Proposed Changes to the Enzyme List

References:

1.	Koeduka, T., Fridman, E., Gang, D.R., Vassão, D.G., Jackson, B.L., Kish, C.M., Orlova, I., Spassova, S.M., Lewis, N.G., Noel, J.P., Baiga, T.J., Dudareva, N. and Pichersky, E. Eugenol and isoeugenol, characteristic aromatic constituents of spices, are biosynthesized via reduction of a coniferyl alcohol ester. Proc. Natl. Acad. Sci. USA 103 (2006) 10128–10133. [DOI] [PMID: 16782809]
2.	Vassão, D.G., Kim, S.J., Milhollan, J.K., Eichinger, D., Davin, L.B. and Lewis, N.G. A pinoresinol-lariciresinol reductase homologue from the creosote bush (Larrea tridentata) catalyzes the efficient in vitro conversion of p-coumaryl/coniferyl alcohol esters into the allylphenols chavicol/eugenol, but not the propenylphenols p-anol/isoeugenol. Arch. Biochem. Biophys. 465 (2007) 209–218. [DOI] [PMID: 17624297]
3.	Louie, G.V., Baiga, T.J., Bowman, M.E., Koeduka, T., Taylor, J.H., Spassova, S.M., Pichersky, E. and Noel, J.P. Structure and reaction mechanism of basil eugenol synthase. PLoS One 2 (2007) e993. [DOI] [PMID: 17912370]
4.	Koeduka, T., Louie, G.V., Orlova, I., Kish, C.M., Ibdah, M., Wilkerson, C.G., Bowman, M.E., Baiga, T.J., Noel, J.P., Dudareva, N. and Pichersky, E. The multiple phenylpropene synthases in both Clarkia breweri and Petunia hybrida represent two distinct protein lineages. Plant J. 54 (2008) 362–374. [DOI] [PMID: 18208524]
5.	Koeduka, T., Baiga, T.J., Noel, J.P. and Pichersky, E. Biosynthesis of t-anethole in anise: characterization of t-anol/isoeugenol synthase and an O-methyltransferase specific for a C₇-C₈ propenyl side chain. Plant Physiol. 149 (2009) 384–394. [DOI] [PMID: 18987218]

[EC 1.1.1.318 created 2012]

1.1.1.319

Accepted name:

isoeugenol synthase

Reaction:

isoeugenol + acetate + NADP⁺ = coniferyl acetate + NADPH + H⁺

Other name(s):

IGS1; t-anol/isoeugenol synthase 1

Systematic name:

eugenol:NADP⁺ oxidoreductase (coniferyl acetate reducing)

Comments:

The enzyme acts in the opposite direction. In Ocimum basilicum (sweet basil), Clarkia breweri and Petunia hybrida only isoeugenol is formed [1,2]. However in Pimpinella anisum (anise) only anol is formed in vivo, although the cloned enzyme does produce isoeugenol [3].

Links to other databases:

References:

1.	Koeduka, T., Fridman, E., Gang, D.R., Vassão, D.G., Jackson, B.L., Kish, C.M., Orlova, I., Spassova, S.M., Lewis, N.G., Noel, J.P., Baiga, T.J., Dudareva, N. and Pichersky, E. Eugenol and isoeugenol, characteristic aromatic constituents of spices, are biosynthesized via reduction of a coniferyl alcohol ester. Proc. Natl. Acad. Sci. USA 103 (2006) 10128–10133. [DOI] [PMID: 16782809]
2.	Koeduka, T., Louie, G.V., Orlova, I., Kish, C.M., Ibdah, M., Wilkerson, C.G., Bowman, M.E., Baiga, T.J., Noel, J.P., Dudareva, N. and Pichersky, E. The multiple phenylpropene synthases in both Clarkia breweri and Petunia hybrida represent two distinct protein lineages. Plant J. 54 (2008) 362–374. [DOI] [PMID: 18208524]
3.	Koeduka, T., Baiga, T.J., Noel, J.P. and Pichersky, E. Biosynthesis of t-anethole in anise: characterization of t-anol/isoeugenol synthase and an O-methyltransferase specific for a C₇-C₈ propenyl side chain. Plant Physiol. 149 (2009) 384–394. [DOI] [PMID: 18987218]

[EC 1.1.1.319 created 2012]

1.1.1.320

Accepted name:

benzil reductase [(S)-benzoin forming]

Reaction:

(S)-benzoin + NADP⁺ = benzil + NADPH + H⁺

Glossary:

(S)-benzoin = (2S)-2-hydroxy-1,2-diphenylethanone
benzil = 1,2-diphenylethane-1,2-dione

Other name(s):

YueD

Systematic name:

(S)-benzoin:NADP⁺ oxidoreductase

Comments:

The enzyme also reduces 1-phenylpropane-1,2-dione. The enzyme from Bacillus cereus in addition reduces 1,4-naphthoquinone and 1-(4-methylphenyl)-2-phenylethane-1,2-dione with high efficiency [2].

Links to other databases:

References:

1.	Maruyama, R., Nishizawa, M., Itoi, Y., Ito, S. and Inoue, M. Isolation and expression of a Bacillus cereus gene encoding benzil reductase. Biotechnol. Bioeng. 75 (2001) 630–633. [PMID: 11745140]
2.	Maruyama, R., Nishizawa, M., Itoi, Y., Ito, S. and Inoue, M. The enzymes with benzil reductase activity conserved from bacteria to mammals. J. Biotechnol. 94 (2002) 157–169. [DOI] [PMID: 11796169]

[EC 1.1.1.320 created 2012]

1.1.1.321

Accepted name:

benzil reductase [(R)-benzoin forming]

Reaction:

(R)-benzoin + NADP⁺ = benzil + NADPH + H⁺

Glossary:

(R)-benzoin = (2R)-2-hydroxy-1,2-diphenylethanone
benzil = 1,2-diphenylethane-1,2-dione

Systematic name:

(R)-benzoin:NADP⁺ oxidoreductase

Comments:

The enzyme from the bacterium Xanthomonas oryzae is able to reduce enantioselectively only one of the two carbonyl groups of benzil to give optically active (R)-benzoin.

Links to other databases:

References:

1.	Konishi, J., Ohta, H. and Tuchihashi, G. Asymmetric reduction of benzil to benzoin catalyzed by the enzyme system of a microorganism. Chem. Lett. 14 (1985) 1111–1112.

[EC 1.1.1.321 created 2012]

1.1.1.322

Accepted name:

(–)-endo-fenchol dehydrogenase

Reaction:

(–)-endo-fenchol + NAD(P)⁺ = (+)-fenchone + NAD(P)H + H⁺

For diagram of pinene and related monoterpenoids, click here

Other name(s):

l-endo-fenchol dehydrogenase; FDH

Systematic name:

(–)-endo-fenchol:NAD(P)⁺ oxidoreductase

Comments:

Isolated from the plant Foeniculum vulgare (fennel). NADH is slightly preferred to NADPH.

Links to other databases:

References:

1.	Croteau, R. and Felton, N.M. Substrate specificity of monoterpenol dehydrogenases from Foeniculum vulgare and Tanacetum vulgare. Phytochemistry 19 (1980) 1343–1347.

[EC 1.1.1.322 created 2012]

1.1.1.323

Accepted name:

(+)-thujan-3-ol dehydrogenase

Reaction:

(+)-thujan-3-ol + NAD(P)⁺ = (+)-thujan-3-one + NAD(P)H + H⁺

Other name(s):

d-3-thujanol dehydrogenase; TDH

Systematic name:

(+)-thujan-3-ol:NAD(P)⁺ oxidoreductase

Comments:

Isolated from the plant Tanacetum vulgare (tansy). NADH is preferred to NADPH.

Links to other databases:

References:

1.	Croteau, R. and Felton, N.M. Substrate specificity of monoterpenol dehydrogenases from Foeniculum vulgare and Tanacetum vulgare. Phytochemistry 19 (1980) 1343–1347.

[EC 1.1.1.323 created 2012]

1.1.1.324

Accepted name:

8-hydroxygeraniol dehydrogenase

Reaction:

(6E)-8-hydroxygeraniol + 2 NADP⁺ = (6E)-8-oxogeranial + 2 NADPH + 2 H⁺ (overall reaction)
(1a) (6E)-8-hydroxygeraniol + NADP⁺ = (6E)-8-hydroxygeranial + NADPH + H⁺
(1b) (6E)-8-hydroxygeraniol + NADP⁺ = (6E)-8-oxogeraniol + NADPH + H⁺
(1c) (6E)-8-hydroxygeranial + NADP⁺ = (6E)-8-oxogeranial + NADPH + H⁺
(1d) (6E)-8-oxogeraniol + NADP⁺ = (6E)-8-oxogeranial + NADPH + H⁺

For diagram of acyclic monoterpenoid biosynthesis, click here

Other name(s):

8-hydroxygeraniol oxidoreductase; CYP76B10; G10H; CrG10H; SmG10H; acyclic monoterpene primary alcohol:NADP⁺ oxidoreductase

Systematic name:

(6E)-8-hydroxygeraniol:NADP⁺ oxidoreductase

Comments:

Contains Zn²⁺. The enzyme catalyses the oxidation of (6E)-8-hydroxygeraniol to (6E)-8-oxogeranial via either (6E)-8-hydroxygeranial or (6E)-8-oxogeraniol. Also acts on geraniol, nerol and citronellol. May be identical to EC 1.1.1.183 geraniol dehydrogenase. The recommended numbering of geraniol gives 8-hydroxygeraniol as the substrate rather than 10-hydroxygeraniol as used by references 1 and 2. See prenol nomenclature Pr-1.

Links to other databases:

References:

1.	Ikeda, H., Esaki, N., Nakai, S., Hashimoto, K., Uesato, S., Soda, K. and Fujita, T. Acyclic monoterpene primary alcohol:NADP⁺ oxidoreductase of Rauwolfia serpentina cells: the key enzyme in biosynthesis of monoterpene alcohols. J. Biochem. 109 (1991) 341–347. [PMID: 1864846]
2.	Hallahan, D.L., West, J.M., Wallsgrove, R.M., Smiley, D.W., Dawson, G.W., Pickett, J.A. and Hamilton, J.G. Purification and characterization of an acyclic monoterpene primary alcohol:NADP⁺ oxidoreductase from catmint (Nepeta racemosa). Arch. Biochem. Biophys. 318 (1995) 105–112. [DOI] [PMID: 7726550]

[EC 1.1.1.324 created 2012]

1.1.1.325

Accepted name:

sepiapterin reductase (L-threo-7,8-dihydrobiopterin-forming)

Reaction:

(1) L-threo-7,8-dihydrobiopterin + NADP⁺ = sepiapterin + NADPH + H⁺
(2) L-threo-tetrahydrobiopterin + 2 NADP⁺ = 6-pyruvoyl-5,6,7,8-tetrahydropterin + 2 NADPH + 2 H⁺

Glossary:

sepiapterin = 2-amino-6-lactoyl-7,8-dihydropteridin-4(3H)-one
tetrahydrobiopterin = 5,6,7,8-tetrahydrobiopterin = 2-amino-6-(1,2-dihydroxypropyl)-5,6,7,8-tetrahydropteridin-4(3H)-one

Systematic name:

L-threo-7,8-dihydrobiopterin:NADP⁺ oxidoreductase

Comments:

This enzyme, isolated from the bacterium Chlorobium tepidum, catalyses the final step in the de novo synthesis of tetrahydrobiopterin from GTP. cf. EC 1.1.1.153, sepiapterin reductase (L-erythro-7,8-dihydrobiopterin-forming).

Links to other databases:

BRENDA, EXPASY, GTD, KEGG, PDB, CAS registry number: 9059-48-7

References:

1.	Cho, S.H., Na, J.U., Youn, H., Hwang, C.S., Lee, C.H. and Kang, S.O. Sepiapterin reductase producing L-threo-dihydrobiopterin from Chlorobium tepidum. Biochem. J. 340 (1999) 497–503. [PMID: 10333495]
2.	Supangat, S., Choi, Y.K., Park, Y.S., Son, D., Han, C.D. and Lee, K.H. Expression, purification, crystallization and preliminary X-ray analysis of sepiapterin reductase from Chlorobium tepidum. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 61 (2005) 202–204. [DOI] [PMID: 16510994]

[EC 1.1.1.325 created 2012]

1.1.1.326

Accepted name:

zerumbone synthase

Reaction:

10-hydroxy-α-humulene + NAD⁺ = zerumbone + NADH + H⁺

For diagram of zerumbone biosynthesis, click here

Other name(s):

ZSD1

Systematic name:

10-hydroxy-α-humulene:NAD⁺ oxidoreductase

Comments:

The enzyme was cloned from shampoo ginger, Zingiber zerumbet.

Links to other databases:

References:

1.	Okamoto, S., Yu, F., Harada, H., Okajima, T., Hattan, J., Misawa, N. and Utsumi, R. A short-chain dehydrogenase involved in terpene metabolism from Zingiber zerumbet. FEBS J. 278 (2011) 2892–2900. [DOI] [PMID: 21668645]

[EC 1.1.1.326 created 2012]

1.3.8.3

Accepted name:

(R)-benzylsuccinyl-CoA dehydrogenase

Reaction:

(R)-2-benzylsuccinyl-CoA + electron-transfer flavoprotein = (E)-2-benzylidenesuccinyl-CoA + reduced electron-transfer flavoprotein

For diagram of anaerobic toluene catabolism, click here

Other name(s):

BbsG; (R)-benzylsuccinyl-CoA:(acceptor) oxidoreductase

Systematic name:

(R)-benzylsuccinyl-CoA:electron transfer flavoprotein oxidoreductase

Comments:

Contains a tightly-bound FAD cofactor. Unlike other acyl-CoA dehydrogenases, this enzyme exhibits high substrate- and enantiomer specificity; it is highly specific for (R)-benzylsuccinyl-CoA and is inhibited by (S)-benzylsuccinyl-CoA. Forms the third step in the anaerobic toluene metabolic pathway in Thauera aromatica. Ferricenium ion is an effective artificial electron acceptor.

Links to other databases:

BRENDA, EAWAG-BBD, EXPASY, Gene, KEGG

References:

1.	Leutwein, C. and Heider, J. Anaerobic toluene-catabolic pathway in denitrifying Thauera aromatica: activation and β-oxidation of the first intermediate, (R)-(+)-benzylsuccinate. Microbiology 145 (1999) 3265–3271. [DOI] [PMID: 10589736]
2.	Leutwein, C. and Heider, J. (R)-Benzylsuccinyl-CoA dehydrogenase of Thauera aromatica, an enzyme of the anaerobic toluene catabolic pathway. Arch. Microbiol. 178 (2002) 517–524. [DOI] [PMID: 12420174]

[EC 1.3.8.3 created 2003 as EC 1.3.99.21, transferred 2012 to EC 1.3.8.3]

1.3.8.4

Accepted name:

isovaleryl-CoA dehydrogenase

Reaction:

isovaleryl-CoA + electron-transfer flavoprotein = 3-methylcrotonyl-CoA + reduced electron-transfer flavoprotein

Other name(s):

isovaleryl-coenzyme A dehydrogenase; isovaleroyl-coenzyme A dehydrogenase; 3-methylbutanoyl-CoA:(acceptor) oxidoreductase

Systematic name:

3-methylbutanoyl-CoA:electron-transfer flavoprotein oxidoreductase

Comments:

Contains a tightly-bound FAD cofactor. Pentanoate can act as donor.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, PDB, CAS registry number: 37274-61-6

References:

1.	Bachhawat, B.K., Robinson, W.G. and Coon, M.J. Enzymatic carboxylation of β-hydroxyisovaleryl coenzyme A. J. Biol. Chem. 219 (1956) 539–550. [PMID: 13319276]
2.	Ikeda, Y. and Tanaka, K. Purification and characterization of isovaleryl coenzyme A dehydrogenase from rat liver mitochondria. J. Biol. Chem. 258 (1983) 1077–1085. [PMID: 6401713]
3.	Tanaka, K., Budd, M.A., Efron, M.L. and Isselbacher, K.J. Isovaleric acidemia: a new genetic defect of leucine metabolism. Proc. Natl. Acad. Sci. USA 56 (1966) 236–242. [DOI] [PMID: 5229850]

[EC 1.3.8.4 created 1978 as EC 1.3.99.10, modified 1986, transferred 2012 to EC 1.3.8.4]

1.3.99.10

Transferred entry:

isovaleryl-CoA dehydrogenase. Now EC 1.3.8.4, isovaleryl-CoA dehydrogenase

[EC 1.3.99.10 created 1978, modified 1986, deleted 2012]

1.3.99.21

Transferred entry:

(R)-benzylsuccinyl-CoA dehydrogenase. Now EC 1.3.8.3, (R)-benzylsuccinyl-CoA dehydrogenase

[EC 1.3.99.21 created 2003 as EC 1.3.99.21, deleted 2012]

1.3.99.32

Accepted name:

glutaryl-CoA dehydrogenase (acceptor)

Reaction:

glutaryl-CoA + acceptor = (E)-glutaconyl-CoA + reduced acceptor

Glossary:

(E)-glutaconyl-CoA = (2E)-4-carboxybut-2-enoyl-CoA

Other name(s):

GDHDes; nondecarboxylating glutaryl-coenzyme A dehydrogenase; nondecarboxylating glutaconyl-coenzyme A-forming GDH; glutaryl-CoA dehydrogenase (non-decarboxylating)

Systematic name:

glutaryl-CoA:acceptor 2,3-oxidoreductase (non-decarboxylating)

Comments:

The enzyme contains FAD. The anaerobic, sulfate-reducing bacterium Desulfococcus multivorans contains two glutaryl-CoA dehydrogenases: a decarboxylating enzyme (EC 1.3.8.6), and a nondecarboxylating enzyme (this entry). The two enzymes cause different structural changes around the glutaconyl carboxylate group, primarily due to the presence of either a tyrosine or a valine residue, respectively, at the active site.

