TAMe Esterase Activity of Blood Thrombokinase after Repeated Electrophoretic Fractionations.

Abstract

Thrombokinase, purified from 738 liters of bovine plasma, was subjected to repeated fractionations by continuous flow paper electrophoresis. This increased the specific activity of the kinase and led to a 3d electrophoretic run which placed almost all the protein in a single peak. Kinase activity was closely accompanied by TAMe (tosylarginine methyl ester) esterase activity through successive stages of electrophoretic fractionation. The kinase fractions of the 3d run showed esterase activity of the order of 337 TAMe units/mg protein. The results are in accord with the view that TAMe is a substrate for thrombokinase and that thrombokinase is a trypsin-like enzyme.