase; S 2107; lactozym; trilactase; β-D-galactanase; oryzatym; sumiklat
Systematic name: β-D-galactoside galactohydrolase
Comments: Some enzymes in this group hydrolyse α-L-arabinosides; some animal enzymes also hydrolyse β-D-fucosides and β-D-glucosides; cf. EC 3.2.1.108 lactase.
References:
1.  Blakely, J.A. and MacKenzie, S.L. Purification and properties of a β-hexosidase from Sporobolomyces singularis. Can. J. Biochem. 47 (1969) 1021–1025. [PMID: 5389663]
2.  Kuby, S.A. and Lardy, H.A. Purification and kinetics of β-D-galactosidase from Escherichia coli, strain K-12. J. Am. Chem. Soc. 75 (1953) 890–896.
3.  Kuo, C.H. and Wells, W.W. β-Galactosidase from rat mammary gland. Its purification, properties, and role in the biosynthesis of 6β-O-D-galactopyranosyl myo-inositol. J. Biol. Chem. 253 (1978) 3550–3556. [PMID: 418065]
4.  Landman, O.E. Properties and induction of β-galactosidase in Bacillus megaterium. Biochim. Biophys. Acta 23 (1957) 558–569. [PMID: 13426167]
5.  Llanillo, M., Perez, N. and Cabezas, J.A. β-Galactosidase and β-glucosidase activities of the same enzyme from rabbit liver. Int. J. Biochem. 8 (1977) 557–564.
6.  Monod, J. and Cohn, M. La biosynthèse induite des enzymes (adaptation enzymatique). Adv. Enzymol. Relat. Subj. Biochem. 13 (1952) 67–119. [PMID: 14943665]
7.  Wallenfels, K. and Malhotra, O.P. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 409–430.
8.  Asp, N.G., Dahlqvist, A. and Koldovský, O. Human small-intestinal β-galactosidases. Separation and characterization of one lactase and one hetero β-galactosidase. Biochem. J. 114 (1969) 351–359. [PMID: 5822067]
[EC 3.2.1.23 created 1961, modified 1980]
 
 
EC 3.2.1.46     
Accepted name: galactosylceramidase
Reaction: a D-galactosyl-N-acylsphingosine + H2O = D-galactose + a ceramide
Glossary: a ceramide = an N-acylsphingosine
Other name(s): cerebroside galactosidase; galactocerebroside.β-galactosidase; galactosylcerebrosidase; galactocerebrosidase; ceramide galactosidase; galactocerebroside galactosidase; galactosylceramide.β-galactosidase; cerebroside β-galactosidase; galactosylceramidase I; β-galactosylceramidase; galactocerebroside-β-D-galactosidase; lactosylceramidase I; β-galactocerebrosidase; lactosylceramidase
Systematic name: D-galactosyl-N-acylsphingosine galactohydrolase
Comments: cf. EC 3.2.1.62 glycosylceramidase.
References:
1.  Brady, R.O., Gal, A.E., Kanfer, J.N. and Bradley, R.M. The metabolism of glucocerebrosides. 3. Purification and properties of a glucosyl- and galactosylceramide-cleaving enzyme from rat intestinal tissue. J. Biol. Chem. 240 (1965) 3766–3770. [PMID: 5320641]
[EC 3.2.1.46 created 1972]
 
 
EC 3.2.1.47      
Deleted entry: galactosylgalactosylglucosylceramidase. Now known to be catalyzed by EC 3.2.1.22, α-galactosidase.
[EC 3.2.1.47 created 1972, modified 2011, deleted 2021]
 
 
EC 3.2.1.62     
Accepted name: glycosylceramidase
Reaction: (1) a β-D-glucosyl-N-acylsphingosine + H2O = a ceramide + β-D-glucose
(2) a β-D-galactosyl-N-acylsphingosine + H2O = a ceramide + β-D-galactose
(3) a flavonoid-O-β-D-glucoside + H2O = a flavonoid + β-D-glucose
Glossary: a ceramide = an N-acylsphingosine
Other name(s): phlorizin hydrolase; phloretin-glucosidase; glycosyl ceramide glycosylhydrolase; cerebrosidase; phloridzin β-glucosidase; lactase-phlorizin hydrolase; phloridzin glucosidase; LPH (gene name); LCT (gene name); glycosyl-N-acylsphingosine glycohydrolase
Systematic name: β-D-glucosyl-N-acylsphingosine glycohydrolase (configuration-retaining)
Comments: The enzyme, found in the intestinal mucosa, hydrolyses β-D-glucosyl and β-D-galactosyl residues from a very broad range of substrates using a retaining mechanism. Characterized substrates include glucosyl- and galactosyl-ceramides [3], O3-, O4′ and O7-glucosylated flavonoids [6], and the 2′-O-glucosylated dihydrochalcone phlorizin [1]. The enzyme includes two glycosyl hydrolase domains, both belonging to the GH1 family. While one domain is responsible for the activity described here, the other catalyses the reaction of EC 3.2.1.108, lactase [4,5]. cf. EC 3.2.1.45, glucosylceramidase and EC 3.2.1.46, galactosylceramidase.
References:
1.  Malathi, P. and Crane, R.K. Phlorizin hydrolase: a β-glucosidase of hamster intestinal brush border membrane. Biochim. Biophys. Acta 173 (1969) 245–256. [PMID: 5774775]
2.  Lorenz-Meyer, H., Blum, A.L., Haemmerli, H.P. and Semenza, G. A second enzyme defect in acquired lactase deficiency: lack of small-intestinal phlorizin-hydrolase. Eur. J. Clin. Invest. 2 (1972) 326–331. [PMID: 5082068]
3.  Leese, H.J. and Semenza, G. On the identity between the small intestinal enzymes phlorizin hydrolase and glycosylceramidase. J. Biol. Chem. 248 (1973) 8170–8173. [PMID: 4752949]
4.  Zecca, L., Mesonero, J.E., Stutz, A., Poiree, J.C., Giudicelli, J., Cursio, R., Gloor, S.M. and Semenza, G. Intestinal lactase-phlorizin hydrolase (LPH): the two catalytic sites; the role of the pancreas in pro-LPH maturation. FEBS Lett. 435 (1998) 225–228. [PMID: 9762914]
5.  Arribas, J.C., Herrero, A.G., Martin-Lomas, M., Canada, F.J., He, S. and Withers, S.G. Differential mechanism-based labeling and unequivocal activity assignment of the two active sites of intestinal lactase/phlorizin hydrolase. Eur. J. Biochem. 267 (2000) 6996–7005. [PMID: 11106409]
6.  Nemeth, K., Plumb, G.W., Berrin, J.G., Juge, N., Jacob, R., Naim, H.Y., Williamson, G., Swallow, D.M. and Kroon, P.A. Deglycosylation by small intestinal epithelial cell β-glucosidases is a critical step in the absorption and metabolism of dietary flavonoid glycosides in humans. Eur J Nutr 42 (2003) 29–42. [PMID: 12594539]
[EC 3.2.1.62 created 1972, modified 1976, modified 2022]
 
 
EC 3.2.1.63     
Accepted name: 1,2-α-L-fucosidase
Reaction: methyl-2-α-L-fucopyranosyl-β-D-galactoside + H2O = L-fucose + methyl β-D-galactoside
Other name(s): almond emulsin fucosidase; α-(1→2)-L-fucosidase
Systematic name: 2-α-L-fucopyranosyl-β-D-galactoside fucohydrolase
Comments: Highly specific for non-reducing terminal L-fucose residues linked to D-galactose residues by a 1,2-α-linkage. Not identical with EC 3.2.1.111 1,3-α-L-fucosidase.
References:
1.  Bahl, O.P. Glycosidases of Aspergillus niger. II. Purification and general properties of 1,2-α-L-fucosidase. J. Biol. Chem. 245 (1970) 299–304. [PMID: 5460888]
2.  Ogata-Arakawa, M., Muramatsu, T. and Kobata, A. α-L-Fucosidases from almond emulsin: characterization of the two enzymes with different specificities. Arch. Biochem. Biophys. 181 (1977) 353–358. [PMID: 18111]
3.  Reglero, A. and Cabezas, J.A. Glycosidases of molluscs. Purification and properties of α-L-fucosidase from Chamelea gallina L. Eur. J. Biochem. 66 (1976) 379–387. [PMID: 7458]
[EC 3.2.1.63 created 1972]
 