Links to other databases:

References:

1.	Wischgoll, S., Taubert, M., Peters, F., Jehmlich, N., von Bergen, M. and Boll, M. Decarboxylating and nondecarboxylating glutaryl-coenzyme A dehydrogenases in the aromatic metabolism of obligately anaerobic bacteria. J. Bacteriol. 191 (2009) 4401–4409. [DOI] [PMID: 19395484]
2.	Wischgoll, S., Demmer, U., Warkentin, E., Gunther, R., Boll, M. and Ermler, U. Structural basis for promoting and preventing decarboxylation in glutaryl-coenzyme A dehydrogenases. Biochemistry 49 (2010) 5350–5357. [DOI] [PMID: 20486657]

[EC 1.3.99.32 created 2012, modified 2013]

1.14.13.150

Transferred entry:

α-humulene 10-hydroxylase. Now EC 1.14.14.113, α-humulene 10-hydroxylase.

[EC 1.14.13.150 created 2012, deleted 2018]

1.14.13.151

Transferred entry:

linalool 8-monooxygenase. Now EC 1.14.14.84, linalool 8-monooxygenase

[EC 1.14.13.151 created 1989 as EC 1.14.99.28, transferred 2012 to EC 1.14.13.151, deleted 2018]

1.14.13.152

Transferred entry:

geraniol 8-hydroxylase. Now EC 1.14.14.83, geraniol 8-hydroxylase

[EC 1.14.13.152 created 2012, deleted 2018]

1.14.13.153

Accepted name:

(+)-sabinene 3-hydroxylase

Reaction:

(+)-sabinene + NADPH + H⁺ + O₂ = (+)-cis-sabinol + NADP⁺ + H₂O

For diagram of thujane monoterpenoid biosynthesis, click here

Systematic name:

(+)-sabinene,NADPH:oxygen oxidoreductase (3-hydroxylating)

Comments:

Requires cytochrome P-450. The enzyme has been characterized from Salvia officinalis (sage).

Links to other databases:

References:

1.	Karp, F., Harris, J.L. and Croteau, R. Metabolism of monoterpenes: demonstration of the hydroxylation of (+)-sabinene to (+)-cis-sabinol by an enzyme preparation from sage (Salvia officinalis) leaves. Arch. Biochem. Biophys. 256 (1987) 179–193. [DOI] [PMID: 3111374]

[EC 1.14.13.153 created 2012]

1.14.13.154

Accepted name:

erythromycin 12-hydroxylase

Reaction:

erythromycin D + NADPH + H⁺ + O₂ = erythromycin C + NADP⁺ + H₂O

For diagram of erythromycin biosynthesis, click here

Other name(s):

EryK

Systematic name:

erythromycin-D,NADPH:oxygen oxidoreductase (12-hydroxylating)

Comments:

The enzyme is responsible for the C-12 hydroxylation of the macrolactone ring, one of the last steps in erythromycin biosynthesis. It shows 1200-1900-fold preference for erythromycin D over the alternative substrate erythromycin B [1].

Links to other databases:

References:

1.	Lambalot, R.H., Cane, D.E., Aparicio, J.J. and Katz, L. Overproduction and characterization of the erythromycin C-12 hydroxylase, EryK. Biochemistry 34 (1995) 1858–1866. [PMID: 7849045]
2.	Savino, C., Montemiglio, L.C., Sciara, G., Miele, A.E., Kendrew, S.G., Jemth, P., Gianni, S. and Vallone, B. Investigating the structural plasticity of a cytochrome P450: three-dimensional structures of P450 EryK and binding to its physiological substrate. J. Biol. Chem. 284 (2009) 29170–29179. [DOI] [PMID: 19625248]
3.	Montemiglio, L.C., Gianni, S., Vallone, B. and Savino, C. Azole drugs trap cytochrome P450 EryK in alternative conformational states. Biochemistry 49 (2010) 9199–9206. [DOI] [PMID: 20845962]

[EC 1.14.13.154 created 2012]

1.14.99.28

Transferred entry:

linalool 8-monooxygenase. Now EC 1.14.14.84, linalool 8-monooxygenase

[EC 1.14.99.28 created 1989, deleted 2012]

1.14.99.46

Accepted name:

pyrimidine oxygenase

Reaction:

(1) uracil + FMNH₂ + O₂ + NADH = (Z)-3-ureidoacrylate + H₂O + FMN + NAD⁺ + H⁺ (overall reaction)
(1a) FMNH₂ + O₂ = FMN-N⁵-peroxide
(1b) uracil + FMN-N⁵-peroxide = (Z)-3-ureidoacrylate + FMN-N⁵-oxide
(1c) FMN-N⁵-oxide + NADH = FMN + H₂O + NAD⁺ + H⁺ (spontaneous)
(2) thymine + FMNH₂ + O₂ + NADH = (Z)-2-methylureidoacrylate + H₂O + FMN + NAD⁺ + H⁺ (overall reaction)
(2a) FMNH₂ + O₂ = FMN-N⁵-peroxide
(2b) thymine + FMN-N⁵-peroxide = (Z)-2-methylureidoacrylate + FMN-N⁵-oxide
(2c) FMN-N⁵-oxide + NADH = FMN + H₂O + NAD⁺ + H⁺ (spontaneous)

For diagram of pyrimidine catabolism, click here

Glossary:

(Z)-3-ureidoacrylate = (2Z)-3-(carbamoylamino)prop-2-enoate
(Z)-2-methylureidoacrylate = (2Z)-3-(carbamoylamino)-2-methylprop-2-enoate

Other name(s):

rutA (gene name)

Systematic name:

uracil,FMNH₂:oxygen oxidoreductase (uracil hydroxylating, ring-opening)

Comments:

The enzyme participates in the Rut pyrimidine catabolic pathway. The flavin-N⁵-oxide that is formed by the enzyme reacts spontaneously with NADH to give oxidized flavin, releasing a water molecule.

Links to other databases:

References:

1.	Mukherjee, T., Zhang, Y., Abdelwahed, S., Ealick, S.E. and Begley, T.P. Catalysis of a flavoenzyme-mediated amide hydrolysis. J. Am. Chem. Soc. 132 (2010) 5550–5551. [DOI] [PMID: 20369853]
2.	Kim, K.S., Pelton, J.G., Inwood, W.B., Andersen, U., Kustu, S. and Wemmer, D.E. The Rut pathway for pyrimidine degradation: novel chemistry and toxicity problems. J. Bacteriol. 192 (2010) 4089–4102. [DOI] [PMID: 20400551]
3.	Adak, S. and Begley, T.P. RutA-catalyzed oxidative cleavage of the uracil amide involves formation of a flavin-N⁵-oxide. Biochemistry 56 (2017) 3708–3709. [PMID: 28661684]
4.	Adak, S. and Begley, T.P. Flavin-N⁵-oxide: A new, catalytic motif in flavoenzymology. Arch. Biochem. Biophys. 632 (2017) 4–10. [PMID: 28784589]
5.	Matthews, A., Saleem-Batcha, R., Sanders, J.N., Stull, F., Houk, K.N. and Teufel, R. Aminoperoxide adducts expand the catalytic repertoire of flavin monooxygenases. Nat. Chem. Biol. 16 (2020) 556–563. [DOI] [PMID: 32066967]

[EC 1.14.99.46 created 2012, modified 2019]

1.17.2.2

Accepted name:

lupanine 17-hydroxylase (cytochrome c)

Reaction:

lupanine + 2 ferricytochrome c + H₂O = 17-hydroxylupanine + 2 ferrocytochrome c + 2 H⁺

Other name(s):

lupanine dehydrogenase (cytochrome c)

Systematic name:

lupanine:cytochrome c-oxidoreductase (17-hydroxylating)

Comments:

The enzyme isolated from Pseudomonas putida contains heme c and requires pyrroloquinoline quinone (PQQ) for activity

Links to other databases:

References:

1.	Hopper, D.J., Rogozinski, J. and Toczko, M. Lupanine hydroxylase, a quinocytochrome c from an alkaloid-degrading Pseudomonas sp. Biochem. J. 279 (1991) 105–109. [PMID: 1656935]
2.	Hopper, D.J. and Kaderbhai, M.A. The quinohaemoprotein lupanine hydroxylase from Pseudomonas putida. Biochim. Biophys. Acta 1647 (2003) 110–115. [DOI] [PMID: 12686118]

[EC 1.17.2.2 created 2012]

*EC

2.1.1.90

Accepted name:

methanol—corrinoid protein Co-methyltransferase

Reaction:

methanol + a [Co(I) methanol-specific corrinoid protein] = a [methyl-Co(III) methanol-specific corrinoid protein] + H₂O

Other name(s):

methanol cobalamin methyltransferase; methanol:5-hydroxybenzimidazolylcobamide methyltransferase; MT 1 (ambiguous); methanol—5-hydroxybenzimidazolylcobamide Co-methyltransferase; mtaB (gene name)

Systematic name:

methanol:5-hydroxybenzimidazolylcobamide Co-methyltransferase

Comments:

The enzyme, which catalyses the transfer of methyl groups from methanol to a methanol-specific corrinoid protein (MtaC), is involved in methanogenesis from methanol. Methylation of the corrinoid protein requires the central cobalt to be in the Co(I) state. During methylation the cobalt is oxidized to the Co(III) state. Free cob(I)alamin can substitute for the corrinoid protein in vitro [2]. Inactivated by oxygen and other oxidizing agents, and reactivated by catalytic amounts of ATP and hydrogen.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, PDB, CAS registry number: 86611-98-5

References:

1.	van der Meijden, P., te Brömmelstroet, B.W., Poirot, C.M., van der Drift, C. and Vogels, G.D. Purification and properties of methanol:5-hydroxybenzimidazolylcobamide methyltransferase from Methanosarcina barkeri. J. Bacteriol. 160 (1984) 629–635. [PMID: 6438059]
2.	Sauer, K. and Thauer, R.K. Methanol:coenzyme M methyltransferase from Methanosarcina barkeri – substitution of the corrinoid harbouring subunit MtaC by free cob(I)alamin. Eur. J. Biochem. 261 (1999) 674–681. [DOI] [PMID: 10215883]

[EC 2.1.1.90 created 1989, modified 2012]

2.1.1.243

Accepted name:

5-guanidino-2-oxopentanoate (3R)-methyltransferase

Reaction:

S-adenosyl-L-methionine + 5-guanidino-2-oxopentanoate = S-adenosyl-L-homocysteine + (3R)-5-guanidino-3-methyl-2-oxopentanoate

Glossary:

5-guanidino-2-oxopentanoate = 2-ketoarginine
(3R)-5-guanidino-3-methyl-2-oxopentanoate = (3R)-5-carbamimidamido-3-methyl-2-oxopentanoate

Other name(s):

mrsA (gene name); argN (gene name); 2-ketoarginine methyltransferase; S-adenosyl-L-methionine:5-carbamimidamido-2-oxopentanoate S-methyltransferase

Systematic name:

S-adenosyl-L-methionine:5-guanidino-2-oxopentanoate (3R)-methyltransferase

Comments:

The enzyme is involved in production of the rare amino acid (3R)-3-methyl-L-arginine. The compound is used by the epiphytic bacterium Pseudomonas syringae pv. syringae as an antibiotic against the related pathogenic species Pseudomonas savastanoi pv. glycinea. Other bacteria incorporate the compound into more complex compounds such as the peptidyl nucleoside antibiotic arginomycin.

Links to other databases:

References:

1.	Braun, S.D., Hofmann, J., Wensing, A., Ullrich, M.S., Weingart, H., Völksch, B. and Spiteller, D. Identification of the biosynthetic gene cluster for 3-methylarginine, a toxin produced by Pseudomonas syringae pv. syringae 22d/93. Appl. Environ. Microbiol. 76 (2010) 2500–2508. [DOI] [PMID: 20190091]
2.	Feng, J., Wu, J., Gao, J., Xia, Z., Deng, Z. and He, X. Biosynthesis of the β-methylarginine residue of peptidyl nucleoside arginomycin in Streptomyces arginensis NRRL 15941. Appl. Environ. Microbiol. 80 (2014) 5021–5027. [DOI] [PMID: 24907335]

[EC 2.1.1.243 created 2012, modified 2024]

2.1.1.244

Accepted name:

protein N-terminal methyltransferase

Reaction:

(1) 3 S-adenosyl-L-methionine + N-terminal-(A,S)PK-[protein] = 3 S-adenosyl-L-homocysteine + N-terminal-N,N,N-trimethyl-N-(A,S)PK-[protein] (overall reaction)
(1a) S-adenosyl-L-methionine + N-terminal-(A,S)PK-[protein] = S-adenosyl-L-homocysteine + N-terminal-N-methyl-N-(A,S)PK-[protein]
(1b) S-adenosyl-L-methionine + N-terminal-N-methyl-N-(A,S)PK-[protein] = S-adenosyl-L-homocysteine + N-terminal-N,N-dimethyl-N-(A,S)PK-[protein]
(1c) S-adenosyl-L-methionine + N-terminal-N,N-dimethyl-N-(A,S)PK-serine-[protein] = S-adenosyl-L-homocysteine + N-terminal-N,N,N-trimethyl-N-(A,S)PK-[protein]
(2) 2 S-adenosyl-L-methionine + N-terminal-PPK-[protein] = 2 S-adenosyl-L-homocysteine + N-terminal-N,N-dimethyl-N-PPK-[protein] (overall reaction)
(2a) S-adenosyl-L-methionine + N-terminal-PPK-[protein] = S-adenosyl-L-homocysteine + N-terminal-N-methyl-N-PPK-[protein]
(2b) S-adenosyl-L-methionine + N-terminal-N-methyl-N-PPK-[protein] = S-adenosyl-L-homocysteine + N-terminal-N,N-dimethyl-N-PPK-[protein]

Other name(s):

NMT1 (gene name); METTL11A (gene name)

Systematic name:

S-adenosyl-L-methionine:N-terminal-(A,P,S)PK-[protein] methyltransferase

Comments:

This enzyme methylates the N-terminus of target proteins containing the N-terminal motif [Ala/Pro/Ser]-Pro-Lys after the initiator L-methionine is cleaved. When the terminal amino acid is L-proline, the enzyme catalyses two successive methylations of its α-amino group. When the first amino acid is either L-alanine or L-serine, the enzyme catalyses three successive methylations. The Pro-Lys in positions 2-3 cannot be exchanged for other amino acids [1,2].

