Figure 3.

Effect of H₂O₂ on partial reactions of ETC. Triton-solubilized mitochondria were incubated during 30 min at 4°C in 50 mm KH₂PO₄ buffer with indicated concentrations of H₂O₂ under conditions described in Materials and methods. Succinate-DCIP oxidoreductase (A), succinate-cytochrome c oxidoreductase (B), cytochrome oxidase (C) or cytochrome c oxidase (D) activities were measured as described in Materials and methods. Results are expressed as the mean±SE of >3 independent experiments. Significantly different when compared to control (0 mm H₂O₂) (*p<0.05, **p<0.01).