An asterisk before 'EC' indicates that this is an amendment to an existing enzyme rather than a new enzyme entry.
See also entries in separate files for EC 1, EC 2 and EC 3.
Common name: phosphoribosylaminoimidazole carboxylase
Reaction: 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate = 5-amino-1-(5-phospho-D-ribosyl)imidazole + CO2
For diagram, click here
Other name(s): 5-phosphoribosyl-5-aminoimidazole carboxylase; 5-amino-1-ribosylimidazole 5-phosphate carboxylase; AIR carboxylase; 1-(5-phosphoribosyl)-5-amino-4-imidazolecarboxylate carboxy-lyase; ADE2
Systematic name: 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate carboxy-lyase
Comments: While this is the reaction that occurs in vertebrates during purine biosynthesis, two enzymes are required to carry out the same reaction in Escherichia coli, namely EC 6.3.4.18, 5-(carboxyamino)imidazole ribonucleotide synthase and EC 5.4.99.18, 5-(carboxyamino)imidazole ribonucleotide mutase [3]. 5-Carboxyamino-1-(5-phospho-D-ribosyl)imidazole is not a substrate.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, PDB, CAS registry number: 9032-04-6
References:
1. Lukens, L.N. and Buchanan, J.M. Biosynthesis of purines. XXIV. The enzymatic synthesis of 5-amino-1-ribosyl-4-imidazolecarboxylic acid 5'-phosphate from 5-amino-1-ribosylimidazole 5'-phosphate and carbon dioxide. J. Biol. Chem. 234 (1959) 1799-1805. [PMID: 13672967]
2. Firestine, S.M., Poon, S.W., Mueller, E.J., Stubbe, J. and Davisson, V.J. Reactions catalyzed by 5-aminoimidazole ribonucleotide carboxylases from Escherichia coli and Gallus gallus: a case for divergent catalytic mechanisms. Biochemistry 33 (1994) 11927-11934. [PMID: 7918411]
3. Firestine, S.M., Misialek, S., Toffaletti, D.L., Klem, T.J., Perfect, J.R. and Davisson, V.J. Biochemical role of the Cryptococcus neoformans ADE2 protein in fungal de novo purine biosynthesis. Arch. Biochem. Biophys. 351 (1998) 123-134. [PMID: 9500840]
Common name: diaminobutyrate decarboxylase
Reaction: L-2,4-diaminobutanoate = propane-1,3-diamine + CO2
For diagram, click here
Other name(s): DABA DC; L-2,4-diaminobutyrate decarboxylase
Systematic name: L-2,4-diaminobutanoate carboxy-lyase
Comments: A pyridoxal-phosphate protein that requires a divalent cation for activity [1]. N4-Acetyl-L-2,4-diaminobutanoate, 2,3-diaminopropanoate, ornithine and lysine are not substrates. Found in the proteobacteria Haemophilus influenzae and Acinetobacter baumannii. In the latter, it is a product of the ddc gene that also encodes EC 2.6.1.76, diaminobutyrate—2-oxoglutarate transaminase, which can supply the substrate for the decarboxylase.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1.Yamamoto, S., Tsuzaki, Y., Tougou, K. and Shinoda, S. Purification and characterization of L-2,4-diaminobutyrate decarboxylase from Acinetobacter calcoaceticus. J. Gen. Microbiol. 138 (1992) 1461-1465. [PMID: 1512577]
2. Ikai, H. and Yamamoto, S. Cloning and expression in Escherichia coli of the gene encoding a novel L-2,4-diaminobutyrate decarboxylase of Acinetobacter baumannii. FEMS Microbiol. Lett. 124 (1994) 225-228. [PMID: 7813892]
3. Ikai, H. and Yamamoto, S. Identification and analysis of a gene encoding L-2,4-diaminobutyrate:2-ketoglutarate 4-aminotransferase involved in the 1,3-diaminopropane production pathway in Acinetobacter baumannii. J. Bacteriol. 179 (1997) 5118-5125. [PMID: 9260954]
Common name: indole-3-glycerol-phosphate lyase
Reaction: (1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate = indole + D-glyceraldehyde 3-phosphate
Other name(s): tryptophan synthase α; TSA; indoleglycerolphosphate aldolase; indole glycerol phosphate hydrolase; indole synthase; indole-3-glycerolphosphate D-glyceraldehyde-3-phosphate-lyase; indole-3-glycerol phosphate lyase; IGL; BX1
Systematic name: (1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate D-glyceraldehyde-3-phosphate-lyase
Comments: Forms part of the defence mechanism against insects and microbial pathogens in the grass family, Gramineae, where it catalyses one of the steps in the formation of the cyclic hydroxamic acids 2,4-dihydroxy-2H-1,4-benzoxazin-3(4H)-one (DIBOA) and 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA) [1]. This enzyme resembles the α-subunit of EC 4.2.1.20, tryptophan synthase [3] but, unlike tryptophan synthase, its activity is independent of the β-subunit and free indole is released [2].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Yanofsky, C. The enzymatic conversion of anthranilic acid to indole. J. Biol. Chem. 223 (1956) 171-184. [PMID: 13376586]
2. Frey, M., Chomet, P., Glawischnig, E., Stettner, C., Grün, S., Winklmair, A., Eisenreich, W., Bacher, A., Meeley, R.B., Briggs, S.P., Simcox, K. and Gierl, A. Analysis of a chemical plant defense mechanism in grasses. Science 277 (1997) 696-699.