Links to other databases:

References:

1.	Webb, K.J., Lipson, R.S., Al-Hadid, Q., Whitelegge, J.P. and Clarke, S.G. Identification of protein N-terminal methyltransferases in yeast and humans. Biochemistry 49 (2010) 5225–5235. [DOI] [PMID: 20481588]
2.	Tooley, C.E., Petkowski, J.J., Muratore-Schroeder, T.L., Balsbaugh, J.L., Shabanowitz, J., Sabat, M., Minor, W., Hunt, D.F. and Macara, I.G. NRMT is an α-N-methyltransferase that methylates RCC1 and retinoblastoma protein. Nature 466 (2010) 1125–1128. [DOI] [PMID: 20668449]

[EC 2.1.1.244 created 2012]

2.1.1.245

Accepted name:

5-methyltetrahydrosarcinapterin—corrinoid/iron-sulfur protein Co-methyltransferase

Reaction:

a [methyl-Co(III) corrinoid Fe-S protein] + tetrahydrosarcinapterin = a [Co(I) corrinoid Fe-S protein] + 5-methyltetrahydrosarcinapterin

Other name(s):

cdhD (gene name); cdhE (gene name)

Systematic name:

5-methyltetrahydrosarcinapterin:corrinoid/iron-sulfur protein methyltransferase

Comments:

Catalyses the transfer of a methyl group from the cobamide cofactor of a corrinoid/Fe-S protein to the N⁵ group of tetrahydrosarcinapterin. Forms, together with EC 1.2.7.4, anaerobic carbon-monoxide dehydrogenase, and EC 2.3.1.169, CO-methylating acetyl-CoA synthase, the acetyl-CoA decarbonylase/synthase complex that catalyses the demethylation of acetyl-CoA in a reaction that also forms CO2. This reaction is a key step in methanogenesis from acetate.

Links to other databases:

References:

1.	Maupin-Furlow, J. and Ferry, J.G. Characterization of the cdhD and cdhE genes encoding subunits of the corrinoid/iron-sulfur enzyme of the CO dehydrogenase complex from Methanosarcina thermophila. J. Bacteriol. 178 (1996) 340–346. [DOI] [PMID: 8550451]
2.	Grahame, D.A. and DeMoll, E. Partial reactions catalyzed by protein components of the acetyl-CoA decarbonylase synthase enzyme complex from Methanosarcina barkeri. J. Biol. Chem. 271 (1996) 8352–8358. [DOI] [PMID: 8626532]

[EC 2.1.1.245 created 2012]

2.1.1.246

Accepted name:

[methyl-Co(III) methanol-specific corrinoid protein]—coenzyme M methyltransferase

Reaction:

a [methyl-Co(III) methanol-specific corrinoid protein] + CoM = methyl-CoM + a [Co(I) methanol-specific corrinoid protein]

Glossary:

CoM = coenzyme M = 2-sulfanylethane-1-sulfonate = 2-mercaptoethanesulfonate (deprecated)

Other name(s):

methyltransferase 2 (ambiguous); mtaA (gene name)

Systematic name:

methylated methanol-specific corrinoid protein:CoM methyltransferase

Comments:

The enzyme, which is involved in methanogenesis from methanol, catalyses the transfer of a methyl group from a corrinoid protein (see EC 2.1.1.90, methanol—corrinoid protein Co-methyltransferase), where it is bound to the cobalt cofactor, to CoM, forming the substrate for EC 2.8.4.1, coenzyme-B sulfoethylthiotransferase, the enzyme that catalyses the final step in methanogenesis. Free methylcob(I)alamin can substitute for the corrinoid protein in vitro [5].

Links to other databases:

References:

1.	LeClerc, G.M. and Grahame, D.A. Methylcobamide:coenzyme M methyltransferase isozymes from Methanosarcina barkeri. Physicochemical characterization, cloning, sequence analysis, and heterologous gene expression. J. Biol. Chem. 271 (1996) 18725–18731. [DOI] [PMID: 8702528]
2.	Harms, U. and Thauer, R.K. Methylcobalamin: coenzyme M methyltransferase isoenzymes MtaA and MtbA from Methanosarcina barkeri. Cloning, sequencing and differential transcription of the encoding genes, and functional overexpression of the mtaA gene in Escherichia coli. Eur. J. Biochem. 235 (1996) 653–659. [DOI] [PMID: 8654414]
3.	Sauer, K. and Thauer, R.K. Methanol:coenzyme M methyltransferase from Methanosarcina barkeri. Zinc dependence and thermodynamics of the methanol:cob(I)alamin methyltransferase reaction. Eur. J. Biochem. 249 (1997) 280–285. [DOI] [PMID: 9363780]
4.	Sauer, K., Harms, U. and Thauer, R.K. Methanol:coenzyme M methyltransferase from Methanosarcina barkeri. Purification, properties and encoding genes of the corrinoid protein MT1. Eur. J. Biochem. 243 (1997) 670–677. [DOI] [PMID: 9057830]
5.	Sauer, K. and Thauer, R.K. Methanol:coenzyme M methyltransferase from Methanosarcina barkeri – substitution of the corrinoid harbouring subunit MtaC by free cob(I)alamin. Eur. J. Biochem. 261 (1999) 674–681. [DOI] [PMID: 10215883]

[EC 2.1.1.246 created 2012]

2.1.1.247

Accepted name:

[methyl-Co(III) methylamine-specific corrinoid protein]—coenzyme M methyltransferase

Reaction:

a [methyl-Co(III) methylamine-specific corrinoid protein] + CoM = methyl-CoM + a [Co(I) methylamine-specific corrinoid protein]

Glossary:

CoM = coenzyme M = 2-sulfanylethane-1-sulfonate = 2-mercaptoethanesulfonate (deprecated)

Other name(s):

methyltransferase 2 (ambiguous); MT2 (ambiguous); MT2-A; mtbA (gene name); [methyl-Co(III) methylamine-specific corrinoid protein]:coenzyme M methyltransferase

Systematic name:

methylated monomethylamine-specific corrinoid protein:CoM methyltransferase

Comments:

Contains zinc [2]. The enzyme, which is involved in methanogenesis from mono-, di-, and trimethylamine, catalyses the transfer of a methyl group bound to the cobalt cofactor of several corrinoid proteins (mono-, di-, and trimethylamine-specific corrinoid proteins, cf. EC 2.1.1.248, methylamine—corrinoid protein Co-methyltransferase, EC 2.1.1.249, dimethylamine—corrinoid protein Co-methyltransferase, and EC 2.1.1.250, trimethylamine—corrinoid protein Co-methyltransferase) to CoM, forming the substrate for EC 2.8.4.1, coenzyme-B sulfoethylthiotransferase, the enzyme that catalyses the final step in methanogenesis.

Links to other databases:

References:

1.	Burke, S.A. and Krzycki, J.A. Involvement of the "A" isozyme of methyltransferase II and the 29-kilodalton corrinoid protein in methanogenesis from monomethylamine. J. Bacteriol. 177 (1995) 4410–4416. [DOI] [PMID: 7635826]
2.	LeClerc, G.M. and Grahame, D.A. Methylcobamide:coenzyme M methyltransferase isozymes from Methanosarcina barkeri. Physicochemical characterization, cloning, sequence analysis, and heterologous gene expression. J. Biol. Chem. 271 (1996) 18725–18731. [DOI] [PMID: 8702528]
3.	Ferguson, D.J., Jr. and Krzycki, J.A. Reconstitution of trimethylamine-dependent coenzyme M methylation with the trimethylamine corrinoid protein and the isozymes of methyltransferase II from Methanosarcina barkeri. J. Bacteriol. 179 (1997) 846–852. [DOI] [PMID: 9006042]
4.	Burke, S.A., Lo, S.L. and Krzycki, J.A. Clustered genes encoding the methyltransferases of methanogenesis from monomethylamine. J. Bacteriol. 180 (1998) 3432–3440. [PMID: 9642198]
5.	Ferguson, D.J., Jr., Gorlatova, N., Grahame, D.A. and Krzycki, J.A. Reconstitution of dimethylamine:coenzyme M methyl transfer with a discrete corrinoid protein and two methyltransferases purified from Methanosarcina barkeri. J. Biol. Chem. 275 (2000) 29053–29060. [DOI] [PMID: 10852929]

[EC 2.1.1.247 created 2012]

2.1.1.248

Accepted name:

methylamine—corrinoid protein Co-methyltransferase

Reaction:

methylamine + a [Co(I) methylamine-specific corrinoid protein] = a [methyl-Co(III) methylamine-specific corrinoid protein] + NH₃

Other name(s):

mtmB (gene name); monomethylamine methyltransferase

Systematic name:

monomethylamine:5-hydroxybenzimidazolylcobamide Co-methyltransferase

Comments:

The enzyme, which catalyses the transfer of a methyl group from methylamine to a methylamine-specific corrinoid protein (MtmC), is involved in methanogenesis from methylamine. The enzyme contains the unusual amino acid pyrrolysine [3]. Methylation of the corrinoid protein requires the central cobalt to be in the Co(I) state. During methylation the cobalt is oxidized to the Co(III) state. The methylated corrinoid protein is substrate for EC 2.1.1.247, methylated methylamine-specific corrinoid protein:coenzyme M methyltransferase.

Links to other databases:

References:

1.	Burke, S.A. and Krzycki, J.A. Reconstitution of Monomethylamine:Coenzyme M methyl transfer with a corrinoid protein and two methyltransferases purified from Methanosarcina barkeri. J. Biol. Chem. 272 (1997) 16570–16577. [DOI] [PMID: 9195968]
2.	Burke, S.A., Lo, S.L. and Krzycki, J.A. Clustered genes encoding the methyltransferases of methanogenesis from monomethylamine. J. Bacteriol. 180 (1998) 3432–3440. [PMID: 9642198]
3.	Krzycki, J.A. Function of genetically encoded pyrrolysine in corrinoid-dependent methylamine methyltransferases. Curr. Opin. Chem. Biol. 8 (2004) 484–491. [DOI] [PMID: 15450490]

[EC 2.1.1.248 created 2012]

2.1.1.249

Accepted name:

dimethylamine—corrinoid protein Co-methyltransferase

Reaction:

dimethylamine + a [Co(I) dimethylamine-specific corrinoid protein] = a [methyl-Co(III) dimethylamine-specific corrinoid protein] + methylamine

Other name(s):

mtbB (gene name); dimethylamine methyltransferase

Systematic name:

dimethylamine:5-hydroxybenzimidazolylcobamide Co-methyltransferase

Comments:

The enzyme, which catalyses the transfer of a methyl group from dimethylamine to a dimethylamine-specific corrinoid protein (MtbC), is involved in methanogenesis from dimethylamine. The enzyme contains the unusual amino acid pyrrolysine [3]. Methylation of the corrinoid protein requires the central cobalt to be in the Co(I) state. During methylation the cobalt is oxidized to the Co(III) state. The methylated corrinoid protein is substrate for EC 2.1.1.247, methylated methylamine-specific corrinoid protein:coenzyme M methyltransferase.

Links to other databases:

References:

1.	Wassenaar, R.W., Keltjens, J.T., van der Drift, C. and Vogels, G.D. Purification and characterization of dimethylamine:5-hydroxybenzimidazolyl-cobamide methyltransferase from Methanosarcina barkeri Fusaro. Eur. J. Biochem. 253 (1998) 692–697. [DOI] [PMID: 9654067]
2.	Ferguson, D.J., Jr., Gorlatova, N., Grahame, D.A. and Krzycki, J.A. Reconstitution of dimethylamine:coenzyme M methyl transfer with a discrete corrinoid protein and two methyltransferases purified from Methanosarcina barkeri. J. Biol. Chem. 275 (2000) 29053–29060. [DOI] [PMID: 10852929]
3.	Krzycki, J.A. Function of genetically encoded pyrrolysine in corrinoid-dependent methylamine methyltransferases. Curr. Opin. Chem. Biol. 8 (2004) 484–491. [DOI] [PMID: 15450490]

[EC 2.1.1.249 created 2012]

2.1.1.250

Accepted name:

trimethylamine—corrinoid protein Co-methyltransferase

Reaction:

trimethylamine + a [Co(I) trimethylamine-specific corrinoid protein] = a [methyl-Co(III) trimethylamine-specific corrinoid protein] + dimethylamine

Other name(s):

mttB (gene name); trimethylamine methyltransferase

Systematic name:

trimethylamine:5-hydroxybenzimidazolylcobamide Co-methyltransferase

Comments:

The enzyme, which catalyses the transfer of a methyl group from trimethylamine to a trimethylamine-specific corrinoid protein (MttC), is involved in methanogenesis from trimethylamine. The enzyme contains the unusual amino acid pyrrolysine [2]. Methylation of the corrinoid protein requires the central cobalt to be in the Co(I) state. During methylation the cobalt is oxidized to the Co(III) state. The methylated corrinoid protein is substrate for EC 2.1.1.247, methylated methylamine-specific corrinoid protein:coenzyme M methyltransferase.

Links to other databases:

References:

1.	Ferguson, D.J., Jr. and Krzycki, J.A. Reconstitution of trimethylamine-dependent coenzyme M methylation with the trimethylamine corrinoid protein and the isozymes of methyltransferase II from Methanosarcina barkeri. J. Bacteriol. 179 (1997) 846–852. [DOI] [PMID: 9006042]
2.	Krzycki, J.A. Function of genetically encoded pyrrolysine in corrinoid-dependent methylamine methyltransferases. Curr. Opin. Chem. Biol. 8 (2004) 484–491. [DOI] [PMID: 15450490]

[EC 2.1.1.250 created 2012]

2.1.1.251

Accepted name:

methylated-thiol—coenzyme M methyltransferase

Reaction:

methanethiol + CoM = methyl-CoM + hydrogen sulfide (overall reaction)
(1a) methanethiol + a [Co(I) methylated-thiol-specific corrinoid protein] = a [methyl-Co(III) methylated-thiol-specific corrinoid protein] + hydrogen sulfide
(1b) a [methyl-Co(III) methylated-thiol-specific corrinoid protein] + CoM = methyl-CoM + a [Co(I) methylated-thiol-specific corrinoid protein]

Glossary:

CoM = coenzyme M = 2-sulfanylethane-1-sulfonate = 2-mercaptoethanesulfonate (deprecated)

Other name(s):

mtsA (gene name)

Systematic name:

methylated-thiol:CoM methyltransferase

Comments:

The enzyme, which is involved in methanogenesis from methylated thiols, such as methane thiol, dimethyl sulfide, and 3-(methylsulfanyl)propanoate, catalyses two successive steps - the transfer of a methyl group from the substrate to the cobalt cofactor of a methylated-thiol-specific corrinoid protein (MtsB), and the subsequent transfer of the methyl group from the corrinoid protein to CoM. With most other methanogenesis substrates this process is carried out by two different enzymes (for example, EC 2.1.1.90, methanol—corrinoid protein Co-methyltransferase, and EC 2.1.1.246, [methyl-Co(III) methanol-specific corrinoid protein]—coenzyme M methyltransferase). The cobalt is oxidized during methylation from the Co(I) state to the Co(III) state, and is reduced back to the Co(I) form during demethylation.

Links to other databases:

References:

1.	Paul, L. and Krzycki, J.A. Sequence and transcript analysis of a novel Methanosarcina barkeri methyltransferase II homolog and its associated corrinoid protein homologous to methionine synthase. J. Bacteriol. 178 (1996) 6599–6607. [DOI] [PMID: 8932317]
2.	Tallant, T.C. and Krzycki, J.A. Methylthiol:coenzyme M methyltransferase from Methanosarcina barkeri, an enzyme of methanogenesis from dimethylsulfide and methylmercaptopropionate. J. Bacteriol. 179 (1997) 6902–6911. [DOI] [PMID: 9371433]
3.	Tallant, T.C., Paul, L. and Krzycki, J.A. The MtsA subunit of the methylthiol:coenzyme M methyltransferase of Methanosarcina barkeri catalyses both half-reactions of corrinoid-dependent dimethylsulfide: coenzyme M methyl transfer. J. Biol. Chem. 276 (2001) 4485–4493. [DOI] [PMID: 11073950]

[EC 2.1.1.251 created 2012]

2.1.1.252

Accepted name:

tetramethylammonium—corrinoid protein Co-methyltransferase

Reaction:

tetramethylammonium + a [Co(I) tetramethylammonium-specific corrinoid protein] = a [methyl-Co(III) tetramethylammonium-specific corrinoid protein] + trimethylamine

Other name(s):

mtqB (gene name); tetramethylammonium methyltransferase

Systematic name:

tetramethylammonium:5-hydroxybenzimidazolylcobamide Co-methyltransferase

Comments:

The enzyme, which catalyses the transfer of a methyl group from tetramethylammonium to a tetramethylammonium-specific corrinoid protein (MtqC), is involved in methanogenesis from tetramethylammonium. Methylation of the corrinoid protein requires the central cobalt to be in the Co(I) state. During methylation the cobalt is oxidized to the Co(III) state. The methylated corrinoid protein is substrate for EC 2.1.1.253, methylated tetramethylammonium-specific corrinoid protein:coenzyme M methyltransferase.

