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, Ron Caspi, Ture Damhus, Shinya Fushinobu, Julia Hauenstein, Antje Jäde, Ingrid Keseler, Masaaki Kotera, Andrew McDonald, Gerry Moss, 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 To prevent confusion please do not quote new EC numbers until they are incorporated into the main list.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 1.1.1.439 17-dehydrostemmadenine reductase
EC 1.1.1.440 rhazimal reductase
EC 1.3.1.127 vomilenine 19,20-reductase
EC 1.3.1.128 precondylocarpine acetate reductase
EC 1.5.1.56 3,17-didehydrostemmadenine reductase
EC 1.5.3.27 2-(methylaminoethyl)phosphonate oxidase
EC 1.13.11.94 4-vinylguaiacol dioxygenase
EC 1.14.14.186 tryptamine 5-hydroxylase
EC 1.14.14.187 rhazimal synthase
EC 1.14.15.40 cyclohexane-1-carboxylate 4-trans-hydroxylase
EC 1.14.19.80 (19E)-geissoschizine oxidase
EC 1.14.19.81 polyneuridine aldehyde synthase
EC 1.21.3.11 precondylocarpine acetate synthase
*EC 1.97.1.9 selenate reductase (cytochrome c)
EC 1.97.1.13 aliphatic sulfonate oxidoreductase
EC 1.97.1.14 selenate reductase (quinol)
EC 2.1.1.392 norajmaline N-methyltransferase
EC 2.1.1.393 ajmaline N-methyltransferase
EC 2.1.1.394 2-(S-pantetheinyl)-carbapenam-3-carboxylate methyltransferase
EC 2.1.1.395 7′-O-demethylcephaeline methyltransferase
EC 2.1.1.396 cephaeline 6′-O-methyltransferase
*EC 2.3.1.247 (5S)-5-amino-3-oxohexanoate:acetyl-CoA ethylamine transferase
EC 2.3.1.317 3-dehydrocarnitine:acetyl-CoA trimethylamine transferase
EC 2.3.1.318 3-oxoadipate:acetyl-CoA acetyltransferase
EC 2.3.1.319 3,5-dioxohexanoate:acetyl-CoA acetone transferase
EC 2.3.1.320 taxoid C-13 O-(3-amino-3-phenylpropanoyl)transferase
EC 2.3.1.321 3′-N-debenzoyltaxol N-benzoyltransferase
EC 2.3.1.322 akuammiline synthase
EC 2.3.1.323 stemmadenine O-acetyltransferase
EC 2.4.1.398 β-galactofuranoside β-1,5-galactofuranosyltransferase
EC 2.5.1.160 plant cystathionine γ-synthase
EC 2.7.11.38 NEK9 subfamily protein kinase
EC 2.7.11.39 ROCK-subfamily protein kinase
EC 3.1.3.111 decaprenylphosphoryl-5-phosphoribose phosphatase
EC 3.1.3.112 4′-phosphooxetanocin A phosphatase
EC 3.1.4.62 phosphatidylethanolamine phospholipase C
EC 3.13.2.4 lanthipeptide synthase
EC 4.1.1.128 UDP-N-acetyl-α-D-glucosaminuronate decarboxylase
EC 4.1.1.129 1′-carboxy-chondrochloren decarboxylase
EC 4.3.3.9 indigoidine synthase
EC 5.1.3.45 UDP-N-acetyl-α-D-glucosaminouronate 4-epimerase
EC 5.3.99.13 4′-phospho-dehydrooxetanocin synthase
EC 5.5.1.37 catharanthine synthase
EC 5.5.1.38 tabersonine synthase
EC 6.3.1.22 tRNAmet cytidine acetate ligase


EC 1.1.1.439 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 17-dehydrostemmadenine reductase
Reaction: stemmadenine + NADP+ = 17-dehydrostemmadenine + NADPH + H+
Other name(s): Redox2
Systematic name: stemmadenine:NADP+ 17-oxidoreductase
Comments: The enzyme, characterized from the plant Catharanthus roseus (Madagascar periwinkle), participates in a biosynthetic pathway that leads to production of the bisindole alkaloid compounds vinblastine and vincristine, which are used as anticancer drugs.
References:
1.  Qu, Y., Easson, M.EA.M., Simionescu, R., Hajicek, J., Thamm, A.MK., Salim, V. and De Luca, V. Solution of the multistep pathway for assembly of corynanthean, strychnos, iboga, and aspidosperma monoterpenoid indole alkaloids from 19E-geissoschizine. Proc. Natl. Acad. Sci. USA 115 (2018) 3180–3185. [DOI] [PMID: 29511102]
[EC 1.1.1.439 created 2024]
 
 
EC 1.1.1.440 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: rhazimal reductase
Reaction: rhazimol + NADP+ = rhazimal + NADPH + H+
Other name(s): AsRHR
Systematic name: rhazimol:NADP+ oxidoreductase (rhazimol-forming)
Comments: Isolated from the plant Alstonia scholaris (blackboard tree).
References:
1.  Wang, Z., Xiao, Y., Wu, S., Chen, J., Li, A. and Tatsis, E.C. Deciphering and reprogramming the cyclization regioselectivity in bifurcation of indole alkaloid biosynthesis. Chem. Sci. 13 (2022) 12389–12395. [DOI] [PMID: 36349266]
[EC 1.1.1.440 created 2024]
 
 
EC 1.3.1.127 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: vomilenine 19,20-reductase
Reaction: (20S)-19,20-dihydrovomilenine + NADP+ = vomilenine + NADPH + H+
Other name(s): RR4 (gene name); vomilenine reductase 2; VR2 (gene name)
Systematic name: (20S)-19,20-dihydrovomilenine:NADP+ 19,20-oxidoreductase
Comments: The enzyme has been charachterized from the plant Rauvolfia serpentina.
References:
1.  Geissler, M., Burghard, M., Volk, J., Staniek, A. and Warzecha, H. A novel cinnamyl alcohol dehydrogenase (CAD)-like reductase contributes to the structural diversity of monoterpenoid indole alkaloids in Rauvolfia. Planta 243 (2016) 813–824. [DOI] [PMID: 26715562]
[EC 1.3.1.127 created 2024]
 
 
EC 1.3.1.128 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: precondylocarpine acetate reductase
Reaction: dihydroprecondylocarpine acetate + NADP+ = precondylocarpine acetate + NADPH + H+
Other name(s): DPAS (gene name); dihydroprecondylocarpine acetate synthase
Systematic name: precondylocarpine acetate:NADP+ oxidoreductase
Comments: The enzyme, characterized from the plant Catharanthus roseus (Madagascar periwinkle), participates in a pathway that leads to the production of a number of monoterpene alkaloids, as well as the bisindole alkaloids vinblastine and vincristine, which are used as anticancer drugs. The enzyme forms the iminium ion form of dihydroprecondylocarpine acetate, which spontaneously rearranges and undergoes deacylation, producing dehydrosecodine.
References:
1.  Caputi, L., Franke, J., Farrow, S.C., Chung, K., Payne, R.ME., Nguyen, T.D., Dang, T.T., Soares Teto Carqueijeiro, I., Koudounas, K., Duge de Bernonville, T., Ameyaw, B., Jones, D.M., Vieira, I.JC., Courdavault, V. and O'Connor, S.E. Missing enzymes in the biosynthesis of the anticancer drug vinblastine in Madagascar periwinkle. Science 360 (2018) 1235–1239. [DOI] [PMID: 29724909]
2.  DeMars, M.D., 2nd and O'Connor, S.E. Evolution and diversification of carboxylesterase-like [4+2] cyclases in aspidosperma and iboga alkaloid biosynthesis. Proc. Natl. Acad. Sci. USA 121:e2318586121 (2024). [DOI] [PMID: 38319969]
[EC 1.3.1.128 created 2024]
 
 
EC 1.5.1.56 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 3,17-didehydrostemmadenine reductase
Reaction: 17-dehydrostemmadenine + NADP+ = 3,17-didehydrostemmadenine + NADPH + H+
Glossary: 3,17-didehydrostemmadenine = 3,4-didehydro-17-dehydrostemmadenine
Other name(s): Redox1
Systematic name: 17-dehydrostemmadenine:NADP+ 3(4)-oxidoreductase
Comments: The enzyme, characterized from the plant Catharanthus roseus (Madagascar periwinkle), participates in a biosynthetic pathway that leads to production of the bisindole alkaloid compounds vinblastine and vincristine, which are used as anticancer drugs. Both the substrate and the product of the enzyme are unstable.
References:
1.  Qu, Y., Easson, M.EA.M., Simionescu, R., Hajicek, J., Thamm, A.MK., Salim, V. and De Luca, V. Solution of the multistep pathway for assembly of corynanthean, strychnos, iboga, and aspidosperma monoterpenoid indole alkaloids from 19E-geissoschizine. Proc. Natl. Acad. Sci. USA 115 (2018) 3180–3185. [DOI] [PMID: 29511102]
[EC 1.5.1.56 created 2024]
 
 
EC 1.5.3.27 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 2-(methylaminoethyl)phosphonate oxidase
Reaction: 2-(methylaminoethyl)phosphonate + O2 + H2O = phosphonoacetaldehyde + methylamine + H2O2
Other name(s): pbfD (gene name); N-methyl-(2-aminoethyl)phosphonate oxidase
Systematic name: 2-(methylaminoethyl)phosphonate oxidase:oxygen oxidoreductase (phosphonoacetaldehyde-forming)
Comments: Contaions FAD. The enzyme also acts, with lower efficiency, on 2-aminoethylphosphonate, generating phosphonoacetaldehyde and ammonia. The enzyme from Acinetobacter baumannii also transformed 2-(dimethylaminoethyl)phosphonate with appreciable efficiency, generating dimethylamine in place of methylamine.
References:
1.  Zangelmi, E., Ruffolo, F., Dinhof, T., Gerdol, M., Malatesta, M., Chin, J.P., Rivetti, C., Secchi, A., Pallitsch, K. and Peracchi, A. Deciphering the role of recurrent FAD-dependent enzymes in bacterial phosphonate catabolism. iScience 26:108108 (2023). [DOI] [PMID: 37876809]
[EC 1.5.3.27 created 2024]
 