 
EC 3.2.1.81     
Accepted name: β-agarase
Reaction: Hydrolysis of (1→4)-β-D-galactosidic linkages in agarose, giving the tetramer as the predominant product
Glossary: agarose = a linear polysaccharide produced by some members of the Rhodophyta (red algae) made up from alternating D-galactose and 3,6-anhydro-α-L-galactopyranose residues joined by α-(1→3)- and β-(1→4)-linkages. In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
neoagarobiose = 3,6-anhydro-α-L-galactopyranosyl-(1→3)-D-galactose
agarobiose = β-D-galactopyranosyl-(1→4)-3,6-anhydro-L-galactose
Other name(s): agarase (ambiguous); AgaA; AgaB; endo-β-agarase; agarose 3-glycanohydrolase (incorrect)
Systematic name: agarose 4-glycanohydrolase
Comments: Also acts on porphyran, but more slowly [1]. This enzyme cleaves the β-(1→4) linkages of agarose in a random manner with retention of the anomeric-bond configuration, producing β-anomers that give rise progressively to α-anomers when mutarotation takes place [6]. The end products of hydrolysis are neoagarotetraose and neoagarohexaose in the case of AgaA from the marine bacterium Zobellia galactanivorans, and neoagarotetraose and neoagarobiose in the case of AgaB [6].
References:
1.  Duckworth, M. and Turvey, J.R. The action of a bacterial agarase on agarose, porphyran and alkali-treated porphyran. Biochem. J. 113 (1969) 687–692. [PMID: 5386190]
2.  Allouch, J., Jam, M., Helbert, W., Barbeyron, T., Kloareg, B., Henrissat, B. and Czjzek, M. The three-dimensional structures of two β-agarases. J. Biol. Chem. 278 (2003) 47171–47180. [PMID: 12970344]
3.  Ohta, Y., Nogi, Y., Miyazaki, M., Li, Z., Hatada, Y., Ito, S. and Horikoshi, K. Enzymatic properties and nucleotide and amino acid sequences of a thermostable β-agarase from the novel marine isolate, JAMB-A94. Biosci. Biotechnol. Biochem. 68 (2004) 1073–1081. [PMID: 15170112]
4.  Ohta, Y., Hatada, Y., Nogi, Y., Miyazaki, M., Li, Z., Akita, M., Hidaka, Y., Goda, S., Ito, S. and Horikoshi, K. Enzymatic properties and nucleotide and amino acid sequences of a thermostable β-agarase from a novel species of deep-sea Microbulbifer. Appl. Microbiol. Biotechnol. 64 (2004) 505–514. [PMID: 15088129]
5.  Sugano, Y., Terada, I., Arita, M., Noma, M. and Matsumoto, T. Purification and characterization of a new agarase from a marine bacterium, Vibrio sp. strain JT0107. Appl. Environ. Microbiol. 59 (1993) 1549–1554. [PMID: 8517750]
6.  Jam, M., Flament, D., Allouch, J., Potin, P., Thion, L., Kloareg, B., Czjzek, M., Helbert, W., Michel, G. and Barbeyron, T. The endo-β-agarases AgaA and AgaB from the marine bacterium Zobellia galactanivorans: two paralogue enzymes with different molecular organizations and catalytic behaviours. Biochem. J. 385 (2005) 703–713. [PMID: 15456406]
[EC 3.2.1.81 created 1972, modified 2006]
 
 
EC 3.2.1.83     
Accepted name: κ-carrageenase
Reaction: Endohydrolysis of (1→4)-β-D-linkages between D-galactose 4-sulfate and 3,6-anhydro-D-galactose in κ-carrageenans
Glossary: In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
ι-neocarrabiose = 3,6-anhydro-2-O-sulfo-α-D-galactopyranosyl-(1→3)-4-O-sulfo-D-galactose
ι-carrabiose = 4-O-sulfo- β-D-galactopyranosyl-(1→4)-3,6-anhydro-2-O-sulfo-D-galactose
Other name(s): κ-carrageenan 4-β-D-glycanohydrolase
Systematic name: κ-carrageenan 4-β-D-glycanohydrolase (configuration-retaining)
Comments: The main products of hydrolysis are neocarrabiose-sulfate and neocarratetraose-sulfate [5]. Unlike EC 3.2.1.157 (ι-carrageenase), but similar to EC 3.2.1.81 (β-agarase), this enzyme proceeds with retention of the anomeric configuration.
References:
1.  Weigl, J. and Yashe, W. The enzymic hydrolysis of carrageenan by Pseudomonas carrageenovora: purification of a κ-carrageenase. Can. J. Microbiol. 12 (1966) 939–947. [PMID: 5972647]
2.  Potin, P., Sanseau, A., Le Gall, Y., Rochas, C. and Kloareg, B. Purification and characterization of a new κ-carrageenase from a marine Cytophaga-like bacterium. Eur. J. Biochem. 201 (1991) 241–247. [PMID: 1915370]
3.  Potin, P., Richard, C., Barbeyron, T., Henrissat, B., Gey, C., Petillot, Y., Forest, E., Dideberg, O., Rochas, C. and Kloareg, B. Processing and hydrolytic mechanism of the cgkA-encoded κ-carrageenase of Alteromonas carrageenovora. Eur. J. Biochem. 228 (1995) 971–975. [PMID: 7737202]
4.  Michel, G., Barbeyron, T., Flament, D., Vernet, T., Kloareg, B. and Dideberg, O. Expression, purification, crystallization and preliminary x-ray analysis of the κ-carrageenase from Pseudoalteromonas carrageenovora. Acta Crystallogr. D Biol. Crystallogr. 55 (1999) 918–920. [PMID: 10089334]
5.  Michel, G., Chantalat, L., Duee, E., Barbeyron, T., Henrissat, B., Kloareg, B. and Dideberg, O. The κ-carrageenase of P. carrageenovora features a tunnel-shaped active site: a novel insight in the evolution of Clan-B glycoside hydrolases. Structure 9 (2001) 513–525. [PMID: 11435116]
[EC 3.2.1.83 created 1972, modified 2006]
 
 
EC 3.2.1.85     
Accepted name: 6-phospho-β-galactosidase
Reaction: a 6-phospho-β-D-galactoside + H2O = 6-phospho-D-galactose + an alcohol
Other name(s): phospho-β-galactosidase; β-D-phosphogalactoside galactohydrolase; phospho-β-D-galactosidase; 6-phospho-β-D-galactosidase
Systematic name: 6-phospho-β-D-galactoside 6-phosphogalactohydrolase
References:
1.  Hengstenberg, W., Penberthy, W.K. and Morse, M.L. Purification of the staphylococcal 6-phospho-β-D-galactosidase. Eur. J. Biochem. 14 (1970) 27–32. [PMID: 5447434]
[EC 3.2.1.85 created 1976]
 
 
EC 3.2.1.87     
Accepted name: capsular-polysaccharide endo-1,3-α-galactosidase
Reaction: Random hydrolysis of (1→3)-α-D-galactosidic linkages in Aerobacter aerogenes capsular polysaccharide
Other name(s): polysaccharide depolymerase; capsular polysaccharide galactohydrolase
Systematic name: Aerobacter-capsular-polysaccharide galactohydrolase
Comments: Hydrolyses the galactosyl-α-1,3-D-galactose linkages only in the complex substrate, bringing about depolymerization.
References:
1.  Yurewicz, E.C., Ghalambor, M.A., Duckworth, D.H. and Heath, E.C. Catalytic and molecular properties of a phage-induced capsular polysaccharide depolymerase. J. Biol. Chem. 246 (1971) 5607–5716. [PMID: 5096084]
2.  Yurewicz, E.C., Ghalambor, M.A. and Heath, E.C. The structure of Aerobacter aerogenes capsular polysaccharide. J. Biol. Chem. 246 (1971) 5596–5606. [PMID: 4328830]
[EC 3.2.1.87 created 1976]
 
 
EC 3.2.1.108     
Accepted name: lactase
Reaction: lactose + H2O = β-D-galactose + D-glucose
Glossary: lactose = β-D-galactopyranosyl-(1→4)-α-D-glucopyranose
Other name(s): lactase-phlorizin hydrolase; LPH (gene name); LCT (gene name)
Systematic name: lactose galactohydrolase (configuration-retaining)
Comments: The enzyme from intestinal mucosa contains two glycosyl hydrolase domains, both of which belong to glycosyl hydrolase family 1 (GH1). While the first domain catalyses the activity described here, the second domain catalyses the reaction of EC 3.2.1.62 glycosylceramidase. cf. EC 3.2.1.33 amylo-α-1,6-glucosidase.
References:
1.  Asp, N.G., Dahlqvist, A. and Koldovský, O. Human small-intestinal β-galactosidases. Separation and characterization of one lactase and one hetero β-galactosidase. Biochem. J. 114 (1969) 351–359. [PMID: 5822067]
2.  Schlegel-Haueter, S., Hore, P., Kerry, K.R. and Semenza, G. The preparation of lactase and glucoamylase of rat small intestine. Biochim. Biophys. Acta 258 (1972) 506–519. [PMID: 5010299]
3.  Lorenz-Meyer, H., Blum, A.L., Haemmerli, H.P. and Semenza, G. A second enzyme defect in acquired lactase deficiency: lack of small-intestinal phlorizin-hydrolase. Eur. J. Clin. Invest. 2 (1972) 326–331. [PMID: 5082068]
4.  Ramaswamay, S. and Radhakrishnan, A.N. Lactase-phlorizin hydrolase complex from monkey small intestine. Purification, properties and evidence for two catalytic sites. Biochim. Biophys. Acta 403 (1975) 446–455. [PMID: 810166]
5.  Skovbjerg, H., Sjöström, H. and Norén, O. Purification and characterization of amphiphilic lactase-phlorizin hydrolase from human small-intestine. Eur. J. Biochem. 114 (1981) 653–661. [PMID: 6786877]
6.  Skovbjerg, H., Norén, O., Sjöström, H., Danielsen, E.M. and Enevoldsen, B.S. Further characterization of intestinal lactase/phlorizin hydrolase. Biochim. Biophys. Acta 707 (1982) 89–97. [PMID: 6814489]
7.  Zecca, L., Mesonero, J.E., Stutz, A., Poiree, J.C., Giudicelli, J., Cursio, R., Gloor, S.M. and Semenza, G. Intestinal lactase-phlorizin hydrolase (LPH): the two catalytic sites; the role of the pancreas in pro-LPH maturation. FEBS Lett. 435 (1998) 225–228. [PMID: 9762914]
8.  Arribas, J.C., Herrero, A.G., Martin-Lomas, M., Canada, F.J., He, S. and Withers, S.G. Differential mechanism-based labeling and unequivocal activity assignment of the two active sites of intestinal lactase/phlorizin hydrolase. Eur. J. Biochem. 267 (2000) 6996–7005. [PMID: 11106409]
[EC 3.2.1.108 created 1984, modified 2022]
 
