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, Sinéad Boyce, Richard Cammack, Ron Caspi, Minoru Kanehisa, 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 entries were added on the date indicated and fully approved after four weeks.

Many thanks to those of you who have submitted details of new or missing enzymes, or updates to existing enzymes.

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


Contents

*EC 1.1.1.193 5-amino-6-(5-phosphoribosylamino)uracil reductase (20 January 2011)
EC 1.1.1.308 sulfopropanediol 3-dehydrogenase (20 January 2011)
EC 1.1.1.309 phosphonoacetaldehyde reductase (NADH) (20 January 2011)
*EC 1.2.1.65 salicylaldehyde dehydrogenase (20 January 2011)
EC 1.2.1.80 long-chain acyl-[acyl-carrier-protein] reductase (20 January 2011)
EC 1.3.1.85 crotonyl-CoA carboxylase/reductase (20 January 2011)
EC 1.3.1.86 crotonyl-CoA reductase (20 January 2011)
EC 1.11.1.19 dye decolorizing peroxidase (20 January 2011)
EC 1.11.2 With H2O2 as acceptor, one oxygen atom of which is incorporated into the product (20 January 2011)
EC 1.11.2.1 unspecific peroxygenase (20 January 2011)
*EC 2.1.1.64 3-demethylubiquinol 3-O-methyltransferase (20 January 2011)
*EC 2.1.1.114 polyprenyldihydroxybenzoate methyltransferase (20 January 2011)
EC 2.4.1.251 GlcA-β-(1→2)-D-Man-α-(1→3)-D-Glc-β-(1→4)-D-Glc-α-1-diphosphoundecaprenol 4-β-mannosyltransferase (20 January 2011)
EC 2.4.1.252 GDP-mannose:cellobiosyl-diphosphopolyprenol α-mannosyltransferase (20 January 2011)
EC 2.4.1.253 baicalein 7-O-glucuronosyltransferase (20 January 2011)
EC 2.5.1.94 adenosyl-chloride synthase (20 January 2011)
EC 2.7.1.169 pantoate kinase (20 January 2011)
*EC 2.7.4.14 UMP/CMP kinase (20 January 2011)
EC 2.7.4.25 (d)CMP kinase (20 January 2011)
EC 2.7.8.31 undecaprenyl-phosphate glucose phosphotransferase (20 January 2011)
EC 3.2.1.167 baicalin-β-D-glucuronidase (20 January 2011)
EC 3.2.1.168 hesperidin 6-O-α-L-rhamnosyl-β-D-glucosidase (20 January 2011)
*EC 3.4.21.6 coagulation factor Xa (20 January 2011)
*EC 3.4.21.60 scutelarin (20 January 2011)
*EC 3.5.1.100 (R)-amidase (20 January 2011)
*EC 3.5.1.102 2-amino-5-formylamino-6-ribosylaminopyrimidin-4(3H)-one 5'-monophosphate deformylase (20 January 2011)
EC 3.5.2.19 streptothricin hydrolase (20 January 2011)
*EC 3.5.4.25 GTP cyclohydrolase II (20 January 2011)
*EC 3.5.4.26 diaminohydroxyphosphoribosylaminopyrimidine deaminase (20 January 2011)
*EC 3.5.4.29 GTP cyclohydrolase IIa (20 January 2011)
EC 3.5.99.8 5-nitroanthranilic acid aminohydrolase (20 January 2011)
*EC 4.1.2.10 (R)-mandelonitrile lyase (20 January 2011)
EC 4.1.2.37 deleted now covered by EC 4.1.2.46 and EC 4.1.2.47 (20 January 2011)
*EC 4.1.2.45 trans-o-hydroxybenzylidenepyruvate hydratase-aldolase (20 January 2011)
EC 4.1.2.46 aliphatic (R)-hydroxynitrile lyase (20 January 2011)
EC 4.1.2.47 (S)-hydroxynitrile lyase (20 January 2011)
*EC 4.1.3.14 L-erythro-3-hydroxyaspartate aldolase (20 January 2011)
EC 4.1.3.41 3-hydroxy-D-aspartate aldolase (20 January 2011)
*EC 4.1.99.5 octadecanal decarbonylase (20 January 2011)
EC 4.2.1.121 colneleate synthase (20 January 2011)
*EC 4.3.1.16 threo-3-hydroxy-L-aspartate ammonia-lyase (20 January 2011)
*EC 4.3.1.20 erythro-3-hydroxy-L-aspartate ammonia-lyase (20 January 2011)
EC 4.3.1.27 threo-3-hydroxy-D-aspartate ammonia-lyase (20 January 2011)
EC 6.3.2.36 4-phosphopantoate—β-alanine ligase (20 January 2011)

*EC 1.1.1.193

Accepted name: 5-amino-6-(5-phosphoribosylamino)uracil reductase

Reaction: 5-amino-6-(5-phospho-D-ribitylamino)uracil + NADP+ = 5-amino-6-(5-phospho-D-ribosylamino)uracil + NADPH + H+

Other name(s): aminodioxyphosphoribosylaminopyrimidine reductase

Systematic name: 5-amino-6-(5-phospho-D-ribitylamino)uracil:NADP+ 1'-oxidoreductase

Links to other databases: BRENDA, EXPASY, KEGG, PDB, CAS registry number: 69020-28-6

References:

1. Burrows, R.B. and Brown, G.M. Presence of Escherichia coli of a deaminase and a reductase involved in biosynthesis of riboflavin. J. Bacteriol. 136 (1978) 657-667. [PMID: 30756]

[EC 1.1.1.193 created 1984, modified 2011]

EC 1.1.1.308

Accepted name: sulfopropanediol 3-dehydrogenase

Reaction: (R)-2,3-dihydroxypropane-1-sulfonate + 2 NAD+ + H2O = (R)-3-sulfolactate + 2 NADH + 2 H+

Other name(s): DHPS 3-dehydrogenase (sulfolactate forming); 2,3-dihydroxypropane-1-sulfonate 3-dehydrogenase (sulfolactate forming); dihydroxypropanesulfonate 3-dehydrogenase; hpsN (gene name)

Systematic name: (R)-2,3-dihydroxypropane-1-sulfonate:NAD+ 3-oxidoreductase

Comments: The enzyme is involved in degradation of (R)-2,3-dihydroxypropanesulfonate.

References:

1. Mayer, J., Huhn, T., Habeck, M., Denger, K., Hollemeyer, K. and Cook, A.M. 2,3-Dihydroxypropane-1-sulfonate degraded by Cupriavidus pinatubonensis JMP134: purification of dihydroxypropanesulfonate 3-dehydrogenase. Microbiology 156 (2010) 1556-1564. [PMID: 20150239]

[EC 1.1.1.308 created 2011]

EC 1.1.1.309

Accepted name: phosphonoacetaldehyde reductase (NADH)

Reaction: 2-hydroxyethylphosphonate + NAD+ = phosphonoacetaldehyde + NADH + H+

Other name(s): PhpC

Systematic name: 2-hydroxyethylphosphonate:NAD+ oxidoreductase

Comments: The enzyme from Streptomyces viridochromogenes catalyses a step in the biosynthesis of phosphinothricin tripeptide, the reduction of phosphonoacetaldehyde to 2-hydroxyethylphosphonate. The preferred cofactor is NADH, lower activity with NADPH [1].

References:

1. Blodgett, J.A., Thomas, P.M., Li, G., Velasquez, J.E., van der Donk, W.A., Kelleher, N.L. and Metcalf, W.W. Unusual transformations in the biosynthesis of the antibiotic phosphinothricin tripeptide. Nat. Chem. Biol. 3 (2007) 480-485. [PMID: 17632514]

[EC 1.1.1.309 created 2011]

*EC 1.2.1.65

Accepted name: salicylaldehyde dehydrogenase

Reaction: salicylaldehyde + NAD+ + H2O = salicylate + NADH + 2 H+

Glossary: salicylaldehyde = 2-hydroxybenzaldehyde

Systematic name: salicylaldehyde:NAD+ oxidoreductase

Comments: Involved in the naphthalene degradation pathway in some bacteria.

Links to other databases: BRENDA, EXPASY, KEGG, UM-BBD, CAS registry number: 55354-34-2

References:

1. Eaton, R. and Chapman, P.J. Bacterial metabolism of naphthalene: construction and use of recombinant bacteria to study ring cleavage of 1,2-dihydroxynaphthalene and subsequent reactions. J. Bacteriol. 174 (1992) 7542-7554. [PMID: 1447127]

[EC 1.2.1.65 created 2000, modified 2011]

EC 1.2.1.80

Accepted name: long-chain acyl-[acyl-carrier-protein] reductase

Reaction: a long-chain aldehyde + acyl-carrier protein + NAD(P)+ = a long-chain acyl-[acyl-carrier protein] + NAD(P)H + H+

Glossary: a long-chain aldehyde = a fatty aldehyde
acyl-carrier protein = ACP = [acp]

Other name(s): long-chain acyl-[acp] reductase; fatty acyl-[acyl-carrier-protein] reductase; acyl-[acp] reductase

Systematic name: long-chain-aldehyde:NAD(P)+ oxidoreductase (acyl-[acyl-carrier protein]-forming)

Comments: Catalyses the reaction in the opposite direction. This enzyme, purified from the cyanobacterium Synechococcus elongatus PCC 7942, catalyses the NAD(P)HĐdependent reduction of an activated fatty acid (acyl-[acp]) to the corresponding aldehyde. Together with EC 4.1.99.5, octadecanal decarbonylase, it is involved in alkane biosynthesis. The natural substrates of the enzyme are C16 to C18 activated fatty acids. Requires Mg2+.

