EC 5.1.1 Acting on Amino Acids and Derivatives
EC 5.1.2 Acting on Hydroxy Acids and Derivatives
EC 5.1.3 Acting on Carbohydrates and Derivatives
EC 5.1.99 Acting on Other Compounds
Accepted name: alanine racemase
Reaction: L-alanine = D-alanine
Other name(s): L-alanine racemase
Systematic name: alanine racemase
Comments: A pyridoxal-phosphate protein.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, CAS registry number: 9024-06-0
References:
1. Marr, A.G. and Wilson, P.W. The alanine racemase of Brucella abortus. Arch. Biochem. Biophys. 49 (1954) 424-433.
2. Wood, W.A. Amino acid racemases. Methods Enzymol. 2 (1955) 212-217.
3. Wood, W.A. and Gunsalus, I.C. D-Alanine formation: a racemase in Streptococcus faecalis. J. Biol. Chem. 190 (1951) 403-416.
Accepted name: methionine racemase
Reaction: L-methionine = D-methionine
Systematic name: methionine racemase
Comments: A pyridoxal-phosphate protein.
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 9024-07-1
References:
1. Kallio, R.E. and Larson, A.D. Methionine degradation by a species of Pseudomonas, in McElroy, W.D. and Glass, H.B. (Eds.), A Symposium on Amino Acid Metabolism, Johns Hopkins Press, Baltimore, 1955, pp. 616-634.
Accepted name: glutamate racemase
Reaction: L-glutamate = D-glutamate
Systematic name: glutamate racemase
Comments: A pyridoxal-phosphate protein.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, CAS registry number: 9024-08-2
References:
1. Glaser, L. Glutamic acid racemase from Lactobacillus arabinosus. J. Biol. Chem. 235 (1960) 2095-2098.
Accepted name: proline racemase
Reaction: L-proline = D-proline
Systematic name: proline racemase
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 9024-09-3
References:
1. Stadtman, T.C. and Elliott, P. Studies on the enzymic reduction of amino acids. II. Purification and properties of a D-proline reductase and a proline racemase from Clostridium sticklandii. J. Biol. Chem. 228 (1957) 983-997.
Accepted name: lysine racemase
Reaction: L-lysine = D-lysine
Systematic name: lysine racemase
Links to other databases: BRENDA, EXPASY, GTD, KEGG, CAS registry number: 9024-10-6
References:
1. Huang, H.T. dl-Lysine production by lysine racemase. U.S. Pat. 2944943 [Chem. Abstr. 54 (1960) 20073].
Accepted name: threonine racemase
Reaction: L-threonine = D-threonine
Glossary: D-threonine = (2R,3S)-2-amino-3-hydroxybutanoic acid
Systematic name: threonine racemase
Comments: Inverts both chiral centres.
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 9024-11-7
References:
1. Amos, H. A racemase for threonine in Escherichia coli. J. Am. Chem. Soc. 76 (1954) 3858 only.
Accepted name: diaminopimelate epimerase
Reaction: LL-2,6-diaminoheptanedioate = meso-diaminoheptanedioate
For diagram click here.
Systematic name: LL-2,6-diaminoheptanedioate 2-epimerase
Links to other databases: BRENDA, EXPASY, GTD, KEGG, CAS registry number: 9024-22-0
References:
1. Antia, M., Hoare, D.S. and Work, W. The stereoisomers of αε-diaminopimelic acid. 3. Properties and distribution of diaminopimelic acid racemase, an enzyme causing interconversion of the LL and meso isomers. Biochem. J. 65 (1957) 448-459.
Accepted name: 4-hydroxyproline epimerase
Reaction: trans-4-hydroxy-L-proline = cis-4-hydroxy-D-proline
For reaction pathway click here.
Other name(s): hydroxyproline epimerase; hydroxyproline 2-epimerase; L-hydroxyproline epimerase
Systematic name: 4-hydroxyproline 2-epimerase
Comments: Also interconverts trans-4-hydroxy-D-proline and cis-4-hydroxy-L-proline.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, CAS registry number: 9024-23-1
References:
1. Adams, E. and Norton, I.L. Purification and properties of inducible hydroxyproline 2-epimerase from Pseudomonas. J. Biol. Chem. 239 (1964) 1525-1535.
Accepted name: arginine racemase
Reaction: L-arginine = D-arginine
Systematic name: arginine racemase
Comments: A pyridoxal-phosphate protein.
