IUBMB Enzyme Nomenclature


Accepted name: acetylenecarboxylate hydratase

Reaction: 3-oxopropanoate = propynoate + H2O

Other name(s): acetylenemonocarboxylate hydratase; alkynoate hydratase; acetylenemonocarboxylate hydrase; acetylenemonocarboxylic acid hydrase; malonate-semialdehyde dehydratase; 3-oxopropanoate hydro-lyase

Systematic name: 3-oxopropanoate hydro-lyase (propynoate-forming)

Comments: The reaction is effectively irreversible, favouring oxopropanoate (malonic semialdehyde) and its tautomers. Also acts on but-3-ynoate forming acetoacetate. The mechanism appears to involve hydration of the acetylene to 3-hydroxypropenoate, which will spontaneously tautomerize to 3-oxopropanoate. It is thus analogous to EC, acetylenedicarboxylate decarboxylase, in its mechanism.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9024-26-4


1. Van den Tweel, W.J.J. and De Bont, J.A.M. Metabolism of 3-butyn-1-ol by Pseudomonas BB1. J. Gen. Microbiol. 131 (1985) 3155-3162. [PMID: 16525953]

2. Yamada, E.W. and Jakoby, W.B. Enzymatic utilization of acetylenic compounds. II. Acetylenemonocarboxylic acid hydrase. J. Biol. Chem. 234 (1959) 941-945. [PMID: 13654296]

[EC created 1965, (EC created 1978, modified 1989, modified 2000, incorporated 2004) modified 2004]

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