Links to other databases:

References:

1.	Asakawa, S., Sauer, K., Liesack, W. and Thauer, R.K. Tetramethylammonium:coenzyme M methyltransferase system from methanococcoides s. Arch. Microbiol. 170 (1998) 220–226. [PMID: 9732435]

[EC 2.1.1.252 created 2012]

2.1.1.253

Accepted name:

[methyl-Co(III) tetramethylammonium-specific corrinoid protein]—coenzyme M methyltransferase

Reaction:

a [methyl-Co(III) tetramethylammonium-specific corrinoid protein] + CoM = methyl-CoM + a [Co(I) tetramethylammonium-specific corrinoid protein]

Glossary:

CoM = coenzyme M = 2-sulfanylethane-1-sulfonate = 2-mercaptoethanesulfonate (deprecated)

Other name(s):

methyltransferase 2 (ambiguous); mtqA (gene name)

Systematic name:

methylated tetramethylammonium-specific corrinoid protein:CoM methyltransferase

Comments:

The enzyme, which is involved in methanogenesis from tetramethylammonium, catalyses the transfer of a methyl group from a corrinoid protein (see EC 2.1.1.252, tetramethylammonium—corrinoid protein Co-methyltransferase), where it is bound to the cobalt cofactor, to CoM, forming the substrate for EC 2.8.4.1, coenzyme-B sulfoethylthiotransferase, the enzyme that catalyses the final step in methanogenesis.

Links to other databases:

References:

1.	Asakawa, S., Sauer, K., Liesack, W. and Thauer, R.K. Tetramethylammonium:coenzyme M methyltransferase system from methanococcoides s. Arch. Microbiol. 170 (1998) 220–226. [PMID: 9732435]

[EC 2.1.1.253 created 2012]

2.1.1.254

Accepted name:

erythromycin 3′′-O-methyltransferase

Reaction:

(1) S-adenosyl-L-methionine + erythromycin C = S-adenosyl-L-homocysteine + erythromycin A
(2) S-adenosyl-L-methionine + erythromycin D = S-adenosyl-L-homocysteine + erythromycin B

For diagram of erythromycin biosynthesis, click here

Other name(s):

EryG

Systematic name:

S-adenosyl-L-methionine:erythromycin C 3′′-O-methyltransferase

Comments:

The enzyme methylates the 3 position of the mycarosyl moiety of erythromycin C, forming the most active form of the antibiotic, erythromycin A. It can also methylate the precursor erythromycin D, forming erythromycin B, which is then converted to erythromycin A by EC 1.14.13.154, erythromycin 12 hydroxylase.

Links to other databases:

References:

1.	Paulus, T.J., Tuan, J.S., Luebke, V.E., Maine, G.T., DeWitt, J.P. and Katz, L. Mutation and cloning of eryG, the structural gene for erythromycin O-methyltransferase from Saccharopolyspora erythraea, and expression of eryG in Escherichia coli. J. Bacteriol. 172 (1990) 2541–2546. [DOI] [PMID: 2185226]
2.	Summers, R.G., Donadio, S., Staver, M.J., Wendt-Pienkowski, E., Hutchinson, C.R. and Katz, L. Sequencing and mutagenesis of genes from the erythromycin biosynthetic gene cluster of Saccharopolyspora erythraea that are involved in L-mycarose and D-desosamine production. Microbiology 143 (1997) 3251–3262. [DOI] [PMID: 9353926]

[EC 2.1.1.254 created 2012]

2.1.1.255

Accepted name:

geranyl diphosphate 2-C-methyltransferase

Reaction:

S-adenosyl-L-methionine + geranyl diphosphate = S-adenosyl-L-homocysteine + (E)-2-methylgeranyl diphosphate

For diagram of reaction, click here

Other name(s):

SCO7701; GPP methyltransferase; GPPMT; 2-methyl-GPP synthase; MGPPS; geranyl pyrophosphate methyltransferase

Systematic name:

S-adenosyl-L-methionine:geranyl-diphosphate 2-C-methyltransferase

Comments:

This enzyme, along with EC 4.2.3.118, 2-methylisoborneol synthase, produces 2-methylisoborneol, an odiferous compound produced by soil microorganisms with a strong earthy/musty odour.

Links to other databases:

References:

1.	Wang, C.M. and Cane, D.E. Biochemistry and molecular genetics of the biosynthesis of the earthy odorant methylisoborneol in Streptomyces coelicolor. J. Am. Chem. Soc. 130 (2008) 8908–8909. [DOI] [PMID: 18563898]
2.	Ariyawutthiphan, O., Ose, T., Tsuda, M., Gao, Y., Yao, M., Minami, A., Oikawa, H. and Tanaka, I. Crystallization and preliminary X-ray crystallographic study of a methyltransferase involved in 2-methylisoborneol biosynthesis in Streptomyces lasaliensis. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 67 (2011) 417–420. [DOI] [PMID: 21393856]
3.	Komatsu, M., Tsuda, M., Omura, S., Oikawa, H. and Ikeda, H. Identification and functional analysis of genes controlling biosynthesis of 2-methylisoborneol. Proc. Natl. Acad. Sci. USA 105 (2008) 7422–7427. [DOI] [PMID: 18492804]
4.	Giglio, S., Chou, W.K., Ikeda, H., Cane, D.E. and Monis, P.T. Biosynthesis of 2-methylisoborneol in cyanobacteria. Environ. Sci. Technol. 45 (2011) 992–998. [DOI] [PMID: 21174459]

[EC 2.1.1.255 created 2012]

2.4.1.279

Accepted name:

nigerose phosphorylase

Reaction:

3-O-α-D-glucopyranosyl-D-glucopyranose + phosphate = D-glucose + β-D-glucose 1-phosphate

Glossary:

3-O-α-D-glucopyranosyl-D-glucopyranose = nigerose

Other name(s):

cphy1874 (gene name)

Systematic name:

3-O-α-D-glucopyranosyl-D-glucopyranose:phosphate β-D-glucosyltransferase

Comments:

The enzymes from Clostridium phytofermentans is specific for nigerose, and shows only 0.5% relative activity with kojibiose (cf. EC 2.4.1.230, kojibiose phosphorylase).

Links to other databases:

References:

1.	Nihira, T., Nakai, H., Chiku, K. and Kitaoka, M. Discovery of nigerose phosphorylase from Clostridium phytofermentans. Appl. Microbiol. Biotechnol. 93 (2012) 1513–1522. [DOI] [PMID: 21808968]

[EC 2.4.1.279 created 2012]

2.4.1.280

Accepted name:

N,N′-diacetylchitobiose phosphorylase

Reaction:

N,N′-diacetylchitobiose + phosphate = N-acetyl-D-glucosamine + N-acetyl-α-D-glucosamine 1-phosphate

Glossary:

N,N′-diacetylchitobiose = N-acetyl-D-glucosaminyl-β-(1→4)-N-acetyl-D-glucosamine

Other name(s):

chbP (gene name)

Systematic name:

N,N′-diacetylchitobiose:phosphate N-acetyl-D-glucosaminyltransferase

Comments:

The enzyme is specific for N,N′-diacetylchitobiose and does not phosphorylate other N-acetylchitooligosaccharides, cellobiose, trehalose, lactose, maltose or sucrose.

Links to other databases:

References:

1.	Park, J.K., Keyhani, N.O. and Roseman, S. Chitin catabolism in the marine bacterium Vibrio furnissii. Identification, molecular cloning, and characterization of a N,N′-diacetylchitobiose phosphorylase. J. Biol. Chem. 275 (2000) 33077–33083. [DOI] [PMID: 10913116]
2.	Honda, Y., Kitaoka, M. and Hayashi, K. Reaction mechanism of chitobiose phosphorylase from Vibrio proteolyticus: identification of family 36 glycosyltransferase in Vibrio. Biochem. J. 377 (2004) 225–232. [DOI] [PMID: 13678418]
3.	Hidaka, M., Honda, Y., Kitaoka, M., Nirasawa, S., Hayashi, K., Wakagi, T., Shoun, H. and Fushinobu, S. Chitobiose phosphorylase from Vibrio proteolyticus, a member of glycosyl transferase family 36, has a clan GH-L-like (α/α)₆ barrel fold. Structure 12 (2004) 937–947. [DOI] [PMID: 15274915]

[EC 2.4.1.280 created 2012]

2.4.1.281

Accepted name:

4-O-β-D-mannosyl-D-glucose phosphorylase

Reaction:

4-O-β-D-mannopyranosyl-D-glucopyranose + phosphate = D-glucose + α-D-mannose 1-phosphate

Glossary:

4-O-β-D-mannopyranosyl-D-glucopyranose = β-D-mannopyranosyl-(1→4)-D-glucopyranose

Other name(s):

mannosylglucose phosphorylase

Systematic name:

4-O-β-D-mannopyranosyl-D-glucopyranose:phosphate α-D-mannosyltransferase

Comments:

This enzyme forms part of a mannan catabolic pathway in the anaerobic bacterium Bacteroides fragilis NCTC 9343.

Links to other databases:

References:

1.	Senoura, T., Ito, S., Taguchi, H., Higa, M., Hamada, S., Matsui, H., Ozawa, T., Jin, S., Watanabe, J., Wasaki, J. and Ito, S. New microbial mannan catabolic pathway that involves a novel mannosylglucose phosphorylase. Biochem. Biophys. Res. Commun. 408 (2011) 701–706. [DOI] [PMID: 21539815]

[EC 2.4.1.281 created 2012]

2.4.99.16

Accepted name:

starch synthase (maltosyl-transferring)

Reaction:

α-maltose 1-phosphate + [(1→4)-α-D-glucosyl]_n = phosphate + [(1→4)-α-D-glucosyl]_n+2

Other name(s):

α1,4-glucan:maltose-1-P maltosyltransferase; GMPMT

Systematic name:

α-maltose 1-phosphate:(1→4)-α-D-glucan 4-α-D-maltosyltransferase

Comments:

The enzyme from the bacterium Mycobacterium smegmatis is specific for maltose. It has no activity with α-D-glucose.

Links to other databases:

References:

1.	Elbein, A.D., Pastuszak, I., Tackett, A.J., Wilson, T. and Pan, Y.T. Last step in the conversion of trehalose to glycogen: a mycobacterial enzyme that transfers maltose from maltose 1-phosphate to glycogen. J. Biol. Chem. 285 (2010) 9803–9812. [DOI] [PMID: 20118231]
2.	Syson, K., Stevenson, C.E., Rejzek, M., Fairhurst, S.A., Nair, A., Bruton, C.J., Field, R.A., Chater, K.F., Lawson, D.M. and Bornemann, S. Structure of Streptomyces maltosyltransferase GlgE, a homologue of a genetically validated anti-tuberculosis target. J. Biol. Chem. 286 (2011) 38298–38310. [DOI] [PMID: 21914799]

[EC 2.4.99.16 created 2012]

2.7.1.173

Accepted name:

nicotinate riboside kinase

Reaction:

ATP + β-D-ribosylnicotinate = ADP + nicotinate β-D-ribonucleotide

Other name(s):

ribosylnicotinic acid kinase; nicotinic acid riboside kinase; NRK1 (ambiguous)

Systematic name:

ATP:β-D-ribosylnicotinate 5-phosphotransferase

Comments:

The enzyme from yeast and human also has the activity of EC 2.7.1.22 (ribosylnicotinamide kinase).

Links to other databases:

References:

1.	Tempel, W., Rabeh, W.M., Bogan, K.L., Belenky, P., Wojcik, M., Seidle, H.F., Nedyalkova, L., Yang, T., Sauve, A.A., Park, H.W. and Brenner, C. Nicotinamide riboside kinase structures reveal new pathways to NAD⁺. PLoS Biol. 5:e263 (2007). [DOI] [PMID: 17914902]

[EC 2.7.1.173 created 2012]

2.7.1.174

Accepted name:

diacylglycerol kinase (CTP)

Reaction:

CTP + 1,2-diacyl-sn-glycerol = CDP + 1,2-diacyl-sn-glycerol 3-phosphate

Glossary:

1,2-diacyl-sn-glycerol 3-phosphate = phosphatidate

Other name(s):

DAG kinase; CTP-dependent diacylglycerol kinase; diglyceride kinase (ambiguous); DGK1 (gene name); diacylglycerol kinase (CTP dependent)

Systematic name:

CTP:1,2-diacyl-sn-glycerol 3-phosphotransferase

Comments:

Requires Ca²⁺ or Mg²⁺ for activity. Involved in synthesis of membrane phospholipids and the neutral lipid triacylglycerol. Unlike the diacylglycerol kinases from bacteria, plants, and animals [cf. EC 2.7.1.107, diacylglycerol kinase (ATP)], the enzyme from Saccharomyces cerevisiae utilizes CTP. The enzyme can also use dCTP, but not ATP, GTP or UTP.

Links to other databases:

References:

1.	Han, G.S., O'Hara, L., Carman, G.M. and Siniossoglou, S. An unconventional diacylglycerol kinase that regulates phospholipid synthesis and nuclear membrane growth. J. Biol. Chem. 283 (2008) 20433–20442. [DOI] [PMID: 18458075]
2.	Han, G.S., O'Hara, L., Siniossoglou, S. and Carman, G.M. Characterization of the yeast DGK1-encoded CTP-dependent diacylglycerol kinase. J. Biol. Chem. 283 (2008) 20443–20453. [DOI] [PMID: 18458076]
3.	Fakas, S., Konstantinou, C. and Carman, G.M. DGK1-encoded diacylglycerol kinase activity is required for phospholipid synthesis during growth resumption from stationary phase in Saccharomyces cerevisiae. J. Biol. Chem. 286 (2011) 1464–1474. [DOI] [PMID: 21071438]

[EC 2.7.1.174 created 2012, modified 2013]

2.7.1.175

Accepted name:

maltokinase

Reaction:

ATP + maltose = ADP + α-maltose 1-phosphate

Systematic name:

ATP:α-maltose 1-phosphotransferase

Comments:

Requires Mg²⁺ for activity.

Links to other databases:

References:

1.	Mendes, V., Maranha, A., Lamosa, P., da Costa, M.S. and Empadinhas, N. Biochemical characterization of the maltokinase from Mycobacterium bovis BCG. BMC Biochem. 11:21 (2010). [DOI] [PMID: 20507595]

[EC 2.7.1.175 created 2012]

2.7.1.176

Accepted name:

UDP-N-acetylglucosamine kinase

Reaction:

ATP + UDP-N-acetyl-α-D-glucosamine = ADP + UDP-N-acetyl-α-D-glucosamine 3′-phosphate

Other name(s):

UNAG kinase; ζ toxin; toxin PezT; ATP:UDP-N-acetyl-D-glucosamine 3′-phosphotransferase

Systematic name:

ATP:UDP-N-acetyl-α-D-glucosamine 3′-phosphotransferase

Comments:

Toxic component of a toxin-antitoxin (TA) module. The phosphorylation of UDP-N-acetyl-D-glucosamine results in the inhibition of EC 2.5.1.7, UDP-N-acetylglucosamine 1-carboxyvinyltransferase, the first committed step in cell wall synthesis, which is then blocked. The activity of this enzyme is inhibited when the enzyme binds to the cognate ε antitoxin.

Links to other databases:

References:

1.	Khoo, S.K., Loll, B., Chan, W.T., Shoeman, R.L., Ngoo, L., Yeo, C.C. and Meinhart, A. Molecular and structural characterization of the PezAT chromosomal toxin-antitoxin system of the human pathogen Streptococcus pneumoniae. J. Biol. Chem. 282 (2007) 19606–19618. [DOI] [PMID: 17488720]
2.	Mutschler, H., Gebhardt, M., Shoeman, R.L. and Meinhart, A. A novel mechanism of programmed cell death in bacteria by toxin-antitoxin systems corrupts peptidoglycan synthesis. PLoS Biol. 9:e1001033 (2011). [DOI] [PMID: 21445328]

[EC 2.7.1.176 created 2012]

3.1.3.87

Accepted name:

2-hydroxy-3-keto-5-methylthiopentenyl-1-phosphate phosphatase

Reaction:

2-hydroxy-5-(methylsulfanyl)-3-oxopent-1-en-1-yl phosphate + H₂O = 1,2-dihydroxy-5-(methylsulfanyl)pent-1-en-3-one + phosphate

Other name(s):

HK-MTPenyl-1-P phosphatase; MtnX; YkrX; 2-hydroxy-5-(methylthio)-3-oxopent-1-enyl phosphate phosphohydrolase; 2-hydroxy-5-(methylsulfanyl)-3-oxopent-1-enyl phosphate phosphohydrolase

Systematic name:

2-hydroxy-5-(methylsulfanyl)-3-oxopent-1-en-1-yl phosphate phosphohydrolase

Comments:

The enzyme participates in the methionine salvage pathway in Bacillus subtilis [2]. In some species a single bifunctional enzyme, EC 3.1.3.77, acireductone synthase, catalyses both this reaction and EC 5.3.2.5, 2,3-diketo-5-methylthiopentyl-1-phosphate enolase [1].

