IUBMB Enzyme Nomenclature


Accepted name: trans-2-decenoyl-[acyl-carrier protein] isomerase

Reaction: a trans-dec-2-enoyl-[acyl-carrier protein] = a cis-dec-3-enoyl-[acyl-carrier protein]

Other name(s): β-hydroxydecanoyl thioester dehydrase; trans-2-cis-3-decenoyl-ACP isomerase; trans-2,cis-3-decenoyl-ACP isomerase; trans-2-decenoyl-ACP isomerase; FabM

Systematic name: decenoyl-[acyl-carrier protein] Δ2-trans-Δ3-cis-isomerase

Comments: While the enzyme from Escherichia coli is highly specific for the 10-carbon enoyl-ACP, the enzyme from Streptococcus pneumoniae can also use the 12-carbon enoyl-ACP as substrate in vitro but not 14- or 16-carbon enoyl-ACPs [3]. ACP can be replaced by either CoA or N-acetylcysteamine thioesters. The cis-3-enoyl product is required to form unsaturated fatty acids, such as palmitoleic acid and cis-vaccenic acid, in dissociated (or type II) fatty-acid biosynthesis.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9030-80-2


1. Brock, D.J.H., Kass, L.R. and Bloch, K. β-Hydroxydecanoyl thioester dehydrase. II. Mode of action. J. Biol. Chem. 242 (1967) 4432-4440. [PMID: 4863740]

2. Bloch, K. Enzymatic synthesis of monounsaturated fatty acids. Acc. Chem. Res. 2 (1969) 193-202.

3. Marrakchi, H., Choi, K.H. and Rock, C.O. A new mechanism for anaerobic unsaturated fatty acid formation in Streptococcus pneumoniae. J. Biol. Chem. 277 (2002) 44809-44816. [PMID: 12237320]

4. Cronan, J.E., Jr. and Rock, C.O. Biosynthesis of membrane lipids. In: Neidhardt, F.C. (Ed.), Escherichia coli and Salmonella: Cellular and Molecular Biology, 2nd edn, vol. 1, ASM Press, Washington, DC, 1996, pp. 612-636.

[EC created 2006]

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