[Isolation of active preparation of Na+, K+-ATPase from cattle brain and study of the role of carboxyl, sulfhydryl and hydroxyl groups]

Abstract

A method is presented for obtaining the preparation of N+, K+-ATPase from the cattle brain. The specific activity of the preparation is 5 units (mu mole Pi per 1 min) per 1 mg of protein. A water-soluble derivate of carbodiimide is shown to inhibit reversibly both Na+, K+-ATPase and K+-phosphatase. ATP, Na+ and K+ manifest a protective effect against inhibition, and Na+ and K+ revealed a competition with the inhibitor for the enzyme. p-Chloromercuribenzoate inhibits irreversibly Na+, K+-ATPase and K+-phosphatase activities. The substrates ATP and p-nitrophenylphosphate protected these activities against inhibition. The phosphororganic compound O-n-butyl-S-(beta-ethyl-mercaptoethyl)-methyl thiophosphate has no significant effect on the Na+, K+-ATPase and K+-phosphatase activities.