 
EC 3.2.1.140     
Accepted name: lacto-N-biosidase
Reaction: β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→4)-D-Glc + H2O = β-D-Gal-(1→3)-D-GlcNAc + β-D-Gal-(1→4)-D-Glc
Glossary: β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→4)-D-Glc = lacto-N-tetraose
β-D-Gal-(1→3)-D-GlcNAc = lacto-N-biose
β-D-Gal-(1→4)-D-Glc = lactose
Systematic name: oligosaccharide lacto-N-biosylhydrolase
Comments: The enzyme from Streptomyces specifically hydrolyses the terminal lacto-N-biosyl residue (β-D-Gal-(1→3)-D-GlcNAc) from the non-reducing end of oligosaccharides with the structure β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→R). Lacto-N-hexaose (β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→4)-D-Glc) is hydrolysed to form first lacto-N-tetraose plus lacto-N-biose, with the subsequent formation of lactose. Oligosaccharides in which the non-reducing terminal Gal or the penultimate GlcNAc are replaced by fucose or sialic acid are not substrates. Asialo GM1 tetraose (β-D-Gal-(1→3)-β-D-GalNAc-(1→3)-β-D-Gal-(1→4)-D-Glc) is hydrolysed very slowly, but lacto-N-neotetraose (β-D-Gal-(1→4)-β-D-GalNAc-(1→3)-β-D-Gal-(1→4)-D-Glc) is not a substrate
References:
1.  Sano, M., Hayakawa, K., Kato, I. An enzyme releasing lacto-N-biose from oligosaccharides. Proc. Natl. Acad. Sci. USA 89 (1992) 8512–8516. [PMID: 1528855]
2.  Sano, M., Hayakawa, K., Kato, I. Purification and characterization of an enzyme releasing lacto-N-biose from oligosaccharides with type 1 chain. J. Biol. Chem. 268 (1993) 18560–18566. [PMID: 7689556]
[EC 3.2.1.140 created 1999]
 
 
EC 3.2.1.145     
Accepted name: galactan 1,3-β-galactosidase
Reaction: Hydrolysis of terminal, non-reducing β-D-galactose residues in (1→3)-β-D-galactopyranans
Other name(s): galactan (1→3)-β-D-galactosidase
Systematic name: galactan 3-β-D-galactosidase
Comments: This enzyme removes not only free galactose, but also 6-glycosylated residues, e.g., (1→6)-β-D-galactobiose, and galactose bearing oligosaccharide chains on O-6. Hence, it releases branches from [arabino-galacto-(1→6)]-(1→3)-β-D-galactans.
References:
1.  Tsumuraya, Y., Mochizuki, N. , Hashimoto Y. and Kovac, P. Purification of exo-(1→3)-D-galactanase of Irpex lacteus (Polyporus tulipiferae) and its action on arabinogalactan-proteins. J. Biol. Chem. 265 (1990) 7207–7215. [PMID: 2158993]
2.  Pellerin, P. and Brillouet, J.M. Purification and properties of an exo-(1→3)-β-D-galactanase from Aspergillus niger. Carbohydr. Res. 264 (1994) 281–291. [PMID: 7805066]
[EC 3.2.1.145 created 2001]
 
 
EC 3.2.1.146     
Accepted name: β-galactofuranosidase
Reaction: Hydrolysis of terminal non-reducing β-D-galactofuranosides, releasing galactose
Other name(s): exo-β-galactofuranosidase; exo-β-D-galactofuranosidase; β-D-galactofuranosidase
Systematic name: β-D-galactofuranoside hydrolase
Comments: The enzyme from Helminthosporium sacchari detoxifies helminthosporoside, a bis(digalactosyl)terpene produced by this fungus, by releasing its four molecules of bound galactose.
References:
1.  Rietschel-Berst, M., Jentoft, N.H., Rick, P.D., Pletcher, C., Fang, F. and Gander, J.E. Extracellular exo-β-galactofuranosidase from Penicillium charlesii: isolation, purification, and properties. J. Biol. Chem. 252 (1977) 3219–3226. [PMID: 863879]
2.  Daley, L.S. and Strobel, G.A. β-Galactofuranosidase activity in Helminthosporium sacchari and its relationship to the production of helminthosporoside. Plant Sci. Lett. 30 (1983) 145–154.
3.  Cousin, M.A., Notermans, S., Hoogerhout, P. and Van Boom, J.H. Detection of β-galactofuranosidase production by Penicillium and Aspergillus species using 4-nitrophenyl β-D-galactofuranoside. J. Appl. Bacteriol. 66 (1989) 311–317. [PMID: 2502527]
4.  Miletti, L.C., Marino, C., Marino, K., de Lederkremer, R.M., Colli, W. and Alves, M.J.M. Immobilized 4-aminophenyl-1-thio-β-D-galactofuranoside as a matrix for affinity purification of an exo-β-D-galactofuranosidase. Carbohydr. Res. 320 (1999) 176–182. [PMID: 10573856]
[EC 3.2.1.146 created 2001]
 
 
EC 3.2.1.157     
Accepted name: ι-carrageenase
Reaction: Endohydrolysis of (1→4)-β-D-linkages between D-galactose 4-sulfate and 3,6-anhydro-D-galactose-2-sulfate in ι-carrageenans
Glossary: In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
ι-neocarrabiose = 3,6-anhydro-2-O-sulfo-α-D-galactopyranosyl-(1→3)-4-O-sulfo-D-galactose
ι-carrabiose = 4-O-sulfo-β-D-galactopyranosyl-(1→4)-3,6-anhydro-2-O-sulfo-D-galactose
Systematic name: ι-carrageenan 4-β-D-glycanohydrolase (configuration-inverting)
Comments: The main products of hydrolysis are ι-neocarratetraose sulfate and ι-neocarrahexaose sulfate. ι-Neocarraoctaose is the shortest substrate oligomer that can be cleaved. Unlike EC 3.2.1.81, β-agarase and EC 3.2.1.83, κ-carrageenase, this enzyme proceeds with inversion of the anomeric configuration. ι-Carrageenan differs from κ-carrageenan by possessing a sulfo group on O-2 of the 3,6-anhydro-D-galactose residues, in addition to that present in the κ-compound on O-4 of the D-galactose residues.
References:
1.  Barbeyron, T., Michel, G., Potin, P., Henrissat, B. and Kloareg, B. ι-Carrageenases constitute a novel family of glycoside hydrolases, unrelated to that of κ-carrageenases. J. Biol. Chem. 275 (2000) 35499–35505. [PMID: 10934194]
2.  Michel, G., Chantalat, L., Fanchon, E., Henrissat, B., Kloareg, B. and Dideberg, O. The ι-carrageenase of Alteromonas fortis. A β-helix fold-containing enzyme for the degradation of a highly polyanionic polysaccharide. J. Biol. Chem. 276 (2001) 40202–40209. [PMID: 11493601]
3.  Michel, G., Helbert, W., Kahn, R., Dideberg, O. and Kloareg, B. The structural bases of the processive degradation of ι-carrageenan, a main cell wall polysaccharide of red algae. J. Mol. Biol. 334 (2003) 421–433. [PMID: 14623184]
[EC 3.2.1.157 created 2006]
 
 
EC 3.2.1.158     
Accepted name: α-agarase
Reaction: Endohydrolysis of (1→3)-α-L-galactosidic linkages in agarose, yielding agarotetraose as the major product
Glossary: agarose = a linear polysaccharide produced by some members of the Rhodophyta (red algae) made up from alternating D-galactose and 3,6-anhydro-α-L-galactopyranose residues joined by α-(1→3)- and β-(1→4)-linkages. In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
neoagarobiose = 3,6-anhydro-α-L-galactopyranosyl-(1→3)-D-galactose
agarobiose = β-D-galactopyranosyl-(1→4)-3,6-anhydro-L-galactose
Other name(s): agarase (ambiguous); agaraseA33
Systematic name: agarose 3-glycanohydrolase
Comments: Requires Ca2+. The enzyme from Thalassomonas sp. can use agarose, agarohexaose and neoagarohexaose as substrate. The products of agarohexaose hydrolysis are dimers and tetramers, with agarotetraose being the predominant product, whereas hydrolysis of neoagarohexaose gives rise to two types of trimer. While the enzyme can also hydrolyse the highly sulfated agarose porphyran very efficiently, it cannot hydrolyse the related compounds κ-carrageenan (see EC 3.2.1.83) and ι-carrageenan (see EC 3.2.1.157) [2]. See also EC 3.2.1.81, β-agarase.
References:
1.  Potin, P., Richard, C., Rochas, C. and Kloareg, B. Purification and characterization of the α-agarase from Alteromonas agarlyticus (Cataldi) comb. nov., strain GJ1B. Eur. J. Biochem. 214 (1993) 599–607. [PMID: 8513809]
2.  Ohta, Y., Hatada, Y., Miyazaki, M., Nogi, Y., Ito, S. and Horikoshi, K. Purification and characterization of a novel α-agarase from a Thalassomonas sp. Curr. Microbiol. 50 (2005) 212–216. [PMID: 15902469]
[EC 3.2.1.158 created 2006]
 
