Cluster-forming property correlated with hemolytic activity by staphylococcal γ-hemolysin transmembrane pores.

Staphylococcal γ-hemolysin (Hlg) is a pore-forming toxin consisting of two separate components, LukF (34kDa) and Hlg2 (32kDa). Here we show that Hlg pores aggregate and form clusters on human erythrocyte membranes in association with increasing hemolytic activity. Quantitative analysis using transmission electron microscopy and image processing revealed that the formation of single pores and clusters is related to the release of potassium ions and of hemoglobin from erythrocytes, respectively. This is the first study to suggest a novel and unique property which can facilitate hemolysis by the cluster formation of Hlg pores.