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 37290-94-1
References:
1. Yorifuji, T., Ogata, K. and Soda, K. Crystalline arginine racemase. Biochem. Biophys. Res. Commun. 34 (1969) 760-764. [PMID: 5779761]
Accepted name: amino-acid racemase
Reaction: An L-amino acid = a D-amino acid
Other name(s): L-amino acid racemase
Systematic name: amino-acid racemase
Comments: A pyridoxal-phosphate protein.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, CAS registry number: 9068-61-5
References:
1. Soda, K. and Osumi, T. Crystalline amino acid racemase with low substrate specificity. Biochem. Biophys. Res. Commun. 35 (1969) 363-368. [PMID: 5788493]
Accepted name: phenylalanine racemase (ATP-hydrolysing)
Reaction: ATP + L-phenylalanine + H2O = AMP + diphosphate + D-phenylalanine
Other name(s): phenylalanine racemase; phenylalanine racemase (adenosine triphosphate-hydrolysing); gramicidin S synthetase I
Systematic name: phenylalanine racemase (ATP-hydrolysing)
Links to other databases: BRENDA, EXPASY, KEGG, PDB, CAS registry number: 37290-95-2
References:
1. Yamada, M. and Kurahashi, K. Further purification and properties of adenosine triphosphate-dependent phenylalanine racemase of Bacillus brevis Nagano. J. Biochem. (Tokyo) 66 (1969) 529-540. [PMID: 5354026]
Accepted name: ornithine racemase
Reaction: L-ornithine = D-ornithine
Systematic name: ornithine racemase
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 62213-28-9
References:
1. Chen, H.P., Lin, C.F., Lee, Y.J., Tsay, S.S. and Wu, S.H. Purification and properties of ornithine racemase from Clostridium sticklandii. J. Bacteriol. 182 (2000) 2052-2054. [PMID: 10715017]
Accepted name: aspartate racemase
Reaction: L-aspartate = D-aspartate
Other name(s): D-aspartate racemase; McyF
Systematic name: aspartate racemase
Comments: Also acts, at half the rate, on L-alanine.
Links to other databases: BRENDA, EXPASY, KEGG, PDB, CAS registry number: 37237-56-2
References:
1. Lamont, H.C., Staudenbauer, W.L. and Strominger, J.L. Partial purification and characterization of an aspartate racemase from Streptococcus faecalis. J. Biol. Chem. 247 (1972) 5103-5106. [PMID: 4626916]
2. Yamauchi, T., Choi, S.Y., Okada, H., Yohda, M., Kumagai, H., Esaki, N. and Soda, K. Properties of aspartate racemase, a pyridoxal 5'-phosphate-independent amino acid racemase. J. Biol. Chem. 267 (1992) 18361-18364. [PMID: 1526977]
3. Liu, L., Iwata, K., Kita, A., Kawarabayasi, Y., Yohda, M. and Miki, K. Crystal structure of aspartate racemase from Pyrococcus horikoshii OT3 and its implications for molecular mechanism of PLP-independent racemization. J. Mol. Biol. 319 (2002) 479-489. [PMID: 12051922]
4. Sielaff, H., Dittmann, E., Tandeau De Marsac, N., Bouchier, C., von Dühren, H., Börner, T. and Schwecke, T. The mcyF gene of the microcystin biosynthetic gene cluster from Microcystis aeruginosa encodes an aspartate racemase. Biochem. J. 373 (2003) 909-916. [PMID: 12713441]
5. Yamashita, T., Ashiuchi, M., Ohnishi, K., Kato, S., Nagata, S. and Misono, H. Molecular identification of monomeric aspartate racemase from Bifidobacterium bifidum. Eur. J. Biochem. 271 (2004) 4798-4803. [PMID: 15606767]
Accepted name: nocardicin-A epimerase
Reaction: isonocardicin A = nocardicin A
Other name(s): isonocardicin A epimerase
Systematic name: nocardicin-A epimerase
Comments: The (9'S) configuration of isonocardicin A is converted into the (9'R) configuration.
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 118246-75-6
References:
1. Wilson, B.A., Bantia, S., Salituro, G.M., Reeve, A.M. and Townsend, C.A. Cell-free biosynthesis of nocardicin-A from nocardicin-E and S-adenosylmethionine. J. Am. Chem. Soc. 110 (1988) 8238-8239.
Accepted name: 2-aminohexano-6-lactam racemase
Reaction: L-2-aminohexano-6-lactam = D-2-aminohexano-6-lactam
Other name(s): α-amino-ε-caprolactam racemase
Systematic name: 2-aminohexano-6-lactam racemase
Comments: Contains pyridoxal 5'-phosphate. Also racemises 2-aminopentano-5-lactam (α-amino-δ-valerolactam) and 2-amino-4-thiahexano-6-lactam (where S replaces CH2 of C-4). It does not catalyse the racemisation of α-amino acids but has some transaminase activity with them.