References:

1. Schirmer, A., Rude, M.A., Li, X., Popova, E. and del Cardayre, S.B. Microbial biosynthesis of alkanes. Science 329 (2010) 559-562. [PMID: 20671186]

[EC 1.2.1.80 created 2011]

EC 1.3.1.85

Accepted name: crotonyl-CoA carboxylase/reductase

Reaction: (2S)-ethylmalonyl-CoA + NADP+ = (E)-but-2-enoyl-CoA + CO2 + NADPH + H+

Glossary: (E)-but-2-enoyl-CoA = crotonyl-CoA

Other name(s): CCR; crotonyl-CoA reductase (carboxylating)

Systematic name: (2S)-ethylmalonyl-CoA:NADP+ oxidoreductase (decarboxylating)

Comments: The reaction is catalysed in the reverse direction. This enzyme, isolated from the bacterium Rhodobacter sphaeroides, catalyses (E)-but-2-enoyl-CoA-dependent oxidation of NADPH in the presence of CO2. When CO2 is absent, the enzyme catalyses the reduction of (E)-but-2-enoyl-CoA to butanoyl-CoA, but with only 10% of maximal activity (relative to (E)-but-2-enoyl-CoA carboxylation).

References:

1. Erb, T.J., Berg, I.A., Brecht, V., Muller, M., Fuchs, G. and Alber, B.E. Synthesis of C5-dicarboxylic acids from C2-units involving crotonyl-CoA carboxylase/reductase: the ethylmalonyl-CoA pathway. Proc. Natl. Acad. Sci. USA 104 (2007) 10631-10636. [PMID: 17548827]

2. Erb, T.J., Brecht, V., Fuchs, G., Muller, M. and Alber, B.E. Carboxylation mechanism and stereochemistry of crotonyl-CoA carboxylase/reductase, a carboxylating enoyl-thioester reductase. Proc. Natl. Acad. Sci. USA 106 (2009) 8871-8876. [PMID: 19458256]

[EC 1.3.1.85 created 2011]

EC 1.3.1.86

Accepted name: crotonyl-CoA reductase

Reaction: butanoyl-CoA + NADP+ = (E)-but-2-enoyl-CoA + NADPH + H+

Glossary: (E)-but-2-enoyl-CoA = crotonyl-CoA, butanoyl-CoA = butyryl-CoA

Other name(s): butyryl-CoA dehydrogenase; butyryl dehydrogenase; unsaturated acyl-CoA reductase; ethylene reductase; enoyl-coenzyme A reductase; unsaturated acyl coenzyme A reductase; butyryl coenzyme A dehydrogenase; short-chain acyl CoA dehydrogenase; short-chain acyl-coenzyme A dehydrogenase; 3-hydroxyacyl CoA reductase; butanoyl-CoA:(acceptor) 2,3-oxidoreductase; CCR

Systematic name: butanoyl-CoA:NADP+ 2,3-oxidoreductase

Comments: Catalyses the reaction in the reverse direction. This enzyme from Streptomyces collinus is specific for (E)-but-2-enoyl-CoA, and is proposed to provide butanoyl-CoA as a starter unit for straight-chain fatty acid biosynthesis.

References:

1. Wallace, K.K., Bao, Z.Y., Dai, H., Digate, R., Schuler, G., Speedie, M.K. and Reynolds, K.A. Purification of crotonyl-CoA reductase from Streptomyces collinus and cloning, sequencing and expression of the corresponding gene in Escherichia coli. Eur. J. Biochem. 233 (1995) 954-962. [PMID: 8521864]

[EC 1.3.1.86 created 2011]

EC 1.11.1.19

Accepted name: dye decolorizing peroxidase

Reaction: Reactive Blue 5 + H2O2 + 2 H+ = oxidized Reactive Blue 5 + 2 H2O

Glossary: Reactive Blue 5 = 1-Amino-4-{[3-({4-chloro-6-[(3-sulfophenyl)amino]-1,3,5-triazin-2-yl}amino)-4-sulfophenyl]amino}-9,10-dihydro-9,10-dioxoanthracene-2-sulfonic acid

Other name(s): DyP; DyP-type peroxidase

Systematic name: Reactive-Blue-5:hydrogen-peroxide oxidoreductase

Comments: Heme proteins with proximal histidine secreted by basidiomycetous fungi and eubacteria. They are similar to EC 1.11.1.16 versatile peroxidase (oxidation of Reactive Black 5, phenols, veratryl alcohol), but differ from the latter in their ability to efficiently oxidize a number of recalcitrant anthraquinone dyes, and inability to oxidize Mn(II). The model substrate Reactive Blue 5 is converted with high efficiency via a so far unique mechanism that combines oxidative and hydrolytic steps and leads to the formation of phthalic acid. Bacterial TfuDyP catalyses sulfoxidation.

References:

1. Kim, S.J. and Shoda, M. Purification and characterization of a novel peroxidase from Geotrichum candidum dec 1 involved in decolorization of dyes. Appl. Environ. Microbiol. 65 (1999) 1029-1035. [PMID: 10049859]

2. Sugano, Y., Ishii, Y. and Shoda, M. Role of H164 in a unique dye-decolorizing heme peroxidase DyP. Biochem. Biophys. Res. Commun. 322 (2004) 126-132. [PMID: 15313183]

3. Zubieta, C., Joseph, R., Krishna, S.S., McMullan, D., Kapoor, M., Axelrod, H.L., Miller, M.D., Abdubek, P., Acosta, C., Astakhova, T., Carlton, D., Chiu, H.J., Clayton, T., Deller, M.C., Duan, L., Elias, Y., Elsliger, M.A., Feuerhelm, J., Grzechnik, S.K., Hale, J., Han, G.W., Jaroszewski, L., Jin, K.K., Klock, H.E., Knuth, M.W., Kozbial, P., Kumar, A., Marciano, D., Morse, A.T., Murphy, K.D., Nigoghossian, E., Okach, L., Oommachen, S., Reyes, R., Rife, C.L., Schimmel, P., Trout, C.V., van den Bedem, H., Weekes, D., White, A., Xu, Q., Hodgson, K.O., Wooley, J., Deacon, A.M., Godzik, A., Lesley, S.A. and Wilson, I.A. Identification and structural characterization of heme binding in a novel dye-decolorizing peroxidase, TyrA. Proteins 69 (2007) 234-243. [PMID: 17654547]

4. Sugano, Y., Matsushima, Y., Tsuchiya, K., Aoki, H., Hirai, M. and Shoda, M. Degradation pathway of an anthraquinone dye catalyzed by a unique peroxidase DyP from Thanatephorus cucumeris Dec 1. Biodegradation 20 (2009) 433-440. [PMID: 19009358]

5. Sugano, Y. DyP-type peroxidases comprise a novel heme peroxidase family. Cell. Mol. Life Sci. 66 (2009) 1387-1403. [PMID: 19099183]

6. Ogola, H.J., Kamiike, T., Hashimoto, N., Ashida, H., Ishikawa, T., Shibata, H. and Sawa, Y. Molecular characterization of a novel peroxidase from the cyanobacterium Anabaena sp. strain PCC 7120. Appl. Environ. Microbiol. 75 (2009) 7509-7518. [PMID: 19801472]

7. van Bloois, E., Torres Pazmino, D.E., Winter, R.T. and Fraaije, M.W. A robust and extracellular heme-containing peroxidase from Thermobifida fusca as prototype of a bacterial peroxidase superfamily. Appl. Microbiol. Biotechnol. 86 (2010) 1419-1430. [PMID: 19967355]

8. Liers, C., Bobeth, C., Pecyna, M., Ullrich, R. and Hofrichter, M. DyP-like peroxidases of the jelly fungus Auricularia auricula-judae oxidize nonphenolic lignin model compounds and high-redox potential dyes. Appl. Microbiol. Biotechnol. 85 (2010) 1869-1879. [PMID: 19756587]

9. Hofrichter, M., Ullrich, R., Pecyna, M.J., Liers, C. and Lundell, T. New and classic families of secreted fungal heme peroxidases. Appl. Microbiol. Biotechnol. 87 (2010) 871-897. [PMID: 20495915]

[EC 1.11.1.19 created 2011]

EC 1.11.2 With H2O2 as acceptor, one oxygen atom of which is incorporated into the product
EC 1.11.2.1

Accepted name: unspecific peroxygenase

Reaction: RH + H2O2 = ROH + H2O

Other name(s): aromatic peroxygenase; mushroom peroxygenase; haloperoxidase-peroxygenase; Agrocybe aegerita peroxidase

Systematic name: substrate:hydrogen peroxide oxidoreductase (RH-hydroxylating or -epoxidising)

Comments: A heme-thiolate protein (P450). Enzymes of this type include glycoproteins secreted by agaric basidiomycetes. They catalyse the insertion of an oxygen atom from H2O2 into a wide variety of substrates, including aromatic rings such as naphthalene, toluene, phenanthrene, pyrene and p-nitrophenol, recalcitrant heterocycles such as pyridine, dibenzofuran, various ethers (resulting in O-dealkylation) and alkanes such as propane, hexane and cyclohexane. Reactions catalysed include hydroxylation, epoxidation, N-oxidation, sulfooxidation, O- and N-dealkylation, bromination and one-electron oxidations. They have little or no activity toward chloride. Mechanistically, the catalytic cycle of unspecific (mono)-peroxygenases combines elements of the "shunt" pathway of cytochrome P450s (a side activity that utilizes a peroxide in place of dioxygen and NAD[P]H) and the classic heme peroxidase cycle.

