Figure 3.

(A) Rate of oxidation of reduced Cytc 10 s after the addition of 50 µM H₂O₂ (n = 7). (B) Rate of reduction of oxidized Cytc by superoxide produced in the presence of the hypoxanthine/xanthine oxidase reaction (n = 4–8). (C) Heme degradation of Cytc upon addition of excessive H₂O₂ (3 mM) was measured as a reduction of absorbance in the 408 nm Soret peak of Cytc (n = 3). (D) Liposomes containing 0%, 20%, 30%, and 50% of tetraoleoyl-cardiolipin (TOCL) were incubated in the presence of Cytc K53 variants. Cardiolipin peroxidase activity was determined in the presence of H₂O₂ and Cytc as a measure of resorufin fluorescence (n = 5). (E) Redox potential of K53 variants of Cytc were measured using the spectrophotometric method in the presence DCIP as a reference compound (n = 5). Data are represented as means ± SEM, * p < 0.05.