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 52652-64-9
References:
1. Ahmed, S.A., Esaki, N., Tanaka, H., Soda, K. L-α-Amino-β-thio-ε-caprolactam, a new sulfur-containing substrate for α-amino-ε-caprolactam racemase. FEBS Lett. 174 (1984) 76-79.
2. Ahmed, S.A., Esaki, N., Tanaka, H., Soda, K. Mechanism of α-amino-ε-caprolactam racemase reaction. Biochemistry 25 (1986) 385-388. [PMID: 3955003]
3. Okazaki, S., Suzuki, A., Mizushima, T., Kawano, T., Komeda, H., Asano, Y. and Yamane, T. The novel structure of a pyridoxal 5'-phosphate-dependent fold-type I racemase, α-amino-ε-caprolactam racemase from Achromobacter obae. Biochemistry 48 (2009) 941–950. [PMID: 19146406]
Accepted name: protein-serine epimerase
Reaction: [protein]-L-serine = [protein]-D-serine
Other name(s): protein-serine racemase
Systematic name: [protein]-serine epimerase
Comments: the enzyme specifically interconverts the configuration of Ser-46 of the peptide ω-agatoxin-KT, found in the venom of the funnel web spider, Agelenopsis aperta, but not that of the other serine residue, Ser-28.
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 169592-52-3
References:
1. Shikata, Y., Watanabe, T., Teramoto, T., Inoue, A., Kawakami, Y., Nishizawa, Y., Katayama, K., Kuwada, M. Isolation and characterization of a peptide isomerase from funnel web spider venom. J. Biol. Chem. 270 (1995) 16719-16723. [PMID: 7622482]
Accepted name: isopenicillin-N epimerase
Reaction: isopenicillin N = penicillin N
For diagram click here.
Systematic name: penicillin-N 5-amino-5-carboxypentanoyl-epimerase
Comments: This enzyme contains pyridoxal phosphate. Epimerization at C-5 of the 5-amino-5-carboxypentanoyl group to form penicillin N is required to make a substrate for EC 1.14.20.1, deactoxycephalosporin-C synthase, to produce cephalosporins. Forms part of the penicillin biosynthesis pathway (for pathway, click here).
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 88201-43-8
References:
1. Usui, S. and Yu, C.-A. Purification and properties of isopenicillin-N epimerase from Streptomyces clavuligerus. Biochim. Biophys. Acta 999 (1989) 78-85. [PMID: 2804141]
2. Laiz, L., Liras, P., Castro, J.M. and Martín, J.F. Purification and characterization of the isopenicillin-N epimerase from Nocardia lactamdurans. J. Gen. Microbiol. 136 (1990) 663-671.
3. Cantwell, C., Beckmann, R., Whiteman, P., Queener, S.W. and Abraham, E.P. Isolation of deacetoxycephalosporin-c from fermentation broths of Penicillium chrysogenum transformants - construction of a new fungal biosynthetic-pathway. Proc. R. Soc. Lond. B Biol. Sci. 248 (1992) 283-289. [PMID: 1354366]
4. Yeh, W.K., Ghag, S.K. and Queener, S.W. Enzymes for epimerization of isopenicillin N, ring expansion of penicillin N, and 3'-hydroxylation of deacetoxycephalosporin C. Function, evolution, refolding, and enzyme engineering. Ann. N.Y. Acad. Sci. 672 (1992) 396-408.
Accepted name: serine racemase
Reaction: L-serine = D-serine
Other name(s): SRR
Systematic name: serine racemase
Comments: A pyridoxal-phosphate protein that is highly selective for L-serine as substrate. D-Serine is found in type-II astrocytes in mammalian brain, where it appears to be an endogenous ligand of the glycine site of N-methyl-D-aspartate (NMDA) receptors [1,2]. The reaction can also occur in the reverse direction but does so more showly at physiological serine concentrations [4].