References:

1. Ullrich, R., Nuske, J., Scheibner, K., Spantzel, J. and Hofrichter, M. Novel haloperoxidase from the agaric basidiomycete Agrocybe aegerita oxidizes aryl alcohols and aldehydes. Appl. Environ. Microbiol. 70 (2004) 4575-4581. [PMID: 15294788]

2. Ullrich, R. and Hofrichter, M. The haloperoxidase of the agaric fungus Agrocybe aegerita hydroxylates toluene and naphthalene. FEBS Lett. 579 (2005) 6247-6250. [PMID: 16253244]

3. Anh, D.H., Ullrich, R., Benndorf, D., Svatos, A., Muck, A. and Hofrichter, M. The coprophilous mushroom Coprinus radians secretes a haloperoxidase that catalyzes aromatic peroxygenation. Appl. Environ. Microbiol. 73 (2007) 5477-5485. [PMID: 17601809]

4. Aranda, E., Kinne, M., Kluge, M., Ullrich, R. and Hofrichter, M. Conversion of dibenzothiophene by the mushrooms Agrocybe aegerita and Coprinellus radians and their extracellular peroxygenases. Appl. Microbiol. Biotechnol. 82 (2009) 1057-1066. [PMID: 19039585]

5. Kinne, M., Poraj-Kobielska, M., Aranda, E., Ullrich, R., Hammel, K.E., Scheibner, K. and Hofrichter, M. Regioselective preparation of 5-hydroxypropranolol and 4'-hydroxydiclofenac with a fungal peroxygenase. Bioorg. Med. Chem. Lett. 19 (2009) 3085-3087. [PMID: 19394224]

6. Kluge, M., Ullrich, R., Dolge, C., Scheibner, K. and Hofrichter, M. Hydroxylation of naphthalene by aromatic peroxygenase from Agrocybe aegerita proceeds via oxygen transfer from H2O2 and intermediary epoxidation. Appl. Microbiol. Biotechnol. 81 (2009) 1071-1076. [PMID: 18815784]

7. Ullrich, R., Dolge, C., Kluge, M. and Hofrichter, M. Pyridine as novel substrate for regioselective oxygenation with aromatic peroxygenase from Agrocybe aegerita. FEBS Lett. 582 (2008) 4100-4106. [PMID: 19022254]

8. Aranda, E., Kinne, M., Kluge, M., Ullrich, R. and Hofrichter, M. Conversion of dibenzothiophene by the mushrooms Agrocybe aegerita and Coprinellus radians and their extracellular peroxygenases. Appl. Microbiol. Biotechnol. 82 (2009) 1057-1066. [PMID: 19039585]

9. Kinne, M., Poraj-Kobielska, M., Ralph, S.A., Ullrich, R., Hofrichter, M. and Hammel, K.E. Oxidative cleavage of diverse ethers by an extracellular fungal peroxygenase. J. Biol. Chem. 284 (2009) 29343-29349. [PMID: 19713216]

10. Pecyna, M.J., Ullrich, R., Bittner, B., Clemens, A., Scheibner, K., Schubert, R. and Hofrichter, M. Molecular characterization of aromatic peroxygenase from Agrocybe aegerita. Appl. Microbiol. Biotechnol. 84 (2009) 885-897. [PMID: 19434406]

[EC 1.11.2.1 created 2011]

*EC 2.1.1.64

Accepted name: 3-demethylubiquinol 3-O-methyltransferase

Reaction: S-adenosyl-L-methionine + 3-demethylubiquinol-n = S-adenosyl-L-homocysteine + ubiquinol-n

Glossary: 3-demethylubiquinol-n = 3-hydroxy-2-methoxy-5-methyl-6-(all-trans-polyprenyl)-1,4-benzoquinol

Other name(s): 5-demethylubiquinone-9 methyltransferase; OMHMB-methyltransferase; 2-octaprenyl-3-methyl-5-hydroxy-6-methoxy-1,4-benzoquinone methyltransferase; S-adenosyl-L-methionine:2-octaprenyl-3-methyl-5-hydroxy-6-methoxy-1,4-benzoquinone-O-methyltransferase; COQ3 (gene name); Coq3 O-methyltransferase; ubiG (gene name, ambiguous)

Systematic name: S-adenosyl-L-methionine:3-hydroxy-2-methoxy-5-methyl-6-(all-trans-polyprenyl)-1,4-benzoquinol 3-O-methyltransferase

Comments: This enzyme is involved in ubiquinone biosynthesis. Ubiquinones from different organisms have a different number of prenyl units (for example, ubiquinone-6 in Saccharomyces, ubiquinone-9 in rat and ubiquinone-10 in human), and thus the natural substrate for the enzymes from different organisms has a different number of prenyl units. However, the enzyme usually shows a low degree of specificity regarding the number of prenyl units. For example, the human COQ3 enzyme can restore biosynthesis of ubiquinone-6 in coq3 deletion mutants of yeast [3]. The enzymes from yeast, Escherichia coli and rat also catalyse the methylation of 3,4-dihydroxy-5-all-trans-polyprenylbenzoate [3] (a reaction that is classified as EC 2.1.1.114, polyprenyldihydroxybenzoate methyltransferase).

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 63774-48-1

References:

1. Houser, R.M. and Olson, R.E. 5-Demethylubiquinone-9-methyltransferase from rat liver mitochondria. Characterization, localization, and solubilization. J. Biol. Chem. 252 (1977) 4017-4021. [PMID: 863914]

2. Leppik, R.A., Stroobant, P., Shineberg, B., Young, I.G. and Gibson, F. Membrane-associated reactions in ubiquinone biosynthesis. 2-Octaprenyl-3-methyl-5-hydroxy-6-methoxy-1,4-benzoquinone methyltransferase. Biochim. Biophys. Acta 428 (1976) 146-156. [PMID: 769831]

3. Poon, W.W., Barkovich, R.J., Hsu, A.Y., Frankel, A., Lee, P.T., Shepherd, J.N., Myles, D.C. and Clarke, C.F. Yeast and rat Coq3 and Escherichia coli UbiG polypeptides catalyze both O-methyltransferase steps in coenzyme Q biosynthesis. J. Biol. Chem. 274 (1999) 21665-21672. [PMID: 10419476]

4. Jonassen, T. and Clarke, C.F. Isolation and functional expression of human COQ3, a gene encoding a methyltransferase required for ubiquinone biosynthesis. J. Biol. Chem. 275 (2000) 12381-12387. [PMID: 10777520]

[EC 2.1.1.64 created 1982, modified 2011]

*EC 2.1.1.114

Accepted name: polyprenyldihydroxybenzoate methyltransferase

Reaction: S-adenosyl-L-methionine + 3,4-dihydroxy-5-all-trans-polyprenylbenzoate = S-adenosyl-L-homocysteine + 3-methoxy-4-hydroxy-5-all-trans-polyprenylbenzoate

Other name(s): 3,4-dihydroxy-5-hexaprenylbenzoate methyltransferase; dihydroxyhexaprenylbenzoate methyltransferase; COQ3 (gene name); Coq3 O-methyltransferase

Systematic name: S-adenosyl-L-methionine:3,4-dihydroxy-5-all-trans-polyprenylbenzoate 3-O-methyltransferase

Comments: This enzyme is involved in ubiquinone biosynthesis. Ubiquinones from different organisms have a different number of prenyl units (for example, ubiquinone-6 in Saccharomyces, ubiquinone-9 in rat and ubiquinone-10 in human), and thus the natural substrate for the enzymes from different organisms has a different number of prenyl units. However, the enzyme usually shows a low degree of specificity regarding the number of prenyl units. For example, the human COQ3 enzyme can restore biosynthesis of ubiquinone-6 in coq3 deletion mutants of yeast [3]. The enzymes from yeast and rat also catalyse the methylation of 3-demethylubiquinol-6 and 3-demethylubiquinol-9, respectively [2] (this activity is classified as EC 2.1.1.64, 3-demethylubiquinol 3-O-methyltransferase).

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 139569-31-6

References:

1. Clarke, C.F., Williams, W., Teruya, J.H. Ubiquinone biosynthesis in Saccharomyces cerevisiae. Isolation and sequence of COQ3, the 3,4-dihydroxy-5-hexaprenylbenzoate methyltransferase gene. J. Biol. Chem. 266 (1991) 16636-16641. [PMID: 1885593]

2. Poon, W.W., Barkovich, R.J., Hsu, A.Y., Frankel, A., Lee, P.T., Shepherd, J.N., Myles, D.C. and Clarke, C.F. Yeast and rat Coq3 and Escherichia coli UbiG polypeptides catalyze both O-methyltransferase steps in coenzyme Q biosynthesis. J. Biol. Chem. 274 (1999) 21665-21672. [PMID: 10419476]

3. Jonassen, T. and Clarke, C.F. Isolation and functional expression of human COQ3, a gene encoding a methyltransferase required for ubiquinone biosynthesis. J. Biol. Chem. 275 (2000) 12381-12387. [PMID: 10777520]

[EC 2.1.1.114 created 1999, modified 2011]

EC 2.4.1.251

Accepted name: GlcA-β-(1→2)-D-Man-α-(1→3)-D-Glc-β-(1→4)-D-Glc-α-1-diphosphoundecaprenol 4-β-mannosyltransferase

Reaction: GDP-mannose + GlcA-β-(1→2)-D-Man-α-(1→3)-D-Glc-β-(1→4)-D-Glc-α-1-diphospho-ditrans,octacis-undecaprenol = GDP + D-Man-β-(1→4)- GlcA-β-(1→2)-D-Man-α-(1→3)-D-Glc-β-(1→4)-D-Glc-α-1-diphospho-ditrans,octacis-undecaprenol

Other name(s): GumI

Systematic name: GDP-mannose:GlcA-β-(1→2)-D-Man-α-(1→3)-D-Glc-β-(1→4)-D-Glc-α-1-diphospho-ditrans,octacis-undecaprenol 4-β-mannosyltransferase

Comments: The enzyme is involved in the biosynthesis of the exopolysaccharide xanthan.

References:

1. Katzen, F., Ferreiro, D.U., Oddo, C.G., Ielmini, M.V., Becker, A., Puhler, A. and Ielpi, L. Xanthomonas campestris pv. campestris gum mutants: effects on xanthan biosynthesis and plant virulence. J. Bacteriol. 180 (1998) 1607-1617. [PMID: 9537354]

2. Ielpi, L., Couso, R.O. and Dankert, M.A. Sequential assembly and polymerization of the polyprenol-linked pentasaccharide repeating unit of the xanthan polysaccharide in Xanthomonas campestris. J. Bacteriol. 175 (1993) 2490-2500. [PMID: 7683019]

3. Kim, S.Y., Kim, J.G., Lee, B.M. and Cho, J.Y. Mutational analysis of the gum gene cluster required for xanthan biosynthesis in Xanthomonas oryzae pv oryzae. Biotechnol. Lett. 31 (2009) 265-270. [PMID: 18854951]

[EC 2.4.1.251 created 2011]

EC 2.4.1.252

Accepted name: GDP-mannose:cellobiosyl-diphosphopolyprenol α-mannosyltransferase

Reaction: GDP-mannose + D-Glc-β-(1→4)-Glc-α-1-diphospho-ditrans,octacis-undecaprenol = GDP + D-Man-α-(1→3)-D-Glc-β-(1→4)-D-Glc-α-1-diphospho-ditrans,octacis-undecaprenol

Other name(s): GumH; AceA; α1,3-mannosyltransferase AceA

Systematic name: GDP-mannose:D-Glc-β-(1→4)-Glc-α-1-diphospho-ditrans,octacis-undecaprenol 3-α-mannosyltransferase

Comments: In the bacterium Gluconacetobacter xylinus (previously known as Acetobacter xylinum) the enzyme is involved in the biosynthesis of the exopolysaccharide acetan [1]. In Xanthomonas campestris the enzyme is involved in the biosynthesis of the exopolysaccharide xanthan [5].