Links to other databases:

References:

1.	Myers, R.W., Wray, J.W., Fish, S. and Abeles, R.H. Purification and characterization of an enzyme involved in oxidative carbon-carbon bond cleavage reactions in the methionine salvage pathway of Klebsiella pneumoniae. J. Biol. Chem. 268 (1993) 24785–24791. [PMID: 8227039]
2.	Ashida, H., Saito, Y., Kojima, C., Kobayashi, K., Ogasawara, N. and Yokota, A. A functional link between RuBisCO-like protein of Bacillus and photosynthetic RuBisCO. Science 302 (2003) 286–290. [DOI] [PMID: 14551435]

[EC 3.1.3.87 created 2012]

3.1.7.11

Accepted name:

geranyl diphosphate diphosphatase

Reaction:

geranyl diphosphate + H₂O = geraniol + diphosphate

For diagram of acyclic monoterpenoid biosynthesis, click here

Other name(s):

geraniol synthase; geranyl pyrophosphate pyrophosphatase; GES; CtGES

Systematic name:

geranyl-diphosphate diphosphohydrolase

Comments:

Isolated from Ocimum basilicum (basil) and Cinnamomum tenuipile (camphor tree). Requires Mg²⁺ or Mn²⁺. Geraniol is labelled when formed in the presence of [¹⁸O]H₂O. Thus mechanism involves a geranyl cation [1]. Neryl diphosphate is hydrolysed more slowly. May be the same as EC 3.1.7.3 monoterpenyl-diphosphatase.

Links to other databases:

References:

1.	Iijima, Y., Gang, D.R., Fridman, E., Lewinsohn, E. and Pichersky, E. Characterization of geraniol synthase from the peltate glands of sweet basil. Plant Physiol. 134 (2004) 370–379. [DOI] [PMID: 14657409]
2.	Yang, T., Li, J., Wang, H.X. and Zeng, Y. A geraniol-synthase gene from Cinnamomum tenuipilum. Phytochemistry 66 (2005) 285–293. [DOI] [PMID: 15680985]

[EC 3.1.7.11 created 2012]

*EC

3.2.1.28

Accepted name:

α,α-trehalase

Reaction:

α,α-trehalose + H₂O = β-D-glucose + α-D-glucose

Other name(s):

trehalase

Systematic name:

α,α-trehalose glucohydrolase

Comments:

The enzyme is an anomer-inverting glucosidase that catalyses the hydrolysis of the α-glucosidic O-linkage of α,α-trehalose, releasing initially equimolar amounts of α- and β-D-glucose. It is widely distributed in microorganisms, plants, invertebrates and vertebrates.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, PDB, CAS registry number: 9025-52-9

References:

1.	Myrbäck, K. and Örtenblad, B. Trehalose und Hefe. II. Trehalasewirkung von Hefepräparaten. Biochem. Z. 291 (1937) 61–69.
2.	Kalf, G.F. and Rieder, S.V. The preparation and properties of trehalase. J. Biol. Chem. 230 (1958) 691–698. [PMID: 13525386]
3.	Hehre, E.J., Sawai, T., Brewer, C.F., Nakano, M. and Kanda, T. Trehalase: stereocomplementary hydrolytic and glucosyl transfer reactions with α- and β-D-glucosyl fluoride. Biochemistry 21 (1982) 3090–3097. [PMID: 7104311]
4.	Mori, H., Lee, J.H., Okuyama, M., Nishimoto, M., Ohguchi, M., Kim, D., Kimura, A. and Chiba, S. Catalytic reaction mechanism based on α-secondary deuterium isotope effects in hydrolysis of trehalose by European honeybee trehalase. Biosci. Biotechnol. Biochem. 73 (2009) 2466–2473. [DOI] [PMID: 19897915]

[EC 3.2.1.28 created 1961, modified 2012]

3.5.1.110

Accepted name:

ureidoacrylate amidohydrolase

Reaction:

(1) (Z)-3-ureidoacrylate + H₂O = (Z)-3-aminoacrylate + CO₂ + NH₃ (overall reaction)
(1a) (Z)-3-ureidoacrylate + H₂O = (Z)-3-aminoacrylate + carbamate
(1b) carbamate = CO₂ + NH₃ (spontaneous)
(2) (Z)-2-methylureidoacrylate + H₂O = (Z)-2-methylaminoacrylate + CO₂ + NH₃ (overall reaction)
(2a) (Z)-2-methylureidoacrylate + H₂O = (Z)-2-methylaminoacrylate + carbamate
(2b) carbamate = CO₂ + NH₃ (spontaneous)

For diagram of pyrimidine catabolism, click here

Glossary:

(Z)-3-ureidoacrylate = (2Z)-3-(carbamoylamino)prop-2-enoate
(Z)-2-methylureidoacrylate = (2Z)-3-(carbamoylamino)-2-methylprop-2-enoate

Other name(s):

peroxyureidoacrylate/ureidoacrylate amidohydrolase; rutB (gene name); (Z)-3-ureidoacrylate peracid amidohydrolase

Systematic name:

(Z)-3-ureidoacrylate amidohydrolase

Comments:

The enzyme participates in the Rut pyrimidine catabolic pathway.

Links to other databases:

References:

1.	Kim, K.S., Pelton, J.G., Inwood, W.B., Andersen, U., Kustu, S. and Wemmer, D.E. The Rut pathway for pyrimidine degradation: novel chemistry and toxicity problems. J. Bacteriol. 192 (2010) 4089–4102. [DOI] [PMID: 20400551]

[EC 3.5.1.110 created 2012, modified 2020]

4.1.1.94

Accepted name:

ethylmalonyl-CoA decarboxylase

Reaction:

(S)-ethylmalonyl-CoA = butanoyl-CoA + CO₂

Systematic name:

(S)-ethylmalonyl-CoA carboxy-lyase (butanoyl-CoA-forming)

Comments:

The enzyme, which exists in all vertebrates, decarboxylates ethylmalonyl-CoA, a potentially toxic compound that is formed in low amounts by the activity of EC 6.4.1.2, acetyl-CoA carboxylase and EC 6.4.1.3, propionyl-CoA carboxylase. It prefers the S isomer, and can decarboxylate (R)-ethylmalonyl-CoA with lower efficiency. cf. EC 7.2.4.3, (S)-methylmalonyl-CoA decarboxylase (sodium-transporting).

Links to other databases:

References:

1.	Linster, C.L., Noel, G., Stroobant, V., Vertommen, D., Vincent, M.F., Bommer, G.T., Veiga-da-Cunha, M. and Van Schaftingen, E. Ethylmalonyl-CoA decarboxylase, a new enzyme involved in metabolite proofreading. J. Biol. Chem. 286 (2011) 42992–43003. [DOI] [PMID: 22016388]

[EC 4.1.1.94 created 2012]

4.1.2.50

Accepted name:

6-carboxytetrahydropterin synthase

Reaction:

7,8-dihydroneopterin 3′-triphosphate + H₂O = 6-carboxy-5,6,7,8-tetrahydropterin + acetaldehyde + triphosphate

For diagram of queuine biosynthesis, click here

Glossary:

7,8-dihydroneopterin 3′-triphosphate = 2-amino-6-[(1S,2R)-1,2-dihydroxy-3-triphosphooxypropyl]-4-oxo-2,3,7,8-tetrahydropteridine
6-carboxy-5,6,7,8-tetrahydropterin = 2-amino-4-oxo-2,3,5,6,7,8-hexahydropteridine-6-carboxylate

Other name(s):

CPH4 synthase; queD (gene name); ToyB; ykvK (gene name)

Systematic name:

7,8-dihydroneopterin 3′-triphosphate acetaldehyde-lyase (6-carboxy-5,6,7,8-tetrahydropterin and triphosphate-forming)

Comments:

Binds Zn²⁺. Isolated from the bacteria Bacillus subtilis and Escherichia coli. The reaction is part of the biosynthesis pathway of queuosine.The enzyme from Escherichia coli can also convert 6-pyruvoyl-5,6,7,8-tetrahydropterin and sepiapterin to 6-carboxy-5,6,7,8-tetrahydropterin [2].

Links to other databases:

References:

1.	Cicmil, N. and Shi, L. Crystallization and preliminary X-ray characterization of queD from Bacillus subtilis, an enzyme involved in queuosine biosynthesis. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 64 (2008) 119–122. [DOI] [PMID: 18259064]
2.	McCarty, R.M., Somogyi, A. and Bandarian, V. Escherichia coli QueD is a 6-carboxy-5,6,7,8-tetrahydropterin synthase. Biochemistry 48 (2009) 2301–2303. [DOI] [PMID: 19231875]

[EC 4.1.2.50 created 2012]

4.2.1.132

Accepted name:

2-hydroxyhexa-2,4-dienoate hydratase

Reaction:

4-hydroxy-2-oxohexanoate = (2Z,4Z)-2-hydroxyhexa-2,4-dienoate + H₂O

Other name(s):

tesE (gene name); hsaE (gene name)

Systematic name:

4-hydroxy-2-oxohexanoate hydro-lyase [(2Z,4Z)-2-hydroxyhexa-2,4-dienoate-forming]

Comments:

This enzyme catalyses a late step in the bacterial steroid degradation pathway. The product, 4-hydroxy-2-oxohexanoate, forms a 2-hydroxy-4-hex-2-enolactone under acidic conditions.

Links to other databases:

BRENDA, EAWAG-BBD, EXPASY, Gene, KEGG, PDB

References:

Horinouchi, M., Hayashi, T., Koshino, H., Kurita, T. and Kudo, T. Identification of 9,17-dioxo-1,2,3,4,10,19-hexanorandrostan-5-oic acid, 4-hydroxy-2-oxohexanoic acid, and 2-hydroxyhexa-2,4-dienoic acid and related enzymes involved in testosterone degradation in Comamonas testosteroni TA441. Appl. Environ. Microbiol. 71 (2005) 5275–5281. [DOI] [PMID: 16151114]

[EC 4.2.1.132 created 2012]

4.2.3.14

Deleted entry:

pinene synthase. Now covered by EC 4.2.3.119, (-)-α-pinene synthase, and EC 4.2.3.120, (-)-β-pinene synthase

[EC 4.2.3.14 created 2000 as EC 4.1.99.8, transferred 2000 to EC 4.2.3.14, deleted 2012]

4.2.3.105

Accepted name:

tricyclene synthase

Reaction:

geranyl diphosphate = tricyclene + diphosphate

For diagram of bornane and related monoterpenoids, click here

Other name(s):

TPS3

Systematic name:

geranyl-diphosphate diphosphate-lyase (cyclizing; tricyclene-forming)

Comments:

The enzyme from Solanum lycopersicum (tomato) gives a mixture of tricyclene, camphene, β-myrcene, limonene, and traces of several other monoterpenoids. See EC 4.2.3.117. (-)-camphene synthase, EC 4.2.3.15, myrcene synthase and EC 4.2.3.16, (4S)-limonene synthase.

Links to other databases:

References:

1.	Falara, V., Akhtar, T.A., Nguyen, T.T., Spyropoulou, E.A., Bleeker, P.M., Schauvinhold, I., Matsuba, Y., Bonini, M.E., Schilmiller, A.L., Last, R.L., Schuurink, R.C. and Pichersky, E. The tomato terpene synthase gene family. Plant Physiol. 157 (2011) 770–789. [DOI] [PMID: 21813655]

[EC 4.2.3.105 created 2012]

4.2.3.106

Accepted name:

(E)-β-ocimene synthase

Reaction:

geranyl diphosphate = (E)-β-ocimene + diphosphate

Glossary:

(E)-β-ocimene = (3E)-3,7-dimethylocta-1,3,6-triene

Other name(s):

β-ocimene synthase; AtTPS03; ama0a23; LjEβOS; MtEBOS

Systematic name:

geranyl-diphosphate diphosphate-lyase [(E)-β-ocimene-forming]

Comments:

Widely distributed in plants, which release β-ocimene when attacked by herbivorous insects.

Links to other databases:

References:

1.	Faldt, J., Arimura, G., Gershenzon, J., Takabayashi, J. and Bohlmann, J. Functional identification of AtTPS03 as (E)-β-ocimene synthase: a monoterpene synthase catalyzing jasmonate- and wound-induced volatile formation in Arabidopsis thaliana. Planta 216 (2003) 745–751. [DOI] [PMID: 12624761]
2.	Dudareva, N., Martin, D., Kish, C.M., Kolosova, N., Gorenstein, N., Faldt, J., Miller, B. and Bohlmann, J. (E)-β-ocimene and myrcene synthase genes of floral scent biosynthesis in snapdragon: function and expression of three terpene synthase genes of a new terpene synthase subfamily. Plant Cell 15 (2003) 1227–1241. [DOI] [PMID: 12724546]
3.	Arimura, G., Ozawa, R., Kugimiya, S., Takabayashi, J. and Bohlmann, J. Herbivore-induced defense response in a model legume. Two-spotted spider mites induce emission of (E)-β-ocimene and transcript accumulation of (E)-β-ocimene synthase in Lotus japonicus. Plant Physiol. 135 (2004) 1976–1983. [DOI] [PMID: 15310830]
4.	Navia-Gine, W.G., Yuan, J.S., Mauromoustakos, A., Murphy, J.B., Chen, F. and Korth, K.L. Medicago truncatula (E)-β-ocimene synthase is induced by insect herbivory with corresponding increases in emission of volatile ocimene. Plant Physiol. Biochem. 47 (2009) 416–425. [DOI] [PMID: 19249223]

[EC 4.2.3.106 created 2012]

4.2.3.107

Accepted name:

(+)-car-3-ene synthase

Reaction:

geranyl diphosphate = (+)-car-3-ene + diphosphate

For diagram of monoterpenoid biosynthesis, click here

Glossary:

(+)-car-3-ene = (1S,6R)-3,7,7-trimethylbicyclo[4.1.0]hept-3-ene

Other name(s):

3-carene cyclase; 3-carene synthase; 3CAR; (+)-3-carene synthase

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (+)-car-3-ene-forming]

Comments:

The enzyme reacts with (3S)-linalyl diphosphate twice as rapidly as geranyl diphosphate, but 25 times as rapidly as (3R)-linalyl diphosphate. It is assumed that (3S)-linalyl diphosphate is normally formed as an enzyme bound intermediate in the reaction. In the reaction the 5-pro-R hydrogen of geranyl diphosphate is eliminated during cyclopropane ring formation [1,2]. In Picea abies (Norway spruce) and Picea sitchensis (Sitka spruce) terpinolene is also formed [4,6]. See EC 4.2.3.113 terpinolene synthase. (+)-Car-3-ene is associated with resistance of Picea sitchensis (Sitka spruce) to white pine weevil [6].

