FURTHER CHARACTERIZATION of BOTHROPAIN, A CYSTEINE PEPTIDASE FROM the PLASMA of the SNAKE BOTHROPS-JARARACA

Abstract

1. A new procedure was developed for the isolation of bothropain from Bothrops jararaca plasma. the previously used proteolytic digestion step was abolished and HPLC was introduced for the final purification.2. Comparison of enzyme preparations obtained by the two procedures demonstrated a weak proteolysis of bothropain by trypsin, which had no effect on its catalytic properties.3. the primary specificity of bothropain for basic amino acids was confirmed and extended to the S-benzyl-cysteinyl residue. the enzyme showed a strong specificity for hydrophobic groups at P2, with a marked preference for Leu over Phe. No hydrolysis of oxidized insulin B chain by bothropain was detected. Binding of peptidyl diazomethane was also favored by hydrophobic residues at P2 but a restricted specificity for P1 was not observed.4. the catalytic properties, and the inhibition pattern by diazomethanes, indicate a similarity between bothropain and cathepsin L.