References:

1. Geremia, R.A., Roux, M., Ferreiro, D.U., Dauphin-Dubois, R., Lellouch, A.C. and Ielpi, L. Expression and biochemical characterisation of recombinant AceA, a bacterial α-mannosyltransferase. Mol. Gen. Genet. 261 (1999) 933-940. [PMID: 10485283]

2. Abdian, P.L., Lellouch, A.C., Gautier, C., Ielpi, L. and Geremia, R.A. Identification of essential amino acids in the bacterial α-mannosyltransferase aceA. J. Biol. Chem. 275 (2000) 40568-40575. [PMID: 11001941]

3. Petroni, E.A. and Ielpi, L. Isolation and nucleotide sequence of the GDP-mannose:cellobiosyl-diphosphopolyprenol α-mannosyltransferase gene from Acetobacter xylinum. J. Bacteriol. 178 (1996) 4814-4821. [PMID: 8759843]

4. Lellouch, A.C., Watt, G.M., Geremia, R.A. and Flitsch, S.L. Phytanyl-pyrophosphate-linked substrate for a bacterial α-mannosyltransferase. Biochem. Biophys. Res. Commun. 272 (2000) 290-292. [PMID: 10872841]

5. Katzen, F., Ferreiro, D.U., Oddo, C.G., Ielmini, M.V., Becker, A., Puhler, A. and Ielpi, L. Xanthomonas campestris pv. campestris gum mutants: effects on xanthan biosynthesis and plant virulence. J. Bacteriol. 180 (1998) 1607-1617. [PMID: 9537354]

[EC 2.4.1.252 created 2011]

EC 2.4.1.253

Accepted name: baicalein 7-O-glucuronosyltransferase

Reaction: UDP-D-glucuronate + baicalein = UDP + baicalin

Glossary: baicalin = 5,6,7-trihydroxyflavone-7-O-β-D-glucuronate = 5,6-dihydroxy-4-oxo-2-phenyl-4H-chromen-7-yl β-D-glucupyranosiduronic acid
baicalein = 5,6,7-trihydroxyflavone = 5,6,7-trihydroxy-2-phenyl-4H-chromen-4-one
wogonin = 5,7-dihydroxy-8-methoxyflavone = 5,7-dihydroxy-8-methoxy-2-phenyl-4H-chromen-4-one
scutellarein = 4,5,6,7-tetrahydroxyflavone-7-O-β-D-glucoronate = 5,6,7-trihydroxy-2-(4-hydroxyphenyl)chromen-4-one

Other name(s): UBGAT

Systematic name: UDP-D-glucuronate:5,6,7-trihydroxyflavone 7-O-glucuronosyltransferase

Comments: The enzyme is specific for UDP-D-glucuronate as a sugar donor and flavones with substitution ortho- to the 7-OH group such as baicalein (6-OH), scutellarein (6-OH) and wogonin (8-OMe).

References:

1. Nagashima, S., Hirotani, M. and Yoshikawa, T. Purification and characterization of UDP-glucuronate: baicalein 7-O-glucuronosyltransferase from Scutellaria baicalensis Georgi. cell suspension cultures. Phytochemistry 53 (2000) 533-538. [PMID: 10724177]

[EC 2.4.1.253 created 2011]

EC 2.5.1.94

Accepted name: adenosyl-chloride synthase

Reaction: S-adenosyl-L-methionine + chloride = 5-deoxy-5-chloroadenosine + L-methionine

Glossary: 5-deoxy-5-chloroadenosine = 5'-chloro-5'-deoxyadenosine

Other name(s): chlorinase; 5'-chloro-5'-deoxyadenosine synthase

Systematic name: S-adenosyl-L-methionine:chloride adenosyltransferase

Comments: This enzyme, isolated from the marine bacterium Salinispora tropica, catalyses an early step in the pathway leading to biosynthesis of the proteosome inhibitor salinosporamide A. The enzyme is very similar to EC 2.5.1.63, adenosyl-fluoride synthase, but does not accept fluoride.

References:

1. Eustaquio, A.S., Pojer, F., Noel, J.P. and Moore, B.S. Discovery and characterization of a marine bacterial SAM-dependent chlorinase. Nat. Chem. Biol. 4 (2008) 69-74. [PMID: 18059261]

[EC 2.5.1.94 created 2011]

EC 2.7.1.169

Accepted name: pantoate kinase

Reaction: ATP + (R)-pantoate = ADP + (R)-4-phosphopantoate

Other name(s): PoK; TK2141 protein

Systematic name: ATP:(R)-pantoate 4-phosphotransferase

Comments: The conversion of (R)-pantoate to (R)-4'-phosphopantothenate is part of the pathway leading to biosynthesis of 4'-phosphopantetheine, an essential cofactor of coenzyme A and acyl-carrier protein. In bacteria and eukaryotes this conversion is performed by condensation with β-alanine, followed by phosphorylation (EC 6.3.2.1 and EC 2.7.1.33, respectively). In archaea the order of these two steps is reversed, and phosphorylation precedes condensation with β-alanine.

References:

1. Yokooji, Y., Tomita, H., Atomi, H. and Imanaka, T. Pantoate kinase and phosphopantothenate synthetase, two novel enzymes necessary for CoA biosynthesis in the Archaea. J. Biol. Chem. 284 (2009) 28137-28145. [PMID: 19666462]

[EC 2.7.1.169 created 2011]

*EC 2.7.4.14

Accepted name: UMP/CMP kinase

Reaction: (1) ATP + (d)CMP = ADP + (d)CDP
(2) ATP + UMP = ADP + UDP

Glossary: CMP = cytidine monophosphate
dCMP = deoxycytidine monophosphate
CDP = cytidine diphosphate
dCDP = deoxycytidine diphosphate
UMP = uridine monophosphate
UDP = uridine diphosphate

Other name(s): cytidylate kinase; deoxycytidylate kinase; CTP:CMP phosphotransferase; dCMP kinase; deoxycytidine monophosphokinase; UMP-CMP kinase; ATP:UMP-CMP phosphotransferase; pyrimidine nucleoside monophosphate kinase; uridine monophosphate-cytidine monophosphate phosphotransferase

Systematic name: ATP:CMP(UMP) phosphotransferase

Comments: This eukaryotic enzyme is a bifunctional enzyme that catalyses the phosphorylation of both CMP and UMP with similar efficiency. dCMP can also act as acceptor. Different from the monofunctional prokaryotic enzymes EC 2.7.4.25, CMP kinase and EC 2.7.4.22, UMP kinase.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, PDB, CAS registry number: 37278-21-0

References:

1. Hurwitz, J. The enzymatic incorporation of ribonucleotides into polydeoxynucleotide material. J. Biol. Chem. 234 (1959) 2351-2358. [PMID: 14405566]

2. Ruffner, B.W., Jr. and Anderson, E.P. Adenosine triphosphate: uridine monophosphate-cytidine monophosphate phosphotransferase from Tetrahymena pyriformis. J. Biol. Chem. 244 (1969) 5994-6002. [PMID: 5350952]

3. Scheffzek, K., Kliche, W., Wiesmuller, L. and Reinstein, J. Crystal structure of the complex of UMP/CMP kinase from Dictyostelium discoideum and the bisubstrate inhibitor P1-(5'-adenosyl) P5-(5'-uridyl) pentaphosphate (UP5A) and Mg2+ at 2.2 Å: implications for water-mediated specificity. Biochemistry 35 (1996) 9716-9727. [PMID: 8703943]

4. Zhou, L., Lacroute, F. and Thornburg, R. Cloning, expression in Escherichia coli, and characterization of Arabidopsis thaliana UMP/CMP kinase. Plant Physiol. 117 (1998) 245-254. [PMID: 9576794]

5. Van Rompay, A.R., Johansson, M. and Karlsson, A. Phosphorylation of deoxycytidine analog monophosphates by UMP-CMP kinase: molecular characterization of the human enzyme. Mol. Pharmacol. 56 (1999) 562-569. [PMID: 10462544]

[EC 2.7.4.14 created 1961 as EC 2.7.4.5, transferred 1972 to EC 2.7.4.14, modified 1980, modified 2011]

EC 2.7.4.25

Accepted name: (d)CMP kinase

Reaction: ATP + (d)CMP = ADP + (d)CDP

Glossary: CMP = cytidine monophosphate
dCMP = deoxycytidine monophosphate
CDP = cytidine diphosphate
dCDP = deoxycytidine diphosphate
UMP = uridine monophosphate
UDP = uridine diphosphate

Other name(s): prokaryotic cytidylate kinase; deoxycytidylate kinase; dCMP kinase; deoxycytidine monophosphokinase

Systematic name: ATP:(d)CMP phosphotransferase

Comments: The prokaryotic cytidine monophosphate kinase specifically phosphorylates CMP (or dCMP), using ATP as the preferred phosphoryl donor. Unlike EC 2.7.4.14, a eukaryotic enzyme that phosphorylates UMP and CMP with similar efficiency, the prokaryotic enzyme phosphorylates UMP with very low rates, and this function is catalysed in prokaryotes by EC 2.7.4.22, UMP kinase. The enzyme phosphorylates dCMP nearly as well as it does CMP [1].