3. Frey, M., Stettner, C., Paré, P.W., Schmelz, E.A., Tumlinson, J.H. and Gierl, A. An herbivore elicitor activates the gene for indole emission in maize. Proc. Natl. Acad. Sci. USA 97 (2000) 14801-14806. [PMID: 11106389]
4. Melanson, D., Chilton, M.D., Masters-Moore, D. and Chilton, W.S. A deletion in an indole synthase gene is responsible for the DIMBOA-deficient phenotype of bxbx maize. Proc. Natl. Acad. Sci. USA 94 (1997) 13345-13350. [PMID: 9371848]
Common name: 4-hydroxy-2-oxovalerate aldolase
Reaction: 4-hydroxy-2-oxovalerate = pyruvate + acetaldehyde
Other name(s): 4-hydroxy-2-ketovalerate aldolase; HOA; DmpG
Systematic name: 4-hydroxy-2-oxovalerate pyruvate-lyase
Comments: Requires Mn2+ for maximal activity [1]. The enzyme from Pseudomonas putida is also stimulated by the presence of NADH [1]. In Pseudomonas species, this enzyme forms part of a bifunctional enzyme with EC 1.2.1.10, acetaldehyde dehydrogenase (acetylating). It catalyses the penultimate step in the meta-cleavage pathway for the degradation of phenols, cresols and catechol [1].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Manjasetty, B.A., Powlowski, J. and Vrielink, A. Crystal structure of a bifunctional aldolase-dehydrogenase: sequestering a reactive and volatile intermediate. Proc. Natl. Acad. Sci. USA 100 (2003) 6992-6997. [PMID: 12764229]
2. Powlowski, J., Sahlman, L. and Shingler, V. Purification and properties of the physically associated meta-cleavage pathway enzymes 4-hydroxy-2-ketovalerate aldolase and aldehyde dehydrogenase (acylating) from Pseudomonas sp. strain CF600. J. Bacteriol. 175 (1993) 377-385. [PMID: 8419288]
3. Manjasetty, B.A., Croteau, N., Powlowski, J. and Vrielink, A. Crystallization and preliminary X-ray analysis of dmpFG-encoded 4-hydroxy-2-ketovalerate aldolase—aldehyde dehydrogenase (acylating) from Pseudomonas sp. strain CF600. Acta Crystallogr. D Biol. Crystallogr. 57 (2001) 582-585. [PMID: 11264589]
Common name: 3-hydroxydecanoyl-[acyl-carrier-protein] dehydratase
Reaction: (1) (3R)-3-hydroxydecanoyl-[acyl-carrier-protein] = trans-dec-2-enoyl-[acyl-carrier-protein] + H2O
(2) (3R)-3-hydroxydecanoyl-[acyl-carrier-protein] = cis-dec-3-enoyl-[acyl-carrier-protein] + H2O
Other name(s): D-3-hydroxydecanoyl-[acyl-carrier protein] dehydratase; 3-hydroxydecanoyl-acyl carrier protein dehydrase; 3-hydroxydecanoyl-acyl carrier protein dehydratase; β-hydroxydecanoyl thioester dehydrase; β-hydroxydecanoate dehydrase; β-hydroxydecanoyl thiol ester dehydrase; FabA; β-hydroxyacyl-acyl carrier protein dehydratase; HDDase; β-hydroxyacyl-ACP dehydrase
Systematic name: (3R)-3-hydroxydecanoyl-[acyl-carrier-protein] hydro-lyase
Comments: Specific for C10 chain length.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, PDB, CAS registry number: 9030-79-9
References:
1. Kass, L.R., Brock, D.J. and Bloch, K. β-Hydroxydecanoyl thioester dehydrase. I. Purification and properties. J. Biol. Chem. 242 (1967) 4418-4431. [PMID: 4863739]
2. Brock, D.J.H., Kass, L.R. and Bloch, K. β-Hydroxydecanoyl thioester dehydrase. II. Mode of action. J. Biol. Chem. 242 (1967) 4432-4440. [PMID: 4863740]
3. Sharma, A., Henderson, B.S., Schwab, J.M. and Smith, J.L. Crystallization and preliminary X-ray analysis of β-hydroxydecanoyl thiol ester dehydrase from Escherichia coli. J. Biol. Chem. 265 (1990) 5110-5112. [PMID: 2180957]
4. Magnuson, K., Jackowski, S., Rock, C.O. and Cronan, J.E., Jr. Regulation of fatty acid biosynthesis in Escherichia coli. Microbiol. Rev. 57 (1993) 522-542. [PMID: 8246839]
