IUBMB Enzyme Nomenclature


Accepted name: 4-hydroxy-4-methyl-2-oxoglutarate aldolase

Reaction: (1) 4-hydroxy-4-methyl-2-oxoglutarate = 2 pyruvate
(2) 2-hydroxy-4-oxobutane-1,2,4-tricarboxylate = oxaloacetate + pyruvate

For diagram of reaction click here.

Other name(s): pyruvate aldolase; γ-methyl-γ-hydroxy-α-ketoglutaric aldolase; 4-hydroxy-4-methyl-2-ketoglutarate aldolase; 4-hydroxy-4-methyl-2-oxoglutarate pyruvate-lyase; HMG aldolase; CHA aldolase; 4-carboxy-4-hydroxy-2-oxoadipate aldolase

Systematic name: 4-hydroxy-4-methyl-2-oxoglutarate pyruvate-lyase (pyruvate-forming)

Comments: Requires a divalent metal ion [3]. This enzyme participates in the degradation of 3,4-dihydroxybenzoate (via the meta-cleavage pathway), phthalate, syringate and 3,4,5-trihydroxybenzoate [1-3]. The enzyme from Pseudomonas straminea can also catalyse the activity of EC, 4-hydroxy-2-oxoglutarate aldolase, and the decarboxylation of oxaloacetate [3].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37290-65-6


1. Tack, B.F., Chapman, P.J. and Dagley, S. Purification and properties of 4-hydroxy-4-methyl-2-oxoglutarate aldolase. J. Biol. Chem. 247 (1972) 6444-6449. [PMID: 5076765]

2. Wood, W.A. 2-Keto-3-deoxy-6-phosphogluconic and related aldolases. In: Boyer, P.D. (Ed.), The Enzymes, 3rd edn, vol. 7, Academic Press, New York, 1972, pp. 281-302.

3. Maruyama, K. Purification and properties of 4-hydroxy-4-methyl-2-oxoglutarate aldolase from Pseudomonas ochraceae grown on phthalate. J. Biochem. 108 (1990) 327–333. [PMID: 2229032]

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 1972, modified 2012]

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