Abstract
GTP and AIF4- significantly stimulated the late phosphatidic acid (PA) formation induced by Clostridium perfringens alpha-toxin in rabbit erythrocyte lysates. Pertussis toxin blocked the PA production. AIF4- markedly enhanced phosphatidylethanol production induced by alpha-toxin in the presence of ethanol. GTP[gamma S] stimulated the PA formation and hemolysis induced by alpha-toxin, and GDP[beta S] inhibited them. An H-to-G mutation at position 126 (H126G) induced the PA formation and hemolysis in a Co2+ concentration-dependent manner. H148G induced neither the PA formation nor hemolysis. These results suggest that the toxin-induced hemolysis is due to activation of phospholipid metabolism systems through GTP-binding protein.