The Enzyme Database

Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (NC-IUBMB)

Proposed Changes to the Enzyme List

The entries below are proposed additions and amendments to the Enzyme Nomenclature list. They were prepared for the NC-IUBMB by Kristian Axelsen, Richard Cammack, Ron Caspi, Masaaki Kotera, Andrew McDonald, Gerry Moss, Dietmar Schomburg, Ida Schomburg and Keith Tipton. Comments and suggestions on these draft entries should be sent to Dr Andrew McDonald (Department of Biochemistry, Trinity College Dublin, Dublin 2, Ireland). The date on which an enzyme will be made official is appended after the EC number. To prevent confusion please do not quote new EC numbers until they are incorporated into the main list.

An asterisk before 'EC' indicates that this is an amendment to an existing enzyme rather than a new enzyme entry.


Contents

*EC 1.1.1.262 4-hydroxythreonine-4-phosphate dehydrogenase
*EC 1.1.3.2 L-lactate oxidase
EC 1.1.99.42 4-pyridoxic acid dehydrogenase
EC 1.2.1.100 5-formyl-3-hydroxy-2-methylpyridine 4-carboxylic acid 5-dehydrogenase
EC 1.3.1.114 3-dehydro-bile acid Δ4,6-reductase
EC 1.3.1.115 3-oxocholoyl-CoA 4-desaturase
EC 1.3.1.116 7β-hydroxy-3-oxochol-24-oyl-CoA 4-desaturase
EC 1.3.1.117 hydroxycinnamoyl-CoA reductase
EC 1.3.99.39 carotenoid φ-ring synthase
EC 1.3.99.40 carotenoid χ-ring synthase
EC 1.7.1.17 FMN-dependent NADH-azoreductase
EC 1.13.11.85 exo-cleaving rubber dioxygenase
EC 1.14.11.14 transferred
EC 1.14.11.19 transferred
EC 1.14.11.22 transferred
EC 1.14.11.23 transferred
EC 1.14.11.34 transferred
EC 1.14.11.50 transferred
EC 1.14.12.4 transferred
EC 1.14.12.5 transferred
EC 1.14.13.21 transferred
*EC 1.14.13.32 albendazole monooxygenase
EC 1.14.13.74 transferred
EC 1.14.13.78 transferred
EC 1.14.13.88 transferred
EC 1.14.13.136 transferred
EC 1.14.13.141 transferred
EC 1.14.13.143 transferred
EC 1.14.13.151 transferred
EC 1.14.13.152 transferred
EC 1.14.13.191 transferred
EC 1.14.13.194 transferred
EC 1.14.13.199 transferred
EC 1.14.13.205 transferred
EC 1.14.13.221 transferred
EC 1.14.13.240 2-polyprenylphenol 6-hydroxylase
EC 1.14.13.241 5-pyridoxate monooxygenase
EC 1.14.13.242 3-hydroxy-2-methylpyridine-5-carboxylate monooxygenase
*EC 1.14.14.56 1,8-cineole 2-exo-monooxygenase
EC 1.14.14.70 ent-sandaracopimaradiene 3-hydroxylase
EC 1.14.14.71 cucurbitadienol 11-hydroxylase
EC 1.14.14.72 drimenol monooxygenase
EC 1.14.14.73 albendazole monooxygenase (sulfoxide-forming)
EC 1.14.14.74 albendazole monooxygenase (hydroxylating)
EC 1.14.14.75 fenbendazole monooxygenase (4′-hydroxylating)
EC 1.14.14.76 ent-isokaurene C2/C3-hydroxylase
EC 1.14.14.77 phenylacetonitrile α-monooxygenase
EC 1.14.14.78 phylloquinone ω-hydroxylase
EC 1.14.14.79 docosahexaenoic acid ω-hydroxylase
EC 1.14.14.80 long-chain fatty acid ω-monooxygenase
EC 1.14.14.81 flavanoid 3′,5′-hydroxylase
EC 1.14.14.82 flavonoid 3′-monooxygenase
EC 1.14.14.83 geraniol 8-hydroxylase
EC 1.14.14.84 linalool 8-monooxygenase
EC 1.14.14.85 7-deoxyloganin 7-hydroxylase
EC 1.14.14.86 ent-kaurene monooxygenase
EC 1.14.14.87 2-hydroxyisoflavanone synthase
EC 1.14.15.27 β-dihydromenaquinone-9 ω-hydroxylase
EC 1.14.15.28 cholest-4-en-3-one 26-monooxygenase [(25R)-3-oxocholest-4-en-26-oate forming]
EC 1.14.15.29 cholest-4-en-3-one 26-monooxygenase [(25S)-3-oxocholest-4-en-26-oate forming]
EC 1.14.15.30 3-ketosteroid 9α-monooxygenase
*EC 1.14.19.9 tryptophan 7-halogenase
EC 1.14.19.54 1,2-dehydroreticuline synthase
EC 1.14.19.55 4-hydroxybenzoate brominase (decarboxylating)
EC 1.14.19.56 1H-pyrrole-2-carbonyl-[peptidyl-carrier protein] chlorinase
EC 1.14.19.57 1H-pyrrole-2-carbonyl-[peptidyl-carrier protein] brominase
EC 1.14.19.58 tryptophan 5-halogenase
EC 1.14.19.59 tryptophan 6-halogenase
EC 1.14.19.60 7-chloro-L-tryptophan 6-halogenase
EC 1.14.19.61 dihydrorhizobitoxine desaturase
EC 1.14.20.4 anthocyanidin synthase
EC 1.14.20.5 flavone synthase I
EC 1.14.20.6 flavonol synthase
EC 1.14.20.7 2-oxoglutarate/L-arginine monooxygenase/decarboxylase (succinate-forming)
EC 1.14.20.8 (–)-deoxypodophyllotoxin synthase
EC 1.14.20.9 L-tyrosine isonitrile desaturase
EC 1.14.20.10 L-tyrosine isonitrile desaturase/decarboxylase
EC 1.14.20.11 3-[(Z)-2-isocyanoethenyl]-1H-indole synthase
EC 1.14.20.12 3-[(E)-2-isocyanoethenyl]-1H-indole synthase
EC 1.14.20.13 6β-hydroxyhyoscyamine epoxidase
EC 1.14.99.60 3-demethoxyubiquinol 3-hydroxylase
*EC 1.18.6.1 nitrogenase
EC 1.18.6.2 vanadium-dependent nitrogenase
EC 2.1.1.348 mRNA m6A methyltransferase
*EC 2.3.1.74 chalcone synthase
*EC 2.3.1.97 glycylpeptide N-tetradecanoyltransferase
EC 2.3.1.269 apolipoprotein N-acyltransferase
EC 2.3.1.270 lyso-ornithine lipid O-acyltransferase
EC 2.3.1.271 L-glutamate-5-semialdehyde N-acetyltransferase
EC 2.3.1.272 2-acetylphloroglucinol acetyltransferase
*EC 2.4.1.53 poly(ribitol-phosphate) β-glucosyltransferase
*EC 2.4.1.70 poly(ribitol-phosphate) α-N-acetylglucosaminyltransferase
EC 2.4.1.95 deleted
*EC 2.4.1.101 α-1,3-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase
*EC 2.4.1.102 β-1,3-galactosyl-O-glycosyl-glycoprotein β-1,6-N-acetylglucosaminyltransferase
*EC 2.4.1.143 α-1,6-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase
*EC 2.4.1.144 β-1,4-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase
*EC 2.4.1.145 α-1,3-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase
*EC 2.4.1.146 β-1,3-galactosyl-O-glycosyl-glycoprotein β-1,3-N-acetylglucosaminyltransferase
*EC 2.4.1.155 α-1,6-mannosyl-glycoprotein 6-β-N-acetylglucosaminyltransferase
*EC 2.4.1.195 N-hydroxythioamide S-β-glucosyltransferase
*EC 2.4.1.201 α-1,6-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase
*EC 2.4.1.226 N-acetylgalactosaminyl-proteoglycan 3-β-glucuronosyltransferase
EC 2.4.1.353 sordaricin 6-deoxyaltrosyltransferase
EC 2.4.1.354 (R)-mandelonitrile β-glucosyltransferase
EC 2.4.1.355 poly(ribitol-phosphate) β-N-acetylglucosaminyltransferase
EC 2.4.1.356 glucosyl-dolichyl phosphate glucuronosyltransferase
EC 2.4.1.357 phlorizin synthase
EC 2.4.2.59 sulfide-dependent adenosine diphosphate thiazole synthase
EC 2.4.2.60 cysteine-dependent adenosine diphosphate thiazole synthase
EC 2.5.1.143 pyridinium-3,5-biscarboxylic acid mononucleotide synthase
EC 2.5.1.144 S-sulfo-L-cysteine synthase (O-acetyl-L-serine-dependent)
EC 2.5.1.145 phosphatidylglycerol—prolipoprotein diacylglyceryl transferase
EC 2.5.1.146 3-geranyl-3-[(Z)-2-isocyanoethenyl]indole synthase
*EC 2.6.1.92 UDP-4-amino-4,6-dideoxy-N-acetyl-β-L-altrosamine transaminase
*EC 2.7.1.209 L-erythrulose 1-kinase
EC 2.7.7.100 SAMP-activating enzyme
*EC 2.8.1.8 lipoyl synthase
EC 2.8 Transferring sulfur-containing groups
EC 2.8.5 Thiosulfotransferases
EC 2.8.5.1 S-sulfo-L-cysteine synthase (3-phospho-L-serine-dependent)
EC 3.1.6.20 S-sulfosulfanyl-L-cysteine sulfohydrolase
*EC 3.2.1.106 mannosyl-oligosaccharide glucosidase
*EC 3.2.1.114 mannosyl-oligosaccharide 1,3-1,6-α-mannosidase
*EC 3.2.1.170 mannosylglycerate hydrolase
EC 3.2.1.207 mannosyl-oligosaccharide α-1,3-glucosidase
*EC 3.3.1.2 S-adenosyl-L-methionine hydrolase (L-homoserine-forming)
EC 3.5.1.128 deaminated glutathione amidase
*EC 3.7.1.4 phloretin hydrolase
EC 3.13.1.8 S-adenosyl-L-methionine hydrolase (adenosine-forming)
EC 4.1.1.110 bisphosphomevalonate decarboxylase
EC 4.1.1.111 siroheme decarboxylase
EC 4.4.1.37 pyridinium-3,5-bisthiocarboxylic acid mononucleotide synthase
EC 5.3.3.22 lutein isomerase
EC 5.5.1.31 hapalindole H synthase
EC 5.5.1.32 12-epi-hapalindole U synthase
EC 5.5.1.33 12-epi-fischerindole U synthase
EC 6.2.1.53 L-proline—[L-prolyl-carrier protein] ligase
EC 6.2.1.54 D-alanine—[D-alanyl-carrier protein] ligase
EC 6.2.1.55 E1 SAMP-activating enzyme


*EC 1.1.1.262
Accepted name: 4-hydroxythreonine-4-phosphate dehydrogenase
Reaction: 4-phosphooxy-L-threonine + NAD+ = 3-amino-2-oxopropyl phosphate + CO2 + NADH + H+
For diagram of pyridoxal biosynthesis, click here
Other name(s): NAD+-dependent threonine 4-phosphate dehydrogenase; L-threonine 4-phosphate dehydrogenase; 4-(phosphohydroxy)-L-threonine dehydrogenase; PdxA; 4-(phosphonooxy)-L-threonine:NAD+ oxidoreductase; 4-phosphooxy-L-threonine:NAD+ oxidoreductase
Systematic name: 4-phosphooxy-L-threonine:NAD+ 3-oxidoreductase (decarboxylating)
Comments: The enzyme is part of the biosynthesis pathway of the coenzyme pyridoxal 5′-phosphate found in anaerobic bacteria.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, CAS registry number: 230310-36-8
References:
1.  Cane, D.E., Hsiung, Y., Cornish, J.A., Robinson, J.K and Spenser, I.D. Biosynthesis of vitamine B6: The oxidation of L-threonine 4-phosphate by PdxA. J. Am. Chem. Soc. 120 (1998) 1936–1937.
2.  Laber, B., Maurer, W., Scharf, S., Stepusin, K. and Schmidt, F.S. Vitamin B6 biosynthesis: formation of pyridoxine 5′-phosphate from 4-(phosphohydroxy)-L-threonine and 1-deoxy-D-xylulose-5-phosphate by PdxA and PdxJ protein. FEBS Lett. 449 (1999) 45–48. [DOI] [PMID: 10225425]
3.  Sivaraman, J., Li, Y., Banks, J., Cane, D.E., Matte, A. and Cygler, M. Crystal structure of Escherichia coli PdxA, an enzyme involved in the pyridoxal phosphate biosynthesis pathway. J. Biol. Chem. 278 (2003) 43682–43690. [DOI] [PMID: 12896974]
4.  Banks, J. and Cane, D.E. Biosynthesis of vitamin B6: direct identification of the product of the PdxA-catalyzed oxidation of 4-hydroxy-l-threonine-4-phosphate using electrospray ionization mass spectrometry. Bioorg. Med. Chem. Lett. 14 (2004) 1633–1636. [PMID: 15026039]
[EC 1.1.1.262 created 2000, modified 2006, modified 2018]
 
 
*EC 1.1.3.2
Accepted name: L-lactate oxidase
Reaction: (S)-lactate + O2 = pyruvate + H2O2
Other name(s): lctO (gene name); LOX
Systematic name: (S)-lactate:oxygen 2-oxidoreductase
Comments: Contains flavin mononucleotide (FMN). The best characterized enzyme is that from the bacterium Aerococcus viridans. The enzyme is widely used in biosensors to measure the lactate concentration in blood and other tissues.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Duncan, J.D., Wallis, J.O. and Azari, M.R. Purification and properties of Aerococcus viridans lactate oxidase. Biochem. Biophys. Res. Commun. 164 (1989) 919–926. [DOI] [PMID: 2818595]
2.  Maeda-Yorita, K., Aki, K., Sagai, H., Misaki, H. and Massey, V. L-lactate oxidase and L-lactate monooxygenase: mechanistic variations on a common structural theme. Biochimie 77 (1995) 631–642. [DOI] [PMID: 8589073]
3.  Gibello, A., Collins, M.D., Dominguez, L., Fernandez-Garayzabal, J.F. and Richardson, P.T. Cloning and analysis of the L-lactate utilization genes from Streptococcus iniae. Appl. Environ. Microbiol. 65 (1999) 4346–4350. [PMID: 10508058]
4.  Umena, Y., Yorita, K., Matsuoka, T., Kita, A., Fukui, K. and Morimoto, Y. The crystal structure of L-lactate oxidase from Aerococcus viridans at 2.1 Å resolution reveals the mechanism of strict substrate recognition. Biochem. Biophys. Res. Commun. 350 (2006) 249–256. [DOI] [PMID: 17007814]
5.  Furuichi, M., Suzuki, N., Dhakshnamoorhty, B., Minagawa, H., Yamagishi, R., Watanabe, Y., Goto, Y., Kaneko, H., Yoshida, Y., Yagi, H., Waga, I., Kumar, P.K. and Mizuno, H. X-ray structures of Aerococcus viridans lactate oxidase and its complex with D-lactate at pH 4.5 show an α-hydroxyacid oxidation mechanism. J. Mol. Biol. 378 (2008) 436–446. [DOI] [PMID: 18367206]
6.  Stoisser, T., Brunsteiner, M., Wilson, D.K. and Nidetzky, B. Conformational flexibility related to enzyme activity: evidence for a dynamic active-site gatekeeper function of Tyr215 in Aerococcus viridans lactate oxidase. Sci Rep 6:27892 (2016). [DOI] [PMID: 27302031]
[EC 1.1.3.2 created 1961, transferred 1972 to EC 1.13.12.4, reinstated 2018]
 
 
EC 1.1.99.42
Accepted name: 4-pyridoxic acid dehydrogenase
Reaction: 4-pyridoxate + acceptor = 5-formyl-3-hydroxy-2-methylpyridine-4-carboxylate + reduced acceptor
For diagram of pyridoxal catabolism, click here
Glossary: 4-pyridoxate = 3-hydroxy-5-(hydroxymethyl)-2-methylpyridine-4-carboxylate
dichloroindophenol = DCPIP = 2,6-dichloro-4-[(4-hydroxyphenyl)imino]cyclohexa-2,5-dien-1-one
Other name(s): mlr6792 (locus name)
Systematic name: 4-pyridoxate:acceptor 5-oxidoreductase
Comments: The enzyme, characterized from the bacteria Pseudomonas sp. MA-1 and Mesorhizobium loti, participates in the degradation of pyridoxine (vitamin B6). It is membrane bound and contains FAD. The enzyme has been assayed in vitro in the presence of the artificial electron acceptor dichloroindophenol (DCPIP).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Yagi, T., Kishore, G.M. and Snell, E.E. The bacterial oxidation of vitamin B6. 4-Pyridoxic acid dehydrogenase: a membrane-bound enzyme from Pseudomonas MA-1. J. Biol. Chem 258 (1983) 9419–9425. [PMID: 6348042]
2.  Ge, F., Yokochi, N., Yoshikane, Y., Ohnishi, K. and Yagi, T. Gene identification and characterization of the pyridoxine degradative enzyme 4-pyridoxic acid dehydrogenase from the nitrogen-fixing symbiotic bacterium Mesorhizobium loti MAFF303099. J. Biochem. 143 (2008) 603–609. [DOI] [PMID: 18216065]
[EC 1.1.99.42 created 2018]
 
 
EC 1.2.1.100
Accepted name: 5-formyl-3-hydroxy-2-methylpyridine 4-carboxylic acid 5-dehydrogenase
Reaction: 5-formyl-3-hydroxy-2-methylpyridine-4-carboxylate + NAD+ + H2O = 3-hydroxy-2-methylpyridine-4,5-dicarboxylate + NADH + H+
For diagram of pyridoxal catabolism, click here
Other name(s): mlr6793 (locus name)
Systematic name: 5-formyl-3-hydroxy-2-methylpyridine-4-carboxylate:NAD+ 5-oxidoreductase
Comments: The enzyme, characterized from the bacteria Pseudomonas sp. MA-1 and Mesorhizobium loti, participates in the degradation of pyridoxine (vitamin B6).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Lee, Y.C., Nelson, M.J. and Snell, E.E. Enzymes of vitamin B6 degradation. Purification and properties of isopyridoxal dehydrogenase and 5-formyl-3-hydroxy-2-methylpyridine-4-carboxylic-acid dehydrogenase. J. Biol. Chem 261 (1986) 15106–15111. [PMID: 3533936]
2.  Yokochi, N., Yoshikane, Y., Matsumoto, S., Fujisawa, M., Ohnishi, K. and Yagi, T. Gene identification and characterization of 5-formyl-3-hydroxy-2-methylpyridine 4-carboxylic acid 5-dehydrogenase, an NAD+-dependent dismutase. J. Biochem. 145 (2009) 493–503. [DOI] [PMID: 19218190]
3.  Mugo, A.N., Kobayashi, J., Mikami, B., Yoshikane, Y., Yagi, T. and Ohnishi, K. Crystal structure of 5-formyl-3-hydroxy-2-methylpyridine 4-carboxylic acid 5-dehydrogenase, an NAD(+)-dependent dismutase from Mesorhizobium loti. Biochem. Biophys. Res. Commun. 456 (2015) 35–40. [DOI] [PMID: 25446130]
[EC 1.2.1.100 created 2018]
 
 
EC 1.3.1.114
Accepted name: 3-dehydro-bile acid Δ4,6-reductase
Reaction: (1) 3-oxocholan-24-oyl-CoA + NAD+ = 3-oxochol-4-en-24-oyl-CoA + NADH + H+
(2) 3-oxochol-4-en-24-oyl-CoA + NAD+ = 3-oxochol-4,6-dien-24-oyl-CoA + NADH + H+
(3) 12α-hydroxy-3-oxocholan-24-oyl-CoA + NAD+ = 12α-hydroxy-3-oxochol-4-en-24-oyl-CoA + NADH + H+
(4) 12α-hydroxy-3-oxochol-4-en-24-oyl-CoA + NAD+ = 12α-hydroxy-3-oxochol-4,6-dien-24-oyl-CoA + NADH + H+
Other name(s): baiN (gene name)
Systematic name: 3-oxocholan-24-oyl-CoA Δ4,6-oxidoreductase
Comments: Contains flavin. The enzyme, characterized from the bacterium Clostridium scindens, participates in the bile acid 7α-dehydroxylation pathway. The enzyme catalyses two subsequent reductions of the double bonds within the bile acid A/B rings, following 7α-dehydration.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Harris, S.C., Devendran, S., Alves, J.MP., Mythen, S.M., Hylemon, P.B. and Ridlon, J.M. Identification of a gene encoding a flavoprotein involved in bile acid metabolism by the human gut bacterium Clostridium scindens ATCC 35704. Biochim. Biophys. Acta 1863 (2018) 276–283. [DOI] [PMID: 29217478]
[EC 1.3.1.114 created 2018]
 
 
EC 1.3.1.115
Accepted name: 3-oxocholoyl-CoA 4-desaturase
Reaction: (1) 7α,12α-dihydroxy-3-oxochol-24-oyl-CoA + NAD+ = 7α,12α-dihydroxy-3-oxochol-4-en-24-oyl-CoA + NADH + H+
(2) 7α-hydroxy-3-oxochol-24-oyl-CoA + NAD+ = 7α-hydroxy-3-oxochol-4-en-24-oyl-CoA + NADH + H+
Glossary: 7α,12α-dihydroxy-3-oxochol-24-oyl-CoA = 3-oxocholoyl-CoA
7α-hydroxy-3-oxochol-24-oyl-CoA = 3-oxochenodeoxycholoyl-CoA
Other name(s): baiCD (gene name); 3-oxo-choloyl-CoA dehydrogenase
Systematic name: 3-oxocholoyl-CoA Δ4-oxidoreductase
Comments: Contains flavin. The enzyme, characterized from the bacterium Clostridium scindens, participates in the bile acid 7α-dehydroxylation pathway. The enzyme catalyses the stereo-specific oxidation of its substrates and has no activity with the 7β anomers. cf. EC 1.3.1.116, 7β-hydroxy-3-oxochol-24-oyl-CoA 4-desaturase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Kang, D.J., Ridlon, J.M., Moore, D.R., 2nd, Barnes, S. and Hylemon, P.B. Clostridium scindens baiCD and baiH genes encode stereo-specific 7α/7β-hydroxy-3-oxo-Δ4-cholenoic acid oxidoreductases. Biochim. Biophys. Acta 1781 (2008) 16–25. [PMID: 18047844]
[EC 1.3.1.115 created 2018]
 
 
EC 1.3.1.116
Accepted name: 7β-hydroxy-3-oxochol-24-oyl-CoA 4-desaturase
Reaction: 7β-hydroxy-3-oxochol-24-oyl-CoA + NAD+ = 7β-hydroxy-3-oxochol-4-en-24-oyl-CoA + NADH + H+
Other name(s): baiH (gene name)
Systematic name: 7β-hydroxy-3-oxochol-24-oyl-CoA Δ4-oxidoreductase
Comments: Contains FAD and FMN. The enzyme, characterized from the bacterium Clostridium scindens, participates in the bile acid 7α-dehydroxylation pathway. The enzyme catalyses the stereo-specific oxidation of its substrate and has no activity with the 7α anomer. cf. EC 1.3.1.115, 3-oxocholoyl-CoA 4-desaturase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Baron, S.F. and Hylemon, P.B. Expression of the bile acid-inducible NADH:flavin oxidoreductase gene of Eubacterium sp. VPI 12708 in Escherichia coli. Biochim. Biophys. Acta 1249 (1995) 145–154. [PMID: 7599167]
2.  Franklund, C.V., Baron, S.F. and Hylemon, P.B. Characterization of the baiH gene encoding a bile acid-inducible NADH:flavin oxidoreductase from Eubacterium sp. strain VPI 12708. J. Bacteriol. 175 (1993) 3002–3012. [PMID: 8491719]
3.  Kang, D.J., Ridlon, J.M., Moore, D.R., 2nd, Barnes, S. and Hylemon, P.B. Clostridium scindens baiCD and baiH genes encode stereo-specific 7α/7β-hydroxy-3-oxo-Δ4-cholenoic acid oxidoreductases. Biochim. Biophys. Acta 1781 (2008) 16–25. [PMID: 18047844]
[EC 1.3.1.116 created 2018]
 
 
EC 1.3.1.117
Accepted name: hydroxycinnamoyl-CoA reductase
Reaction: (1) dihydro-4-coumaroyl-CoA + NADP+ = trans-4-coumaroyl-CoA + NADPH + H+
(2) dihydroferuloyl-CoA + NADP+ = trans-feruloyl-CoA + NADPH + H+
For diagram of phloretin biosynthesis, click here
Glossary: trans-4-coumaroyl-CoA = (E)-3-(4-hydroxyphenyl)prop-2-enoyl-CoA
trans-feruloyl-CoA = (E)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoyl-CoA
dihydro-4-coumaroyl-CoA = 3-(4-hydroxyphenyl)propanoyl-CoA
dihydroferuloyl-CoA = 3-(4-hydroxy-3-methoxyphenyl)propanoyl-CoA
Other name(s): MdHCDBR; hydroxycinnamoyl-CoA double bond reductase
Systematic name: dihydro-4-coumaroyl-CoA:NADP+ 2,3-oxidoreductase
Comments: Isolated from Malus X domestica (apple). Involved in dihydrochalcone biosynthesis.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Ibdah, M., Berim, A., Martens, S., Valderrama, A.L.H., Palmieri, L., Lewinsohn, E. and Gang, D.R. Identification and cloning of an NADPH-dependant hydroxycinnamoyl-CoA double bond reductase involved in dihydrochalcone formation in Malus X domestica Borkh. Phytochemistry 107 (2014) 24-31. [DOI] [PMID: 25152451]
[EC 1.3.1.117 created 2018]
 
 
EC 1.3.99.39
Accepted name: carotenoid φ-ring synthase
Reaction: carotenoid β-end group + 2 acceptor = carotenoid φ-end group + 2 reduced acceptor
For diagram of aromatic carotenoid biosynthesis, click here
Glossary: chlorobactene = φ,ψ-carotene
β-isorenieratene = φ,β-carotene
isorenieratene = φ,φ-carotene
Other name(s): crtU (gene name)
Systematic name: carotenoid β-ring:acceptor oxidoreductase/methyltranferase (φ-ring forming)
Comments: The enzyme, found in green sulfur bacteria, some cyanobacteria and some actinobacteria, introduces additional double bonds to the carotenoid β-end group, leading to aromatization of the ionone ring. As a result, one of the methyl groups at C-1 is transferred to position C-2. It is involved in the biosynthesis of carotenoids with φ-type aromatic end groups such as chlorobactene, β-isorenieratene, and isorenieratene.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Moshier, S.E. and Chapman, D.J. Biosynthetic studies on aromatic carotenoids. Biosynthesis of chlorobactene. Biochem. J. 136 (1973) 395–404. [PMID: 4774401]
2.  Krugel, H., Krubasik, P., Weber, K., Saluz, H.P. and Sandmann, G. Functional analysis of genes from Streptomyces griseus involved in the synthesis of isorenieratene, a carotenoid with aromatic end groups, revealed a novel type of carotenoid desaturase. Biochim. Biophys. Acta 1439 (1999) 57–64. [PMID: 10395965]
3.  Frigaard, N.U., Maresca, J.A., Yunker, C.E., Jones, A.D. and Bryant, D.A. Genetic manipulation of carotenoid biosynthesis in the green sulfur bacterium Chlorobium tepidum. J. Bacteriol. 186 (2004) 5210–5220. [PMID: 15292122]
[EC 1.3.99.39 created 2018]
 
 
EC 1.3.99.40
Accepted name: carotenoid χ-ring synthase
Reaction: carotenoid β-end group + 2 acceptor = carotenoid χ-end group + 2 reduced acceptor
For diagram of aromatic carotenoid biosynthesis, click here
Glossary: okenone = 1′-methoxy-1′,2′-dihydro-χ,ψ-caroten-4′-one
renierapurpurin = χ,χ-carotene
synechoxanthin = χ,χ-caroten-18,18′-dioate
Other name(s): crtU (gene name); cruE (gene name)
Systematic name: carotenoid β-ring:acceptor oxidoreductase/methyltranferase (χ-ring forming)
Comments: The enzyme, found in purple sulfur bacteria (Chromatiaceae) and some cyanobacteria, is involved in the biosynthesis of carotenoids that contain χ-type end groups, such as okenone, renierapurpurin, and synechoxanthin.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Graham, J.E. and Bryant, D.A. The Biosynthetic pathway for synechoxanthin, an aromatic carotenoid synthesized by the euryhaline, unicellular cyanobacterium Synechococcus sp. strain PCC 7002. J. Bacteriol. 190 (2008) 7966–7974. [DOI] [PMID: 18849428]
2.  Vogl, K. and Bryant, D.A. Biosynthesis of the biomarker okenone: χ-ring formation. Geobiology 10 (2012) 205–215. [DOI] [PMID: 22070388]
[EC 1.3.99.40 created 2018]
 
 
EC 1.7.1.17
Accepted name: FMN-dependent NADH-azoreductase
Reaction: anthranilate + N,N-dimethyl-1,4-phenylenediamine + 2 NAD+ = 2-(4-dimethylaminophenyl)diazenylbenzoate + 2 NADH + 2 H+
Glossary: 2-(4-dimethylaminophenyl)diazenylbenzoate = methyl red
Other name(s): azoR (gene name); NADH-azoreductase
Systematic name: N,N-dimethyl-1,4-phenylenediamine, anthranilate:NAD+ oxidoreductase
Comments: Requires FMN. The enzyme catalyses the reductive cleavage of an azo bond in aromatic azo compounds to form the corresponding amines. Does not accept NADPH. cf. EC 1.7.1.6, azobenzene reductase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Nakanishi, M., Yatome, C., Ishida, N. and Kitade, Y. Putative ACP phosphodiesterase gene (acpD) encodes an azoreductase. J. Biol. Chem. 276 (2001) 46394–46399. [DOI] [PMID: 11583992]
2.  Ito, K., Nakanishi, M., Lee, W.C., Sasaki, H., Zenno, S., Saigo, K., Kitade, Y. and Tanokura, M. Crystallization and preliminary X-ray analysis of AzoR (azoreductase) from Escherichia coli. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 61 (2005) 399–402. [DOI] [PMID: 16511052]
3.  Ito, K., Nakanishi, M., Lee, W.C., Zhi, Y., Sasaki, H., Zenno, S., Saigo, K., Kitade, Y. and Tanokura, M. Expansion of substrate specificity and catalytic mechanism of azoreductase by X-ray crystallography and site-directed mutagenesis. J. Biol. Chem. 283 (2008) 13889–13896. [DOI] [PMID: 18337254]
4.  Mercier, C., Chalansonnet, V., Orenga, S. and Gilbert, C. Characteristics of major Escherichia coli reductases involved in aerobic nitro and azo reduction. J. Appl. Microbiol. 115 (2013) 1012–1022. [DOI] [PMID: 23795903]
[EC 1.7.1.17 created 2018]
 
 
EC 1.13.11.85
Accepted name: exo-cleaving rubber dioxygenase
Reaction: cis-1,4-polyisoprene + n O2 = n (4Z,8Z)-4,8-dimethyl-12-oxotrideca-4,8-dienal
Other name(s): roxA (gene name); heme-dependent rubber oxygenase (ambiguous)
Systematic name: cis-1,4-polyisoprene:oxygen dioxygenase [(4Z,8Z)-4,8-dimethyl-12-oxotrideca-4,8-dienal-forming]
Comments: The enzyme, studied mainly from the bacterium Xanthomonas sp. 35Y, catalyses the cleavage of the double bonds in natural and synthetic rubber (cis-1,4-polyisoprene polymers), generating ends that contain ketone and aldehyde groups. The enzyme from Xanthomonas sp. 35Y contains two c-type cytochromes. It attacks the substrate from its end, producing a single product of 15 carbons.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Tsuchii, A. and Takeda, K. Rubber-degrading enzyme from a bacterial culture. Appl. Environ. Microbiol. 56 (1990) 269–274. [PMID: 16348100]
2.  Jendrossek, D. and Reinhardt, S. Sequence analysis of a gene product synthesized by Xanthomonas sp. during growth on natural rubber latex. FEMS Microbiol. Lett. 224 (2003) 61–65. [DOI] [PMID: 12855168]
3.  Braaz, R., Fischer, P. and Jendrossek, D. Novel type of heme-dependent oxygenase catalyzes oxidative cleavage of rubber (poly-cis-1,4-isoprene). Appl. Environ. Microbiol. 70 (2004) 7388–7395. [DOI] [PMID: 15574940]
4.  Braaz, R., Armbruster, W. and Jendrossek, D. Heme-dependent rubber oxygenase RoxA of Xanthomonas sp. cleaves the carbon backbone of poly(cis-1,4-Isoprene) by a dioxygenase mechanism. Appl. Environ. Microbiol. 71 (2005) 2473–2478. [DOI] [PMID: 15870336]
5.  Seidel, J., Schmitt, G., Hoffmann, M., Jendrossek, D. and Einsle, O. Structure of the processive rubber oxygenase RoxA from Xanthomonas sp. Proc. Natl Acad. Sci. USA 110 (2013) 13833–13838. [DOI] [PMID: 23922395]
6.  Birke, J. and Jendrossek, D. Rubber oxygenase and latex clearing protein cleave rubber to different products and use different cleavage mechanisms. Appl. Environ. Microbiol. 80 (2014) 5012–5020. [DOI] [PMID: 24907333]
[EC 1.13.11.85 created 2018]
 
