Shows trans-enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydratase activity (PubMed:19136596, PubMed:20511508). Displays a broad chain length specificity, with a predilection for the C8 to C12 substrates (PubMed:20511508). a (3R)-3-hydroxyacyl-CoA = a (2E)-enoyl-CoA + H2O (2E)-octenoyl-CoA + H2O = (3R)-hydroxyoctanoyl-CoA (3R)-3-hydroxydodecanoyl-CoA = (2E)-dodecenoyl-CoA + H2O (3R)-hydroxyhexadecanoyl-CoA = (2E)-hexadecenoyl-CoA + H2O (3R)-hydroxyeicosanoyl-CoA = (2E)-eicosenoyl-CoA + H2O (3R)-3-hydroxybutanoyl-CoA = (2E)-butenoyl-CoA + H2O Deletion of the gene does not affect the biosynthesis of all three types of mycolic acid. Belongs to the enoyl-CoA hydratase/isomerase family.