Continued from EC 5.2
EC 5.3.1 Interconverting Aldoses and Ketoses
EC 5.3.2 Interconverting Keto- and Enol-Groups
EC 5.3.3 Transposing C=C Bonds
EC 5.3.4 Transposing S-S Bonds
EC 5.3.99 Other Intramolecular Oxidoreductases
Accepted name: triose-phosphate isomerase
Reaction: D-glyceraldehyde 3-phosphate = glycerone phosphate
For diagram of reaction click here, alternatives click here or click here.
Other name(s): phosphotriose isomerase; triose phosphoisomerase; triose phosphate mutase; D-glyceraldehyde-3-phosphate ketol-isomerase
Systematic name: D-glyceraldehyde-3-phosphate aldose-ketose-isomerase
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9023-78-3
References:
1. Meyer-Arendt, E., Beisenherz, G. and Bücher, T. Triosephosphate isomerase. Naturwissenschaften 40 (1953) 59 only.
2. Meyerhof, O. and Beck, L.V. Triosephosphate isomerase. J. Biol. Chem. 156 (1944) 109-120.
[EC 5.3.1.2 Deleted entry: erythrose isomerase (EC 5.3.1.2 created 1961, deleted 1976)]
Accepted name: D-arabinose isomerase
Reaction: D-arabinose = D-ribulose
For diagram of reaction click here.
Other name(s): D-arabinose(L-fucose) isomerase; L-fucose isomerase; D-arabinose ketol-isomerase; arabinose isomerase (misleading)
Systematic name: D-arabinose aldose-ketose-isomerase
Comments: Requires a divalent metal ion (the enzyme from the bacterium Escherichia coli prefers Mn2+). The enzyme binds the closed form of the sugar and catalyses ring opening to generate a form of open-chain conformation that facilitates the isomerization reaction, which proceeds via an ene-diol mechanism [3]. The enzyme catalyses the aldose-ketose isomerization of several sugars. Most enzymes also catalyse the reaction of EC 5.3.1.25, L-fucose isomerase [3]. The enzyme from the bacterium Falsibacillus pallidus also converts D-altrose to D-psicose [4]. cf. EC 5.3.1.4, L-arabinose isomerase.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9023-81-8
References:
1. Cohen, S.S. Studies on D-ribulose and its enzymatic conversion to D-arabinose. J. Biol. Chem. 201 (1953) 71-84. [PMID: 13044776]
2. Green, M. and Cohen, S.S. Enzymatic conversion of L-fucose to L-fuculose. J. Biol. Chem. 219 (1956) 557-568. [PMID: 13319278]
3. Seemann, J.E. and Schulz, G.E. Structure and mechanism of L-fucose isomerase from Escherichia coli. J. Mol. Biol. 273 (1997) 256-268. [PMID: 9367760]
4. Takeda, K., Yoshida, H., Izumori, K. and Kamitori, S. X-ray structures of Bacillus pallidus D-arabinose isomerase and its complex with L-fucitol. Biochim. Biophys. Acta 1804 (2010) 1359-1368. [PMID: 20123133]
Accepted name: L-arabinose isomerase
Reaction: β-L-arabinopyranose = L-ribulose
For diagram of reaction click here
Other name(s): L-arabinose ketol-isomerase; araA (gene name)
Systematic name: β-L-arabinopyranose aldose-ketose-isomerase
Comments: Requires a divalent metal ion (the enzyme from the bacterium Escherichia coli prefers Mn2+) [2]. The enzyme binds β-L-arabinopyranose [4] and catalyses ring opening to generate a form of open-chain conformation that facilitates the isomerization reaction, which proceeds via an ene-diol mechanism [6]. The enzyme can also convert α-D-galactose to D-tagatose with lower efficiency [5].
Links to other databases: BRENDA, EXPASY, GTD, KEGG, MetaCyc, PDB, CAS registry number: 9023-80-7
References:
1. Heath, E.C., Horecker, B.L., Smyrniotis, P.Z. and Takagi, Y. Pentose formation by Lactobacillus plantarum. II. L-Arabinose isomerase. J. Biol. Chem. 231 (1958) 1031-1037. [PMID: 13539034]
2. Patrick, J.W. and Lee, N. Purification and properties of an L-arabinose isomerase from Escherichia coli. J. Biol. Chem. 243 (1968) 4312-4318. [PMID: 4878429]
3. Nakamatu, T. and Yamanaka, K. Crystallization and properties of L-arabinose isomerase from Lactobacillus gayonii. Biochim. Biophys. Acta 178 (1969) 156-165. [PMID: 5773448]
4. Schray, K.J. and Rose, I.A. Anomeric specificity and mechanism of two pentose isomerases. Biochemistry 10 (1971) 1058-1062. [PMID: 5550812]
5. Cheetham, P.S.J. and Wootton, A.N. Bioconversion of D-galactose into D-tagatose. Enzyme and Microbial Technology 15 (1993) 105-108.
6. Banerjee, S., Anderson, F. and Farber, G.K. The evolution of sugar isomerases. Protein Eng. 8 (1995) 1189-1195. [PMID: 8869631]
7. Manjasetty, B.A. and Chance, M.R. Crystal structure of Escherichia coli L-arabinose isomerase (ECAI), the putative target of biological tagatose production. J. Mol. Biol. 360 (2006) 297-309. [PMID: 16756997]
Accepted name: xylose isomerase
Reaction: α-D-xylopyranose = α-D-xylufuranose
Other name(s): D-xylose isomerase; D-xylose ketoisomerase; D-xylose ketol-isomerase; D-xylose aldose-ketose-isomerase
Systematic name: α-D-xylopyranose aldose-ketose-isomerase
Comments: Contains two divalent metal ions, preferably magnesium, located at different metal-binding sites within the active site. The enzyme catalyses the interconversion of aldose and ketose sugars with broad substrate specificity. The enzyme binds the closed form of its sugar substrate (in the case of xylose and glucose, only the α anomer [4]) and catalyses ring opening to generate a form of open-chain conformation that is coordinated to one of the metal sites. Isomerization proceeds via a hydride-shift mechanism.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, MetaCyc, PDB, CAS registry number: 9023-82-9
References:
1. Hochster, R.M. and Watson, R.W. Enzymatic isomerization of D-xylose to D-xylulose. Arch. Biochem. Biophys. 48 (1954) 120-129. [PMID: 13125579]
