IUBMB Enzyme Nomenclature


Accepted name: 4-oxalomesaconate hydratase

Reaction: 2-hydroxy-4-oxobutane-1,2,4-tricarboxylate = (1E,3E)-4-hydroxybuta-1,3-diene-1,2,4-tricarboxylate + H2O

For diagram of reaction click here.

Other name(s): 4-carboxy-2-oxohexenedioate hydratase; 4-carboxy-2-oxobutane-1,2,4-tricarboxylate 2,3-hydro-lyase; oxalmesaconate hydratase; γ-oxalmesaconate hydratase; 2-hydroxy-4-oxobutane-1,2,4-tricarboxylate 2,3-hydro-lyase; LigJ; GalB; 4-oxalmesaconate hydratase

Systematic name: (1E,3E)-4-hydroxybuta-1,3-diene-1,2,4-tricarboxylate 1,2-hydro-lyase (2-hydroxy-4-oxobutane-1,2,4-tricarboxylate-forming)

Comments: This enzyme participates in the degradation of protocatechuate (via the meta-cleavage pathway), syringate and gallate, catalysing the reaction in the opposite direction [1-3]. It accepts the enol-form of 4-oxalomesaconate, 2-hydroxy-4-carboxy-hexa-2,4-dienedioate [4].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 85204-95-1


1. Maruyama, K. Enzymes responsible for degradation of 4-oxalmesaconic acid in Pseudomonas ochraceae. J. Biochem. 93 (1983) 567-574. [PMID: 6841354]

2. Maruyama, K. Purification and properties of γ-oxalomesaconate hydratase from Pseudomonas ochraceae grown with phthalate. Biochem. Biophys. Res. Commun. 128 (1985) 271-277. [PMID: 3985968]

3. Hara, H., Masai, E., Katayama, Y. and Fukuda, M. The 4-oxalomesaconate hydratase gene, involved in the protocatechuate 4,5-cleavage pathway, is essential to vanillate and syringate degradation in Sphingomonas paucimobilis SYK-6. J. Bacteriol. 182 (2000) 6950-6957. [PMID: 11092855]

4. 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]

[EC created 1986, modified 2011]

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