ID 1.3.1.85 DE crotonyl-CoA carboxylase/reductase. AN CCR. AN crotonyl-CoA reductase (carboxylating). CA (2S)-ethylmalonyl-CoA + NADP(+) = (2E)-butenoyl-CoA + CO2 + NADPH. CC -!- The reaction is catalyzed in the reverse direction. CC -!- This enzyme, isolated from the bacterium Rhodobacter sphaeroides, CC catalyzes (E)-but-2-enoyl-CoA-dependent oxidation of NADPH in the CC presence of CO2. CC -!- When CO2 is absent, the enzyme catalyzes the reduction of (E)-but-2- CC enoyl-CoA to butanoyl-CoA, but with only 10% of maximal activity CC (relative to (E)-but-2-enoyl-CoA carboxylation). DR Q3IZ91, CCCR_CERS4 ; //