Standardization of Chromogenic Synthetic Peptide Substrates for Proteolytic Enzymes

Chromogenic substrates Proteolytic enzymes Lars Svendsen, Pentapharm AG, PO Box, CH-4002 Basel (Switzerland) Methods using synthetic substrates for assaying enzyme activities are easy and comfortable to perform. Results obtained may, however, differ from place to place and time to time, due to differences of the substrate preparations and of their use. The enzymatic hydrolyzable substrate content in the so-called ‘substrate preparations’ have to be known. Only then a correct concentration of digestable substrate can be made. This is of fundamental importance when Km and V∏‚i‚x are established for a special enzyme-substrate system. But it is also of great importance to know the exact assaying conditions with respect to the correct substrate concentration, temperature, pH, ionic strength as well as the composition of the buffer used, to obtain comparable results from different laboratories. The impurities or ballast of the substrate preparations should not have any influence on the enzymatic katalytic properties, neither activate nor inhibit.