 
EC 1.13.11.94 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 4-vinylguaiacol dioxygenase
Reaction: (1) 4-vinylguaiacol + O2 = vanillin + formaldehyde
(2) 4-vinylphenol + O2 = 4-hydroxybenzaldehyde + formaldehyde
Glossary: 4-vinylguaiacol = 2-methoxy-4-vinylphenol
Other name(s): Ado; aromatic dioxygenase
Systematic name: 4-vinylguaiacol:oxygen oxidoreductase
Comments: The enzyme was isolated from the bacterium Caulobacter segnis and the fungus Thermothelomyces thermophilus. It is used as an economic option in lignin degradation since it does not require a cofactor.
References:
1.  Furuya, T., Miura, M. and Kino, K. A coenzyme-independent decarboxylase/oxygenase cascade for the efficient synthesis of vanillin. Chembiochem 15 (2014) 2248–2254. [DOI] [PMID: 25164030]
2.  Ni, J., Wu, Y.T., Tao, F., Peng, Y. and Xu, P. A coenzyme-free biocatalyst for the value-added utilization of lignin-derived aromatics. J. Am. Chem. Soc. 140 (2018) 16001–16005. [DOI] [PMID: 30376327]
[EC 1.13.11.94 created 2024]
 
 
EC 1.14.14.186 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: tryptamine 5-hydroxylase
Reaction: tryptamine + O2 + [reduced NADPH—hemoprotein reductase] = serotonin + H2O + [oxidized NADPH—hemoprotein reductase]
Glossary: serotonin = 5-hydroxytryptamine
Other name(s): CYP71P1 (gene name)
Systematic name: tryptamine,NADPH—hemoprotein reductase:oxygen oxidoreductase (5-hydroxylating)
Comments: A cytochrome P-450. The enzyme has been characterized from rice (Oryza sativa) and walnut (Juglans regia).
References:
1.  Schroder, P., Abele, C., Gohr, P., Stuhlfauth-Roisch, U. and Grosse, W. Latest on enzymology of serotonin biosynthesis in walnut seeds. Adv. Exp. Med. Biol. 467 (1999) 637–644. [DOI] [PMID: 10721112]
2.  Fujiwara, T., Maisonneuve, S., Isshiki, M., Mizutani, M., Chen, L., Wong, H.L., Kawasaki, T. and Shimamoto, K. Sekiguchi lesion gene encodes a cytochrome P450 monooxygenase that catalyzes conversion of tryptamine to serotonin in rice. J. Biol. Chem. 285 (2010) 11308–11313. [DOI] [PMID: 20150424]
3.  Park, S., Kang, K., Lee, S.W., Ahn, M.J., Bae, J.M. and Back, K. Production of serotonin by dual expression of tryptophan decarboxylase and tryptamine 5-hydroxylase in Escherichia coli. Appl. Microbiol. Biotechnol. 89 (2011) 1387–1394. [DOI] [PMID: 21080162]
4.  Park, S., Byeon, Y. and Back, K. Transcriptional suppression of tryptamine 5-hydroxylase, a terminal serotonin biosynthetic gene, induces melatonin biosynthesis in rice (Oryza sativa L.). J Pineal Res 55 (2013) 131–137. [DOI] [PMID: 23521226]
[EC 1.14.14.186 created 2024]
 
 
EC 1.14.14.187 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: rhazimal synthase
Reaction: geissoschizine + [reduced NADPH—hemoprotein reductase] + O2 = rhazimal + [oxidized NADPH—hemoprotein reductase] + 2 H2O
Other name(s): RHS (gene name)
Systematic name: geissoschizine,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (rhazimal forming)
Comments: A heme-thiolate protein (P-450) isolated from the plant Alstonia scholaris (blackboard tree).
References:
1.  Wang, Z., Xiao, Y., Wu, S., Chen, J., Li, A. and Tatsis, E.C. Deciphering and reprogramming the cyclization regioselectivity in bifurcation of indole alkaloid biosynthesis. Chem. Sci. 13 (2022) 12389–12395. [DOI] [PMID: 36349266]
[EC 1.14.14.187 created 2024]
 
 
EC 1.14.15.40 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: cyclohexane-1-carboxylate 4-trans-hydroxylase
Reaction: cyclohexane-1-carboxylate + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = trans-4-hydroxycyclohexane-1-carboxylate + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
Glossary: trans-4-hydroxycyclohexane-1-carboxylate = trans-4-hydroxycyclohexanecarboxylate
Other name(s): chcAa (gene name)
Systematic name: cyclohexane-1-carboxylate,ferredoxin:oxygen oxidoreductase (4-trans-hydroxylating)
Comments: The enzyme, characterized from the bacterium Corynebacterium cyclohexanicum, is a cytochrome P-450 enzyme that participates in the degradation pathway of cyclohexane-1-carboxylate. The initial source of the electrons is NADH, which transfers the electrons to a specific [2Fe-2S] ferredoxin via a dedicated EC 1.18.1.3, ferredoxin—NAD+ reductase.
References:
1.  Yamamoto, T., Hasegawa, Y., Lau, P.CK. and Iwaki, H. Identification and characterization of a chc gene cluster responsible for the aromatization pathway of cyclohexanecarboxylate degradation in Sinomonas cyclohexanicum ATCC 51369. J. Biosci. Bioeng. 132 (2021) 621–629. [DOI] [PMID: 34583900]
[EC 1.14.15.40 created 2024]
 
 
EC 1.14.19.80 – public review until 24 July 2024 [Last modified: 2024-06-28 08:05:35]
Accepted name: (19E)-geissoschizine oxidase
Reaction: (19E)-geissoschizine + O2 + [reduced NADPH-hemoprotein reductase] = akuammicine + formate + H2O + [oxidized NADPH-hemoprotein reductase] (overall reaction)
(1a) (19E)-geissoschizine + O2 + [reduced NADPH-hemoprotein reductase] = 3,17-didehydrostemmadenine + 2 H2O + [oxidized NADPH-hemoprotein reductase]
(1b) 3,17-didehydrostemmadenine = 17-dehydropreakuammicine (spontaneous)
(1c) 17-dehydropreakuammicine + H2O = 17-dehydropreakuammicine hydrate (spontaneous)
(1d) 17-dehydropreakuammicine hydrate = akuammicine + formate (spontaneous)
Glossary: (19E)-geissoschizine = methyl (16R,19E)-16-formylcoryn-19-en-17-oate
Other name(s): GO (gene name); CYP71D1V1 (gene name)
Systematic name: (19E)-geissoschizine,[reduced NADPH-hemoprotein reductase]:oxygen oxidoreductase (akuammicine-forming)
Comments: A cytochrome P-450 (heme-thiolate) enzyme characterized from the plant Catharanthus roseus (Madagascar periwinkle), that participates in the biosynthesis of a number of monoterpene alkaloids, as well as the bisindole alkaloids vinblastine and vincristine. The enzyme generates a nine-carbon ring that contains a nitrogen atom. The direct product of the enzyme, 3,17-didehydrostemmadenine, is unstable, and in the absence of other enzymes becomes akuammicine non-enzymically. However, in the presence of two dehydrogenases it is converted to stemmadenine via 17-dehydrostemmadenine.
References:
1.  Tatsis, E.C., Carqueijeiro, I., Duge de Bernonville, T., Franke, J., Dang, T.T., Oudin, A., Lanoue, A., Lafontaine, F., Stavrinides, A.K., Clastre, M., Courdavault, V. and O'Connor, S.E. A three enzyme system to generate the Strychnos alkaloid scaffold from a central biosynthetic intermediate. Nat. Commun. 8:316 (2017). [DOI] [PMID: 28827772]
2.  Qu, Y., Easson, M.EA.M., Simionescu, R., Hajicek, J., Thamm, A.MK., Salim, V. and De Luca, V. Solution of the multistep pathway for assembly of corynanthean, strychnos, iboga, and aspidosperma monoterpenoid indole alkaloids from 19E-geissoschizine. Proc. Natl. Acad. Sci. USA 115 (2018) 3180–3185. [DOI] [PMID: 29511102]
3.  Salim, V., Jarecki, S.A., Vick, M. and Miller, R. Advances in metabolic engineering of plant monoterpene indole alkaloids. Biology (Basel) 12 (2023) . [DOI] [PMID: 37626942]
[EC 1.14.19.80 created 2024]
 
 
EC 1.14.19.81 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: polyneuridine aldehyde synthase
Reaction: (19E)-geissoschizine + [oxidized NADPH—hemoprotein reductase] + O2 = polyneuridine aldehyde + [reduced NADPH—hemoprotein reductase] + 2 H2O
For diagram, click here
Other name(s): SBE (gene name); sarpagan bridge enzyme; CYP71AY4; CYP71AY5
Systematic name: (19E)-geissoschizine:[oxidized NADPH—hemoprotein reductase] oxidoreductase (polyneuridine aldehyde forming)
Comments: A heme-thiolate protein (P-450). The enzyme, characterized from the plants Rauwolfia serpentina (Indian snakeroot) and Gelsemium sempervirens (yellow jessamine), is involved in the biosynthesis of monoterpenoid indole alkaloids of the sarpagan, ajmalan and alstophyllan classes.
References:
1.  Dang, T.T., Franke, J., Carqueijeiro, I.ST., Langley, C., Courdavault, V. and O'Connor, S.E. Sarpagan bridge enzyme has substrate-controlled cyclization and aromatization modes. Nat. Chem. Biol. 14 (2018) 760–763. [DOI] [PMID: 29942076]
[EC 1.14.19.81 created 2024]
 
