Isolation and characterization of a proteolytic factor from the venom of Vipera palaestinae

A proteolytic enzyme which is active on collagen and gelatin was isolated from the venom of Vipera palaestinae. The enzyme showed an optimal temperature of 45 degrees C and an optimal pH of 8.0. It was inhibited by snake blood serum, but not by EDTA or trypsin inhibitors. The enzyme was completely separated from one of the venom hemorrhagins, which accompanied it through the purification procedure. The possible evolution of hemorrhagins from proteolytic enzymes is discussed.