2. Slein, M.W. Xylose isomerase from Pasteurella pestis, strain A-1122. J. Am. Chem. Soc. 77 (1955) 1663-1667.
3. Yamanaka, K. Purification, crystallization and properties of the D-xylose isomerase from Lactobacillus brevis. Biochim. Biophys. Acta 151 (1968) 670-680. [PMID: 5646045]
4. Schray, K.J. and Rose, I.A. Anomeric specificity and mechanism of two pentose isomerases. Biochemistry 10 (1971) 1058-1062. [PMID: 5550812]
5. Carrell, H.L., Glusker, J.P., Burger, V., Manfre, F., Tritsch, D. and Biellmann, J.F. X-ray analysis of D-xylose isomerase at 1.9 Å: native enzyme in complex with substrate and with a mechanism-designed inactivator. Proc. Natl. Acad. Sci. USA 86 (1989) 4440-4444. [PMID: 2734296]
6. Collyer, C.A. and Blow, D.M. Observations of reaction intermediates and the mechanism of aldose-ketose interconversion by D-xylose isomerase. Proc. Natl. Acad. Sci. USA 87 (1990) 1362-1366. [PMID: 2304904]
7. Whitlow, M., Howard, A.J., Finzel, B.C., Poulos, T.L., Winborne, E. and Gilliland, G.L. A metal-mediated hydride shift mechanism for xylose isomerase based on the 1.6 Å Streptomyces rubiginosus structures with xylitol and D-xylose. Proteins 9 (1991) 153-173. [PMID: 2006134]
8. Allen, K.N., Lavie, A., Glasfeld, A., Tanada, T.N., Gerrity, D.P., Carlson, S.C., Farber, G.K., Petsko, G.A. and Ringe, D. Role of the divalent metal ion in sugar binding, ring opening, and isomerization by D-xylose isomerase: replacement of a catalytic metal by an amino acid. Biochemistry 33 (1994) 1488-1494. [PMID: 7906142]
Accepted name: ribose-5-phosphate isomerase
Reaction: D-ribose 5-phosphate = D-ribulose 5-phosphate
For diagram of reaction click here, alternative click here.
Other name(s): phosphopentosisomerase; phosphoriboisomerase; ribose phosphate isomerase; 5-phosphoribose isomerase; D-ribose 5-phosphate isomerase; D-ribose-5-phosphate ketol-isomerase
Systematic name: D-ribose-5-phosphate aldose-ketose-isomerase
Comments: Also acts on D-ribose 5-diphosphate and D-ribose 5-triphosphate.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9023-83-0
References:
1. Dickens, F. and Williamson, D.H. Pentose phosphate isomerase and epimerase from animal tissues. Biochem. J. 64 (1956) 567-578.
2. Horecker, B.L., Smyrniotis, P.Z. and Seegmiller, J.E. The enzymatic conversion of 6-phosphogluconate to ribulose-5-phosphate and ribose-5-phosphate. J. Biol. Chem. 193 (1951) 383-396.
3. Hurwitz, J., Weissbach, A., Horecker, B.L. and Smyrniotis, P.Z. Spinach phosphoribulokinase. J. Biol. Chem. 218 (1956) 769-783.
Accepted name: mannose isomerase
Reaction: D-mannose = D-fructose
Other name(s): D-mannose isomerase; D-mannose ketol-isomerase
Systematic name: D-mannose aldose-ketose-isomerase
Comments: Also acts on D-lyxose and D-rhamnose.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9031-25-8
References:
1. Palleroni, N.J. and Doudoroff, M. Mannose isomerase of Pseudomonas saccharophila. J. Biol. Chem. 218 (1956) 535-548.
Accepted name: mannose-6-phosphate isomerase
Reaction: D-mannose 6-phosphate = D-fructose 6-phosphate
For diagram click here.
Other name(s): phosphomannose isomerase; phosphohexomutase; phosphohexoisomerase; mannose phosphate isomerase; phosphomannoisomerase; D-mannose-6-phosphate ketol-isomerase
Systematic name: D-mannose-6-phosphate aldose-ketose-isomerase
Comments: A zinc protein.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9023-88-5
References:
1. Bruns, F.H., Noltmann, E. and Willemsen, A. Phosphomannose-isomerase. I. Über die Aktivitätsmessung und die Sulfhydryl-sowie die metallabhängigkeit der Enzymirkung in einigen Tierischen Geweben. Biochem. Z. 330 (1958) 411-420.
2. Gracy, R.W. and Noltmann, E.A. Studies on phosphomannose isomerase. II. Characterization as a zinc metalloenzyme. J. Biol. Chem. 243 (1968) 4109-4116. [PMID: 4969968]
3. Slein, M.W. Phosphomannose isomerase. J. Biol. Chem. 186 (1950) 753-761.
Accepted name: glucose-6-phosphate isomerase
Reaction: α-D-glucose 6-phosphate = β-D-fructofuranose 6-phosphate
For diagram of reaction click here, another example click here, another example click here another example click here
Other name(s): phosphohexose isomerase; phosphohexomutase; oxoisomerase; hexosephosphate isomerase; phosphosaccharomutase; phosphoglucoisomerase; phosphohexoisomerase; phosphoglucose isomerase; glucose phosphate isomerase; hexose phosphate isomerase; D-glucose-6-phosphate ketol-isomerase
Systematic name: α-D-glucose-6-phosphate aldose-ketose-isomerase (configuration-inverting)
Comments: The enzyme from yeast catalyses the reversible conversion specifically between the α-D-glucose 6-phosphate and β-D-fructofuranose 6-phosphate. The enzyme also catalyses the anomerization of both D-hexose 6-phosphates [7].
Links to other databases: BRENDA, EXPASY, GTD, KEGG, MetaCyc, PDB, CAS registry number: 9001-41-6
References:
1. Ramasarma, T. and Giri, K.V. Phosphoglucose isomerase of green gram (Phaseolus radiatus). Arch. Biochem. Biophys. 62 (1956) 91-96. [PMID: 13314642]
2. Tsuboi, K.K., Estrada, J. and Hudson, P.B. Enzymes of the human erythrocytes. IV. Phosphoglucose isomerase, purification and properties. J. Biol. Chem. 231 (1958) 19-29. [PMID: 13538944]
3. Noltmann, E. and Bruns, F.H. Reindarstellung und Eigenschaften von Phosphoglucose-isomerase aus Hefe. Biochem. Z. 331 (1959) 436-445.
4. Baich, A., Wolfe, R.G. and Reithel, F.J. The enzymes of mammary gland. I. Isolation of phosphoglucose isomerase. J. Biol. Chem. 235 (1960) 3130-3133. [PMID: 13685918]
5. Noltmann, E.A. Isolation of crystalline phosphoglucose isomerase from rabbit muscle. J. Biol. Chem. 239 (1964) 1545-1550. [PMID: 14189891]
6. Nakagawa, Y. and Noltmann, E.A. Isolation of crystalline phosphoglucose isomerase from brewers' yeast. J. Biol. Chem. 240 (1965) 1877-1881. [PMID: 14299604]
7. Willem, R., Biesemans, M., Hallenga, K., Lippens, G., Malaisse-Lagae, F. and Malaisse, W.J. Dual anomeric specificity and dual anomerase activity of phosphoglucoisomerase quantified by two-dimensional phase-sensitive 13C EXSY NMR. J. Biol. Chem. 267 (1992) 210-217. [PMID: 1730590]
[EC 5.3.1.10 transferred entry: now EC 3.5.99.6 glucosamine-6-phosphate deaminase (EC 5.3.1.10 created 1961, deleted 2000)]
[EC 5.3.1.11 Deleted entry: acetylglucosaminephosphate isomerase (EC 5.3.1.11 created 1961, deleted 1978)]
Accepted name: glucuronate isomerase
Reaction: D-glucuronate = D-fructuronate
Other name(s): uronic isomerase; uronate isomerase; D-glucuronate isomerase; uronic acid isomerase; D-glucuronate ketol-isomerase
Systematic name: D-glucuronate aldose-ketose-isomerase
Comments: Also converts D-galacturonate to D-tagaturonate.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9023-87-4
References:
1. Ashwell, G., Wahba, A.J. and Hickman, J. Uronic acid metabolism in bacteria. I. Purification and properties of uronic acid isomerase in Escherichia coli. J. Biol. Chem. 235 (1960) 1559-1565.