 
EC 3.2.1.159     
Accepted name: α-neoagaro-oligosaccharide hydrolase
Reaction: Hydrolysis of the (1→3)-α-L-galactosidic linkages of neoagaro-oligosaccharides that are smaller than a hexamer, yielding 3,6-anhydro-L-galactose and D-galactose
Glossary: In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
neoagarobiose = 3,6-anhydro-α-L-galactopyranosyl-(1→3)-D-galactose
agarobiose = β-D-galactopyranosyl-(1→4)-3,6-anhydro-L-galactose
Other name(s): α-neoagarooligosaccharide hydrolase; α-NAOS hydrolase
Systematic name: α-neoagaro-oligosaccharide 3-glycohydrolase
Comments: When neoagarohexaose is used as a substrate, the oligosaccharide is cleaved at the non-reducing end to produce 3,6-anhydro-L-galactose and agaropentaose, which is further hydrolysed to agarobiose and agarotriose. With neoagarotetraose as substrate, the products are predominantly agarotriose and 3,6-anhydro-L-galactose. In Vibrio sp. the actions of EC 3.2.1.81, β-agarase and EC 3.2.1.159 can be used to degrade agarose to 3,6-anhydro-L-galactose and D-galactose.
References:
1.  Sugano, Y., Kodama, H., Terada, I., Yamazaki, Y. and Noma, M. Purification and characterization of a novel enzyme, α-neoagarooligosaccharide hydrolase (α-NAOS hydrolase), from a marine bacterium, Vibrio sp. strain JT0107. J. Bacteriol. 176 (1994) 6812–6818. [PMID: 7961439]
[EC 3.2.1.159 created 2006]
 
 
EC 3.2.1.164     
Accepted name: galactan endo-1,6-β-galactosidase
Reaction: Endohydrolysis of (1→6)-β-D-galactosidic linkages in arabinogalactan proteins and (1→3):(1→6)-β-galactans to yield galactose and (1→6)-β-galactobiose as the final products
Other name(s): endo-1,6-β-galactanase
Systematic name: endo-β-(1→6)-galactanase
Comments: The enzyme specifically hydrolyses 1,6-β-D-galactooligosaccharides with a degree of polymerization (DP) higher than 3, and their acidic derivatives with 4-O-methylglucosyluronate or glucosyluronate groups at the non-reducing terminals [2]. 1,3-β-D- and 1,4-β-D-galactosyl residues cannot act as substrates. The enzyme can also hydrolyse α-L-arabinofuranosidase-treated arabinogalactan protein (AGP) extracted from radish roots [2,3]. AGPs are thought to be involved in many physiological events, such as cell division, cell expansion and cell death [3].
References:
1.  Brillouet, J.-M., Williams, P. and Moutounet, M. Purification and some properties of a novel endo-β-(1→6)-D-galactanase from Aspergillus niger. Agric. Biol. Chem. 55 (1991) 1565–1571.
2.  Okemoto, K., Uekita, T., Tsumuraya, Y., Hashimoto, Y. and Kasama, T. Purification and characterization of an endo-β-(1→6)-galactanase from Trichoderma viride. Carbohydr. Res. 338 (2003) 219–230. [PMID: 12543554]
3.  Kotake, T., Kaneko, S., Kubomoto, A., Haque, M.A., Kobayashi, H. and Tsumuraya, Y. Molecular cloning and expression in Escherichia coli of a Trichoderma viride endo-β-(1→6)-galactanase gene. Biochem. J. 377 (2004) 749–755. [PMID: 14565843]
[EC 3.2.1.164 created 2007]
 
 
EC 3.2.1.178     
Accepted name: β-porphyranase
Reaction: Hydrolysis of β-D-galactopyranose-(1→4)-α-L-galactopyranose-6-sulfate linkages in porphyran
Other name(s): porphyranase; PorA; PorB; endo-β-porphyranase
Systematic name: porphyran β-D-galactopyranose-(1→4)-α-L-galactopyranose-6-sulfate 4-glycanohydrolase
Comments: The backbone of porphyran consists largely (~70%) of (1→3)-linked β-D-galactopyranose followed by (1→4)-linked α-L-galactopyranose-6-sulfate [the other 30% are mostly agarobiose repeating units of (1→3)-linked β-D-galactopyranose followed by (1→4)-linked 3,6-anhydro-α-L-galactopyranose] [2]. This enzyme cleaves the (1→4) linkages between β-D-galactopyranose and α-L-galactopyranose-6-sulfate, forming mostly the disaccharide α-L-galactopyranose-6-sulfate-(1→3)-β-D-galactose, although some longer oligosaccharides of even number of residues are also observed. Since the enzyme is inactive on the non-sulfated agarose portion of the porphyran backbone, some agarose fragments are also included in the products [1]. Methylation of the D-galactose prevents the enzyme from Zobellia galactanivorans, but not that from Wenyingzhuangia fucanilytica, from binding at subsite -1 [2,3].
References:
1.  Hehemann, J.H., Correc, G., Barbeyron, T., Helbert, W., Czjzek, M. and Michel, G. Transfer of carbohydrate-active enzymes from marine bacteria to Japanese gut microbiota. Nature 464 (2010) 908–912. [PMID: 20376150]
2.  Correc, G., Hehemann, J.H., Czjzek, M. and Helbert, W. Structural analysis of the degradation products of porphyran digested by Zobellia galactanivorans β-porphyranase A. Carbohydrate Polymers 83 (2011) 277–283.
3.  Zhang, Y., Chang, Y., Shen, J., Mei, X. and Xue, C. Characterization of a novel porphyranase accommodating methyl-galactoses at its subsites. J. Agr. Food Chem. 68 (2020) 7032–7039. [PMID: 32520542]
[EC 3.2.1.178 created 2011]
 
 
EC 3.2.1.179     
Accepted name: gellan tetrasaccharide unsaturated glucuronosyl hydrolase
Reaction: β-D-4-deoxy-Δ4-GlcAp-(1→4)-β-D-Glcp-(1→4)-α-L-Rhap-(1→3)-D-Glcp + H2O = 5-dehydro-4-deoxy-D-glucuronate + β-D-Glcp-(1→4)-α-L-Rhap-(1→3)-D-Glcp
Glossary: 5-dehydro-4-deoxy-D-glucuronate = (4S,5R)-4,5-dihydroxy-2,6-dioxohexanoate
β-D-4-deoxy-Δ4-GlcAp-(1→3)-D-GalNAc = 3-(4-deoxy-β-D-gluc-4-enuronosyl)-N-acetyl-D-galactosamine = 3-(4-deoxy-α-L-threo-hex-4-enopyranosyluronic acid)-2-acetamido-2-deoxy-D-galactose
Other name(s): UGL (ambiguous); unsaturated glucuronyl hydrolase (ambiguous); gellan tetrasaccharide unsaturated glucuronyl hydrolase
Systematic name: β-D-4-deoxy-Δ4-GlcAp-(1→4)-β-D-Glcp-(1→4)-α-L-Rhap-(1→3)-D-Glcp β-D-4-deoxy-Δ4-GlcAp hydrolase
Comments: The enzyme releases 4-deoxy-4(5)-unsaturated D-glucuronic acid from oligosaccharides produced by polysaccharide lyases, e.g. the tetrasaccharide β-D-4-deoxy-Δ4-GlcAp-(1→4)-β-D-Glcp-(1→4)-α-L-Rhap-(1→3)-D-Glcp produced by EC 4.2.2.25, gellan lyase. The enzyme can also hydrolyse unsaturated chondroitin and hyaluronate disaccharides (β-D-4-deoxy-Δ4-GlcAp-(1→3)-D-GalNAc, β-D-4-deoxy-Δ4-GlcAp-(1→3)-D-GalNAc6S, β-D-4-deoxy-Δ4-GlcAp2S-(1→3)-D-GalNAc, β-D-4-deoxy-Δ4-GlcAp-(1→3)-D-GlcNAc), preferring the unsulfated disaccharides to the sulfated disaccharides.
References:
1.  Itoh, T., Akao, S., Hashimoto, W., Mikami, B. and Murata, K. Crystal structure of unsaturated glucuronyl hydrolase, responsible for the degradation of glycosaminoglycan, from Bacillus sp. GL1 at 1.8 Å resolution. J. Biol. Chem. 279 (2004) 31804–31812. [PMID: 15148314]
2.  Hashimoto, W., Kobayashi, E., Nankai, H., Sato, N., Miya, T., Kawai, S. and Murata, K. Unsaturated glucuronyl hydrolase of Bacillus sp. GL1: novel enzyme prerequisite for metabolism of unsaturated oligosaccharides produced by polysaccharide lyases. Arch. Biochem. Biophys. 368 (1999) 367–374. [PMID: 10441389]
3.  Itoh, T., Hashimoto, W., Mikami, B. and Murata, K. Substrate recognition by unsaturated glucuronyl hydrolase from Bacillus sp. GL1. Biochem. Biophys. Res. Commun. 344 (2006) 253–262. [PMID: 16630576]
[EC 3.2.1.179 created 2011, modified 2016]
 
 
EC 3.6.3.17      
Transferred entry: monosaccharide-transporting ATPase. Now covered by various ABC-type monosaccharide transporters in sub-subclass EC 7.5.2.
[EC 3.6.3.17 created 2000, deleted 2019]
 
 
EC 3.6.3.18      
Transferred entry: oligosaccharide-transporting ATPase. Now EC 7.5.2.2, ABC-type oligosaccharide transporter
[EC 3.6.3.18 created 2000, deleted 2018]
 
