Proteolytic Activities in Cell Extracts of Trypanosoma cruzi*

Abstract

Cell extracts of culture forms of T. cruzi are capable of hydrolyzing substances belonging to 4 different groups of protease substrates: substrates for trypsin-like enzymes: benzoyl-arginine-p-nitroanilide and benzoyl-arginine-naphtylamide; substrates for aminopeptidases.sbd.leucyl, lysyl and glutamyl-.beta.-naphtylamide; a substrate for chymotrypsin-like enzymes.sbd.carbobenzoxy-L-tyrosine-p-nitrophenylester, and a nonspecific substrate for a broad range of proteases.sbd.azocasein. Some physico-chemical characteristics of each enzymic reaction were studied. They were distinct enough to allow attributing each hydrolytic activity to a separate enzyme.