2. Kilgore, W.W. and Starr, M.P. Catabolism of galacturonic and glucuronic acids by Erwinia carotovora. J. Biol. Chem. 234 (1959) 2227-2235.
Accepted name: arabinose-5-phosphate isomerase
Reaction: D-arabinose 5-phosphate = D-ribulose 5-phosphate
For diagram of reaction click here.
Other name(s): kdsD (gene name); gutQ (gene name); arabinose phosphate isomerase; phosphoarabinoisomerase; D-arabinose-5-phosphate ketol-isomerase
Systematic name: D-arabinose-5-phosphate aldose-ketose-isomerase
Comments: The enzyme is involved in the pathway for synthesis of 3-deoxy-D-manno-octulosonate (Kdo), a component of bacterial lipopolysaccharides and plant call walls.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9023-86-3
References:
1. Volk, W.A. Purification and properties of phosphoarabinoisomerase from Propionibacterium pentosaceum. J. Biol. Chem. 235 (1960) 1550-1553.
2. Lim, R. and Cohen, S.S. D-Phosphoarabinoisomerase and D-ribulokinase in Escherichia coli. J. Biol. Chem. 241 (1966) 4304-4315. [PMID: 5332197]
3. Meredith, T.C. and Woodard, R.W. Identification of GutQ from Escherichia coli as a D-arabinose 5-phosphate isomerase. J. Bacteriol. 187 (2005) 6936-6942. [PMID: 16199563]
4. Gourlay, L.J., Sommaruga, S., Nardini, M., Sperandeo, P., Deho, G., Polissi, A. and Bolognesi, M. Probing the active site of the sugar isomerase domain from E. coli arabinose-5-phosphate isomerase via X-ray crystallography. Protein Sci. 19 (2010) 2430-2439. [PMID: 20954237]
5. Chiu, H.J., Grant, J.C., Farr, C.L., Jaroszewski, L., Knuth, M.W., Miller, M.D., Elsliger, M.A., Deacon, A.M., Godzik, A., Lesley, S.A. and Wilson, I.A. Structural analysis of arabinose-5-phosphate isomerase from Bacteroides fragilis and functional implications. Acta Crystallogr. D Biol. Crystallogr. 70 (2014) 2640-2651. [PMID: 25286848]
Accepted name: L-rhamnose isomerase
Reaction: L-rhamnose = L-rhamnulose
For diagram of reaction click here.
Other name(s): rhamnose isomerase; L-rhamnose ketol-isomerase
Systematic name: L-rhamnose aldose-ketose-isomerase
Comments: Contains two divalent metal ions located at different metal-binding sites within the active site. The enzyme binds the closed ring form of the substrate and catalyses ring opening to generate a form of open-chain conformation that is coordinated to one of the metal sites. Isomerization proceeds via a hydride-shift mechanism. While the enzyme from the bacterium Escherichia coli is specific for L-rhamnose, the enzyme from the bacterium Pseudomonas stutzeri has broad substrate specificity and catalyses the interconversion of L-mannose and L-fructose, L-lyxose and L-xylulose, D-ribose and D-ribulose, and D-allose and D-psicose [2].
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9023-84-1
References:
1. Domagk, G.F. and Zech, R. Über den Abbau der Desoxyzucker durch Bakterienenzyme. I. L-Rhamnose-Isomerase aus Lactobacillus plantarum. Biochem. Z. 339 (1963) 145-153.
2. Leang, K., Takada, G., Ishimura, A., Okita, M. and Izumori, K. Cloning, nucleotide sequence, and overexpression of the L-rhamnose isomerase gene from Pseudomonas stutzeri in Escherichia coli. Appl. Environ. Microbiol. 70 (2004) 3298-3304. [PMID: 15184124]
3. Korndorfer, I.P., Fessner, W.D. and Matthews, B.W. The structure of rhamnose isomerase from Escherichia coli and its relation with xylose isomerase illustrates a change between inter and intra-subunit complementation during evolution. J. Mol. Biol. 300 (2000) 917-933. [PMID: 10891278]
4. Yoshida, H., Yamada, M., Ohyama, Y., Takada, G., Izumori, K. and Kamitori, S. The structures of L-rhamnose isomerase from Pseudomonas stutzeri in complexes with L-rhamnose and D-allose provide insights into broad substrate specificity. J. Mol. Biol. 365 (2007) 1505-1516. [PMID: 17141803]
Accepted name: D-lyxose ketol-isomerase
Reaction: D-lyxose = D-xylulose
Other name(s): D-lyxose isomerase; D-lyxose ketol-isomerase
Systematic name: D-lyxose aldose-ketose-isomerase
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 37318-42-6
References:
1. Anderson, R.L. and Allison, D.P. Purification and characterization of D-lyxose isomerase. J. Biol. Chem. 240 (1965) 2367-2372.
Accepted name: 1-(5-phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino]imidazole-4-carboxamide isomerase
Reaction: 1-(5-phospho-β-D-ribosyl)-5-[(5-phospho-β-D-ribosylamino)methylideneamino]imidazole-4-carboxamide = 5-[(5-phospho-1-deoxy-β-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-β-D-ribosyl)imidazole-4-carboxamide
For diagram click here.
Other name(s): N-(5'-phospho-D-ribosylformimino)-5-amino-1-(5"-phosphoribosyl)-4-imidazolecarboxamide isomerase; phosphoribosylformiminoaminophosphoribosylimidazolecarboxamide isomerase; N-(phosphoribosylformimino) aminophosphoribosylimidazolecarboxamide isomerase; 1-(5-phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino)imidazole-4-carboxamide ketol-isomerase; 1-(5-phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino]imidazole-4-carboxamide aldose-ketose-isomerase
Systematic name: 1-(5-phospho-β-D-ribosyl)-5-[(5-phospho-β-D-ribosylamino)methylideneamino]imidazole-4-carboxamide aldose-ketose-isomerase
Comments: Involved in histidine biosynthesis
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37318-43-7
References:
1. Margolies, M.N. and Goldberger, R.F. Isolation of the fourth (isomerase) of histidine biosynthesis from Salmonella typhimurium. J. Biol. Chem. 241 (1966) 3262-3269. [PMID: 5330429]
Accepted name: 5-dehydro-4-deoxy-D-glucuronate isomerase
Reaction: 5-dehydro-4-deoxy-D-glucuronate = 3-deoxy-D-glycero-2,5-hexodiulosonate
Glossary: 5-dehydro-4-deoxy-D-glucuronate = (4S,5R)-4,5-dihydroxy-2,6-dioxohexanoate
3-deoxy-D-glycero-2,5-hexodiulosonate = (4S)-4,6-dihydroxy-2,5-dioxohexanoate
Other name(s): 4-deoxy-L-threo-5-hexulose uronate isomerase; 4-deoxy-L-threo-5-hexosulose-uronate ketol-isomerase; kduI (gene name)
Systematic name: 5-dehydro-4-deoxy-D-glucuronate aldose-ketose-isomerase
Comments: The enzyme is involved in the degradation of polygalacturonate, a later stage in the degradation of pectin by many microorganisms.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37318-44-8
References:
1. Preiss, J. 4-Deoxy-L-threo-5-hexosulose uronic acid isomerase. Methods Enzymol. 9 (1966) 602-604.
2. Condemine, G. and Robert-Baudouy, J. Analysis of an Erwinia chrysanthemi gene cluster involved in pectin degradation. Mol. Microbiol. 5 (1991) 2191-2202. [PMID: 1766386]
3. Dunten, P., Jaffe, H. and Aksamit, R.R. Crystallization of 5-keto-4-deoxyuronate isomerase from Escherichia coli. Acta Crystallogr. D Biol. Crystallogr. 54 (1998) 678-680. [PMID: 9761873]
4. Crowther, R.L. and Georgiadis, M.M. The crystal structure of 5-keto-4-deoxyuronate isomerase from Escherichia coli. Proteins 61 (2005) 680-684. [PMID: 16152643]
[EC 5.3.1.18 Deleted entry: glucose isomerase. Reaction is due to EC 5.3.1.9 glucose-6-phosphate isomerase, in the presence of arsenate, or EC 5.3.1.5 xylose isomerase (EC 5.3.1.18 created 1972, deleted 1978)]
[EC 5.3.1.19 Transferred entry: now EC 2.6.1.16 glutamine-fructose-6-phosphate aminotransferase (isomerizing) (EC 5.3.1.19 created 1972, deleted 1984)]
Accepted name: ribose isomerase
Reaction: D-ribose = D-ribulose
Other name(s): D-ribose isomerase; D-ribose ketol-isomerase
Systematic name: D-ribose aldose-ketose-isomerase
Comments: Also acts on L-lyxose and L-rhamnose.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, CAS registry number: 57534-76-6
References:
1. Izumori, K., Rees, A.W. and Elbein, A.D. Purification, crystallization, and properties of D-ribose isomerase from Mycobacterium smegmatis. J. Biol. Chem. 250 (1975) 8085-8087. [PMID: 240851]
Accepted name: corticosteroid side-chain-isomerase
Reaction: 11-deoxycorticosterone = 20-hydroxy-3-oxopregn-4-en-21-al
Other Name(s): 11-deoxycorticosterone ketol-isomerase
Systematic name: 11-deoxycorticosterone aldose-ketose-isomerase
Comments: An epimerization at C-20 and C-21 is probably catalysed by the same enzyme.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 75139-73-0
References:
1. Martin, K.O., Oh, S.-W., Lee, H.J. and Monder, C. Studies on 21-3H-labeled corticosteroids: evidence for isomerization of the ketol side chain of 11-deoxycorticosterone by a hamster liver enzyme. Biochemistry 16 (1977) 3803-3809. [PMID: 901753]
2. Monder, C., Martin, K.O. and Bogumil, J. Presence of epimerase activity in hamster liver corticosteroid side chain isomerase. J. Biol. Chem. 255 (1980) 7192-7198. [PMID: 7391077]
Accepted name: hydroxypyruvate isomerase
Reaction: hydroxypyruvate = 2-hydroxy-3-oxopropanoate
Glossary: 2-hydroxy-3-oxopropanoate = tartronate semialdehyde
Other Name(s): hydroxypyruvate ketol-isomerase
Systematic name: hydroxypyruvate aldose-ketose-isomerase
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 74812-48-9
References:
1. De Windt, F.E. and van der Drift, D. Purification and some properties of hydroxypyruvate isomerase of Bacillus fastidiosus. Biochim. Biophys. Acta 613 (1980) 556-562. [PMID: 7448201]
Accepted name: S-methyl-5-thioribose-1-phosphate isomerase
Reaction: S-methyl-5-thio-α-D-ribose 1-phosphate = S-methyl-5-thio-D-ribulose 1-phosphate
For diagram click here.
Other name(s): methylthioribose 1-phosphate isomerase; 1-PMTR isomerase; 5-methylthio-5-deoxy-D-ribose-1-phosphate ketol-isomerase; S-methyl-5-thio-5-deoxy-D-ribose-1-phosphate ketol-isomerase; S-methyl-5-thio-5-deoxy-D-ribose-1-phosphate aldose-ketose-isomerase; 1-phospho-5′-S-methylthioribose isomerase; S-methyl-5-thio-D-ribose-1-phosphate aldose-ketose-isomerase
Systematic name: S-methyl-5-thio-α-D-ribose-1-phosphate aldose-ketose-isomerase
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 91608-95-6
References:
1. Ghoda, L.Y., Savarese, T.M., Dexter, D.L., Parks, R.E., Jr., Trackman, P.C. and Abeles, R.H. Characterization of a defect in the pathway for converting 5'-deoxy-5'-methylthioadenosine to methionine in a subline of a cultured heterogeneous human colon carcinoma. J. Biol. Chem. 259 (1984) 6715-6719. [PMID: 6725268]
2. Trackman, P.C. and Abeles, R.H. Methionine synthesis from 5'-S-methylthioadenosine - resolution of enzyme-activities and identification of 1-phospho-5-S-methylthioribulose. J. Biol. Chem. 258 (1983) 6717-6720. [PMID: 6853500]
3. Furfine, E.S. and Abeles, R.H. Intermediates in the conversion of 5'-S-methylthioadenosine to methionine in Klebsiella pneumoniae. J. Biol. Chem. 263 (1988) 9598-9606. [PMID: 2838472]
Accepted name: phosphoribosylanthranilate isomerase
Reaction: N-(5-phospho-β-D-ribosyl)anthranilate = 1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate
For diagram click here.
Other name(s): PRA isomerase; PRAI; IGPS:PRAI (indole-3-glycerol-phosphate synthetase/N-5'-phosphoribosylanthranilate isomerase complex); N-(5-phospho-β-D-ribosyl)anthranilate ketol-isomerase
Systematic name: N-(5-phospho-β-D-ribosyl)anthranilate aldose-ketose-isomerase
Comments: In some organisms, this enzyme is part of a multifunctional protein, together with one or more other components of the system for the biosynthesis of tryptophan [EC 2.4.2.18 (anthranilate phosphoribosyltransferase), EC 4.1.1.48 (indole-3-glycerol-phosphate synthase), EC 4.1.3.27 (anthranilate synthase) and EC 4.2.1.20 (tryptophan synthase)].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37259-82-8
References:
1. Braus, G.H., Luger, K., Paravicini, G., Schmidheini, T., Kirschner, K. and Hütter, R. The role of the TRP1 gene in yeast tryptophan biosynthesis. J. Biol. Chem. 263 (1988) 7868-7875. [PMID: 3286643]
2. Creighton, T.E. and Yanofsky, C. Chorismate to tryptophan (Escherichia coli) - anthranilate synthetase, PR transferase, PRA isomerase, InGP synthetase, tryptophan synthetase. Methods Enzymol. 17A (1970) 365-380.