 
EC 1.21.3.11 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: precondylocarpine acetate synthase
Reaction: stemmadenine acetate + O2 = precondylocarpine acetate + H2O2
Other name(s): PAS (gene name)
Systematic name: stemmadenine acetate:oxygen oxidoreductase
Comments: The enzyme, characterized from the plant Catharanthus roseus (Madagascar periwinkle), participates in a pathway that leads to the production of a number of monoterpene alkaloids, as well as the bisindole alkaloids vinblastine and vincristine, which are used as anticancer drugs. The enzyme is similar to berberine bridge enzymes such as EC 1.21.3.3, reticuline oxidase, and requires an FAD cofactor.
References:
1.  Caputi, L., Franke, J., Farrow, S.C., Chung, K., Payne, R.ME., Nguyen, T.D., Dang, T.T., Soares Teto Carqueijeiro, I., Koudounas, K., Duge de Bernonville, T., Ameyaw, B., Jones, D.M., Vieira, I.JC., Courdavault, V. and O'Connor, S.E. Missing enzymes in the biosynthesis of the anticancer drug vinblastine in Madagascar periwinkle. Science 360 (2018) 1235–1239. [DOI] [PMID: 29724909]
[EC 1.21.3.11 created 2024]
 
 
*EC 1.97.1.9 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: selenate reductase (cytochrome c)
Reaction: 2 ferricytochrome c + selenite + H2O = 2 ferrocytochrome c + selenate
Other name(s): serA (gene name); serB (gene name); serC (gene name); selenite:reduced acceptor oxidoreductase; selenate reductase
Systematic name: ferricytochrome c:selenite oxidoreductase
Comments: The periplasmic enzyme from the bacterium Thauera selenatis is a complex comprising three heterologous subunits (α, β and γ) that contains a guanylyl molybdenum cofactor, as well as multiple iron-sulfur clusters and heme b. The enzyme reduces selenate to selenite using electrons provided by a diheme cytochrome c4, which receives the electrons from the membrane quinone pool via EC 7.1.1.8, quinol—cytochrome-c reductase. Nitrate, nitrite, chlorate and sulfate are not substrates.
Links to other databases: BRENDA, EXPASY, Gene, KEGG, MetaCyc, CAS registry number: 146359-71-9
References:
1.  Macy, J.M., Rech, S., Auling, G., Dorsch, M., Stackebrandt, E. and Sly, L.I. Thauera selenatis gen. nov., sp. nov., a member of the β subclass of Proteobacteria with a novel type of anaerobic respiration. Int. J. Syst. Bacteriol. 43 (1993) 135–142. [DOI] [PMID: 8427805]
2.  Schröder, I., Rech, S., Krafft, T. and Macy, J.M. Purification and characterization of the selenate reductase from Thauera selenatis. J. Biol. Chem. 272 (1997) 23765–23768. [DOI] [PMID: 9295321]
3.  Stolz, J.F. and Oremland, R.S. Bacterial respiration of arsenic and selenium. FEMS Microbiol. Rev. 23 (1999) 615–627. [DOI] [PMID: 10525169]
4.  Krafft, T., Bowen, A., Theis, F. and Macy, J.M. Cloning and sequencing of the genes encoding the periplasmic-cytochrome B-containing selenate reductase of Thauera selenatis. DNA 10 (2000) 365–377. [PMID: 10826693]
5.  Maher, M.J. and Macy, J.M. Crystallization and preliminary X-ray analysis of the selenate reductase from Thauera selenatis. Acta Crystallogr. D Biol. Crystallogr. 58 (2002) 706–708. [DOI] [PMID: 11914503]
6.  Maher, M.J., Santini, J., Pickering, I.J., Prince, R.C., Macy, J.M. and George, G.N. X-ray absorption spectroscopy of selenate reductase. Inorg. Chem. 43 (2004) 402–404. [DOI] [PMID: 14730999]
7.  Lowe, E.C., Bydder, S., Hartshorne, R.S., Tape, H.L., Dridge, E.J., Debieux, C.M., Paszkiewicz, K., Singleton, I., Lewis, R.J., Santini, J.M., Richardson, D.J. and Butler, C.S. Quinol-cytochrome c oxidoreductase and cytochrome c4 mediate electron transfer during selenate respiration in Thauera selenatis. J. Biol. Chem. 285 (2010) 18433–18442. [DOI] [PMID: 20388716]
[EC 1.97.1.9 created 2003, modified 2024]
 
 
EC 1.97.1.13 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: aliphatic sulfonate oxidoreductase
Reaction: an aliphatic sulfonate + 2 H2O + 4 oxidized ferredoxin = a carboxylate + sulfite + 4 reduced ferredoxin + 4 H+ (overall reaction)
(1a) an aliphatic sulfonate + H2O + 2 oxidized ferredoxin = an aldehyde + sulfite + 2 reduced ferredoxin + 2 H+
(1b) an aldehyde + H2O + 2 oxidized ferredoxin = a carboxylate + 2 reduced ferredoxin + 2 H+
Other name(s): WOR5; PF1479 (locus name); PF1480 (locus name)
Systematic name: aliphatic sulfonate:ferredoxin oxidoreductase (sulfite-releasing)
Comments: An oxygen-sensitive enzyme that contains tungsten-molybdopterin and iron-sulfur clusters, isolated the hyperthermophilic archaeon Pyrococcus furiosus. In that organism the enzyme is heterodimeric, comprising a catalytic subunit that contains the active site tungsto-bispyranopterin cofactor and a [4Fe-4S] cluster and an electron-transfer subunit that contains four additional [4Fe-4S] clusters. The activity involves two steps: an oxidative desulfonation reaction, followed by the activation of a second water molecule and oxidation of the resulting aldehyde (cf. EC 1.2.7.5, aldehyde ferredoxin oxidoreductase).
References:
1.  Mathew, L.G., Haja, D.K., Pritchett, C., McCormick, W., Zeineddine, R., Fontenot, L.S., Rivera, M.E., Glushka, J., Adams, M.WW. and Lanzilotta, W.N. An unprecedented function for a tungsten-containing oxidoreductase. J. Biol. Inorg. Chem. 27 (2022) 747–758. [DOI] [PMID: 36269456]
[EC 1.97.1.13 created 2024]
 
 
EC 1.97.1.14 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: selenate reductase (quinol)
Reaction: a quinone + selenite + H2O = a quinol + selenate
Other name(s): srdA (gene name); srdB (gene name); srdC (gene name)
Systematic name: quinone:selenite oxidoreductase
Comments: The enzyme, characterized from the bacterium Mesobacillus selenatarsenatis, is a membrane anchored type I molybdoenzyme. The enzyme is a complex comprising three heterologous subunits that contains a guanylyl molybdenum cofactor and multiple iron-sulfur clusters. The enzyme receives electrons directly from the membrane quinol pool and reduces selenate to selenite.
References:
1.  Ridley, H., Watts, C.A., Richardson, D.J. and Butler, C.S. Resolution of distinct membrane-bound enzymes from Enterobacter cloacae SLD1a-1 that are responsible for selective reduction of nitrate and selenate oxyanions. Appl. Environ. Microbiol. 72 (2006) 5173–5180. [DOI] [PMID: 16885262]
2.  Ma, J., Kobayashi, D.Y. and Yee, N. Role of menaquinone biosynthesis genes in selenate reduction by Enterobacter cloacae SLD1a-1 and Escherichia coli K12. Environ. Microbiol. 11 (2009) 149–158. [DOI] [PMID: 18811645]
3.  Kuroda, M., Yamashita, M., Miwa, E., Imao, K., Fujimoto, N., Ono, H., Nagano, K., Sei, K. and Ike, M. Molecular cloning and characterization of the srdBCA operon, encoding the respiratory selenate reductase complex, from the selenate-reducing bacterium Bacillus selenatarsenatis SF-1. J. Bacteriol. 193 (2011) 2141–2148. [DOI] [PMID: 21357486]
[EC 1.97.1.14 created 2024]
 
 
EC 2.1.1.392 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: norajmaline N-methyltransferase
Reaction: S-adenosyl-L-methionine + norajmaline = S-adenosyl-L-homocysteine + ajmaline
For diagram, click here
Other name(s): NNMT (gene name)
Systematic name: S-adenosyl-L-methionine:norajmaline N-methyltransferase
Comments: The enzyme, characterized from the plant Rauvolfia serpentina (Indian snakeroot), catalyses the last step in the pathway for the biosynthesis of the monoterpenoid indole alkaloid ajmaline. May also react with 17-O-acetylnorajmaline.
References:
1.  Cazares-Flores, P., Levac, D. and De Luca, V. Rauvolfia serpentina N-methyltransferases involved in ajmaline and Nβ-methylajmaline biosynthesis belong to a gene family derived from γ-tocopherol C-methyltransferase. Plant J. 87 (2016) 335–342. [DOI] [PMID: 27122470]
[EC 2.1.1.392 created 2024]
 
 
EC 2.1.1.393 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: ajmaline N-methyltransferase
Reaction: S-adenosyl-L-methionine + ajmaline = S-adenosyl-L-homocysteine + 4-methylajmaline
Glossary: 4-methylajmaline = Nβ-methylajmaline
Other name(s): RsANMT
Systematic name: S-adenosyl-L-methionine:ajmaline N-methyltransferase
Comments: Isolated from the plant Rauvolfia serpentina (Indian snakeroot). The enzyme can also methylate norajmaline, with lower activity.
References:
1.  Cazares-Flores, P., Levac, D. and De Luca, V. Rauvolfia serpentina N-methyltransferases involved in ajmaline and Nβ-methylajmaline biosynthesis belong to a gene family derived from γ-tocopherol C-methyltransferase. Plant J. 87 (2016) 335–342. [DOI] [PMID: 27122470]
[EC 2.1.1.393 created 2024]
 