References:

1. Bertrand, T., Briozzo, P., Assairi, L., Ofiteru, A., Bucurenci, N., Munier-Lehmann, H., Golinelli-Pimpaneau, B., Barzu, O. and Gilles, A.M. Sugar specificity of bacterial CMP kinases as revealed by crystal structures and mutagenesis of Escherichia coli enzyme. J. Mol. Biol. 315 (2002) 1099-1110. [PMID: 11827479]

2. Thum, C., Schneider, C.Z., Palma, M.S., Santos, D.S. and Basso, L.A. The Rv1712 Locus from Mycobacterium tuberculosis H37Rv codes for a functional CMP kinase that preferentially phosphorylates dCMP. J. Bacteriol. 191 (2009) 2884-2887. [PMID: 19181797]

[EC 2.7.4.25 created 2011]

EC 2.7.8.31

Accepted name: undecaprenyl-phosphate glucose phosphotransferase

Reaction: UDP-glucose + ditrans,octacis-undecaprenyl phosphate = UMP + α-D-glucopyranosyl-diphospho-ditrans,octacis-undecaprenol

Other name(s): GumD; undecaprenylphosphate glucosylphosphate transferase

Systematic name: UDP-glucose:-ditrans,octacis-undecaprenyl-phosphate glucose phosphotransferase

Comments: The enzyme is involved in biosynthesis of xanthan.

References:

1. Ielpi, L., Couso, R.O. and Dankert, M.A. Sequential assembly and polymerization of the polyprenol-linked pentasaccharide repeating unit of the xanthan polysaccharide in Xanthomonas campestris. J. Bacteriol. 175 (1993) 2490-2500. [PMID: 7683019]

2. Katzen, F., Ferreiro, D.U., Oddo, C.G., Ielmini, M.V., Becker, A., Puhler, A. and Ielpi, L. Xanthomonas campestris pv. campestris gum mutants: effects on xanthan biosynthesis and plant virulence. J. Bacteriol. 180 (1998) 1607-1617. [PMID: 9537354]

3. Kim, S.Y., Kim, J.G., Lee, B.M. and Cho, J.Y. Mutational analysis of the gum gene cluster required for xanthan biosynthesis in Xanthomonas oryzae pv oryzae. Biotechnol. Lett. 31 (2009) 265-270. [PMID: 18854951]

[EC 2.7.8.31 created 2011]

EC 3.2.1.167

Accepted name: baicalin-β-D-glucuronidase

Reaction: baicalin + H2O = baicalein + D-glucuronate

Glossary: baicalin = 5,6,7-trihydroxyflavone-7-O-β-D-glucuronate = 5,6-dihydroxy-4-oxo-2-phenyl-4H-chromen-7-yl β-D-glucupyranosiduronic acid
baicalein = 5,6,7-trihydroxyflavone = 5,6,7-trihydroxy-2-phenyl-4H-chromen-4-one
wogonin = 5,7-dihydroxy-8-methoxyflavone = 5,7-dihydroxy-8-methoxy-2-phenyl-4H-chromen-4-one
oroxylin = 5,7-dihydroxy-6-methoxyflavone = 5,7-dihydroxy-6-methoxy-2-phenyl-4H-1-benzopyran-4-one

Other name(s): baicalinase

Systematic name: 5,6,7-trihydroxyflavone-7-O-β-D-glucupyranosiduronate glucuronosylhydrolase

Comments: The enzyme also hydrolyses wogonin 7-O-β-D-glucuronide and oroxylin 7-O-β-D-glucuronide with lower efficiency [4]. Neglegible activity with p-nitrophenyl-β-D-glucuronide [2].

References:

1. Ikegami, F., Matsunae, K., Hisamitsu, M., Kurihara, T., Yamamoto, T. and Murakoshi, I. Purification and properties of a plant β-D-glucuronidase form Scutellaria root. Biol. Pharm. Bull. 18 (1995) 1531-1534. [PMID: 8593473]

2. Zhang, C., Zhang, Y., Chen, J. and Liang, X. Purification and characterization of baicalin-β-D-glucuronidase hydrolyzing baicalin to baicalein from fresh roots of Scutellaria viscidula Bge. Proc. Biochem. 40 (2005) 1911-1915.

3. Sasaki, K., Taura, F., Shoyama, Y. and Morimoto, S. Molecular characterization of a novel β-glucuronidase from Scutellaria baicalensis Georgi. J. Biol. Chem. 275 (2000) 27466-27472. [PMID: 10858442]

4. Morimoto, S., Harioka, T. and Shoyama, Y. Purification and characterization of flavone-specific β-glucuronidase from callus cultures of Scutellaria baicalensis Georgi. Planta 195 (1995) 535-540.

[EC 3.2.1.167 created 2011]

EC 3.2.1.168

Accepted name: hesperidin 6-O-α-L-rhamnosyl-β-D-glucosidase

Reaction: hesperidin + H2O = hesperitin + rutinose

Glossary: hesperitin = 5,7,3'-trihydroxy-4'-methoxyflavanone
hesperidin = hesperitin 7-(6-O-α-L-rhamnopyranosyl)-β-D-glucopyranoside
rutinose = 6-O-α-L-rhamnopyranosyl-D-glucose

Systematic name: hesperetin 7-(6-O-α-L-rhamnopyranosyl-β-D-glucopyranoside) 6-O-α-rhamnopyranosyl-β-glucohydrolase

Comments: The enzyme exhibits high specificity towards 7-O-linked flavonoid β-rutinosides.

References:

1. Mazzaferro, L., Pinuel, L., Minig, M. and Breccia, J.D. Extracellular monoenzyme deglycosylation system of 7-O-linked flavonoid β-rutinosides and its disaccharide transglycosylation activity from Stilbella fimetaria. Arch. Microbiol. 192 (2010) 383-393. [PMID: 20358178]

[EC 3.2.1.168 created 2011]

*EC 3.4.21.6

Accepted name: coagulation factor Xa

Reaction: Selective cleavage of ArgThr and then ArgIle bonds in prothrombin to form thrombin

Other name(s): thrombokinase; prothrombase; prothrombinase; activated blood-coagulation factor X; autoprothrombin C; thromboplastin; plasma thromboplastin; factor Xa; activated Stuart-Prower factor; activated factor X

Comments: A blood coagulation factor formed from the proenzyme factor X by limited proteolysis. Factor X is a glycoprotein composed of a heavy chain and a light chain, which are generated from a precursor protein by the excision of the tripeptide RKR and held together by one or more disulfide bonds. The activated factor Xa converts prothrombin to thrombin in the presence of factor Va, Ca2+ and phospholipids. Scutelarin (EC 3.4.21.60) has similar specificity, but does not require factor Va.

Links to other databases: BRENDA, KEGG, MEROPS, PDB, CAS registry number: 9002-05-5

References:

1. Fujikawa, K. and Davie, E.W. Bovine factor X (Stuart factor). Methods Enzymol. 45 (1976) 89-95. [PMID: 1012041]

2. Jesty, J. and Nemerson, Y. The activation of bovine coagulation factor X. Methods Enzymol. 45 (1976) 95-107. [PMID: 1012042]

3. Davie, E.W., Fujikawa, K., Kurachi, K. and Kisiel, W. The role of serine proteases in the blood coagulation cascade. Adv. Enzymol. 48 (1979) 277-318. [PMID: 367103]

4. Jackson, C.M. and Nemerson, Y. Blood coagulation. Annu. Rev. Biochem. 49 (1980) 765-811. [PMID: 6996572]

5. McMullen, B.A., Fujikawa, K., Kisiel, W., Sasagawa, T., Howald, W.N., Kwa, E.Y. and Weinstein, B. Complete amino acid sequence of the light chain of human blood coagulation factor X: evidence for identification of residue 63 as β-hydroxyaspartic acid. Biochemistry 22 (1983) 2875-2884. [PMID: 6871167]

6. Cho, K., Tanaka, T., Cook, R.R., Kisiel, W., Fujikawa, K., Kurachi, K. and Powers, J.C. Active-site mapping of bovine and human blood coagulation serine proteases using synthetic peptide 4-nitroanilide and thio ester substrates. Biochemistry 23 (1984) 644-650. [PMID: 6370301]

[EC 3.4.21.6 created 1972, modified 2011]

*EC 3.4.21.60

Accepted name: scutelarin

Reaction: Selective cleavage of ArgThr and ArgIle in prothrombin to form thrombin and two inactive fragments

Other name(s): taipan activator; Oxyuranus scutellatus prothrombin-activating proteinase

Comments: From the venom of the Taipan snake (Oxyuranus scutellatus). Converts prothrombin to thrombin. Specificity is similar to that of Factor Xa (EC 3.4.21.6). However, unlike Factor Xa this enzyme can cleave its target in the absence of coagulation Factor Va. Activity is potentiated by phospholipid and Ca2+ which binds via γ-carboxyglutamic acid residues. Similar enzymes are known from the venom of other Australian elapid snakes, including Pseudonaja textilis textilis. Oxyuranus microlepidotus and Demansia nuchalis affinis.

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, CAS registry number: 93389-45-8

References:

1. Walker, F.J., Owen, W.G. and Esmon, C.T. Characterization of the prothrombin activator from the venom of Oxyuranus scutellatus scutellatus (taipan venom). Biochemistry 19 (1980) 1020-1023. [PMID: 6986908]

2. Speijer, H., Govers-Reimslag, J.W., Zwaal, R.F. and Rosing, J. Prothrombin activation by an activator from the venom of Oxyuranus scutellatus (taipan snake). J. Biol. Chem. 261 (1986) 13258-13267. [PMID: 3531198]

[EC 3.4.21.60 created 1978 as EC 3.4.99.28, transferred 1992 to EC 3.4.21.60, modified 2011]

*EC 3.5.1.100

Accepted name: (R)-amidase

Reaction: (1) (R)-piperazine-2-carboxamide + H2O = (R)-piperazine-2-carboxylic acid + NH3
(2) β-alaninamide + H2O = β-alanine + NH3

Other name(s): R-stereospecific amidase; R-amidase

Systematic name: (R)-piperazine-2-carboxamide amidohydrolase

Comments: In addition (R)-piperidine-3-carboxamide is hydrolysed to (R)-piperidine-3-carboxylic acid and NH3, and (R)-N-tert-butylpiperazine-2-carboxamide is hydrolysed to (R)-piperazine-2-carboxylic acid and tert-butylamine with lower activity. The enzyme does not act on the other amide substrates which are hydrolysed by EC 3.5.1.4 (amidase).