Links to other databases:

References:

1.	Savage, T.J. and Croteau, R. Biosynthesis of monoterpenes: regio- and stereochemistry of (+)-3-carene biosynthesis. Arch. Biochem. Biophys. 305 (1993) 581–587. [DOI] [PMID: 8373196]
2.	Savage, T.J., Ichii, H., Hume, S.D., Little, D.B. and Croteau, R. Monoterpene synthases from gymnosperms and angiosperms: stereospecificity and inactivation by cysteinyl- and arginyl-directed modifying reagents. Arch. Biochem. Biophys. 320 (1995) 257–265. [DOI] [PMID: 7625832]
3.	Savage, T.J., Hatch, M.W. and Croteau, R. Monoterpene synthases of Pinus contorta and related conifers. A new class of terpenoid cyclase. J. Biol. Chem. 269 (1994) 4012–4020. [PMID: 8307957]
4.	Faldt, J., Martin, D., Miller, B., Rawat, S. and Bohlmann, J. Traumatic resin defense in Norway spruce (Picea abies): methyl jasmonate-induced terpene synthase gene expression, and cDNA cloning and functional characterization of (+)-3-carene synthase. Plant Mol. Biol. 51 (2003) 119–133. [PMID: 12602896]
5.	Hamberger, B., Hall, D., Yuen, M., Oddy, C., Hamberger, B., Keeling, C.I., Ritland, C., Ritland, K. and Bohlmann, J. Targeted isolation, sequence assembly and characterization of two white spruce (Picea glauca) BAC clones for terpenoid synthase and cytochrome P₄₅₀ genes involved in conifer defence reveal insights into a conifer genome. BMC Plant Biol. 9:106 (2009). [DOI] [PMID: 19656416]
6.	Hall, D.E., Robert, J.A., Keeling, C.I., Domanski, D., Quesada, A.L., Jancsik, S., Kuzyk, M.A., Hamberger, B., Borchers, C.H. and Bohlmann, J. An integrated genomic, proteomic and biochemical analysis of (+)-3-carene biosynthesis in Sitka spruce (Picea sitchensis) genotypes that are resistant or susceptible to white pine weevil. Plant J. 65 (2011) 936–948. [DOI] [PMID: 21323772]

[EC 4.2.3.107 created 2012]

4.2.3.108

Accepted name:

1,8-cineole synthase

Reaction:

geranyl diphosphate + H₂O = 1,8-cineole + diphosphate

For diagram of menthane monoterpenoid biosynthesis, click here

Glossary:

1,8-cineole = 1,3,3-trimethyl-2-oxabicyclo[2.2.2]octane

Other name(s):

1,8-cineole cyclase; geranyl pyrophoshate:1,8-cineole cyclase; 1,8-cineole synthetase

Systematic name:

geranyl-diphosphate diphosphate-lyase (cyclizing, 1,8-cineole-forming)

Comments:

Requires Mn²⁺ or Zn²⁺. Mg²⁺ is less effective than either. 1,8-Cineole is the main product from the enzyme with just traces of other monoterpenoids. The oxygen atom is derived from water. The reaction proceeds via linalyl diphosphate and α-terpineol, the stereochemistry of both depends on the organism. However neither intermediate can substitute for geranyl diphosphate. The reaction in Salvia officinalis (sage) proceeds via (–)-(3R)-linalyl diphosphate [1-3] while that in Arabidopsis (rock cress) proceeds via (+)-(3S)-linalyl diphosphate [4].

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, PDB, CAS registry number: 110637-19-9

References:

1.	Croteau, R., Alonso, W.R., Koepp, A.E. and Johnson, M.A. Biosynthesis of monoterpenes: partial purification, characterization, and mechanism of action of 1,8-cineole synthase. Arch. Biochem. Biophys. 309 (1994) 184–192. [DOI] [PMID: 8117108]
2.	Wise, M.L., Savage, T.J., Katahira, E. and Croteau, R. Monoterpene synthases from common sage (Salvia officinalis). cDNA isolation, characterization, and functional expression of (+)-sabinene synthase, 1,8-cineole synthase, and (+)-bornyl diphosphate synthase. J. Biol. Chem. 273 (1998) 14891–14899. [DOI] [PMID: 9614092]
3.	Peters, R.J. and Croteau, R.B. Alternative termination chemistries utilized by monoterpene cyclases: chimeric analysis of bornyl diphosphate, 1,8-cineole, and sabinene synthases. Arch. Biochem. Biophys. 417 (2003) 203–211. [DOI] [PMID: 12941302]
4.	Chen, F., Ro, D.K., Petri, J., Gershenzon, J., Bohlmann, J., Pichersky, E. and Tholl, D. Characterization of a root-specific Arabidopsis terpene synthase responsible for the formation of the volatile monoterpene 1,8-cineole. Plant Physiol. 135 (2004) 1956–1966. [DOI] [PMID: 15299125]
5.	Keszei, A., Brubaker, C.L., Carter, R., Kollner, T., Degenhardt, J. and Foley, W.J. Functional and evolutionary relationships between terpene synthases from Australian Myrtaceae. Phytochemistry 71 (2010) 844–852. [DOI] [PMID: 20399476]

[EC 4.2.3.108 created 2012]

4.2.3.109

Accepted name:

(-)-sabinene synthase

Reaction:

geranyl diphosphate = (-)-sabinene + diphosphate

For diagram of thujane monoterpenoid biosynthesis, click here

Glossary:

(-)-sabinene = (1S,5S)-1-isopropyl-4-methylenebicyclo[3.1.0]hexane

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (-)-sabinene-forming]

Comments:

Requires Mg²⁺. Isolated from Pinus contorta (lodgepole pine) as cyclase I [1] and from Conocephalum conicum (liverwort) [2].

Links to other databases:

References:

1.	Savage, T.J., Hatch, M.W. and Croteau, R. Monoterpene synthases of Pinus contorta and related conifers. A new class of terpenoid cyclase. J. Biol. Chem. 269 (1994) 4012–4020. [PMID: 8307957]
2.	Peters, R.J. and Croteau, R.B. Alternative termination chemistries utilized by monoterpene cyclases: chimeric analysis of bornyl diphosphate, 1,8-cineole, and sabinene synthases. Arch. Biochem. Biophys. 417 (2003) 203–211. [DOI] [PMID: 12941302]

[EC 4.2.3.109 created 2012]

4.2.3.110

Accepted name:

(+)-sabinene synthase

Reaction:

geranyl diphosphate = (+)-sabinene + diphosphate

For diagram of thujane monoterpenoid biosynthesis, click here

Glossary:

(+)-sabinene = (+)-thuj-4(10)-ene = (1R,5R)-1-isopropyl-4-methylenebicyclo[3.1.0]hexane

Other name(s):

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (+)-sabinene-forming]

Comments:

Isolated from Salvia officinalis (sage). The recombinant enzyme gave 63% (+)-sabinene, 21% γ-terpinene, and traces of other monoterpenoids. See EC 4.2.3.114 γ-terpinene synthase.

Links to other databases:

References:

1.	Wise, M.L., Savage, T.J., Katahira, E. and Croteau, R. Monoterpene synthases from common sage (Salvia officinalis). cDNA isolation, characterization, and functional expression of (+)-sabinene synthase, 1,8-cineole synthase, and (+)-bornyl diphosphate synthase. J. Biol. Chem. 273 (1998) 14891–14899. [DOI] [PMID: 9614092]
2.	Peters, R.J. and Croteau, R.B. Alternative termination chemistries utilized by monoterpene cyclases: chimeric analysis of bornyl diphosphate, 1,8-cineole, and sabinene synthases. Arch. Biochem. Biophys. 417 (2003) 203–211. [DOI] [PMID: 12941302]

[EC 4.2.3.110 created 2012]

4.2.3.111

Accepted name:

(-)-α-terpineol synthase

Reaction:

geranyl diphosphate + H₂O = (-)-α-terpineol + diphosphate

For diagram of menthane monoterpenoid biosynthesis, click here

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (-)-α-terpineol-forming]

Comments:

The enzyme has been characterized from Vitis vinifera (grape). Also forms some 1,8-cineole and traces of other monoterpenoids.

Links to other databases:

References:

1.	Martin, D.M. and Bohlmann, J. Identification of Vitis vinifera (-)-α-terpineol synthase by in silico screening of full-length cDNA ESTs and functional characterization of recombinant terpene synthase. Phytochemistry 65 (2004) 1223–1229. [DOI] [PMID: 15184006]
2.	Lucker, J., Bowen, P. and Bohlmann, J. Vitis vinifera terpenoid cyclases: functional identification of two sesquiterpene synthase cDNAs encoding (+)-valencene synthase and (-)-germacrene D synthase and expression of mono- and sesquiterpene synthases in grapevine flowers and berries. Phytochemistry 65 (2004) 2649–2659. [DOI] [PMID: 15464152]

[EC 4.2.3.111 created 2012]

4.2.3.112

Accepted name:

(+)-α-terpineol synthase

Reaction:

geranyl diphosphate + H₂O = (+)-α-terpineol + diphosphate

For diagram of menthane monoterpenoid biosynthesis, click here

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (+)-α-terpineol-forming]

Comments:

The enzyme has been characterized from Santalum album (sandalwood). Also forms some (-)-limonene and traces of other monoterpenoids. See EC 4.2.3.16 (4S)-limonene synthase.

Links to other databases:

References:

1.	Jones, C.G., Keeling, C.I., Ghisalberti, E.L., Barbour, E.L., Plummer, J.A. and Bohlmann, J. Isolation of cDNAs and functional characterisation of two multi-product terpene synthase enzymes from sandalwood, Santalum album L. Arch. Biochem. Biophys. 477 (2008) 121–130. [DOI] [PMID: 18541135]

[EC 4.2.3.112 created 2012]

4.2.3.113

Accepted name:

terpinolene synthase

Reaction:

geranyl diphosphate = terpinolene + diphosphate

For diagram of menthane monoterpenoid biosynthesis, click here

Glossary:

terpinolene = 1-methyl-4-(propan-2-ylidene)cyclohexene

Other name(s):

ag9; PmeTPS2; LaLIMS_RR

Systematic name:

geranyl-diphosphate diphosphate-lyase (cyclizing, terpinolene-forming)

Comments:

Requires Mg²⁺. Mn²⁺ is less effective and product ratio changes. Forms traces of other monoterpenoids.

Links to other databases:

References:

1.	Croteau, R. and Satterwhite, D.M. Biosynthesis of monoterpenes. Stereochemical implications of acyclic and monocyclic olefin formation by (+)- and (-)-pinene cyclases from sage. J. Biol. Chem. 264 (1989) 15309–15315. [PMID: 2768265]
2.	Bohlmann, J., Phillips, M., Ramachandiran, V., Katoh, S. and Croteau, R. cDNA cloning, characterization, and functional expression of four new monoterpene synthase members of the Tpsd gene family from grand fir (Abies grandis). Arch. Biochem. Biophys. 368 (1999) 232–243. [DOI] [PMID: 10441373]
3.	Faldt, J., Martin, D., Miller, B., Rawat, S. and Bohlmann, J. Traumatic resin defense in Norway spruce (Picea abies): methyl jasmonate-induced terpene synthase gene expression, and cDNA cloning and functional characterization of (+)-3-carene synthase. Plant Mol. Biol. 51 (2003) 119–133. [PMID: 12602896]
4.	Huber, D.P.W., Philippe, R.N., Godard, K.-A., Sturrock, R.N. and Bohlmann, J. Characterization of four terpene synthase cDNAs from methyl jasmonate-induced Douglas-fir, Pseudotsuga menziesii. Phytochemistry 66 (2005) 1427–1439. [DOI] [PMID: 15921711]
5.	Landmann, C., Fink, B., Festner, M., Dregus, M., Engel, K.H. and Schwab, W. Cloning and functional characterization of three terpene synthases from lavender (Lavandula angustifolia). Arch. Biochem. Biophys. 465 (2007) 417–429. [DOI] [PMID: 17662687]

[EC 4.2.3.113 created 2012]

4.2.3.114

Accepted name:

γ-terpinene synthase

Reaction:

geranyl diphosphate = γ-terpinene + diphosphate

For diagram of menthane monoterpenoid biosynthesis, click here

Glossary:

γ-terpinene = 1-isopropyl-4-methylcyclohexa-1,4-diene

Other name(s):

OvTPS2; ClcTS

Systematic name:

geranyl-diphosphate diphosphate-lyase (cyclizing, γ-terpinene-forming)

Comments:

Isolated from Thymus vulgaris (thyme) [1,2], Citrus limon (lemon) [3], Citrus unshiu (satsuma) [4] and Origanum vulgare (oregano) [5]. Requires Mg²⁺. Mn²⁺ less effective. The reaction involves a 1,2-hydride shift. The 5-pro-S hydrogen of geranyl diphosphate is lost. Traces of several other monoterpenoids are formed in addition to γ-terpinene.

Links to other databases:

References:

1.	Alonso, W.R. and Croteau, R. Purification and characterization of the monoterpene cyclase γ-terpinene synthase from Thymus vulgaris. Arch. Biochem. Biophys. 286 (1991) 511–517. [DOI] [PMID: 1897973]
2.	LaFever, R.E. and Croteau, R. Hydride shifts in the biosynthesis of the p-menthane monoterpenes α-terpinene, γ-terpinene, and β-phellandrene. Arch. Biochem. Biophys. 301 (1993) 361–366. [DOI] [PMID: 8460944]
3.	Lücker, J., El Tamer, M.K., Schwab, W., Verstappen, F.W., van der Plas, L.H., Bouwmeester, H.J. and Verhoeven, H.A. Monoterpene biosynthesis in lemon (Citrus limon). cDNA isolation and functional analysis of four monoterpene synthases. Eur. J. Biochem. 269 (2000) 3160–3171. [DOI] [PMID: 12084056]
4.	Suzuki, Y., Sakai, H., Shimada, T., Omura, M., Kumazawa, S. and Nakayama, T. Characterization of γ-terpinene synthase from Citrus unshiu (Satsuma mandarin). Biofactors 21 (2004) 79–82. [PMID: 15630174]
5.	Crocoll, C., Asbach, J., Novak, J., Gershenzon, J. and Degenhardt, J. Terpene synthases of oregano (Origanum vulgare L.) and their roles in the pathway and regulation of terpene biosynthesis. Plant Mol. Biol. 73 (2010) 587–603. [DOI] [PMID: 20419468]

[EC 4.2.3.114 created 2012]

4.2.3.115

Accepted name:

α-terpinene synthase

Reaction:

geranyl diphosphate = α-terpinene + diphosphate

For diagram of menthane monoterpenoid biosynthesis, click here

Glossary:

α-terpinene = 1-isopropyl-4-methylcyclohexa-1,3-diene

Systematic name:

geranyl-diphosphate diphosphate-lyase (cyclizing, α-terpinene-forming)

Comments:

The enzyme has been characterized from Dysphania ambrosioides (American wormseed). Requires Mg²⁺. Mn²⁺ is less effective. The enzyme will also use (3R)-linalyl diphosphate. The reaction involves a 1,2-hydride shift. The 1-pro-S hydrogen of geranyl diphosphate is lost.

Links to other databases:

References:

1.	Poulose, A.J. and Croteau, R. γ-Terpinene synthetase: a key enzyme in the biosynthesis of aromatic monoterpenes. Arch. Biochem. Biophys. 191 (1978) 400–411. [DOI] [PMID: 736574]
2.	LaFever, R.E. and Croteau, R. Hydride shifts in the biosynthesis of the p-menthane monoterpenes α-terpinene, γ-terpinene, and β-phellandrene. Arch. Biochem. Biophys. 301 (1993) 361–366. [DOI] [PMID: 8460944]

[EC 4.2.3.115 created 2012]

4.2.3.116

Accepted name:

(+)-camphene synthase

Reaction:

geranyl diphosphate = (+)-camphene + diphosphate

Glossary:

(+)-camphene = (1R,4S)-2,2-dimethyl-3-methylenebicyclo[2.2.1]heptane

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (+)-camphene-forming]

Comments:

Cyclase I of Salvia officinalis (sage) gives about equal parts (+)-camphene and (+)-α-pinene. (3R)-Linalyl diphosphate can also be used by the enzyme in preference to (3S)-linalyl diphosphate. Requires Mg²⁺ (preferred to Mn²⁺). See also EC 4.2.3.121 (+)-α-pinene synthase.

Links to other databases:

References:

1.	Gambliel, H. and Croteau, R. Pinene cyclases I and II. Two enzymes from sage (Salvia officinalis) which catalyze stereospecific cyclizations of geranyl pyrophosphate to monoterpene olefins of opposite configuration. J. Biol. Chem. 259 (1984) 740–748. [PMID: 6693393]
2.	Croteau, R., Satterwhite, D.M., Cane, D.E. and Chang, C.C. Biosynthesis of monoterpenes. Enantioselectivity in the enzymatic cyclization of (+)- and (-)-linalyl pyrophosphate to (+)- and (-)-pinene and (+)- and (-)-camphene. J. Biol. Chem. 263 (1988) 10063–10071. [PMID: 3392006]
3.	Wagschal, K.C., Pyun, H.J., Coates, R.M. and Croteau, R. Monoterpene biosynthesis: isotope effects associated with bicyclic olefin formation catalyzed by pinene synthases from sage (Salvia officinalis). Arch. Biochem. Biophys. 308 (1994) 477–487. [DOI] [PMID: 8109978]
4.	Pyun, H.J., Wagschal, K.C., Jung, D.I., Coates, R.M. and Croteau, R. Stereochemistry of the proton elimination in the formation of (+)- and (-)-α-pinene by monoterpene cyclases from sage (Salvia officinalis). Arch. Biochem. Biophys. 308 (1994) 488–496. [DOI] [PMID: 8109979]

[EC 4.2.3.116 created 2012]

4.2.3.117

Accepted name:

(-)-camphene synthase

Reaction:

geranyl diphosphate = (-)-camphene + diphosphate

Glossary:

(-)-camphene = (1S,4R)-2,2-dimethyl-3-methylenebicyclo[2.2.1]heptane

Other name(s):

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (-)-camphene-forming]

Comments:

(-)-Camphene is the major product in Abies grandis (grand fir) with traces of other monoterpenoids [1]. In Pseudotsuga menziesii (Douglas-fir) there are about equal parts of (-)-camphene and (-)-α-pinene with traces of four other monoterpenoids [2,3]. In Solanum lycopersicum (tomato) tricyclene, β-myrcene, limonene, and traces of several other monoterpenoids are also formed [4]. See also EC 4.2.3.15 myrcene synthase, EC 4.2.3.16 (4S)-limonene synthase, EC 4.2.3.119 (-)-α-pinene synthase and EC 4.2.3.105 tricyclene synthase.

