Figure 4. sdh6Δ and sdh7Δ mutants are sensitive to oxidative stress.

(A) 10-fold serial dilutions of cells were spotted on SC media ± 2 mM paraquat with indicated carbon sources and incubated at 30°C. (B) Steady-state levels of proteins in mitochondria isolated from strains cultured in the presence of 2 mM paraquat. Yah1, ferredoxin of the mitochondrial matrix. (C) Aconitase activity specific to cis-aconitate conversion in isolated mitochondria. Data are shown as mean ± SD (N=3). (D) Pre-cultures grown up to late-log phase in YPD media were diluted 2-fold, followed by addition of 6 mM H₂O₂ and incubated for 2 h at 30°C. Cells were washed with sterile water and 10-fold serial dilutions were spotteed on YPD plate, followed by incubation at 30°C. (E) Enhanced respiratory growths of sdh6Δ mutants and sdh7Δ mutants with iron supplementation 10-fold serial dilutions of cells were spotted on SC media ± FeCl₂ or ZnCl₂ as concentrations indicated, and then incubated at 30°C.