| Abstract: | Using biospecific chromatography on polylysocephamide, a toxic phospholipase possessing a presynaptic effect on neuromuscular preparations was isolated from the venom of the giant hornet Vespa orientalis. The enzyme was shown to possess a high hydrolytic activity towards 1-acyllysophosphatidylcholine within a narrow pH range (pH optimum 7.5). The enzyme activity was suppressed by detergents of various chemical composition. Lysophospholipase caused an intensive hemolysis of washed human erythrocytes. The catalytic and hemolytic functions of the enzyme were sensitive to metal ions, however, in a different degree. Ca2+ and Mn2+ activated, while Cu2+ and Zn2+ inhibited the enzyme. Mg2+ and Sr2+ had no effect on the enzyme activity. |