Links to other databases:

References:

1.	Bohlmann, J., Phillips, M., Ramachandiran, V., Katoh, S. and Croteau, R. cDNA cloning, characterization, and functional expression of four new monoterpene synthase members of the Tpsd gene family from grand fir (Abies grandis). Arch. Biochem. Biophys. 368 (1999) 232–243. [DOI] [PMID: 10441373]
2.	Huber, D.P.W., Philippe, R.N., Godard, K.-A., Sturrock, R.N. and Bohlmann, J. Characterization of four terpene synthase cDNAs from methyl jasmonate-induced Douglas-fir, Pseudotsuga menziesii. Phytochemistry 66 (2005) 1427–1439. [DOI] [PMID: 15921711]
3.	Hyatt, D.C. and Croteau, R. Mutational analysis of a monoterpene synthase reaction: altered catalysis through directed mutagenesis of (-)-pinene synthase from Abies grandis. Arch. Biochem. Biophys. 439 (2005) 222–233. [DOI] [PMID: 15978541]
4.	Falara, V., Akhtar, T.A., Nguyen, T.T., Spyropoulou, E.A., Bleeker, P.M., Schauvinhold, I., Matsuba, Y., Bonini, M.E., Schilmiller, A.L., Last, R.L., Schuurink, R.C. and Pichersky, E. The tomato terpene synthase gene family. Plant Physiol. 157 (2011) 770–789. [DOI] [PMID: 21813655]

[EC 4.2.3.117 created 2012]

4.2.3.118

Accepted name:

2-methylisoborneol synthase

Reaction:

(E)-2-methylgeranyl diphosphate + H₂O = 2-methylisoborneol + diphosphate

For diagram of bornane and related monoterpenoids, click here and for diagram of reaction, click here

Other name(s):

sco7700; 2-MIB cyclase; MIB synthase; MIBS

Systematic name:

(E)-2-methylgeranyl-diphosphate diphosphate-lyase (cyclizing, 2-methylisoborneol-forming)

Comments:

The product, 2-methylisoborneol, is a characteristc odiferous compound with a musty smell produced by soil microorganisms.

Links to other databases:

References:

1.	Wang, C.M. and Cane, D.E. Biochemistry and molecular genetics of the biosynthesis of the earthy odorant methylisoborneol in Streptomyces coelicolor. J. Am. Chem. Soc. 130 (2008) 8908–8909. [DOI] [PMID: 18563898]
2.	Komatsu, M., Tsuda, M., Omura, S., Oikawa, H. and Ikeda, H. Identification and functional analysis of genes controlling biosynthesis of 2-methylisoborneol. Proc. Natl. Acad. Sci. USA 105 (2008) 7422–7427. [DOI] [PMID: 18492804]
3.	Giglio, S., Chou, W.K., Ikeda, H., Cane, D.E. and Monis, P.T. Biosynthesis of 2-methylisoborneol in cyanobacteria. Environ. Sci. Technol. 45 (2011) 992–998. [DOI] [PMID: 21174459]

[EC 4.2.3.118 created 2012]

4.2.3.119

Accepted name:

(-)-α-pinene synthase

Reaction:

geranyl diphosphate = (-)-α-pinene + diphosphate

For diagram of pinene and related monoterpenoids, click here

Glossary:

(-)-α-pinene = (1S,5S)-2,6,6-trimethylbicyclo[3.1.1]hept-2-ene

Other name(s):

(-)-α-pinene/(-)-camphene synthase; (-)-α-pinene cyclase

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (-)-α-pinene-forming]

Comments:

Cyclase II of Salvia officinalis (sage) gives about equal parts (-)-α-pinene, (-)-β-pinene and (-)-camphene, plus traces of other monoterpenoids. (3S)-Linalyl diphosphate can also be used by the enzyme in preference to (3R)-linalyl diphosphate. The 4-pro-S-hydrogen of geranyl diphosphate is lost. Requires Mg²⁺ (preferred to Mn²⁺) [1-6]. The enzyme from Abies grandis (grand fir) gives roughly equal parts (-)-α-pinene and (-)-β-pinene. However the clone ag11 gave 35% (-)-limonene, 24% (-)-α-pinene and 20% (-)-β-phellandrene. It requires Mn²⁺ and K⁺ (Mg²⁺ is ineffective) [7-10]. Synthase I from Pinus taeda (loblolly pine) produces (-)-α-pinene with traces of (-)-β-pinene and requires Mn²⁺ (preferred to Mg²⁺) [11,12]. The enzyme from Picea sitchensis (Sika spruce) forms 70% (-)-α-pinene and 30% (-)-β-pinene [13]. The recombinant PmeTPS1 enzyme from Pseudotsuga menziesii (Douglas fir) gave roughly equal proportions of (-)-α-pinene and (-)-camphene plus traces of other monoterpenoids [14]. See also EC 4.2.3.120, (-)-β-pinene synthase; EC 4.2.3.117, (-)-camphene synthase; EC 4.2.3.16, (-)-limonene synthase; and EC 4.2.3.52, (-)-β-phellandrene synthase.

Links to other databases:

References:

1.	Gambliel, H. and Croteau, R. Pinene cyclases I and II. Two enzymes from sage (Salvia officinalis) which catalyze stereospecific cyclizations of geranyl pyrophosphate to monoterpene olefins of opposite configuration. J. Biol. Chem. 259 (1984) 740–748. [PMID: 6693393]
2.	Croteau, R.B., Wheeler, C.J., Cane, D.E., Ebert, R. and Ha, H.J. Isotopically sensitive branching in the formation of cyclic monoterpenes: proof that (-)-α-pinene and (-)-β-pinene are synthesized by the same monoterpene cyclase via deprotonation of a common intermediate. Biochemistry 26 (1987) 5383–5389. [PMID: 3314988]
3.	Croteau, R., Satterwhite, D.M., Cane, D.E. and Chang, C.C. Biosynthesis of monoterpenes. Enantioselectivity in the enzymatic cyclization of (+)- and (-)-linalyl pyrophosphate to (+)- and (-)-pinene and (+)- and (-)-camphene. J. Biol. Chem. 263 (1988) 10063–10071. [PMID: 3392006]
4.	Croteau, R. and Satterwhite, D.M. Biosynthesis of monoterpenes. Stereochemical implications of acyclic and monocyclic olefin formation by (+)- and (-)-pinene cyclases from sage. J. Biol. Chem. 264 (1989) 15309–15315. [PMID: 2768265]
5.	Pyun, H.J., Wagschal, K.C., Jung, D.I., Coates, R.M. and Croteau, R. Stereochemistry of the proton elimination in the formation of (+)- and (-)-α-pinene by monoterpene cyclases from sage (Salvia officinalis). Arch. Biochem. Biophys. 308 (1994) 488–496. [DOI] [PMID: 8109979]
6.	Lu, S., Xu, R., Jia, J.W., Pang, J., Matsuda, S.P. and Chen, X.Y. Cloning and functional characterization of a β-pinene synthase from Artemisia annua that shows a circadian pattern of expression. Plant Physiol. 130 (2002) 477–486. [DOI] [PMID: 12226526]
7.	Lewinsohn, E., Gijzen, M. and Croteau, R. Wound-inducible pinene cyclase from grand fir: purification, characterization, and renaturation after SDS-PAGE. Arch. Biochem. Biophys. 293 (1992) 167–173. [DOI] [PMID: 1731633]
8.	Bohlmann, J., Steele, C.L. and Croteau, R. Monoterpene synthases from grand fir (Abies grandis). cDNA isolation, characterization, and functional expression of myrcene synthase, (-)-(4S)-limonene synthase, and (-)-(1S,5S)-pinene synthase. J. Biol. Chem. 272 (1997) 21784–21792. [DOI] [PMID: 9268308]
9.	Bohlmann, J., Phillips, M., Ramachandiran, V., Katoh, S. and Croteau, R. cDNA cloning, characterization, and functional expression of four new monoterpene synthase members of the Tpsd gene family from grand fir (Abies grandis). Arch. Biochem. Biophys. 368 (1999) 232–243. [DOI] [PMID: 10441373]
10.	Hyatt, D.C. and Croteau, R. Mutational analysis of a monoterpene synthase reaction: altered catalysis through directed mutagenesis of (-)-pinene synthase from Abies grandis. Arch. Biochem. Biophys. 439 (2005) 222–233. [DOI] [PMID: 15978541]
11.	Phillips, M.A., Savage, T.J. and Croteau, R. Monoterpene synthases of loblolly pine (Pinus taeda) produce pinene isomers and enantiomers. Arch. Biochem. Biophys. 372 (1999) 197–204. [DOI] [PMID: 10562434]
12.	Phillips, M.A., Wildung, M.R., Williams, D.C., Hyatt, D.C. and Croteau, R. cDNA isolation, functional expression, and characterization of (+)-α-pinene synthase and (-)-α-pinene synthase from loblolly pine (Pinus taeda): stereocontrol in pinene biosynthesis. Arch. Biochem. Biophys. 411 (2003) 267–276. [DOI] [PMID: 12623076]
13.	McKay, S.A., Hunter, W.L., Godard, K.A., Wang, S.X., Martin, D.M., Bohlmann, J. and Plant, A.L. Insect attack and wounding induce traumatic resin duct development and gene expression of (-)-pinene synthase in Sitka spruce. Plant Physiol. 133 (2003) 368–378. [DOI] [PMID: 12970502]
14.	Huber, D.P.W., Philippe, R.N., Godard, K.-A., Sturrock, R.N. and Bohlmann, J. Characterization of four terpene synthase cDNAs from methyl jasmonate-induced Douglas-fir, Pseudotsuga menziesii. Phytochemistry 66 (2005) 1427–1439. [DOI] [PMID: 15921711]

[EC 4.2.3.119 created 2012]

4.2.3.120

Accepted name:

(-)-β-pinene synthase

Reaction:

geranyl diphosphate = (-)-β-pinene + diphosphate

For diagram of pinene and related monoterpenoids, click here

Glossary:

(-)-β-pinene = (1S,5S)-6,6-dimethyl-2-methylenebicyclo[3.1.1]hept-2-ene

Other name(s):

β-geraniolene synthase; (-)-(1S,5S)-pinene synthase; geranyldiphosphate diphosphate lyase (pinene forming)

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (-)-β-pinene-forming]

Comments:

Cyclase II of Salvia officinalis (sage) produces about equal parts (-)-α-pinene, (-)-β-pinene and (-)-camphene, plus traces of other monoterpenoids. The enzyme, which requires Mg²⁺ (preferred to Mn²⁺), can also use (3S)-Linalyl diphosphate (preferred to (3R)-linalyl diphosphate) [1-4]. The enzyme from Abies grandis (grand fir) produces roughly equal parts of (-)-α-pinene and (-)-β-pinene [6-9]. Cyclase IV from Pinus contorta (lodgepole pine) produces 63% (-)-β-pinene, 26% 3-carene, and traces of α-pinene [10]. Synthase III from Pinus taeda (loblolly pine) forms (-)-β-pinene with traces of α-pinene and requires Mn²⁺ and K⁺ (Mg²⁺ is ineffective) [11]. A cloned enzyme from Artemisia annua (sweet wormwood) gave (-)-β-pinene with traces of (-)-α-pinene [5]. The enzyme from Picea sitchensis (Sika spruce) forms 30% (-)-β-pinene and 70% (-)-α-pinene [12]. See also EC 4.2.3.119, (-)-α-pinene synthase, EC 4.2.3.117, (-)-camphene synthase, and EC 4.2.3.107 (+)-3-carene synthase.

Links to other databases:

References:

1.	Croteau, R.B., Wheeler, C.J., Cane, D.E., Ebert, R. and Ha, H.J. Isotopically sensitive branching in the formation of cyclic monoterpenes: proof that (-)-α-pinene and (-)-β-pinene are synthesized by the same monoterpene cyclase via deprotonation of a common intermediate. Biochemistry 26 (1987) 5383–5389. [PMID: 3314988]
2.	Croteau, R. and Satterwhite, D.M. Biosynthesis of monoterpenes. Stereochemical implications of acyclic and monocyclic olefin formation by (+)- and (-)-pinene cyclases from sage. J. Biol. Chem. 264 (1989) 15309–15315. [PMID: 2768265]
3.	Croteau, R., Satterwhite, D.M., Cane, D.E. and Chang, C.C. Biosynthesis of monoterpenes. Enantioselectivity in the enzymatic cyclization of (+)- and (-)-linalyl pyrophosphate to (+)- and (-)-pinene and (+)- and (-)-camphene. J. Biol. Chem. 263 (1988) 10063–10071. [PMID: 3392006]
4.	Pyun, H.J., Wagschal, K.C., Jung, D.I., Coates, R.M. and Croteau, R. Stereochemistry of the proton elimination in the formation of (+)- and (-)-α-pinene by monoterpene cyclases from sage (Salvia officinalis). Arch. Biochem. Biophys. 308 (1994) 488–496. [DOI] [PMID: 8109979]
5.	Lu, S., Xu, R., Jia, J.W., Pang, J., Matsuda, S.P. and Chen, X.Y. Cloning and functional characterization of a β-pinene synthase from Artemisia annua that shows a circadian pattern of expression. Plant Physiol. 130 (2002) 477–486. [DOI] [PMID: 12226526]
6.	Gijzen, M., Lewinsohn, E. and Croteau, R. Characterization of the constitutive and wound-inducible monoterpene cyclases of grand fir (Abies grandis). Arch. Biochem. Biophys. 289 (1991) 267–273. [DOI] [PMID: 1898071]
7.	Lewinsohn, E., Gijzen, M. and Croteau, R. Wound-inducible pinene cyclase from grand fir: purification, characterization, and renaturation after SDS-PAGE. Arch. Biochem. Biophys. 293 (1992) 167–173. [DOI] [PMID: 1731633]
8.	Bohlmann, J., Steele, C.L. and Croteau, R. Monoterpene synthases from grand fir (Abies grandis). cDNA isolation, characterization, and functional expression of myrcene synthase, (-)-(4S)-limonene synthase, and (-)-(1S,5S)-pinene synthase. J. Biol. Chem. 272 (1997) 21784–21792. [DOI] [PMID: 9268308]
9.	Hyatt, D.C. and Croteau, R. Mutational analysis of a monoterpene synthase reaction: altered catalysis through directed mutagenesis of (-)-pinene synthase from Abies grandis. Arch. Biochem. Biophys. 439 (2005) 222–233. [DOI] [PMID: 15978541]
10.	Savage, T.J., Ichii, H., Hume, S.D., Little, D.B. and Croteau, R. Monoterpene synthases from gymnosperms and angiosperms: stereospecificity and inactivation by cysteinyl- and arginyl-directed modifying reagents. Arch. Biochem. Biophys. 320 (1995) 257–265. [DOI] [PMID: 7625832]
11.	Phillips, M.A., Savage, T.J. and Croteau, R. Monoterpene synthases of loblolly pine (Pinus taeda) produce pinene isomers and enantiomers. Arch. Biochem. Biophys. 372 (1999) 197–204. [DOI] [PMID: 10562434]
12.	McKay, S.A., Hunter, W.L., Godard, K.A., Wang, S.X., Martin, D.M., Bohlmann, J. and Plant, A.L. Insect attack and wounding induce traumatic resin duct development and gene expression of (-)-pinene synthase in Sitka spruce. Plant Physiol. 133 (2003) 368–378. [DOI] [PMID: 12970502]

[EC 4.2.3.120 created 2012]

4.2.3.121

Accepted name:

(+)-α-pinene synthase

Reaction:

geranyl diphosphate = (+)-α-pinene + diphosphate

For diagram of pinene and related monoterpenoids, click here

Glossary:

(+)-α-pinene = (1R,5R)-2,6,6-trimethylbicyclo[3.1.1]hept-2-ene

Other name(s):

(+)-α-pinene cyclase; cyclase I

Systematic name:

geranyl-diphosphate diphosphate-lyase [cyclizing, (+)-α-pinene-forming]

Comments:

Cyclase I of Salvia officinalis (sage) gives about equal parts (+)-α-pinene and (+)-camphene, whereas cyclase III gives about equal parts of (+)-α-pinene and (+)-β-pinene. (3R)-Linalyl diphosphate can also be used by the enzyme in preference to (3S)-linalyl diphosphate. The 4-pro-R-hydrogen of geranyl diphosphate is lost. Requires Mg²⁺ (preferred to Mn²⁺) [1-4]. With synthase II of Pinus taeda (loblolly pine) (+)-α-pinene was the only product [5,6]. Requires Mn²⁺ (preferred to Mg²⁺). See also EC 4.2.3.122, (+)-β-pinene synthase, and EC 4.2.3.116, (+)-camphene synthase.

