The hydrolysis (deacylation) of enantiomeric substrates by the chemically modified enzymes decanoyl-alpha-chymotrypsin and decanoyl-trypsin was studied. Reaction activity for decanoyl-alpha-chymotrypsin was lower than that for the native enzyme, although intriguingly the enantioselectivity was markedly enhanced as compared with the native enzyme. In particular, the apparently complete enantioselective
Stereoisomers of specific chromogenic substrates for various enzymes were synthesized by a conventional solution method. Among them, Suc-L-Tyr-D-Leu-D-Phe-pNA was found to be an effective and specific inhibitor of α-chymotrypsin. However, Suc-L-Tyr-D-Leu-D-Phe-Pipe did not show any inhibitory effect on α-chymotrypsin. The role of the pNA moiety of the above stereoisomer was investigated, and it was found that the pNA moiety participated in binding with some part of the enzyme, resulting in the manifestation of the inhibitory activity.