5. Bloch, K. Enzymatic synthesis of monounsaturated fatty acids. Acc. Chem. Res. 2 (1969) 193-202.
6. Wang, H. and Cronan, J.E. Functional replacement of the FabA and FabB proteins of Escherichia coli fatty acid synthesis by Enterococcus faecalis FabZ and FabF homologues. J. Biol. Chem. 279 (2004) 34489-34495. [PMID: 15194690]
7. Cronan, J.E., Jr. and Rock, C.O. Biosynthesis of membrane lipids. In: Neidhardt, F.C. (Ed.), Escherichia coli and Salmonella: Cellular and Molecular Biology, 2nd edn, vol. 1, ASM Press, Washington, DC, 1996, pp. 612-636.
Common name: ectoine synthase
Reaction: N4-acetyl-L-2,4-diaminobutanoate = L-ectoine + H2O
For diagram, click here
Glossary: ectoine = (4S)-2-methyl-1,4,5,6-tetrahydropyrimidine-4-carboxylate
Other name(s): N-acetyldiaminobutyrate dehydratase; N-acetyldiaminobutanoate dehydratase; L-ectoine synthase; EctC
Systematic name: N4-acetyl-L-2,4-diaminobutanoate hydro-lyase
Comments: Ectoine is an osmoprotectant that is found in halophilic eubacteria. This is the third enzyme in the ectoine-biosynthesis pathway, the other enzymes involved being EC 2.6.1.76, diaminobutyrate—2-oxoglutarate transaminase and EC 2.3.1.178, diaminobutyrate acetyltransferase [1,2].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Peters, P., Galinski, E.A. and Truper, H.G. The biosynthesis of ectoine. FEMS Microbiol. Lett. 71 (1990) 157-162.
2. Ono, H., Sawada, K., Khunajakr, N., Tao, T., Yamamoto, M., Hiramoto, M., Shinmyo, A., Takano, M. and Murooka, Y. Characterization of biosynthetic enzymes for ectoine as a compatible solute in a moderately halophilic eubacterium, Halomonas elongata. J. Bacteriol. 181 (1999) 91-99. [PMID: 9864317]
3. Kuhlmann, A.U. and Bremer, E. Osmotically regulated synthesis of the compatible solute ectoine in Bacillus pasteurii and related Bacillus spp. Appl. Environ. Microbiol. 68 (2002) 772-783. [PMID: 11823218]
4. Louis, P. and Galinski, E.A. Characterization of genes for the biosynthesis of the compatible solute ectoine from Marinococcus halophilus and osmoregulated expression in Escherichia coli. Microbiology 143 (1997) 1141-1149. [PMID: 9141677]
Common name: aristolochene synthase
Reaction: (1) 2-trans,6-trans-farnesyl diphosphate = aristolochene + diphosphate
(2) 2-trans,6-trans-farnesyl diphosphate = (+)-(10R)-germacrene A + diphosphate
For diagram, click here
Other name(s): sesquiterpene cyclase; trans,trans-farnesyl diphosphate aristolochene-lyase; trans,trans-farnesyl-diphosphate diphosphate-lyase (cyclizing, aristolochene-forming)
Systematic name: 2-trans,6-trans-farnesyl-diphosphate diphosphate-lyase (cyclizing, aristolochene-forming)
Comments: The initial internal cyclization produces the monocyclic intermediate germacrene A; further cyclization and methyl transfer converts the intermediate into aristolochene. While in some species germacrene A remains as an enzyme-bound intermediate, it has been shown to be a minor product of the reaction in Penicillium roqueforti [5] (see also EC 4.2.3.23, germacrene-A synthase). The enzyme from Penicillium roqueforti requires Mg2+ and Mn2+ for activity. Aristolochene is the likely parent compound for a number of sesquiterpenes produced by filamentous fungi.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Cane, D.E., Prabhakaran, P.C., Oliver, J.S. and McIlwaine, D.B. Aristolochene biosynthesis. Stereochemistry of the deprotonation steps in the enzymatic cyclization of farnesyl pyrophosphate. J. Am. Chem. Soc. 112 (1990) 3209-3210.
2. Cane, D.E., Prabhakaran, P.C., Salaski, E.J., Harrison, P.M.H., Noguchi, H. and Rawlings, B.J. Aristolochene biosynthesis and enzymatic cyclization of farnesyl pyrophosphate. J. Am. Chem. Soc. 111 (1989) 8914-8916.
