Studies on the Mitochondrial Adenosine Triphosphatase System

When phosphorylating submitochondrial electron transport particles (ETPh) are extracted with 2 m NaCl, the residue becomes deficient in adenosine triphosphatase activity and in the capacity to catalyze ATP-energized reactions. A restoration of these capacities can be achieved with the salt-free extract, which is devoid of ATPase activity. Electrophoretic evidence indicates that the salt-free extract is a mixture of subunits of the mitochondrial ATPase (F1). Additional studies have established that subunits of F1, obtained by depolymerizing F1 in the presence of salt at 0°, can substitute for the salt extract in the restoration of ATPase activity and the capability of catalyzing ATP-energized reactions in the salt-extracted particles.