 
EC 1.14.11.14
Transferred entry: 6β-hydroxyhyoscyamine epoxidase. Now EC 1.14.20.13, 6β-hydroxyhyoscyamine epoxidase
[EC 1.14.11.14 created 1992, deleted 2018]
 
 
EC 1.14.11.19
Transferred entry: anthocyanidin synthase. Now EC 1.14.20.4, anthocyanidin synthase
[EC 1.14.11.19 created 2001, modified 2017, deleted 2018]
 
 
EC 1.14.11.22
Transferred entry: flavone synthase. Now EC 1.14.20.5, flavone synthase
[EC 1.14.11.22 created 2004, deleted 2018]
 
 
EC 1.14.11.23
Transferred entry: flavonol synthase. Now EC 1.14.20.6, flavonol synthase
[EC 1.14.11.23 created 2004, deleted 2018]
 
 
EC 1.14.11.34
Transferred entry: 2-oxoglutarate/L-arginine monooxygenase/decarboxylase (succinate-forming). Now EC 1.14.20.7, 2-oxoglutarate/L-arginine monooxygenase/decarboxylase (succinate-forming)
[EC 1.14.11.34 created 2011, deleted 2018]
 
 
EC 1.14.11.50
Transferred entry: (–)-deoxypodophyllotoxin synthase. Now EC 1.14.20.8, (–)-deoxypodophyllotoxin synthase
[EC 1.14.11.50 created 2016, deleted 2018]
 
 
EC 1.14.12.4
Transferred entry: 3-hydroxy-2-methylpyridinecarboxylate dioxygenase. Now EC 1.14.13.242, 3-hydroxy-2-methylpyridinecarboxylate monooxygenase
[EC 1.14.12.4 created 1972, deleted 2018]
 
 
EC 1.14.12.5
Transferred entry: 5-pyridoxate dioxygenase. Now EC 1.14.13.241, 5-pyridoxate monooxygenase
[EC 1.14.12.5 created 1972, deleted 2018]
 
 
EC 1.14.13.21
Transferred entry: flavonoid 3′-monooxygenase. Now EC 1.14.14.82, flavonoid 3′-monooxygenase.
[EC 1.14.13.21 created 1983, deleted 2018]
 
 
*EC 1.14.13.32
Accepted name: albendazole monooxygenase
Reaction: albendazole + NADPH + H+ + O2 = albendazole S-oxide + NADP+ + H2O
For diagram of albendazole metabolism, click here
Glossary: albendazole = methyl [5-(propylsulfanyl)-1H-benzimidazol-2-yl]carbamate
Other name(s): albendazole oxidase (misleading); albendazole sulfoxidase (ambiguous); FMO3 (gene name); albendazole monooxygenase (flavin-containing)
Systematic name: albendazole,NADPH:oxygen oxidoreductase (sulfoxide-forming)
Comments: A microsomal flavin-containing monooxygenase. A similar conversion is also carried out by some microsomal cytochrome P-450 enzymes [EC 1.14.14.73, albendazole monooxygenase (sulfoxide-forming)]. It is estimated that cytochrome P-450s are responsible for 70% of the activity.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 101299-59-6
References:
1.  Fargetton, X., Galtier, P. and Delatour, P. Sulfoxidation of albendazole by a cytochrome P450-independent monooxygenase from rat liver microsomes. Vet. Res. Commun. 10 (1986) 317–324. [PMID: 3739217]
2.  Moroni, P., Buronfosse, T., Longin-Sauvageon, C., Delatour, P. and Benoit, E. Chiral sulfoxidation of albendazole by the flavin adenine dinucleotide-containing and cytochrome P450-dependent monooxygenases from rat liver microsomes. Drug Metab. Dispos. 23 (1995) 160–165. [PMID: 7736906]
3.  Rawden, H.C., Kokwaro, G.O., Ward, S.A. and Edwards, G. Relative contribution of cytochromes P-450 and flavin-containing monoxygenases to the metabolism of albendazole by human liver microsomes. Br. J. Clin. Pharmacol. 49 (2000) 313–322. [PMID: 10759686]
[EC 1.14.13.32 created 1989, modified 2018]
 
 
EC 1.14.13.74
Transferred entry: 7-deoxyloganin 7-hydroxylase. Now EC 1.14.14.85, 7-deoxyloganin 7-hydroxylase
[EC 1.14.13.74 created 2002, deleted 2018]
 
 
EC 1.14.13.78
Transferred entry: ent-kaurene oxidase. Now EC 1.14.14.86, ent-kaurene monooxygenase
[EC 1.14.13.78 created 2002, deleted 2018]
 
 
EC 1.14.13.88
Transferred entry: flavanoid 3,5-hydroxylase. Now EC 1.14.14.81, flavanoid 3,5-hydroxylase
[EC 1.14.13.88 created 2004, deleted 2018]
 
 
EC 1.14.13.136
Transferred entry: 2-hydroxyisoflavanone synthase. Now EC 1.14.14.87, 2-hydroxyisoflavanone synthase
[EC 1.14.13.136 created 2011, modified 2013, deleted 2018]
 
 
EC 1.14.13.141
Transferred entry: cholest-4-en-3-one 26-monooxygenase [(25S)-3-oxocholest-4-en-26-oate forming]. Now EC 1.14.15.29, cholest-4-en-3-one 26-monooxygenase [(25S)-3-oxocholest-4-en-26-oate forming]..
[EC 1.14.13.141 created 2012, modified 2016, deleted 2018]
 
 
EC 1.14.13.143
Transferred entry: ent-isokaurene C2-hydroxylase. Now EC 1.14.14.76 ent-isokaurene C2/C3-hydroxylase
[EC 1.14.13.143 created 2012, deleted 2018]
 
 
EC 1.14.13.151
Transferred entry: linalool 8-monooxygenase. Now EC 1.14.14.84, linalool 8-monooxygenase
[EC 1.14.13.151 created 1989 as EC 1.14.99.28, transferred 2012 to EC 1.14.13.151, deleted 2018]
 
 
EC 1.14.13.152
Transferred entry: geraniol 8-hydroxylase. Now EC 1.14.14.83, geraniol 8-hydroxylase
[EC 1.14.13.152 created 2012, deleted 2018]
 
 
EC 1.14.13.191
Transferred entry: ent-sandaracopimaradiene 3-hydroxylase. Now EC 1.14.14.70, ent-sandaracopimaradiene 3-hydroxylase
[EC 1.14.13.191 created 2014, deleted 2018]
 
 
EC 1.14.13.194
Transferred entry: phylloquinone ω-hydroxylase. Now EC 1.14.14.78, phylloquinone ω-hydroxylase
[EC 1.14.13.194 created 2014, deleted 2018]
 
 
EC 1.14.13.199
Transferred entry: docosahexaenoic acid ω-hydroxylase. Now EC 1.14.14.79, docosahexaenoic acid ω-hydroxylase
[EC 1.14.13.199 created 2014, deleted 2018]
 
 
EC 1.14.13.205
Transferred entry: long-chain fatty acid ω-monooxygenase. Now EC 1.14.14.80, long-chain fatty acid ω-monooxygenase
[EC 1.14.13.205 created 2015, deleted 2018]
 
 
EC 1.14.13.221
Transferred entry: cholest-4-en-3-one 26-monooxygenase [(25R)-3-oxocholest-4-en-26-oate forming]. Now EC 1.14.15.28, cholest-4-en-3-one 26-monooxygenase [(25R)-3-oxocholest-4-en-26-oate forming]
[EC 1.14.13.221 created 2016, deleted 2018]
 
 
EC 1.14.13.240
Accepted name: 2-polyprenylphenol 6-hydroxylase
Reaction: 2-(all-trans-polyprenyl)phenol + NADPH + H+ + O2 = 3-(all-trans-polyprenyl)benzene-1,2-diol + NADP+ + H2O
For diagram of ubiquinol biosynthesis, click here
Other name(s): ubiI (gene name); ubiM (gene name)
Systematic name: 2-(all-trans-polyprenyl)phenol,NADPH:oxygen oxidoreductase (6-hydroxylating)
Comments: Contains FAD. The enzyme from the bacterium Escherichia coli (UbiI) catalyses the first hydroxylation during the aerobic biosynthesis of ubiquinone. The enzyme from the bacterium Neisseria meningitidis (UbiM) can also catalyse the two additional hydroxylations that occur in the pathway (cf. EC 1.14.99.60, 3-demethoxyubiquinol 3-hydroxylase).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Young, I.G., McCann, L.M., Stroobant, P. and Gibson, F. Characterization and genetic analysis of mutant strains of Escherichia coli K-12 accumulating the biquinone precursors 2-octaprenyl-6-methoxy-1,4-benzoquinone and 2-octaprenyl-3-methyl-6-methoxy-1,4-benzoquinone. J. Bacteriol. 105 (1971) 769–778. [PMID: 4323297]
2.  Kwon, O., Kotsakis, A. and Meganathan, R. Ubiquinone (coenzyme Q) biosynthesis in Escherichia coli: identification of the ubiF gene. FEMS Microbiol. Lett. 186 (2000) 157–161. [PMID: 10802164]
[EC 1.14.13.240 created 2018]
 
 
EC 1.14.13.241
Accepted name: 5-pyridoxate monooxygenase
Reaction: 3-hydroxy-4-hydroxymethyl-2-methylpyridine-5-carboxylate + NADPH + H+ + O2 = 2-(acetamidomethylene)-3-(hydroxymethyl)succinate + NADP+
Glossary: 3-hydroxy-4-hydroxymethyl-2-methylpyridine-5-carboxylate = 5-pyridoxate
Other name(s): 5-pyridoxate,NADPH:oxygen oxidoreductase (decyclizing); 5-pyridoxate oxidase (misleading); 5-pyridoxate dioxygenase (incorrect)
Systematic name: 5-pyridoxate,NADPH:oxygen oxidoreductase (ring-opening)
Comments: Contains FAD. The enzyme, characterized from the bacterium Arthrobacter sp. Cr-7, participates in the degradation of pyridoxine (vitamin B6). Although the enzyme was initially thought to be a dioxygenase, oxygen-tracer experiments have suggested that it is a monooxygenase, incorporating only one oxygen atom from molecular oxygen into the product. The second oxygen atom originates from a water molecule, which is regenerated during the reaction and thus does not show up in the reaction equation.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, UM-BBD, CAS registry number: 37256-70-5
References:
1.  Sparrow, L.G., Ho, P.P.K., Sundaram, T.K., Zach, D., Nyns, E.J. and Snell, E.E. The bacterial oxidation of vitamin B6. VII. Purification, properties, and mechanism of action of an oxygenase which cleaves the 3-hydroxypyridine ring. J. Biol. Chem. 244 (1969) 2590–2600. [PMID: 4306031]
2.  Nelson, M.J. and Snell, E.E. Enzymes of vitamin B6 degradation. Purification and properties of 5-pyridoxic-acid oxygenase from Arthrobacter sp. J. Biol. Chem 261 (1986) 15115–15120. [PMID: 3771566]
3.  Chaiyen, P. Flavoenzymes catalyzing oxidative aromatic ring-cleavage reactions. Arch. Biochem. Biophys. 493 (2010) 62–70. [DOI] [PMID: 19728986]
[EC 1.14.13.241 created 2018 (EC 1.14.12.5 created 1972, incorporated 2018)]
 
 
EC 1.14.13.242
Accepted name: 3-hydroxy-2-methylpyridine-5-carboxylate monooxygenase
Reaction: 3-hydroxy-2-methylpyridine-5-carboxylate + NAD(P)H + H+ + O2 = 2-(acetamidomethylidene)succinate + NAD(P)+
For diagram of pyridoxal catabolism, click here
Other name(s): MHPCO; 3-hydroxy-2-methylpyridine-5-carboxylate,NAD(P)H:oxygen oxidoreductase (decyclizing); methylhydroxypyridinecarboxylate oxidase (misleading); 2-methyl-3-hydroxypyridine 5-carboxylic acid dioxygenase (incorrect); methylhydroxypyridine carboxylate dioxygenase (incorrect); 3-hydroxy-3-methylpyridinecarboxylate dioxygenase [incorrect]; 3-hydroxy-2-methylpyridinecarboxylate dioxygenase (incorrect)
Systematic name: 3-hydroxy-2-methylpyridine-5-carboxylate,NAD(P)H:oxygen oxidoreductase (ring-opening)
Comments: Contains FAD. The enzyme, characterized from the bacteria Pseudomonas sp. MA-1 and Mesorhizobium loti, participates in the degradation of pyridoxine (vitamin B6). Although the enzyme was initially thought to be a dioxygenase, oxygen-tracer experiments have shown that it is a monooxygenase, incorporating only one oxygen atom from molecular oxygen. The second oxygen atom that is incorporated into the product originates from a water molecule, which is regenerated during the reaction and thus does not show up in the reaction equation.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, UM-BBD, CAS registry number: 37256-69-2
References:
1.  Sparrow, L.G., Ho, P.P.K., Sundaram, T.K., Zach, D., Nyns, E.J. and Snell, E.E. The bacterial oxidation of vitamin B6. VII. Purification, properties, and mechanism of action of an oxygenase which cleaves the 3-hydroxypyridine ring. J. Biol. Chem. 244 (1969) 2590–2600. [PMID: 4306031]
2.  Chaiyen, P., Ballou, D.P. and Massey, V. Gene cloning, sequence analysis, and expression of 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase. Proc. Natl Acad. Sci. USA 94 (1997) 7233–7238. [PMID: 9207074]
3.  Oonanant, W., Sucharitakul, J., Yuvaniyama, J. and Chaiyen, P. Crystallization and preliminary X-ray crystallographic analysis of 2-methyl-3-hydroxypyridine-5-carboxylic acid (MHPC) oxygenase from Pseudomonas sp. MA-1. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 61 (2005) 312–314. [PMID: 16511028]
4.  Yuan, B., Yokochi, N., Yoshikane, Y., Ohnishi, K. and Yagi, T. Molecular cloning, identification and characterization of 2-methyl-3-hydroxypyridine-5-carboxylic-acid-dioxygenase-coding gene from the nitrogen-fixing symbiotic bacterium Mesorhizobium loti. J. Biosci. Bioeng. 102 (2006) 504–510. [PMID: 17270714]
5.  McCulloch, K.M., Mukherjee, T., Begley, T.P. and Ealick, S.E. Structure of the PLP degradative enzyme 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase from Mesorhizobium loti MAFF303099 and its mechanistic implications. Biochemistry 48 (2009) 4139–4149. [DOI] [PMID: 19317437]
6.  Tian, B., Tu, Y., Strid, A. and Eriksson, L.A. Hydroxylation and ring-opening mechanism of an unusual flavoprotein monooxygenase, 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase: a theoretical study. Chemistry 16 (2010) 2557–2566. [DOI] [PMID: 20066695]
7.  Tian, B., Strid, A. and Eriksson, L.A. Catalytic roles of active-site residues in 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase: an ONIOM/DFT study. J. Phys. Chem. B 115 (2011) 1918–1926. [DOI] [PMID: 21291225]
[EC 1.14.13.242 created 2018 (EC 1.14.12.4 created 1972, incorporated 2018)]
 
 
*EC 1.14.14.56
Accepted name: 1,8-cineole 2-exo-monooxygenase
Reaction: 1,8-cineole + [reduced NADPH—hemoprotein reductase] + O2 = 2-exo-hydroxy-1,8-cineole + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of 1,8-cineole catabolism, click here
Glossary: 1,8-cineole = 1,3,3-trimethyl-2-oxabicyclo[2.2.2]octane
2-exo-hydroxy-1,8-cineole = (1R,4S,6S)-1,3,3-trimethyl-2-oxabicyclo[2.2.2]octan-6-ol
Other name(s): CYP3A4
Systematic name: 1,8-cineole,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (2-exo-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein. The mammalian enzyme, expressed in liver microsomes, performs a variety of oxidation reactions of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. cf. EC 1.14.14.55, quinine 3-monooxygenase, EC 1.14.14.57, taurochenodeoxycholate 6-hydroxylase and EC 1.14.14.73, albendazole monooxygenase (sulfoxide-forming).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Miyazawa, M., Shindo, M. and Shimada, T. Oxidation of 1,8-cineole, the monoterpene cyclic ether originated from Eucalyptus polybractea, by cytochrome P450 3A enzymes in rat and human liver microsomes. Drug Metab. Dispos. 29 (2001) 200–205. [PMID: 11159812]
2.  Miyazawa, M. and Shindo, M. Biotransformation of 1,8-cineole by human liver microsomes. Nat. Prod. Lett. 15 (2001) 49–53. [DOI] [PMID: 11547423]
3.  Miyazawa, M., Shindo, M. and Shimada, T. Roles of cytochrome P450 3A enzymes in the 2-hydroxylation of 1,4-cineole, a monoterpene cyclic ether, by rat and human liver microsomes. Xenobiotica 31 (2001) 713–723. [DOI] [PMID: 11695850]
[EC 1.14.14.56 created 2012 as EC 1.14.13.157, transferred 2017 to EC 1.14.14.56, modified 2018]
 
 
EC 1.14.14.70
Accepted name: ent-sandaracopimaradiene 3-hydroxylase
Reaction: ent-sandaracopimaradiene + [reduced NADPH—hemoprotein reductase] + O2 = ent-sandaracopimaradien-3β-ol + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of oryzalexins biosynthesis, click here
Glossary: ent-sandaracopimaradiene = ent-13α-pimara-8(14),15-diene = (4aR,4bR,7S,10aR)-7-ethenyl-1,1,4a,7-tetramethyl-1,2,3,4,4a,4b,5,6,7,9,10,10a-dodecahydrophenanthrene
Other name(s): CYP701A; OsKOL4
Systematic name: ent-sandaracopimaradiene,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (ent-sandaracopimaradien-3β-ol forming)
Comments: A cytochrome P-450 (heme-thiolate) protein isolated from Oryza sativa (rice). Participates in the pathway for the biosynthesis of oryzalexins, a group of related phytoalexins produced by rice. Can also use 9β-pimara-7,15-diene as substrate (cf. EC 1.14.14.68, syn-pimaradiene 3-monooxygenase).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Wang, Q., Hillwig, M.L., Wu, Y. and Peters, R.J. CYP701A8: a rice ent-kaurene oxidase paralog diverted to more specialized diterpenoid metabolism. Plant Physiol. 158 (2012) 1418–1425. [DOI] [PMID: 22247270]
2.  Wu, Y., Wang, Q., Hillwig, M.L. and Peters, R.J. Picking sides: distinct roles for CYP76M6 and CYP76M8 in rice oryzalexin biosynthesis. Biochem. J. 454 (2013) 209–216. [DOI] [PMID: 23795884]
[EC 1.14.14.70 created 2014 as EC 1.14.13.191, transferred 2018 to EC 1.14.14.70]
 
 
EC 1.14.14.71
Accepted name: cucurbitadienol 11-hydroxylase
Reaction: cucurbitadienol + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = 11-oxocucurbitadienol + 2 [oxidized NADPH—hemoprotein reductase] + 3 H2O (overall reaction)
(1a) cucurbitadienol + [reduced NADPH—hemoprotein reductase] + O2 = 11-hydroxycucurbitadienol + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) 11-hydroxycucurbitadienol + [reduced NADPH—hemoprotein reductase] + O2 = 11-oxocucurbitadienol + [oxidized NADPH—hemoprotein reductase] + 2 H2O
For diagram of cucurbitadienol metabolites, click here
Glossary: 11-oxocucurbitadienol = 3β-hydroxycucurbita-7,24-dien-11-one
Other name(s): CYP87D18
Systematic name: cucurbitadienol,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (11-oxocucurbitadienol forming)
Comments: Isolated from the plant Siraitia grosvenorii (monk fruit).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Zhang, J., Dai, L., Yang, J., Liu, C., Men, Y., Zeng, Y., Cai, Y., Zhu, Y. and Sun, Y. Oxidation of cucurbitadienol catalyzed by CYP87D18 in the biosynthesis of mogrosides from Siraitia grosvenorii. Plant Cell Physiol 57 (2016) 1000–1007. [DOI] [PMID: 26903528]
[EC 1.14.14.71 created 2018]
 
 
EC 1.14.14.72
Accepted name: drimenol monooxygenase
Reaction: drimenol + [reduced NADPH—hemoprotein reductase] + O2 = drimendiol + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of drimenol metabolites, click here
Glossary: drimendiol = drim-7-ene-11,12-diol
Other name(s): PhDOX1
Systematic name: drimenol,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (drimendiol forming)
Comments: A cytochrome P-450 (heme-thiolate) protein isolated from the plant Persicaria hydropiper (water pepper).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Henquet, M.GL., Prota, N., van der Hooft, J.JJ., Varbanova-Herde, M., Hulzink, R.JM., de Vos, M., Prins, M., de Both, M.TJ., Franssen, M.CR., Bouwmeester, H. and Jongsma, M. Identification of a drimenol synthase and drimenol oxidase from Persicaria hydropiper, involved in the biosynthesis of insect deterrent drimanes. Plant J. 90 (2017) 1052–1063. [DOI] [PMID: 28258968]
[EC 1.14.14.72 created 2018]
 
 
EC 1.14.14.73
Accepted name: albendazole monooxygenase (sulfoxide-forming)
Reaction: (1) albendazole + [reduced NADPH—hemoprotein reductase] + O2 = albendazole S-oxide + [oxidized NADPH—hemoprotein reductase] + H2O
(2) fenbendazole + [reduced NADPH—hemoprotein reductase] + O2 = fenbendazole S-oxide + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of albendazole metabolism, click here
Glossary: albendazole = methyl [5-(propylsulfanyl)-1H-benzimidazol-2-yl]carbamate
fenbendazole = methyl [5-(phenylsulfanyl)-1H-benzimidazol-2-yl]carbamate
Other name(s): albendazole sulfoxidase (ambiguous); albendazole hydroxylase (ambiguous); CYP3A4 (gene name); CYP2J2 (gene name); CYP1A2 (gene name)
Systematic name: albendazole,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (sulfoxide-forming)
Comments: This is one of the activities carried out by some microsomal cytochrome P-450 monooxygenases. A similar conversion is also carried out by a different microsomal enzyme (EC 1.14.13.32, albendazole monooxygenase (flavin-containing)), but it is estimated that cytochrome P-450s are responsible for 70% of the activity.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, CAS registry number: 9059-22-7
References:
1.  Moroni, P., Buronfosse, T., Longin-Sauvageon, C., Delatour, P. and Benoit, E. Chiral sulfoxidation of albendazole by the flavin adenine dinucleotide-containing and cytochrome P450-dependent monooxygenases from rat liver microsomes. Drug Metab. Dispos. 23 (1995) 160–165. [PMID: 7736906]
2.  Rawden, H.C., Kokwaro, G.O., Ward, S.A. and Edwards, G. Relative contribution of cytochromes P-450 and flavin-containing monoxygenases to the metabolism of albendazole by human liver microsomes. Br. J. Clin. Pharmacol. 49 (2000) 313–322. [PMID: 10759686]
3.  Asteinza, J., Camacho-Carranza, R., Reyes-Reyes, R.E., Dorado-Gonzalez, V., V. and Espinosa-Aguirre, J.J. Induction of cytochrome P450 enzymes by albendazole treatment in the rat. Environ Toxicol Pharmacol 9 (2000) 31–37. [PMID: 11137466]
4.  Lee, C.A., Neul, D., Clouser-Roche, A., Dalvie, D., Wester, M.R., Jiang, Y., Jones, J.P., 3rd, Freiwald, S., Zientek, M. and Totah, R.A. Identification of novel substrates for human cytochrome P450 2J2. Drug Metab. Dispos. 38 (2010) 347–356. [DOI] [PMID: 19923256]
5.  Wu, Z., Lee, D., Joo, J., Shin, J.H., Kang, W., Oh, S., Lee, D.Y., Lee, S.J., Yea, S.S., Lee, H.S., Lee, T. and Liu, K.H. CYP2J2 and CYP2C19 are the major enzymes responsible for metabolism of albendazole and fenbendazole in human liver microsomes and recombinant P450 assay systems. Antimicrob. Agents Chemother. 57 (2013) 5448–5456. [DOI] [PMID: 23959307]
[EC 1.14.14.73 created 2018]
 
 
EC 1.14.14.74
Accepted name: albendazole monooxygenase (hydroxylating)
Reaction: albendazole + [reduced NADPH—hemoprotein reductase] + O2 = hydroxyalbendazole + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of albendazole metabolism, click here
Glossary: albendazole = methyl [5-(propylsulfanyl)-1H-benzimidazol-2-yl]carbamate
hydroxyalbendazole = methyl [5-(3-hydroxypropylsulfanyl)-1H-benzimidazol-2-yl]carbamate
Other name(s): CYP2J2 (gene name)
Systematic name: albendazole,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (hydroxylating)
Comments: CYP2J2 is a microsomal cytochrome P-450 monooxygenase that catalyses the hydroxylation of the terminal carbon of the propylsulfanyl chain in albendazole, a broad-spectrum anthelmintic used against gastrointestinal nematodes and the larval stages of cestodes. cf. EC 1.14.14.73, albendazole monooxygenase (sulfoxide-forming).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB
References:
1.  Wu, Z., Lee, D., Joo, J., Shin, J.H., Kang, W., Oh, S., Lee, D.Y., Lee, S.J., Yea, S.S., Lee, H.S., Lee, T. and Liu, K.H. CYP2J2 and CYP2C19 are the major enzymes responsible for metabolism of albendazole and fenbendazole in human liver microsomes and recombinant P450 assay systems. Antimicrob. Agents Chemother. 57 (2013) 5448–5456. [DOI] [PMID: 23959307]
[EC 1.14.14.74 created 2018]
 
 
EC 1.14.14.75
Accepted name: fenbendazole monooxygenase (4′-hydroxylating)
Reaction: fenbendazole + [reduced NADPH—hemoprotein reductase] + O2 = 4′-hydroxyfenbendazole + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of albendazole metabolism, click here
Glossary: fenbendazole = methyl [5-(phenylsulfanyl)-1H-benzimidazol-2-yl]carbamate
4′-hydroxyfenbendazole = methyl [5-(4-hydroxyphenylsulfanyl)-1H-benzimidazol-2-yl]carbamate
albendazole = methyl [5-(propylsulfanyl)-1H-benzimidazol-2-yl]carbamate
Other name(s): CYP2C19 (gene name)
Systematic name: fenbendazole,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (4′-hydroxylating)
Comments: CYP2C19 is microsomal cytochrome P-450 monooxygenase that catalyses the hydroxylation of the benzene ring of fenbendazole, a broad-spectrum anthelmintic used against gastrointestinal nematodes and the larval stages of cestodes. This activity is also carried out by CYP2J2. cf. EC 1.14.14.74, albendazole monooxygenase (hydroxylating). CYP2C19 does not act on albendazole.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB
References:
1.  Wu, Z., Lee, D., Joo, J., Shin, J.H., Kang, W., Oh, S., Lee, D.Y., Lee, S.J., Yea, S.S., Lee, H.S., Lee, T. and Liu, K.H. CYP2J2 and CYP2C19 are the major enzymes responsible for metabolism of albendazole and fenbendazole in human liver microsomes and recombinant P450 assay systems. Antimicrob. Agents Chemother. 57 (2013) 5448–5456. [DOI] [PMID: 23959307]
[EC 1.14.14.75 created 2018]
 
 
EC 1.14.14.76
Accepted name: ent-isokaurene C2/C3-hydroxylase
Reaction: ent-isokaurene + 2 O2 + 2 [reduced NADPH—hemoprotein reductase] = ent-isokaurene-2β,3β-diol + [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(1a) ent-isokaurene + O2 + [reduced NADPH—hemoprotein reductase] = ent-isokauren-2β-ol + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) ent-isokauren-2β-ol + O2 + [reduced NADPH—hemoprotein reductase] = ent-isokaurene-2β,3β-diol + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of biosynthesis of diterpenoids from ent-copalyl diphosphate, click here
Other name(s): CYP71Z6; ent-isokaurene C2-hydroxylase
Systematic name: ent-isokaurene,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (ent-isokaurene-2β,3β-diol forming)
Comments: This cytochrome P-450 (heme thiolate) enzyme has been characterized from the plant Oryza sativa (rice). It may be involved in production of oryzadione.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Wu, Y., Hillwig, M.L., Wang, Q. and Peters, R.J. Parsing a multifunctional biosynthetic gene cluster from rice: biochemical characterization of CYP71Z6 & 7. FEBS Lett. 585 (2011) 3446–3451. [DOI] [PMID: 21985968]
2.  Kitaoka, N., Wu, Y., Xu, M. and Peters, R.J. Optimization of recombinant expression enables discovery of novel cytochrome P450 activity in rice diterpenoid biosynthesis. Appl. Microbiol. Biotechnol. 99 (2015) 7549–7558. [DOI] [PMID: 25758958]
[EC 1.14.14.76 created 2012 as EC 1.14.13.143, transferred 2018 to EC 1.14.14.76]
 
 
EC 1.14.14.77
Accepted name: phenylacetonitrile α-monooxygenase
Reaction: phenylacetonitrile + [reduced NADPH—hemoprotein reductase] + O2 = (R)-mandelonitrile + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): CYP3201B1 (gene name)
Systematic name: phenylacetonitrile,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase [(R)-mandelonitrile-forming]
Comments: The enzyme has been characterized from the cyanogenic millipede Chamberlinius hualienensis. Unlike plant enzymes that can catalyse this reaction (EC 1.14.14.44, phenylacetaldehyde oxime monooxygenase), this enzyme cannot act on phenylacetaldehyde oximes. It can accept (4-hydroxyphenyl)acetonitrile, (2-methylphenyl)acetonitrile, and (3-methylphenyl)acetonitrile as substrates at a lower rate.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Yamaguchi, T., Kuwahara, Y. and Asano, Y. A novel cytochrome P450, CYP3201B1, is involved in (R)-mandelonitrile biosynthesis in a cyanogenic millipede. FEBS Open Bio 7 (2017) 335–347. [DOI] [PMID: 28286729]
[EC 1.14.14.77 created 2018]
 
 
EC 1.14.14.78
Accepted name: phylloquinone ω-hydroxylase
Reaction: phylloquinone + [reduced NADPH—hemoprotein reductase] + O2 = ω-hydroxyphylloquinone + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of vitamin K biosynthesis, click here
Other name(s): vitamin K1 ω-hydroxylase; CYP4F2; CYP4F11
Systematic name: phylloquinone,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (ω-hydroxyphylloquinone forming)
Comments: A cytochrome P-450 (heme-thiolate) protein. Isolated from human tissue. The enzyme will also act on menaquinone-4. Prolonged action of CYP4F2, but not CYP4F11, on the ω hydroxyl group oxidizes it to the corresponding carboxylic acid. CYP4F2 also oxidizes leukotriene B4; see EC 1.14.13.30, leukotriene-B4 20-monooxygenase [1].
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Jin, R., Koop, D.R., Raucy, J.L. and Lasker, J.M. Role of human CYP4F2 in hepatic catabolism of the proinflammatory agent leukotriene B4. Arch. Biochem. Biophys. 359 (1998) 89–98. [DOI] [PMID: 9799565]
2.  Tang, Z., Salamanca-Pinzon, S.G., Wu, Z.L., Xiao, Y. and Guengerich, F.P. Human cytochrome P450 4F11: heterologous expression in bacteria, purification, and characterization of catalytic function. Arch. Biochem. Biophys. 494 (2010) 86–93. [DOI] [PMID: 19932081]
3.  Edson, K.Z., Prasad, B., Unadkat, J.D., Suhara, Y., Okano, T., Guengerich, F.P. and Rettie, A.E. Cytochrome P450-dependent catabolism of vitamin K: ω-hydroxylation catalyzed by human CYP4F2 and CYP4F11. Biochemistry 52 (2013) 8276–8285. [DOI] [PMID: 24138531]
[EC 1.14.14.78 created 2014 as EC 1.14.13.194, transferred 2018 to EC 1.14.14.78]
 
