Studies on the proteinase of Clostridium histolyticum

Abstract

The proteinase of Cl. histolyticum is most active at pH 7, both in the presence and absence of added activators. The proteinase is activated by sulphydryl compounds, but not by the tryptic activator, enterokinase. The activation produced by sulphydryl compounds can be considerably increased by Fe++, Mn++, Ni++, Cu++ and Co++. All except Co++ produce activation at very low metal ion concn. The maximum activation is obtained under anaerobic conditions. The active group in the enzyme is probably not [long dash]SH, since iodoacetic acid does not inhibit its activity. H2O2 in high concentrations inhibits irreversibly. The quantity of proteinase present in a culture medium increases rapidly to a maximum during the early stages of bacterial growth (24 hr.), then decreases to a low value. The quantity of aminopolypeptidase increases steadily throughout the incubation period. These enzymes are probably secreted directly by the living bacteria.