Studies on diphosphopyridine nucleotidase and platelet damaging factor in an extracellular product of Listeria monocytogenes.

Abstract

Hemolysin preparations from a virulent strain of Listeria monocytogenes were chromatographed on Sephadex G-100 and Sephadex DEAE A-50 columns. Three types of activities were identified: DPNase activity, hemolytic activity, and platelet-damaging activity. The separation of the peak with DPN-destroying activity from the peaks with hemolytic and platelet-damaging activities provided evidence that the factor in the solutions responsible for the destruction of DPN was distinct from that causing hemolysis and platelet-damage. The DPNase factor was found to be non-dialyzable, to be heat labile, and to have optimal activity in the pH range of 6.8–7.4.