 
EC 1.14.14.79
Accepted name: docosahexaenoic acid ω-hydroxylase
Reaction: docosahexaenoate + [reduced NADPH—hemoprotein reductase] + O2 = 22-hydroxydocosahexaenoate + [oxidized NADPH—hemoprotein reductase] + H2O
Glossary: docosahexaenoate = (4Z,7Z,10Z,13Z,16Z,19Z)-docosa-4,7,10,13,16,19-hexaenoate
icosapentaenoate = (5Z,8Z,11Z,14Z,17Z)-icosa-5,8,11,14,17-pentaenoate
Other name(s): CYP4F3B; CYP4V2; docosahexaenoate,NADPH:O2 oxidoreductase (22-hydroxydocosahexaenoate forming)
Systematic name: docosahexaenoate,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (22-hydroxydocosahexaenoate forming)
Comments: A cytochrome P-450 (heme-thiolate) protein isolated from human eye tissue. Defects in the enzyme are associated with Bietti crystalline corneoretinal dystrophy. The enzyme also produces some 21-hydroxydocosahexaenoate. Acts in a similar way on icosapentaenoic acid.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Nakano, M., Kelly, E.J., Wiek, C., Hanenberg, H. and Rettie, A.E. CYP4V2 in Bietti’s crystalline dystrophy: ocular localization, metabolism of ω-3-polyunsaturated fatty acids, and functional deficit of the p.H331P variant. Mol. Pharmacol. 82 (2012) 679–686. [DOI] [PMID: 22772592]
[EC 1.14.14.79 created 2014 as EC 1.14.13.199, transferred 2018 to EC 1.14.14.79]
 
 
EC 1.14.14.80
Accepted name: long-chain fatty acid ω-monooxygenase
Reaction: a long-chain fatty acid + [reduced NADPH—hemoprotein reductase] + O2 = an ω-hydroxy-long-chain fatty acid + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): CYP704B1 (gene name); CYP52M1 (gene name); CYP4A (gene name); CYP86A (gene name)
Systematic name: long-chain fatty acid,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (ω-hydroxylating)
Comments: A cytochrome P-450 (heme thiolate) enzyme. The plant enzyme CYP704B1, which is involved in the synthesis of sporopollenin, a complex polymer found at the outer layer of spores and pollen, acts on palmitate (18:0), stearate (18:0) and oleate (18:1). The plant enzyme CYP86A1 also acts on laurate (12:0). The enzyme from the yeast Starmerella bombicola (CYP52M1) acts on C16 to C20 saturated and unsaturated fatty acids and can also hydroxylate the (ω-1) position. The mammalian enzyme CYP4A acts on laurate (12:0), myristate (14:0), palmitate (16:0), oleate (18:1), and arachidonate (20:4).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Benveniste, I., Tijet, N., Adas, F., Philipps, G., Salaun, J.P. and Durst, F. CYP86A1 from Arabidopsis thaliana encodes a cytochrome P450-dependent fatty acid ω-hydroxylase. Biochem. Biophys. Res. Commun. 243 (1998) 688–693. [DOI] [PMID: 9500987]
2.  Hoch, U., Zhang, Z., Kroetz, D.L. and Ortiz de Montellano, P.R. Structural determination of the substrate specificities and regioselectivities of the rat and human fatty acid ω-hydroxylases. Arch. Biochem. Biophys. 373 (2000) 63–71. [DOI] [PMID: 10620324]
3.  Dobritsa, A.A., Shrestha, J., Morant, M., Pinot, F., Matsuno, M., Swanson, R., Møller, B.L. and Preuss, D. CYP704B1 is a long-chain fatty acid ω-hydroxylase essential for sporopollenin synthesis in pollen of Arabidopsis. Plant Physiol. 151 (2009) 574–589. [DOI] [PMID: 19700560]
4.  Huang, F.C., Peter, A. and Schwab, W. Expression and characterization of CYP52 genes involved in the biosynthesis of sophorolipid and alkane metabolism from Starmerella bombicola. Appl. Environ. Microbiol. 80 (2014) 766–776. [DOI] [PMID: 24242247]
[EC 1.14.14.80 created 2015 as EC 1.14.13.205, transferred 2018 to EC 1.14.14.80]
 
 
EC 1.14.14.81
Accepted name: flavanoid 3′,5′-hydroxylase
Reaction: a flavanone + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = a 3′,5′-dihydroxyflavanone + 2 [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(1a) a flavanone + [reduced NADPH—hemoprotein reductase] + O2 = a 3′-hydroxyflavanone + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) a 3′-hydroxyflavanone + [reduced NADPH—hemoprotein reductase] + O2 = a 3′,5′-dihydroxyflavanone + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of myricetin biosynthesis, click here, for diagram of the biosynthesis of naringenin derivatives, click here and for diagram of flavonoid biosynthesis, click here
Other name(s): flavonoid 3′,5′-hydroxylase
Systematic name: flavanone,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (3′,5′-dihydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein found in plants. The 3′,5′-dihydroxyflavanone is formed via the 3′-hydroxyflavanone. In Petunia hybrida the enzyme acts on naringenin, eriodictyol, dihydroquercetin (taxifolin) and dihydrokaempferol (aromadendrin). The enzyme catalyses the hydroxylation of 5,7,4′-trihydroxyflavanone (naringenin) at either the 3′ position to form eriodictyol or at both the 3′ and 5′ positions to form 5,7,3′,4′,5′-pentahydroxyflavanone (dihydrotricetin). The enzyme also catalyses the hydroxylation of 3,5,7,3′,4′-pentahydroxyflavanone (taxifolin) at the 5′ position, forming ampelopsin.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 94047-23-1
References:
1.  Menting, J., Scopes, R.K. and Stevenson, T.W. Characterization of flavonoid 3′,5′-hydroxylase in microsomal membrane fraction of Petunia hybrida flowers. Plant Physiol. 106 (1994) 633–642. [PMID: 12232356]
2.  Shimada, Y., Nakano-Shimada, R., Ohbayashi, M., Okinaka, Y., Kiyokawa, S. and Kikuchi, Y. Expression of chimeric P450 genes encoding flavonoid-3′, 5′-hydroxylase in transgenic tobacco and petunia plants1. FEBS Lett. 461 (1999) 241–245. [DOI] [PMID: 10567704]
3.  de Vetten, N., ter Horst, J., van Schaik, H.P., de Boer, A., Mol, J. and Koes, R. A cytochrome b5 is required for full activity of flavonoid 3′, 5′-hydroxylase, a cytochrome P450 involved in the formation of blue flower colors. Proc. Natl. Acad. Sci. USA 96 (1999) 778–783. [DOI] [PMID: 9892710]
[EC 1.14.14.81 created 2004 as EC 1.14.13.88, transferred 2018 to EC 1.14.14.81]
 
 
EC 1.14.14.82
Accepted name: flavonoid 3′-monooxygenase
Reaction: a flavonoid + [reduced NADPH—hemoprotein reductase] + O2 = a 3′-hydroxyflavonoid + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of flavonoid biosynthesis, click here and for diagram of the biosynthesis of naringenin derivatives, click here
Other name(s): CYP75B1 (gene name); flavonoid 3′-hydroxylase; flavonoid 3-hydroxylase (incorrect); NADPH:flavonoid-3′-hydroxylase (incorrect); flavonoid 3-monooxygenase (incorrect)
Systematic name: flavonoid,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (3′-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein found in plants. Acts on a number of flavonoids, including the flavanone naringenin and the flavone apigenin. Does not act on 4-coumarate or 4-coumaroyl-CoA.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 75991-44-5
References:
1.  Forkmann, G., Heller, W. and Grisebach, H. Anthocyanin biosynthesis in flowers of Matthiola incana flavanone 3- and flavonoid 3′-hydroxylases. Z. Naturforsch. C: Biosci. 35 (1980) 691–695.
2.  Brugliera, F., Barri-Rewell, G., Holton, T.A. and Mason, J.G. Isolation and characterization of a flavonoid 3′-hydroxylase cDNA clone corresponding to the Ht1 locus of Petunia hybrida. Plant J. 19 (1999) 441–451. [PMID: 10504566]
3.  Schoenbohm, C., Martens, S., Eder, C., Forkmann, G. and Weisshaar, B. Identification of the Arabidopsis thaliana flavonoid 3′-hydroxylase gene and functional expression of the encoded P450 enzyme. Biol. Chem. 381 (2000) 749–753. [PMID: 11030432]
[EC 1.14.14.82 created 1983 as EC 1.14.13.21, transferred 2018 to EC 1.14.14.82]
 
 
EC 1.14.14.83
Accepted name: geraniol 8-hydroxylase
Reaction: geraniol + [reduced NADPH—hemoprotein reductase] + O2 = (6E)-8-hydroxygeraniol + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of acyclic monoterpenoid biosynthesis, click here
Other name(s): CYP76B6 (gene name); G10H (gene name)
Systematic name: geraniol,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (8-hydroxylating)
Comments: A cytochrome P-450 (heme thiolate) protein found in plants. Also hydroxylates nerol and citronellol, cf. EC 1.14.14.84, linalool 8-monooxygenase. The recommended numbering of geraniol gives 8-hydroxygeraniol as the product rather than 10-hydroxygeraniol as used by references 1-3. See prenol nomenclature Pr-1. The cloned enzyme also catalysed, but less efficiently, the 3′-hydroxylation of naringenin (cf. EC 1.14.14.82, flavonoid 3′-monooxygenase) [3].
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Collu, G., Unver, N., Peltenburg-Looman, A.M., van der Heijden, R., Verpoorte, R. and Memelink, J. Geraniol 10-hydroxylase, a cytochrome P450 enzyme involved in terpenoid indole alkaloid biosynthesis. FEBS Lett. 508 (2001) 215–220. [DOI] [PMID: 11718718]
2.  Wang, J., Liu, Y., Cai, Y., Zhang, F., Xia, G. and Xiang, F. Cloning and functional analysis of geraniol 10-hydroxylase, a cytochrome P450 from Swertia mussotii Franch. Biosci. Biotechnol. Biochem. 74 (2010) 1583–1590. [PMID: 20699579]
3.  Sung, P.H., Huang, F.C., Do, Y.Y. and Huang, P.L. Functional expression of geraniol 10-hydroxylase reveals its dual function in the biosynthesis of terpenoid and phenylpropanoid. J. Agric. Food Chem. 59 (2011) 4637–4643. [DOI] [PMID: 21504162]
[EC 1.14.14.83 created 2012 as EC 1.14.13.152, transferred 2018 to EC 1.14.14.83]
 
 
EC 1.14.14.84
Accepted name: linalool 8-monooxygenase
Reaction: linalool + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = (6E)-8-oxolinalool + 2 [oxidized NADPH—hemoprotein reductase] + 3 H2O (overall reaction)
(1a) linalool + [reduced NADPH—hemoprotein reductase] + O2 = (6E)-8-hydroxylinalool + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) (6E)-8-hydroxylinalool + [reduced NADPH—hemoprotein reductase] + O2 = (6E)-8-oxolinalool + [oxidized NADPH—hemoprotein reductase] + 2 H2O
For diagram of acyclic monoterpenoid biosynthesis, click here
Glossary: linalool = 3,7-dimethylocta-1,6-dien-3-ol
Other name(s): P-450lin; CYP111
Systematic name: linalool,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (8-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein found in plants. The secondary electron donor is a specific [2Fe-2S] ferredoxin from the same bacterial strain.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Ullah, A.J., Murray, R.I., Bhattacharyya, P.K., Wagner, G.C. and Gunsalus, I.C. Protein components of a cytochrome P-450 linalool 8-methyl hydroxylase. J. Biol. Chem. 265 (1990) 1345–1351. [PMID: 2295633]
2.  Ropp, J.D., Gunsalus, I.C. and Sligar, S.G. Cloning and expression of a member of a new cytochrome P-450 family: cytochrome P-450lin (CYP111) from Pseudomonas incognita. J. Bacteriol. 175 (1993) 6028–6037. [DOI] [PMID: 8376348]
[EC 1.14.14.84 created 1989 as EC 1.14.99.28, transferred 2012 to EC 1.14.13.151, transferred 2018 to EC 1.14.14.84]
 
 
EC 1.14.14.85
Accepted name: 7-deoxyloganin 7-hydroxylase
Reaction: 7-deoxyloganin + [reduced NADPH—hemoprotein reductase] + O2 = loganin + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of secologanin biosynthesis, click here
Systematic name: 7-deoxyloganin,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (7α-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein found in plants.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 335305-40-3
References:
1.  Katano, N., Yamamoto, H., Iio, R. and Inoue, K. 7-Deoxyloganin 7-hydroxylase in Lonicera japonica cell cultures. Phytochemistry 58 (2001) 53–58. [DOI] [PMID: 11524113]
[EC 1.14.14.85 created 2002 as EC 1.14.13.74, transferred 2018 to EC 1.14.14.85]
 
 
EC 1.14.14.86
Accepted name: ent-kaurene monooxygenase
Reaction: ent-kaur-16-ene + 3 [reduced NADPH—hemoprotein reductase] + 3 O2 = ent-kaur-16-en-19-oate + 3 [oxidized NADPH—hemoprotein reductase] + 4 H2O (overall reaction)
(1a) ent-kaur-16-ene + [reduced NADPH—hemoprotein reductase] + O2 = ent-kaur-16-en-19-ol + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) ent-kaur-16-en-19-ol + [reduced NADPH—hemoprotein reductase] + O2 = ent-kaur-16-en-19-al + [oxidized NADPH—hemoprotein reductase] + 2 H2O
(1c) ent-kaur-16-en-19-al + [reduced NADPH—hemoprotein reductase] + O2 = ent-kaur-16-en-19-oate + [oxidized NADPH—hemoprotein reductase] + H2O
For diagram of gibberellin A12 biosynthesis, click here
Other name(s): ent-kaurene oxidase (misleading)
Systematic name: ent-kaur-16-ene,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (hydroxylating)
Comments: A cytochrome P-450 (heme thiolate) protein found in plants. Catalyses three successive oxidations of the 4-methyl group of ent-kaurene giving kaurenoic acid.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 149565-67-3
References:
1.  Ashman, P.J., Mackenzie, A. and Bramley, P.M. Characterization of ent-kaurene oxidase activity from Gibberella fujikuroi. Biochim. Biophys. Acta 1036 (1990) 151–157. [DOI] [PMID: 2223832]
2.  Archer, C., Ashman, P.J., Hedden, P., Bowyer, J.R. and Bramley, P.M. Purification of ent-kaurene oxidase from Gibberella fujikuroi and Cucurbita maxima. Biochem. Soc. Trans. 20 (1992) 218. [PMID: 1397591]
3.  Helliwell, C.A., Poole, A., Peacock, W.J. and Dennis, E.S. Arabidopsis ent-kaurene oxidase catalyzes three steps of gibberellin biosynthesis. Plant Physiol. 119 (1999) 507–510. [PMID: 9952446]
[EC 1.14.14.86 created 2002 as EC 1.14.13.78, transferred 2018 to EC 1.14.14.86]
 
 
EC 1.14.14.87
Accepted name: 2-hydroxyisoflavanone synthase
Reaction: (1) liquiritigenin + O2 + [reduced NADPH—hemoprotein reductase] = 2,4′,7-trihydroxyisoflavanone + H2O + [oxidized NADPH—hemoprotein reductase]
(2) (2S)-naringenin + O2 + [reduced NADPH—hemoprotein reductase] = 2,4′,5,7-tetrahydroxyisoflavanone + H2O + [oxidized NADPH—hemoprotein reductase]
For diagram of daidzein biosynthesis, click here
Glossary: liquiritigenin = 4′,7-dihydroxyflavanone
(2S)-naringenin = 4′,5,7-dihydroxyflavanone
2,4′,5,7-tetrahydroxyisoflavanone = 2-hydroxy-2,3-dihydrogenistein
Other name(s): CYP93C; IFS; isoflavonoid synthase
Systematic name: liquiritigenin, [reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (hydroxylating, aryl migration)
Comments: A cytochrome P-450 (heme thiolate) protein found in plants. The reaction involves the migration of the 2-phenyl group of the flavanone to the 3-position of the isoflavanone. The 2-hydroxyl group is derived from the oxygen molecule. EC 4.2.1.105, 2-hydroxyisoflavanone dehydratase, acts on the products with loss of water and formation of genistein and daidzein, respectively.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Kochs, G. and Grisebach, H. Enzymic synthesis of isoflavones. Eur. J. Biochem. 155 (1986) 311–318. [DOI] [PMID: 3956488]
2.  Hashim, M.F., Hakamatsuka, T., Ebizuka, Y. and Sankawa, U. Reaction mechanism of oxidative rearrangement of flavanone in isoflavone biosynthesis. FEBS Lett. 271 (1990) 219–222. [DOI] [PMID: 2226805]
3.  Steele, C. L., Gijzen, M., Qutob, D. and Dixon, R.A. Molecular characterization of the enzyme catalyzing the aryl migration reaction of isoflavonoid biosynthesis in soybean. Arch. Biochem. Biophys. 367 (1999) 146–150. [DOI] [PMID: 10375412]
4.  Sawada, Y., Kinoshita, K., Akashi, T., Aoki, T. and Ayabe, S. Key amino acid residues required for aryl migration catalysed by the cytochrome P450 2-hydroxyisoflavanone synthase. Plant J. 31 (2002) 555–564. [DOI] [PMID: 12207646]
5.  Sawada, Y. and Ayabe, S. Multiple mutagenesis of P450 isoflavonoid synthase reveals a key active-site residue. Biochem. Biophys. Res. Commun. 330 (2005) 907–913. [DOI] [PMID: 15809082]
[EC 1.14.14.87 created 2011 as EC 1.14.13.136, modified 2013, transferred 2018 to EC 1.14.14.87]
 
 
EC 1.14.15.27
Accepted name: β-dihydromenaquinone-9 ω-hydroxylase
Reaction: β-dihydromenaquinone-9 + 2 reduced ferredoxin [iron-sulfur] cluster + O2 = ω-hydroxy-β-dihydromenaquinone-9 + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
For diagram of vitamin K biosynthesis, click here
Glossary: β-dihydromenaquinone-9 = MK-9(II-H2) = 2-methyl-3-[(2E,10E,14E,18E,22E,26E,30E,33E)-3,7,11,15,19,23,27,31,35-nonamethylhexatriaconta-2,10,14,18,22,26,30,33-octaen-1-yl]naphthalene-1,4-dione
Other name(s): cyp128 (gene name)
Systematic name: β-dihydromenaquinone-9,reduced ferredoxin:oxygen oxidoreductase (ω-hydroxylating)
Comments: The bacterial cytochrome P-450 enzyme is involved in the biosynthesis of ω-sulfo-β-dihydromenaquinone-9 by members of the Mycobacterium tuberculosis complex.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Holsclaw, C.M., Sogi, K.M., Gilmore, S.A., Schelle, M.W., Leavell, M.D., Bertozzi, C.R. and Leary, J.A. Structural characterization of a novel sulfated menaquinone produced by stf3 from Mycobacterium tuberculosis. ACS Chem. Biol. 3 (2008) 619–624. [DOI] [PMID: 18928249]
2.  Sogi, K.M., Holsclaw, C.M., Fragiadakis, G.K., Nomura, D.K., Leary, J.A. and Bertozzi, C.R. Biosynthesis and regulation of sulfomenaquinone, a metabolite associated with virulence in Mycobacterium tuberculosis. ACS Infect Dis 2 (2016) 800–806. [PMID: 27933784]
[EC 1.14.15.27 created 2018]
 
 
EC 1.14.15.28
Accepted name: cholest-4-en-3-one 26-monooxygenase [(25R)-3-oxocholest-4-en-26-oate forming]
Reaction: cholest-4-en-3-one + 6 reduced [2Fe-2S] ferredoxin + 3 O2 = (25R)-3-oxocholest-4-en-26-oate + 6 oxidized [2Fe-2S] ferredoxin + 4 H2O (overall reaction)
(1a) cholest-4-en-3-one + 2 reduced [2Fe-2S] ferredoxin + O2 = (25R)-26-hydroxycholest-4-en-3-one + 2 oxidized [2Fe-2S] ferredoxin + H2O
(1b) (25R)-26-hydroxycholest-4-en-3-one + 2 reduced [2Fe-2S] ferredoxin + O2 = (25R)-26-oxocholest-4-en-3-one + 2 oxidized [2Fe-2S] ferredoxin + 2 H2O
(1c) (25R)-26-oxocholest-4-en-3-one + 2 reduced [2Fe-2S] ferredoxin + O2 = (25R)-3-oxocholest-4-en-26-oate + 2 oxidized [2Fe-2S] ferredoxin + H2O
Other name(s): CYP142
Systematic name: cholest-4-en-3-one,reduced [2Fe-2S] ferredoxin:oxygen oxidoreductase [(25R)-3-oxocholest-4-en-26-oate forming]
Comments: This cytochrome P-450 (heme-thiolate) enzyme, found in several bacterial pathogens, is involved in degradation of the host cholesterol. It catalyses the hydroxylation of the C-26 carbon, followed by oxidation of the alcohol to the carboxylic acid via the aldehyde intermediate, initiating the degradation of the alkyl side-chain of cholesterol. The products are exclusively in the (25R) conformation. The enzyme also accepts cholesterol as a substrate. cf. EC 1.14.15.29, cholest-4-en-3-one 26-monooxygenase [(25S)-3-oxocholest-4-en-26-oate forming]. The enzyme can receive electrons from ferredoxin reductase in vitro, its natural electron donor is not known yet.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Driscoll, M.D., McLean, K.J., Levy, C., Mast, N., Pikuleva, I.A., Lafite, P., Rigby, S.E., Leys, D. and Munro, A.W. Structural and biochemical characterization of Mycobacterium tuberculosis CYP142: evidence for multiple cholesterol 27-hydroxylase activities in a human pathogen. J. Biol. Chem. 285 (2010) 38270–38282. [DOI] [PMID: 20889498]
2.  Johnston, J.B., Ouellet, H. and Ortiz de Montellano, P.R. Functional redundancy of steroid C26-monooxygenase activity in Mycobacterium tuberculosis revealed by biochemical and genetic analyses. J. Biol. Chem. 285 (2010) 36352–36360. [DOI] [PMID: 20843794]
[EC 1.14.15.28 created 2016 as EC 1.14.13.221, transferred 2018 to EC 1.14.15.28]
 
 
EC 1.14.15.29
Accepted name: cholest-4-en-3-one 26-monooxygenase [(25S)-3-oxocholest-4-en-26-oate forming]
Reaction: cholest-4-en-3-one + 6 reduced ferredoxin [iron-sulfur] cluster + 6 H+ + 3 O2 = (25S)-3-oxocholest-4-en-26-oate + 6 oxidized ferredoxin [iron-sulfur] cluster + 4 H2O (overall reaction)
(1a) cholest-4-en-3-one + 2 reduced ferredoxin [iron-sulfur] cluster + 2 H+ + O2 = (25S)-26-hydroxycholest-4-en-3-one + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
(1b) (25S)-26-hydroxycholest-4-en-3-one + 2 reduced ferredoxin [iron-sulfur] cluster + 2 H+ + O2 = (25S)-26-oxocholest-4-en-3-one + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
(1c) (25S)-26-oxocholest-4-en-3-one + 2 reduced ferredoxin [iron-sulfur] cluster + 2 H+ + O2 = (25S)-3-oxocholest-4-en-26-oate + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
Other name(s): CYP125; CYP125A1; cholest-4-en-3-one 27-monooxygenase (misleading); cholest-4-en-3-one,NADH:oxygen oxidoreductase (26-hydroxylating); cholest-4-en-3-one 26-monooxygenase (ambiguous)
Systematic name: cholest-4-en-3-one,[reduced ferredoxin]:oxygen oxidoreductase [(25S)-3-oxocholest-4-en-26-oate forming]
Comments: A cytochrome P-450 (heme-thiolate) protein found in several bacterial pathogens. The enzyme is involved in degradation of the host’s cholesterol. It catalyses the hydroxylation of the C-26 carbon, followed by oxidation of the alcohol to the carboxylic acid via the aldehyde intermediate, initiating the degradation of the alkyl side-chain of cholesterol [4]. The products are exclusively in the (25S) configuration. The enzyme is part of a two-component system that also includes a ferredoxin reductase (most likely KshB, which also interacts with EC 1.14.15.30, 3-ketosteroid 9α-monooxygenase). The enzyme also accepts cholesterol as a substrate. cf. EC 1.14.15.28, cholest-4-en-3-one 27-monooxygenase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Rosloniec, K.Z., Wilbrink, M.H., Capyk, J.K., Mohn, W.W., Ostendorf, M., van der Geize, R., Dijkhuizen, L. and Eltis, L.D. Cytochrome P450 125 (CYP125) catalyses C26-hydroxylation to initiate sterol side-chain degradation in Rhodococcus jostii RHA1. Mol. Microbiol. 74 (2009) 1031–1043. [DOI] [PMID: 19843222]
2.  McLean, K.J., Lafite, P., Levy, C., Cheesman, M.R., Mast, N., Pikuleva, I.A., Leys, D. and Munro, A.W. The Structure of Mycobacterium tuberculosis CYP125: molecular basis for cholesterol binding in a P450 needed for host infection. J. Biol. Chem. 284 (2009) 35524–35533. [DOI] [PMID: 19846552]
3.  Capyk, J.K., Kalscheuer, R., Stewart, G.R., Liu, J., Kwon, H., Zhao, R., Okamoto, S., Jacobs, W.R., Jr., Eltis, L.D. and Mohn, W.W. Mycobacterial cytochrome P450 125 (Cyp125) catalyzes the terminal hydroxylation of C27 steroids. J. Biol. Chem. 284 (2009) 35534–35542. [DOI] [PMID: 19846551]
4.  Ouellet, H., Guan, S., Johnston, J.B., Chow, E.D., Kells, P.M., Burlingame, A.L., Cox, J.S., Podust, L.M. and de Montellano, P.R. Mycobacterium tuberculosis CYP125A1, a steroid C27 monooxygenase that detoxifies intracellularly generated cholest-4-en-3-one. Mol. Microbiol. 77 (2010) 730–742. [DOI] [PMID: 20545858]
[EC 1.14.15.29 created 2012 as EC 1.14.13.141, modified 2016, transferred 2018 to EC 1.14.15.29]
 
 
EC 1.14.15.30
Accepted name: 3-ketosteroid 9α-monooxygenase
Reaction: androsta-1,4-diene-3,17-dione + 2 reduced ferredoxin [iron-sulfur] cluster + 2 H+ + O2 = 9α-hydroxyandrosta-1,4-diene-3,17-dione + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
Other name(s): KshA; 3-ketosteroid 9α-hydroxylase
Systematic name: androsta-1,4-diene-3,17-dione,[reduced ferredoxin]:oxygen oxidoreductase (9α-hydroxylating)
Comments: The enzyme is involved in the cholesterol degradation pathway of several bacterial pathogens, such as Mycobacterium tuberculosis. It forms a two-component system with a ferredoxin reductase (KshB). The enzyme contains a Rieske-type iron-sulfur center and non-heme iron. The product of the enzyme is unstable, and spontaneously converts to 3-hydroxy-9,10-seconandrost-1,3,5(10)-triene-9,17-dione.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, UM-BBD
References:
1.  Petrusma, M., Dijkhuizen, L. and van der Geize, R. Rhodococcus rhodochrous DSM 43269 3-ketosteroid 9α-hydroxylase, a two-component iron-sulfur-containing monooxygenase with subtle steroid substrate specificity. Appl. Environ. Microbiol. 75 (2009) 5300–5307. [DOI] [PMID: 19561185]
2.  Capyk, J.K., D'Angelo, I., Strynadka, N.C. and Eltis, L.D. Characterization of 3-ketosteroid 9α-hydroxylase, a Rieske oxygenase in the cholesterol degradation pathway of Mycobacterium tuberculosis. J. Biol. Chem. 284 (2009) 9937–9946. [DOI] [PMID: 19234303]
3.  Capyk, J.K., Casabon, I., Gruninger, R., Strynadka, N.C. and Eltis, L.D. Activity of 3-ketosteroid 9α-hydroxylase (KshAB) indicates cholesterol side chain and ring degradation occur simultaneously in Mycobacterium tuberculosis. J. Biol. Chem. 286 (2011) 40717–40724. [DOI] [PMID: 21987574]
[EC 1.14.15.30 created 2012 as EC 1.14.13.142, transferred 2018 to EC 1.14.15.30]
 
 
*EC 1.14.19.9
Accepted name: tryptophan 7-halogenase
Reaction: tryptophan + FADH2 + chloride + O2 + H+ = 7-chloro-L-tryptophan + FAD + 2 H2O
For diagram of rebeccamycin biosynthesis, click here
Other name(s): prnA (gene name); rebH (gene name); ktzQ (gene name)
Systematic name: L-tryptophan:FADH2 oxidoreductase (7-halogenating)
Comments: A flavin-dependent halogenase. The enzyme from the bacterium Lechevalieria aerocolonigenes catalyses the initial step in the biosynthesis of rebeccamycin [2]. It utilizes molecular oxygen to oxidize the FADH2 cofactor, giving C4a-hydroperoxyflavin, which then reacts with chloride to produce a hypochlorite ion. The latter reacts with an active site lysine to generate a chloramine, which chlorinates the substrate. Also acts on bromide ion. cf. EC 1.14.19.58, tryptophan 5-halogenase, and EC 1.14.19.59, tryptophan 6-halogenase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Dong, C., Kotzsch, A., Dorward, M., van Pee, K.H. and Naismith, J.H. Crystallization and X-ray diffraction of a halogenating enzyme, tryptophan 7-halogenase, from Pseudomonas fluorescens. Acta Crystallogr. D Biol. Crystallogr. 60 (2004) 1438–1440. [DOI] [PMID: 15272170]
2.  Yeh, E., Garneau, S. and Walsh, C.T. Robust in vitro activity of RebF and RebH, a two-component reductase/halogenase, generating 7-chlorotryptophan during rebeccamycin biosynthesis. Proc. Natl. Acad. Sci. USA 102 (2005) 3960–3965. [DOI] [PMID: 15743914]
3.  Bitto, E., Huang, Y., Bingman, C.A., Singh, S., Thorson, J.S. and Phillips Jr., G.N. The structure of flavin-dependent tryptophan 7-halogenase RebH. Proteins Struct. Funct. Genet. 70 (2008) 289–293. [PMID: 17876823]
4.  Heemstra, J.R., Jr. and Walsh, C.T. Tandem action of the O2- and FADH2-dependent halogenases KtzQ and KtzR produce 6,7-dichlorotryptophan for kutzneride assembly. J. Am. Chem. Soc. 130 (2008) 14024–14025. [DOI] [PMID: 18828589]
[EC 1.14.19.9 created 2009 as EC 1.14.14.7, transferred 2014 to EC 1.14.19.9, modified 2018]
 
 
EC 1.14.19.54
Accepted name: 1,2-dehydroreticuline synthase
Reaction: (S)-reticuline + [reduced NADPH—hemoprotein reductase] + O2 = 1,2-dehydroreticuline + [oxidized NADPH—hemoprotein reductase] + 2 H2O
For diagram of thebaine biosynthesis, click here
Glossary: reticuline = 1-(3-hydroxy-4-methoxybenzyl)-6-methoxy-2-methyl-1,2,3,4-tetrahydroisoquinolin-7-ol
Other name(s): STORR; CYP82Y2 (gene name); DRS (gene name)
Systematic name: (S)-reticuline,[reduced NADPH—hemoprotein reductase]:oxygen 1,2-oxidoreductase
Comments: A P-450 (heme-thiolate) cytochrome. The enzyme from Papaver rhoeas (field poppy) is specific for (S)-reticuline and does not act on the (R)-form. The enzyme from Papaver somniferum (opium poppy), which is involved in the biosynthesis of morphine and related alkaloids, forms a fusion protein with EC 1.5.1.27, 1,2-dehydroreticulinium reductase (NADPH), which catalyses the reduction of 1,2-dehydroreticuline to (R)-reticuline, thus forming an epimerase system that converts (S)-reticuline to (R)-reticuline.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Hirata, K., Poeaknapo, C., Schmidt, J. and Zenk, M.H. 1,2-Dehydroreticuline synthase, the branch point enzyme opening the morphinan biosynthetic pathway. Phytochemistry 65 (2004) 1039–1046. [DOI] [PMID: 15110683]
2.  Winzer, T., Kern, M., King, A.J., Larson, T.R., Teodor, R.I., Donninger, S.L., Li, Y., Dowle, A.A., Cartwright, J., Bates, R., Ashford, D., Thomas, J., Walker, C., Bowser, T.A. and Graham, I.A. Morphinan biosynthesis in opium poppy requires a P450-oxidoreductase fusion protein. Science 349 (2015) 309–312. [DOI] [PMID: 26113639]
3.  Farrow, S.C., Hagel, J.M., Beaudoin, G.A., Burns, D.C. and Facchini, P.J. Stereochemical inversion of (S)-reticuline by a cytochrome P450 fusion in opium poppy. Nat. Chem. Biol. 11 (2015) 728–732. [DOI] [PMID: 26147354]
[EC 1.14.19.54 created 2018]
 