 
EC 2.1.1.394 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 2-(S-pantetheinyl)-carbapenam-3-carboxylate methyltransferase
Reaction: (1) (2R,3R,5S)-2-(S-pantetheinyl)-carbapenam-3-carboxylate + 2 S-adenosyl-L-methionine + reduced acceptor = (2R,3R,5S,6R)-6-(methyl)-2-(S-pantetheinyl)-carbapenam-3-carboxylate + S-adenosyl-L-homocysteine + 5′-deoxyadenosine + L-methionine + acceptor
(2) (2R,3R,5S,6R)-6-(methyl)-2-(S-pantetheinyl)-carbapenam-3-carboxylate + 2 S-adenosyl-L-methionine + reduced acceptor = (2R,3R,5S,6R)-6-(ethyl)-2-(S-pantetheinyl)-carbapenam-3-carboxylate + S-adenosyl-L-homocysteine + 5′-deoxyadenosine + L-methionine + acceptor
Other name(s): thnK (gene name)
Systematic name: S-adenosyl-L-methionine:(2R,3R,5S)-2-(S-pantetheinyl)-carbapenam-3-carboxylate 6-C-methyltransferase
Comments: A radical SAM (AdoMet) enzyme that catalyses two consecutive methylations during the biosynthesis of complex carbapenem antibiotics. The enzyme adds a methyl group at position 6, followed by a second methylation that converts the methyl group to an ethyl group. The enzyme binds a [4Fe-4S] cluster and requires a cobalamin cofactor and an electron donor. Methyl viologen can be used in vitro.
References:
1.  Marous, D.R., Lloyd, E.P., Buller, A.R., Moshos, K.A., Grove, T.L., Blaszczyk, A.J., Booker, S.J. and Townsend, C.A. Consecutive radical S-adenosylmethionine methylations form the ethyl side chain in thienamycin biosynthesis. Proc. Natl. Acad. Sci. USA 112 (2015) 10354–10358. [DOI] [PMID: 26240322]
2.  Sinner, E.K. and Townsend, C.A. Purification and characterization of sequential cobalamin-dependent radical SAM methylases ThnK and TokK in carbapenem β-lactam antibiotic biosynthesis. Methods Enzymol. 669 (2022) 29–44. [DOI] [PMID: 35644176]
[EC 2.1.1.394 created 2024]
 
 
EC 2.1.1.395 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 7′-O-demethylcephaeline methyltransferase
Reaction: S-adenosyl-L-methionine + 7′-O-demethylcephaeline = S-adenosyl-L-homocysteine + cephaeline
Other name(s): IpeOMT2; CiOMT1
Systematic name: S-adenosyl-L-methionine:7′-O-demethylcephaeline 7′-O-methyltransferase
Comments: This activity is the penultimate step in the bionsynthesis of the alkaloid emetine. It is catalysed by two enzymes isolated from the roots of the tropical plant Carapichea ipecacuanha, IpeOMT2 and CiOMT1. The latter also catalyses the activity of EC 2.1.1.396, cephaeline 6′-O-methyltransferase, but with much lower activity.
References:
1.  Nomura, T. and Kutchan, T.M. Three new O-methyltransferases are sufficient for all O-methylation reactions of ipecac alkaloid biosynthesis in root culture of Psychotria ipecacuanha. J. Biol. Chem. 285 (2010) 7722–7738. [DOI] [PMID: 20061395]
2.  Cheong, B.E., Takemura, T., Yoshimatsu, K. and Sato, F. Molecular cloning of an O-methyltransferase from adventitious roots of Carapichea ipecacuanha. Biosci. Biotechnol. Biochem. 75 (2011) 107–113. [DOI] [PMID: 21228475]
[EC 2.1.1.395 created 2024]
 
 
EC 2.1.1.396 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: cephaeline 6′-O-methyltransferase
Reaction: S-adenosyl-L-methionine + cephaeline = S-adenosyl-L-homocysteine + emetine
Other name(s): IpeOMT1; CiOMT1
Systematic name: S-adenosyl-L-methionine:cephaeline 6′-O-methyltransferase
Comments: The enzyme IpeOMT1, isolated from the roots of the tropical plant Carapichea ipecacuanha, catalyses the final step in the bionsynthesis of the alkaloid emetine. A second enzyme isolated from the same plant, CiOMT1, also catalyses this activity, but catalyses the activity of EC 2.1.1.395, 7′-O-demethylcephaeline methyltransferase, with a much higher activity.
References:
1.  Nomura, T. and Kutchan, T.M. Three new O-methyltransferases are sufficient for all O-methylation reactions of ipecac alkaloid biosynthesis in root culture of Psychotria ipecacuanha. J. Biol. Chem. 285 (2010) 7722–7738. [DOI] [PMID: 20061395]
2.  Cheong, B.E., Takemura, T., Yoshimatsu, K. and Sato, F. Molecular cloning of an O-methyltransferase from adventitious roots of Carapichea ipecacuanha. Biosci. Biotechnol. Biochem. 75 (2011) 107–113. [DOI] [PMID: 21228475]
[EC 2.1.1.396 created 2024]
 
 
*EC 2.3.1.247 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: (5S)-5-amino-3-oxohexanoate:acetyl-CoA ethylamine transferase
Reaction: (5S)-5-amino-3-oxohexanoate + acetyl-CoA = acetoacetate + L-3-aminobutanoyl-CoA
For diagram of lysine catabolism, click here
Glossary: L-3-aminobutyryl-CoA = (3S)-3-aminobutanoyl-CoA
Other name(s): kce (gene name); 3-keto-5-aminohexanoate cleavage enzyme
Systematic name: (5S)-5-amino-3-oxohexanoate:acetyl-CoA ethylamine transferase
Comments: Requires Zn2+. The enzyme, isolated from the bacteria Fusobacterium nucleatum and Cloacimonas acidaminovorans, belongs to a class of enzymes known as β-keto acid cleavage enzymes (BKACE). It is involved in the anaerobic fermentation of lysine. cf. EC 2.3.1.317, 3-dehydrocarnitine:acetyl-CoA trimethylamine transferase, EC 2.3.1.318, 3-oxoadipate:acetyl-CoA acetyltransferase, and EC 2.3.1.319, 3,5-dioxohexanoate:acetyl-CoA acetone transferase.
Links to other databases: BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB
References:
1.  Barker, H.A., Kahn, J.M. and Hedrick, L. Pathway of lysine degradation in Fusobacterium nucleatum. J. Bacteriol. 152 (1982) 201–207. [PMID: 6811551]
2.  Kreimeyer, A., Perret, A., Lechaplais, C., Vallenet, D., Medigue, C., Salanoubat, M. and Weissenbach, J. Identification of the last unknown genes in the fermentation pathway of lysine. J. Biol. Chem. 282 (2007) 7191–7197. [DOI] [PMID: 17166837]
3.  Bellinzoni, M., Bastard, K., Perret, A., Zaparucha, A., Perchat, N., Vergne, C., Wagner, T., de Melo-Minardi, R.C., Artiguenave, F., Cohen, G.N., Weissenbach, J., Salanoubat, M. and Alzari, P.M. 3-Keto-5-aminohexanoate cleavage enzyme: a common fold for an uncommon Claisen-type condensation. J. Biol. Chem. 286 (2011) 27399–27405. [DOI] [PMID: 21632536]
[EC 2.3.1.247 created 2015, modified 2024]
 
 
EC 2.3.1.317 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 3-dehydrocarnitine:acetyl-CoA trimethylamine transferase
Reaction: 3-dehydrocarnitine + acetyl-CoA = acetoacetate + betainyl-CoA
Other name(s): cdhC (gene name); 3-dehydrocarnitine cleavage enzyme
Systematic name: 3-dehydrocarnitine:acetyl-CoA trimethylamine transferase
Comments: The enzyme, characterized from Pseudomonas aeruginosa and other bacteria, belongs to a class of enzymes known as β-keto acid cleavage enzymes (BKACE). It participates in an L-carnitine degradation pathway. cf. EC 2.3.1.247, (5S)-5-amino-3-oxohexanoate:acetyl-CoA ethylamine transferase, EC 2.3.1.318, 3-oxoadipate:acetyl-CoA acetyltransferase, and EC 2.3.1.319, 3,5-dioxohexanoate:acetyl-CoA acetone transferase.
References:
1.  Wargo, M.J. and Hogan, D.A. Identification of genes required for Pseudomonas aeruginosa carnitine catabolism. Microbiology (Reading) 155 (2009) 2411–2419. [DOI] [PMID: 19406895]
2.  Bastard, K., Smith, A.A., Vergne-Vaxelaire, C., Perret, A., Zaparucha, A., De Melo-Minardi, R., Mariage, A., Boutard, M., Debard, A., Lechaplais, C., Pelle, C., Pellouin, V., Perchat, N., Petit, J.L., Kreimeyer, A., Medigue, C., Weissenbach, J., Artiguenave, F., De Berardinis, V., Vallenet, D. and Salanoubat, M. Revealing the hidden functional diversity of an enzyme family. Nat. Chem. Biol. 10 (2014) 42–49. [DOI] [PMID: 24240508]
[EC 2.3.1.317 created 2024]
 
 
EC 2.3.1.318 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 3-oxoadipate:acetyl-CoA acetyltransferase
Reaction: 3-oxoadipate + acetyl-CoA = acetoacetate + succinyl-CoA
Glossary: 3-oxoadipate = β-ketoadipate = 3-oxohexanedioate
Other name(s): 3-oxoadipate cleavage enzyme
Systematic name: 3-oxoadipate:acetyl-CoA acetyltransferase
Comments: The enzyme, characterized from the bacteria Pseudomonas aeruginosa and Cupriavidus necator H16, belongs to a class of enzymes known as β-keto acid cleavage enzymes (BKACE). cf. EC 2.3.1.247, (5S)-5-amino-3-oxohexanoate:acetyl-CoA ethylamine transferase, EC 2.3.1.317, 3-dehydrocarnitine:acetyl-CoA trimethylamine transferase, and EC 2.3.1.319, 3,5-dioxohexanoate:acetyl-CoA acetone transferase.
References:
1.  Bastard, K., Smith, A.A., Vergne-Vaxelaire, C., Perret, A., Zaparucha, A., De Melo-Minardi, R., Mariage, A., Boutard, M., Debard, A., Lechaplais, C., Pelle, C., Pellouin, V., Perchat, N., Petit, J.L., Kreimeyer, A., Medigue, C., Weissenbach, J., Artiguenave, F., De Berardinis, V., Vallenet, D. and Salanoubat, M. Revealing the hidden functional diversity of an enzyme family. Nat. Chem. Biol. 10 (2014) 42–49. [DOI] [PMID: 24240508]
[EC 2.3.1.318 created 2024]
 