3. Hohn, T.M. and Plattner, R.D. Purification and characterization of the sesquiterpene cyclase aristolochene synthase from Penicillium roqueforti. Arch. Biochem. Biophys. 272 (1989) 137-143. [PMID: 2544140]
4. Proctor, R.H. and Hohn, T.M. Aristolochene synthase. Isolation, characterization, and bacterial expression of a sesquiterpenoid biosynthetic gene (Ari1) from Penicillium roqueforti. J. Biol. Chem. 268 (1993) 4543-4548. [PMID: 8440737]
5. Calvert, M.J., Ashton, P.R. and Allemann, R.K. Germacrene A is a product of the aristolochene synthase-mediated conversion of farnesylpyrophosphate to aristolochene. J. Am. Chem. Soc. 124 (2002) 11636-11641. [PMID: 12296728]
Common name: germacradienol synthase
Reaction: (1) 2-trans,6-trans-farnesyl diphosphate + H2O = (1E,4S,5E,7R)-germacra-1(10),5-dien-11-ol + diphosphate
(2) 2-trans,6-trans-farnesyl diphosphate = (-)-(7S)-germacrene D
Other name(s): germacradienol/germacrene-D synthase
Systematic name: 2-trans,6-trans-farnesyl-diphosphate diphosphate-lyase [(1E,4S,5E,7R)-germacra-1(10),5-dien-11-ol-forming]
Comments: Requires Mg2+ for activity. H-1si of farnesyl diphosphate is lost in the formation of (1E,4S,5E,7R)-germacra-1(10),5-dien-11-ol. Formation of (-)-germacrene D involves a stereospecific 1,3-hydride shift of H-1si of farnesyl diphosphate. Both products are formed from a common intermediate [2]. Other enzymes produce germacrene D as the sole product using a different mechanism. The enzyme mediates a key step in the biosynthesis of geosmin, a widely occurring metabolite of many streptomycetes, bacteria and fungi [2].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Cane, D.E. and Watt, R.M. Expression and mechanistic analysis of a germacradienol synthase from Streptomyces coelicolor implicated in geosmin biosynthesis. Proc. Natl. Acad. Sci. USA 100 (2003) 1547-1551. [PMID: 12556563]
2. He, X. and Cane, D.E. Mechanism and stereochemistry of the germacradienol/germacrene D synthase of Streptomyces coelicolor A3(2). J. Am. Chem. Soc. 126 (2004) 2678-2679. [PMID: 14995166]
3. Gust, B., Challis, G.L., Fowler, K., Kieser, T. and Chater, K.F. PCR-targeted Streptomyces gene replacement identifies a protein domain needed for biosynthesis of the sesquiterpene soil odor geosmin. Proc. Natl. Acad. Sci. USA 100 (2003) 1541-1546. [PMID: 12563033]
Common name: germacrene-A synthase
Reaction: 2-trans,6-trans-farnesyl diphosphate = (+)-(R)-germacrene A + diphosphate
Other name(s): germacrene A synthase; (+)-germacrene A synthase; (+)-(10R)-germacrene A synthase; GAS
Systematic name: 2-trans,6-trans-farnesyl-diphosphate diphosphate-lyase (germacrene-A-forming)
Comments: Requires Mg2+ for activity. While germacrene A is an enzyme-bound intermediate in the biosynthesis of a number of phytoalexins, e.g. EC 4.2.3.9 (aristolochene synthase) from some species and EC 4.2.3.21 (vetispiradiene synthase), it is the sole sesquiterpenoid product formed in chicory [1].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Bouwmeester, H.J., Kodde, J., Verstappen, F.W., Altug, I.G., de Kraker, J.W. and Wallaart, T.E. Isolation and characterization of two germacrene A synthase cDNA clones from chicory. Plant Physiol. 129 (2002) 134-144. [PMID: 12011345]
2. Prosser, I., Phillips, A.L., Gittings, S., Lewis, M.J., Hooper, A.M., Pickett, J.A. and Beale, M.H. (+)-(10R)-Germacrene A synthase from goldenrod, Solidago canadensis; cDNA isolation, bacterial expression and functional analysis. Phytochemistry 60 (2002) 691-702. [PMID: 12127586]
3. de Kraker, J.W., Franssen, M.C., de Groot, A., Konig, W.A. and Bouwmeester, H.J. (+)-Germacrene A biosynthesis . The committed step in the biosynthesis of bitter sesquiterpene lactones in chicory. Plant Physiol. 117 (1998) 1381-1392. [PMID: 9701594]
4. Calvert, M.J., Ashton, P.R. and Allemann, R.K. Germacrene A is a product of the aristolochene synthase-mediated conversion of farnesylpyrophosphate to aristolochene. J. Am. Chem. Soc. 124 (2002) 11636-11641. [PMID: 12296728]
5. Chang, Y.J., Jin, J., Nam, H.Y. and Kim, S.U. Point mutation of (+)-germacrene A synthase from Ixeris dentata. Biotechnol. Lett. 27 (2005) 285-288. [PMID: 15834787]