 
EC 1.14.19.55
Accepted name: 4-hydroxybenzoate brominase (decarboxylating)
Reaction: (1) 4-hydroxybenzoate + 2 NADPH + 2 bromide + 2 O2 + 2 H+ = 2,4-dibromophenol + 2 NADP+ + CO2 + 4 H2O (overall reaction)
(1a) 4-hydroxybenzoate + NADPH + bromide + O2 + H+ = 3-bromo-4-hydroxybenzoate + NADP+ + 2 H2O
(1b) 3-bromo-4-hydroxybenzoate + NADPH + bromide + O2 + H+ = 2,4-dibromophenol + NADP+ + CO2 + 2 H2O
(2) 3,4-dihydroxybenzoate + 2 NADPH + 2 bromide + 2 O2 + 2 H+ = 3,5-dibromobenzene-1,2-diol + 2 NADP+ + CO2 + 4 H2O (overall reaction)
(2a) 3,4-dihydroxybenzoate + NADPH + bromide + O2 + H+ = 3-bromo-4,5-dihydroxybenzoate + NADP+ + 2 H2O
(2b) 3-bromo-4,5-dihydroxybenzoate + NADPH + bromide + O2 + H+ = 3,5-dibromobenzene-1,2-diol + NADP+ + CO2 + 2 H2O
Other name(s): bmp5 (gene name)
Systematic name: 4-hydroxybenzoate:NADPH oxidoreductase (brominating, decarboxylating)
Comments: Contains FAD. The enzyme, described from epiphytic marine bacteria of the genera Pseudoalteromonas and Marinomonas, is an unusual single-component FAD-dependent halogenase that contains a distinct NAD(P)H binding domain and does not require an additional flavin reductase for activity. The enzyme catalyses a bromination of its substrate, followed by a second bromination concurrent with decarboxylation.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Agarwal, V., El Gamal, A.A., Yamanaka, K., Poth, D., Kersten, R.D., Schorn, M., Allen, E.E. and Moore, B.S. Biosynthesis of polybrominated aromatic organic compounds by marine bacteria. Nat. Chem. Biol. 10 (2014) 640–647. [DOI] [PMID: 24974229]
2.  Agarwal, V. and Moore, B.S. Enzymatic synthesis of polybrominated dioxins from the marine environment. ACS Chem. Biol. 9 (2014) 1980–1984. [DOI] [PMID: 25061970]
[EC 1.14.19.55 created 2018]
 
 
EC 1.14.19.56
Accepted name: 1H-pyrrole-2-carbonyl-[peptidyl-carrier protein] chlorinase
Reaction: 1H-pyrrole-2-carbonyl-[PltL peptidyl-carrier protein] + 2 FADH2 + 2 chloride + 2 O2 = 4,5-dichloro-1H-pyrrole-2-carbonyl-[PltL peptidyl-carrier protein] + 2 FAD + 4 H2O (overall reaction)
(1a) 1H-pyrrole-2-carbonyl-[PltL peptidyl-carrier protein] + FADH2 + chloride + O2 = 5-chloro-1H-pyrrole-2-carbonyl-[PltL peptidyl-carrier protein] + FAD + 2 H2O
(1b) 5-chloro-1H-pyrrole-2-carbonyl-[PltL peptidyl-carrier protein] + FADH2 + chloride + O2 = 4,5-dichloro-1H-pyrrole-2-carbonyl-[PltL peptidyl-carrier protein] + FAD + H2O
Glossary: pyoluteorin = 4,5-dichloro-1H-pyrrol-2-yl 2,6-dihydroxyphenyl
Other name(s): pltA (gene name)
Systematic name: 1H-pyrrole-2-carbonyl-[peptidyl-carrier protein]:FADH2 oxidoreductase (chlorinating)
Comments: The enzyme, characterized from the bacterium Pseudomonas protegens Pf-5, is a flavin-dependent chlorinase that participates in the biosynthesis of the antibacterial and antifungal compound pyoluteorin.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Nowak-Thompson, B., Chaney, N., Wing, J.S., Gould, S.J. and Loper, J.E. Characterization of the pyoluteorin biosynthetic gene cluster of Pseudomonas fluorescens Pf-5. J. Bacteriol. 181 (1999) 2166–2174. [PMID: 10094695]
2.  Dorrestein, P.C., Yeh, E., Garneau-Tsodikova, S., Kelleher, N.L. and Walsh, C.T. Dichlorination of a pyrrolyl-S-carrier protein by FADH2-dependent halogenase PltA during pyoluteorin biosynthesis. Proc. Natl Acad. Sci. USA 102 (2005) 13843–13848. [DOI] [PMID: 16162666]
3.  Pang, A.H., Garneau-Tsodikova, S. and Tsodikov, O.V. Crystal structure of halogenase PltA from the pyoluteorin biosynthetic pathway. J. Struct. Biol. 192 (2015) 349–357. [DOI] [PMID: 26416533]
[EC 1.14.19.56 created 2018]
 
 
EC 1.14.19.57
Accepted name: 1H-pyrrole-2-carbonyl-[peptidyl-carrier protein] brominase
Reaction: 1H-pyrrole-2-carbonyl-[Bmp1 peptidyl-carrier protein] + 3 FADH2 + 3 bromide + 3 O2 = 3,4,5-tribromo-1H-pyrrole-2-carbonyl-[Bmp1 peptidyl-carrier protein] + 3 FAD + 6 H2O (overall reaction)
(1a) 1H-pyrrole-2-carbonyl-[Bmp1 peptidyl-carrier protein] + FADH2 + bromide + O2 = 5-bromo-1H-pyrrole-2-carbonyl-[Bmp1 peptidyl-carrier protein] + FAD + 2 H2O
(1b) 5-bromo-1H-pyrrole-2-carbonyl-[Bmp1 peptidyl-carrier protein] + FADH2 + bromide + O2 = 4,5-dibromo-1H-pyrrole-2-carbonyl-[Bmp1 peptidyl-carrier protein] + FAD + 2 H2O
(1c) 4,5-dibromo-1H-pyrrole-2-carbonyl-[Bmp1 peptidyl-carrier protein] + FADH2 + bromide + O2 = 3,4,5-tribromo-1H-pyrrole-2-carbonyl-[Bmp1 peptidyl-carrier protein] + FAD + 2 H2O
Other name(s): bmp2 (gene name)
Systematic name: 1H-pyrrole-2-carbonyl-[peptidyl-carrier protein]:FADH2 oxidoreductase (brominating)
Comments: The enzyme, characterized from marine bacteria of the Pseudoalteromonas genus, belongs to a family of FAD-dependent halogenases that act on acyl-carrier protein-tethered substrates. It catalyses three successive rounds of bromination. While the order has not been verified, it is believed to resemble that of EC 1.14.19.56, S-(1H-pyrrole-2-carbonyl)-[peptidyl-carrier protein] chlorinase, due to significant sequence homology. Reduced FAD is provided in situ by a dedicated reductase and diffuses into the active site, where it reacts with the oxygen and bromide ion, resulting in formation of a bromoamine intermediate on a catalytic lysine side chain, and the eventual transfer of the bromide to the substrate. The enzyme from Pseudoalteromonas luteoviolacea 2ta16 is specific for bromide and does not accept chloride.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Agarwal, V., El Gamal, A.A., Yamanaka, K., Poth, D., Kersten, R.D., Schorn, M., Allen, E.E. and Moore, B.S. Biosynthesis of polybrominated aromatic organic compounds by marine bacteria. Nat. Chem. Biol. 10 (2014) 640–647. [DOI] [PMID: 24974229]
[EC 1.14.19.57 created 2018]
 
 
EC 1.14.19.58
Accepted name: tryptophan 5-halogenase
Reaction: L-tryptophan + FADH2 + chloride + O2 + H+ = 5-chloro-L-tryptophan + FAD + 2 H2O
For diagram of chlorotryptophan biosynthesis, click here
Other name(s): pyrH (gene name)
Systematic name: L-tryptophan:FADH2 oxidoreductase (5-halogenating)
Comments: A flavin-dependent halogenase. The enzyme from the bacterium Streptomyces rugosporus catalyses halogenation of the C-5 position of tryptophan during the biosynthesis of the antibiotic compound pyrroindomycin B. It utilizes molecular oxygen to oxidize the FADH2 cofactor, giving C4a-hydroperoxyflavin, which then reacts with chloride to produce a hypochlorite ion. The latter reacts with an active site lysine to generate a chloramine, which chlorinates the substrate. cf. EC 1.14.19.59, tryptophan 6-halogenase and EC 1.14.19.9, tryptophan 7-halogenase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Zehner, S., Kotzsch, A., Bister, B., Sussmuth, R.D., Mendez, C., Salas, J.A. and van Pee, K.H. A regioselective tryptophan 5-halogenase is involved in pyrroindomycin biosynthesis in Streptomyces rugosporus LL-42D005. Chem. Biol. 12 (2005) 445–452. [DOI] [PMID: 15850981]
2.  Zhu, X., De Laurentis, W., Leang, K., Herrmann, J., Ihlefeld, K., van Pee, K.H. and Naismith, J.H. Structural insights into regioselectivity in the enzymatic chlorination of tryptophan. J. Mol. Biol. 391 (2009) 74–85. [DOI] [PMID: 19501593]
[EC 1.14.19.58 created 2018]
 
 
EC 1.14.19.59
Accepted name: tryptophan 6-halogenase
Reaction: (1) L-tryptophan + FADH2 + chloride + O2 + H+ = 6-chloro-L-tryptophan + FAD + 2 H2O
(2) D-tryptophan + FADH2 + chloride + O2 + H+ = 6-chloro-D-tryptophan + FAD + 2 H2O
For diagram of chlorotryptophan biosynthesis, click here
Other name(s): sttH (gene name); thdH (gene name)
Systematic name: L-tryptophan:FADH2 oxidoreductase (6-halogenating)
Comments: The enzyme is a flavin-dependent halogenase that has been described from several bacterial species. It utilizes molecular oxygen to oxidize the FADH2 cofactor, giving C4a-hydroperoxyflavin, which then reacts with chloride to produce a hypochlorite ion. The latter reacts with an active site lysine to generate a chloramine, which chlorinates the substrate. cf. EC 1.14.19.58, tryptophan 5-halogenase, and EC 1.14.19.9, tryptophan 7-halogenase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Zeng, J. and Zhan, J. Characterization of a tryptophan 6-halogenase from Streptomyces toxytricini. Biotechnol. Lett. 33 (2011) 1607–1613. [DOI] [PMID: 21424165]
2.  Milbredt, D., Patallo, E.P. and van Pee, K.H. A tryptophan 6-halogenase and an amidotransferase are involved in thienodolin biosynthesis. Chembiochem 15 (2014) 1011–1020. [DOI] [PMID: 24692213]
3.  Shepherd, S.A., Menon, B.R., Fisk, H., Struck, A.W., Levy, C., Leys, D. and Micklefield, J. A structure-guided switch in the regioselectivity of a tryptophan halogenase. Chembiochem 17 (2016) 821–824. [DOI] [PMID: 26840773]
[EC 1.14.19.59 created 2018]
 
 
EC 1.14.19.60
Accepted name: 7-chloro-L-tryptophan 6-halogenase
Reaction: 7-chloro-L-tryptophan + FADH2 + chloride + O2 + H+ = 6,7-dichloro-L-tryptophan + FAD + 2 H2O
For diagram of chlorotryptophan biosynthesis, click here
Other name(s): ktzR (gene name)
Systematic name: 7-chloro-L-tryptophan:FADH2 oxidoreductase (6-halogenating)
Comments: An FAD-dependent halogenase. The enzyme, characterized from the bacterium Kutzneria sp. 744, works in tandem with EC 1.14.19.9, tryptophan 7-halogenase, (ktzQ) to generate 6,7-dichloro-L-tryptophan, which is incorporated as a pyrroloindoline in the kutznerides family of natural products. It has a 120-fold preference for 7-chloro-L-tryptophan over L-tryptophan as substrate.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Heemstra, J.R., Jr. and Walsh, C.T. Tandem action of the O2- and FADH2-dependent halogenases KtzQ and KtzR produce 6,7-dichlorotryptophan for kutzneride assembly. J. Am. Chem. Soc. 130 (2008) 14024–14025. [DOI] [PMID: 18828589]
[EC 1.14.19.60 created 2018]
 
 
EC 1.14.19.61
Accepted name: dihydrorhizobitoxine desaturase
Reaction: dihydrorhizobitoxine + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = rhizobitoxine + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
Glossary: dihydrorhizobitoxine = (2S)-2-amino-4-[(2R)-2-amino-3-hydroxypropoxy]butanoate
rhizobitoxine = (2S,3E)-2-amino-4-[(2R)-2-amino-3-hydroxypropoxy]but-3-enoate
Other name(s): rtxC (gene name)
Systematic name: dihydrorhizobitoxine,ferredoxin:oxygen oxidoreductase (3,4 trans-dehydrogenating)
Comments: The enzyme, characterized from the bacterium Bradyrhizobium elkanii, catalyses the final step in the biosynthesis of the nodulation enhancer compound rhizobitoxine.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Yasuta, T., Okazaki, S., Mitsui, H., Yuhashi, K., Ezura, H. and Minamisawa, K. DNA sequence and mutational analysis of rhizobitoxine biosynthesis genes in Bradyrhizobium elkanii. Appl. Environ. Microbiol. 67 (2001) 4999–5009. [PMID: 11679318]
2.  Okazaki, S., Sugawara, M. and Minamisawa, K. Bradyrhizobium elkanii rtxC gene is required for expression of symbiotic phenotypes in the final step of rhizobitoxine biosynthesis. Appl. Environ. Microbiol. 70 (2004) 535–541. [PMID: 14711685]
[EC 1.14.19.61 created 2018]
 
 
EC 1.14.20.4
Accepted name: anthocyanidin synthase
Reaction: a (2R,3S,4S)-leucoanthocyanidin + 2-oxoglutarate + O2 = an anthocyanidin + succinate + CO2 + 2 H2O (overall reaction)
(1a) a (2R,3S,4S)-leucoanthocyanidin + 2-oxoglutarate + O2 = a (4S)- 2,3-dehydroflavan-3,4-diol + succinate + CO2 + H2O
(1b) a (4S)- 2,3-dehydroflavan-3,4-diol = an anthocyanidin + H2O
For diagram of anthocyanin biosynthesis, click here
Glossary: taxifolin = 3,4-dihydroquercitin
Other name(s): leucocyanidin oxygenase; leucocyanidin,2-oxoglutarate:oxygen oxidoreductase; ANS (gene name)
Systematic name: (2R,3S,4S)-leucoanthocyanidin,2-oxoglutarate:oxygen oxidoreductase
Comments: The enzyme requires Fe(II) and ascorbate. It is involved in the pathway by which many flowering plants make anthocyanin flower pigments (glycosylated anthocyandins). The enzyme hydroxylates the C-3 carbon, followed by a trans diaxial elimination, forming a C-2,C-3 enol. The product loses a second water molecule to form anthocyanidins. When assayed in vitro, non-enzymic epimerization of the product can lead to formation of dihydroflavanols. Thus when the substrate is leucocyanidin, a mixture of (+)-taxifolin and (+)-epitaxifolin are formed. The enzyme can also oxidize the formed (+)-taxifolin to quercetin (cf. EC 1.14.20.6, flavonol synthase) [2,3].
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, CAS registry number: 180984-01-4
References:
1.  Saito, K., Kobayashi, M., Gong, Z., Tanaka, Y. and Yamazaki, M. Direct evidence for anthocyanidin synthase as a 2-oxoglutarate-dependent oxygenase: molecular cloning and functional expression of cDNA from a red forma of Perilla frutescens. Plant J. 17 (1999) 181–190. [DOI] [PMID: 10074715]
2.  Turnbull, J.J., Sobey, W.J., Aplin, R.T., Hassan, A., Firmin, J.L., Schofield, C.J. and Prescott, A.G. Are anthocyanidins the immediate products of anthocyanidin synthase? Chem. Commun. (2000) 2473–2474.
3.  Wilmouth, R.C., Turnbull, J.J., Welford, R.W., Clifton, I.J., Prescott, A.G. and Schofield, C.J. Structure and mechanism of anthocyanidin synthase from Arabidopsis thaliana. Structure 10 (2002) 93–103. [DOI] [PMID: 11796114]
4.  Turnbull, J.J., Nagle, M.J., Seibel, J.F., Welford, R.W., Grant, G.H. and Schofield, C.J. The C-4 stereochemistry of leucocyanidin substrates for anthocyanidin synthase affects product selectivity. Bioorg. Med. Chem. Lett. 13 (2003) 3853–3857. [DOI] [PMID: 14552794]
5.  Wellmann, F., Griesser, M., Schwab, W., Martens, S., Eisenreich, W., Matern, U. and Lukacin, R. Anthocyanidin synthase from Gerbera hybrida catalyzes the conversion of (+)-catechin to cyanidin and a novel procyanidin. FEBS Lett. 580 (2006) 1642–1648. [DOI] [PMID: 16494872]
[EC 1.14.20.4 created 2001 as EC 1.14.11.19, transferred 2018 to EC 1.14.20.4]
 
 
EC 1.14.20.5
Accepted name: flavone synthase I
Reaction: a flavanone + 2-oxoglutarate + O2 = a flavone + succinate + CO2 + H2O
For diagram of flavonoid biosynthesis, click here and for diagram of the biosynthesis of naringenin derivatives, click here
Other name(s): FNSI (gene name)
Systematic name: flavanone,2-oxoglutarate:oxygen oxidoreductase (dehydrating)
Comments: The enzyme, which has been found in rice and in members of the Apiaceae (a plant family), is a member of the 2-oxoglutarate-dependent dioxygenases, and requires ascorbate and Fe2+ for full activity.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 138263-98-6
References:
1.  Martens, S., Forkmann, G., Matern, U. and Lukačin, R. Cloning of parsley flavone synthase I. Phytochemistry 58 (2001) 43–46. [DOI] [PMID: 11524111]
2.  Lukačin, R., Matern, U., Junghanns, K.T., Heskamp, M.L., Britsch, L., Forkmann, G. and Martens, S. Purification and antigenicity of flavone synthase I from irradiated parsley cells. Arch. Biochem. Biophys. 393 (2001) 177–183. [DOI] [PMID: 11516175]
3.  Martens, S., Forkmann, G., Britsch, L., Wellmann, F., Matern, U. and Lukačin, R. Divergent evolution of flavonoid 2-oxoglutarate-dependent dioxygenases in parsley. FEBS Lett. 544 (2003) 93–98. [DOI] [PMID: 12782296]
[EC 1.14.20.5 created 2004 as EC 1.14.11.22, transferred 2018 to EC 1.14.20.5]
 
 
EC 1.14.20.6
Accepted name: flavonol synthase
Reaction: a dihydroflavonol + 2-oxoglutarate + O2 = a flavonol + succinate + CO2 + H2O
For diagram of flavonoid biosynthesis, click here, for diagram of kaempferol biosynthesis, click here and for diagram of myricetin biosynthesis, click here
Other name(s): FLS (gene name)
Systematic name: dihydroflavonol,2-oxoglutarate:oxygen oxidoreductase
Comments: In addition to the desaturation of (2R,3R)-dihydroflavonols to flavonols, the enzyme from Citrus unshiu (satsuma mandarin) also has a non-specific activity that trans-hydroxylates the flavanones (2S)-naringenin and the unnatural (2R)-naringenin at C-3 to kaempferol and (2R,3R)-dihydrokaempferol, respectively [2]. Requires Fe2+.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 146359-76-4
References:
1.  Wellmann, F., Lukačin, R., Moriguchi, T., Britsch, L., Schiltz, E. and Matern, U. Functional expression and mutational analysis of flavonol synthase from Citrus unshiu. Eur. J. Biochem. 269 (2002) 4134–4142. [DOI] [PMID: 12180990]
2.  Lukačin, R., Wellmann, F., Britsch, L., Martens, S. and Matern, U. Flavonol synthase from Citrus unshiu is a bifunctional dioxygenase. Phytochemistry 62 (2003) 287–292. [DOI] [PMID: 12620339]
3.  Martens, S., Forkmann, G., Britsch, L., Wellmann, F., Matern, U. and Lukačin, R. Divergent evolution of flavonoid 2-oxoglutarate-dependent dioxygenases in parsley. FEBS Lett. 544 (2003) 93–98. [DOI] [PMID: 12782296]
4.  Turnbull, J.J., Nakajima, J., Welford, R.W., Yamazaki, M., Saito, K. and Schofield, C.J. Mechanistic studies on three 2-oxoglutarate-dependent oxygenases of flavonoid biosynthesis: anthocyanidin synthase, flavonol synthase, and flavanone 3β-hydroxylase. J. Biol. Chem. 279 (2004) 1206–1216. [DOI] [PMID: 14570878]
[EC 1.14.20.6 created 2004 as EC 1.14.11.23, transferred 2018 to EC 1.14.20.6]
 
 
EC 1.14.20.7
Accepted name: 2-oxoglutarate/L-arginine monooxygenase/decarboxylase (succinate-forming)
Reaction: L-arginine + 2-oxoglutarate + O2 = succinate + CO2 + guanidine + (S)-1-pyrroline-5-carboxylate + H2O (overall reaction)
(1a) L-arginine + 2-oxoglutarate + O2 = succinate + CO2 + 5-hydroxy-L-arginine
(1b) 5-hydroxy-L-arginine = guanidine + (S)-1-pyrroline-5-carboxylate + H2O
Other name(s): ethene-forming enzyme; ethylene-forming enzyme; EFE
Systematic name: L-arginine,2-oxoglutarate:oxygen oxidoreductase (succinate-forming)
Comments: This is one of two simultaneous reactions catalysed by the enzyme, which is responsible for ethylene production in bacteria of the Pseudomonas syringae group. In the other reaction [EC 1.13.12.19, 2-oxoglutarate dioxygenase (ethene-forming)] the enzyme catalyses the dioxygenation of 2-oxoglutarate forming ethene and three molecules of carbon dioxide.The enzyme catalyses two cycles of the ethene-forming reaction for each cycle of the succinate-forming reaction, so that the stoichiometry of the products ethene and succinate is 2:1.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Nagahama, K., Ogawa, T., Fujii, T., Tazaki, M., Tanase, S., Morino, Y. and Fukuda, H. Purification and properties of an ethylene-forming enzyme from Pseudomonas syringae pv. phaseolicola PK2. J. Gen. Microbiol. 137 (1991) 2281–2286. [DOI] [PMID: 1770346]
2.  Fukuda, H., Ogawa, T., Tazaki, M., Nagahama, K., Fujii, T., Tanase, S. and Morino, Y. Two reactions are simultaneously catalyzed by a single enzyme: the arginine-dependent simultaneous formation of two products, ethylene and succinate, from 2-oxoglutarate by an enzyme from Pseudomonas syringae. Biochem. Biophys. Res. Commun. 188 (1992) 483–489. [DOI] [PMID: 1445291]
3.  Fukuda, H., Ogawa, T., Ishihara, K., Fujii, T., Nagahama, K., Omata, T., Inoue, Y., Tanase, S. and Morino, Y. Molecular cloning in Escherichia coli, expression, and nucleotide sequence of the gene for the ethylene-forming enzyme of Pseudomonas syringae pv. phaseolicola PK2. Biochem. Biophys. Res. Commun. 188 (1992) 826–832. [DOI] [PMID: 1445325]
4.  Martinez, S., Fellner, M., Herr, C.Q., Ritchie, A., Hu, J. and Hausinger, R.P. Structures and mechanisms of the non-heme Fe(II)- and 2-oxoglutarate-dependent ethylene-forming enzyme: substrate binding creates a twist. J. Am. Chem. Soc. 139 (2017) 11980–11988. [DOI] [PMID: 28780854]
[EC 1.14.20.7 created 2011 as EC 1.14.11.34, transferred 2018 to EC 1.14.20.7]
 
 
EC 1.14.20.8
Accepted name: (–)-deoxypodophyllotoxin synthase
Reaction: (–)-yatein + 2-oxoglutarate + O2 = (–)-deoxypodophyllotoxin + succinate + CO2 + H2O
For diagram of podophyllotoxin biosynthesis, click here
Glossary: (–)-yatein = (3R,4R)-4-(1,3-benzodioxol-5-ylmethyl)-3-(3,4,5-trimethoxybenzyl)dihydrofuran-2(3H)-one
(–)-deoxypodophyllotoxin = (5R,5aR,8aR)-5-(3,4,5-trimethoxyphenyl)-5,8,8a,9-tetrahydrofuro[3′,4′:6,7]naphtho[2,3-d][1,3]dioxol-6(5a)-one
Other name(s): 2-ODD (gene name)
Systematic name: (–)-yatein,2-oxoglutarate:oxygen oxidoreductase (ring-forming)
Comments: The enzyme, characterized from the plant Sinopodophyllum hexandrum (mayapple), is involved in the biosynthetic pathway of podophyllotoxin, a non-alkaloid toxin lignan whose derivatives are important anticancer drugs. It catalyses the closure of the central six-membered ring in the aryltetralin scaffold.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Lau, W. and Sattely, E.S. Six enzymes from mayapple that complete the biosynthetic pathway to the etoposide aglycone. Science 349 (2015) 1224–1228. [DOI] [PMID: 26359402]
[EC 1.14.20.8 created 2016 as EC 1.14.11.50, transferred 2018 to EC 1.14.20.8]
 
 
EC 1.14.20.9
Accepted name: L-tyrosine isonitrile desaturase
Reaction: (2S)-3-(4-hydroxyphenyl)-2-isocyanopropanoate + 2-oxoglutarate + O2 = (2E)-3-(4-hydroxyphenyl)-2-isocyanoprop-2-enoate + succinate + CO2 + H2O
Glossary: (2S)-3-(4-hydroxyphenyl)-2-isocyanopropanoic acid = L-tyrosine isonitrile
paerucumarin = 6,7-dihydroxy-3-isocyanochromen-2-one
Other name(s): pvcB (gene name)
Systematic name: (2S)-3-(4-hydroxyphenyl)-2-isocyanopropanoate,2-oxoglutarate:oxygen oxidoreductase
Comments: The enzyme is a member of the Fe2+, 2-oxoglutarate-dependent oxygenases and requires Fe2+. It has been characterized from bacteria that form the isonitrile-functionalized compound paerucumarin. cf. EC 1.14.20.10, L-tyrosine isonitrile desaturase/decarboxylase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Clarke-Pearson, M.F. and Brady, S.F. Paerucumarin, a new metabolite produced by the pvc gene cluster from Pseudomonas aeruginosa. J. Bacteriol. 190 (2008) 6927–6930. [DOI] [PMID: 18689486]
2.  Drake, E.J. and Gulick, A.M. Three-dimensional structures of Pseudomonas aeruginosa PvcA and PvcB, two proteins involved in the synthesis of 2-isocyano-6,7-dihydroxycoumarin. J. Mol. Biol. 384 (2008) 193–205. [DOI] [PMID: 18824174]
3.  Zhu, J., Lippa, G.M., Gulick, A.M. and Tipton, P.A. Examining reaction specificity in PvcB, a source of diversity in isonitrile-containing natural products. Biochemistry 54 (2015) 2659–2669. [DOI] [PMID: 25866990]
[EC 1.14.20.9 created 2018]
 
 
EC 1.14.20.10
Accepted name: L-tyrosine isonitrile desaturase/decarboxylase
Reaction: (2S)-3-(4-hydroxyphenyl)-2-isocyanopropanoate + 2-oxoglutarate + O2 = 4-[(E)-2-isocyanoethenyl]phenol + succinate + 2 CO2 + H2O
Glossary: (2S)-3-(4-hydroxyphenyl)-2-isocyanopropanoic acid = L-tyrosine isonitrile
rhabduscin = N-[(2S,3S,4R,5S,6R)-4,5-dihydroxy-6-{4-[(E)-2-isocyanoethenyl]phenoxy}-2-methyloxan-3-yl]acetamide
Other name(s): pvcB (gene name)
Systematic name: (2S)-3-(4-hydroxyphenyl)-2-isocyanopropanoate,2-oxoglutarate:oxygen oxidoreductase (decarboxylating)
Comments: The enzyme, characterized from the bacterium Xenorhabdus nematophila, is involved in rhabduscin biosynthesis. The enzyme is a member of the Fe2+, 2-oxoglutarate-dependent oxygenases. It is similar to EC 1.14.20.9, L-tyrosine isonitrile desaturase. However, the latter does not catalyse a decarboxylation of the substrate.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Crawford, J.M., Portmann, C., Zhang, X., Roeffaers, M.B. and Clardy, J. Small molecule perimeter defense in entomopathogenic bacteria. Proc. Natl Acad. Sci. USA 109 (2012) 10821–10826. [DOI] [PMID: 22711807]
2.  Zhu, J., Lippa, G.M., Gulick, A.M. and Tipton, P.A. Examining reaction specificity in PvcB, a source of diversity in isonitrile-containing natural products. Biochemistry 54 (2015) 2659–2669. [DOI] [PMID: 25866990]
[EC 1.14.20.10 created 2018]
 
 
EC 1.14.20.11
Accepted name: 3-[(Z)-2-isocyanoethenyl]-1H-indole synthase
Reaction: (2S)-3-(1H-indol-3-yl)-2-isocyanopropanoate + 2-oxoglutarate + O2 = 3-[(Z)-2-isocyanoethenyl]-1H-indole + succinate + 2 CO2 + H2O
Glossary: (2S)-3-(1H-indol-3-yl)-2-isocyanopropanoate = L-tryptophan isonitrile
Other name(s): ambI3 (gene name); famH3 (gene name)
Systematic name: (2S)-3-(1H-indol-3-yl)-2-isocyanopropanoate,2-oxoglutarate:oxygen oxidoreductase (decarboxylating, 3-[(Z)-2-isocyanoethenyl]-1H-indole-forming)
Comments: The enzyme, characterized from the cyanobacterium Fischerella ambigua UTEX 1903, participates in the biosynthesis of hapalindole-type alkaloids. The enzyme catalyses an Fe2+, 2-oxoglutarate-dependent monooxygenation at C-3, which is followed by decarboxylation and dehydration, resulting in the generation of a cis C-C double bond. cf. EC 1.14.20.12, L-tryptophan isonitrile desaturase/decarboxylase (3-[(E)-2-isocyanoethenyl]-1H-indole-forming).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Hillwig, M.L., Zhu, Q. and Liu, X. Biosynthesis of ambiguine indole alkaloids in cyanobacterium Fischerella ambigua. ACS Chem. Biol. 9 (2014) 372–377. [DOI] [PMID: 24180436]
2.  Chang, W.C., Sanyal, D., Huang, J.L., Ittiamornkul, K., Zhu, Q. and Liu, X. In vitro stepwise reconstitution of amino acid derived vinyl isocyanide biosynthesis: detection of an elusive intermediate. Org. Lett. 19 (2017) 1208–1211. [DOI] [PMID: 28212039]
[EC 1.14.20.11 created 2018]
 
 
EC 1.14.20.12
Accepted name: 3-[(E)-2-isocyanoethenyl]-1H-indole synthase
Reaction: (2S)-3-(1H-indol-3-yl)-2-isocyanopropanoate + 2-oxoglutarate + O2 = 3-[(E)-2-isocyanoethenyl]-1H-indole + succinate + 2 CO2 + H2O
Glossary: (2S)-3-(1H-indol-3-yl)-2-isocyanopropanoate = L-tryptophan isonitrile
Other name(s): isnB (gene name)
Systematic name: (2S)-3-(1H-indol-3-yl)-2-isocyanopropanoate,2-oxoglutarate:oxygen oxidoreductase (decarboxylating, 3-[(E)-2-isocyanoethenyl]-1H-indole-forming)
Comments: The enzyme has been characterized from an unidentified soil bacterium. It catalyses an Fe2+, 2-oxoglutarate-dependent monooxygenation at C-3, which is followed by decarboxylation and dehydration, resulting in the generation of a trans C-C double bond. cf. EC 1.14.20.11, L-tryptophan isonitrile desaturase/decarboxylase (3-[(Z)-2-isocyanoethenyl]-1H-indole-forming).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Brady, S.F. and Clardy, J. Cloning and heterologous expression of isocyanide biosynthetic genes from environmental DNA. Angew Chem Int Ed Engl 44 (2005) 7063–7065. [PMID: 16206308]
2.  Chang, W.C., Sanyal, D., Huang, J.L., Ittiamornkul, K., Zhu, Q. and Liu, X. In vitro stepwise reconstitution of amino acid derived vinyl isocyanide biosynthesis: detection of an elusive intermediate. Org. Lett. 19 (2017) 1208–1211. [DOI] [PMID: 28212039]
[EC 1.14.20.12 created 2018]
 