 
EC 2.3.1.319 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 3,5-dioxohexanoate:acetyl-CoA acetone transferase
Reaction: 3,5-dioxohexanoate + acetyl-CoA = acetoacetate + acetoacetyl-CoA
Other name(s): 3,5-dioxohexanoate cleavage enzyme
Systematic name: 3,5-dioxohexanoate:acetyl-CoA acetone transferase
Comments: The enzyme, characterized from fungus Blumeria graminis, belongs to a class of enzymes known as β-keto acid cleavage enzymes (BKACE). cf. EC 2.3.1.247, (5S)-5-amino-3-oxohexanoate:acetyl-CoA ethylamine transferase, EC 2.3.1.317, 3-dehydrocarnitine:acetyl-CoA trimethylamine transferase, and EC 2.3.1.318, 3-oxoadipate:acetyl-CoA acetyltransferase.
References:
1.  Bastard, K., Smith, A.A., Vergne-Vaxelaire, C., Perret, A., Zaparucha, A., De Melo-Minardi, R., Mariage, A., Boutard, M., Debard, A., Lechaplais, C., Pelle, C., Pellouin, V., Perchat, N., Petit, J.L., Kreimeyer, A., Medigue, C., Weissenbach, J., Artiguenave, F., De Berardinis, V., Vallenet, D. and Salanoubat, M. Revealing the hidden functional diversity of an enzyme family. Nat. Chem. Biol. 10 (2014) 42–49. [DOI] [PMID: 24240508]
[EC 2.3.1.319 created 2024]
 
 
EC 2.3.1.320 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: taxoid C-13 O-(3-amino-3-phenylpropanoyl)transferase
Reaction: baccatin III + (3R)-3-amino-3-phenylpropanoyl-CoA = 3′-N-debenzoyl-2′-deoxytaxol + CoA
Glossary: (3R)-3-amino-3-phenylpropanoyl-CoA = (3R)-β-phenylalanyl-CoA
Other name(s): BAPT; baccatin III:3-amino-3-phenylpropanoyltransferase; baccatin III-3-amino-13-phenylpropanoyltransferase; 3′-N-de-benzoyl-2′-deoxytaxol-N-benzoyltransferase
Systematic name: (3R)-3-amino-3-phenylpropanoyl-CoA:baccatin III C-13 O-((3R)-3-amino-3-phenylpropanoyl)transferase
Comments: The enzyme is active in the biosynthetic pathway of paclitaxel (Taxol) in Taxus species (yew)
References:
1.  Walker, K., Fujisaki, S., Long, R. and Croteau, R. Molecular cloning and heterologous expression of the C-13 phenylpropanoid side chain-CoA acyltransferase that functions in Taxol biosynthesis. Proc. Natl. Acad. Sci. USA 99 (2002) 12715–12720. [DOI] [PMID: 12232048]
[EC 2.3.1.320 created 2024]
 
 
EC 2.3.1.321 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 3′-N-debenzoyltaxol N-benzoyltransferase
Reaction: benzoyl-CoA + 3′-N-debenzoyltaxol = CoA + paclitaxel
Other name(s): DBTNBT; 3′-N-debenzoyl-2′-deoxytaxol N-benzoyltransferase
Systematic name: benzoyl-CoA:3′-N-debenzoyltaxol 3′-N-benzoyltransferase
Comments: The enzyme, present in Taxus species (yew) catalyses the final step in paclitaxel (Taxol) biosynthesis
References:
1.  Walker, K., Long, R. and Croteau, R. The final acylation step in taxol biosynthesis: cloning of the taxoid C13-side-chain N-benzoyltransferase from Taxus. Proc. Natl. Acad. Sci. USA 99 (2002) 9166–9171. [DOI] [PMID: 12089320]
2.  Long, R.M., Lagisetti, C., Coates, R.M. and Croteau, R.B. Specificity of the N-benzoyl transferase responsible for the last step of Taxol biosynthesis. Arch. Biochem. Biophys. 477 (2008) 384–389. [DOI] [PMID: 18621016]
3.  Zhang, Y., Wiese, L., Fang, H., Alseekh, S., Perez de Souza, L., Scossa, F., Molloy, J., Christmann, M. and Fernie, A.R. Synthetic biology identifies the minimal gene set required for paclitaxel biosynthesis in a plant chassis. Mol. Plant 16 (2023) 1951–1961. [DOI] [PMID: 37897038]
[EC 2.3.1.321 created 2024]
 
 
EC 2.3.1.322 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: akuammiline synthase
Reaction: acetyl-CoA + rhazimol = CoA + akuammiline
Other name(s): AsAKS1; AsAKS2
Systematic name: acetyl-CoA:rhazimol O-acetyltransferase
Comments: Isolated from the plant Alstonia scholaris (blackboard tree).
References:
1.  Wang, Z., Xiao, Y., Wu, S., Chen, J., Li, A. and Tatsis, E.C. Deciphering and reprogramming the cyclization regioselectivity in bifurcation of indole alkaloid biosynthesis. Chem. Sci. 13 (2022) 12389–12395. [DOI] [PMID: 36349266]
[EC 2.3.1.322 created 2024]
 
 
EC 2.3.1.323 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: stemmadenine O-acetyltransferase
Reaction: acetyl-CoA + stemmadenine = CoA + stemmadenine acetate
Other name(s): SAT (gene name)
Systematic name: acetyl-CoA:stemmadenine O-acetyltransferase
Comments: The enzyme, characterized from the plant Catharanthus roseus (Madagascar periwinkle), participates in a pathway that leads to the production of a number of monoterpene alkaloids, as well as the bisindole alkaloids vinblastine and vincristine, which are used as anticancer drugs.
References:
1.  Qu, Y., Easson, M.EA.M., Simionescu, R., Hajicek, J., Thamm, A.MK., Salim, V. and De Luca, V. Solution of the multistep pathway for assembly of corynanthean, strychnos, iboga, and aspidosperma monoterpenoid indole alkaloids from 19E-geissoschizine. Proc. Natl. Acad. Sci. USA 115 (2018) 3180–3185. [DOI] [PMID: 29511102]
[EC 2.3.1.323 created 2024]
 
 
EC 2.4.1.398 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: β-galactofuranoside β-1,5-galactofuranosyltransferase
Reaction: UDP-α-D-galactofuranose + a β-D-galactofuranoside = UDP + a β-D-Galf-(1→5)-β-D-galactofuranoside
Other name(s): gfsA (gene name); O-glycan β-1,5-galactofuranosyltransferase
Systematic name: UDP-α-D-galactofuranose:β-D-galactofuranoside β-1,5-galactofuranosyltransferase (configuration-inverting)
Comments: Requires Mn2+. The enzyme, characterized from the flilamentous fungi Aspergillus nidulans and Aspergillus fumigatus, participates in the synthesis of fungal-type galactomannan and O-mannose-type galactomannan, which are embedded in the fungal cell walls. While the reaction shown here describes the transfer of one galactofuransyl residue, the enzyme can add up to 5 more galactofuranosyl residues.
References:
1.  Komachi, Y., Hatakeyama, S., Motomatsu, H., Futagami, T., Kizjakina, K., Sobrado, P., Ekino, K., Takegawa, K., Goto, M., Nomura, Y. and Oka, T. GfsA encodes a novel galactofuranosyltransferase involved in biosynthesis of galactofuranose antigen of O-glycan in Aspergillus nidulans and Aspergillus fumigatus. Mol. Microbiol. 90 (2013) 1054–1073. [DOI] [PMID: 24118544]
2.  Katafuchi, Y., Li, Q., Tanaka, Y., Shinozuka, S., Kawamitsu, Y., Izumi, M., Ekino, K., Mizuki, K., Takegawa, K., Shibata, N., Goto, M., Nomura, Y., Ohta, K. and Oka, T. GfsA is a β1,5-galactofuranosyltransferase involved in the biosynthesis of the galactofuran side chain of fungal-type galactomannan in Aspergillus fumigatus. Glycobiology 27 (2017) 568–581. [DOI] [PMID: 28369326]
3.  Chihara, Y., Tanaka, Y., Izumi, M., Hagiwara, D., Watanabe, A., Takegawa, K., Kamei, K., Shibata, N., Ohta, K. and Oka, T. Biosynthesis of β-(1-→5)-Galactofuranosyl Chains of Fungal-Type and O-Mannose-Type Galactomannans within the Invasive Pathogen Aspergillus fumigatus. mSphere 5 (2020) . [DOI] [PMID: 31941812]
[EC 2.4.1.398 created 2024]
 
 
EC 2.5.1.160 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: plant cystathionine γ-synthase
Reaction: O-phospho-L-homoserine + L-cysteine = L-cystathionine + phosphate
Other name(s): CGS1 (gene name)
Systematic name: O-phospho-L-homoserine:L-cysteine S-(3-amino-3-carboxypropyl)transferase
Comments: A pyridoxal 5′-phosphate-dependent enzyme, found in plants, that participates in the plant L-methionine biosynthetic pathway. It differs from its bacterial counterpart, EC 2.5.1.48, cystathionine γ-synthase, in being specific for O-phospho-L-homoserine (the bacterial enzyme is specific for O-succinyl-L-homoserine).
References:
1.  Ravanel, S., Gakiere, B., Job, D. and Douce, R. Cystathionine γ-synthase from Arabidopsis thaliana: purification and biochemical characterization of the recombinant enzyme overexpressed in Escherichia coli. Biochem. J. 331 (1998) 639–648. [PMID: 9531508]
2.  Steegborn, C., Messerschmidt, A., Laber, B., Streber, W., Huber, R. and Clausen, T. The crystal structure of cystathionine γ-synthase from Nicotiana tabacum reveals its substrate and reaction specificity. J. Mol. Biol. 290 (1999) 983–996. [DOI] [PMID: 10438597]
3.  Clausen, T., Wahl, M.C., Messerschmidt, A., Huber, R., Fuhrmann, J.C., Laber, B., Streber, W. and Steegborn, C. Cloning, purification and characterisation of cystathionine γ-synthase from Nicotiana tabacum. Biol. Chem. 380 (1999) 1237–1242. [DOI] [PMID: 10595588]
[EC 2.5.1.160 created 2024]
 