 
EC 3.13.1.1     
Accepted name: UDP-sulfoquinovose synthase
Reaction: UDP-α-D-sulfoquinovopyranose + H2O = UDP-α-D-glucose + sulfite
Other name(s): sulfite:UDP-glucose sulfotransferase; UDPsulfoquinovose synthase; UDP-6-sulfo-6-deoxyglucose sulfohydrolase
Systematic name: UDP-6-sulfo-6-deoxy-α-D-glucose sulfohydrolase
Comments: Requires NAD+, which appears to oxidize UDP-α-D-glucose to UDP-4-dehydroglucose, which dehydrates to UDP-4-dehydro-6-deoxygluc-5-enose, to which sulfite is added. The reaction is completed when the substrate is rehydrogenated at C-4. The enzyme from Arabidopsis thaliana is specific for UDP-Glc and sulfite.
References:
1.  Essigmann, B., Gler, S., Narang, R.A., Linke, D. and Benning, C. Phosphate availability affects the thylakoid lipid composition and the expression of SQD1, a gene required for sulfolipid biosynthesis in Arabidopsis thaliana. Proc. Natl. Acad. Sci. USA 95 (1998) 1950–1955. [PMID: 9465123]
2.  Essigmann, B., Hespenheide, B.M., Kuhn, L.A. and Benning, C. Prediction of the active-site structure and NAD+ binding in SQD1, a protein essential for sulfolipid biosynthesis in Arabidopsis. Arch. Biochem. Biophys. 369 (1999) 30–41. [PMID: 10462438]
3.  Mulichak, A.M., Theisen, M.J., Essigmann, B., Benning, C. and Garavito, R.M. Crystal structure of SQD1, an enzyme involved in the biosynthesis of the plant sulfolipid headgroup donor UDP-sulfoquinovose. Proc. Natl. Acad. Sci. USA 96 (1999) 13097–13102. [PMID: 10557279]
4.  Sanda, S., Leustek, T., Theisen, M., Garavito, R.M. and Benning, C. Recombinant Arabidopsis SQD1 converts UDP-glucose and sulfite to the sulfolipid head group precursor UDP-sulfoquinovose in vitro. J. Biol. Chem. 276 (2001) 3941–3946. [PMID: 11073956]
[EC 3.13.1.1 created 2001, modified 2010]
 
 
EC 4.1.2.21     
Accepted name: 2-dehydro-3-deoxy-6-phosphogalactonate aldolase
Reaction: 2-dehydro-3-deoxy-6-phospho-D-galactonate = pyruvate + D-glyceraldehyde 3-phosphate
Other name(s): 6-phospho-2-keto-3-deoxygalactonate aldolase; phospho-2-keto-3-deoxygalactonate aldolase; 2-keto-3-deoxy-6-phosphogalactonic aldolase; phospho-2-keto-3-deoxygalactonic aldolase; 2-keto-3-deoxy-6-phosphogalactonic acid aldolase; (KDPGal)aldolase; 2-dehydro-3-deoxy-D-galactonate-6-phosphate D-glyceraldehyde-3-phosphate-lyase; 2-dehydro-3-deoxy-D-galactonate-6-phosphate D-glyceraldehyde-3-phosphate-lyase (pyruvate-forming)
Systematic name: 2-dehydro-3-deoxy-6-phospho-D-galactonate D-glyceraldehyde-3-phospho-lyase (pyruvate-forming)
Comments: The enzyme catalyses the last reaction in a D-galactose degradation pathway. cf. EC 4.1.2.55, 2-dehydro-3-deoxy-phosphogluconate/2-dehydro-3-deoxy-6-phosphogalactonate aldolase.
References:
1.  Shuster, C.W. 2-Keto-3-deoxy-6-phosphogalactonic acid aldolase. Methods Enzymol. 9 (1966) 524–528.
[EC 4.1.2.21 created 1972, modified 2014]
 
 
EC 4.1.2.40     
Accepted name: tagatose-bisphosphate aldolase
Reaction: D-tagatose 1,6-bisphosphate = glycerone phosphate + D-glyceraldehyde 3-phosphate
Glossary: glycerone phosphate = dihydroxyacetone phosphate = 3-hydroxy-2-oxopropyl phosphate
Other name(s): D-tagatose-1,6-bisphosphate triosephosphate lyase
Systematic name: D-tagatose 1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase (glycerone-phosphate-forming)
Comments: Enzyme activity is stimulated by certain divalent cations. It is involved in the tagatose 6-phosphate pathway of lactose catabolism in bacteria.
References:
1.  Anderson, R.L. and Markwell, J.P. D-Tagatose-1,6-bisphosphate aldolase (class II) from Klebsiella pneumoniae. Methods Enzymol. 90 (1982) 232–234. [PMID: 6759854]
2.  Van Rooijen, R.J., Van Schalkwijk, S., De Vos, W.M. Molecular cloning, characterization, and nucleotide sequence of the tagatose 6-phosphate pathway gene cluster of the lactose operon of Lactococcus lactis. J. Biol. Chem. 266 (1991) 7176–7181. [PMID: 1901863]
[EC 4.1.2.40 created 1999]
 
 
EC 4.1.2.51     
Accepted name: 2-dehydro-3-deoxy-D-gluconate aldolase
Reaction: 2-dehydro-3-deoxy-D-gluconate = pyruvate + D-glyceraldehyde
Other name(s): Pto1279 (gene name); KDGA; KDG-specific aldolase
Systematic name: 2-dehydro-3-deoxy-D-gluconate D-glyceraldehyde-lyase (pyruvate-forming)
Comments: The enzyme from the archaeon Picrophilus torridus is involved in D-glucose and D-galactose catabolism via the nonphosphorylative variant of the Entner-Doudoroff pathway. In the direction of aldol synthesis the enzyme catalyses the formation of 2-dehydro-3-deoxy-D-gluconate and 2-dehydro-3-deoxy-D-galactonate at a similar ratio. It shows no activity with 2-dehydro-3-deoxy-D-gluconate 6-phosphate. cf. EC 4.1.2.14, 2-dehydro-3-deoxy-phosphogluconate aldolase.
References:
1.  Reher, M., Fuhrer, T., Bott, M. and Schonheit, P. The nonphosphorylative Entner-Doudoroff pathway in the thermoacidophilic euryarchaeon Picrophilus torridus involves a novel 2-keto-3-deoxygluconate- specific aldolase. J. Bacteriol. 192 (2010) 964–974. [PMID: 20023024]
[EC 4.1.2.51 created 2013]
 
 
EC 4.1.2.55     
Accepted name: 2-dehydro-3-deoxy-phosphogluconate/2-dehydro-3-deoxy-6-phosphogalactonate aldolase
Reaction: (1) 2-dehydro-3-deoxy-6-phospho-D-gluconate = pyruvate + D-glyceraldehyde 3-phosphate
(2) 2-dehydro-3-deoxy-6-phospho-D-galactonate = pyruvate + D-glyceraldehyde 3-phosphate
Other name(s): 2-keto-3-deoxygluconate aldolase (ambiguous); KDGA (ambiguous)
Systematic name: 2-dehydro-3-deoxy-6-phospho-D-gluconate/2-dehydro-3-deoxy-6-phospho-D-galactonate D-glyceraldehyde-3-phosphate-lyase (pyruvate-forming)
Comments: In the archaeon Sulfolobus solfataricus the enzyme is involved in glucose and galactose catabolism via the branched variant of the Entner-Doudoroff pathway. It utilizes 2-dehydro-3-deoxy-6-phosphate-D-gluconate and 2-dehydro-3-deoxy-6-phosphate-D-galactonate with similar catalytic efficiency. In vitro the enzyme can also catalyse the cleavage of the non-phosphorylated forms 2-dehydro-3-deoxy-D-gluconate and 2-dehydro-3-deoxy-D-galactonate with much lower catalytic efficiency. cf. EC 4.1.2.21, 2-dehydro-3-deoxy-6-phosphogalactonate aldolase, and EC 4.1.2.14, 2-dehydro-3-deoxy-phosphogluconate aldolase.
References:
1.  Buchanan, C.L., Connaris, H., Danson, M.J., Reeve, C.D. and Hough, D.W. An extremely thermostable aldolase from Sulfolobus solfataricus with specificity for non-phosphorylated substrates. Biochem. J. 343 (1999) 563–570. [PMID: 10527934]
2.  Lamble, H.J., Theodossis, A., Milburn, C.C., Taylor, G.L., Bull, S.D., Hough, D.W. and Danson, M.J. Promiscuity in the part-phosphorylative Entner-Doudoroff pathway of the archaeon Sulfolobus solfataricus. FEBS Lett. 579 (2005) 6865–6869. [PMID: 16330030]
3.  Wolterink-van Loo, S., van Eerde, A., Siemerink, M.A., Akerboom, J., Dijkstra, B.W. and van der Oost, J. Biochemical and structural exploration of the catalytic capacity of Sulfolobus KDG aldolases. Biochem. J. 403 (2007) 421–430. [PMID: 17176250]
[EC 4.1.2.55 created 2014]
 
 
EC 4.2.1.6     
Accepted name: galactonate dehydratase
Reaction: D-galactonate = 2-dehydro-3-deoxy-D-galactonate + H2O
Other name(s): D-galactonate dehydrase; D-galactonate dehydratase; D-galactonate hydro-lyase
Systematic name: D-galactonate hydro-lyase (2-dehydro-3-deoxy-D-galactonate-forming)
Comments: The enzyme shows no activity with D-gluconate [2]. cf. EC 4.2.1.140, gluconate/galactonate dehydratase.
References:
1.  De Ley, J. and Doudoroff, M. The metabolism of D-galactose in Pseudomonas saccharophila. J. Biol. Chem. 227 (1957) 745–757. [PMID: 13462997]
2.  Donald, A., Sibley, D., Lyons, D.E. and Dahms, A.S. D-Galactonate dehydrase. Purification and properties. J. Biol. Chem. 254 (1979) 2132–2137. [PMID: 422572]
[EC 4.2.1.6 created 1961]
 