 
EC 1.14.20.13
Accepted name: 6β-hydroxyhyoscyamine epoxidase
Reaction: (6S)-6β-hydroxyhyoscyamine + 2-oxoglutarate + O2 = scopolamine + succinate + CO2 + H2O
For diagram of tropane alkaloid biosynthesis, click here
Glossary: scopolamine = hyoscine = (1R,2R,4S,5S,7s)-9-methyl-3-oxa-9-azatricyclo[3.3.1.02,4]nonan-7-yl (2S)-3-hydroxy-2-phenylpropanoate
Other name(s): hydroxyhyoscyamine dioxygenase; (6S)-6-hydroxyhyoscyamine,2-oxoglutarate oxidoreductase (epoxide-forming)
Systematic name: (6S)-6β-hydroxyhyoscyamine,2-oxoglutarate:oxygen oxidoreductase (epoxide-forming)
Comments: Requires Fe2+ and ascorbate.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 121479-53-6
References:
1.  Hashimoto, T., Kohno, J. and Yamada, Y. 6β-Hydroxyhyoscyamine epoxidase from cultured roots of Hyoscyamus niger. Phytochemistry 28 (1989) 1077–1082.
[EC 1.14.20.13 created 1992 as EC 1.14.11.14, transferred 2018 to EC 1.14.20.13]
 
 
EC 1.14.99.60
Accepted name: 3-demethoxyubiquinol 3-hydroxylase
Reaction: 6-methoxy-3-methyl-2-(all-trans-polyprenyl)-1,4-benzoquinol + a reduced acceptor + O2 = 3-demethylubiquinol + acceptor + H2O
Glossary: 3-demethylubiquinol = 3-methoxy-6-methyl-5-(all trans-polyprenyl)benzene-1,2,4-triol
Other name(s): 6-methoxy-3-methyl-2-(all-trans-polyprenyl)-1,4-benzoquinol 5-hydroxylase; COQ7 (gene name); clk-1 (gene name); ubiF (gene name)
Systematic name: 6-methoxy-3-methyl-2-(all-trans-polyprenyl)-1,4-benzoquinol,acceptor:oxygen oxidoreductase (5-hydroxylating)
Comments: The enzyme catalyses the last hydroxylation reaction during the biosynthesis of ubiquinone.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Marbois, B.N. and Clarke, C.F. The COQ7 gene encodes a protein in Saccharomyces cerevisiae necessary for ubiquinone biosynthesis. J. Biol. Chem. 271 (1996) 2995–3004. [PMID: 8621692]
2.  Vajo, Z., King, L.M., Jonassen, T., Wilkin, D.J., Ho, N., Munnich, A., Clarke, C.F. and Francomano, C.A. Conservation of the Caenorhabditis elegans timing gene clk-1 from yeast to human: a gene required for ubiquinone biosynthesis with potential implications for aging. Mamm Genome 10 (1999) 1000–1004. [PMID: 10501970]
3.  Kwon, O., Kotsakis, A. and Meganathan, R. Ubiquinone (coenzyme Q) biosynthesis in Escherichia coli: identification of the ubiF gene. FEMS Microbiol. Lett. 186 (2000) 157–161. [PMID: 10802164]
4.  Stenmark, P., Grunler, J., Mattsson, J., Sindelar, P.J., Nordlund, P. and Berthold, D.A. A new member of the family of di-iron carboxylate proteins. Coq7 (clk-1), a membrane-bound hydroxylase involved in ubiquinone biosynthesis. J. Biol. Chem. 276 (2001) 33297–33300. [PMID: 11435415]
5.  Tran, U.C., Marbois, B., Gin, P., Gulmezian, M., Jonassen, T. and Clarke, C.F. Complementation of Saccharomyces cerevisiae coq7 mutants by mitochondrial targeting of the Escherichia coli UbiF polypeptide: two functions of yeast Coq7 polypeptide in coenzyme Q biosynthesis. J. Biol. Chem. 281 (2006) 16401–16409. [PMID: 16624818]
[EC 1.14.99.60 created 2018]
 
 
*EC 1.18.6.1
Accepted name: nitrogenase
Reaction: 8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O = 8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
For diagram of reaction, click here
Other name(s): reduced ferredoxin:dinitrogen oxidoreductase (ATP-hydrolysing)
Systematic name: ferredoxin:dinitrogen oxidoreductase (ATP-hydrolysing, molybdenum-dependent)
Comments: Requires Mg2+. The enzyme is a complex of two components (namely dinitrogen reductase and dinitrogenase). Dinitrogen reductase is a [4Fe-4S] protein, which, in the presence of two molecules of ATP, transfers an electron from ferredoxin to the dinitrogenase component. Dinitrogenase is a molybdenum-iron protein that reduces dinitrogen to two molecules of ammonia in three successive two-electron reductions via diazene and hydrazine. The reduction is initiated by formation of hydrogen in stoichiometric amounts [2]. Acetylene is reduced to ethylene (but only very slowly to ethane), azide to nitrogen and ammonia, and cyanide to methane and ammonia. In the absence of a suitable substrate, hydrogen is slowly formed. Ferredoxin may be replaced by flavodoxin [see EC 1.19.6.1 nitrogenase (flavodoxin)]. The enzyme does not reduce CO (cf. EC 1.18.6.2, vanadium-dependent nitrogenase).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, UM-BBD, CAS registry number: 9013-04-1
References:
1.  Zumft, W.G., Paneque, A., Aparicio, P.J. and Losada, M. Mechanism of nitrate reduction in Chlorella. Biochem. Biophys. Res. Commun. 36 (1969) 980–986. [DOI] [PMID: 4390523]
2.  Liang, J. and Burris, R.H. Hydrogen burst associated with nitrogenase-catalyzed reactions. Proc. Natl. Acad. Sci. USA 85 (1988) 9446–9450. [DOI] [PMID: 3200830]
3.  Dance, I. The mechanism of nitrogenase. Computed details of the site and geometry of binding of alkyne and alkene substrates and intermediates. J. Am. Chem. Soc. 126 (2004) 11852–11863. [DOI] [PMID: 15382920]
4.  Chan, J.M., Wu, W., Dean, D.R. and Seefeldt, L.C. Construction and characterization of a heterodimeric iron protein: defining roles for adenosine triphosphate in nitrogenase catalysis. Biochemistry 39 (2000) 7221–7228. [DOI] [PMID: 10852721]
[EC 1.18.6.1 created 1978 as EC 1.18.2.1, transferred 1984 to EC 1.18.6.1, modified 2005, modified 2018]
 
 
EC 1.18.6.2
Accepted name: vanadium-dependent nitrogenase
Reaction: 12 reduced ferredoxin + 12 H+ + N2 + 40 ATP + 40 H2O = 12 oxidized ferredoxin + 3 H2 + 2 NH3 + 40 ADP + 40 phosphate
Other name(s): vnfD (gene name); vnfG (gene name); vnfK (gene name)
Systematic name: ferredoxin:dinitrogen oxidoreductase (ATP-hydrolysing, vanadium-dependent)
Comments: Requires Mg2+. This enzyme, originally isolated from the bacterium Azotobacter vinelandii, is a complex of two components (namely dinitrogen reductase and dinitrogenase). Dinitrogen reductase is a [4Fe-4S] protein, which, in the presence of ATP, transfers an electron from ferredoxin to the dinitrogenase component. Dinitrogenase is a vanadium-iron protein that reduces dinitrogen to two molecules of ammonia in three successive two-electron reductions via diazine and hydrazine. Compared with molybdenum-depedent nitrogenase (EC 1.18.6.1), this enzyme produces more dihydrogen and consumes more ATP per dinitrogen molecule being reduced. Unlike EC 1.18.6.1, this enzyme can also use CO as substrate, producing ethene, ethane and propane [7,9].
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, UM-BBD
References:
1.  Eady, R.R., Richardson, T.H., Miller, R.W., Hawkins, M. and Lowe, D.J. The vanadium nitrogenase of Azotobacter chroococcum. Purification and properties of the Fe protein. Biochem. J. 256 (1988) 189–196. [PMID: 2851977]
2.  Miller, R.W. and Eady, R.R. Molybdenum and vanadium nitrogenases of Azotobacter chroococcum. Low temperature favours N2 reduction by vanadium nitrogenase. Biochem. J. 256 (1988) 429–432. [PMID: 3223922]
3.  Thorneley, R.N., Bergstrom, N.H., Eady, R.R. and Lowe, D.J. Vanadium nitrogenase of Azotobacter chroococcum. MgATP-dependent electron transfer within the protein complex. Biochem. J. 257 (1989) 789–794. [PMID: 2784670]
4.  Dilworth, M.J., Eldridge, M.E. and Eady, R.R. Correction for creatine interference with the direct indophenol measurement of NH3 in steady-state nitrogenase assays. Anal. Biochem. 207 (1992) 6–10. [PMID: 1336937]
5.  Dilworth, M.J., Eldridge, M.E. and Eady, R.R. The molybdenum and vanadium nitrogenases of Azotobacter chroococcum: effect of elevated temperature on N2 reduction. Biochem. J. 289 (1993) 395–400. [PMID: 8424785]
6.  Eady, R.R. Current status of structure function relationships of vanadium nitrogenase. Coordinat. Chem. Rev. 237 (2003) 23–30.
7.  Lee, C.C., Hu, Y. and Ribbe, M.W. Vanadium nitrogenase reduces CO. Science 329:642 (2010). [DOI] [PMID: 20689010]
8.  Lee, C.C., Hu, Y. and Ribbe, M.W. Tracing the hydrogen source of hydrocarbons formed by vanadium nitrogenase. Angew Chem Int Ed Engl 50 (2011) 5545–5547. [DOI] [PMID: 21538750]
9.  Sippel, D. and Einsle, O. The structure of vanadium nitrogenase reveals an unusual bridging ligand. Nat. Chem. Biol. 13 (2017) 956–960. [DOI] [PMID: 28692069]
[EC 1.18.6.2 created 2018]
 
 
EC 2.1.1.348
Accepted name: mRNA m6A methyltransferase
Reaction: S-adenosyl-L-methionine + adenine in mRNA = S-adenosyl-L-homocysteine + N6-methyladenine in mRNA
Other name(s): METTL3 (gene name); METTL14 (gene name)
Systematic name: S-adenosyl-L-methionine:adenine in mRNA methyltransferase
Comments: This enzyme, found in eukaryotes, methylates adenines in mRNA with the consensus sequence RRACH.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Liu, J., Yue, Y., Han, D., Wang, X., Fu, Y., Zhang, L., Jia, G., Yu, M., Lu, Z., Deng, X., Dai, Q., Chen, W. and He, C. A METTL3-METTL14 complex mediates mammalian nuclear RNA N6-adenosine methylation. Nat. Chem. Biol. 10 (2014) 93–95. [DOI] [PMID: 24316715]
2.  Wang, X., Huang, J., Zou, T. and Yin, P. Human m6A writers: Two subunits, 2 roles. RNA Biol. 14 (2017) 300–304. [DOI] [PMID: 28121234]
[EC 2.1.1.348 created 2018]
 
 
*EC 2.3.1.74
Accepted name: chalcone synthase
Reaction: 3 malonyl-CoA + 4-coumaroyl-CoA = 4 CoA + naringenin chalcone + 3 CO2
For diagram of chalcone and stilbene biosynthesis, click here
Glossary: phloretin = 3-(4-hydroxyphenyl)-1-(2,4,6-trihydroxyphenyl)propan-1-one
Other name(s): naringenin-chalcone synthase; flavanone synthase; 6′-deoxychalcone synthase; chalcone synthetase; DOCS; CHS
Systematic name: malonyl-CoA:4-coumaroyl-CoA malonyltransferase (cyclizing)
Comments: The enzyme catalyses the first committed step in the biosynthesis of flavonoids. It can also act on dihydro-4-coumaroyl-CoA, forming phloretin.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, CAS registry number: 56803-04-4
References:
1.  Ayabe, S.-I., Udagawa, A. and Furuya, T. NAD(P)H-dependent 6′-deoxychalcone synthase activity in Glycyrrhiza echinata cells induced by yeast extract. Arch. Biochem. Biophys. 261 (1988) 458–462. [DOI] [PMID: 3355160]
2.  Heller, W. and Hahlbrock, K. Highly purified "flavanone synthase" from parsley catalyzes the formation of naringenin chalcone. Arch. Biochem. Biophys. 200 (1980) 617–619. [DOI] [PMID: 7436427]
3.  Yahyaa, M., Ali, S., Davidovich-Rikanati, R., Ibdah, M., Shachtier, A., Eyal, Y., Lewinsohn, E. and Ibdah, M. Characterization of three chalcone synthase-like genes from apple (Malus x domestica Borkh.). Phytochemistry 140 (2017) 125–133. [DOI] [PMID: 28482241]
[EC 2.3.1.74 created 1984, modified 2018]
 
 
*EC 2.3.1.97
Accepted name: glycylpeptide N-tetradecanoyltransferase
Reaction: tetradecanoyl-CoA + an N-terminal-glycyl-[protein] = CoA + an N-terminal-N-tetradecanoylglycyl-[protein]
Glossary: tetradecanoyl-CoA = myristoyl-CoA
Other name(s): NMT (gene name); peptide N-myristoyltransferase; myristoyl-CoA-protein N-myristoyltransferase; myristoyl-coenzyme A:protein N-myristoyl transferase; myristoylating enzymes; protein N-myristoyltransferase; tetradecanoyl-CoA:glycylpeptide N-tetradecanoyltransferase
Systematic name: tetradecanoyl-CoA:N-terminal-glycine-[protein] N-tetradecanoyltransferase
Comments: The enzyme catalyses the transfer of myristic acid from myristoyl-CoA to the amino group of the N-terminal glycine residue in a variety of eukaryotic proteins. It uses an ordered Bi Bi reaction in which myristoyl-CoA binds to the enzyme prior to the binding of the peptide substrate, and CoA release precedes the release of the myristoylated peptide. The enzyme from yeast is profoundly affected by amino acids further from the N-terminus, and is particularly stimulated by a serine residue at position 5.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, CAS registry number: 110071-61-9
References:
1.  Guertin, D., Gris-Miron, L. and Riendeau, D. Identification of a 51-kilodalton polypeptide fatty acyl chain acceptor in soluble extracts from mouse cardiac tissue. Biochem. Cell Biol. 64 (1986) 1249–1255. [PMID: 3566958]
2.  Heuckeroth, R.O., Towler, D.A., Adams, S.P., Glaser, L. and Gordon, J.I. 11-(Ethylthio)undecanoic acid. A myristic acid analogue of altered hydrophobicity which is functional for peptide N-myristoylation with wheat germ and yeast acyltransferase. J. Biol. Chem. 263 (1988) 2127–2133. [PMID: 3123489]
3.  Towler, D.A., Adams, S.P., Eubanks, S.R., Towery, D.S., Jackson-Machelski, E., Glaser, L. and Gordon, J.I. Purification and characterization of yeast myristoyl CoA:protein N-myristoyltransferase. Proc. Natl Acad. Sci. USA 84 (1987) 2708–2712. [PMID: 3106975]
4.  McIlhinney, R.A., Young, K., Egerton, M., Camble, R., White, A. and Soloviev, M. Characterization of human and rat brain myristoyl-CoA:protein N-myristoyltransferase: evidence for an alternative splice variant of the enzyme. Biochem. J. 333 (1998) 491–495. [PMID: 9677304]
5.  Farazi, T.A., Waksman, G. and Gordon, J.I. Structures of Saccharomyces cerevisiae N-myristoyltransferase with bound myristoylCoA and peptide provide insights about substrate recognition and catalysis. Biochemistry 40 (2001) 6335–6343. [PMID: 11371195]
[EC 2.3.1.97 created 1989, modified 1990, modified 2018]
 
 
EC 2.3.1.269
Accepted name: apolipoprotein N-acyltransferase
Reaction: a phosphoglycerolipid + an [apolipoprotein]-S-1,2-diacyl-sn-glyceryl-L-cysteine = a 1-lyso-phosphoglycerolipid + a [lipoprotein]-N-acyl-S-1,2-diacyl-sn-glyceryl-L-cysteine
Other name(s): lnt (gene name); Lnt
Systematic name: phosphoglyceride:[apolipoprotein]-S-1,2-diacyl-sn-glyceryl-L-cysteine N-acyltransferase
Comments: This bacterial enzyme transfers a fatty acid from a membrane phospholipid to form an amide linkage with the N-terminal cysteine residue of apolipoproteins, generating a triacylated molecule.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Gupta, S.D. and Wu, H.C. Identification and subcellular localization of apolipoprotein N-acyltransferase in Escherichia coli. FEMS Microbiol. Lett. 62 (1991) 37–41. [PMID: 2032623]
2.  Robichon, C., Vidal-Ingigliardi, D. and Pugsley, A.P. Depletion of apolipoprotein N-acyltransferase causes mislocalization of outer membrane lipoproteins in Escherichia coli. J. Biol. Chem. 280 (2005) 974–983. [PMID: 15513925]
3.  Hillmann, F., Argentini, M. and Buddelmeijer, N. Kinetics and phospholipid specificity of apolipoprotein N-acyltransferase. J. Biol. Chem. 286 (2011) 27936–27946. [DOI] [PMID: 21676878]
[EC 2.3.1.269 created 2018]
 
 
EC 2.3.1.270
Accepted name: lyso-ornithine lipid O-acyltransferase
Reaction: a lyso-ornithine lipid + an acyl-[acyl-carrier protein] = an ornithine lipid + a holo-[acyl-carrier protein]
Glossary: a lyso-ornithine lipid = an Nα-[(3R)-3-hydroxyacyl]-L-ornithine
an ornithine lipid = an Nα-[(3R)-3-(acyloxy)acyl]-L-ornithine
Other name(s): olsA (gene name)
Systematic name: Nα-[(3R)-hydroxy-acyl]-L-ornithine O-acyltransferase
Comments: This bacterial enzyme catalyses the second step in the formation of ornithine lipids.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Weissenmayer, B., Gao, J.L., Lopez-Lara, I.M. and Geiger, O. Identification of a gene required for the biosynthesis of ornithine-derived lipids. Mol. Microbiol. 45 (2002) 721–733. [PMID: 12139618]
2.  Aygun-Sunar, S., Bilaloglu, R., Goldfine, H. and Daldal, F. Rhodobacter capsulatus OlsA is a bifunctional enzyme active in both ornithine lipid and phosphatidic acid biosynthesis. J. Bacteriol. 189 (2007) 8564–8574. [PMID: 17921310]
3.  Lewenza, S., Falsafi, R., Bains, M., Rohs, P., Stupak, J., Sprott, G.D. and Hancock, R.E. The olsA gene mediates the synthesis of an ornithine lipid in Pseudomonas aeruginosa during growth under phosphate-limiting conditions, but is not involved in antimicrobial peptide susceptibility. FEMS Microbiol. Lett. 320 (2011) 95–102. [DOI] [PMID: 21535098]
[EC 2.3.1.270 created 2018]
 
 
EC 2.3.1.271
Accepted name: L-glutamate-5-semialdehyde N-acetyltransferase
Reaction: acetyl-CoA + L-glutamate-5-semialdehyde = CoA + N-acetyl-L-glutamate 5-semialdehyde
Other name(s): MPR1 (gene name); MPR2 (gene name)
Systematic name: acetyl-CoA:L-glutamate-5-semialdehyde N-acetyltransferase
Comments: The enzyme, characterized from the yeast Saccharomyces cerevisiae Σ1278b, N-acetylates L-glutamate-5-semialdehyde, an L-proline biosynthesis/utilization intermediate, into N-acetyl-L-glutamate 5-semialdehyde, an intermediate of L-arginine biosynthesis, under oxidative stress conditions. Its activity results in conversion of L-proline to L-arginine, and reduction in the concentration of L-glutamate 5-semialdehyde and its equilibrium partner, (S)-1-pyrroline-5-carboxylate, which has been linked to production of reactive oxygen species stress. The enzyme also acts on (S)-1-acetylazetidine-2-carboxylate, a toxic L-proline analog produced by some plants, resulting in its detoxification and conferring resistance on the yeast.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Shichiri, M., Hoshikawa, C., Nakamori, S. and Takagi, H. A novel acetyltransferase found in Saccharomyces cerevisiae Σ1278b that detoxifies a proline analogue, azetidine-2-carboxylic acid. J. Biol. Chem. 276 (2001) 41998–42002. [DOI] [PMID: 11555637]
2.  Nomura, M. and Takagi, H. Role of the yeast acetyltransferase Mpr1 in oxidative stress: regulation of oxygen reactive species caused by a toxic proline catabolism intermediate. Proc. Natl Acad. Sci. USA 101 (2004) 12616–12621. [PMID: 15308773]
3.  Nishimura, A., Kotani, T., Sasano, Y. and Takagi, H. An antioxidative mechanism mediated by the yeast N-acetyltransferase Mpr1: oxidative stress-induced arginine synthesis and its physiological role. FEMS Yeast Res. 10 (2010) 687–698. [DOI] [PMID: 20550582]
4.  Nishimura, A., Nasuno, R. and Takagi, H. The proline metabolism intermediate Δ1-pyrroline-5-carboxylate directly inhibits the mitochondrial respiration in budding yeast. FEBS Lett. 586 (2012) 2411–2416. [DOI] [PMID: 22698729]
5.  Nasuno, R., Hirano, Y., Itoh, T., Hakoshima, T., Hibi, T. and Takagi, H. Structural and functional analysis of the yeast N-acetyltransferase Mpr1 involved in oxidative stress tolerance via proline metabolism. Proc. Natl Acad. Sci. USA 110 (2013) 11821–11826. [DOI] [PMID: 23818613]
[EC 2.3.1.271 created 2018]
 
 
EC 2.3.1.272
Accepted name: 2-acetylphloroglucinol acetyltransferase
Reaction: 2 2-acetylphloroglucinol = 2,4-diacetylphloroglucinol + phloroglucinol
Glossary: phloroglucinol = benzene-1,3,5-triol
Other name(s): MAPG ATase
Systematic name: 2-acetylphloroglucinol C-acetyltransferase
Comments: The enzyme from the bacterium Pseudomonas sp. YGJ3 is composed of three subunits named PhlA, PhlB and PhlC. Production of 2,4-diacetylphloroglucinol, which has antibiotic activity, is strongly inhibited by chloride ions.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Hayashi, A., Saitou, H., Mori, T., Matano, I., Sugisaki, H. and Maruyama, K. Molecular and catalytic properties of monoacetylphloroglucinol acetyltransferase from Pseudomonas sp. YGJ3. Biosci. Biotechnol. Biochem. 76 (2012) 559–566. [DOI] [PMID: 22451400]
[EC 2.3.1.272 created 2018]
 
 
*EC 2.4.1.53
Accepted name: poly(ribitol-phosphate) β-glucosyltransferase
Reaction: n UDP-α-D-glucose + 4-O-[(1-D-ribitylphospho)n-(1-D-ribitylphospho)-(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol = n UDP + 4-O-[(2-β-D-glucosyl-1-D-ribitylphospho)n-(1-D-ribitylphospho)-(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol
Other name(s): TarQ; UDP glucose-poly(ribitol-phosphate) β-glucosyltransferase; uridine diphosphoglucose-poly(ribitol-phosphate) β-glucosyltransferase; UDP-D-glucose polyribitol phosphate glucosyl transferase; UDP-D-glucose:polyribitol phosphate glucosyl transferase; UDP-glucose:poly(ribitol-phosphate) β-D-glucosyltransferase
Systematic name: UDP-α-D-glucose:4-O-[(1-D-ribitylphospho)n-(1-D-ribitylphospho)-(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol β-D-glucosyltransferase (configuration-inverting)
Comments: Involved in the biosynthesis of poly ribitol phosphate teichoic acids in the cell wall of the bacterium Bacillus subtilis W23. This enzyme adds a β-D-glucose to the hydroxyl group at the 2 position of the ribitol phosphate units.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 37277-61-5
References:
1.  Chin, T., Burger, M.M. and Glaser, L. Synthesis of teichoic acids. VI. The formation of multiple wall polymers in Bacillus subtilis W-23. Arch. Biochem. Biophys. 116 (1966) 358–367. [PMID: 4960203]
2.  Brown, S., Xia, G., Luhachack, L.G., Campbell, J., Meredith, T.C., Chen, C., Winstel, V., Gekeler, C., Irazoqui, J.E., Peschel, A. and Walker, S. Methicillin resistance in Staphylococcus aureus requires glycosylated wall teichoic acids. Proc. Natl Acad. Sci. USA 109 (2012) 18909–18914. [DOI] [PMID: 23027967]
[EC 2.4.1.53 created 1972, modified 2018]
 
 
*EC 2.4.1.70
Accepted name: poly(ribitol-phosphate) α-N-acetylglucosaminyltransferase
Reaction: n UDP-N-acetyl-α-D-glucosamine + 4-O-(D-ribitylphospho)n-di[(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol = n UDP + 4-O-(2-N-acetyl-α-D-glucosaminyl-D-ribitylphospho)n-di[(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol
Other name(s): TarM; UDP acetylglucosamine-poly(ribitol phosphate) acetylglucosaminyltransferase (ambiguous); uridine diphosphoacetylglucosamine-poly(ribitol phosphate) acetylglucosaminyltransferase (ambiguous); UDP-N-acetyl-D-glucosamine:poly(ribitol-phosphate) N-acetyl-D-glucosaminyltransferase (ambiguous); UDP-N-acetyl-α-D-glucosamine:poly(ribitol-phosphate) N-acetyl-α-D-glucosaminyltransferase (ambiguous); poly(ribitol-phosphate) N-acetylglucosaminyltransferase (ambiguous)
Systematic name: UDP-N-acetyl-α-D-glucosamine:4-O-(D-ribitylphospho)n-di[(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol α-N-acetyl-D-glucosaminyltransferase (configuration-retaining)
Comments: Involved in the biosynthesis of poly(ribitol phosphate) teichoic acids in the cell wall of the bacterium Staphylococcus aureus. This enzyme adds an N-acetyl-α-D-glucosamine to the hydroxyl group at the 2 position of the ribitol phosphate units. cf. EC 2.4.1.355 [poly(ribitol-phosphate) β-N-acetylglucosaminyltransferase].
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 37277-71-7
References:
1.  Nathenson, S.G., Ishimoto, N. and Strominger, J.L. UDP-N-acetylglucosamine:polyribitol phosphate N-acetylglucosaminyltransferases from Staphylococcus aureus. Methods Enzymol. 8 (1966) 426–429.
2.  Xia, G., Maier, L., Sanchez-Carballo, P., Li, M., Otto, M., Holst, O. and Peschel, A. Glycosylation of wall teichoic acid in Staphylococcus aureus by TarM. J. Biol. Chem. 285 (2010) 13405–13415. [DOI] [PMID: 20185825]
3.  Sobhanifar, S., Worrall, L.J., Gruninger, R.J., Wasney, G.A., Blaukopf, M., Baumann, L., Lameignere, E., Solomonson, M., Brown, E.D., Withers, S.G. and Strynadka, N.C. Structure and mechanism of Staphylococcus aureus TarM, the wall teichoic acid α-glycosyltransferase. Proc. Natl Acad. Sci. USA 112 (2015) E576–E585. [DOI] [PMID: 25624472]
4.  Koc, C., Gerlach, D., Beck, S., Peschel, A., Xia, G. and Stehle, T. Structural and enzymatic analysis of TarM glycosyltransferase from Staphylococcus aureus reveals an oligomeric protein specific for the glycosylation of wall teichoic acid. J. Biol. Chem. 290 (2015) 9874–9885. [DOI] [PMID: 25697358]
[EC 2.4.1.70 created 1972, modified 2018]
 
 
EC 2.4.1.95
Deleted entry: bilirubin-glucuronoside glucuronosyltransferase
[EC 2.4.1.95 created 1978, deleted 2018]
 
 
*EC 2.4.1.101
Accepted name: α-1,3-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + Man5GlcNAc2-[protein] = UDP + Man5GlcNAc3-[protein]
For diagram of mannosyl-glycoprotein N-acetylglucosaminyltransferases, click here
Glossary: Man5GlcNAc2-[protein] = α-D-Man-(1→3)-[α-D-Man-(1→3)-[α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-N-Asn-[protein]
Man5GlcNAc3-[protein]= β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→3)-[α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-N-Asn-[protein]
Other name(s): MGAT1 (gene name); N-acetylglucosaminyltransferase I; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase I; uridine diphosphoacetylglucosamine-α-1,3-mannosylglycoprotein β-1,2-N-acetylglucosaminyltransferase; UDP-N-acetylglucosaminyl:α-1,3-D-mannoside-β-1,2-N-acetylglucosaminyltransferase I; UDP-N-acetylglucosaminyl:α-3-D-mannoside β-1,2-N-acetylglucosaminyltransferase I; α-1,3-mannosyl-glycoprotein β-1,2-N-acetylglucosaminyltransferase; GnTI; GlcNAc-T I; UDP-N-acetyl-D-glucosamine:3-(α-D-mannosyl)-β-D-mannosyl-glycoprotein 2-β-N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:α-D-mannosyl-(1→3)-β-D-mannosyl-glycoprotein 2-β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: The enzyme, found in plants and animals, participates in the processing of N-glycans in the Golgi apparatus. Its action is required before the other N-acetylglucosaminyltransferases involved in the process (GlcNAcT-II through VI) can act. While the natural substrate (produced by EC 3.2.1.113, mannosyl-oligosaccharide 1,2-α-mannosidase) is described here, the minimal substrate recognized by the enzyme is α-D-Man-(1→3)-β-D-Man-R.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, CAS registry number: 102576-81-8
References:
1.  Harpaz, N. and Schachter, H. Control of glycoprotein synthesis. Bovine colostrum UDP-N-acetylglucosamine:α-D-mannoside β2-N-acetylglucosaminyltransferase I. Separation from UDP-N-acetylglucosamine:α-D-mannoside β2-N-acetylglucosaminyltransferase II, partial purification, and substrate specificity. J. Biol. Chem. 255 (1980) 4885–4893. [PMID: 6445358]
2.  Mendicino, J., Chandrasekaran, E.V., Anumula, K.R. and Davila, M. Isolation and properties of α-D-mannose:β-1,2-N-acetylglucosaminyltransferase from trachea mucosa. Biochemistry 20 (1981) 967–976. [PMID: 6452163]
3.  Oppenheimer, C.L. and Hill, R.L. Purification and characterization of a rabbit liver α1→3 mannoside β1→2 N-acetylglucosaminyltransferase. J. Biol. Chem. 256 (1981) 799–804. [PMID: 6450208]
4.  Oppenheimer, C.L., Eckhardt, A.E. and Hill, R.L. The nonidentity of porcine N-acetylglucosaminyltransferases I and II. J. Biol. Chem. 256 (1981) 11477–11482. [PMID: 6457827]
5.  Miyagi, T. and Tsuiki, S. Studies on UDP-N-acetylglucosamine : α-mannoside β-N-acetylglucosaminyltransferase of rat liver and hepatomas. Biochim. Biophys. Acta 661 (1981) 148–157. [DOI] [PMID: 6170335]
6.  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]
7.  Vella, G.J., Paulsen, H. and Schachter, H. Control of glycoprotein synthesis. IX. A terminal Man alphal-3Man β1- sequence in the substrate is the minimum requirement for UDP-N-acetyl-D-glucosamine: α-D-mannoside (GlcNAc to Man α1-3) β2-N-acetylglucosaminyltransferase I. Can. J. Biochem. Cell Biol. 62 (1984) 409–417. [PMID: 6235906]
8.  Unligil, U.M., Zhou, S., Yuwaraj, S., Sarkar, M., Schachter, H. and Rini, J.M. X-ray crystal structure of rabbit N-acetylglucosaminyltransferase I: catalytic mechanism and a new protein superfamily. EMBO J. 19 (2000) 5269–5280. [DOI] [PMID: 11032794]
[EC 2.4.1.101 created 1983, modified 2001 (EC 2.4.1.51 created 1972, part incorporated 1984), modified 2018]
 