Links to other databases:

References:

1.	Gambliel, H. and Croteau, R. Pinene cyclases I and II. Two enzymes from sage (Salvia officinalis) which catalyze stereospecific cyclizations of geranyl pyrophosphate to monoterpene olefins of opposite configuration. J. Biol. Chem. 259 (1984) 740–748. [PMID: 6693393]
2.	Croteau, R., Satterwhite, D.M., Cane, D.E. and Chang, C.C. Biosynthesis of monoterpenes. Enantioselectivity in the enzymatic cyclization of (+)- and (-)-linalyl pyrophosphate to (+)- and (-)-pinene and (+)- and (-)-camphene. J. Biol. Chem. 263 (1988) 10063–10071. [PMID: 3392006]
3.	Wagschal, K.C., Pyun, H.J., Coates, R.M. and Croteau, R. Monoterpene biosynthesis: isotope effects associated with bicyclic olefin formation catalyzed by pinene synthases from sage (Salvia officinalis). Arch. Biochem. Biophys. 308 (1994) 477–487. [DOI] [PMID: 8109978]
4.	Pyun, H.J., Wagschal, K.C., Jung, D.I., Coates, R.M. and Croteau, R. Stereochemistry of the proton elimination in the formation of (+)- and (-)-α-pinene by monoterpene cyclases from sage (Salvia officinalis). Arch. Biochem. Biophys. 308 (1994) 488–496. [DOI] [PMID: 8109979]
5.	Phillips, M.A., Savage, T.J. and Croteau, R. Monoterpene synthases of loblolly pine (Pinus taeda) produce pinene isomers and enantiomers. Arch. Biochem. Biophys. 372 (1999) 197–204. [DOI] [PMID: 10562434]
6.	Phillips, M.A., Wildung, M.R., Williams, D.C., Hyatt, D.C. and Croteau, R. cDNA isolation, functional expression, and characterization of (+)-α-pinene synthase and (-)-α-pinene synthase from loblolly pine (Pinus taeda): stereocontrol in pinene biosynthesis. Arch. Biochem. Biophys. 411 (2003) 267–276. [DOI] [PMID: 12623076]

[EC 4.2.3.121 created 2012]

4.2.3.122

Accepted name:

(+)-β-pinene synthase

Reaction:

geranyl diphosphate = (+)-β-pinene + diphosphate

For diagram of pinene and related monoterpenoids, click here

Glossary:

(+)-β-pinene = (1R,5R)-6,6-dimethyl-2-methylenebicyclo[3.1.1]hept-2-ene

Other name(s):

(+)-pinene cyclase; cyclase III

Systematic name:

geranyl-diphosphate diphosphate-lyase [(+)-β-pinene-forming]

Comments:

Cyclase III from Salvia officinalis (sage) gives roughly equal parts of (+)-β-pinene and (+)-α-pinene. See EC 4.2.3.121, (+)-α-pinene synthase.

Links to other databases:

References:

1.	Wagschal, K.C., Pyun, H.J., Coates, R.M. and Croteau, R. Monoterpene biosynthesis: isotope effects associated with bicyclic olefin formation catalyzed by pinene synthases from sage (Salvia officinalis). Arch. Biochem. Biophys. 308 (1994) 477–487. [DOI] [PMID: 8109978]
2.	Pyun, H.J., Wagschal, K.C., Jung, D.I., Coates, R.M. and Croteau, R. Stereochemistry of the proton elimination in the formation of (+)- and (-)-α-pinene by monoterpene cyclases from sage (Salvia officinalis). Arch. Biochem. Biophys. 308 (1994) 488–496. [DOI] [PMID: 8109979]

[EC 4.2.3.122 created 2012]

4.2.3.123

Accepted name:

β-sesquiphellandrene synthase

Reaction:

(2E,6E)-farnesyl diphosphate = β-sesquiphellandrene + diphosphate

For diagram of bisabolene biosynthesis, click here and for diagram of β-sesquiphellandrene and zingiberene biosynthesis, click here

Other name(s):

Tps1; Os08g07100 (gene name)

Systematic name:

(2E,6E)-farnesyl-diphosphate diphosphate-lyase (cyclizing, β-sesquiphellandrene-forming)

Links to other databases:

References:

1.	Zhuang, X., Kollner, T.G., Zhao, N., Li, G., Jiang, Y., Zhu, L., Ma, J., Degenhardt, J. and Chen, F. Dynamic evolution of herbivore-induced sesquiterpene biosynthesis in sorghum and related grass crops. Plant J. 69 (2012) 70–80. [DOI] [PMID: 21880075]

[EC 4.2.3.123 created 2012]

5.3.2.5

Accepted name:

2,3-diketo-5-methylthiopentyl-1-phosphate enolase

Reaction:

5-(methylsulfanyl)-2,3-dioxopentyl phosphate = 2-hydroxy-5-(methylsulfanyl)-3-oxopent-1-enyl phosphate

Other name(s):

DK-MTP-1-P enolase; MtnW; YkrW; RuBisCO-like protein; RLP; 2,3-diketo-5-methylthiopentyl-1-phosphate keto—enol-isomerase

Systematic name:

5-(methylsulfanyl)-2,3-dioxopentyl phosphate keto—enol-isomerase

Comments:

The enzyme participates in the methionine salvage pathway in Bacillus subtilis [2].In some species a single bifunctional enzyme, EC 3.1.3.77, acireductone synthase, catalyses both this reaction and EC 3.1.3.87, 2-hydroxy-3-keto-5-methylthiopentenyl-1-phosphate phosphatase [1].

Links to other databases:

References:

1.	Myers, R.W., Wray, J.W., Fish, S. and Abeles, R.H. Purification and characterization of an enzyme involved in oxidative carbon-carbon bond cleavage reactions in the methionine salvage pathway of Klebsiella pneumoniae. J. Biol. Chem. 268 (1993) 24785–24791. [PMID: 8227039]
2.	Ashida, H., Saito, Y., Kojima, C., Kobayashi, K., Ogasawara, N. and Yokota, A. A functional link between RuBisCO-like protein of Bacillus and photosynthetic RuBisCO. Science 302 (2003) 286–290. [DOI] [PMID: 14551435]

[EC 5.3.2.5 created 2012]

5.3.99.10

Accepted name:

thiazole tautomerase

Reaction:

2-[(2R,5Z)-2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate = 2-(2-carboxy-4-methylthiazol-5-yl)ethyl phosphate

For diagram of thiamine diphosphate biosynthesis, click here

Glossary:

cThz*-P = 2-[(2R,5Z)-2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate
cThz-P = 2-(2-carboxy-4-methylthiazol-5-yl)ethyl phosphate = 4-methyl-5-[2-(phosphonooxy)ethyl]-1,3-thiazole-2-carboxylate

Other name(s):

tenI (gene name)

Systematic name:

2-(2-carboxy-4-methylthiazol-5-yl)ethyl phosphate isomerase

Comments:

The enzyme catalyses the irreversible aromatization of the thiazole moiety of 2-[(2R,5Z)-2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate.

Links to other databases:

References:

1.	Hazra, A.B., Han, Y., Chatterjee, A., Zhang, Y., Lai, R.Y., Ealick, S.E. and Begley, T.P. A missing enzyme in thiamin thiazole biosynthesis: identification of TenI as a thiazole tautomerase. J. Am. Chem. Soc. 133 (2011) 9311–9319. [DOI] [PMID: 21534620]

[EC 5.3.99.10 created 2012]

*EC

5.5.1.8

Accepted name:

(+)-bornyl diphosphate synthase

Reaction:

geranyl diphosphate = (+)-bornyl diphosphate

For diagram of bornane and related monoterpenoids, click here

Glossary:

(+)-bornyl diphosphate = (1R,2S,4R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-yl diphosphate

Other name(s):

bornyl pyrophosphate synthase (ambiguous); bornyl pyrophosphate synthetase (ambiguous); (+)-bornylpyrophosphate cyclase; geranyl-diphosphate cyclase (ambiguous); (+)-bornyl-diphosphate lyase (decyclizing)

Systematic name:

(+)-bornyl-diphosphate lyase (ring-opening)

Comments:

Requires Mg²⁺. The enzyme from Salvia officinalis (sage) can also use (3R)-linalyl diphosphate or more slowly neryl diphosphate in vitro [3]. The reaction proceeds via isomeration of geranyl diphosphate to (3R)-linalyl diphosphate. The oxygen and phosphorus originally linked to C-1 of geranyl diphosphate end up linked to C-2 of (+)-bornyl diphosphate [3]. cf. EC 5.5.1.22 [(–)-bornyl diphosphate synthase].

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, PDB, CAS registry number: 72668-91-8

References:

1.	Croteau, R. and Karp, F. Biosynthesis of monoterpenes: preliminary characterization of bornyl pyrophosphate synthetase from sage (Salvia officinalis) and demonstration that geranyl pyrophosphate is the preferred substrate for cyclization. Arch. Biochem. Biophys. 198 (1979) 512–522. [DOI] [PMID: 42356]
2.	Croteau, R., Gershenzon, J., Wheeler, C.J. and Satterwhite, D.M. Biosynthesis of monoterpenes: stereochemistry of the coupled isomerization and cyclization of geranyl pyrophosphate to camphane and isocamphane monoterpenes. Arch. Biochem. Biophys. 277 (1990) 374–381. [DOI] [PMID: 2178556]
3.	Croteau, R., Satterwhite, D.M., Cane, D.E. and Chang, C.C. Biosynthesis of monoterpenes. Enantioselectivity in the enzymatic cyclization of (+)- and (-)-linalyl pyrophosphate to (+)- and (-)-bornyl pyrophosphate. J. Biol. Chem. 261 (1986) 13438–13445. [PMID: 3759972]
4.	Croteau, R., Felton, N.M. and Wheeler, C.J. Stereochemistry at C-1 of geranyl pyrophosphate and neryl pyrophosphate in the cyclization to (+)- and (-)-bornyl pyrophosphate. J. Biol. Chem. 260 (1985) 5956–5962. [PMID: 3997807]
5.	Croteau, R.B., Shaskus, J.J., Renstrom, B., Felton, N.M., Cane, D.E., Saito, A. and Chang, C. Mechanism of the pyrophosphate migration in the enzymatic cyclization of geranyl and linalyl pyrophosphates to (+)- and (-)-bornyl pyrophosphates. Biochemistry 24 (1985) 7077–7085. [PMID: 4084562]
6.	McGeady, P. and Croteau, R. Isolation and characterization of an active-site peptide from a monoterpene cyclase labeled with a mechanism-based inhibitor. Arch. Biochem. Biophys. 317 (1995) 149–155. [DOI] [PMID: 7872777]
7.	Wise, M.L., Savage, T.J., Katahira, E. and Croteau, R. Monoterpene synthases from common sage (Salvia officinalis). cDNA isolation, characterization, and functional expression of (+)-sabinene synthase, 1,8-cineole synthase, and (+)-bornyl diphosphate synthase. J. Biol. Chem. 273 (1998) 14891–14899. [DOI] [PMID: 9614092]
8.	Whittington, D.A., Wise, M.L., Urbansky, M., Coates, R.M., Croteau, R.B. and Christianson, D.W. Bornyl diphosphate synthase: structure and strategy for carbocation manipulation by a terpenoid cyclase. Proc. Natl. Acad. Sci. USA 99 (2002) 15375–15380. [DOI] [PMID: 12432096]
9.	Peters, R.J. and Croteau, R.B. Alternative termination chemistries utilized by monoterpene cyclases: chimeric analysis of bornyl diphosphate, 1,8-cineole, and sabinene synthases. Arch. Biochem. Biophys. 417 (2003) 203–211. [DOI] [PMID: 12941302]

[EC 5.5.1.8 created 1984, modified 2012]

5.5.1.22

Accepted name:

(–)-bornyl diphosphate synthase

Reaction:

geranyl diphosphate = (–)-bornyl diphosphate

For diagram of bornane and related monoterpenoids, click here

Glossary:

(–)-bornyl diphosphate = (2R,4S)-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl diphosphate

Other name(s):

bornyl pyrophosphate synthase (ambiguous); bornyl pyrophosphate synthetase (ambiguous); (–)-bornyl pyrophosphate cyclase; bornyl diphosphate synthase; geranyl-diphosphate cyclase (ambiguous); (–)-bornyl-diphosphate lyase (decyclizing)

Systematic name:

(–)-bornyl-diphosphate lyase (ring-opening)

Comments:

Requires Mg²⁺. The enzyme from Tanacetum vulgare (tansy) can also use (3S)-linalyl diphosphate or more slowly neryl diphosphate in vitro. The reaction proceeds via isomeration of geranyl diphosphate to (3S)-linalyl diphosphate [3]. The oxygen and phosphorus originally linked to C-1 of geranyl diphosphate end up linked to C-2 of (–)-bornyl diphosphate [4]. cf. EC 5.5.1.8 (+)-bornyl diphosphate synthase.

Links to other databases:

BRENDA, EXPASY, KEGG, CAS registry number: 110639-17-3

References:

1.	Croteau, R., Gershenzon, J., Wheeler, C.J. and Satterwhite, D.M. Biosynthesis of monoterpenes: stereochemistry of the coupled isomerization and cyclization of geranyl pyrophosphate to camphane and isocamphane monoterpenes. Arch. Biochem. Biophys. 277 (1990) 374–381. [DOI] [PMID: 2178556]
2.	Croteau, R. and Shaskus, J. Biosynthesis of monoterpenes: demonstration of a geranyl pyrophosphate:(-)-bornyl pyrophosphate cyclase in soluble enzyme preparations from tansy (Tanacetum vulgare). Arch. Biochem. Biophys. 236 (1985) 535–543. [DOI] [PMID: 3970524]
3.	Croteau, R., Felton, N.M. and Wheeler, C.J. Stereochemistry at C-1 of geranyl pyrophosphate and neryl pyrophosphate in the cyclization to (+)- and (-)-bornyl pyrophosphate. J. Biol. Chem. 260 (1985) 5956–5962. [PMID: 3997807]
4.	Croteau, R.B., Shaskus, J.J., Renstrom, B., Felton, N.M., Cane, D.E., Saito, A. and Chang, C. Mechanism of the pyrophosphate migration in the enzymatic cyclization of geranyl and linalyl pyrophosphates to (+)- and (-)-bornyl pyrophosphates. Biochemistry 24 (1985) 7077–7085. [PMID: 4084562]
5.	Adam, K.P. and Croteau, R. Monoterpene biosynthesis in the liverwort Conocephalum conicum: demonstration of sabinene synthase and bornyl diphosphate synthase. Phytochemistry 49 (1998) 475–480. [DOI] [PMID: 9747540]

[EC 5.5.1.22 created 2012]

6.3.4.20

Accepted name:

7-cyano-7-deazaguanine synthase

Reaction:

7-carboxy-7-carbaguanine + NH₃ + ATP = 7-cyano-7-carbaguanine + ADP + phosphate + H₂O

For diagram of queuine biosynthesis, click here

Glossary:

preQ₀ = 7-cyano-7-carbaguanine = 7-cyano-7-deazaguanine
7-carboxy-7-carbaguanine = 7-carboxy-7-deazaguanine

Other name(s):

preQ₀ synthase; 7-cyano-7-carbaguanine synthase; queC (gene name)

Systematic name:

7-carboxy-7-carbaguanine:ammonia ligase (ADP-forming)

Comments:

Binds Zn²⁺. The reaction is part of the biosynthesis pathway of queuosine.

Links to other databases: