Key enzyme for ketone body catabolism. Transfers the CoA moiety from succinate to acetoacetate. Formation of the enzyme-CoA intermediate proceeds via an unstable anhydride species formed between the carboxylate groups of the enzyme and substrate (By similarity). Probably play and important roles in the energy metabolism of spermatozoa. a 3-oxo acid + succinyl-CoA = a 3-oxoacyl-CoA + succinate Ketone metabolism; succinyl-CoA degradation; acetoacetyl-CoA from succinyl-CoA: step 1/1. Homodimer. Belongs to the 3-oxoacid CoA-transferase family.