Partial Resolution of the Enzymes Catalyzing Oxidative Phosphorylation

Abstract

Abstract 1. The properties of a mitochondrial fraction (F0) which confers oligomycin sensitivity on soluble ATPase were found to resemble in several aspects the properties of particles that catalyze oxidative phosphorylation. Susceptibility to oligomycin, Dio-9, tri-n-butyltin chloride, detergents, and phospholipase A are shared by both systems. 2. Treatment of F0 with phospholipase A resulted in complete loss of activity. About half of the original activity was restored by treatment of the preparation with serum albumin and phospholipids. 3. Brief exposure of particles containing F0 activity to trypsin or to sonic oscillation either at pH 10.0 or in the presence of phospholipid resulted in partial loss of F0 activity. Full restoration of activity was achieved by addition of coupling factor 4.