Reaction: (2S)-ethylmalonyl-CoA + NADP+ = (E)-but-2-enoyl-CoA + CO2 + NADPH + H+
Glossary: (E)-but-2-enoyl-CoA = crotonyl-CoA
Other name(s): CCR; crotonyl-CoA reductase (carboxylating)
Systematic name: (2S)-ethylmalonyl-CoA:NADP+ oxidoreductase (decarboxylating)
Comments: The reaction is catalysed in the reverse direction. This enzyme, isolated from the bacterium Rhodobacter sphaeroides, catalyses (E)-but-2-enoyl-CoA-dependent oxidation of NADPH in the presence of CO2. When CO2 is absent, the enzyme catalyses the reduction of (E)-but-2-enoyl-CoA to butanoyl-CoA, but with only 10% of maximal activity (relative to (E)-but-2-enoyl-CoA carboxylation).
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
References:
1. Erb, T.J., Berg, I.A., Brecht, V., Muller, M., Fuchs, G. and Alber, B.E. Synthesis of C5-dicarboxylic acids from C2-units involving crotonyl-CoA carboxylase/reductase: the ethylmalonyl-CoA pathway. Proc. Natl. Acad. Sci. USA 104 (2007) 10631-10636. [PMID: 17548827]
2. Erb, T.J., Brecht, V., Fuchs, G., Muller, M. and Alber, B.E. Carboxylation mechanism and stereochemistry of crotonyl-CoA carboxylase/reductase, a carboxylating enoyl-thioester reductase. Proc. Natl. Acad. Sci. USA 106 (2009) 8871-8876. [PMID: 19458256]