FIGURE 6.

SLO is responsible for disruption of the mitochondrial membrane and release of cytochrome c into the macrophage cytosol. A, SLO-dependent loss of TMRE staining demonstrates perturbation of mitochondrial membrane potential (t = 4 h). Experiments were performed in triplicate and repeated three times. LL, L. lactis; FCCP, carbonylcyanide p-(trifluoromethoxy)phenylhydrazone. B, Western blot of cytosols of macrophages infected with GAS ± SLO, L. lactis ± SLO, or purified SLO illustrates SLO-mediated release of cytochrome c from mitochondria. Actin serves as loading control. Experiments were performed in duplicate.