 
*EC 2.4.1.102
Accepted name: β-1,3-galactosyl-O-glycosyl-glycoprotein β-1,6-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + O3-[β-D-galactosyl-(1→3)-N-acetyl-α-D-galactosaminyl]-L-seryl/threonyl-[protein] = UDP + O3-{β-D-galactosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→6)]-N-acetyl-α-D-galactosaminyl}-L-seryl/threonyl-[protein]
Glossary: core 1 = O3-[β-D-galactosyl-(1→3)-N-acetyl-α-D-galactosaminyl]-L-seryl/threonyl-[protein]
core 2 = O3-{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 I; β6-N-acetylglucosaminyltransferase; uridine diphosphoacetylglucosamine-mucin β-(1→6)-acetylglucosaminyltransferase; core 2 acetylglucosaminyltransferase; core 6-β-GlcNAc-transferase A; UDP-N-acetyl-D-glucosamine:O-glycosyl-glycoprotein (N-acetyl-D-glucosamine to N-acetyl-D-galactosamine of β-D-galactosyl-1,3-N-acetyl-D-galactosaminyl-R) β-1,6-N-acetyl-D-glucosaminyltransferase; GCNT1; GCNT3; UDP-N-acetyl-D-glucosamine:O-glycosyl-glycoprotein (N-acetyl-D-glucosamine to N-acetyl-D-galactosamine of β-D-galactosyl-(1→3)-N-acetyl-D-galactosaminyl-R) 6-β-N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:O3-[β-D-galactosyl-(1→3)-N-acetyl-α-D-galactosaminyl]-glycoprotein 6-β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: The enzyme catalyses the addition of N-acetyl-α-D-glucosamine to the core 1 structure of O-glycans forming core 2.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, CAS registry number: 95978-15-7
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. [DOI] [PMID: 6226356]
2.  Williams, D., Longmore, G., Matta, K.L. and Schachter, H. Mucin synthesis. II. Substrate specificity and product identification studies on canine submaxillary gland UDP-GlcNAc:Gal β1-3GalNAc(GlcNAc→GalNAc) β6-N-acetylglucosaminyltransferase. J. Biol. Chem. 255 (1980) 11253–11261. [PMID: 6449508]
3.  Williams, D. and Schachter, H. Mucin synthesis. I. Detection in canine submaxillary glands of an N-acetylglucosaminyltransferase which acts on mucin substrates. J. Biol. Chem. 255 (1980) 11247–11252. [PMID: 6449507]
[EC 2.4.1.102 created 1983, modified 2018]
 
 
*EC 2.4.1.143
Accepted name: α-1,6-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein] = UDP + β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein]
For diagram of mannosyl-glycoprotein N-acetylglucosaminyltransferases, click here
Other name(s): MGAT2 (gene name); N-acetylglucosaminyltransferase II; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase II; acetylglucosaminyltransferase II; uridine diphosphoacetylglucosamine-mannoside α1→6-acetylglucosaminyltransferase; uridine diphosphoacetylglucosamine-α-1,6-mannosylglycoprotein β-1-2-N-acetylglucosaminyltransferase; uridine diphosphoacetylglucosamine-α-D-mannoside β1-2-acetylglucosaminyltransferase; UDP-GlcNAc:mannoside α1-6 acetylglucosaminyltransferase; α-1,6-mannosyl-glycoprotein β-1,2-N-acetylglucosaminyltransferase; GnTII; GlcNAc-T II; UDP-N-acetyl-D-glucosamine:6-(α-D-mannosyl)-β-D-mannosyl-glycoprotein 2-β-N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:α-D-mannosyl-(1→6)-β-D-mannosyl-glycoprotein 2-β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: The enzyme, found in plants and animals, participates in the processing of N-glycans in the Golgi apparatus. Its activity initiates the synthesis of the second antenna of di-antennary complex N-glycans. While the natural substrate (produced by EC 3.2.1.114, mannosyl-oligosaccharide 1,3-1,6-α-mannosidase) is described here, the minimal substrate recognized by the enzyme is α-D-Man-(1→6)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→3)]-β-D-Man-R.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 105913-04-0
References:
1.  Harpaz, N. and Schachter, H. Control of glycoprotein synthesis. Bovine colostrum UDP-N-acetylglucosamine:α-D-mannoside β2-N-acetylglucosaminyltransferase I. Separation from UDP-N-acetylglucosamine:α-D-mannoside β2-N-acetylglucosaminyltransferase II, partial purification, and substrate specificity. J. Biol. Chem. 255 (1980) 4885–4893. [PMID: 6445358]
2.  Mendicino, J., Chandrasekaran, E.V., Anumula, K.R. and Davila, M. Isolation and properties of α-D-mannose:β-1,2-N-acetylglucosaminyltransferase from trachea mucosa. Biochemistry 20 (1981) 967–976. [PMID: 6452163]
3.  Oppenheimer, C.L., Eckhardt, A.E. and Hill, R.L. The nonidentity of porcine N-acetylglucosaminyltransferases I and II. J. Biol. Chem. 256 (1981) 11477–11482. [PMID: 6457827]
4.  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]
5.  Bendiak, B. and Schachter, H. Control of glycoprotein synthesis. Kinetic mechanism, substrate specificity, and inhibition characteristics of UDP-N-acetylglucosamine:α-D-mannoside β-1-2 N-acetylglucosaminyltransferase II from rat liver. J. Biol. Chem. 262 (1987) 5784–5790. [PMID: 2952645]
6.  Bendiak, B. and Schacter, H. Control of glycoprotein synthesis. Purification of UDP-N-acetylglucosamine:α-D-mannoside β1-2 N-acetylglucosaminyltransferase II from rat liver. J. Biol. Chem. 262 (1987) 5775–5783. [PMID: 2952644]
7.  Tan, J., D'Agostaro, A.F., Bendiak, B., Reck, F., Sarkar, M., Squire, J.A., Leong, P. and Schachter, H. The human UDP-N-acetylglucosamine: α-6-D-mannoside-β-1,2- N-acetylglucosaminyltransferase II gene (MGAT2). Cloning of genomic DNA, localization to chromosome 14q21, expression in insect cells and purification of the recombinant protein. Eur. J. Biochem. 231 (1995) 317–328. [DOI] [PMID: 7635144]
[EC 2.4.1.143 created 1984, modified 2001 (EC 2.4.1.51 created 1972, part incorporated 1984), modified 2018]
 
 
*EC 2.4.1.144
Accepted name: β-1,4-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein] = UDP + β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-[β-D-GlcNAc-(1→4)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein]
For diagram of mannosyl-glycoprotein N-acetylglucosaminyltransferases, click here
Other name(s): N-acetylglucosaminyltransferase III; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase III; uridine diphosphoacetylglucosamine-glycopeptide β4-acetylglucosaminyltransferase III; β-1,4-mannosyl-glycoprotein β-1,4-N-acetylglucosaminyltransferase; GnTIII; GlcNAc-T III; MGAT3 (gene name); UDP-N-acetyl-D-glucosamine:β-D-mannosyl-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:β-D-mannosyl-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: The enzyme, found in vertebrates, participates in the processing of N-glycans in the Golgi apparatus. The residue added by the enzyme at position 4 of the β-linked mannose of the trimannosyl core of N-glycans is known as a bisecting GlcNAc. Unlike GlcNAc residues added to other positions, it is not extended or modified. In addition, its presence prevents the action of other branching enzymes involved in the process such as GlcNAc-T IV (EC 2.4.1.145) and GlcNAc-T V (EC 2.4.1.155), and thus increased activity of GlcNAc-T III leads to a decrease in highly branched N-glycan structures.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 83744-93-8
References:
1.  Narasimhan, S. Control of glycoprotein synthesis. UDP-GlcNAc:glycopeptide β4-N-acetylglucosaminyltransferase III, an enzyme in hen oviduct which adds GlcNAc in β1-4 linkage to the β-linked mannose of the trimannosyl core of N-glycosyl oligosaccharides. J. Biol. Chem. 257 (1982) 10235–10242. [PMID: 6213618]
2.  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]
3.  Brockhausen, I., Carver, J.P. and Schachter, H. Control of glycoprotein synthesis. The use of oligosaccharide substrates and HPLC to study the sequential pathway for N-acetylglucosaminyltransferases I, II, III, IV, V, and VI in the biosynthesis of highly branched N-glycans by hen oviduct membranes. Biochem. Cell Biol. 66 (1988) 1134–1151. [PMID: 2975180]
4.  Nishikawa, A., Ihara, Y., Hatakeyama, M., Kangawa, K. and Taniguchi, N. Purification, cDNA cloning, and expression of UDP-N-acetylglucosamine: β-D-mannoside β-1,4N-acetylglucosaminyltransferase III from rat kidney. J. Biol. Chem. 267 (1992) 18199–18204. [PMID: 1325461]
5.  Ihara, Y., Nishikawa, A., Tohma, T., Soejima, H., Niikawa, N. and Taniguchi, N. cDNA cloning, expression, and chromosomal localization of human N-acetylglucosaminyltransferase III (GnT-III). J. Biochem. 113 (1993) 692–698. [PMID: 8370666]
[EC 2.4.1.144 created 1984, modified 2001 (EC 2.4.1.51 created 1972, part incorporated 1984), modified 2018]
 
 
*EC 2.4.1.145
Accepted name: α-1,3-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein] = UDP + β-D-GlcNAc-(1→2)-[β-D-GlcNAc-(1→4)]-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein]
For diagram of mannosyl-glycoprotein N-acetylglucosaminyltransferases, click here
Other name(s): N-acetylglucosaminyltransferase IV; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase IV; β-acetylglucosaminyltransferase IV; uridine diphosphoacetylglucosamine-glycopeptide β4-acetylglucosaminyltransferase IV; α-1,3-mannosylglycoprotein β-1,4-N-acetylglucosaminyltransferase; GnTIV; UDP-N-acetyl-D-glucosamine:3-[2-(N-acetyl-β-D-glucosaminyl)-α-D-mannosyl]-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→3)-β-D-mannosyl-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: Requires Mn2+. The enzyme, found in vertebrates, participates in the processing of N-glycans in the Golgi apparatus. By adding a glucosaminyl residue to biantennary N-linked glycans, it enables the synthesis of tri- and tetra-antennary complexes.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 86498-16-0
References:
1.  Gleeson, P.A. and Schachter, H. Control of glycoprotein synthesis. J. Biol. Chem. 258 (1983) 6162–6173. [PMID: 6222042]
2.  Oguri, S., Minowa, M.T., Ihara, Y., Taniguchi, N., Ikenaga, H. and Takeuchi, M. Purification and characterization of UDP-N-acetylglucosamine: α1,3-D-mannoside β1,4-N-acetylglucosaminyltransferase (N-acetylglucosaminyltransferase-IV) from bovine small intestine. J. Biol. Chem. 272 (1997) 22721–22727. [DOI] [PMID: 9278430]
3.  Minowa, M.T., Oguri, S., Yoshida, A., Hara, T., Iwamatsu, A., Ikenaga, H. and Takeuchi, M. cDNA cloning and expression of bovine UDP-N-acetylglucosamine: α1, 3-D-mannoside β1,4-N-acetylglucosaminyltransferase IV. J. Biol. Chem. 273 (1998) 11556–11562. [DOI] [PMID: 9565571]
4.  Yoshida, A., Minowa, M.T., Takamatsu, S., Hara, T., Oguri, S., Ikenaga, H. and Takeuchi, M. Tissue specific expression and chromosomal mapping of a human UDP-N-acetylglucosamine: α1,3-d-mannoside β1, 4-N-acetylglucosaminyltransferase. Glycobiology 9 (1999) 303–310. [DOI] [PMID: 10024668]
5.  Yoshida, A., Minowa, M.T., Takamatsu, S., Hara, T., Ikenaga, H. and Takeuchi, M. A novel second isoenzyme of the human UDP-N-acetylglucosamine:α1,3-D-mannoside β1,4-N-acetylglucosaminyltransferase family: cDNA cloning, expression, and chromosomal assignment. Glycoconj. J. 15 (1998) 1115–1123. [PMID: 10372966]
6.  Takamatsu, S., Antonopoulos, A., Ohtsubo, K., Ditto, D., Chiba, Y., Le, D.T., Morris, H.R., Haslam, S.M., Dell, A., Marth, J.D. and Taniguchi, N. Physiological and glycomic characterization of N-acetylglucosaminyltransferase-IVa and -IVb double deficient mice. Glycobiology 20 (2010) 485–497. [DOI] [PMID: 20015870]
[EC 2.4.1.145 created 1984, modified 2001 (EC 2.4.1.51 created 1972, part incorporated 1984), modified 2018]
 
 
*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.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 87927-99-9
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. [DOI] [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 2.4.1.155
Accepted name: α-1,6-mannosyl-glycoprotein 6-β-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + β-D-GlcNAc-(1→2)-[β-D-GlcNAc-(1→4)]-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein] = UDP + β-D-GlcNAc-(1→2)-[β-D-GlcNAc-(1→4)]-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-[β-D-GlcNAc-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein]
For diagram of mannosyl-glycoprotein n-acetylglucosaminyltransferases, click here
Other name(s): MGAT5 (gene name); N-acetylglucosaminyltransferase V; α-mannoside β-1,6-N-acetylglucosaminyltransferase; uridine diphosphoacetylglucosamine-α-mannoside β1→6-acetylglucosaminyltransferase; UDP-N-acetylglucosamine:α-mannoside-β1,6 N-acetylglucosaminyltransferase; α-1,3(6)-mannosylglycoprotein β-1,6-N-acetylglucosaminyltransferase; GnTV; GlcNAc-T V; UDP-N-acetyl-D-glucosamine:6-[2-(N-acetyl-β-D-glucosaminyl)-α-D-mannosyl]-glycoprotein 6-β-N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→6)-β-D-mannosyl-glycoprotein 6-β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: Requires Mg2+. The enzyme, found in vertebrates, participates in the processing of N-glycans in the Golgi apparatus. It catalyses the addition of N-acetylglucosamine in β 1-6 linkage to the α-linked mannose of biantennary N-linked oligosaccharides, and thus enables the synthesis of tri- and tetra-antennary complexes.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 83588-90-3
References:
1.  Cummings, R.D., Trowbridge, I.S. and Kornfeld, S. A mouse lymphoma cell line resistant to the leukoagglutinating lectin from Phaseolus vulgaris is deficient in UDP-GlcNAc: α-D-mannoside β1,6 N-acetylglucosaminyltransferase. J. Biol. Chem. 257 (1982) 13421–13427. [PMID: 6216250]
2.  Hindsgaul, O., Tahir, S.H., Srivastava, O.P. and Pierce, M. The trisaccharide β-D-GlcpNAc-(1→2)-α-D-Manp-(1→6)-β-D-Manp, as its 8-methoxycarbonyloctyl glycoside, is an acceptor selective for N-acetylglucosaminyltransferase V. Carbohydr. Res. 173 (1988) 263–272. [DOI] [PMID: 2834054]
3.  Shoreibah, M.G., Hindsgaul, O. and Pierce, M. Purification and characterization of rat kidney UDP-N-acetylglucosamine: α-6-D-mannoside β-1,6-N-acetylglucosaminyltransferase. J. Biol. Chem. 267 (1992) 2920–2927. [PMID: 1531335]
4.  Gu, J., Nishikawa, A., Tsuruoka, N., Ohno, M., Yamaguchi, N., Kangawa, K. and Taniguchi, N. Purification and characterization of UDP-N-acetylglucosamine: α-6-D-mannoside β 1-6N-acetylglucosaminyltransferase (N-acetylglucosaminyltransferase V) from a human lung cancer cell line. J. Biochem. 113 (1993) 614–619. [PMID: 8393437]
5.  Park, C., Jin, U.H., Lee, Y.C., Cho, T.J. and Kim, C.H. Characterization of UDP-N-acetylglucosamine:α-6-D-mannoside β-1,6-N-acetylglucosaminyltransferase V from a human hepatoma cell line Hep3B. Arch. Biochem. Biophys. 367 (1999) 281–288. [PMID: 10395745]
6.  Saito, T., Miyoshi, E., Sasai, K., Nakano, N., Eguchi, H., Honke, K. and Taniguchi, N. A secreted type of β 1,6-N-acetylglucosaminyltransferase V (GnT-V) induces tumor angiogenesis without mediation of glycosylation: a novel function of GnT-V distinct from the original glycosyltransferase activity. J. Biol. Chem. 277 (2002) 17002–17008. [PMID: 11872751]
[EC 2.4.1.155 created 1986, modified 2001, modified 2018]
 
 
*EC 2.4.1.195 – private review period expired (03 September 2018) [Last modified: 2018-04-28 18:07:44]
Accepted name: N-hydroxythioamide S-β-glucosyltransferase
Reaction: (1) UDP-α-D-glucose + (Z)-2-phenyl-1-thioacetohydroximate = UDP + desulfoglucotropeolin
(2) UDP-α-D-glucose + an (E)-ω-(methylsulfanyl)alkyl-thiohydroximate = UDP + an aliphatic desulfoglucosinolate
(3) UDP-α-D-glucose + (E)-2-(1H-indol-3-yl)-1-thioacetohydroximate = UDP + desulfoglucobrassicin
For diagram of glucotropeolin biosynthesis, click here
Glossary: an aliphatic desulfoglucosinolate = an ω-(methylsulfanyl)alkylhydroximate S-glucoside
Other name(s): UGT74B1 (gene name); desulfoglucosinolate-uridine diphosphate glucosyltransferase; uridine diphosphoglucose-thiohydroximate glucosyltransferase; thiohydroximate β-D-glucosyltransferase; UDPG:thiohydroximate glucosyltransferase; thiohydroximate S-glucosyltransferase; thiohydroximate glucosyltransferase; UDP-glucose:thiohydroximate S-β-D-glucosyltransferase; UDP-glucose:N-hydroxy-2-phenylethanethioamide S-β-D-glucosyltransferase
Systematic name: UDP-α-D-glucose:N-hydroxy-2-phenylethanethioamide S-β-D-glucosyltransferase
Comments: The enzyme specifically glucosylates the thiohydroximate functional group. It is involved in the biosynthesis of glucosinolates in cruciferous plants, and acts on aliphatic, aromatic, and indolic substrates.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, MetaCyc, CAS registry number: 9068-14-8
References:
1.  Jain, J.C., Reed, D.W., Groot Wassink, J.W.D. and Underhill, E.W. A radioassay of enzymes catalyzing the glucosylation and sulfation steps of glucosinolate biosynthesis in Brassica species. Anal. Biochem. 178 (1989) 137–140. [DOI] [PMID: 2524977]
2.  Reed, D.W., Davin, L., Jain, J.C., Deluca, V., Nelson, L. and Underhill, E.W. Purification and properties of UDP-glucose:thiohydroximate glucosyltransferase from Brassica napus L. seedlings. Arch. Biochem. Biophys. 305 (1993) 526–532. [DOI] [PMID: 8373190]
3.  Marillia, E.F., MacPherson, J.M., Tsang, E.W., Van Audenhove, K., Keller, W.A. and GrootWassink, J.W. Molecular cloning of a Brassica napus thiohydroximate S-glucosyltransferase gene and its expression in Escherichia coli. Physiol. Plant 113 (2001) 176–184. [PMID: 12060294]
4.  Fahey, J.W., Zalcmann, A.T. and Talalay, P. The chemical diversity and distribution of glucosinolates and isothiocyanates among plants. Phytochemistry 56 (2001) 5–51. [DOI] [PMID: 11198818]
5.  Grubb, C.D., Zipp, B.J., Ludwig-Muller, J., Masuno, M.N., Molinski, T.F. and Abel, S. Arabidopsis glucosyltransferase UGT74B1 functions in glucosinolate biosynthesis and auxin homeostasis. Plant J. 40 (2004) 893–908. [DOI] [PMID: 15584955]
[EC 2.4.1.195 created 1992, modified 2006, modified 2018]
 
 
*EC 2.4.1.201
Accepted name: α-1,6-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + β-D-GlcNAc-(1→2)-[β-D-GlcNAc-(1→4)]-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-[β-D-GlcNAc-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein] = UDP + β-D-GlcNAc-(1→2)-[β-D-GlcNAc-(1→4)]-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-[β-D-GlcNAc-(1→4)]-[β-D-GlcNAc-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc-N-Asn-[protein]
For diagram of mannosyl-glycoprotein n-acetylglucosaminyltransferases, click here
Other name(s): MGAT4C (gene name); N-acetylglucosaminyltransferase VI; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase VI; uridine diphosphoacetylglucosamine-glycopeptide β-1→4-acetylglucosaminyltransferase VI; mannosyl-glycoprotein β-1,4-N-acetylglucosaminyltransferase; GnTVI; GlcNAc-T VI; UDP-N-acetyl-D-glucosamine:2,6-bis(N-acetyl-β-D-glucosaminyl)-α-D-mannosyl-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase
Systematic name: UDP-N-acetyl-α-D-glucosamine:N-acetyl-β-D-glucosaminyl-(1→6)-[N-acetyl-β-D-glucosaminyl-(1→2)]-α-D-mannosyl-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: Requires a high concentration of Mn2+ for maximal activity. The enzyme, characterized from hen oviduct membranes, participates in the processing of N-glycans in the Golgi apparatus. It transfers GlcNAc in β1-4 linkage to a D-mannose residue that already has GlcNAc residues attached at positions 2 and 6 by β linkages. No homologous enzyme appears to exist in mammals.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 119699-68-2
References:
1.  Brockhausen, I., Hull, E., Hindsgaul, O., Schachter, H., Shah, R.N., Michnick, S.W. and Carver, J.P. Control of glycoprotein synthesis. Detection and characterization of a novel branching enzyme from hen oviduct, UDP-N-acetylglucosamine:GlcNAc β1-6 (GlcNAc β1-2)Man α-R (GlcNAc to Man) β-4-N-acetylglucosaminyltransferase VI. J. Biol. Chem. 264 (1989) 11211–11221. [PMID: 2525556]
2.  Taguchi, T., Ogawa, T., Inoue, S., Inoue, Y., Sakamoto, Y., Korekane, H. and Taniguchi, N. Purification and characterization of UDP-GlcNAc:GlcNAcβ1-6(GlcNAcβ1-2)Manα1-R [GlcNAc to Man]-β1,4-N-acetylglucosaminyltransferase VI from hen oviduct. J. Biol. Chem. 275 (2000) 32598–32602. [DOI] [PMID: 10903319]
3.  Sakamoto, Y., Taguchi, T., Honke, K., Korekane, H., Watanabe, H., Tano, Y., Dohmae, N., Takio, K., Horii, A. and Taniguchi, N. Molecular cloning and expression of cDNA encoding chicken UDP-N-acetyl-D-glucosamine (GlcNAc): GlcNAcβ 1-6(GlcNAcβ 1-2)- manα 1-R[GlcNAc to man]β 1,4N-acetylglucosaminyltransferase VI. J. Biol. Chem. 275 (2000) 36029–36034. [DOI] [PMID: 10962001]
[EC 2.4.1.201 created 1992, modified 2001, modified 2018]
 
 
*EC 2.4.1.226
Accepted name: N-acetylgalactosaminyl-proteoglycan 3-β-glucuronosyltransferase
Reaction: (1) UDP-α-D-glucuronate + [protein]-3-O-(β-D-GalNAc-(1→4)-β-D-GlcA-(1→3)-β-D-Gal-(1→3)-β-D-Gal-(1→4)-β-D-Xyl)-L-serine = UDP + [protein]-3-O-(β-D-GlcA-(1→3)-β-D-GalNAc-(1→4)-β-D-GlcA-(1→3)-β-D-Gal-(1→3)-β-D-Gal-(1→4)-β-D-Xyl)-L-serine
(2) UDP-α-D-glucuronate + [protein]-3-O-([β-D-GalNAc-(1→4)-β-D-GlcA-(1→3)]n-β-D-GalNAc-(1→4)-β-D-GlcA-(1→3)-β-D-Gal-(1→3)-β-D-Gal-(1→4)-β-D-Xyl)-L-serine = UDP + [protein]-3-O-(β-D-GlcA-(1→3)-[β-D-GalNAc-(1→4)-β-D-GlcA-(1→3)]n-β-D-GalNAc-(1→4)-β-D-GlcA-(1→3)-β-D-Gal-(1→3)-β-D-Gal-(1→4)-β-D-Xyl)-L-serine
For diagram of chondroitin biosynthesis (later stages), click here
Other name(s): chondroitin glucuronyltransferase II; α-D-glucuronate:N-acetyl-β-D-galactosaminyl-(1→4)-β-D-glucuronosyl-proteoglycan 3-β-glucuronosyltransferase; UDP-α-D-glucuronate:N-acetyl-β-D-galactosaminyl-(1→4)-β-D-glucuronosyl-proteoglycan 3-β-glucuronosyltransferase
Systematic name: UDP-α-D-glucuronate:[protein]-3-O-(β-D-GalNAc-(1→4)-β-D-GlcA-(1→3)-β-D-Gal-(1→3)-β-D-Gal-(1→4)-β-D-Xyl)-L-serine = UDP + [protein]-3-O-(β-D-GlcA-(1→3)-β-D-GalNAc-(1→4)-β-D-GlcA-(1→3)-β-D-Gal-(1→3)-β-D-Gal-(1→4)-β-D-Xyl)-L-serine 3-β-glucuronosyltransferase (configuration-inverting)
Comments: Involved in the biosynthesis of chondroitin and dermatan sulfate. The human chondroitin synthetase is a bifunctional glycosyltransferase, which has the 3-β-glucuronosyltransferase and 4-β-N-acetylgalactosaminyltransferase (EC 2.4.1.175) activities required for the synthesis of the chondroitin sulfate disaccharide repeats. Similar chondroitin synthase ’co-polymerases’ can be found in Pasteurella multocida and Escherichia coli. There is also another human protein with apparently only the 3-β-glucuronosyltransferase activity.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 269077-98-7
References:
1.  Kitagawa, H., Uyama, T. and Sugahara, K. Molecular cloning and expression of a human chondroitin synthase. J. Biol. Chem. 276 (2001) 38721–38726. [DOI] [PMID: 11514575]
2.  DeAngelis, P.L. and Padgett-McCue, A.J. Identification and molecular cloning of a chondroitin synthase from Pasteurella multocida type F. J. Biol. Chem. 275 (2000) 24124–24129. [DOI] [PMID: 10818104]
3.  Ninomiya, T., Sugiura, N., Tawada, A., Sugimoto, K., Watanabe, H. and Kimata, K. Molecular cloning and characterization of chondroitin polymerase from Escherichia coli strain K4. J. Biol. Chem. 277 (2002) 21567–21575. [DOI] [PMID: 11943778]
4.  Gotoh, M., Yada, T., Sato, T., Akashima, T., Iwasaki, H., Mochizuki, H., Inaba, N., Togayachi, A., Kudo, T., Watanabe, H., Kimata, K. and Narimatsu, H. Molecular cloning and characterization of a novel chondroitin sulfate glucuronyltransferase which transfers glucuronic acid to N-acetylgalactosamine. J. Biol. Chem. 277 (2002) 38179–38188. [DOI] [PMID: 12145278]
[EC 2.4.1.226 created 2002, modified 2018]
 
 
EC 2.4.1.353
Accepted name: sordaricin 6-deoxyaltrosyltransferase
Reaction: GDP-6-deoxy-α-D-altrose + sordaricin = 4′-O-demethylsordarin + GDP
For diagram of sordarin biosynthesis, click here
Glossary: sordaricin = (1R,3aR,4S,4aR,7R,7aR,8aR)-4-formyl-8a-(hydroxymethyl)-7-methyl-3-(propan-2-yl)-1,3a,4,4a,5,6,7,7a,8,8-decahydro-1,4-methanocyclopenta[f]indene-3a-carboxylic acid
Other name(s): SdnJ
Systematic name: GDP-6-deoxy-α-D-altrose:sordaricin 6-deoxy-D-altrosyltransferase
Comments: The enzyme, isolated from the fungus Sordaria araneosa, is involved in the biosynthesis of the glycoside antibiotic sordarin.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Kudo, F., Matsuura, Y., Hayashi, T., Fukushima, M. and Eguchi, T. Genome mining of the sordarin biosynthetic gene cluster from Sordaria araneosa Cain ATCC 36386: characterization of cycloaraneosene synthase and GDP-6-deoxyaltrose transferase. J. Antibiot. (Tokyo) 69 (2016) 541–548. [DOI] [PMID: 27072286]
[EC 2.4.1.353 created 2018]
 
 
EC 2.4.1.354
Accepted name: (R)-mandelonitrile β-glucosyltransferase
Reaction: UDP-α-D-glucose + (R)-mandelonitrile = UDP + (R)-prunasin
Glossary: (R)-mandelonitrile = (2R)-hydroxy(phenyl)acetonitrile
(R)-prunasin = (2R)-(β-D-glucosyloxy)(phenyl)acetonitrile
Other name(s): UGT85A19 (gene name)
Systematic name: UDP-α-D-glucose:(R)-mandelonitrile β-D-glucosyltransferase (configuration-inverting)
Comments: The enzyme, characterized from Prunus dulcis (almond), is involved in the biosynthesis of the cyanogenic glycosides (R)-prunasin and (R)-amygdalin.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Franks, T. K., Yadollahi, A., Wirthensohn, M. G., Guerin, J. R., Kaiser, B. N., Sedgley, M. and Ford, C. M. A seed coat cyanohydrin glucosyltransferase is associated with bitterness in almond (Prunus dulcis) kernels. Funct. Plant Biol. 35 (2008) 236–246.
[EC 2.4.1.354 created 2018]
 
 
EC 2.4.1.355
Accepted name: poly(ribitol-phosphate) β-N-acetylglucosaminyltransferase
Reaction: n UDP-N-acetyl-α-D-glucosamine + 4-O-(D-ribitylphospho)n-di[(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol = n UDP + 4-O-(2-N-acetyl-β-D-glucosaminyl-D-ribitylphospho)n-di[(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol
Other name(s): TarS
Systematic name: UDP-N-acetyl-α-D-glucosamine:4-O-(D-ribitylphospho)n-di[(2R)-1-glycerophospho]-N-acetyl-β-D-mannosaminyl-(1→4)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol β-N-acetyl-D-glucosaminyltransferase (configuration-inverting)
Comments: Involved in the biosynthesis of poly(ribitol-phosphate) teichoic acids in the cell wall of the bacterium Staphylococcus aureus. This enzyme adds an N-acetyl-β-D-glucosamine to the OH group at the 2 position of the ribitol phosphate units. cf. EC 2.4.1.70 [poly(ribitol-phosphate) α-N-acetylglucosaminyltransferase].
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Nathenson, S. G., Strominger, J. L. Enzymatic synthesis of N-acetylglucosaminylribitol linkages in teichoic acid from Staphylococcus aureus, strain Copenhagen. J. Biol. Chem. 238 (1963) 3161–3169. [PMID: 14085356]
2.  Brown, S., Xia, G., Luhachack, L.G., Campbell, J., Meredith, T.C., Chen, C., Winstel, V., Gekeler, C., Irazoqui, J.E., Peschel, A. and Walker, S. Methicillin resistance in Staphylococcus aureus requires glycosylated wall teichoic acids. Proc. Natl Acad. Sci. USA 109 (2012) 18909–18914. [DOI] [PMID: 23027967]
3.  Sobhanifar, S., Worrall, L.J., King, D.T., Wasney, G.A., Baumann, L., Gale, R.T., Nosella, M., Brown, E.D., Withers, S.G. and Strynadka, N.C. Structure and mechanism of Staphylococcus aureus TarS, the wall teichoic acid β-glycosyltransferase involved in methicillin resistance. PLoS Pathog. 12:e1006067 (2016). [DOI] [PMID: 27973583]
[EC 2.4.1.355 created 2018]
 
 
EC 2.4.1.356
Accepted name: glucosyl-dolichyl phosphate glucuronosyltransferase
Reaction: UDP-α-D-glucuronate + an archaeal dolichyl β-D-glucosyl phosphate = UDP + an archaeal dolichyl β-D-glucuronosyl-(1→3)-β-D-glucosyl phosphate
Other name(s): aglG (gene name)
Systematic name: UDP-α-D-glucuronate:dolichyl phosphate glucuronosyltransferase (configuration-inverting)
Comments: The enzyme, characterized from the halophilic archaeon Haloferax volcanii, participates in the protein N-glycosylation pathway. Dolichol used by archaea is different from that used by eukaryotes. It is much shorter (C55-C60) and is α,ω-saturated. However, in vitro the enzyme was also able to act on a substrate with an unsaturated end.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Yurist-Doutsch, S., Abu-Qarn, M., Battaglia, F., Morris, H.R., Hitchen, P.G., Dell, A. and Eichler, J. aglF, aglG and aglI, novel members of a gene island involved in the N-glycosylation of the Haloferax volcanii S-layer glycoprotein. Mol. Microbiol. 69 (2008) 1234–1245. [DOI] [PMID: 18631242]
2.  Elharar, Y., Podilapu, A.R., Guan, Z., Kulkarni, S.S. and Eichler, J. Assembling glycan-charged dolichol phosphates: chemoenzymatic synthesis of a Haloferax volcanii N-glycosylation pathway intermediate. Bioconjug Chem 28 (2017) 2461–2470. [DOI] [PMID: 28809486]
[EC 2.4.1.356 created 2018]
 