Common name: amorpha-4,11-diene synthase
Reaction: 2-trans,6-trans-farnesyl diphosphate = amorpha-4,11-diene + diphosphate
Other name(s): amorphadiene synthase
Systematic name: 2-trans,6-trans-farnesyl-diphosphate diphosphate-lyase (amorpha-4,11-diene-forming)
Comments: Requires Mg2+ and Mn2+ for activity. This is a key enzyme in the biosynthesis of the antimalarial endoperoxide artemisinin [3]. Catalyses the formation of both olefinic [e.g. amorpha-4,11-diene, amorpha-4,7(11)-diene, γ-humulene and β-sesquiphellandrene] and oxygenated (e.g. amorpha-4-en-7-ol) sesquiterpenes, with amorpha-4,11-diene being the major product. When geranyl diphosphate is used as a substrate, no monoterpenes are produced [2].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Wallaart, T.E., Bouwmeester, H.J., Hille, J., Poppinga, L. and Maijers, N.C. Amorpha-4,11-diene synthase: cloning and functional expression of a key enzyme in the biosynthetic pathway of the novel antimalarial drug artemisinin. Planta 212 (2001) 460-465. [PMID: 11289612]
2. Mercke, P., Bengtsson, M., Bouwmeester, H.J., Posthumus, M.A. and Brodelius, P.E. Molecular cloning, expression, and characterization of amorpha-4,11-diene synthase, a key enzyme of artemisinin biosynthesis in Artemisia annua L. Arch. Biochem. Biophys. 381 (2000) 173-180. [PMID: 11032404]
3. Bouwmeester, H.J., Wallaart, T.E., Janssen, M.H., van Loo, B., Jansen, B.J., Posthumus, M.A., Schmidt, C.O., De Kraker, J.W., Konig, W.A. and Franssen, M.C. Amorpha-4,11-diene synthase catalyses the first probable step in artemisinin biosynthesis. Phytochemistry 52 (1999) 843-854. [PMID: 10626375]
4. Chang, Y.J., Song, S.H., Park, S.H. and Kim, S.U. Amorpha-4,11-diene synthase of Artemisia annua: cDNA isolation and bacterial expression of a terpene synthase involved in artemisinin biosynthesis. Arch. Biochem. Biophys. 383 (2000) 178-184. [PMID: 11185551]
5. Martin, V.J., Pitera, D.J., Withers, S.T., Newman, J.D. and Keasling, J.D. Engineering a mevalonate pathway in Escherichia coli for production of terpenoids. Nat. Biotechnol. 21 (2003) 796-802. [PMID: 12778056]
6. Picaud, S., Mercke, P., He, X., Sterner, O., Brodelius, M., Cane, D.E. and Brodelius, P.E. Amorpha-4,11-diene synthase: Mechanism and stereochemistry of the enzymatic cyclization of farnesyl diphosphate. Arch. Biochem. Biophys. 448 (2006) 150-155. [PMID: 16143293]
Common name: S-linalool synthase
Reaction: geranyl diphosphate + H2O = (3S)-linalool + diphosphate
Glossary: (3S)-linalool = (3S)-3,7-dimethylocta-1,6-dien-3-ol
Other name(s): LIS; Lis; 3S-linalool synthase
Systematic name: geranyl-diphosphate diphosphate-lyase [(3S)-linalool-forming]
Comments: Requires Mn2+ or Mg2+ for activity. Neither (3S)- nor (3R)-linalyl diphosphate can act as substrate for the enzyme from the flower Clarkia breweri [1]. Unlike many other monoterpene synthases, only a single product, (3S)-linalool, is formed.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Pichersky, E., Lewinsohn, E. and Croteau, R. Purification and characterization of S-linalool synthase, an enzyme involved in the production of floral scent in Clarkia breweri. Arch. Biochem. Biophys. 316 (1995) 803-807. [PMID: 7864636]
2. Lucker, J., Bouwmeester, H.J., Schwab, W., Blaas, J., van der Plas, L.H. and Verhoeven, H.A. Expression of Clarkia S-linalool synthase in transgenic petunia plants results in the accumulation of S-linalyl-β-D-glucopyranoside. Plant J. 27 (2001) 315-324. [PMID: 11532177]
3. Dudareva, N., Cseke, L., Blanc, V.M. and Pichersky, E. Evolution of floral scent in Clarkia: novel patterns of S-linalool synthase gene expression in the C. breweri flower. Plant Cell 8 (1996) 1137-1148. [PMID: 8768373]
Common name: R-linalool synthase
Reaction: geranyl diphosphate + H2O = (3R)-linalool + diphosphate
Glossary: (3R)-linalool = (3R)-3,7-dimethylocta-1,6-dien-3-ol
Other name(s): (3R)-linalool synthase; (-)-3R-linalool synthase
Systematic name: geranyl-diphosphate diphosphate-lyase [(3R)-linalool-forming]
