Purification and characteristics of hydrophobic membrane protein(s) required for DCCD sensitivity of ATPase in Mycobacterium phlei.

The energy-transducing N,N'-dicyclohexylcarbodiimide-sensitive (DCCD-sensitive) ATPase complex consists of two parts, a soluble catalytic protein (F1), and an intrinsic membrane protein (F0). The bacterial coupling factor complex, BCF0-BCF1, has recently been purified from Mycobacterium phlei, and used to reconstitute oxidative phosphorylation in detergent-extracted membranes. The BCF0 moiety has been purified by being recovered from the purified BCF0-BCF1 complex by affinity chromatography. BCF0 is a lipoprotein or lipoprotein complex with an approximate molecular weight of 60,000. The preparation contained 0.15 mg of phospholipid per milligram protein. There appear to be three polypeptides, with approximate molecular weights of 24,000, 18,000, and 8,000 as determined by sodium dodecylsulfate acrylamide gel electrophoresis. Purified BCF0 conferred DCCD sensitivity on a purified BCF1 preparation. Reconstitution of oxidative phosphorylation was achieved after incubation of detergent-extracted membranes with purified BCF0 and purified BCF1.