The recombinant cysteine peptidases, cruzain from Trypanosoma cruziand fromLeishmania mexicana, are cathepsin L-like and characteristically endo-peptidases. In this study, we characterized the carboxydi-peptidase activities of these enzymes and compared them with those of human recombinant cathepsin B and cathep-sin L. The analysis used the internally quenched fluorescent peptide Abz-FRFK*-OH and some of its analogues, where Abz isortho-aminobenzoic acid and K* is (2,4-dinitrophe-nyl)-e-NH2-lysine. .