3. Hütter, R., Niederberger, P. and DeMoss, J.A. Tryptophan biosynthetic genes in eukaryotic microorganisms. Annu. Rev. Microbiol. 40 (1986) 55-77.
Accepted name: L-fucose isomerase
Reaction: L-fucose = L-fuculose
Other Name(s): L-fucose ketol-isomerase
Systematic name: L-fucose aldose-ketose-isomerase
Comments: Requires a divalent metal ion (the enzyme from the bacterium Escherichia coli prefers Mn2+). The enzyme binds the closed form of the sugar and catalyses ring opening to generate a form of open-chain conformation that facilitates the isomerization reaction, which proceeds via an ene-diol mechanism [3]. The enzyme from Escherichia coli can also convert D-arabinose to D-ribulose [1]. The enzyme from the thermophilic bacterium Caldicellulosiruptor saccharolyticus also converts D-altrose to D-psicose and L-galactose to L-tagatose [4].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 60063-83-4
References:
1. Green, M. and Cohen, S.S. Enzymatic conversion of L-fucose to L-fuculose. J. Biol. Chem. 219 (1956) 557-568. [PMID: 13319278]
2. Lu, Z., Lin, E.C.C. The nucleotide sequence of Escherichia coli genes for L-fucose dissimilation. Nucleic Acids Res. 17 (1989) 4883-4884. [PMID: 2664711]
3. Seemann, J.E. and Schulz, G.E. Structure and mechanism of L-fucose isomerase from Escherichia coli. J. Mol. Biol. 273 (1997) 256-268. [PMID: 9367760]
4. Ju, Y.H. and Oh, D.K. Characterization of a recombinant L-fucose isomerase from Caldicellulosiruptor saccharolyticus that isomerizes L-fucose, D-arabinose, D-altrose, and L-galactose. Biotechnol. Lett. 32 (2010) 299-304. [PMID: 19856146]
Accepted name: galactose-6-phosphate isomerase
Reaction: D-galactose 6-phosphate = D-tagatose 6-phosphate
Other Name(s): D-galactose-6-phosphate ketol-isomerase
Systematic name: D-galactose-6-phosphate aldose-ketose-isomerase
Comments: involved in the tagatose 6-phosphate pathway of lactose catabolism in bacteria.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 39433-98-2
References:
1. De Vos, W.M., Boerrigter, I., Van Rooijen, R.J., Reiche, B., Hengstenberg, W. Characterization of the lactose-specific enzymes of the phosphotransferase system in Lactococcus lactis. J. Biol. Chem. 265 (1990) 22554-22560. [PMID: 2125052]
2. Van Rooijen, R.J., Van Schalkwijk, S., De Vos, W.M. Molecular cloning, characterization, and nucleotide sequence of the tagatose 6-phosphate pathway gene cluster of the lactose operon of Lactococcus lactis. J. Biol. Chem. 266 (1991) 7176-7181. [PMID: 1901863]
Accepted name: 6-phospho-3-hexuloisomerase
Reaction: D-arabino-hex-3-ulose 6-phosphate = D-fructose 6-phosphate
For diagram of reaction, click here
Other name(s): 3-hexulose-6-phosphate isomerase; phospho-3-hexuloisomerase; PHI; 6-phospho-3-hexulose isomerase; YckF
Systematic name: D-arabino-3-hexulose-6-phosphate isomerase
Comments: This enzyme, along with EC 4.1.2.43, 3-hexulose-6-phosphate synthase, plays a key role in the ribulose-monophosphate cycle of formaldehyde fixation, which is present in many microorganisms that are capable of utilizing C1-compounds [1]. The hyperthermophilic and anaerobic archaeon Pyrococcus horikoshii OT3 constitutively produces a bifunctional enzyme that sequentially catalyses the reactions of EC 4.1.2.43 (3-hexulose-6-phosphate synthase) and this enzyme [4].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Ferenci, T., Strøm, T. and Quayle, J.R. Purification and properties of 3-hexulose phosphate synthase and phospho-3-hexuloisomerase from Methylococcus capsulatus. Biochem. J. 144 (1974) 477-486. [PMID: 4219834]
2. Yurimoto, H., Kato, N. and Sakai, Y. Assimilation, dissimilation, and detoxification of formaldehyde, a central metabolic intermediate of methylotrophic metabolism. Chem. Rec. 5 (2005) 367-375. [PMID: 16278835]
3. Kato, N., Yurimoto, H. and Thauer, R.K. The physiological role of the ribulose monophosphate pathway in bacteria and archaea. Biosci. Biotechnol. Biochem. 70 (2006) 10-21. [PMID: 16428816]
4. Orita, I., Yurimoto, H., Hirai, R., Kawarabayasi, Y., Sakai, Y. and Kato, N. The archaeon Pyrococcus horikoshii possesses a bifunctional enzyme for formaldehyde fixation via the ribulose monophosphate pathway. J. Bacteriol. 187 (2005) 3636-3642. [PMID: 15901685]
5. Martinez-Cruz, L.A., Dreyer, M.K., Boisvert, D.C., Yokota, H., Martinez-Chantar, M.L., Kim, R. and Kim, S.H. Crystal structure of MJ1247 protein from M. jannaschii at 2.0 Å resolution infers a molecular function of 3-hexulose-6-phosphate isomerase. Structure 10 (2002) 195-204. [PMID: 11839305]
6. Taylor, E.J., Charnock, S.J., Colby, J., Davies, G.J. and Black, G.W. Cloning, purification and characterization of the 6-phospho-3-hexulose isomerase YckF from Bacillus subtilis. Acta Crystallogr. D Biol. Crystallogr. 57 (2001) 1138-1140. [PMID: 11468398]
Accepted name: D-sedoheptulose-7-phosphate isomerase
Reaction: D-sedoheptulose 7-phosphate = D-glycero-D-manno-heptose 7-phosphate
Other name(s): sedoheptulose-7-phosphate isomerase; phosphoheptose isomerase; gmhA (gene name); lpcA (gene name)
Systematic name: D-glycero-D-manno-heptose 7-phosphate aldose-ketose-isomerase
Comments: In Gram-negative bacteria the enzyme is involved in biosynthesis of ADP-L-glycero-β-D-manno-heptose, which is utilized for assembly of the lipopolysaccharide inner core. In Gram-positive bacteria the enzyme is involved in biosynthesis of GDP-D-glycero-α-D-manno-heptose, which is required for assembly of S-layer glycoprotein.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Kneidinger, B., Marolda, C., Graninger, M., Zamyatina, A., McArthur, F., Kosma, P., Valvano, M.A. and Messner, P. Biosynthesis pathway of ADP-L-glycero-β-D-manno-heptose in Escherichia coli. J. Bacteriol. 184 (2002) 363-369. [PMID: 11751812]
2. Kneidinger, B., Graninger, M., Puchberger, M., Kosma, P. and Messner, P. Biosynthesis of nucleotide-activated D-glycero-D-manno-heptose. J. Biol. Chem. 276 (2001) 20935-20944. [PMID: 11279237]
3. Valvano, M.A., Messner, P. and Kosma, P. Novel pathways for biosynthesis of nucleotide-activated glycero-manno-heptose precursors of bacterial glycoproteins and cell surface polysaccharides. Microbiology 148 (2002) 1979-1989. [PMID: 12101286]
4. Kim, M.S. and Shin, D.H. A preliminary X-ray study of sedoheptulose-7-phosphate isomerase from Burkholderia pseudomallei. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 65 (2009) 1110-1112. [PMID: 19923728]
5. Taylor, P.L., Blakely, K.M., de Leon, G.P., Walker, J.R., McArthur, F., Evdokimova, E., Zhang, K., Valvano, M.A., Wright, G.D. and Junop, M.S. Structure and function of sedoheptulose-7-phosphate isomerase, a critical enzyme for lipopolysaccharide biosynthesis and a target for antibiotic adjuvants. J. Biol. Chem. 283 (2008) 2835-2845. [PMID: 18056714]
Accepted name: ribose-1,5-bisphosphate isomerase
Reaction: α-D-ribose 1,5-bisphosphate = D-ribulose 1,5-bisphosphate
For diagram of reaction click here.
