Subunit interaction in the mitochondrial H+-translocating ATPase. Association of the 26,500-dalton atpase binding protein and oligomycin sensitivity conferral protein with F1-ATPase

The rat liver 26,500-dalton ATPase binding protein and beef heart oligomycin sensitivity conferral protein are able to interact with the rat liver Type II ATPase to form discrete complexes. The equilibrium constants for these interactions are similar and each forms a 1:1 complex with the ATPase. The reassociated complex of Type II ATPase and 26,500-dalton ATPase binding protein or of oligomycin sensitivity conferral protein and Type II ATPase has properties similar to that of Type I ATPase. Dimerization of oligomycin sensitivity conferral protein by oxidation with copper phenanthroline chelate abolishes its ability to interact with the Type II ATPase. The isoelectric point and amino acid composition of the 26,500-dalton ATPase binding protein and oligomycin sensitivity conferral protein are similar. The polypeptide patterns produced by cyanogen bromide cleavage indicates a similar but nonidentical pattern to the 26,500-dalton ATPase binding protein and the oligomycin sensitivity conferral protein.