Figure 3.

Cytochrome c reductase activity of yeast Erv1 under anaerobic conditions. (A) Reduction at various concentrations (5–60 μm) of hhCytc by 1 mm DTT as measured by following the absorbance change at 550 nm, in the presence of 1 μm Erv1 and 10 units·mL⁻¹ of SOD. Erv1 was mixed with hhCytc in one syringe before mixing with DTT and SOD in another syringe using stopped‐flow equipment located inside an anaerobic chamber (O₂ < 2 p.p.m.; black lines). For comparison, the time courses of the reactions measured under normal aerobic conditions were shown (red lines). (B) As in A, but using ScCytc. (C, D) Michaelis–Menten plots of the results shown in A and B, respectively. The lines represent analysis using Michaelis–Menten equation. Error bars represent SEM, n = 3. All the enzyme kinetic parameters are summarised in Table 1.