Differentiation of tryptic enzymes based on enantiomeric specificity at the deacylation step

The chiral specificity of tryptic enzymes at their deacylation step has been determined for the first time by virtue of 'inverse substrates' carrying optically active acyl groups. Differentiation of tryptic enzymes was also successful with these substrates. The stability of acyl-thrombin is substantially higher than those of trypsin and plasmin when the (S)-dihydrocoumarilyl group is applied. This is in contrast to the result with its (R)-antipode in which all three enzymes are not differentiated. The use of chiral p-amidinophenyl esters is proposed as a versatile methodology for the design of specific inhibitors capable of discriminating among tryptic enzymes.