FIG. 3.

Lysis of platelets monitored on the basis of OD₆₀₀. The supernatants of 18-h bacterial cultures in TSB were mixed with platelets (10⁹ platelets/ml). Platelet lysis was monitored by measuring the decrease in the OD₆₀₀ over time (2). The medium and purified alpha-toxin served as the negative and positive controls, respectively. Symbols: diamonds, TSB control plus washed platelets; squares, RN6390 (supernatant) plus washed platelets; triangles, SigB (supernatant) plus washed platelets; circles, purified alpha-toxin (1 mg/ml) plus washed platelets.