“…(i) Adenylate cyclase activity was found either in the pellet or in the supernatant fractions, depending on the methods used for cellFdisruption and fractionation. This activity was very low compared with the activity in intact cells or in toluene-treated cells (40,131,151,219,267), and decreased nonlinearly on dilution, perhaps indicating the dissociation of a protein complex (401). (ii) Only intact cells Qr cells permeabilized by toluene treatment retained the regulation of adenylate cyclase activity, as if a regulatory protein or subunit dissociates irreversibly on dilution (131).…”