 
EC 2.7.11.38 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: NEK9 subfamily protein kinase
Reaction: (1) ATP + [protein]-L-serine = ADP + [protein]-O-phospho-L-serine
(2) ATP + [protein]-L-threonine = ADP + [protein]-O-phospho-L-threonine
Other name(s): NEK9 subfamily kinase (misleading); serine/threonine-protein kinase Nek9; NEK9 (gene name); NERCC1 (gene name)
Systematic name: ATP:protein Ser/(Thr)-phosphotransferase (NEK9 subfamily)
Comments: This enzyme is found in animals and choanoflagellates, although it has been lost in arthropods and nematodes. It is implicated in centrosome separation [1] and cilium formation [6]. In peptide arrays, the enzyme prefers to phosphorylate Ser, with acidic residues at -2 and -4/-5, similar to that of the NEK6 protein kinase subfamily [4]. NEK9 can autophosphorylate. Substrates in humans include the microtubule-associated protein kinases NEK6/7 [1], the microtubule-associated protein spindle assembly protein TPX2 [3], the γ-tubulin associated protein NEDD1, which is required for mitotic spindle assembly and function [2] and the LC3B protein, which is involved in autophagy substrate selection and autophagosome biogenesis [5].
References:
1.  Bertran, M.T., Sdelci, S., Regue, L., Avruch, J., Caelles, C. and Roig, J. Nek9 is a Plk1-activated kinase that controls early centrosome separation through Nek6/7 and Eg5. EMBO J. 30 (2011) 2634–2647. [DOI] [PMID: 21642957]
2.  Sdelci, S., Schutz, M., Pinyol, R., Bertran, M.T., Regue, L., Caelles, C., Vernos, I. and Roig, J. Nek9 phosphorylation of NEDD1/GCP-WD contributes to Plk1 control of γ-tubulin recruitment to the mitotic centrosome. Curr. Biol. 22 (2012) 1516–1523. [DOI] [PMID: 22818914]
3.  Eibes, S., Gallisa-Sune, N., Rosas-Salvans, M., Martinez-Delgado, P., Vernos, I. and Roig, J. Nek9 Phosphorylation Defines a New Role for TPX2 in Eg5-Dependent Centrosome Separation before Nuclear Envelope Breakdown. Curr. Biol. 28 (2018) 121–129.e4. [DOI] [PMID: 29276125]
4.  van de Kooij, B., Creixell, P., van Vlimmeren, A., Joughin, B.A., Miller, C.J., Haider, N., Simpson, C.D., Linding, R., Stambolic, V., Turk, B.E. and Yaffe, M.B. Comprehensive substrate specificity profiling of the human Nek kinome reveals unexpected signaling outputs. Elife 8 (2019) . [DOI] [PMID: 31124786]
5.  Shrestha, B.K., Skytte Rasmussen, M., Abudu, Y.P., Bruun, J.A., Larsen, K.B., Alemu, E.A., Sjottem, E., Lamark, T. and Johansen, T. NIMA-related kinase 9-mediated phosphorylation of the microtubule-associated LC3B protein at Thr-50 suppresses selective autophagy of p62/sequestosome 1. J. Biol. Chem. 295 (2020) 1240–1260. [DOI] [PMID: 31857374]
6.  Yamamoto, Y., Chino, H., Tsukamoto, S., Ode, K.L., Ueda, H.R. and Mizushima, N. NEK9 regulates primary cilia formation by acting as a selective autophagy adaptor for MYH9/myosin IIA. Nat. Commun. 12:3292 (2021). [DOI] [PMID: 34078910]
[EC 2.7.11.38 created 2022]
 
 
EC 2.7.11.39 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: ROCK-subfamily protein kinase
Reaction: (1) ATP + [protein]-L-serine = ADP + [protein]-O-phospho-L-serine
(2) ATP + [protein]-L-threonine = ADP + [protein]-O-phospho-L-threonine
The enzyme has wide range known substrates, mostly involved in cytoskeletal regulation, with a preference for positive charges at P1 to P5.
Other name(s): ROCK; Rho Kinase; ROCK1; ROCK2; rok; let-402; ROCK-I (gene name); ROCK-II (gene name)
Systematic name: ATP:cytoskeleton-protein phosphotransferase
Comments: Requires Mg2+. An animal specific kinase that is duplicated in vertebrates (ROCK1, ROCK2), and with homologs in Drosophila (rok) and Caenorhabditis elegans (let-502). They are ~1300 amino-acid proteins, with an N-terminal kinase domain, with the AGC-specific kinase domain tail, followed by a central coiled-coil region, HR1 domain, Rho-binding domain (RBD), and PH domain. The PH domain is split by an inserted CRD (cysteine-rich Zn finger motif). ROCK is activated by the small GTPase Rho and modulates the cytoskeleton by phosphorylation of a wide array of other cytoskeletal proteins. Binding of Rho-GTP to the RBD relieves an intramolecular inhibition and activates the kinase activity. These kinases modulate the cytoskeleton in response to Rho GTPase signalling. Substrates include LIM-kinase (LIMK) which phosphorylates and inhibits cofilin, blocking its actin-depolymerizing function [1], and myosin regulatory light chain (MRLC2/MYL12B) in that regulates Myosin II. In Drosophila is involve in the planar cell polarity pathway, where it is genetically downstream of frizzled and dishevelled gene families, and phosphorylates the non-muscle myosin light chain, regulating Myosin II [2]. It is activated by Rho1, the single homolog of human RhoA/B/C, which also activate ROCK.
References:
1.  Ohashi, K., Nagata, K., Maekawa, M., Ishizaki, T., Narumiya, S. and Mizuno, K. Rho-associated kinase ROCK activates LIM-kinase 1 by phosphorylation at threonine 508 within the activation loop. J. Biol. Chem. 275 (2000) 3577–3582. [DOI] [PMID: 10652353]
2.  Winter, C.G., Wang, B., Ballew, A., Royou, A., Karess, R., Axelrod, J.D. and Luo, L. Drosophila Rho-associated kinase (Drok) links Frizzled-mediated planar cell polarity signaling to the actin cytoskeleton. Cell 105 (2001) 81–91. [DOI] [PMID: 11301004]
[EC 2.7.11.39 created 2024]
 
 
EC 3.1.3.111 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: decaprenylphosphoryl-5-phosphoribose phosphatase
Reaction: trans,octacis-decaprenylphospho-β-D-ribofuranose 5-phosphate + H2O = trans,octacis-decaprenylphospho-β-D-ribofuranose + phosphate
Other name(s): Rv3807c (gene name)
Systematic name: trans,octacis-decaprenylphospho-β-D-ribofuranose 5-phosphate phosphohydrolase
Comments: The enzyme, studied from mycobacteria, in involved in the biosynthesis of trans,octacis-decaprenylphospho-β-D-arabinofuranose, which serves in those organisms as the arabinofuranose donor for the biosynthesis of the cell wall polymers arabinogalactan and lipoarabinomannan.
References:
1.  Wolucka, B.A. Biosynthesis of D-arabinose in mycobacteria - a novel bacterial pathway with implications for antimycobacterial therapy. FEBS J. 275 (2008) 2691–2711. [DOI] [PMID: 18422659]
2.  Jiang, T., Cai, L., Zhao, X., He, L., Ma, Y., Zang, S., Zhang, C., Li, X. and Xin, Y. Functional identification of MSMEG_6402 protein from Mycobacterium smegmatis in decaprenylphosphoryl-D-arabinose biosynthesis. Microb Pathog 76 (2014) 44–50. [DOI] [PMID: 25223716]
[EC 3.1.3.111 created 2024]
 
 
EC 3.1.3.112 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 4′-phosphooxetanocin A phosphatase
Reaction: 4′-phosphooxetanocin A + H2O = oxetanocin A + phosphate
Glossary: 4′-phosphooxetanocin A = [(2S,3R,4R)-4-(6-aminopurin-9-yl)-3-(hydroxymethyl)oxetan-2-yl]methyl phosphate
Other name(s): oxsA (gene name)
Systematic name: [(2S,3R,4R)-4-(6-aminopurin-9-yl)-3-(hydroxymethyl)oxetan-2-yl]methyl phosphate phosphohydrolase
Comments: The enzyme can catalyse the sequential hydrolysis of tri-, di-, and mono-phosphorylated oxetanocin A compounds, releasing one molecule of inorganic phosphate at a time. The active site switches from a dinuclear to a mononuclear metal center as phosphates are eliminated from the substrate.
References:
1.  Bridwell-Rabb, J., Zhong, A., Sun, H.G., Drennan, C.L. and Liu, H.W. A B12-dependent radical SAM enzyme involved in oxetanocin A biosynthesis. Nature 544 (2017) 322–326. [DOI] [PMID: 28346939]
[EC 3.1.3.112 created 2024]
 