Comments: Geranyl diphosphate cannot be replaced by isopentenyl diphosphate, dimethylallyl diphosphate, farnesyl diphosphate or geranylgeranyl diphosphate as substrate [1]. Requires Mg2+ or Mn2+ for activity. Unlike many other monoterpene synthases, only a single product, (3R)-linalool, is formed.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Jia, J.W., Crock, J., Lu, S., Croteau, R. and Chen, X.Y. (3R)-Linalool synthase from Artemisia annua L.: cDNA isolation, characterization, and wound induction. Arch. Biochem. Biophys. 372 (1999) 143-149. [PMID: 10562427]
2. Crowell, A.L., Williams, D.C., Davis, E.M., Wildung, M.R. and Croteau, R. Molecular cloning and characterization of a new linalool synthase. Arch. Biochem. Biophys. 405 (2002) 112-121. [PMID: 12176064]
Common name: sulfolactate sulfo-lyase
Reaction: 3-sulfolactate = pyruvate + bisulfite
Other name(s): Suy; SuyAB
Systematic name: 3-sulfolactate bisulfite-lyase
Comments: Requires iron(II). This inducible enzyme from Paracoccus pantotrophus NKNCYSA forms part of the cysteate-degradation pathway. L-Cysteate [(2S)-2-amino-3-sulfopropanoate] serves as a sole source of carbon and energy for the aerobic growth of bacteria, as an electron acceptor for several sulfate-reducing bacteria, as an electron donor for some nitrate-reducing bacteria and as a substrate for a fermentation in a sulfate-reducing baterium.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Rein, U., Gueta, R., Denger, K., Ruff, J., Hollemeyer, K. and Cook, A.M. Dissimilation of cysteate via 3-sulfolactate sulfo-lyase and a sulfate exporter in Paracoccus pantotrophus NKNCYSA. Microbiology 151 (2005) 737-747. [PMID: 15758220]
Common name: L-cysteate sulfo-lyase
Reaction: L-cysteate + H2O = pyruvate + bisulfite + NH3
Glossary: L-cysteate = (2S)-2-amino-3-sulfopropanoate
Other name(s): L-cysteate sulfo-lyase (deaminating); CuyA
Systematic name: L-cysteate bisulfite-lyase (deaminating)
Comments: A pyridoxal-phosphate protein. D-Cysteine can also act as a substrate, but more slowly. It is converted into pyruvate, sulfide and NH3. This inducible enzyme from the marine bacterium Silicibacter pomeroyi DSS-3 forms part of the cysteate-degradation pathway.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Denger, K., Smits, T.H. and Cook, A.M. L-cysteate sulpho-lyase, a widespread, pyridoxal 5'-phosphate-coupled desulphonative enzyme purified from Silicibacter pomeroyi DSS-3 T. Biochem. J. 394 (2005) 657-664. [PMID: 16302849]
Common name: trans-2-decenoyl-[acyl-carrier protein] isomerase
Reaction: trans-dec-2-enoyl-[acyl-carrier-protein] = cis-dec-3-enoyl-[acyl-carrier-protein]
Other name(s): β-hydroxydecanoyl thioester dehydrase; trans-2-cis-3-decenoyl-ACP isomerase; trans-2,cis-3-decenoyl-ACP isomerase; trans-2-decenoyl-ACP isomerase; FabM
Systematic name: decenoyl-[acyl-carrier-protein] Δ2-trans-Δ3-cis-isomerase
Comments: While the enzyme from Escherichia coli is highly specific for the 10-carbon enoyl-ACP, the enzyme from Streptococcus pneumoniae can also use the 12-carbon enoyl-ACP as substrate in vitro but not 14- or 16-carbon enoyl-ACPs [3]. ACP can be replaced by either CoA or N-acetylcysteamine thioesters. The cis-3-enoyl product is required to form unsaturated fatty acids, such as palmitoleic acid and cis-vaccenic acid, in dissociated (or type II) fatty-acid biosynthesis.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Brock, D.J.H., Kass, L.R. and Bloch, K. β-Hydroxydecanoyl thioester dehydrase. II. Mode of action. J. Biol. Chem. 242 (1967) 4432-4440. [PMID: 4863740]
2. Bloch, K. Enzymatic synthesis of monounsaturated fatty acids. Acc. Chem. Res. 2 (1969) 193-202.
3. Marrakchi, H., Choi, K.H. and Rock, C.O. A new mechanism for anaerobic unsaturated fatty acid formation in Streptococcus pneumoniae. J. Biol. Chem. 277 (2002) 44809-44816. [PMID: 12237320]
4. Cronan, J.E., Jr. and Rock, C.O. Biosynthesis of membrane lipids. In: Neidhardt, F.C. (Ed.), Escherichia coli and Salmonella: Cellular and Molecular Biology, 2nd edn, vol. 1, ASM Press, Washington, DC, 1996, pp. 612-636.
