SEPARATION OF AUTOPROTHROMBIN III FROM BOVINE PROTHROMBIN PREPARATIONS

Abstract

Purified prothrombin was activated by means of purified thrombin, Ac-globulin, calcium ions, and crude "cephalin." Thrombin and autoprothrombin III generated. The latter was isolated as a single component by the same methods found suitable for the isolation of autoprothrombin C. It contained no autoprothrombin C activity, but some generated spontaneously, and also in 25% sodium citrate solution. It may be that autoprothrombin C generally does not form in normal blood clotting unless tissue extracts are involved. This implies the possibility that the most potent procoagulant power in the genesis of thrombosis is derived from tissues.