 
EC 4.2.1.76     
Accepted name: UDP-glucose 4,6-dehydratase
Reaction: UDP-α-D-glucose = UDP-4-dehydro-6-deoxy-α-D-glucose + H2O
Other name(s): UDP-D-glucose-4,6-hydrolyase; UDP-D-glucose oxidoreductase; UDP-glucose 4,6-hydro-lyase
Systematic name: UDP-α-D-glucose 4,6-hydro-lyase (UDP-4-dehydro-6-deoxy-α-D-glucose-forming)
References:
1.  Kamsteeg, J., van Brederode, J. and van Nigtevecht, G. The formation of UDP-L-rhamnose from UDP-D-glucose by an enzyme preparation of red campion (Silene dioica (L) Clairv) leaves. FEBS Lett. 91 (1978) 281–284. [PMID: 680134]
[EC 4.2.1.76 created 1984]
 
 
EC 4.2.1.115     
Accepted name: UDP-N-acetylglucosamine 4,6-dehydratase (configuration-inverting)
Reaction: UDP-N-acetyl-α-D-glucosamine = UDP-2-acetamido-2,6-dideoxy-β-L-arabino-hex-4-ulose + H2O
Glossary: pseudaminic acid = 5,7-bis(acetylamino)-3,5,7,9-tetradeoxy-L-glycero-α-L-manno-2-nonulopyranosonic acid
Other name(s): FlaA1; UDP-N-acetylglucosamine 5-inverting 4,6-dehydratase; PseB; UDP-N-acetylglucosamine hydro-lyase (inverting; UDP-2-acetamido-2,6-dideoxy-β-L-arabino-hex-4-ulose-forming)
Systematic name: UDP-N-acetyl-α-D-glucosamine hydro-lyase (inverting; UDP-2-acetamido-2,6-dideoxy-β-L-arabino-hex-4-ulose-forming)
Comments: Contains NADP+ as a cofactor. This is the first enzyme in the biosynthetic pathway of pseudaminic acid [3], a sialic-acid-like sugar that is unique to bacteria and is used by Helicobacter pylori to modify its flagellin. This enzyme plays a critical role in H. pylori’s pathogenesis, being involved in the synthesis of both functional flagella and lipopolysaccharides [1,2]. It is completely inhibited by UDP-α-D-galactose. The reaction results in the chirality of the C-5 atom being inverted. It is thought that Lys-133 acts sequentially as a catalytic acid, protonating the C-6 hydroxy group and as a catalytic base, abstracting the C-5 proton, resulting in the elimination of water. This enzyme belongs to the short-chain dehydrogenase/reductase family of enzymes.
References:
1.  Ishiyama, N., Creuzenet, C., Miller, W.L., Demendi, M., Anderson, E.M., Harauz, G., Lam, J.S. and Berghuis, A.M. Structural studies of FlaA1 from Helicobacter pylori reveal the mechanism for inverting 4,6-dehydratase activity. J. Biol. Chem. 281 (2006) 24489–24495. [PMID: 16651261]
2.  Schirm, M., Soo, E.C., Aubry, A.J., Austin, J., Thibault, P. and Logan, S.M. Structural, genetic and functional characterization of the flagellin glycosylation process in Helicobacter pylori. Mol. Microbiol. 48 (2003) 1579–1592. [PMID: 12791140]
3.  Schoenhofen, I.C., McNally, D.J., Brisson, J.R. and Logan, S.M. Elucidation of the CMP-pseudaminic acid pathway in Helicobacter pylori: synthesis from UDP-N-acetylglucosamine by a single enzymatic reaction. Glycobiology 16 (2006) 8C–14C. [PMID: 16751642]
[EC 4.2.1.115 created 2009]
 
 
EC 4.2.1.140     
Accepted name: gluconate/galactonate dehydratase
Reaction: (1) D-gluconate = 2-dehydro-3-deoxy-D-gluconate + H2O
(2) D-galactonate = 2-dehydro-3-deoxy-D-galactonate + H2O
Other name(s): gluconate dehydratase (ambiguous); Sso3198 (gene name); Pto0485 (gene name)
Systematic name: D-gluconate/D-galactonate hydro-lyase
Comments: The enzyme is involved in glucose and galactose catabolism via the nonphosphorylative variant of the Entner-Doudoroff pathway in Picrophilus torridus [3] and via the branched variant of the Entner-Doudoroff pathway in Sulfolobus solfataricus [1,2]. In vitro it utilizes D-gluconate with 6-10 fold higher catalytic efficiency than D-galactonate [1,3]. It requires Mg2+ for activity [1,2]. cf. EC 4.2.1.6, galactonate dehydratase, and EC 4.2.1.39, gluconate dehydratase.
References:
1.  Lamble, H.J., Milburn, C.C., Taylor, G.L., Hough, D.W. and Danson, M.J. Gluconate dehydratase from the promiscuous Entner-Doudoroff pathway in Sulfolobus solfataricus. FEBS Lett. 576 (2004) 133–136. [PMID: 15474024]
2.  Ahmed, H., Ettema, T.J., Tjaden, B., Geerling, A.C., van der Oost, J. and Siebers, B. The semi-phosphorylative Entner-Doudoroff pathway in hyperthermophilic archaea: a re-evaluation. Biochem. J. 390 (2005) 529–540. [PMID: 15869466]
3.  Reher, M., Fuhrer, T., Bott, M. and Schonheit, P. The nonphosphorylative Entner-Doudoroff pathway in the thermoacidophilic euryarchaeon Picrophilus torridus involves a novel 2-keto-3-deoxygluconate- specific aldolase. J. Bacteriol. 192 (2010) 964–974. [PMID: 20023024]
[EC 4.2.1.140 created 2013]
 
 
EC 5.1.3.2     
Accepted name: UDP-glucose 4-epimerase
Reaction: UDP-α-D-glucose = UDP-α-D-galactose
Other name(s): UDP-galactose 4-epimerase; uridine diphosphoglucose epimerase; galactowaldenase; UDPG-4-epimerase; uridine diphosphate galactose 4-epimerase; uridine diphospho-galactose-4-epimerase; UDP-glucose epimerase; 4-epimerase; uridine diphosphoglucose 4-epimerase; uridine diphosphate glucose 4-epimerase; UDP-D-galactose 4-epimerase
Systematic name: UDP-α-D-glucose 4-epimerase
Comments: Requires NAD+. Also acts on UDP-2-deoxyglucose.
References:
1.  Leloir, L.F. Enzymic isomerization and related processes. Adv. Enzymol. Relat. Subj. Biochem. 14 (1953) 193–218. [PMID: 13057717]
2.  Maxwell, E.S. and de Robichon-Szulmajster, H. Purification of uridine diphosphate galactose-4-epimerase from yeast and the identification of protein-bound diphosphopyridine nucleotide. J. Biol. Chem. 235 (1960) 308–312.
3.  Wilson, D.B. and Hogness, D.S. The enzymes of the galactose operon in Escherichia coli. I. Purification and characterization of uridine diphosphogalactose 4-epimerase. J. Biol. Chem. 239 (1964) 2469–2481. [PMID: 14235524]
[EC 5.1.3.2 created 1961]
 
 
EC 5.1.3.3     
Accepted name: aldose 1-epimerase
Reaction: α-D-glucose = β-D-glucose
Other name(s): mutarotase; aldose mutarotase; galactose mutarotase; galactose 1-epimerase; D-galactose 1-epimerase
Systematic name: aldose 1-epimerase
Comments: Also acts on L-arabinose, D-xylose, D-galactose, maltose and lactose. This enzyme catalyses the first step in galactose metabolism by converting β-D-galactose into α-D-galactose, which is the substrate for EC 2.7.1.6, galactokinase [5,6].
References:
1.  Bentley, R. and Bhate, D.S. Mutarotase from Penicillium notatum. I. Purification, assay, and general properties of the enzyme. J. Biol. Chem. 235 (1960) 1219–1224. [PMID: 13799037]
2.  Bentley, R. and Bhate, D.S. Mutarotase from Penicillium notatum. II. The mechanism of the mutarotation reaction. J. Biol. Chem. 235 (1960) 1225–1233. [PMID: 13799038]
3.  Keilin, D. and Hartree, E.F. Biological catalysis of mutarotation of glucose. Biochem. J. 50 (1952) 341–348. [PMID: 14915955]
4.  Levy, G.B. and Cook, E.S. A rotographic study of mutarotase. Biochem. J. 57 (1954) 50–55. [PMID: 13159947]
5.  Beebe, J.A. and Frey, P.A. Galactose mutarotase: purification, characterization, and investigations of two important histidine residues. Biochemistry 37 (1998) 14989–14997. [PMID: 9778377]
6.  Thoden, J.B., Timson, D.J., Reece, R.J. and Holden, H.M. Molecular structure of human galactose mutarotase. J. Biol. Chem. 279 (2004) 23431–23437. [PMID: 15026423]
7.  Thoden, J.B., Kim, J., Raushel, F.M. and Holden, H.M. The catalytic mechanism of galactose mutarotase. Protein Sci. 12 (2003) 1051–1059. [PMID: 12717027]
[EC 5.1.3.3 created 1961]
 
