The Plasminogen Activator of Vampire Bat Saliva

Abstract

Abstract A procedure is described for the production of a highly active plasminogen activator (desmokinase) from the saliva of the vampire bat using gel filtration on Biogel A 0.5 m followed by ion-exchange chromatography on DEAE-cellulose. Investigations using specific inhibitors indicated that desmokinase was probably a specific protease similar in some respect to urokinase. Desmokinase was not, however, able to activate plasminogen in solution, and it is postulated that this could be due to a requirement for a fibrin surface for activation to proceed. Desmokinase seems to be more effective than either urokinase or streptokinase in the lysis of preformed blood clots. This property may be explicable in terms of greater affinity of desmokinase for fibrin.