 
EC 3.1.4.62 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: phosphatidylethanolamine phospholipase C
Reaction: a phosphatidylethanolamine + H2O = a 1,2-diacyl-sn-glycerol + O-phosphoethanolamine
Other name(s): phosphatidylethanolamine-specific phospholipase C; PE-PLC; SMSr; SAMD8 (gene name); SMS1 (gene name)
Systematic name: phosphatidylethanolamine ethanolaminephosphohydrolase
Comments: This activity, which is similar to that of EC 3.1.4.3, phospholipase C, has been characterized from mammalian cells [1-4]. Multiple enzymes have been shown to catalyse this activity, including human sphingomyelin synthase-related protein (SMSr, gene name; SAMD8) [6-8] and sphingomyelin synthase 1 (SMS1, gene name; SGMS1) [9] (cf. EC 2.7.8.27, sphingomyelin synthase).
References:
1.  Hafez, M.M. and Costlow, M.E. Phosphatidylethanolamine turnover is an early event in the response of NB2 lymphoma cells to prolactin. Exp. Cell Res. 184 (1989) 37–43. [DOI] [PMID: 2507337]
2.  Kiss, Z. and Anderson, W.B. ATP stimulates the hydrolysis of phosphatidylethanolamine in NIH 3T3 cells. Potentiating effects of guanosine triphosphates and sphingosine. J. Biol. Chem. 265 (1990) 7345–7350. [PMID: 2185245]
3.  Kiss, Z., Crilly, K. and Chattopadhyay, J. Ethanol potentiates the stimulatory effects of phorbol ester, sphingosine and 4-hydroxynonenal on the hydrolysis of phosphatidylethanolamine in NIH 3T3 cells. Eur. J. Biochem. 197 (1991) 785–790. [DOI] [PMID: 2029907]
4.  Kiss, Z. The long-term combined stimulatory effects of ethanol and phorbol ester on phosphatidylethanolamine hydrolysis are mediated by a phospholipase C and prevented by overexpressed α-protein kinase C in fibroblasts. Eur. J. Biochem. 209 (1992) 467–473. [DOI] [PMID: 1327780]
5.  Kiss, Z. and Tomono, M. Compound D609 inhibits phorbol ester-stimulated phospholipase D activity and phospholipase C-mediated phosphatidylethanolamine hydrolysis. Biochim. Biophys Acta 1259 (1995) 105–108. [DOI] [PMID: 7492608]
6.  Murakami, C. and Sakane, F. Sphingomyelin synthase-related protein generates diacylglycerol via the hydrolysis of glycerophospholipids in the absence of ceramide. J. Biol. Chem. 296:100454 (2021). [DOI] [PMID: 33621517]
7.  Chiang, Y.P., Li, Z., Chen, Y., Cao, Y. and Jiang, X.C. Sphingomyelin synthase related protein is a mammalian phosphatidylethanolamine phospholipase C. Biochim Biophys Acta Mol Cell Biol Lipids 1866:159017 (2021). [DOI] [PMID: 34332077]
8.  Hu, K., Zhang, Q., Chen, Y., Yang, J., Xia, Y., Rao, B., Li, S., Shen, Y., Cao, M., Lu, H., Qin, A., Jiang, X.C., Yao, D., Zhao, J., Zhou, L. and Cao, Y. Cryo-EM structure of human sphingomyelin synthase and its mechanistic implications for sphingomyelin synthesis. Nat. Struct. Mol. Biol. (2024) . [DOI] [PMID: 38388831]
9.  Suzuki, R., Murakami, C., Dilimulati, K., Atsuta-Tsunoda, K., Kawai, T. and Sakane, F. Human sphingomyelin synthase 1 generates diacylglycerol in the presence and absence of ceramide via multiple enzymatic activities. FEBS Lett. 597 (2023) 2672–2686. [DOI] [PMID: 37715942]
[EC 3.1.4.62 created 2024]
 
 
EC 3.13.2.4 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: lanthipeptide synthase
Reaction: (1) a [protein]-L-serine + a [protein]-L-cysteine = a [protein] with lanthionine crosslink + H2O (overall reaction)
(1a) a [protein]-L-serine = a [protein]-2-aminoprop-2-enoate + H2O
(1b) a [protein]-2-aminoprop-2-enoate + a [protein]-L-cysteine = a [protein] with lanthionine crosslink
(2) a [protein]-L-threonine + a [protein]-L-cysteine = a [protein] with 3-methyllanthionine crosslink + H2O (overall reaction)
(2a) a [protein]-L-threonine = a [protein]-(Z)-2-aminobutenoate + H2O
(2b) a [protein]-(Z)-2-aminobutenoate + a [protein]-L-cysteine = a [protein] with 3-methyllanthionine crosslink
Other name(s): lanthipeptide synthetase
Systematic name: [protein]-(methyl)lanthionine hydrolase
Comments: The lanthipeptides are a family of ribosomally synthesized and post-translationally modified peptides (RiPPs) that is characterized by the presence of multiple lanthionine (Lan) and 3-methyllanthionine (MeLan) crosslinks, which are formed by lanthipeptide synthases. These enzymes catalyse dehydration of Ser/Thr residues, followed by intramolecular addition of the thiol group of a Cys residue to the dehydro amino acids, which results in the formation of the thioether crosslinks of (methyl)lanthionine.
References:
1.  Li, B., Yu, J.P., Brunzelle, J.S., Moll, G.N., van der Donk, W.A. and Nair, S.K. Structure and mechanism of the lantibiotic cyclase involved in nisin biosynthesis. Science 311 (2006) 1464–1467. [DOI] [PMID: 16527981]
2.  Willey, J.M. and van der Donk, W.A. Lantibiotics: peptides of diverse structure and function. Annu. Rev. Microbiol. 61 (2007) 477–501. [DOI] [PMID: 17506681]
3.  Li, B. and van der Donk, W.A. Identification of essential catalytic residues of the cyclase NisC involved in the biosynthesis of nisin. J. Biol. Chem. 282 (2007) 21169–21175. [DOI] [PMID: 17513866]
4.  Goto, Y., Li, B., Claesen, J., Shi, Y., Bibb, M.J. and van der Donk, W.A. Discovery of unique lanthionine synthetases reveals new mechanistic and evolutionary insights. PLoS Biol. 8:e1000339 (2010). [DOI] [PMID: 20351769]
5.  Zhang, Q., Yu, Y., Velasquez, J.E. and van der Donk, W.A. Evolution of lanthipeptide synthetases. Proc. Natl. Acad. Sci. USA 109 (2012) 18361–18366. [DOI] [PMID: 23071302]
[EC 3.13.2.4 created 2024]
 
 
EC 4.1.1.128 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: UDP-N-acetyl-α-D-glucosaminuronate decarboxylase
Reaction: UDP-N-acetyl-α-D-glucosaminuronate = UDP-N-acety-α-D-xylosamine + CO2
Other name(s): UXNAcS; DP-XylNAc synthase
Systematic name: UDP-N-acetyl-α-D-glucosaminuronate carboxy-lyase
Comments: The enzyme has been described from pathogenic Bacillus species, including Bacillus anthracis, Bacillus thuringiensis, and Bacillus cereus. The enzyme requires an NAD cofactor, and the reaction proceeds via a 4-dehydro intermediate, resulting in reduction of NAD+ to NADH (cf. EC 1.1.1.305, UDP-glucuronic acid dehydrogenase (UDP-4-keto-hexauronic acid decarboxylating)). However, NADH is not released from the enzyme and is recycled back to NAD+ at the completion of the reaction cycle. The product is incorporated into an extracellular polysaccharide known as pzX.
References:
1.  Gu, X., Glushka, J., Lee, S.G. and Bar-Peled, M. Biosynthesis of a new UDP-sugar, UDP-2-acetamido-2-deoxyxylose, in the human pathogen Bacillus cereus subspecies cytotoxis NVH 391-98. J. Biol. Chem. 285 (2010) 24825–24833. [DOI] [PMID: 20529859]
2.  Li, Z., Hwang, S. and Bar-Peled, M. Discovery of a Unique Extracellular Polysaccharide in Members of the Pathogenic Bacillus That Can Co-form with Spores. J. Biol. Chem. 291 (2016) 19051–19067. [DOI] [PMID: 27402849]
[EC 4.1.1.128 created 2024]
 
 
EC 4.1.1.129 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 1′-carboxy-chondrochloren decarboxylase
Reaction: (1) 1′-carboxy-chondrochloren A + FAD = chondrochloren A + CO2 + FADH2
(2) 1′-carboxy-chondrochloren B + FAD = chondrochloren B + CO2 + FADH2
Glossary: chondrochloren A = (2R,3R,4R,5E,8S,9S,10R)-N-[(Z)-2-(3-chloro-4-hydroxyphenyl)ethenyl]-3,9-dihydroxy-2,4-dimethoxy-6,8,10-trimethyl-7-oxotetradec-5-enamide
chondrochloren B = (2R,3R,4R,5E,8S,9S,10R)-N-[(Z)-2-(3-chloro-4-hydroxyphenyl)ethenyl]-2-ethoxy-3,9-dihydroxy-4-methoxy-6,8,10-trimethyl-7-oxotetradec-5-enamide
Other name(s): cndG (gene name)
Systematic name: 1′-carboxy-chondrochloren carboxy-lyase
Comments: The enzyme, characterized from the bacterium Chondromyces crocatus, catalyses the final reactions in the biosynthesis of the antibiotics chondrochloren A andchondrochloren B.
References:
1.  Rachid, S., Revermann, O., Dauth, C., Kazmaier, U. and Muller, R. Characterization of a novel type of oxidative decarboxylase involved in the biosynthesis of the styryl moiety of chondrochloren from an acylated tyrosine. J. Biol. Chem. 285 (2010) 12482–12489. [DOI] [PMID: 20080978]
[EC 4.1.1.129 created 2024]
 