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number:
References:
1. Wolosker, H., Blackshaw, S. and Snyder, S.H. Serine racemase: a glial enzyme synthesizing D-serine to regulate glutamate-N-methyl-D-aspartate neurotransmission. Proc. Natl. Acad. Sci. USA 96 (1999) 13409-13414. [PMID: 10557334]
2. Wolosker, H., Sheth, K.N., Takahashi, M., Mothet, J.P., Brady, R.O., Jr., Ferris, C.D. and Snyder, S.H. Purification of serine racemase: biosynthesis of the neuromodulator D-serine. Proc. Natl. Acad. Sci. USA 96 (1999) 721-725. [PMID: 9892700]
3. De Miranda, J., Santoro, A., Engelender, S. and Wolosker, H. Human serine racemase: moleular cloning, genomic organization and functional analysis. Gene 256 (2000) 183-188. [PMID: 11054547]
4. Foltyn, V.N., Bendikov, I., De Miranda, J., Panizzutti, R., Dumin, E., Shleper, M., Li, P., Toney, M.D., Kartvelishvily, E. and Wolosker, H. Serine racemase modulates intracellular D-serine levels through an α,β-elimination activity. J. Biol. Chem. 280 (2005) 1754-1763. [PMID: 15536068]
Accepted name: lactate racemase
Reaction: (S)-lactate = (R)-lactate
Other name(s): lacticoracemase; hydroxyacid racemase; lactic acid racemase
Systematic name: lactate racemase
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 9024-05-9
References:
1. Huennekens, F.M., Mahler, H.R. and Nordmann, J. Studies on the cyclophorase system. XVII. The occurrence and properties of an α-hydroxy acid racemase. Arch. Biochem. 30 (1951) 77-89.
2. Kitahara, K., Obayashi, A. and Fukui, S. Racemase I cell-free racemase. Enzymologia 15 (1953) 259-266.
Accepted name: mandelate racemase
Reaction: (S)-mandelate = (R)-mandelate
Systematic name: mandelate racemase
Links to other databases: BRENDA, EXPASY, KEGG, UM-BBD, PDB, CAS registry number: 9024-04-8
References:
1. Gunsalus, C.F., Stanier, R.Y. and Gunsalus, I.C. The enzymatic conversion of mandelic acid to benzoic acid. III. Fractionation and properties of the soluble enzymes. J. Bacteriol. 66 (1953) 548-553.
Accepted name: 3-hydroxybutyryl-CoA epimerase
Reaction: (S)-3-hydroxybutanoyl-CoA = (R)-3-hydroxybutanoyl-CoA
Other name(s): 3-hydroxybutyryl coenzyme A epimerase; 3-hydroxyacyl-CoA epimerase
Systematic name: 3-hydroxybutanoyl-CoA 3-epimerase
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 9024-21-9
References:
1. Stern, J.R., del Campillo, A. and Lehninger, A.L. Enzymatic racemization of β-hydroxybutyryl-S-CoA and the stereospecificity of enzymes of the fatty acid cycle. J. Am. Chem. Soc. 77 (1955) 1073-1074.
2. Wakil, S.J. D(-)β-Hydroxybutyryl CoA dehydrogenase. Biochim. Biophys. Acta 18 (1955) 314-315.
Accepted name: acetoin racemase
Reaction: (S)-acetoin = (R)-acetoin
Other name(s): acetylmethylcarbinol racemase
Systematic name: acetoin racemase
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 37318-32-4
References:
1. Taylor, M.B. and Juni, E. Stereoisomeric specificities of 2,3-butanediol dehydrogenases. Biochim. Biophys. Acta 39 (1960) 448-457.
Accepted name: tartrate epimerase
Reaction: (R,R)-tartrate = meso-tartrate
Other name(s): tartaric racemase
Systematic name: tartrate epimerase
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 37318-33-5
References:
1. Ranjan, S., Patnaik, K.K. and Laloraya, M.M. Enzymic conversion of meso-tartrate to dextro-tartrate in tamarind. Naturwissenschaften 48 (1961) 406 only.
Accepted name: isocitrate epimerase
Reaction: (1R,2S)-1-hydroxypropane-1,2,3-tricarboxylate = (1S,2S)-1-hydroxypropane-1,2,3-tricarboxylate
For diagram click here.
Glossary: isocitrate = (1R,2S)-1-hydroxypropane-1,2,3-tricarboxylate = threo-Ds-isocitrate
allocitrate = (1S,2S)-1-hydroxypropane-1,2,3-tricarboxylate = D-erythro-isocitrate
Systematic name: (1R,2S)-1-hydroxypropane-1,2,3-tricarboxylate 1-epimerase
Comments: (1R,2S)-1-hydroxypropane-1,2,3-tricarboxylate is the commonly occurring isomer of isocitrate.
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 81210-68-6
References:
1. Hoshiko, S., Kunimoto, Y., Arima, K. and Beppu, T. Mechanism of L-alloisocitric acid fermentation: isocitrate epimerase activity in the cell-free-extract of Penicillium purpurogenum. Agric. Biol. Chem. 46 (1982) 143-151.