Common name: 5-(carboxyamino)imidazole ribonucleotide mutase
Reaction: 5-carboxyamino-1-(5-phospho-D-ribosyl)imidazole = 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate
For diagram, click here
Other name(s): N5-CAIR mutase; PurE; N5-carboxyaminoimidazole ribonucleotide mutase
Systematic name: 5-carboxyamino-1-(5-phospho-D-ribosyl)imidazole carboxymutase
Comments: In Escherichia coli, this enzyme, along with EC 6.3.4.18, 5-(carboxyamino)imidazole ribonucleotide synthase, is required to carry out the single reaction catalysed by EC 4.1.1.21, phosphoribosylaminoimidazole carboxylase, in vertebrates. In the absence of EC 6.3.2.6, phosphoribosylaminoimidazolesuccinocarboxamide synthase, the reaction is reversible [3]. The substrate is readily converted into 5-amino-1-(5-phospho-D-ribosyl)imidazole by non-enzymic decarboxylation [3].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Meyer, E., Leonard, N.J., Bhat, B., Stubbe, J. and Smith, J.M. Purification and characterization of the purE, purK, and purC gene products: identification of a previously unrecognized energy requirement in the purine biosynthetic pathway. Biochemistry 31 (1992) 5022-5032. [PMID: 1534690]
2. Mueller, E.J., Meyer, E., Rudolph, J., Davisson, V.J. and Stubbe, J. N5-Carboxyaminoimidazole ribonucleotide: evidence for a new intermediate and two new enzymatic activities in the de novo purine biosynthetic pathway of Escherichia coli. Biochemistry 33 (1994) 2269-2278. [PMID: 8117684]
3. Meyer, E., Kappock, T.J., Osuji, C. and Stubbe, J. Evidence for the direct transfer of the carboxylate of N5-carboxyaminoimidazole ribonucleotide (N5-CAIR) to generate 4-carboxy-5-aminoimidazole ribonucleotide catalyzed by Escherichia coli PurE, an N5-CAIR mutase. Biochemistry 38 (1999) 3012-3018. [PMID: 10074353]
4. Mathews, I.I., Kappock, T.J., Stubbe, J. and Ealick, S.E. Crystal structure of Escherichia coli PurE, an unusual mutase in the purine biosynthetic pathway. Structure 7 (1999) 1395-1406. [PMID: 10574791]
Common name: phosphoribosylaminoimidazolesuccinocarboxamide synthase
Reaction: ATP + 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate + L-aspartate = ADP + phosphate + (S)-2-[5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxamido]succinate
For diagram, click here
Other name(s): phosphoribosylaminoimidazole-succinocarboxamide synthetase; PurC; SAICAR synthetase; 4-(N-succinocarboxamide)-5-aminoimidazole synthetase; 4-[(N-succinylamino)carbonyl]-5-aminoimidazole ribonucleotide synthetase; SAICARs; 5-aminoimidazole-4-N-succinocarboxamide ribonucleotide synthetase; phosphoribosylaminoimidazolesuccinocarboxamide synthetase; 5-aminoimidazole-4-N-succinocarboxamide ribonucleotide synthetase
Systematic name: 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate:L-aspartate ligase (ADP-forming)
Comments: Forms part of the purine biosynthesis pathway.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, PDB, CAS registry number: 9023-67-0
References:
1. Lukens, L.N. and Buchanan, J.M. Biosynthesis of purines. XXIV. The enzymatic synthesis of 5-amino-1-ribosyl-4-imidazolecarboxylic acid 5'-phosphate from 5-amino-1-ribosylimidazole 5'-phosphate and carbon dioxide. J. Biol. Chem. 234 (1959) 1799-1805. [PMID: 13672967]
2. Parker, J. Identification of the purC gene product of Escherichia coli. J. Bacteriol. 157 (1984) 712-717. [PMID: 6365889]
3. Ebbole, D.J. and Zalkin, H. Cloning and characterization of a 12-gene cluster from Bacillus subtilis encoding nine enzymes for de novo purine nucleotide synthesis. J. Biol. Chem. 262 (1987) 8274-8287. [PMID: 3036807]
4. Chen, Z.D., Dixon, J.E. and Zalkin, H. Cloning of a chicken liver cDNA encoding 5-aminoimidazole ribonucleotide carboxylase and 5-aminoimidazole-4-N-succinocarboxamide ribonucleotide synthetase by functional complementation of Escherichia coli pur mutants. Proc. Natl. Acad. Sci. USA 87 (1990) 3097-3101. [PMID: 1691501]