Other name(s): R15P isomerase; ribulose 1,5-bisphosphate synthase; RuBP synthase
Systematic name: α-D-ribose 1,5-bisphosphate aldose-ketose-isomerase
Comments: This archaeal enzyme is involved in AMP metabolism and CO2 fixation through type III RubisCO enzymes. The enzyme is activated by cAMP [2].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Sato, T., Atomi, H. and Imanaka, T. Archaeal type III RuBisCOs function in a pathway for AMP metabolism. Science 315 (2007) 1003-1006. [PMID: 17303759]
2. Aono, R., Sato, T., Yano, A., Yoshida, S., Nishitani, Y., Miki, K., Imanaka, T. and Atomi, H. Enzymatic characterization of AMP phosphorylase and ribose-1,5-bisphosphate isomerase functioning in an archaeal AMP metabolic pathway. J. Bacteriol. 194 (2012) 6847-6855. [PMID: 23065974]
3. Nakamura, A., Fujihashi, M., Aono, R., Sato, T., Nishiba, Y., Yoshida, S., Yano, A., Atomi, H., Imanaka, T. and Miki, K. Dynamic, ligand-dependent conformational change triggers reaction of ribose-1,5-bisphosphate isomerase from Thermococcus kodakarensis KOD1. J. Biol. Chem. 287 (2012) 20784-20796. [PMID: 22511789]
Accepted name: 5-deoxy-glucuronate isomerase
Reaction: 5-deoxy-D-glucuronate = 5-dehydro-2-deoxy-D-gluconate
For diagram of reaction click here.
Glossary: 5-dehydro-2-deoxy-D-gluconate = 2-deoxy-D-threo-hex-5-ulosonic acid
5-deoxy-D-glucuronate = 5-deoxy-D-xylo-hexuronic acid
Other name(s): 5DG isomerase; IolB
Systematic name: 5-deoxy-D-glucuronate aldose-ketose-isomerase
Comments: The enzyme, found in the bacterium Bacillus subtilis, is part of a myo-inositol degradation pathway leading to acetyl-CoA.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Yoshida, K., Yamaguchi, M., Morinaga, T., Kinehara, M., Ikeuchi, M., Ashida, H. and Fujita, Y. myo-Inositol catabolism in Bacillus subtilis. J. Biol. Chem. 283 (2008) 10415-10424. [PMID: 18310071]
Accepted name: sulfoquinovose isomerase
Reaction: (1) β-sulfoquinovose = 6-deoxy-6-sulfo-D-fructose
(2) β-sulfoquinovose = 6-sulfo-D-rhamnose
For diagram of reaction, click here
Glossary: sulfoquinovose = 6-deoxy-6-sulfo-D-glucopyranose
Other name(s): yihS (gene name)
Systematic name: 6-deoxy-6-sulfo-β-D-glucopyranose aldose-ketose-isomerase
Comments: The enzyme, characterized from the bacterium Escherichia coli, is involved in the degradation pathway of sulfoquinovose, the polar headgroup of sulfolipids found in the photosynthetic membranes of all higher plants, mosses, ferns, algae, and most photosynthetic bacteria, as well as the surface layer of some archaea.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
References:
1. Denger, K., Weiss, M., Felux, A.K., Schneider, A., Mayer, C., Spiteller, D., Huhn, T., Cook, A.M. and Schleheck, D. Sulphoglycolysis in Escherichia coli K-12 closes a gap in the biogeochemical sulphur cycle. Nature 507 (2014) 114-117. [PMID: 24463506]
2. Sharma, M., Abayakoon, P., Epa, R., Jin, Y., Lingford, J.P., Shimada, T., Nakano, M., Mui, J.W., Ishihama, A., Goddard-Borger, E.D., Davies, G.J. and Williams, S.J. Molecular basis of sulfosugar selectivity in sulfoglycolysis. ACS Cent. Sci. 7 (2021) 476-487. [PMID: 33791429]
Accepted name: (4S)-4-hydroxy-5-phosphooxypentane-2,3-dione isomerase
Reaction: (4S)-4-hydroxy-5-phosphooxypentane-2,3-dione = 3-hydroxy-5-phosphooxypentane-2,4-dione
Glossary: (4S)-4,5-dihydroxypentane-2,3-dione = autoinducer 2 = AI-2
Other name(s): lsrG (gene name); phospho-AI-2 isomerase; (4S)-4-hydroxy-5-phosphonooxypentane-2,3-dione isomerase; (4S)-4-hydroxy-5-phosphonooxypentane-2,3-dione aldose-ketose-isomerase
Systematic name: (4S)-4-hydroxy-5-phosphooxypentane-2,3-dione aldose-ketose-isomerase
Comments: The enzyme participates in a degradation pathway of the bacterial quorum-sensing autoinducer molecule AI-2.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
References:
1. Xavier, K.B., Miller, S.T., Lu, W., Kim, J.H., Rabinowitz, J., Pelczer, I., Semmelhack, M.F. and Bassler, B.L. Phosphorylation and processing of the quorum-sensing molecule autoinducer-2 in enteric bacteria. ACS Chem. Biol. 2 (2007) 128-136. [PMID: 17274596]
2. Marques, J.C., Lamosa, P., Russell, C., Ventura, R., Maycock, C., Semmelhack, M.F., Miller, S.T. and Xavier, K.B. Processing the interspecies quorum-sensing signal autoinducer-2 (AI-2): characterization of phospho-(S)-4,5-dihydroxy-2,3-pentanedione isomerization by LsrG protein. J. Biol. Chem. 286 (2011) 18331-18343. [PMID: 21454635]
Accepted name: L-erythrulose-1-phosphate isomerase
Reaction: L-erythrulose 1-phosphate = D-erythrulose 4-phosphate
Other name(s): eryH (gene name)
Systematic name: L-erythrulose-1-phosphate isomerase
Comments: The enzyme, characterized from the pathogenic bacterium Brucella abortus, which causes brucellosis in livestock, participates in erythritol catabolism.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Barbier, T., Collard, F., Zuniga-Ripa, A., Moriyon, I., Godard, T., Becker, J., Wittmann, C., Van Schaftingen, E. and Letesson, J.J. Erythritol feeds the pentose phosphate pathway via three new isomerases leading to D-erythrose-4-phosphate in Brucella. Proc. Natl. Acad. Sci. USA 111 (2014) 17815-17820. [PMID: 25453104]
Accepted name: D-erythrulose-4-phosphate isomerase
Reaction: D-erythrulose 4-phosphate = D-erythrose 4-phosphate
Other name(s): eryI (gene name)
Systematic name: D-erythrulose-4-phosphate ketose-aldose isomerase
Comments: The enzyme, characterized from the pathogenic bacterium Brucella abortus, which causes brucellosis in livestock, participates in erythritol catabolism.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Barbier, T., Collard, F., Zuniga-Ripa, A., Moriyon, I., Godard, T., Becker, J., Wittmann, C., Van Schaftingen, E. and Letesson, J.J. Erythritol feeds the pentose phosphate pathway via three new isomerases leading to D-erythrose-4-phosphate in Brucella. Proc. Natl. Acad. Sci. USA 111 (2014) 17815-17820. [PMID: 25453104]
Accepted name: 2-dehydrotetronate isomerase
Reaction: (1) 2-dehydro-L-erythronate = 3-dehydro-L-erythronate
(2) 2-dehydro-D-erythronate = 3-dehydro-D-erythronate
For diagram of reaction click here.