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number:

References:

1. Komeda, H., Harada, H., Washika, S., Sakamoto, T., Ueda, M. and Asano, Y. A novel R-stereoselective amidase from Pseudomonas sp. MCI3434 acting on piperazine-2-tert-butylcarboxamide. Eur. J. Biochem. 271 (2004) 1580-1590. [PMID: 15066183]

[EC 3.5.1.100 created 2009, modified 2011]

*EC 3.5.1.102

Accepted name: 2-amino-5-formylamino-6-ribosylaminopyrimidin-4(3H)-one 5'-monophosphate deformylase

Reaction: 2-amino-5-formylamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one + H2O = 2,5-diamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one + formate

Other name(s): ArfB

Systematic name: 2-amino-5-formylamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one amidohydrolase

Comments: The enzyme catalyses the second step in archaeal riboflavin and 7,8-didemethyl-8-hydroxy-5-deazariboflavin biosynthesis. The first step is catalysed by EC 3.5.4.29 (GTP cyclohydrolase IIa). The bacterial enzyme, EC 3.5.4.25 (GTP cyclohydrolase II) catalyses both reactions.

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number:

References:

1. Grochowski, L.L., Xu, H. and White, R.H. An iron(II) dependent formamide hydrolase catalyzes the second step in the archaeal biosynthetic pathway to riboflavin and 7,8-didemethyl-8-hydroxy-5-deazariboflavin. Biochemistry 48 (2009) 4181-4188. [PMID: 19309161]

[EC 3.5.1.102 created 2010, modified 2011]

EC 3.5.2.19

Accepted name: streptothricin hydrolase

Reaction: streptothricin-F + H2O = streptothricin-F acid

Other name(s): sttH (gene name)

Systematic name: streptothricin-F hydrolase

Comments: The enzyme also catalyses the hydrolysis of streptothricin-D to streptothricin-D acid [1]. The enzyme is responsible for streptothricin resistance in Streptomyces albulus and Streptomyces noursei [1,2].

References:

1. Maruyama, C. and Hamano, Y. The biological function of the bacterial isochorismatase-like hydrolase SttH. Biosci. Biotechnol. Biochem. 73 (2009) 2494-2500. [PMID: 19897889]

2. Hamano, Y., Matsuura, N., Kitamura, M. and Takagi, H. A novel enzyme conferring streptothricin resistance alters the toxicity of streptothricin D from broad-spectrum to bacteria-specific. J. Biol. Chem. 281 (2006) 16842-16848. [PMID: 16641084]

[EC 3.5.2.19 created 2011]

*EC 3.5.4.25

Accepted name: GTP cyclohydrolase II

Reaction: GTP + 3 H2O = formate + 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + diphosphate

Other name(s): guanosine triphosphate cyclohydrolase II; GTP-8-formylhydrolase

Systematic name: GTP 7,8-8,9-dihydrolase (diphosphate-forming)

Comments: Two C-N bonds are hydrolysed, releasing formate, with simultaneous removal of the terminal diphosphate.

Links to other databases: BRENDA, EXPASY, KEGG, PDB, CAS registry number: 56214-35-8

References:

1. Foor, F. and Brown, G.M. Purification and properties of guanosine triphosphate cyclohydrolase II from Escherichia coli. J. Biol. Chem. 250 (1975) 3545-3551. [PMID: 235552]

[EC 3.5.4.25 created 1984, modified 2011]

*EC 3.5.4.26

Accepted name: diaminohydroxyphosphoribosylaminopyrimidine deaminase

Reaction: 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine + H2O = 5-amino-6-(5-phospho-D-ribosylamino)uracil + NH3

Systematic name: 2,5-diamino-6-hydroxy-4-(5-phospho-D-ribosylamino)pyrimidine 2-aminohydrolase

Comments: The substrate is the product of EC 3.5.4.25 GTP cyclohydrolase II.

Links to other databases: BRENDA, EXPASY, KEGG, PDB, CAS registry number: 68994-19-4

References:

1. Burrows, R.B. and Brown, G.M. Presence of Escherichia coli of a deaminase and a reductase involved in biosynthesis of riboflavin. J. Bacteriol. 136 (1978) 657-667. [PMID: 30756]

[EC 3.5.4.26 created 1984, modified 2011]

*EC 3.5.4.29

Accepted name: GTP cyclohydrolase IIa

Reaction: GTP + 3 H2O = 2-amino-5-formylamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one + 2 phosphate

For diagram of reaction, click here

Systematic name: GTP 8,9-hydrolase (phosphate-forming)

Comments: Requires Mg2+. This enzyme catalyses the hydrolysis of the imidazole ring of guanosine 5'-triphosphate, N7-methylguanosine 5'-triphosphate or inosine 5'-triphosphate. Xanthosine 5'-triphosphate and ATP are not substrates. It also catalyses the hydrolysis of diphosphate to form two equivalents of phosphate. Unlike GTP cyclohydrolase II (EC 3.5.4.25), this enzyme does not release formate, but does hydrolyse the diphosphate from GTP to phosphate.

Links to other databases: BRENDA, EXPASY, KEGG, PDB, CAS registry number:

References:

1. Graham, D.E., Xu, H. and White, R.H. A member of a new class of GTP cyclohydrolases produces formylaminopyrimidine nucleotide monophosphates. Biochemistry 41 (2002) 15074-15084. [PMID: 12475257]

[EC 3.5.4.29 created 2003, modified 2011]

EC 3.5.99.8

Accepted name: 5-nitroanthranilic acid aminohydrolase

Reaction: 5-nitroanthranilate + H2O = 5-nitrosalicylate + NH3

Other name(s): naaA (gene name); 5NAA deaminase

Systematic name: 5-nitroanthranilate amidohydrolase

Comments: The enzyme catalyses the initial step in biodegradation of 5-nitroanthranilic acid by Bradyrhizobium sp. strain JS329.

References:

1. Qu, Y. and Spain, J.C. Biodegradation of 5-nitroanthranilic acid by Bradyrhizobium sp. strain JS329. Appl. Environ. Microbiol. 76 (2010) 1417-1422. [PMID: 20081004]

[EC 3.5.99.8 created 2011]

*EC 4.1.2.10

Accepted name: (R)-mandelonitrile lyase

Reaction: (R)-mandelonitrile = cyanide + benzaldehyde

Other name(s): (R)-oxynitrilase; oxynitrilase; D-oxynitrilase; D-α-hydroxynitrile lyase; mandelonitrile benzaldehyde-lyase; PaHNL; AtHNL; PhaMDL; (R)-HNL; (R)-PeHNL; (R)-hydroxynitrile lyase; R-selective hydroxynitrile lyase; R-selective HNL; (R)-(+)-mandelonitrile lyase

Systematic name: (R)-mandelonitrile benzaldehyde-lyase (cyanide-forming)

Comments: A variety of enzymes from different sources and with different properties. Some are flavoproteins, others are not. Active towards a number of aromatic and aliphatic hydroxynitriles (cyanohydrins).

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 9024-43-5

References:

1. Ueatrongchit, T., Kayo, A., Komeda, H., Asano, Y. and H-Kittikun, A. Purification and characterization of a novel (R)-hydroxynitrile lyase from Eriobotrya japonica (Loquat). Biosci. Biotechnol. Biochem. 72 (2008) 1513-1522. [PMID: 18540101]

2. Lin, G., Han, S. and Li, Z. Enzymic synthesis of (R)-cyanohydrins by three (R)-oxynitrilase sources in micro-aqueous organic medium. Tetrahedron 55 (1999) 3531-3540.

3. de Gonzalo, G., Brieva, R. and Gotor, V. (R)-Oxynitrilase-catalyzed transformation of ω-hydroxyalkanals. J. Mol. Catal. B 19-20 (2002) 223-230.

4. Ueatrongchit, T., Tamura, K., Ohmiya, T., H-Kittikun, A. and Asano, Y. Hydroxynitrile lyase from Passiflora edulis. Purification, characteristics and application in asymmetric synthesis of (R)-mandelonitrile. Enzyme Microb. Technol. 46 (2010) 456-465.

5. Andexer, J., von Langermann, J., Mell, A., Bocola, M., Kragl, U., Eggert, T. and Pohl, M. An R-selective hydroxynitrile lyase from Arabidopsis thaliana with an α/β-hydrolase fold. Angew. Chem. Int. Ed. Engl. 46 (2007) 8679-8681. [PMID: 17907254]

6. Guterl, J.K., Andexer, J.N., Sehl, T., von Langermann, J., Frindi-Wosch, I., Rosenkranz, T., Fitter, J., Gruber, K., Kragl, U., Eggert, T. and Pohl, M. Uneven twins: comparison of two enantiocomplementary hydroxynitrile lyases with α/β-hydrolase fold. J. Biotechnol. 141 (2009) 166-173. [PMID: 19433222]

[EC 4.1.2.10 created 1961, modified 1999, modified 2011]

[EC 4.1.2.37 Deleted entry: hydroxynitrilase. Now covered by EC 4.1.2.46 [aliphatic (R)-hydroxynitrile lyase] and EC 4.1.2.47 [(S)-hydroxynitrile ketone-lyase (cyanide forming)] (EC 4.1.2.37 created 1992 (EC 4.1.2.39 created 1999, incorporated 2007), deleted 2011)]

*EC 4.1.2.45

Accepted name: trans-o-hydroxybenzylidenepyruvate hydratase-aldolase

Reaction: (3E)-4-(2-hydroxyphenyl)-2-oxobut-3-enoate + H2O = salicylaldehyde + pyruvate

For diagram of reaction, click here

Glossary: (3E)-4-(2-hydroxyphenyl)-2-oxobut-3-enoate = (E)-2'-hydroxybenzylidenepyruvate

salicylaldehyde = 2-hydroxybenzaldehyde

Other name(s): 2'-hydroxybenzalpyruvate aldolase; NsaE; tHBPA hydratase-aldolase

Systematic name: (3E)-4-(2-hydroxyphenyl)-2-oxobut-3-enoate hydro-lyase

Comments: This enzyme is involved in naphthalene degradation. The enzyme catalyses a retro-aldol reaction in vitro, and it accepts a broad range of aldehydes and 4-substituted 2-oxobut-3-enoates as substrates [4].

