Double-reciprocal plot of succinyl-CoA:benzylsuccinate CoA-transferase activity versus succinate concentration. The assays were performed by the standard luminometric assay in the presence of 5 (a), 15 (b), 30 (c), 60 (d), or 120 (e) μM concentrations of a chemically synthesized regioisomer mixture of 2- and 3-(R)-benzylsuccinyl-CoA (molar ratio, 2:1). Reactions were started with the indicated concentrations of succinate. The symbols represent mean values of two measurements.