 
EC 5.1.3.18     
Accepted name: GDP-mannose 3,5-epimerase
Reaction: (1) GDP-α-D-mannose = GDP-β-L-galactose
(2) GDP-α-D-mannose = GDP-β-L-gulose
Other name(s): GME (gene name); GDP-D-mannose:GDP-L-galactose epimerase; guanosine 5′-diphosphate D-mannose:guanosine 5′-diphosphate L-galactose epimerase
Systematic name: GDP-α-D-mannose 3,5-epimerase
Comments: The enzyme catalyses the formation of the stable intermediate GDP-β-L-gulose as well as GDP-β-L-galactose. The reaction proceeds by C4′ oxidation of GDP-α-D-mannose followed by epimerization of the C5′ position to give GDP-β-L-4-dehydro-gulose. This intermediate is either reduced to give GDP-β-L-gulose or the C3′ position is epimerized to give GDP-β-L-4-dehydro-galactose, followed by C4′ reduction to yield GDP-β-L-galactose. Both products serve as intermediates in two different variants of plant L-ascorbate biosynthesis pathways.
References:
1.  Hebda, P.A., Behrman, E.J. and Barber, G.A. The guanosine 5′-diphosphate D-mannose: guanosine 5′-diphosphate L-galactose epimerase of Chlorella pyrenoidosa. Chemical synthesis of guanosine 5′-diphosphate L-galactose and further studies of the enzyme and the reaction it catalyzes. Arch. Biochem. Biophys. 194 (1979) 496–502. [PMID: 443816]
2.  Barber, G.A. and Hebda, P.A. GDP-D-mannose: GDP-L-galactose epimerase from Chlorella pyrenoidosa. Methods Enzymol. 83 (1982) 522–525. [PMID: 7098948]
3.  Wolucka, B.A., Persiau, G., Van Doorsselaere, J., Davey, M.W., Demol, H., Vandekerckhove, J., Van Montagu, M., Zabeau, M. and Boerjan, W. Partial purification and identification of GDP-mannose 3",5"-epimerase of Arabidopsis thaliana, a key enzyme of the plant vitamin C pathway. Proc. Natl. Acad. Sci. USA 98 (2001) 14843–14848. [PMID: 11752432]
4.  Major, L.L., Wolucka, B.A. and Naismith, J.H. Structure and function of GDP-mannose-3′,5′-epimerase: an enzyme which performs three chemical reactions at the same active site. J. Am. Chem. Soc. 127 (2005) 18309–18320. [PMID: 16366586]
5.  Watanabe, K., Suzuki, K. and Kitamura, S. Characterization of a GDP-D-mannose 3′′,5′′-epimerase from rice. Phytochemistry 67 (2006) 338–346. [PMID: 16413588]
[EC 5.1.3.18 created 1986, modified 2020]
 
 
EC 5.1.3.21     
Accepted name: maltose epimerase
Reaction: α-maltose = β-maltose
Systematic name: maltose 1-epimerase
Comments: The enzyme catalyses the interconversion of α and β anomers of maltose more effectively than those of disaccharides such as lactose and cellobiose.
References:
1.  Shirokane, Y. and Suzuki, M. A novel enzyme, maltose 1-epimerase from Lactobacillus brevis IFO 3345. FEBS Lett. 367 (1995) 177–179. [PMID: 7796915]
[EC 5.1.3.21 created 2002]
 
 
EC 5.1.3.43     
Accepted name: sulfoquinovose mutarotase
Reaction: 6-sulfo-α-D-quinovose = 6-sulfo-β-D-quinovose
Systematic name: 6-sulfo-D-quinovose 1-epimerase
Comments: The enzyme is found in bacteria that possess sulfoglycolytic pathways. The enzyme can also act on other aldohexoses such as D-galactose, D-glucose, D-glucose-6-phosphate, and D-glucuronate, but with lower efficiency. Does not act on D-mannose.
References:
1.  Abayakoon, P., Lingford, J.P., Jin, Y., Bengt, C., Davies, G.J., Yao, S., Goddard-Borger, E.D. and Williams, S.J. Discovery and characterization of a sulfoquinovose mutarotase using kinetic analysis at equilibrium by exchange spectroscopy. Biochem. J. 475 (2018) 1371–1383. [PMID: 29535276]
[EC 5.1.3.43 created 2019]
 
 
EC 5.3.1.4     
Accepted name: L-arabinose isomerase
Reaction: β-L-arabinopyranose = L-ribulose
Other name(s): L-arabinose ketol-isomerase; araA (gene name)
Systematic name: β-L-arabinopyranose aldose-ketose-isomerase
Comments: Requires a divalent metal ion (the enzyme from the bacterium Escherichia coli prefers Mn2+) [2]. The enzyme binds β-L-arabinopyranose [4] and catalyses ring opening to generate a form of open-chain conformation that facilitates the isomerization reaction, which proceeds via an ene-diol mechanism [6]. The enzyme can also convert α-D-galactose to D-tagatose with lower efficiency [5].
References:
1.  Heath, E.C., Horecker, B.L., Smyrniotis, P.Z. and Takagi, Y. Pentose formation by Lactobacillus plantarum. II. L-Arabinose isomerase. J. Biol. Chem. 231 (1958) 1031–1037. [PMID: 13539034]
2.  Patrick, J.W. and Lee, N. Purification and properties of an L-arabinose isomerase from Escherichia coli. J. Biol. Chem. 243 (1968) 4312–4318. [PMID: 4878429]
3.  Nakamatu, T. and Yamanaka, K. Crystallization and properties of L-arabinose isomerase from Lactobacillus gayonii. Biochim. Biophys. Acta 178 (1969) 156–165. [PMID: 5773448]
4.  Schray, K.J. and Rose, I.A. Anomeric specificity and mechanism of two pentose isomerases. Biochemistry 10 (1971) 1058–1062. [PMID: 5550812]
5.  Cheetham, P.S.J. and Wootton, A.N. Bioconversion of D-galactose into D-tagatose. Enzyme and Microbial Technology 15 (1993) 105–108.
6.  Banerjee, S., Anderson, F. and Farber, G.K. The evolution of sugar isomerases. Protein Eng. 8 (1995) 1189–1195. [PMID: 8869631]
7.  Manjasetty, B.A. and Chance, M.R. Crystal structure of Escherichia coli L-arabinose isomerase (ECAI), the putative target of biological tagatose production. J. Mol. Biol. 360 (2006) 297–309. [PMID: 16756997]
[EC 5.3.1.4 created 1961, modified 2022]
 
 
EC 5.3.1.25     
Accepted name: L-fucose isomerase
Reaction: L-fucopyranose = L-fuculose
Systematic name: L-fucose aldose-ketose-isomerase
Comments: Requires a divalent metal ion (the enzyme from the bacterium Escherichia coli prefers Mn2+). The enzyme binds the closed form of the sugar and catalyses ring opening to generate a form of open-chain conformation that facilitates the isomerization reaction, which proceeds via an ene-diol mechanism [3]. The enzyme from Escherichia coli can also convert D-arabinose to D-ribulose [1]. The enzyme from the thermophilic bacterium Caldicellulosiruptor saccharolyticus also converts D-altrose to D-psicose and L-galactose to L-tagatose [4].
References:
1.  Green, M. and Cohen, S.S. Enzymatic conversion of L-fucose to L-fuculose. J. Biol. Chem. 219 (1956) 557–568. [PMID: 13319278]
2.  Lu, Z., Lin, E.C.C. The nucleotide sequence of Escherichia coli genes for L-fucose dissimilation. Nucleic Acids Res. 17 (1989) 4883–4884. [PMID: 2664711]
3.  Seemann, J.E. and Schulz, G.E. Structure and mechanism of L-fucose isomerase from Escherichia coli. J. Mol. Biol. 273 (1997) 256–268. [PMID: 9367760]
4.  Ju, Y.H. and Oh, D.K. Characterization of a recombinant L-fucose isomerase from Caldicellulosiruptor saccharolyticus that isomerizes L-fucose, D-arabinose, D-altrose, and L-galactose. Biotechnol. Lett. 32 (2010) 299–304. [PMID: 19856146]
[EC 5.3.1.25 created 1999]
 
 
EC 5.3.1.26     
Accepted name: galactose-6-phosphate isomerase
Reaction: D-galactose 6-phosphate = D-tagatose 6-phosphate
Systematic name: D-galactose-6-phosphate aldose-ketose-isomerase
Comments: Involved in the tagatose 6-phosphate pathway of lactose catabolism in bacteria.
References:
1.  De Vos, W.M., Boerrigter, I., Van Rooijen, R.J., Reiche, B., Hengstenberg, W. Characterization of the lactose-specific enzymes of the phosphotransferase system in Lactococcus lactis. J. Biol. Chem. 265 (1990) 22554–22560. [PMID: 2125052]
2.  Van Rooijen, R.J., Van Schalkwijk, S., De Vos, W.M. Molecular cloning, characterization, and nucleotide sequence of the tagatose 6-phosphate pathway gene cluster of the lactose operon of Lactococcus lactis. J. Biol. Chem. 266 (1991) 7176–7181. [PMID: 1901863]
[EC 5.3.1.26 created 1999]
 
