Abstract
The substrate specifioities of some glandular and plasma kallikreins, bovine trypsin and plasmin, and boar acrosin were investigated using five tripeptidyl-p-nitroanilides and ten arginine and lysine ester derivatives as substrates. Of the substrates examined, N-α-benzoyl-L-arginine methyl and ethyl esters (Bz-Arg-Me and Bz-Arg-Et) and N-α-acetyl-L-arginine methyl ester (Ac-Arg-Me) were the most effective for the pancreatic and intestinal kallikreins, while N-α-tosyl-L-arginine methyl ester (Tos-Arg-Me) and Bz-Arg-Me were effectives as substrates for the human salivary and guinea-pig coagulating gland kallikreins, respectively. Ac-Arg-Me and N-α-acetyl-glycyl-L-lysine methyl ester (Ac-Gly-Lys-Me) were also good substrates for the boar acrosin. All of the tripeptidyl-p-nitroanilide substrates examined were hydrolyzed relatively ineffeotively by glandular kallikreins and boar acrosin. However, D-valyl-L-leucyl-L-arginine-p-nitroanilide (Val-Leu-Arg-pNA) and D-prolyl-L-phenylalanyl-L-arginine-p-nitroanilide (Pro-Phe-Arg-pNA) were found to be moderately useful substrates for various kallikreins and related enzymes.