Glossary: L-erythronate = (2S,3S)-2,3,4-trihydroxybutanoate
D-erythronate = (2R,3R)-2,3,4-trihydroxybutanoate
Other name(s): otnI (gene name)
Systematic name: 2-dehydrotetronate isomerase
Comments: The enzyme, characterized from bacteria, is involved in D-erythronate and L-threonate catabolism.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
References:
1. Zhang, X., Carter, M.S., Vetting, M.W., San Francisco, B., Zhao, S., Al-Obaidi, N.F., Solbiati, J.O., Thiaville, J.J., de Crecy-Lagard, V., Jacobson, M.P., Almo, S.C. and Gerlt, J.A. Assignment of function to a domain of unknown function: DUF1537 is a new kinase family in catabolic pathways for acid sugars. Proc. Natl Acad. Sci. USA 113 (2016) E4161-E4169. [PMID: 27402745]
Accepted name: D-apiose isomerase
Reaction: D-apiose = apulose
Glossary: apulose = 1,3,4-trihydroxy-3-(hydroxymethyl)butan-2-one
Other name(s): apsI (gene name)
Systematic name: D-apiose isomerase
Comments: The enzyme, characterized from several bacterial species, is involved in a catabolic pathway for D-apiose.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
References:
1. Carter, M.S., Zhang, X., Huang, H., Bouvier, J.T., Francisco, B.S., Vetting, M.W., Al-Obaidi, N., Bonanno, J.B., Ghosh, A., Zallot, R.G., Andersen, H.M., Almo, S.C. and Gerlt, J.A. Functional assignment of multiple catabolic pathways for D-apiose. Nat. Chem. Biol. 14 (2018) 696-705. [PMID: 29867142]
Accepted name: 4-deoxy-4-sulfo-D-erythrose isomerase
Reaction: 4-deoxy-4-sulfo-D-erythrose = 4-deoxy-4-sulfo-D-erythrulose
Other name(s): sqwI (gene name)
Systematic name: 4-deoxy-4-sulfo-D-erythrose ketose-aldose isomerase
Comments: The enzyme, characterized from the bacterium Clostridium sp. MSTE9, is involved in a D-sulfoquinovose degradation pathway.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Liu, J., Wei, Y., Ma, K., An, J., Liu, X., Liu, Y., Ang, E.L., Zhao, H. and Zhang, Y. Mechanistically diverse pathways for sulfoquinovose degradation in bacteria. ACS Catal. 11 (2021) 14740-14750.
Accepted name: phenylpyruvate tautomerase
Reaction: keto-phenylpyruvate = enol-phenylpyruvate
Other name(s): phenylpyruvic keto-enol isomerase
Systematic name: phenylpyruvate ketoenol-isomerase
Comments: Also acts on other arylpyruvates.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9023-54-5
References:
1. Blasi, F., Fragonmele, F. and Covelli, I. Thyroidal phenylpyruvate tautomerase. Isolation and characterization. J. Biol. Chem. 244 (1969) 4864-4870. [PMID: 5824560]
2. Knox, W.E. p-Hydroxyphenylpyruvate enol-keto tautomerase. Methods Enzymol. 2 (1955) 289-295.
3. Knox, W.E. and Pitt, B.M. Enzymic catalysis of the keto-enol tautomerization of phenylpyruvic acids. J. Biol. Chem. 225 (1957) 675-688.
Accepted name: oxaloacetate tautomerase
Reaction: keto-oxaloacetate = enol-oxaloacetate
Other name(s): oxalacetic keto-enol isomerase
Systematic name: oxaloacetate ketoenol-isomerase
Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 37318-45-9
References:
1. Annett, R.G. and Kosicki, G.W. Oxalacetate keto-enol tautomerase. Purification and characterization. J. Biol. Chem. 244 (1969) 2059-2067. [PMID: 5781999]
Accepted name: TDP-4-oxo-6-deoxy-α-D-glucose-3,4-oxoisomerase (dTDP-3-dehydro-6-deoxy-α-D-galactopyranose-forming)
Reaction: dTDP-4-dehydro-6-deoxy-α-D-glucopyranose = dTDP-3-dehydro-6-deoxy-α-D-galactopyranose
For diagram of reaction click here.
Other name(s): dTDP-6-deoxy-hex-4-ulose isomerase; TDP-6-deoxy-hex-4-ulose isomerase; FdtA
Systematic name: dTDP-4-dehydro-6-deoxy-α-D-glucopyranose:dTDP-3-dehydro-6-deoxy-α-D-galactopyranose isomerase
Comments: The enzyme is involved in the biosynthesis of dTDP-3-acetamido-3,6-dideoxy-α-D-galactose. Four moieties of α-D-rhamnose and two moities of 3-acetamido-3,6-dideoxy-α-D-galactose form the repeating unit of the glycan chain in the S-layer of the bacterium Aneurinibacillus thermoaerophilus.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Pfoestl, A., Hofinger, A., Kosma, P. and Messner, P. Biosynthesis of dTDP-3-acetamido-3,6-dideoxy-α-D-galactose in Aneurinibacillus thermoaerophilus L420-91T. J. Biol. Chem. 278 (2003) 26410-26417. [PMID: 12740380]
2. Davis, M.L., Thoden, J.B. and Holden, H.M. The x-ray structure of dTDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase. J. Biol. Chem. 282 (2007) 19227-19236. [PMID: 17459872]
Accepted name: TDP-4-oxo-6-deoxy-α-D-glucose-3,4-oxoisomerase (dTDP-3-dehydro-6-deoxy-α-D-glucopyranose-forming)
Reaction: dTDP-4-dehydro-6-deoxy-α-D-glucopyranose = dTDP-3-dehydro-6-deoxy-α-D-glucopyranose
For diagram of reaction click here.