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number:

References:

1. Kuhm, A.E., Knackmuss, H.J. and Stolz, A. Purification and properties of 2'-hydroxybenzalpyruvate aldolase from a bacterium that degrades naphthalenesulfonates. J. Biol. Chem. 268 (1993) 9484-9489. [PMID: 8486638]

2. Keck, A., Conradt, D., Mahler, A., Stolz, A., Mattes, R. and Klein, J. Identification and functional analysis of the genes for naphthalenesulfonate catabolism by Sphingomonas xenophaga BN6. Microbiology 152 (2006) 1929-1940. [PMID: 16804169]

3. Eaton, R.W. Organization and evolution of naphthalene catabolic pathways: sequence of the DNA encoding 2-hydroxychromene-2-carboxylate isomerase and trans-o-hydroxybenzylidenepyruvate hydratase-aldolase from the NAH7 plasmid. J. Bacteriol. 176 (1994) 7757-7762. [PMID: 8002605]

4. Eaton, R.W. trans-o-Hydroxybenzylidenepyruvate hydratase-aldolase as a biocatalyst. Appl. Environ. Microbiol. 66 (2000) 2668-2672. [PMID: 10831455]

[EC 4.1.2.45 created 2010, modified 2011]

EC 4.1.2.46

Accepted name: aliphatic (R)-hydroxynitrile lyase

Reaction: (2R)-2-hydroxy-2-methylbutanenitrile = cyanide + butan-2-one

Other name(s): (R)-HNL; (R)-oxynitrilase; (R)-hydroxynitrile lyase; LuHNL

Systematic name: (2R)-2-hydroxy-2-methylbutanenitrile butan-2-one-lyase (cyanide forming)

Comments: The enzyme contains Zn2+ [1]. The enzyme catalyses the stereoselective synthesis of aliphatic (R)-cyanohydrins [1]. No activity towards mandelonitrile and 4-hydroxymandelonitrile [5]. Natural substrates for the (R)-oxynitrilase from Linum usitatissimum are acetone and butan-2-one, which are the building blocks of the cyanogen glycosides in Linum, linamarin and lotaustralin, or linustatin and neolinustatin, respectively [4].

References:

1. Trummler, K., Roos, J., Schwaneberg, U., Effenberger, F., Fšrster, S., Pfizenmaier, K., Wajant, H. Expression of the Zn2+-containing hydroxynitrile lyase from flax (Linum usitatissimum) in Pichia pastoris - utilization of the recombinant enzyme for enzymatic analysis and site-directed mutagenesis. Plant Sci. 139 (1998) 19-27.

2. Trummler, K. and Wajant, H. Molecular cloning of acetone cyanohydrin lyase from flax (Linum usitatissimum). Definition of a novel class of hydroxynitrile lyases. J. Biol. Chem. 272 (1997) 4770-4774. [PMID: 9030531]

3. Albrecht, J., Jansen, I.and Kula, M.R. Improved purification of an (R)-oxynitrilase from Linum usitatissimum (flax) and investigation of the substrate range. Biotechnol. Appl. Biochem. 17 (1993) 191-203.

4. Xu, L.-L., Singh, B.K. and Conn, E.E. Purification and characterization of acetone cyanohydrin lyase from Linum usitatissimum. Arch. Biochem. Biophys. 263 (1988) 256-263. [PMID: 3377504]

5. Cabirol, F.L., Tan, P.L., Tay, B., Cheng, S., Hanefeld, U. and Sheldon, R.A. Linum usitatissimum hydroxynitrile lyase cross-linked enzyme aggregates: a recyclable enantioselective catalyst. Adv. Synth. Catal. 350 (2008) 2329-2338.

6. Breithaupt, H., Pohl, M., Bšnigk, W., Heim, P., Schimz, K.-L. and Kula, M.-R. Cloning and expression of (R)-hydroxynitrile lyase from Linum usitatissimum (flax). J. Mol. Catal. B 6 (1999) 315-332.

[EC 4.1.2.46 created 2011]

EC 4.1.2.47

Accepted name: (S)-hydroxynitrile lyase

Reaction: (1) an aliphatic (S)-hydroxynitrile = cyanide + an aliphatic aldehyde or ketone
(2) an aromatic (S)-hydroxynitrile = cyanide + an aromatic aldehyde

Other name(s): (S)-cyanohydrin producing hydroxynitrile lyase; (S)-oxynitrilase; (S)-HbHNL; (S)-MeHNL; hydroxynitrile lyase; oxynitrilase; HbHNL; MeHNL; (S)-selective hydroxynitrile lyase; (S)-cyanohydrin carbonyl-lyase (cyanide forming)

Systematic name: (S)-cyanohydrin lyase (cyanide forming)

Comments: Hydroxynitrile lyases catalyses the the cleavage of hydroxynitriles into cyanide and the corresponding aldehyde or ketone. In nature the liberation of cyanide serves as a defense mechanism against herbivores and microbial attack in plants. In vitro the enzymes from Manihot esculenta and Hevea brasiliensis accept a broad range of aliphatic and aromatic carbonyl compounds as substrates and catalyse the formation of (S)-hydroxynitriles [1,10].

References:

1. Förster, S., Roos, J., Effenberger, F., Wajant, H. and Sprauer, A. The first recombinant hydroxynitrile lyase and its application in the synthesis of (S)-cyanohydrins. Angew. Chem. Int. Ed. 35 (1996) 437-439.

2. Bühler, H., Effenberger, F., Förster, S., Roos, J. and Wajant, H. Substrate specificity of mutants of the hydroxynitrile lyase from Manihot esculenta. Chembiochem. 4 (2003) 211-216. [PMID: 12616635]

3. Semba, H., Dobashi, Y. and Matsui, T. Expression of hydroxynitrile lyase from Manihot esculenta in yeast and its application in (S)-mandelonitrile production using an immobilized enzyme reactor. Biosci. Biotechnol. Biochem. 72 (2008) 1457-1463. [PMID: 18540112]

4. Avi, M., Wiedner, R.M., Griengl, H. and Schwab, H. Improvement of a stereoselective biocatalytic synthesis by substrate and enzyme engineering: 2-hydroxy-(4'-oxocyclohexyl)acetonitrile as the model. Chemistry 14 (2008) 11415-11422. [PMID: 19006143]

5. von Langermann, J., Guterl, J.K., Pohl, M., Wajant, H. and Kragl, U. Hydroxynitrile lyase catalyzed cyanohydrin synthesis at high pH-values. Bioprocess Biosyst Eng 31 (2008) 155-161. [PMID: 18204865]

6. Schmidt, A., Gruber, K., Kratky, C. and Lamzin, V.S. Atomic resolution crystal structures and quantum chemistry meet to reveal subtleties of hydroxynitrile lyase catalysis. J. Biol. Chem. 283 (2008) 21827-21836. [PMID: 18524775]

7. Gartler, G., Kratky, C. and Gruber, K. Structural determinants of the enantioselectivity of the hydroxynitrile lyase from Hevea brasiliensis. J. Biotechnol. 129 (2007) 87-97. [PMID: 17250917]

8. Wagner, U.G., Schall, M., Hasslacher, M., Hayn, M., Griengl, H., Schwab, H. and Kratky, C. Crystallization and preliminary X-ray diffraction studies of a hydroxynitrile lyase from Hevea brasiliensis. Acta Crystallogr. D Biol. Crystallogr. 52 (1996) 591-593. [PMID: 15299689]

9. Schmidt, M., Herve, S., Klempier, N. and Griengl, H. Preparation of optically active cyanohydrins using the (S)-hydroxynitrile lyase from Hevea brasiliensis. Tetrahedron 52 (1996) 7833-7840.

10. Klempier, N. and Griengl, H. Aliphatic (S)-cyanohydrins by enzyme catalyzed synthesis. Tetrahedron Lett. 34 (1993) 4769-4772.

[EC 4.1.2.47 created 2011]

*EC 4.1.3.14

Accepted name: L-erythro-3-hydroxyaspartate aldolase

Reaction: L-erythro-3-hydroxy-aspartate = glycine + glyoxylate

Other name(s): L-erythro-β-hydroxyaspartate aldolase; L-erythro-β-hydroxyaspartate glycine-lyase; erythro-3-hydroxy-Ls-aspartate glyoxylate-lyase

Systematic name: L-erythro-3-hydroxy-aspartate glyoxylate-lyase (glycine-forming)

Comments: A pyridoxal-phosphate protein. The enzyme, purified from the bacterium Paracoccus denitrificans NCIMB 8944, is strictly specific for the L-erythro stereoisomer of 3-hydroxyaspartate. Different from EC 4.1.3.41, erythro-3-hydroxy-D-aspartate aldolase. Requires a divalent cation.

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 37290-64-5

References:

1. Gibbs, R.G. and Morris, J.G. Assay and properties of β-hydroxyaspartate aldolase from Micrococcus denitrificans. Biochim. Biophys. Acta 85 (1964) 501-503. [PMID: 14194868]

[EC 4.1.3.14 created 1972, modified 2011]

EC 4.1.3.41

Accepted name: 3-hydroxy-D-aspartate aldolase

Reaction: (1) threo-3-hydroxy-D-aspartate = glycine + glyoxylate
(2) D-erythro-3-hydroxyaspartate = glycine + glyoxylate

Other name(s): D-3-hydroxyaspartate aldolase

Systematic name: 3-hydroxy-D-aspartate glyoxylate-lyase (glycine-forming)

Comments: A pyridoxal-phosphate protein. The enzyme, purified from the bacterium Paracoccus denitrificans IFO 13301, is strictly D-specific as to the α-position of the substrate, but accepts both the threo and erythro forms at the β-position. The erythro form is a far better substrate (about 100 fold). The enzyme can also accept D-allothreonine, D-threonine, erythro-3-phenyl-D-serine and threo-3-phenyl-D-serine. Different from EC 4.1.3.14, erythro-3-hydroxy-L-aspartate aldolase. Requires a divalent cation, such as Mg2+, Mn2+ or Co2+.

