Journal of Veterinary Parasitology

Among the several proteases associated with host-parasite relationship in trypanosomes, cysteine protease is considered important for the survival of parasite and infliction of pathogenesis in the infected host. Following gelatin substrate sodium dodecyl sulphatepolyacrylamide gel electrophoresis (SDS-PAGE) analysis of purified Trypanosoma evansi under non-denaturing condition, protease activity was observed in the molecular range of 117, 94, 83, 62, 53, and 28 kDa. Specific inhibition of cysteine protease activity using L3-carboxy-2, 3-transepoxypropionyl-leucylamido (4-guanidino)-butane (E-64) resulted in prevention of substrate degradation at approximately 28kDa region and thereby confirming its identity as a cysteine protease. This is a first report of identification of cysteine protease from an Indian isolate of T. evansi.