 
EC 5.3.2.3     
Accepted name: TDP-4-oxo-6-deoxy-α-D-glucose-3,4-oxoisomerase (dTDP-3-dehydro-6-deoxy-α-D-galactopyranose-forming)
Reaction: dTDP-4-dehydro-6-deoxy-α-D-glucopyranose = dTDP-3-dehydro-6-deoxy-α-D-galactopyranose
Other name(s): dTDP-6-deoxy-hex-4-ulose isomerase; TDP-6-deoxy-hex-4-ulose isomerase; FdtA
Systematic name: dTDP-4-dehydro-6-deoxy-α-D-glucopyranose:dTDP-3-dehydro-6-deoxy-α-D-galactopyranose isomerase
Comments: The enzyme is involved in the biosynthesis of dTDP-3-acetamido-3,6-dideoxy-α-D-galactose. Four moieties of α-D-rhamnose and two moities of 3-acetamido-3,6-dideoxy-α-D-galactose form the repeating unit of the glycan chain in the S-layer of the bacterium Aneurinibacillus thermoaerophilus.
References:
1.  Pfoestl, A., Hofinger, A., Kosma, P. and Messner, P. Biosynthesis of dTDP-3-acetamido-3,6-dideoxy-α-D-galactose in Aneurinibacillus thermoaerophilus L420-91T. J. Biol. Chem. 278 (2003) 26410–26417. [PMID: 12740380]
2.  Davis, M.L., Thoden, J.B. and Holden, H.M. The x-ray structure of dTDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase. J. Biol. Chem. 282 (2007) 19227–19236. [PMID: 17459872]
[EC 5.3.2.3 created 2011]
 
 
EC 5.4.2.2     
Accepted name: phosphoglucomutase (α-D-glucose-1,6-bisphosphate-dependent)
Reaction: α-D-glucose 1-phosphate = D-glucose 6-phosphate
Other name(s): glucose phosphomutase (ambiguous); phosphoglucose mutase (ambiguous)
Systematic name: α-D-glucose 1,6-phosphomutase
Comments: Maximum activity is only obtained in the presence of α-D-glucose 1,6-bisphosphate. This bisphosphate is an intermediate in the reaction, being formed by transfer of a phosphate residue from the enzyme to the substrate, but the dissociation of bisphosphate from the enzyme complex is much slower than the overall isomerization. The enzyme also catalyses (more slowly) the interconversion of 1-phosphate and 6-phosphate isomers of many other α-D-hexoses, and the interconversion of α-D-ribose 1-phosphate and 5-phosphate. cf. EC 5.4.2.5, phosphoglucomutase (glucose-cofactor).
References:
1.  Joshi, J.G. and Handler, P. Phosphoglucomutase. I. Purification and properties of phosphoglucomutase from Escherichia coli. J. Biol. Chem. 239 (1964) 2741–2751. [PMID: 14216423]
2.  Najjar, V.A. Phosphoglucomutase. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 6, Academic Press, New York, 1962, pp. 161–178.
3.  Ray, W.J. and Roscelli, G.A. A kinetic study of the phosphoglucomutase pathway. J. Biol. Chem. 239 (1964) 1228–1236. [PMID: 14165931]
4.  Ray, W.J., Jr. and Peck, E.J., Jr. Phosphomutases. In: Boyer, P.D. (Ed.), The Enzymes, 3rd edn, vol. 6, 1972, pp. 407–477.
5.  Sutherland, E.W., Cohn, M., Posternak, T. and Cori, C.F. The mechanism of the phosphoglucomutase reaction. J. Biol. Chem. 180 (1949) 1285–1295. [PMID: 18148026]
[EC 5.4.2.2 created 1961 as EC 2.7.5.1, transferred 1984 to EC 5.4.2.2]
 
 
EC 5.4.99.9     
Accepted name: UDP-galactopyranose mutase
Reaction: UDP-α-D-galactopyranose = UDP-α-D-galactofuranose
Other name(s): UGM; UDP-D-galactopyranose furanomutase
Systematic name: UDP-α-D-galactopyranose furanomutase
Comments: A flavoenzyme which generates UDP-α-D-glactofuranose required for cell wall formation in bacteria, fungi, and protozoa.
References:
1.  Trejo, A.G., Chittenden, G.J.F., Buchanan, J.G. and Baddiley, J. Uridine diphosphate α-D-galactofuranose, an intermediate in the biosynthesis of galactofuranosyl residues. Biochem. J. 117 (1970) 637–639. [PMID: 5419754]
2.  Karunan Partha, S., Bonderoff, S.A., van Straaten, K.E. and Sanders, D.A. Expression, purification and preliminary X-ray crystallographic analysis of UDP-galactopyranose mutase from Deinococcus radiodurans. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 65 (2009) 843–845. [PMID: 19652355]
3.  Dhatwalia, R., Singh, H., Oppenheimer, M., Karr, D.B., Nix, J.C., Sobrado, P. and Tanner, J.J. Crystal structures and small-angle x-ray scattering analysis of UDP-galactopyranose mutase from the pathogenic fungus Aspergillus fumigatus. J. Biol. Chem. 287 (2012) 9041–9051. [PMID: 22294687]
4.  van Straaten, K.E., Routier, F.H. and Sanders, D.A. Towards the crystal structure elucidation of eukaryotic UDP-galactopyranose mutase. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 68 (2012) 455–459. [PMID: 22505419]
[EC 5.4.99.9 created 1984, modified 2012]
 
 
EC 5.5.1.25     
Accepted name: 3,6-anhydro-L-galactonate cycloisomerase
Reaction: 3,6-anhydro-L-galactonate = 2-dehydro-3-deoxy-L-galactonate
Other name(s): 3,6-anhydro-α-L-galactonate lyase (ring-opening); 3,6-anhydro-α-L-galactonate cycloisomerase
Systematic name: 3,6-anhydro-L-galactonate lyase (ring-opening)
Comments: The enzyme, characterized from the marine bacteria Vibrio sp. EJY3 and Postechiella marina M091, is involved in a degradation pathway for 3,6-anhydro-α-L-galactopyranose, a major component of the polysaccharides of red macroalgae.
References:
1.  Yun, E.J., Lee, S., Kim, H.T., Pelton, J.G., Kim, S., Ko, H.J., Choi, I.G. and Kim, K.H. The novel catabolic pathway of 3,6-anhydro-L-galactose, the main component of red macroalgae, in a marine bacterium. Environ. Microbiol. 17 (2015) 1677–1688. [PMID: 25156229]
2.  Lee, S.B., Cho, S.J., Kim, J.A., Lee, S.Y., Kim, S.M. and Lim, H.S. Metabolic pathway of 3,6-anhydro-L-galactose in agar-degrading microorganisms. Biotechnol. Bioprocess Eng. 19 (2014) 866–878.
[EC 5.5.1.25 created 2014, modified 2015]
 
 
EC 7.5.2.2     
Accepted name: ABC-type oligosaccharide transporter
Reaction: ATP + H2O + oligosaccharide-[oligosaccharide-binding protein][side 1] = ADP + phosphate + oligosaccharide[side 2] + [oligosaccharide-binding protein][side 1]
Other name(s): oligosaccharide-transporting ATPase
Systematic name: ATP phosphohydrolase (ABC-type, oligosaccharide-importing)
Comments: An ATP-binding cassette (ABC) type transporter, characterized by the presence of two similar ATP-binding domains/proteins and two integral membrane domains/proteins. The enzyme, found in bacteria, interacts with an extracytoplasmic substrate binding protein and mediates the import of lactose, melibiose and raffinose.
References:
1.  Higgins, C.F. ABC transporters: from microorganisms to man. Annu. Rev. Cell Biol. 8 (1992) 67–113. [PMID: 1282354]
2.  Williams, S.G., Greenwood, J.A. and Jones, C.W. Molecular analysis of the lac operon encoding the binding-protein-dependent lactose transport system and β-galactosidase in Agrobacterium radiobacter. Mol. Microbiol. 6 (1992) 1755–1768. [PMID: 1630315]
3.  Tam, R. and Saier, M.H., Jr. Structural, functional, and evolutionary relationships among extracellular solute-binding receptors of bacteria. Microbiol. Rev. 57 (1993) 320–346. [PMID: 8336670]
4.  Kuan, G., Dassa, E., Saurin, N., Hofnung, M. and Saier, M.H., Jr. Phylogenetic analyses of the ATP-binding constituents of bacterial extracytoplasmic receptor-dependent ABC-type nutrient uptake permeases. Res. Microbiol. 146 (1995) 271–278. [PMID: 7569321]
5.  Saier, M.H., Jr. Molecular phylogeny as a basis for the classification of transport proteins from bacteria, archaea and eukarya. Adv. Microb. Physiol. 40 (1998) 81–136. [PMID: 9889977]
[EC 7.5.2.2 created 2000 as EC 3.6.3.18, transferred 2018 to EC 7.5.2.2]
 
 
EC 7.5.2.11     
Accepted name: ABC-type D-galactose transporter
Reaction: ATP + H2O + D-galactose-[galactose-binding protein][side 1] = ADP + phosphate + D-galactose[side 2] + [galactose-binding protein][side 1]
Other name(s): D-galactose transporting ATPase; D-galactose ABC transporter; mglBAC (gene names)
Systematic name: ATP phosphohydrolase (ABC-type, D-galactose-importing)
Comments: ATP-binding cassette (ABC) type transporter, characterized by the presence of two similar ATP-binding domains/proteins and two integral membrane domains/proteins. A bacterial enzyme, best characterized from Escherichia coli where it interacts with a periplasmic substrate binding protein and mediates the high affinity uptake of D-galactose and methyl-β-D-galactoside.
References:
1.  Hogg, R.W., Voelker, C. and Von Carlowitz, I. Nucleotide sequence and analysis of the mgl operon of Escherichia coli K12. Mol. Gen. Genet. 229 (1991) 453–459. [PMID: 1719366]
[EC 7.5.2.11 created 2019]