Purification of a capillary permeability-increasing enzyme-2 from the venom of Agkistrodon caliginosus (Kankoku-Mamushi).

A capillary permeability-increasing enzyme-2 was purified from the venom of A. caliginosus by ion-exchange chromatography and gel filtration on Sephadex G-100. By this procedure, 3.1 mg of purified enzyme was obtained from 4 g of the venom. The mol. wt of the purified enzyme was estimated to be approximately 44,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme hydrolyzed N-alpha-tosyl-L-arginine methylester with a specific activity of 56.5 units/mg of protein, and did not show any caseinolytic, clotting or bradykinin-releasing activity. When 13.9 micrograms of the enzyme was injected into the depilated skin on the back of a rabbit, capillary permeability was increased.