Able to isomerize both 3-cis and 3-trans double bonds into the 2-trans form in a range of enoyl-CoA species (PubMed:24344334). Has a preference for 3-trans substrates (By similarity). a (3Z)-enoyl-CoA = a 4-saturated (2E)-enoyl-CoA a (3E)-enoyl-CoA = a 4-saturated (2E)-enoyl-CoA (3E)-nonenoyl-CoA = (2E)-nonenoyl-CoA (2E)-tetradecenoyl-CoA = (3Z)-tetradecenoyl-CoA (3E)-tetradecenoyl-CoA = (2E)-tetradecenoyl-CoA (3E)-octenoyl-CoA = (2E)-octenoyl-CoA (3Z)-octenoyl-CoA = (2E)-octenoyl-CoA Lipid metabolism; fatty acid beta-oxidation. Expressed in liver and kidney (at protein level). Acetylation of Lys-60 is observed in liver mitochondria from fasted mice but not from fed mice. In the C-terminal section; belongs to the enoyl-CoA hydratase/isomerase family. Truncated N-terminus.