5. O'Donnell, A.F., Tiong, S., Nash, D. and Clark, D.V. The Drosophila melanogaster ade5 gene encodes a bifunctional enzyme for two steps in the de novo purine synthesis pathway. Genetics 154 (2000) 1239-1253. [PMID: 10757766]
6. Nelson, S.W., Binkowski, D.J., Honzatko, R.B. and Fromm, H.J. Mechanism of action of Escherichia coli phosphoribosylaminoimidazolesuccinocarboxamide synthetase. Biochemistry 44 (2005) 766-774. [PMID: 15641804]
Common name: aerobactin synthase
Reaction: 4 ATP + citrate + 2 N6-acetyl-N6-hydroxy-L-lysine + 2 H2O = 4 ADP + 4 phosphate + aerobactin
For diagram, click here
Systematic name: citrate:N6-acetyl-N6-hydroxy-L-lysine ligase (ADP-forming)
Comments: Requires Mg2+. Aerobactin is one of a group of high-affinity iron chelators known as siderophores and is produced under conditions of iron deprivation [5]. It is a dihydroxamate comprising two molecules of N6-acetyl-N6-hydroxylysine and one molecule of citric acid. This is the last of the three enzymes involved in its synthesis, the others being EC 1.14.13.59, L-lysine 6-monooxygenase (NADPH) and EC 2.3.1.102, N6-hydroxylysine O-acetyltransferase [3].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number: 94047-30-0
References:
1. Appanna, D.L., Grundy, B.J., Szczepan, E.W. and Viswanatha, T. Aerobactin synthesis in a cell-free system of Aerobacter aerogenes 62-1. Biochim. Biophys. Acta 801 (1984) 437-443.
2. Gibson, F. and Magrath, D.I. The isolation and characterization of a hydroxamic acid (aerobactin) formed by Aerobacter aerogenes 62-I. Biochim. Biophys. Acta 192 (1969) 175-184. [PMID: 4313071]
3. Maurer, P.J. and Miller, M. Microbial iron chelators: total synthesis of aerobactin and its constituent amino acid, N6-acetyl-N6-hydroxylysine. J. Am. Chem. Soc. 104 (1982) 3096-3101.
4. de Lorenzo, V., Bindereif, A., Paw, B.H. and Neilands, J.B. Aerobactin biosynthesis and transport genes of plasmid ColV-K30 in Escherichia coli K-12. J. Bacteriol. 165 (1986) 570-578. [PMID: 2935523]
5. Challis, G.L. A widely distributed bacterial pathway for siderophore biosynthesis independent of nonribosomal peptide synthetases. ChemBioChem 6 (2005) 601-611. [PMID: 15719346]
Common name: 5-(carboxyamino)imidazole ribonucleotide synthase
Reaction: ATP + 5-amino-1-(5-phospho-D-ribosyl)imidazole + HCO3- = ADP + phosphate + 5-carboxyamino-1-(5-phospho-D-ribosyl)imidazole
For diagram, click here
Other name(s): N5-CAIR synthetase; N5-carboxyaminoimidazole ribonucleotide synthetase; PurK
Systematic name: 5-amino-1-(5-phospho-D-ribosyl)imidazole:carbon-dioxide ligase (ADP-forming)
Comments: In Escherichia coli, this enzyme, along with EC 5.4.99.18, 5-(carboxyamino)imidazole ribonucleotide mutase, is required to carry out the single reaction catalysed by EC 4.1.1.21, phosphoribosylaminoimidazole carboxylase, in vertebrates. Belongs to the ATP grasp protein superfamily [3]. Carboxyphosphate is the putative acyl phosphate intermediate. Involved in the late stages of purine biosynthesis.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number:
References:
1. Meyer, E., Leonard, N.J., Bhat, B., Stubbe, J. and Smith, J.M. Purification and characterization of the purE, purK, and purC gene products: identification of a previously unrecognized energy requirement in the purine biosynthetic pathway. Biochemistry 31 (1992) 5022-5032. [PMID: 1534690]
2. Mueller, E.J., Meyer, E., Rudolph, J., Davisson, V.J. and Stubbe, J. N5-Carboxyaminoimidazole ribonucleotide: evidence for a new intermediate and two new enzymatic activities in the de novo purine biosynthetic pathway of Escherichia coli. Biochemistry 33 (1994) 2269-2278. [PMID: 8117684]
3. Thoden, J.B., Kappock, T.J., Stubbe, J. and Holden, H.M. Three-dimensional structure of N5-carboxyaminoimidazole ribonucleotide synthetase: a member of the ATP grasp protein superfamily. Biochemistry 38 (1999) 15480-15492. [PMID: 10569930]