IUBMB Enzyme Nomenclature


Accepted name: acetylene hydratase

Reaction: acetaldehyde = acetylene + H2O

Other name(s): AH; acetaldehyde hydro-lyase

Systematic name: acetaldehyde hydro-lyase (acetylene-forming)

Comments: This is a non-redox-active enzyme that contains two molybdopterin guanine dinucleotide (MGD) cofactors, a tungsten centre and a cubane type [4Fe-4S] cluster [2]. The tungsten centre binds a water molecule that is activated by an adjacent aspartate residue, enabling it to attack acetylene bound in a distinct hydrophobic pocket [2]. Ethylene cannot act as a substrate [1].

Links to other databases: BRENDA, EAWAG-BBD, EXPASY, KEGG, Metacyc, PDB, CAS registry number:


1. Rosner, B.M. and Schink, B. Purification and characterization of acetylene hydratase of Pelobacter acetylenicus, a tungsten iron-sulfur protein. J. Bacteriol. 177 (1995) 5767-5772. [PMID: 7592321]

2. Seiffert, G.B., Ullmann, G.M., Messerschmidt, A., Schink, B., Kroneck, P.M. and Einsle, O. Structure of the non-redox-active tungsten/[4Fe:4S] enzyme acetylene hydratase. Proc. Natl. Acad. Sci. USA 104 (2007) 3073-3077. [PMID: 17360611]

[EC created 2007]

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