 
EC 2.4.1.357
Accepted name: phlorizin synthase
Reaction: UDP-α-D-glucose + phloretin = UDP + phlorizin
For diagram of phloretin biosynthesis, click here
Glossary: phloretin = 3-(4-hydroxyphenyl)-1-(2,4,6-trihydroxyphenyl)propan-1-one
phlorizin = 3-(4-hydroxyphenyl)-1-[2-(β-D-glucopyranosyloxy)-4,6-dihydroxyphenyl]propan-1-one
Other name(s): MdPGT1: P2’GT
Systematic name: UDP-α-D-glucose:phloretin 2′-O-D-glucosyltransferase
Comments: Isolated from Malus X domestica (apple). Phlorizin inhibits sodium-linked glucose transporters. It gives the characteristic flavour of apples and cider.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Jugdé, H., Nguy, D., Moller, I., Cooney, J.M. and Atkinson, R.G. Isolation and characterization of a novel glycosyltransferase that converts phloretin to phlorizin, a potent antioxidant in apple. FEBS J. 275 (2008) 3804–3814. [DOI] [PMID: 18573104]
2.  Yahyaa, M., Davidovich-Rikanati, R., Eyal, Y., Sheachter, A., Marzouk, S., Lewinsohn, E. and Ibdah, M. Identification and characterization of UDP-glucose:Phloretin 4′-O-glycosyltransferase from Malus x domestica Borkh. Phytochemistry 130 (2016) 47–55. [DOI] [PMID: 27316677]
[EC 2.4.1.357 created 2018]
 
 
EC 2.4.2.59
Accepted name: sulfide-dependent adenosine diphosphate thiazole synthase
Reaction: NAD+ + glycine + sulfide = nicotinamide + ADP-5-ethyl-4-methylthiazole-2-carboxylate + 3 H2O
Other name(s): Thi4 (ambiguous)
Systematic name: NAD+:glycine ADP-D-ribosyltransferase (sulfide-adding)
Comments: This iron dependent enzyme, found in archaea, is involved in the biosynthesis of thiamine phosphate. The homologous enzyme from plants and fungi (EC 2.4.2.60, cysteine-dependent adenosine diphosphate thiazole synthase) uses an intrinsic cysteine as sulfur donor and, unlike the archaeal enzyme, is a single turn-over enzyme.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Zhang, X., Eser, B.E., Chanani, P.K., Begley, T.P. and Ealick, S.E. Structural basis for iron-mediated sulfur transfer in archael and yeast thiazole synthases. Biochemistry 55 (2016) 1826–1838. [DOI] [PMID: 26919468]
2.  Eser, B.E., Zhang, X., Chanani, P.K., Begley, T.P. and Ealick, S.E. From suicide enzyme to catalyst: the iron-dependent sulfide transfer in Methanococcus jannaschii thiamin thiazole biosynthesis. J. Am. Chem. Soc. 138 (2016) 3639–3642. [DOI] [PMID: 26928142]
[EC 2.4.2.59 created 2018]
 
 
EC 2.4.2.60
Accepted name: cysteine-dependent adenosine diphosphate thiazole synthase
Reaction: NAD+ + glycine + [ADP-thiazole synthase]-L-cysteine = nicotinamide + ADP-5-ethyl-4-methylthiazole-2-carboxylate + [ADP-thiazole synthase]-dehydroalanine + 3 H2O
Other name(s): THI4 (gene name) (ambiguous); THI1 (gene name); ADP-thiazole synthase
Systematic name: NAD+:glycine ADP-D-ribosyltransferase (dehydroalanine-producing)
Comments: This iron dependent enzyme, found in fungi and plants, is involved in the thiamine phosphate biosynthesis pathway. It is a single turn-over enzyme since the cysteine residue is not regenerated in vivo [3]. The homologous enzyme in archaea (EC 2.4.2.59, sulfide-dependent adenosine diphosphate thiazole synthase) uses sulfide as sulfur donor.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Godoi, P.H., Galhardo, R.S., Luche, D.D., Van Sluys, M.A., Menck, C.F. and Oliva, G. Structure of the thiazole biosynthetic enzyme THI1 from Arabidopsis thaliana. J. Biol. Chem. 281 (2006) 30957–30966. [DOI] [PMID: 16912043]
2.  Chatterjee, A., Abeydeera, N.D., Bale, S., Pai, P.J., Dorrestein, P.C., Russell, D.H., Ealick, S.E. and Begley, T.P. Saccharomyces cerevisiae THI4p is a suicide thiamine thiazole synthase. Nature 478 (2011) 542–546. [DOI] [PMID: 22031445]
3.  Zhang, X., Eser, B.E., Chanani, P.K., Begley, T.P. and Ealick, S.E. Structural basis for iron-mediated sulfur transfer in archael and yeast thiazole synthases. Biochemistry 55 (2016) 1826–1838. [DOI] [PMID: 26919468]
[EC 2.4.2.60 created 2018]
 
 
EC 2.5.1.143
Accepted name: pyridinium-3,5-biscarboxylic acid mononucleotide synthase
Reaction: deamido-NAD+ + hydrogencarbonate = AMP + pyridinium-3,5-biscarboxylate mononucleotide
Other name(s): LarB; P2CMN synthase; nicotinic acid adenine dinucleotide carboxylase/hydrolase; NaAD carboxylase/hydrolase
Systematic name: deamido-NAD+:hydrogencarbonate nicotinate-β-D-ribonucleotidyltransferase
Comments: This enzyme, found in the bacterium Lactobacillus plantarum, is involved in the biosynthesis of a nickel-pincer cofactor. It carboxylates the pyridinium ring of deamido-NAD+ and cleaves the phosphoanhydride bond to release AMP and generate pyridinium-3,5-biscarboxylic acid mononucleotide (P2CMN).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Desguin, B., Soumillion, P., Hols, P. and Hausinger, R.P. Nickel-pincer cofactor biosynthesis involves LarB-catalyzed pyridinium carboxylation and LarE-dependent sacrificial sulfur insertion. Proc. Natl Acad. Sci. USA 113 (2016) 5598–5603. [DOI] [PMID: 27114550]
[EC 2.5.1.143 created 2018]
 
 
EC 2.5.1.144
Accepted name: S-sulfo-L-cysteine synthase (O-acetyl-L-serine-dependent)
Reaction: O-acetyl-L-serine + thiosulfate = S-sulfo-L-cysteine + acetate
For diagram of O3-Acetyl-L-serine metabolism, click here
Glossary: O-acetyl-L-serine = (2S)-3-acetyloxy-2-aminopropanoic acid
Other name(s): cysteine synthase B; cysM (gene name); CS26 (gene name)
Systematic name: O-acetyl-L-serine:thiosulfate 2-amino-2-carboxyethyltransferase
Comments: In plants, the activity is catalysed by a chloroplastic enzyme that plays an important role in chloroplast function and is essential for light-dependent redox regulation within the chloroplast. The bacterial enzyme also catalyses the activity of EC 2.5.1.47, cysteine synthase. cf. EC 2.8.5.1, S-sulfo-L-cysteine synthase (3-phospho-L-serine-dependent).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB
References:
1.  Hensel, G. and Truper, H.G. O-Acetylserine sulfhydrylase and S-sulfocysteine synthase activities of Rhodospirillum tenue. Arch. Microbiol. 134 (1983) 227–232. [PMID: 6615127]
2.  Nakamura, T., Iwahashi, H. and Eguchi, Y. Enzymatic proof for the identity of the S-sulfocysteine synthase and cysteine synthase B of Salmonella typhimurium. J. Bacteriol. 158 (1984) 1122–1127. [PMID: 6373737]
3.  Bermudez, M.A., Paez-Ochoa, M.A., Gotor, C. and Romero, L.C. Arabidopsis S-sulfocysteine synthase activity is essential for chloroplast function and long-day light-dependent redox control. Plant Cell 22 (2010) 403–416. [DOI] [PMID: 20179139]
4.  Bermudez, M.A., Galmes, J., Moreno, I., Mullineaux, P.M., Gotor, C. and Romero, L.C. Photosynthetic adaptation to length of day is dependent on S-sulfocysteine synthase activity in the thylakoid lumen. Plant Physiol. 160 (2012) 274–288. [DOI] [PMID: 22829322]
5.  Gotor, C. and Romero, L.C. S-sulfocysteine synthase function in sensing chloroplast redox status. Plant Signal Behav 8:e23313 (2013). [DOI] [PMID: 23333972]
[EC 2.5.1.144 created 2018]
 
 
EC 2.5.1.145
Accepted name: phosphatidylglycerol—prolipoprotein diacylglyceryl transferase
Reaction: L-1-phosphatidyl-sn-glycerol + a [prolipoprotein]-L-cysteine = sn-glycerol 1-phosphate + an [prolipoprotein]-S-1,2-diacyl-sn-glyceryl-L-cysteine
Other name(s): lgt (gene name)
Systematic name: L-1-phosphatidyl-sn-glycerol:[prolipoprotein]-L-cysteine diacyl-sn-glyceryltransferase
Comments: This bacterial enzyme, which is associated with the membrane, catalyses the transfer of an sn-1,2-diacylglyceryl group from phosphatidylglycerol to the sulfhydryl group of the prospective N-terminal cysteine of a prolipoprotein, the first step in the formation of mature triacylated lipoproteins.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Sankaran, K. and Wu, H.C. Lipid modification of bacterial prolipoprotein. Transfer of diacylglyceryl moiety from phosphatidylglycerol. J. Biol. Chem. 269 (1994) 19701–19706. [PMID: 8051048]
2.  Qi, H.Y., Sankaran, K., Gan, K. and Wu, H.C. Structure-function relationship of bacterial prolipoprotein diacylglyceryl transferase: functionally significant conserved regions. J. Bacteriol. 177 (1995) 6820–6824. [PMID: 7592473]
3.  Gan, K., Sankaran, K., Williams, M.G., Aldea, M., Rudd, K.E., Kushner, S.R. and Wu, H.C. The umpA gene of Escherichia coli encodes phosphatidylglycerol:prolipoprotein diacylglyceryl transferase (lgt) and regulates thymidylate synthase levels through translational coupling. J. Bacteriol. 177 (1995) 1879–1882. [PMID: 7896715]
4.  Sankaran, K., Gan, K., Rash, B., Qi, H.Y., Wu, H.C. and Rick, P.D. Roles of histidine-103 and tyrosine-235 in the function of the prolipoprotein diacylglyceryl transferase of Escherichia coli. J. Bacteriol. 179 (1997) 2944–2948. [PMID: 9139912]
5.  Pailler, J., Aucher, W., Pires, M. and Buddelmeijer, N. Phosphatidylglycerol::prolipoprotein diacylglyceryl transferase (Lgt) of Escherichia coli has seven transmembrane segments, and its essential residues are embedded in the membrane. J. Bacteriol. 194 (2012) 2142–2151. [DOI] [PMID: 22287519]
[EC 2.5.1.145 created 2018]
 
 
EC 2.5.1.146
Accepted name: 3-geranyl-3-[(Z)-2-isocyanoethenyl]indole synthase
Reaction: geranyl diphosphate + 3-[(Z)-2-isocyanoethenyl]-1H-indole = 3-geranyl-3-[(Z)-2-isocyanoethenyl]-1H-indole + diphosphate
Other name(s): famD2 (gene name)
Systematic name: geranyl-diphosphate:3-[(Z)-2-isocyanoethenyl]-1H-indole geranyltransferase
Comments: The enzyme, characterized from the cyanobacterium Fischerella ambigua UTEX 1903, participates in the biosynthesis of hapalindole-type alkaloids.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Li, S., Lowell, A.N., Yu, F., Raveh, A., Newmister, S.A., Bair, N., Schaub, J.M., Williams, R.M. and Sherman, D.H. Hapalindole/ambiguine biogenesis Is mediated by a Cope rearrangement, C-C bond-forming cascade. J. Am. Chem. Soc. 137 (2015) 15366–15369. [DOI] [PMID: 26629885]
[EC 2.5.1.146 created 2018]
 
 
*EC 2.6.1.92
Accepted name: UDP-4-amino-4,6-dideoxy-N-acetyl-β-L-altrosamine transaminase
Reaction: UDP-4-amino-4,6-dideoxy-N-acetyl-β-L-altrosamine + 2-oxoglutarate = UDP-2-acetamido-2,6-dideoxy-β-L-arabino-hex-4-ulose + L-glutamate
Other name(s): PseC; UDP-4-amino-4,6-dideoxy-N-acetyl-β-L-altrosamine:2-oxoglutarate aminotransferase; UDP-β-L-threo-pentapyranos-4-ulose transaminase; UDP-4-dehydro-6-deoxy-D-glucose transaminase
Systematic name: UDP-4-amino-4,6-dideoxy-N-acetyl-β-L-altrosamine:2-oxoglutarate transaminase
Comments: A pyridoxal 5′-phosphate protein. The enzyme transfers the primary amino group of L-glutamate to C-4′′ of UDP-4-dehydro sugars, forming a C-N bond in a stereo configuration opposite to that of UDP. The enzyme from the bacterium Bacillus cereus has been shown to act on UDP-2-acetamido-2,6-dideoxy-β-L-arabino-hex-4-ulose, UDP-β-L-threo-pentapyranos-4-ulose, UDP-4-dehydro-6-deoxy-D-glucose, and UDP-2-acetamido-2,6-dideoxy-α-D-xylo-hex-4-ulose. cf. EC 2.6.1.34, UDP-N-acetylbacillosamine transaminase, which catalyses a similar reaction, but forms the C-N bond in the same stereo configuration as that of UDP.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Schoenhofen, I.C., McNally, D.J., Vinogradov, E., Whitfield, D., Young, N.M., Dick, S., Wakarchuk, W.W., Brisson, J.R. and Logan, S.M. Functional characterization of dehydratase/aminotransferase pairs from Helicobacter and Campylobacter: enzymes distinguishing the pseudaminic acid and bacillosamine biosynthetic pathways. J. Biol. Chem. 281 (2006) 723–732. [DOI] [PMID: 16286454]
2.  Schoenhofen, I.C., Lunin, V.V., Julien, J.P., Li, Y., Ajamian, E., Matte, A., Cygler, M., Brisson, J.R., Aubry, A., Logan, S.M., Bhatia, S., Wakarchuk, W.W. and Young, N.M. Structural and functional characterization of PseC, an aminotransferase involved in the biosynthesis of pseudaminic acid, an essential flagellar modification in Helicobacter pylori. J. Biol. Chem. 281 (2006) 8907–8916. [DOI] [PMID: 16421095]
3.  Mostafavi, A.Z. and Troutman, J.M. Biosynthetic assembly of the Bacteroides fragilis capsular polysaccharide A precursor bactoprenyl diphosphate-linked acetamido-4-amino-6-deoxygalactopyranose. Biochemistry 52 (2013) 1939–1949. [DOI] [PMID: 23458065]
4.  Hwang, S., Li, Z., Bar-Peled, Y., Aronov, A., Ericson, J. and Bar-Peled, M. The biosynthesis of UDP-D-FucNAc-4N-(2)-oxoglutarate (UDP-Yelosamine) in Bacillus cereus ATCC 14579: Pat and Pyl, an aminotransferase and an ATP-dependent Grasp protein that ligates 2-oxoglutarate to UDP-4-amino-sugars. J. Biol. Chem 289 (2014) 35620–35632. [DOI] [PMID: 25368324]
[EC 2.6.1.92 created 2011, modified 2018]
 
 
*EC 2.7.1.209
Accepted name: L-erythrulose 1-kinase
Reaction: ATP + L-erythrulose = ADP + L-erythrulose 1-phosphate
Other name(s): lerK (gene name); L-erythrulose 1-kinase [incorrect]
Systematic name: ATP:L-erythrulose 1-phosphotransferase
Comments: The enzyme, characterized from the bacterium Mycobacterium smegmatis, participates in the degradation of L-threitol.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Huang, H., Carter, M.S., Vetting, M.W., Al-Obaidi, N., Patskovsky, Y., Almo, S.C. and Gerlt, J.A. A general strategy for the discovery of metabolic pathways: D-threitol, L-threitol, and erythritol utilization in Mycobacterium smegmatis. J. Am. Chem. Soc. 137 (2015) 14570–14573. [DOI] [PMID: 26560079]
2.  Huang, H., Carter, M.S., Vetting, M.W., Al-Obaidi, N., Patskovsky, Y., Almo, S.C. and Gerlt, J.A. Correction to "A general strategy for the discovery of metabolic pathways: D-threitol, L-threitol, and erythritol utilization in Mycobacterium smegmatis". J. Am. Chem. Soc. 138:4267 (2016). [DOI] [PMID: 26978037]
[EC 2.7.1.209 created 2016, modified 2018]
 
 
EC 2.7.7.100
Accepted name: SAMP-activating enzyme
Reaction: ATP + [SAMP]-Gly-Gly = diphosphate + [SAMP]-Gly-Gly-AMP
Glossary: SAMP = small archaeal modifier protein = ubiquitin-like small archaeal modifier protein
Other name(s): UbaA (ambiguous); SAMP-activating enzyme E1 (ambiguous)
Systematic name: ATP:[SAMP]-Gly-Gly adenylyltransferase
Comments: Contains Zn2+. The enzyme catalyses the activation of SAMPs (Small Archaeal Modifier Proteins), which are ubiquitin-like proteins found only in the Archaea, by catalysing the ATP-dependent formation of a SAMP adenylate in which the C-terminal glycine of SAMP is bound to AMP via an acyl-phosphate linkage. The product of this activity can accept a sulfur atom to form a thiocarboxylate moiety that acts as a sulfur carrier involved in thiolation of tRNA and other metabolites such as molybdopterin. Alternatively, the enzyme can also catalyse the transfer of SAMP from its activated form to an internal cysteine residue, leading to a process termed SAMPylation (see EC 6.2.1.55, E1 SAMP-activating enzyme).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Miranda, H.V., Nembhard, N., Su, D., Hepowit, N., Krause, D.J., Pritz, J.R., Phillips, C., Soll, D. and Maupin-Furlow, J.A. E1- and ubiquitin-like proteins provide a direct link between protein conjugation and sulfur transfer in archaea. Proc. Natl Acad. Sci. USA 108 (2011) 4417–4422. [DOI] [PMID: 21368171]
2.  Maupin-Furlow, J.A. Ubiquitin-like proteins and their roles in archaea. Trends Microbiol 21 (2013) 31–38. [DOI] [PMID: 23140889]
3.  Hepowit, N.L., de Vera, I.M., Cao, S., Fu, X., Wu, Y., Uthandi, S., Chavarria, N.E., Englert, M., Su, D., Söll, D., Kojetin, D.J. and Maupin-Furlow, J.A. Mechanistic insight into protein modification and sulfur mobilization activities of noncanonical E1 and associated ubiquitin-like proteins of Archaea. FEBS J. 283 (2016) 3567–3586. [DOI] [PMID: 27459543]
[EC 2.7.7.100 created 2018]
 
 
*EC 2.8.1.8
Accepted name: lipoyl synthase
Reaction: [protein]-N6-(octanoyl)-L-lysine + an [Fe-S] cluster scaffold protein carrying a [4Fe-4S]2+ cluster + 2 S-adenosyl-L-methionine + 2 oxidized [2Fe-2S] ferredoxin + 6 H+ = [protein]-N6-[(R)-dihydrolipoyl]-L-lysine + an [Fe-S] cluster scaffold protein + 2 sulfide + 4 Fe3+ + 2 L-methionine + 2 5′-deoxyadenosine + 2 reduced [2Fe-2S] ferredoxin
Other name(s): lipA (gene name); LS; lipoate synthase; protein 6-N-(octanoyl)lysine:sulfur sulfurtransferase; protein N6-(octanoyl)lysine:sulfur sulfurtransferase; protein N6-(octanoyl)lysine:sulfur-(sulfur carrier) sulfurtransferase
Systematic name: [protein]-N6-(octanoyl)-L-lysine:an [Fe-S] cluster scaffold protein carrying a [4Fe-4S]2+ cluster sulfurtransferase
Comments: This enzyme catalyses the final step in the de-novo biosynthesis of the lipoyl cofactor, the attachment of two sulfhydryl groups to C6 and C8 of a pendant octanoyl chain. It is a member of the ‘AdoMet radical’ (radical SAM) family, all members of which produce the 5′-deoxyadenosin-5′-yl radical and methionine from AdoMet (S-adenosylmethionine) by the addition of an electron from an iron-sulfur centre. The enzyme contains two [4Fe-4S] clusters. The first cluster produces the radicals, which are converted into 5′-deoxyadenosine when they abstract hydrogen atoms from C6 and C8, respectively, leaving reactive radicals at these positions that interact with sulfur atoms within the second (auxiliary) cluster. Having donated two sulfur atoms, the auxiliary cluster is degraded during catalysis, but is regenerated immediately by the transfer of a new cluster from iron-sulfur cluster carrier proteins [8]. Lipoylation is essential for the function of several key enzymes involved in oxidative metabolism, as it converts apoprotein into the biologically active holoprotein. Examples of such lipoylated proteins include pyruvate dehydrogenase (E2 domain), 2-oxoglutarate dehydrogenase (E2 domain), the branched-chain 2-oxoacid dehydrogenases and the glycine cleavage system (H protein) [1,2]. An alternative lipoylation pathway involves EC 6.3.1.20, lipoate—protein ligase, which can lipoylate apoproteins using exogenous lipoic acid (or its analogues) [4].
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 189398-80-9
References:
1.  Cicchillo, R.M. and Booker, S.J. Mechanistic investigations of lipoic acid biosynthesis in Escherichia coli: both sulfur atoms in lipoic acid are contributed by the same lipoyl synthase polypeptide. J. Am. Chem. Soc. 127 (2005) 2860–2861. [DOI] [PMID: 15740115]
2.  Vanden Boom, T.J., Reed, K.E. and Cronan, J.E., Jr. Lipoic acid metabolism in Escherichia coli: isolation of null mutants defective in lipoic acid biosynthesis, molecular cloning and characterization of the E. coli lip locus, and identification of the lipoylated protein of the glycine cleavage system. J. Bacteriol. 173 (1991) 6411–6420. [DOI] [PMID: 1655709]
3.  Zhao, X., Miller, J.R., Jiang, Y., Marletta, M.A. and Cronan, J.E. Assembly of the covalent linkage between lipoic acid and its cognate enzymes. Chem. Biol. 10 (2003) 1293–1302. [DOI] [PMID: 14700636]
4.  Cicchillo, R.M., Iwig, D.F., Jones, A.D., Nesbitt, N.M., Baleanu-Gogonea, C., Souder, M.G., Tu, L. and Booker, S.J. Lipoyl synthase requires two equivalents of S-adenosyl-L-methionine to synthesize one equivalent of lipoic acid. Biochemistry 43 (2004) 6378–6386. [DOI] [PMID: 15157071]
5.  Jordan, S.W. and Cronan, J.E., Jr. A new metabolic link. The acyl carrier protein of lipid synthesis donates lipoic acid to the pyruvate dehydrogenase complex in Escherichia coli and mitochondria. J. Biol. Chem. 272 (1997) 17903–17906. [DOI] [PMID: 9218413]
6.  Miller, J.R., Busby, R.W., Jordan, S.W., Cheek, J., Henshaw, T.F., Ashley, G.W., Broderick, J.B., Cronan, J.E., Jr. and Marletta, M.A. Escherichia coli LipA is a lipoyl synthase: in vitro biosynthesis of lipoylated pyruvate dehydrogenase complex from octanoyl-acyl carrier protein. Biochemistry 39 (2000) 15166–15178. [DOI] [PMID: 11106496]
7.  Perham, R.N. Swinging arms and swinging domains in multifunctional enzymes: catalytic machines for multistep reactions. Annu. Rev. Biochem. 69 (2000) 961–1004. [DOI] [PMID: 10966480]
8.  McCarthy, E.L. and Booker, S.J. Destruction and reformation of an iron-sulfur cluster during catalysis by lipoyl synthase. Science 358 (2017) 373–377. [DOI] [PMID: 29051382]
[EC 2.8.1.8 created 2006, modified 2014, modified 2018]
 
 
EC 2.8 Transferring sulfur-containing groups
 
EC 2.8.5 Thiosulfotransferases
 
EC 2.8.5.1
Accepted name: S-sulfo-L-cysteine synthase (3-phospho-L-serine-dependent)
Reaction: 3-phospho-L-serine + thiosulfate = S-sulfo-L-cysteine + phosphate
Other name(s): cysK2 (gene name)
Systematic name: thiosulfate:3-phospho-L-serine thiosulfotransferase
Comments: The enzyme, which has been characterized from the bacterium Mycobacterium tuberculosis, has no activity with O-acetyl-L-serine. Requires pyridoxal 5′-phosphate. cf. EC 2.5.1.144, S-sulfo-L-cysteine synthase (O-acetyl-L-serine-dependent).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Steiner, E.M., Both, D., Lossl, P., Vilaplana, F., Schnell, R. and Schneider, G. CysK2 from Mycobacterium tuberculosis is an O-phospho-L-serine-dependent S-sulfocysteine synthase. J. Bacteriol. 196 (2014) 3410–3420. [DOI] [PMID: 25022854]
[EC 2.8.5.1 created 2018]
 
 
EC 3.1.6.20
Accepted name: S-sulfosulfanyl-L-cysteine sulfohydrolase
Reaction: (1) [SoxY protein]-S-sulfosulfanyl-L-cysteine + H2O = [SoxY protein]-S-sulfanyl-L-cysteine + sulfate
(2) [SoxY protein]-S-(2-sulfodisulfanyl)-L-cysteine + H2O = [SoxY protein]-S-disulfanyl-L-cysteine + sulfate
Other name(s): SoxB
Systematic name: [SoxY protein]-S-sulfosulfanyl-L-cysteine sulfohydrolase
Comments: Contains Mn2+. The enzyme is part of the Sox enzyme system, which participates in a bacterial thiosulfate oxidation pathway that produces sulfate. It catalyses two reactions in the pathway. In both cases the enzyme hydrolyses a sulfonate moiety that is bound (either directly or via a sulfane) to a cysteine residue of a SoxY protein, releasing sulfate. The enzyme from Paracoccus pantotrophus contains a pyroglutamate (cycloglutamate) at its N-terminus.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Quentmeier, A. and Friedrich, C.G. The cysteine residue of the SoxY protein as the active site of protein-bound sulfur oxidation of Paracoccus pantotrophus GB17. FEBS Lett. 503 (2001) 168–172. [PMID: 11513876]
2.  Friedrich, C.G., Rother, D., Bardischewsky, F., Quentmeier, A. and Fischer, J. Oxidation of reduced inorganic sulfur compounds by bacteria: emergence of a common mechanism. Appl. Environ. Microbiol. 67 (2001) 2873–2882. [DOI] [PMID: 11425697]
3.  Quentmeier, A., Hellwig, P., Bardischewsky, F., Grelle, G., Kraft, R. and Friedrich, C.G. Sulfur oxidation in Paracoccus pantotrophus: interaction of the sulfur-binding protein SoxYZ with the dimanganese SoxB protein. Biochem. Biophys. Res. Commun. 312 (2003) 1011–1018. [PMID: 14651972]
4.  Epel, B., Schafer, K.O., Quentmeier, A., Friedrich, C. and Lubitz, W. Multifrequency EPR analysis of the dimanganese cluster of the putative sulfate thiohydrolase SoxB of Paracoccus pantotrophus. J. Biol. Inorg. Chem. 10 (2005) 636–642. [PMID: 16133204]
5.  Hensen, D., Sperling, D., Truper, H.G., Brune, D.C. and Dahl, C. Thiosulphate oxidation in the phototrophic sulphur bacterium Allochromatium vinosum. Mol. Microbiol. 62 (2006) 794–810. [PMID: 16995898]
6.  Grabarczyk, D.B. and Berks, B.C. Intermediates in the Sox sulfur oxidation pathway are bound to a sulfane conjugate of the carrier protein SoxYZ. PLoS One 12:e0173395 (2017). [DOI] [PMID: 28257465]
[EC 3.1.6.20 created 2018]
 
 
*EC 3.2.1.106
Accepted name: mannosyl-oligosaccharide glucosidase
Reaction: Glc3Man9GlcNAc2-[protein] + H2O = Glc2Man9GlcNAc2-[protein] + β-D-glucopyranose
Glossary: Glc3Man9GlcNAc2 = [α-D-Glc-(1→2)-α-D-Glc-(1→3)-α-D-Glc-(1→3)-α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-{α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)}-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc]-N-Asn-[protein]
Glc2Man9GlcNAc2-[protein] = [α-D-Glc-(1→3)-α-D-Glc-(1→3)-α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-{α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)}-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc]-N-Asn-[protein]
Other name(s): Glc3Man9NAc2 oligosaccharide glucosidase; trimming glucosidase I; CWH41 (gene name); MOGS (gene name); mannosyl-oligosaccharide glucohydrolase
Systematic name: Glc3Man9GlcNAc2-[protein] glucohydrolase (configuration-inverting)
Comments: This enzyme catalyses the first step in the processing of the N-glycan tetradecasaccharide precursor Glc3Man9GlcNAc2, which takes place in the endoplasmic reticulum, by removing the distal α-1,2-linked glucose residue. This and subsequent processing steps are required before complex N-glycans can be synthesized.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 78413-07-7
References:
1.  Elting, J.J., Chen, W.W. and Lennarz, J. Characterization of a glucosidase involved in an initial step in the processing of oligosaccharide chains. J. Biol. Chem. 255 (1980) 2325–2331. [PMID: 7358674]
2.  Grinna, L.S. and Robbins, P.W. Glycoprotein biosynthesis. Rat liver microsomal glucosidases which process oligosaccharides. J. Biol. Chem. 254 (1979) 8814–8818. [PMID: 479161]
3.  Kilker, R.D., Saunier, B., Tkacz, J.S. and Herscovics, A. Partial purification from Saccharomyces cerevisiae of a soluble glucosidase which removes the terminal glucose from the oligosaccharide Glc3Man9GlcNAc2. J. Biol. Chem. 256 (1981) 5299–5603. [PMID: 7014569]
4.  Grinna, L.S. and Robbins, P.W. Substrate specificities of rat liver microsomal glucosidases which process glycoproteins. J. Biol. Chem. 255 (1980) 2255–2258. [PMID: 7358666]
5.  Mark, M.J. and Kornfeld, S. Partial purification and characterization of the glucosidases involved in the processing of asparagine-linked oligosaccharides. Arch. Biochem. Biophys. 199 (1980) 249–258. [DOI] [PMID: 7356331]
[EC 3.2.1.106 created 1984, modified 2018]
 