References:

1. Liu, J.Q., Dairi, T., Itoh, N., Kataoka, M. and Shimizu, S. A novel enzyme, D-3-hydroxyaspartate aldolase from Paracoccus denitrificans IFO 13301: purification, characterization, and gene cloning. Appl. Microbiol. Biotechnol. 62 (2003) 53-60. [PMID: 12835921]

[EC 4.1.3.41 created 2011]

*EC 4.1.99.5

Accepted name: octadecanal decarbonylase

Reaction: octadecanal + reduced ferredoxin = heptadecane + CO + oxidized ferredoxin

Other name(s): decarbonylase; aldehyde decarbonylase

Systematic name: octadecanal alkane-lyase

Comments: Involved in the biosynthesis of alkanes. The enzyme from the cyanobacterium Nostoc punctiforme PCC 73102 requires reduced ferredoxin for activity, and produces mostly C15 to C17 alkanes [2]. The enzyme from pea (Pisum sativum) produces alkanes of chain length C18 to C32 and is inhibited by metal-chelating agents [1]. The substrate for this enzyme is formed by EC 1.2.1.80, acyl-[acyl-carrier protein] reductase.

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 94185-90-7

References:

1. Cheesbrough, T.M. and, K olattukudy, P.E. Alkane biosynthesis by decarbonylation of aldehydes catalyzed by a particulate preparation from Pisum sativum. Proc. Natl. Acad. Sci. USA 81 (1984) 6613-6617. [PMID: 6593720]

2. Schirmer, A., Rude, M.A., Li, X., Popova, E. and del Cardayre, S.B. Microbial biosynthesis of alkanes. Science 329 (2010) 559-562. [PMID: 20671186]

[EC 4.1.99.5 created 1989, modified 2011]

EC 4.2.1.121

Accepted name: colneleate synthase

Reaction: (9S,10E,12Z)-9-hydroperoxyoctadeca-10,12-dienoate = (8E)-9-[(1E,3Z)-nona-1,3-dien-1-yloxy]non-8-enoate + H2O

Glossary: colneleate = (8E)-9-[(1E,3Z)-nona-1,3-dien-1-yloxy]non-8-enoate

Other name(s): 9-divinyl ether synthase; 9-DES; CYP74D; CYP74D1; CYP74 cytochrome P-450; DES1

Systematic name: (8E)-9-[(1E,3E)-nona-1,3-dien-1-yloxy]non-8-enoate synthase

Comments: A heme-thiolate protein (P450) [2]. It catalyses the selective removal of pro-R hydrogen at C-8 in the biosynthesis of colneleic acid [4]. It forms also (8E)-9-[(1E,3Z,6Z)-nona-1,3,6-trien-1-yloxy]non-8-enoic acid (i.e. colnelenate) from (9S,10E,12Z,15Z)-9-hydroperoxy-10,12,15-octadecatrienoate. The corresponding 13-hydroperoxides are poor substrates [1,3]. The divinyl ethers colneleate and colnelenate have antimicrobial activity.

References:

1. Stumpe, M., Kandzia, R., Gobel, C., Rosahl, S. and Feussner, I. A pathogen-inducible divinyl ether synthase (CYP74D) from elicitor-treated potato suspension cells. FEBS Lett. 507 (2001) 371-376. [PMID: 11696374]

2. Itoh, A. and Howe, G.A. Molecular cloning of a divinyl ether synthase. Identification as a CYP74 cytochrome P-450. J. Biol. Chem. 276 (2001) 3620-3627. [PMID: 11060314]

3. Fammartino, A., Cardinale, F., Gobel, C., Mene-Saffrane, L., Fournier, J., Feussner, I. and Esquerre-Tugaye, M.T. Characterization of a divinyl ether biosynthetic pathway specifically associated with pathogenesis in tobacco. Plant Physiol. 143 (2007) 378-388. [PMID: 17085514]

4. Hamberg, M. Hidden stereospecificity in the biosynthesis of divinyl ether fatty acids. FEBS J. 272 (2005) 736-743. [PMID: 15670154]

[EC 4.2.1.121 created 2011]

*EC 4.3.1.16

Accepted name: threo-3-hydroxy-L-aspartate ammonia-lyase

Reaction: threo-3-hydroxy-L-aspartate = oxaloacetate + NH3

Other name(s): L-threo-3-hydroxyaspartate dehydratase; threo-3-hydroxyaspartate ammonia-lyase

Systematic name: threo-3-hydroxy-L-aspartate ammonia-lyase (oxaloacetate-forming)

Comments: A pyridoxal-phosphate protein. The enzyme, purified from the bacterium Pseudomonas sp. T62, is highly specific, and does not accept any other stereoisomer of 3-hydroxyaspartate. Different from EC 4.3.1.20, erythro-3-hydroxy-L-aspartate ammonia-lyase and EC 4.3.1.27, threo-3-hydroxy-D-aspartate ammonia-lyase. Requires a divalent cation such as Mn2+, Mg2+, or Ca2+.

Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 248270-70-4

References:

1. Wada, M., Matsumoto, T., Nakamori, S., Sakamoto, M., Kataoka, M., Liu, J.-Q., Itoh, N., Yamada, H. and Shimizu, S. Purification and characterization of a novel enzyme, L-threo-3-hydroxyaspartate dehydratase, from Pseudomonas sp. T62. FEMS Microbiol. Lett. 179 (1999) 147-151. [PMID: 10481099]

[EC 4.3.1.16 created 2001, modified 2011]

*EC 4.3.1.20

Accepted name: erythro-3-hydroxy-L-aspartate ammonia-lyase

Reaction: erythro-3-hydroxy-L-aspartate = oxaloacetate + NH3

Other name(s): erythro-β-hydroxyaspartate dehydratase; erythro-3-hydroxyaspartate dehydratase; erythro-3-hydroxy-Ls-aspartate hydro-lyase (deaminating); erythro-3-hydroxy-Ls-aspartate ammonia-lyase

Systematic name: erythro-3-hydroxy-L-aspartate ammonia-lyase (oxaloacetate-forming)

Comments: A pyridoxal-phosphate protein. The enzyme, which was characterized from the bacterium Paracoccus denitrificans NCIMB 8944, is highly specific for the L-isomer of erythro-3-hydroxyaspartate. Different from EC 4.3.1.16, threo-3-hydroxy-L-aspartate ammonia-lyase and EC 4.3.1.27, threo-3-hydroxy-D-aspartate ammonia-lyase. Requires a divalent cation such as Mn2+, Mg2+, or Ca2+.

Links to other databases: BRENDA, EXPASY, KEGG, METACYC, CAS registry number: 37290-74-7

References:

1. Gibbs, R.G. and Morris, J.G. Purification and properties of erythro-β-hydroxyaspartate dehydratase from Micrococcus denitrificans. Biochem. J. 97 (1965) 547-554. [PMID: 16749162]

[EC 4.3.1.20 created 1972 as EC 4.2.1.38, transfered 2001 to EC 4.3.1.20, modified 2011]

EC 4.3.1.27

Accepted name: threo-3-hydroxy-D-aspartate ammonia-lyase

Reaction: threo-3-hydroxy-D-aspartate = oxaloacetate + NH3

Other name(s): D-threo-3-hydroxyaspartate dehydratase

Systematic name: threo-3-hydroxy-D-aspartate ammonia-lyase (oxaloacetate-forming)

Comments: A pyridoxal-phosphate protein. The enzyme, purified from the bacterium Delftia sp. HT23, also has activity against L-threo-3-hydroxyaspartate, L-erythro-3-hydroxyaspartate, and D-serine. Different from EC 4.3.1.20, erythro-3-hydroxy-L-aspartate ammonia-lyase and EC 4.3.1.16, threo-3-hydroxy-L-aspartate ammonia-lyase. Requires a divalent cation such as Mn2+, Co2+ or Ni2+.

References:

1. Maeda, T., Takeda, Y., Murakami, T., Yokota, A. and Wada, M. Purification, characterization and amino acid sequence of a novel enzyme, D-threo-3-hydroxyaspartate dehydratase, from Delftia sp. HT23. J. Biochem. 148 (2010) 705-712. [PMID: 20843822]

[EC 4.3.1.27 created 2011]

EC 6.3.2.36

Accepted name: 4-phosphopantoate—β-alanine ligase

Reaction: ATP + (R)-4-phosphopantoate + β-alanine = AMP + diphosphate + (R)-4'-phosphopantothenate

Other name(s): phosphopantothenate synthetase; TK1686 protein

Systematic name: (R)-4-phosphopantoate:β-alanine ligase (AMP-forming)

Comments: The conversion of (R)-pantoate to (R)-4'-phosphopantothenate is part of the pathway leading to biosynthesis of 4'-phosphopantetheine, an essential cofactor of coenzyme A and acyl-carrier protein. In bacteria and eukaryotes this conversion is performed by condensation with β-alanine, followed by phosphrylation (EC 6.3.2.1 [pantoate—β-alanine ligase] and EC 2.7.1.33 [pantothenate kinase], respectively). In archaea the order of these two steps is reversed, and phosphorylation precedes condensation with β-alanine. The two archaeal enzymes that catalyse this conversion are EC 2.7.1.169, pantoate kinase, and this enzyme.

References:

1. Yokooji, Y., Tomita, H., Atomi, H. and Imanaka, T. Pantoate kinase and phosphopantothenate synthetase, two novel enzymes necessary for CoA biosynthesis in the Archaea. J. Biol. Chem. 284 (2009) 28137-28145. [PMID: 19666462]

[EC 6.3.2.36 created 2011]