 
EC 4.3.3.9 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: indigoidine synthase
Reaction: 2 ATP + 2 L-glutamine + O2 + 2 FMN = 2 AMP + 2 diphosphate + indigoidine + 2 H2O + 2 FMNH2 (overall reaction)
(1) 2 ATP + 2 L-glutamine + 2 FMN = 2 AMP + 2 diphosphate + 2 3-amino-1,5-dihydropyridine-2,6-dione + FMNH2
(2) 2 3-amino-1,5-dihydropyridine-2,6-dione + O2 = indigoidine + 2 H2O (spontaneous)
Glossary: indigoidine = 3-(5-amino-2-hydroxy-6-oxo-1H-pyridin-3-yl)-5-iminopyridine-2,6-dione
Other name(s): bspA (gene name)
Systematic name: L-glutamine oxidoreductase/cyclase (3-amino-1,5-dihydropyridine-2,6-dione-forming)
Comments: The enzyme, found in a number of bacterial strains, is a non-ribosomal peptide synthase (NRPS). The enzyme forms 3-amino-1,5-dihydropyridine-2,6-dione, which undergoes spontaneous oxidation to form the blue pigment indigoidine.
References:
1.  Reverchon, S., Rouanet, C., Expert, D. and Nasser, W. Characterization of indigoidine biosynthetic genes in Erwinia chrysanthemi and role of this blue pigment in pathogenicity. J. Bacteriol. 184 (2002) 654–665. [DOI] [PMID: 11790734]
2.  Takahashi, H., Kumagai, T., Kitani, K., Mori, M., Matoba, Y. and Sugiyama, M. Cloning and characterization of a Streptomyces single module type non-ribosomal peptide synthetase catalyzing a blue pigment synthesis. J. Biol. Chem. 282 (2007) 9073–9081. [DOI] [PMID: 17237222]
3.  Walsh, C.T. and Wencewicz, T.A. Flavoenzymes: versatile catalysts in biosynthetic pathways. Nat. Prod. Rep. 30 (2013) 175–200. [DOI] [PMID: 23051833]
[EC 4.3.3.9 created 2024]
 
 
EC 5.1.3.45 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: UDP-N-acetyl-α-D-glucosaminouronate 4-epimerase
Reaction: UDP-N-acetyl-α-D-glucosaminouronate = UDP-N-acetyl-α-D-galactosaminouronate
Other name(s): tviC (gene name); wbpP (gene name); UDP-N-acetylglucosaminuronic acid 4-epimerase
Systematic name: UDP-N-acetyl-α-D-glucosaminouronate 4-epimerase
Comments: The enzyme is found in bacteria and participates in the biosynthesis of assorted bacterial lipopolysaccharides and capsular polysaccharides. It contains a tightly-bound NAD(H) cofactor. The enzyme also catalyses the activity of EC 5.1.3.7, UDP-N-acetylglucosamine 4-epimerase, with lower efficiency.
References:
1.  Ishiyama, N., Creuzenet, C., Lam, J.S. and Berghuis, A.M. Crystal structure of WbpP, a genuine UDP-N-acetylglucosamine 4-epimerase from Pseudomonas aeruginosa: substrate specificity in udp-hexose 4-epimerases. J. Biol. Chem. 279 (2004) 22635–22642. [DOI] [PMID: 15016816]
2.  Zhang, H., Zhou, Y., Bao, H. and Liu, H.W. Vi antigen biosynthesis in Salmonella typhi: characterization of UDP-N-acetylglucosamine C-6 dehydrogenase (TviB) and UDP-N-acetylglucosaminuronic acid C-4 epimerase (TviC). Biochemistry 45 (2006) 8163–8173. [DOI] [PMID: 16800641]
3.  Miller, W.L., Matewish, M.J., McNally, D.J., Ishiyama, N., Anderson, E.M., Brewer, D., Brisson, J.R., Berghuis, A.M. and Lam, J.S. Flagellin glycosylation in Pseudomonas aeruginosa PAK requires the O-antigen biosynthesis enzyme WbpO. J. Biol. Chem. 283 (2008) 3507–3518. [DOI] [PMID: 18065759]
[EC 5.1.3.45 created 2024]
 
 
EC 5.3.99.13 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: 4′-phospho-dehydrooxetanocin synthase
Reaction: dAMP + S-adenosyl-L-methionine = 4′-phospho-dehydrooxetanocin + 5′-deoxyadenosine + L-methionine (overall reaction)
(1a) S-adenosyl-L-methionine + reduced acceptor = 5′-deoxyadenosin-5′-yl radical + L-methionine + acceptor
(1b) 5′-deoxyadenosin-5′-yl radical + dAMP + acceptor = 4′-phospho-dehydrooxetanocin + 5′-deoxyadenosine + reduced acceptor
Glossary: oxetanocin A = [(2S,3R,4R)-4-(6-amino-9H-purin-9-yl)oxetane-2,3-diyl]dimethanol
Other name(s): oxsB (gene name)
Systematic name: dAMP isomerase (4′-phospho-dehydrooxetanocin-forming)
Comments: The enzyme is a B12-dependent radical SAM (AdoMet) enzyme involved in the biosynthesis of oxetanocin A. The enzyme catalyses an oxidative ring contraction, forming an oxetane aldehyde. The reaction requires S-adenosyl-L-methionine, a cobalamin cofactor, and a reductant (the reductant does not show in the overall reaction because it is being restored during the cycle). The reaction is initiated by formation of 5′-deoxyadenosin-5′-yl radical, which then abstracts a hydrogen atom from C2′. The enzyme is also able to catalyse the radical mediated, stereoselective C2′-methylation of dAMP.
References:
1.  Bridwell-Rabb, J., Zhong, A., Sun, H.G., Drennan, C.L. and Liu, H.W. A B12-dependent radical SAM enzyme involved in oxetanocin A biosynthesis. Nature 544 (2017) 322–326. [DOI] [PMID: 28346939]
2.  Lee, Y.H., Yeh, Y.C., Fan, P.H., Zhong, A., Ruszczycky, M.W. and Liu, H.W. Changing Fates of the Substrate Radicals Generated in the Active Sites of the B12-Dependent Radical SAM Enzymes OxsB and AlsB. J. Am. Chem. Soc. 145 (2023) 3656–3664. [DOI] [PMID: 36719327]
[EC 5.3.99.13 created 2024]
 
 
EC 5.5.1.37 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: catharanthine synthase
Reaction: dehydrosecodine = catharanthine
Other name(s): CS (gene name)
Systematic name: dehydrosecodine cyclase (catharanthine-forming)
Comments: The enzyme, characterized from the plant Catharanthus roseus (Madagascar periwinkle), is a carboxylesterase-like cyclase that catalyses a regio- and enantiodivergent [4+2] cycloaddition reaction to generate the iboga scaffold of catharanthine. cf. EC 5.5.1.38, tabersonine synthase.
References:
1.  Caputi, L., Franke, J., Farrow, S.C., Chung, K., Payne, R.ME., Nguyen, T.D., Dang, T.T., Soares Teto Carqueijeiro, I., Koudounas, K., Duge de Bernonville, T., Ameyaw, B., Jones, D.M., Vieira, I.JC., Courdavault, V. and O'Connor, S.E. Missing enzymes in the biosynthesis of the anticancer drug vinblastine in Madagascar periwinkle. Science 360 (2018) 1235–1239. [DOI] [PMID: 29724909]
2.  DeMars, M.D., 2nd and O'Connor, S.E. Evolution and diversification of carboxylesterase-like [4+2] cyclases in aspidosperma and iboga alkaloid biosynthesis. Proc. Natl. Acad. Sci. USA 121:e2318586121 (2024). [DOI] [PMID: 38319969]
[EC 5.5.1.37 created 2024]
 
 
EC 5.5.1.38 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: tabersonine synthase
Reaction: dehydrosecodine = tabersonine
Other name(s): TS (gene name)
Systematic name: dehydrosecodine cyclase (tabersonine-forming)
Comments: The enzyme, characterized from the plant Catharanthus roseus (Madagascar periwinkle), is a carboxylesterase-like cyclase that catalyses a regio- and enantiodivergent [4+2] cycloaddition reaction to generate the aspidosperma scaffold of tabersonine. cf. EC 5.5.1.37, catharanthine synthase.
References:
1.  Caputi, L., Franke, J., Farrow, S.C., Chung, K., Payne, R.ME., Nguyen, T.D., Dang, T.T., Soares Teto Carqueijeiro, I., Koudounas, K., Duge de Bernonville, T., Ameyaw, B., Jones, D.M., Vieira, I.JC., Courdavault, V. and O'Connor, S.E. Missing enzymes in the biosynthesis of the anticancer drug vinblastine in Madagascar periwinkle. Science 360 (2018) 1235–1239. [DOI] [PMID: 29724909]
2.  DeMars, M.D., 2nd and O'Connor, S.E. Evolution and diversification of carboxylesterase-like [4+2] cyclases in aspidosperma and iboga alkaloid biosynthesis. Proc. Natl. Acad. Sci. USA 121:e2318586121 (2024). [DOI] [PMID: 38319969]
[EC 5.5.1.38 created 2024]
 
 
EC 6.3.1.22 – public review until 24 July 2024 [Last modified: 2024-06-26 15:31:21]
Accepted name: tRNAmet cytidine acetate ligase
Reaction: ATP + [elongator tRNAMet]-cytidine34 + acetate = AMP + diphosphate + [elongator tRNAMet]-N4-acetylcytidine34 (overall reaction)
(1a) ATP + acetate = acetyladenylate + diphosphate
(1b) acetyladenylate + [elongator tRNAMet]-cytidine34 = AMP + [elongator tRNAMet]-N4-acetylcytidine34
Other name(s): tmcAL (gene name)
Systematic name: elongator tRNAmet cytidine:acetate ligase (AMP-forming)
Comments: The enzyme, charactrized from the bacterium Bacillus subtilis, catalyses a similar tRNA modification to that performed by EC 2.3.1.193, tRNAMet cytidine acetyltransferase. However, unlike that enzyme, which uses acetyl-CoA as the acetyl donor, this enzyme activates an acetate ion to form acetyladenylate and then catalyses the acetylation through a mechanism similar to tRNA aminoacylation.
References:
1.  Taniguchi, T., Miyauchi, K., Sakaguchi, Y., Yamashita, S., Soma, A., Tomita, K. and Suzuki, T. Acetate-dependent tRNA acetylation required for decoding fidelity in protein synthesis. Nat. Chem. Biol. 14 (2018) 1010–1020. [DOI] [PMID: 30150682]
[EC 6.3.1.22 created 2024]
 
 


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