Other name(s): TDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase (ambiguous); Tyl1a; dTDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase (ambiguous)
Systematic name: dTDP-4-dehydro-6-deoxy-α-D-glucopyranose:dTDP-3-dehydro-6-deoxy-α-D-glucopyranose isomerase
Comments: The enzyme is involved in biosynthesis of D-mycaminose.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
References:
1. Melancon, C.E., 3rd, Hong, L., White, J.A., Liu, Y.N. and Liu, H.W. Characterization of TDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase from the D-mycaminose biosynthetic pathway of Streptomyces fradiae: in vitro activity and substrate specificity studies. Biochemistry 46 (2007) 577-590. [PMID: 17209568]
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 ketoenol-isomerase
Systematic name: 5-(methylsulfanyl)-2,3-dioxopentyl phosphate ketoenol-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: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
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. [PMID: 14551435]
Accepted name: 2-hydroxymuconate tautomerase
Reaction: (2Z,4E)-2-hydroxyhexa-2,4-dienedioate = (3E)-2-oxohex-3-enedioate
For diagram of reaction click here.
Glossary: (2Z,4E)-2-hydroxyhexa-2,4-dienedioate = (2Z,4E)-2-hydroxymuconate
Other name(s): 4-oxalocrotonate tautomerase (misleading); 4-oxalocrotonate isomerase (misleading); cnbG (gene name); praC (gene name); xylH (gene name)
Systematic name: (2Z,4E)-2-hydroxyhexa-2,4-dienedioate ketoenol isomerase
Comments: Involved in the meta-cleavage pathway for the degradation of phenols, modified phenols and catechols. The enol form (2Z,4E)-2-hydroxyhexa-2,4-dienedioate is produced as part of this pathway and is converted to the keto form (3E)-2-oxohex-3-enedioate by the enzyme [6]. Another keto form, (4E)-2-oxohex-4-enedioate (4-oxalocrotonate), was originally thought to be produced by the enzyme [1,2] but later shown to be produced non-enzymatically [5].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Whitman, C.P., Aird, B.A., Gillespie, W.R. and Stolowich, N.J. Chemical and enzymatic ketonization of 2-hydroxymuconate, a conjugated enol. J. Am. Chem. Soc. 113 (1991) 3154-3162.
2. Whitman, C.P., Hajipour, G., Watson, R.J., Johnson, W.H., Jr., Bembenek, M.E. and Stolowich, N.J. Stereospecific ketonization of 2-hydroxymuconate by 4-oxalocrotonate tautomerase and 5-(carboxymethyl)-2-hydroxymuconate isomerase. J. Am. Chem. Soc. 114 (1992) 10104-10110.
3. Subramanya, H.S., Roper, D.I., Dauter, Z., Dodson, E.J., Davies, G.J., Wilson, K.S. and Wigley, D.B. Enzymatic ketonization of 2-hydroxymuconate: specificity and mechanism investigated by the crystal structures of two isomerases. Biochemistry 35 (1996) 792-802. [PMID: 8547259]
4. Stivers, J.T., Abeygunawardana, C., Mildvan, A.S., Hajipour, G., Whitman, C.P. and Chen, L.H. Catalytic role of the amino-terminal proline in 4-oxalocrotonate tautomerase: affinity labeling and heteronuclear NMR studies. Biochemistry 35 (1996) 803-813. [PMID: 8547260]
5. Wang, S.C., Johnson, W.H., Jr., Czerwinski, R.M., Stamps, S.L. and Whitman, C.P. Kinetic and stereochemical analysis of YwhB, a 4-oxalocrotonate tautomerase homologue in Bacillus subtilis: mechanistic implications for the YwhB- and 4-oxalocrotonate tautomerase-catalyzed reactions. Biochemistry 46 (2007) 11919-11929. [PMID: 17902707]
6. Kasai, D., Fujinami, T., Abe, T., Mase, K., Katayama, Y., Fukuda, M. and Masai, E. Uncovering the protocatechuate 2,3-cleavage pathway genes. J. Bacteriol. 191 (2009) 6758-6768. [PMID: 19717587]
Accepted name: ascopyrone tautomerase
Reaction: 1,5-anhydro-4-deoxy-D-glycero-hex-3-en-2-ulose = 1,5-anhydro-4-deoxy-D-glycero-hex-1-en-3-ulose
For diagram of reaction click here.
Glossary: ascopyrone M = 1,5-anhydro-4-deoxy-D-glycero-hex-3-en-2-ulose = (6S)-4-hydroxy-6-(hydroxymethyl)-2H-pyran-3(6H)-one
ascopyrone P = 1,5-anhydro-4-deoxy-D-glycero-hex-1-en-3-ulose = (2S)-5-hydroxy-2-(hydroxymethyl)-2H-pyran-4(3H)-one
Other name(s): ascopyrone isomerase; ascopyrone intramolecular oxidoreductase; 1,5-anhydro-D-glycero-hex-3-en-2-ulose tautomerase; APM tautomerase; ascopyrone P tautomerase; APTM
Systematic name: 1,5-anhydro-4-deoxy-D-glycero-hex-3-en-2-ulose Δ3-Δ1-isomerase
Comments: This enzyme catalyses one of the steps in the anhydrofructose pathway, which leads to the degradation of glycogen and starch via 1,5-anhydro-D-fructose [1,2]. The other enzymes involved in this pathway are EC 4.2.1.110 (aldos-2-ulose dehydratase), EC 4.2.1.111 (1,5-anhydro-D-fructose dehydratase) and EC 4.2.2.13 [exo-(1→4)-α-D-glucan lyase]. Ascopyrone P is an anti-oxidant [2].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
References:
1. Yu, S., Refdahl, C. and Lundt, I. Enzymatic description of the anhydrofructose pathway of glycogen degradation; I. Identification and purification of anhydrofructose dehydratase, ascopyrone tautomerase and α-1,4-glucan lyase in the fungus Anthracobia melaloma. Biochim. Biophys. Acta 1672 (2004) 120-129. [PMID: 15110094]
2. Yu, S. and Fiskesund, R. The anhydrofructose pathway and its possible role in stress response and signaling. Biochim. Biophys. Acta 1760 (2006) 1314-1322. [PMID: 16822618]
Accepted name: 4-oxalomesaconate tautomerase
Reaction: (1E)-4-oxobut-1-ene-1,2,4-tricarboxylate = (1E,3E)-4-hydroxybuta-1,3-diene-1,2,4-tricarboxylate
For diagram of reaction click here.
Glossary: (1E)-4-oxobut-1-ene-1,2,4-tricarboxylate = keto tautomer of 4-oxalomesaconate
(1E,3E)-4-hydroxybuta-1,3-diene-1,2,4-tricarboxylate = one of the enol tautomers of 4-oxalomesaconate
Other name(s): GalD
Systematic name: 4-oxalomesaconate keto—enol-isomerase
Comments: This enzyme has been characterized from the bacterium Pseudomonas putida KT2440 and is involved in the degradation pathway of syringate and 3,4,5-trihydroxybenzoate. It catalyses the interconversion of two of the tautomers of 4-oxalomesaconate, a reaction that can also occur spontaneously.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
References:
1. Nogales, J., Canales, A., Jimenez-Barbero, J., Serra, B., Pingarron, J.M., Garcia, J.L. and Diaz, E. Unravelling the gallic acid degradation pathway in bacteria: the gal cluster from Pseudomonas putida. Mol. Microbiol. 79 (2011) 359-374. [PMID: 21219457]