Thioesterase that has relatively broad substrate specificity, hydrolyzing primarily medium- and long-chain acyl-CoA substrates to free fatty acids and CoA. Functions in the thioesterase-dependent pathway of beta-oxidation of oleate and conjugated linoleate ((9Z,11E)-octadecadienoate or CLA), which provides all energy and carbon precursors required for the growth of E.coli. Thus, supports growth on oleate or conjugated linoleate as the sole source of carbon by hydrolyzing 3,5-tetradecadienoyl-CoA, the terminal metabolite of oleate beta-oxidation via the alternative thioesterase-dependent pathway, and 3,5-dodecadienoyl-CoA, the end product of CLA beta-oxidation, respectively. Seems to be involved in 3-hydroxyalkanoate production in E.coli. a fatty acyl-CoA + H2O = a fatty acid + CoA + H(+) H2O + tetradecanoyl-CoA = CoA + H(+) + tetradecanoate (3E,5Z)-tetradecadienoyl-CoA + H2O = (3E,5Z)-tetradecadienoate + CoA + H(+) dodecanoyl-CoA + H2O = CoA + dodecanoate + H(+) (3Z,5E)-dodecadienoyl-CoA + H2O = (3Z,5E)-dodecadienoate + CoA + H(+) decanoyl-CoA + H2O = CoA + decanoate + H(+) H2O + octanoyl-CoA = CoA + H(+) + octanoate H2O + hexanoyl-CoA = CoA + H(+) + hexanoate H2O + pentanoyl-CoA = CoA + H(+) + pentanoate butanoyl-CoA + H2O = butanoate + CoA + H(+) 4-methylpentanoyl-CoA + H2O = 4-methylpentanoate + CoA + H(+) (3R)-3-hydroxypentanoyl-CoA + H2O = (3R)-3-hydroxypentanoate + CoA + H(+) (3S)-3-hydroxypentanoyl-CoA + H2O = (3S)-3-hydroxypentanoate + CoA + H(+) H2O + hexadecanoyl-CoA = CoA + H(+) + hexadecanoate H2O + octadecanoyl-CoA = CoA + H(+) + octadecanoate (9Z)-octadecenoyl-CoA + H2O = (9Z)-octadecenoate + CoA + H(+) (3R)-3-hydroxybutanoyl-CoA + H2O = (R)-3-hydroxybutanoate + CoA + H(+) (3S)-3-hydroxybutanoyl-CoA + H2O = (S)-3-hydroxybutanoate + CoA + H(+) (2E)-dodecenoyl-CoA + H2O = (2E)-dodecenoate + CoA + H(+) 3-oxododecanoyl-CoA + H2O = 3-oxododecanoate + CoA + H(+) 3-hydroxydodecanoyl-CoA + H2O = 3-hydroxydodecanoate + CoA + H(+) Homotetramer. Belongs to the C/M/P thioester hydrolase family.