 
*EC 3.2.1.114
Accepted name: mannosyl-oligosaccharide 1,3-1,6-α-mannosidase
Reaction: Man5GlcNAc3-[protein] + 2 H2O = Man3GlcNAc3-[protein] + 2 α-D-mannopyranose
For diagram of mannosyl-glycoprotein n-acetylglucosaminyltransferases, click here
Glossary: Man5GlcNAc3-[protein] = [β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-{α-D-Man-(1→3)-[α-D-Man-(1→6)]-α-D-Man-(1→6)}-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc]-N-Asn-[protein]
Man3GlcNAc3-[protein] = {β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-N-Asn-[protein]
Other name(s): MAN2A1 (gene name); MAN2A2 (gene name); mannosidase II; exo-1,3-1,6-α-mannosidase; α-D-mannosidase II; α-mannosidase II; α1-3,6-mannosidase; GlcNAc transferase I-dependent α1,3[α1,6]mannosidase; Golgi α-mannosidase II; ManII; 1,3(1,6)-α-D-mannosidase; 1,3-(1,6-)mannosyl-oligosaccharide α-D-mannohydrolase; (1→3)-(1→6)-mannosyl-oligosaccharide α-D-mannohydrolase
Systematic name: (1→3)-(1→6)-mannosyl-oligosaccharide α-D-mannohydrolase (configuration-retaining)
Comments: The enzyme, found in plants and animals, participates in the processing of N-glycans in the Golgi apparatus. It removes two mannosyl residues, one linked by α1,3 linkage, and the other linked by α1,6 linkage, both of which are removed by the same catalytic site. The enzyme is sensitive to swainsonine.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, PDB, CAS registry number: 82047-77-6
References:
1.  Tulsiani, D.R.P., Opheim, D.J. and Touster, O. Purification and characterization of α-D-mannosidase from rat liver golgi membranes. J. Biol. Chem. 252 (1977) 3227–3233. [PMID: 863880]
2.  Tabas, I. and Kornfeld, S. The synthesis of complex-type oligosaccharides. III. Identification of an α-D-mannosidase activity involved in a late stage of processing of complex-type oligosaccharides. J. Biol. Chem. 253 (1978) 7779–7786. [PMID: 212436]
3.  Harpaz, N. and Schachter, H. Control of glycoprotein synthesis. Processing of asparagine-linked oligosaccharides by one or more rat liver Golgi α-D-mannosidases dependent on the prior action of UDP-N-acetylglucosamine: α-D-mannoside β2-N-acetylglucosaminyltransferase I. J. Biol. Chem. 255 (1980) 4894–4902. [PMID: 6445359]
4.  Tulsiani, D.R.P., Hubbard, S.C., Robbins, P.W. and Touster, O. α-D-Mannosidases of rat liver Golgi membranes. Mannosidase II is the GlcNAcMAN5-cleaving enzyme in glycoprotein biosynthesis and mannosidases IA and IB are the enzymes converting Man9 precursors to Man5 intermediates. J. Biol. Chem. 257 (1982) 3660–3668. [PMID: 7061502]
5.  Moremen, K.W. and Robbins, P.W. Isolation, characterization, and expression of cDNAs encoding murine α-mannosidase II, a Golgi enzyme that controls conversion of high mannose to complex N-glycans. J. Cell Biol. 115 (1991) 1521–1534. [PMID: 1757461]
6.  Misago, M., Liao, Y.F., Kudo, S., Eto, S., Mattei, M.G., Moremen, K.W. and Fukuda, M.N. Molecular cloning and expression of cDNAs encoding human α-mannosidase II and a previously unrecognized α-mannosidase IIx isozyme. Proc. Natl Acad. Sci. USA 92 (1995) 11766–11770. [DOI] [PMID: 8524845]
7.  van den Elsen, J.M., Kuntz, D.A. and Rose, D.R. Structure of Golgi α-mannosidase II: a target for inhibition of growth and metastasis of cancer cells. EMBO J. 20 (2001) 3008–3017. [DOI] [PMID: 11406577]
8.  Athanasopoulos, V.I., Niranjan, K. and Rastall, R.A. The production, purification and characterisation of two novel α-D-mannosidases from Aspergillus phoenicis. Carbohydr. Res. 340 (2005) 609–617. [DOI] [PMID: 15721331]
9.  Shah, N., Kuntz, D.A. and Rose, D.R. Golgi α-mannosidase II cleaves two sugars sequentially in the same catalytic site. Proc. Natl Acad. Sci. USA 105 (2008) 9570–9575. [DOI] [PMID: 18599462]
10.  Rose, D.R. Structure, mechanism and inhibition of Golgi α-mannosidase II. Curr. Opin. Struct. Biol. 22 (2012) 558–562. [DOI] [PMID: 22819743]
[EC 3.2.1.114 created 1986, modified 2018]
 
 
*EC 3.2.1.170
Accepted name: mannosylglycerate hydrolase
Reaction: 2-O-(α-D-mannopyranosyl)-D-glycerate + H2O = D-mannopyranose + D-glycerate
Other name(s): MgH
Systematic name: 2-O-(α-D-mannopyranosyl)-D-glycerate D-mannohydrolase
Comments: The enzyme occurs in thermophilic bacteria and has been characterized in Thermus thermophilus and Rubrobacter radiotolerans. It also has been identified in the moss Selaginella moellendorffii.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Alarico, S., Empadinhas, N. and da Costa, M.S. A new bacterial hydrolase specific for the compatible solutes α-D-mannopyranosyl-(1→2)-D-glycerate and α-D-glucopyranosyl-(1→2)-D-glycerate. Enzyme Microb. Technol. 52 (2013) 77–83. [DOI] [PMID: 23273275]
2.  Nobre, A., Empadinhas, N., Nobre, M.F., Lourenco, E.C., Maycock, C., Ventura, M.R., Mingote, A. and da Costa, M.S. The plant Selaginella moellendorffii possesses enzymes for synthesis and hydrolysis of the compatible solutes mannosylglycerate and glucosylglycerate. Planta 237 (2013) 891–901. [DOI] [PMID: 23179444]
[EC 3.2.1.170 created 2011, modified 2018]
 
 
EC 3.2.1.207
Accepted name: mannosyl-oligosaccharide α-1,3-glucosidase
Reaction: (1) Glc2Man9GlcNAc2-[protein] + H2O = GlcMan9GlcNAc2-[protein] + β-D-glucopyranose
(2) GlcMan9GlcNAc2-[protein] + H2O = Man9GlcNAc2-[protein] + β-D-glucopyranose
Glossary: Glc2Man9GlcNAc2-[protein] = {α-D-Glc-(1→3)-α-D-Glc-(1→3)-α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-N-Asn-[protein]
GlcMan9GlcNAc2-[protein] = {α-D-Glc-(1→3)-α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-N-Asn-[protein]
Man9GlcNAc2-[protein] = {α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-N-Asn-[protein]
Other name(s): ER glucosidase II; α-glucosidase II; trimming glucosidase II; ROT2 (gene name); GTB1 (gene name); GANAB (gene name); PRKCSH (gene name)
Systematic name: Glc2Man9GlcNAc2-[protein] 3-α-glucohydrolase (configuration-inverting)
Comments: This eukaryotic enzyme cleaves off sequentially the two α-1,3-linked glucose residues from the Glc2Man9GlcNAc2 oligosaccharide precursor of immature N-glycosylated proteins.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Trombetta, E.S., Simons, J.F. and Helenius, A. Endoplasmic reticulum glucosidase II is composed of a catalytic subunit, conserved from yeast to mammals, and a tightly bound noncatalytic HDEL-containing subunit. J. Biol. Chem. 271 (1996) 27509–27516. [DOI] [PMID: 8910335]
2.  Ziak, M., Meier, M., Etter, K.S. and Roth, J. Two isoforms of trimming glucosidase II exist in mammalian tissues and cell lines but not in yeast and insect cells. Biochem. Biophys. Res. Commun. 280 (2001) 363–367. [DOI] [PMID: 11162524]
3.  Wilkinson, B.M., Purswani, J. and Stirling, C.J. Yeast GTB1 encodes a subunit of glucosidase II required for glycoprotein processing in the endoplasmic reticulum. J. Biol. Chem. 281 (2006) 6325–6333. [DOI] [PMID: 16373354]
4.  Mora-Montes, H.M., Bates, S., Netea, M.G., Diaz-Jimenez, D.F., Lopez-Romero, E., Zinker, S., Ponce-Noyola, P., Kullberg, B.J., Brown, A.J., Odds, F.C., Flores-Carreon, A. and Gow, N.A. Endoplasmic reticulum α-glycosidases of Candida albicans are required for N glycosylation, cell wall integrity, and normal host-fungus interaction. Eukaryot Cell 6 (2007) 2184–2193. [DOI] [PMID: 17933909]
[EC 3.2.1.207 created 2018]
 
 
*EC 3.3.1.2
Accepted name: S-adenosyl-L-methionine hydrolase (L-homoserine-forming)
Reaction: S-adenosyl-L-methionine + H2O = L-homoserine + S-methyl-5′-thioadenosine
Glossary: S-methyl-L-methionine sulfonium salt = (S)-3-amino-3-carboxypropyldi(methyl)sulfonium salt
Other name(s): S-adenosylmethionine cleaving enzyme; methylmethionine-sulfonium-salt hydrolase; adenosylmethionine lyase; adenosylmethionine hydrolase; S-adenosylmethionine hydrolase; S-adenosyl-L-methionine hydrolase
Systematic name: S-adenosyl-L-methionine hydrolase (L-homoserine-forming)
Comments: Also hydrolyses S-methyl-L-methionine to dimethyl sulfide and homoserine. cf. EC 3.13.1.8, S-adenosyl-L-methionine hydrolase (adenosine-forming).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 37288-62-3
References:
1.  Mazelis, M., Levin, B. and Mallinson, N. Decomposition of methyl methionine sulfonium salts by a bacterial enzyme. Biochim. Biophys. Acta 105 (1965) 106–114. [PMID: 5849106]
[EC 3.3.1.2 created 1972, modified 1976, modified 2018]
 
 
EC 3.5.1.128
Accepted name: deaminated glutathione amidase
Reaction: N-(4-oxoglutaryl)-L-cysteinylglycine + H2O = 2-oxoglutarate + L-cysteinylglycine
Glossary: N-(4-oxoglutaryl)-L-cysteinylglycine = deaminated glutathione
Other name(s): dGSH deaminase; NIT1 (gene name)
Systematic name: N-(4-oxoglutaryl)-L-cysteinylglycine amidohydrolase
Comments: The enzyme, present in animals, fungi and bacteria, is involved in clearing cells of the toxic compound deaminated glutathione, which can be produced as an unwanted side product by several transaminases.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Peracchi, A., Veiga-da-Cunha, M., Kuhara, T., Ellens, K.W., Paczia, N., Stroobant, V., Seliga, A.K., Marlaire, S., Jaisson, S., Bommer, G.T., Sun, J., Huebner, K., Linster, C.L., Cooper, A.JL. and Van Schaftingen, E. Nit1 is a metabolite repair enzyme that hydrolyzes deaminated glutathione. Proc. Natl Acad. Sci. USA 114 (2017) E3233–E3242. [DOI] [PMID: 28373563]
[EC 3.5.1.128 created 2018]
 
 
*EC 3.7.1.4
Accepted name: phloretin hydrolase
Reaction: phloretin + H2O = phloretate + phloroglucinol
For diagram of phloretin biosynthesis, click here
Glossary: phloretin = 3-(4-hydroxyphenyl)-1-(2,4,6-trihydroxyphenyl)propan-1-one
phloretate = 3-(4-hydroxyphenyl)propanoate
phloroglucinol = benzene-1,3,5-triol
Other name(s): ErPhy; lactase-phlorerin hydrolase; C-acylphenol hydrolase; 2′,4,4′,6′-tetrahydroxydehydrochalcone 1,3,5-trihydroxybenzenehydrolase (incorrect)
Systematic name: phloretin acylhydrolase (phloroglucinol forming)
Comments: Also hydrolyses other C-acylated phenols related to phloretin. Isolated from the fungus Aspergillus niger and the bacteria Pantoea agglomerans and Eubacterium ramulus.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG, CAS registry number: 37289-38-6
References:
1.  Chatterjee, A.K. and Gibbins, L.N. Metabolism of phloridzin by Erwinia herbicola: nature of the degradation products, and the purification and properties of phloretin hydrolase. J. Bacteriol. 100 (1969) 594–600. [PMID: 5354935]
2.  Minamikawa, T., Jayasankar, N.P., Bohm, B.A., Taylor, I.E. and Towers, G.H. An inducible hydrolase from Aspergillus niger, acting on carbon-carbon bonds, for phlorrhizin and other C-acylated phenols. Biochem. J. 116 (1970) 889–897. [PMID: 5441377]
3.  Schoefer, L., Braune, A. and Blaut, M. Cloning and expression of a phloretin hydrolase gene from Eubacterium ramulus and characterization of the recombinant enzyme. Appl. Environ. Microbiol. 70 (2004) 6131–6137. [DOI] [PMID: 15466559]
[EC 3.7.1.4 created 1972, modified 2018]
 
 
EC 3.13.1.8
Accepted name: S-adenosyl-L-methionine hydrolase (adenosine-forming)
Reaction: S-adenosyl-L-methionine + H2O = adenosine + L-methionine
Other name(s): SAM hydroxide adenosyltransferase
Systematic name: S-adenosyl-L-methionine hydrolase (adenosine-forming)
Comments: The enzyme, found in bacteria and archaea, catalyses a nucleophilic attack of water at the C5′ carbon of S-adenosyl-L-methionine to generate adenosine and L-methionine. May be involved in regulating SAM levels in the cell. cf. EC 3.3.1.2, S-adenosyl-L-methionine hydrolase (L-homoserine-forming).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Eustaquio, A.S., Harle, J., Noel, J.P. and Moore, B.S. S-Adenosyl-L-methionine hydrolase (adenosine-forming), a conserved bacterial and archaeal protein related to SAM-dependent halogenases. Chembiochem 9 (2008) 2215–2219. [DOI] [PMID: 18720493]
2.  Deng, H., McMahon, S.A., Eustaquio, A.S., Moore, B.S., Naismith, J.H. and O'Hagan, D. Mechanistic insights into water activation in SAM hydroxide adenosyltransferase (duf-62). Chembiochem 10 (2009) 2455–2459. [DOI] [PMID: 19739191]
[EC 3.13.1.8 created 2018]
 
 
EC 4.1.1.110
Accepted name: bisphosphomevalonate decarboxylase
Reaction: (R)-3,5-bisphosphomevalonate = isopentenyl phosphate + CO2 + phosphate
Other name(s): mevalonate 3,5-bisphosphate decarboxylase
Systematic name: (R)-3,5-bisphosphomevalonate carboxy-lyase (isopentenyl-phosphate-forming)
Comments: The enzyme participates in an alternative mevalonate pathway that takes place in extreme acidophiles of the Thermoplasmatales order. cf. EC 4.1.1.99, phosphomevalonate decarboxylase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Vinokur, J.M., Cummins, M.C., Korman, T.P. and Bowie, J.U. An adaptation to life in acid through a novel mevalonate pathway. Sci Rep 6 (2016) 39737. [DOI] [PMID: 28004831]
[EC 4.1.1.110 created 2018]
 
 
EC 4.1.1.111
Accepted name: siroheme decarboxylase
Reaction: siroheme = 12,18-didecarboxysiroheme + 2 CO2
For diagram of siroheme decarboxylase, click here
Other name(s): sirohaem decarboxylase; nirDLHG (gene name); ahbABC (gene name)
Systematic name: siroheme carboxy-lyase
Comments: The enzyme from archaea is involved in an alternative heme biosynthesis pathway. The enzyme from denitrifying bacteria is involved in the heme d1 biosynthesis pathway.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Bali, S., Lawrence, A.D., Lobo, S.A., Saraiva, L.M., Golding, B.T., Palmer, D.J., Howard, M.J., Ferguson, S.J. and Warren, M.J. Molecular hijacking of siroheme for the synthesis of heme and d1 heme. Proc. Natl Acad. Sci. USA 108 (2011) 18260–18265. [DOI] [PMID: 21969545]
2.  Kuhner, M., Haufschildt, K., Neumann, A., Storbeck, S., Streif, J. and Layer, G. The alternative route to heme in the methanogenic archaeon Methanosarcina barkeri. Archaea 2014:327637 (2014). [DOI] [PMID: 24669201]
3.  Palmer, D.J., Schroeder, S., Lawrence, A.D., Deery, E., Lobo, S.A., Saraiva, L.M., McLean, K.J., Munro, A.W., Ferguson, S.J., Pickersgill, R.W., Brown, D.G. and Warren, M.J. The structure, function and properties of sirohaem decarboxylase--an enzyme with structural homology to a transcription factor family that is part of the alternative haem biosynthesis pathway. Mol. Microbiol. 93 (2014) 247–261. [DOI] [PMID: 24865947]
4.  Haufschildt, K., Schmelz, S., Kriegler, T.M., Neumann, A., Streif, J., Arai, H., Heinz, D.W. and Layer, G. The crystal structure of siroheme decarboxylase in complex with iron-uroporphyrin III reveals two essential histidine residues. J. Mol. Biol. 426 (2014) 3272–3286. [DOI] [PMID: 25083922]
[EC 4.1.1.111 created 2018]
 
 
EC 4.4.1.37
Accepted name: pyridinium-3,5-bisthiocarboxylic acid mononucleotide synthase
Reaction: (1) [LarE]-L-cysteine + pyridin-1-ium-3,5-dicarboxylate mononucleotide + ATP = [LarE]-dehydroalanine + pyridin-1-ium-3-carboxylate-5-thiocarboxylate mononucleotide + AMP + diphosphate (overall reaction)
(1a) ATP + pyridin-1-ium-3,5-dicarboxylate mononucleotide = diphosphate + 5-carboxy-1-(5-O-phospho-β-D-ribofuranosyl)pyridin-1-ium-3-carbonyl adenylate
(1b) 5-carboxy-1-(5-O-phospho-β-D-ribofuranosyl)pyridin-1-ium-3-carbonyl adenylate + [LarE]-L-cysteine = AMP + [LarE]-S-[5-carboxy-1-(5-O-phosphono-β-D-ribofuranosyl)pyridin-1-ium-3-carbonyl]-L-cysteine
(1c) [LarE]-S-[5-carboxy-1-(5-O-phosphono-β-D-ribofuranosyl)pyridin-1-ium-3-carbonyl]-L-cysteine = [LarE]-dehydroalanine + pyridin-1-ium-3-carboxylate-5-thiocarboxylate mononucleotide
(2) [LarE]-L-cysteine + pyridin-1-ium-3-carboxylate-5-thiocarboxylate mononucleotide + ATP = [LarE]-dehydroalanine + pyridin-1-ium-3,5-bisthiocarboxylate mononucleotide + AMP + diphosphate (overall reaction)
(2a) ATP + pyridin-1-ium-3-carboxylate-5-thiocarboxylate mononucleotide = diphosphate + 1-(5-O-phospho-β-D-ribofuranosyl)-5-(sulfanylcarbonyl)pyridin-1-ium-3-carbonyl adenylate
(2b) 1-(5-O-phospho-β-D-ribofuranosyl)-5-(sulfanylcarbonyl)pyridin-1-ium-3-carbonyl adenylate + [LarE]-L-cysteine = AMP + [LarE]-S-[1-(5-O-phosphono-β-D-ribofuranosyl)-5-(sulfanylcarbonyl)pyridin-1-ium-3-carbonyl]-L-cysteine
(2c) [LarE]-S-[1-(5-O-phosphono-β-D-ribofuranosyl)-5-(sulfanylcarbonyl)pyridin-1-ium-3-carbonyl]-L-cysteine = [LarE]-dehydroalanine + pyridin-1-ium-3,5-bisthiocarboxylate mononucleotide
Other name(s): LarE; P2CMN sulfurtransferase; pyridinium-3,5-biscarboxylic acid mononucleotide sulfurtransferase; P2TMN synthase
Systematic name: [LarE]-S-[1-(5-O-phosphono-β-D-ribofuranosyl)-5-(sulfanylcarbonyl)pyridin-1-ium-3-carbonyl]-L-cysteine pyridin-1-ium-3,5-dicarbothioate-mononucleotide-lyase (ATP-consuming)
Comments: This enzyme, found in Lactobacillus plantarum, is involved in the biosynthesis of a nickel-pincer cofactor. The process starts when one enzyme molecule adenylates pyridinium-3,5-dicarboxylate mononucleotide (P2CMN) and covalently binds the adenylated product to an intrinsic cysteine residue. Next, the enzyme cleaves the carbon-sulfur bond, liberating pyridinium-3-carboxylate-5-thiocarboxylate mononucleotide (PCTMN) and leaving a 2-aminoprop-2-enoate (dehydroalanine) residue attached to the protein. Since the cysteine residue is not regenerated in vivo, the enzyme is inactivated during the process. A second enzyme molecule then repeats the process with PCTMN, adenylating it and covalently binding it to the same cysteine residue, followed by liberation of pyridinium-3,5-bisthiocarboxylate mononucleotide (P2TMN) and the inactivation of the second enzyme molecule.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Desguin, B., Goffin, P., Viaene, E., Kleerebezem, M., Martin-Diaconescu, V., Maroney, M.J., Declercq, J.P., Soumillion, P. and Hols, P. Lactate racemase is a nickel-dependent enzyme activated by a widespread maturation system. Nat Commun 5:3615 (2014). [DOI] [PMID: 24710389]
2.  Desguin, B., Soumillion, P., Hols, P. and Hausinger, R.P. Nickel-pincer cofactor biosynthesis involves LarB-catalyzed pyridinium carboxylation and LarE-dependent sacrificial sulfur insertion. Proc. Natl Acad. Sci. USA 113 (2016) 5598–5603. [DOI] [PMID: 27114550]
3.  Fellner, M., Desguin, B., Hausinger, R.P. and Hu, J. Structural insights into the catalytic mechanism of a sacrificial sulfur insertase of the N-type ATP pyrophosphatase family, LarE. Proc. Natl Acad. Sci. USA 114 (2017) 9074–9079. [DOI] [PMID: 28784764]
[EC 4.4.1.37 created 2018]
 
 
EC 5.3.3.22
Accepted name: lutein isomerase
Reaction: lutein = meso-zeaxanthin
For diagram of lutein biosynthesis, click here
Glossary: lutein = (3R,3′R)-dihydroxy-α-carotene
meso-zeaxanthin = (3R,3′S)-β,β-carotene-3,3′-diol
Other name(s): RPE65 (gene name); meso-zeaxanthin isomerase
Systematic name: lutein Δ45-isomerase
Comments: The enzyme is found in the retinal pigment epithelium (RPE) of vertebrates. It also has the activity of EC 3.1.1.64, retinoid isomerohydrolase.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Shyam, R., Gorusupudi, A., Nelson, K., Horvath, M.P. and Bernstein, P.S. RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. Proc. Natl Acad. Sci. USA 114 (2017) 10882–10887. [DOI] [PMID: 28874556]
[EC 5.3.3.22 created 2018]
 
 
EC 5.5.1.31
Accepted name: hapalindole H synthase
Reaction: 3-geranyl-3-[(Z)-2-isocyanoethenyl]-1H-indole = hapalindole H
For diagram of Hapalindole/Fischerindole biosynthesis, click here
Glossary: hapalindole H = (6aR,9R,10R,10aR)-9-ethenyl-1-isocyano-6,6,9-trimethyl-2,6,6a,7,8,9,10,10a-decahydronaphtho[1,2,3-cd]indole
Other name(s): famC2 (gene name); famC3 (gene name)
Systematic name: 3-geranyl-3-[(Z)-2-isocyanoethenyl]-1H-indole cyclase (hapalindole H-forming)
Comments: The enzyme, characterized from the cyanobacterium Fischerella ambigua UTEX 1903, forms the core structure of the hapalindole family of alkaloids. The enzyme is a heterodimeric complex.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Li, S., Lowell, A.N., Newmister, S.A., Yu, F., Williams, R.M. and Sherman, D.H. Decoding cyclase-dependent assembly of hapalindole and fischerindole alkaloids. Nat. Chem. Biol. 13 (2017) 467–469. [DOI] [PMID: 28288107]
[EC 5.5.1.31 created 2018]
 
 
EC 5.5.1.32
Accepted name: 12-epi-hapalindole U synthase
Reaction: 3-geranyl-3-[(Z)-2-isocyanoethenyl]-1H-indole = 12-epi-hapalindole U
For diagram of Hapalindole/Fischerindole biosynthesis, click here
Glossary: 12-epi-hapalindole H = (6aR,9S,10R,10aR)-9-ethenyl-1-isocyano-6,6,9-trimethyl-2,6,6a,7,8,9,10,10a-decahydronaphtho[1,2,3-cd]indole
Other name(s): famC1 (gene name); HpiC1 (gene name)
Systematic name: 3-geranyl-3-[(Z)-2-isocyanoethenyl]-1H-indole cyclase (12-epi-hapalindole U-forming)
Comments: The enzyme, characterized from the cyanobacterium Fischerella ambigua UTEX 1903, forms the core structure of the 12-epi-hapalindole family of alkaloids.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Li, S., Lowell, A.N., Yu, F., Raveh, A., Newmister, S.A., Bair, N., Schaub, J.M., Williams, R.M. and Sherman, D.H. Hapalindole/ambiguine biogenesis Is mediated by a Cope rearrangement, C-C bond-forming cascade. J. Am. Chem. Soc. 137 (2015) 15366–15369. [DOI] [PMID: 26629885]
[EC 5.5.1.32 created 2018]
 
 
EC 5.5.1.33
Accepted name: 12-epi-fischerindole U synthase
Reaction: 3-geranyl-3-[(Z)-2-isocyanoethenyl]-1H-indole = 12-epi-fischerindole U
For diagram of Hapalindole/Fischerindole biosynthesis, click here
Glossary: 12-epi-fischerindole U = (6aS,9S,10R,10aS)-9-ethenyl-10-isocyano-6,6,9-trimethyl-5H,6aH,7H,8H,10H,10aH-indeno[2,1-b]indole
Other name(s): fisC (gene name); fimC5 (gene name)
Systematic name: 3-geranyl-3-[(Z)-2-isocyanoethenyl]-1H-indole cyclase (12-epi-fischerindole U-forming)
Comments: The enzyme, characterized from multiple species of the cyanobacterial genus Fischerella, participates in the biosynthesis of the terpenoid indole alkaloids 12-epi-fischerindoles.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Li, S., Lowell, A.N., Newmister, S.A., Yu, F., Williams, R.M. and Sherman, D.H. Decoding cyclase-dependent assembly of hapalindole and fischerindole alkaloids. Nat. Chem. Biol. 13 (2017) 467–469. [DOI] [PMID: 28288107]
[EC 5.5.1.33 created 2018]
 
 
EC 6.2.1.53
Accepted name: L-proline—[L-prolyl-carrier protein] ligase
Reaction: ATP + L-proline + holo-[L-prolyl-carrier protein] = AMP + diphosphoate + L-prolyl-[L-prolyl-carrier protein] (overall reaction)
(1a) ATP + L-proline = diphosphate + (L-prolyl)adenylate
(1b) (L-prolyl)adenylate + holo-[L-prolyl-carrier protein] = AMP + L-prolyl-[L-prolyl-carrier protein]
Other name(s): pltF (gene name); bmp4 (gene name); pigI (gene name)
Systematic name: L-proline:[L-prolyl-carrier protein] ligase (AMP-forming)
Comments: The enzyme participates in the biosynthesis of several pyrrole-containing compounds, such as undecylprodigiosin, prodigiosin, pyoluteorin, and coumermycin A1. It catalyses the activation of L-proline to an adenylate form, followed by its transfer to the 4′-phosphopantheine moiety of an L-prolyl-carrier protein.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Thomas, M.G., Burkart, M.D. and Walsh, C.T. Conversion of L-proline to pyrrolyl-2-carboxyl-S-PCP during undecylprodigiosin and pyoluteorin biosynthesis. Chem. Biol. 9 (2002) 171–184. [DOI] [PMID: 11880032]
2.  Harris, A.K., Williamson, N.R., Slater, H., Cox, A., Abbasi, S., Foulds, I., Simonsen, H.T., Leeper, F.J. and Salmond, G.P. The Serratia gene cluster encoding biosynthesis of the red antibiotic, prodigiosin, shows species- and strain-dependent genome context variation. Microbiology 150 (2004) 3547–3560. [DOI] [PMID: 15528645]
3.  Williamson, N.R., Simonsen, H.T., Ahmed, R.A., Goldet, G., Slater, H., Woodley, L., Leeper, F.J. and Salmond, G.P. Biosynthesis of the red antibiotic, prodigiosin, in Serratia: identification of a novel 2-methyl-3-n-amyl-pyrrole (MAP) assembly pathway, definition of the terminal condensing enzyme, and implications for undecylprodigiosin biosynthesis in Streptomyces. Mol. Microbiol. 56 (2005) 971–989. [DOI] [PMID: 15853884]
[EC 6.2.1.53 created 2018]
 
 
EC 6.2.1.54
Accepted name: D-alanine—[D-alanyl-carrier protein] ligase
Reaction: ATP + D-alanine + holo-[D-alaninyl-carrier protein] = AMP + diphosphate + D-alanyl-[D-alanyl-carrier protein] (overall reaction)
(1a) ATP + D-alanine = (D-alanyl)adenylate + diphosphate
(1b) (D-alanyl)adenylate + holo-[D-alanyl-carrier protein] = AMP + D-alanyl-[D-alanyl-carrier protein]
Other name(s): dltA (gene name); Dcl
Systematic name: D-alanine:[D-alanyl-carrier protein] ligase
Comments: The enzyme is involved in the modification of wall teichoic acids, as well as type I and IV lipoteichoic acids, with D-alanine residues. It activates D-alanine using ATP to form a high-energy (D-alanyl)adenylate intermediate and subsequently transfers the alanyl moiety to the phosphopantheinyl prosthetic group of a D-alanyl-carrier protein (DltC).
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Perego, M., Glaser, P., Minutello, A., Strauch, M.A., Leopold, K. and Fischer, W. Incorporation of D-alanine into lipoteichoic acid and wall teichoic acid in Bacillus subtilis. Identification of genes and regulation. J. Biol. Chem. 270 (1995) 15598–15606. [DOI] [PMID: 7797557]
2.  Yonus, H., Neumann, P., Zimmermann, S., May, J.J., Marahiel, M.A. and Stubbs, M.T. Crystal structure of DltA. Implications for the reaction mechanism of non-ribosomal peptide synthetase adenylation domains. J. Biol. Chem. 283 (2008) 32484–32491. [DOI] [PMID: 18784082]
3.  Du, L., He, Y. and Luo, Y. Crystal structure and enantiomer selection by D-alanyl carrier protein ligase DltA from Bacillus cereus. Biochemistry 47 (2008) 11473–11480. [DOI] [PMID: 18847223]
4.  Osman, K.T., Du, L., He, Y. and Luo, Y. Crystal structure of Bacillus cereus D-alanyl carrier protein ligase (DltA) in complex with ATP. J. Mol. Biol. 388 (2009) 345–355. [DOI] [PMID: 19324056]
[EC 6.2.1.54 created 2018]
 
 
EC 6.2.1.55
Accepted name: E1 SAMP-activating enzyme
Reaction: ATP + [SAMP]-Gly-Gly + [E1 SAMP-activating enzyme]-L-cysteine = S-[[SAMP]-Gly-Gly]-[[E1 SAMP-activating enzyme]-L-cysteine] + AMP + diphosphate (overall reaction)
(1a) ATP + [SAMP]-Gly-Gly = diphosphate + [SAMP]-Gly-Gly-AMP
(1b) [SAMP]-Gly-Gly-AMP + [E1 SAMP-activating enzyme]-L-cysteine = S-[[SAMP]-Gly-Gly]-[[E1 SAMP-activating enzyme]-L-cysteine] + AMP
Glossary: SAMP = small archaeal modifier protein = ubiquitin-like small archaeal modifier protein
Other name(s): UbaA; SAMP-activating enzyme E1
Systematic name: [SAMP]:[E1 SAMP-activating enzyme] ligase (AMP-forming)
Comments: Contains Zn2+. The enzyme catalyses the activation of SAMPs (Small Archaeal Modifier Proteins), which are ubiquitin-like proteins found only in the Archaea. SAMPs are involved in protein degradation, and also act as sulfur carriers involved in thiolation of tRNA and other metabolites such as molybdopterin. The enzyme catalyses the ATP-dependent formation of a SAMP adenylate intermediate in which the C-terminal glycine of SAMP is bound to AMP via an acyl-phosphate linkage (reaction 1). This intermediate can accept a sulfur atom to form a thiocarboxylate moiety in a mechanism that is not yet understood. Alternatively, the E1 enzyme can transfer SAMP from its activated form to an internal cysteine residue, releasing AMP (reaction 2). In this case SAMP is subsequently transferred to a lysine residue in a target protein in a process termed SAMPylation. Auto-SAMPylation (attachment of SAMP to lysine residues within the E1 enzyme) has been observed. cf. EC 2.7.7.100, SAMP-activating enzyme.
Links to other databases: BRENDA, EXPASY, IUBMB, KEGG
References:
1.  Miranda, H.V., Nembhard, N., Su, D., Hepowit, N., Krause, D.J., Pritz, J.R., Phillips, C., Soll, D. and Maupin-Furlow, J.A. E1- and ubiquitin-like proteins provide a direct link between protein conjugation and sulfur transfer in archaea. Proc. Natl Acad. Sci. USA 108 (2011) 4417–4422. [DOI] [PMID: 21368171]
2.  Maupin-Furlow, J.A. Ubiquitin-like proteins and their roles in archaea. Trends Microbiol 21 (2013) 31–38. [DOI] [PMID: 23140889]
3.  Miranda, H.V., Antelmann, H., Hepowit, N., Chavarria, N.E., Krause, D.J., Pritz, J.R., Basell, K., Becher, D., Humbard, M.A., Brocchieri, L. and Maupin-Furlow, J.A. Archaeal ubiquitin-like SAMP3 is isopeptide-linked to proteins via a UbaA-dependent mechanism. Mol. Cell. Proteomics 13 (2014) 220–239. [DOI] [PMID: 24097257]
4.  Hepowit, N.L., de Vera, I.M., Cao, S., Fu, X., Wu, Y., Uthandi, S., Chavarria, N.E., Englert, M., Su, D., Söll, D., Kojetin, D.J. and Maupin-Furlow, J.A. Mechanistic insight into protein modification and sulfur mobilization activities of noncanonical E1 and associated ubiquitin-like proteins of Archaea. FEBS J. 283 (2016) 3567–3586. [DOI] [PMID: 27459543]
[EC 6.2.1.55 created 2018]
 
 


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