IUBMB Enzyme Nomenclature


Accepted name: branched-chain-2-oxoacid decarboxylase

Reaction: (3S)-3-methyl-2-oxopentanoate = 2-methylbutanal + CO2

Other name(s): branched-chain oxo acid decarboxylase; branched-chain alpha-keto acid decarboxylase; branched-chain keto acid decarboxylase; BCKA; (3S)-3-methyl-2-oxopentanoate carboxy-lyase

Systematic name: (3S)-3-methyl-2-oxopentanoate carboxy-lyase (2-methylbutanal-forming)

Comments: Acts on a number of 2-oxo acids, with a high affinity towards branched-chain substrates. The aldehyde formed may be enzyme-bound, and may be an intermediate in the bacterial system for the biosynthesis of branched-chain fatty acids.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 63653-19-0


1. Oku, H. and Kaneda, T. Biosynthesis of branched-chain fatty acids in Bacillus subtilis. A decarboxylase is essential for branched-chain fatty acid synthetase. J. Biol. Chem. 263 (1988) 18386-18396. [PMID: 3142877]

2. de la Plaza, M., Fernandez de Palencia, P., Pelaez, C. and Requena, T. Biochemical and molecular characterization of α-ketoisovalerate decarboxylase, an enzyme involved in the formation of aldehydes from amino acids by Lactococcus lactis. FEMS Microbiol. Lett. 238 (2004) 367-374. [PMID: 15358422]

3. Smit, B.A., van Hylckama Vlieg, J.E., Engels, W.J., Meijer, L., Wouters, J.T. and Smit, G. Identification, cloning, and characterization of a Lactococcus lactis branched-chain α-keto acid decarboxylase involved in flavor formation. Appl. Environ. Microbiol. 71 (2005) 303-311. [PMID: 15640202]

[EC created 1990]

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