Figure 8

Antibodies enriched for an oxidized MRP detect a candidate oxidized yeast protein. Lysates of log-phase yeast cells (BY4741 strain), including wild-type (WT) and MsrA/MsrB double knockout (MsrA/B) strains, were treated with H₂O₂, and 30 μg proteins were subjected to Western blot analysis with the antibodies raised against MRP3 that were enriched for the oxidized MRP4 as described in Materials and Methods. (A) Yeast lysates were incubated with (lanes 2 and 4) or without (lanes 1 and 3) 100 mM H₂O₂ for 1 h at 37°C. (B) Wild-type (BY4741) lysates were incubated without (lane 1) or with different concentrations of H₂O₂ (lanes 2 to 5) for 1 h at 37°C. The triangles represent increasing amounts of H₂O₂ in the oxidation reaction (5, 10, 50, or 100 mM).