Iron depletion enhances Sod2p activity in sdo1∆ cells. The designated strains were cultured in YPD medium containing where indicated (+BPS) 40 μM BPS. a The intracellular iron levels were examined as in Fig. 1. Data shown are from three independent experiments. b Growth was monitored by monitoring OD 600 nm at 21 hours. c Whole-cell lysates were analyzed for SOD activity by native gel electrophoresis and nitroblue tetrazolium staining. SOD1 and SOD2 indicate positions of active Cu/Zn-containing Sod1p and manganese-containing Sod2p respectively. Sod2p and Pgk1p polypeptides from the whole-cell lysates were analyzed by immunoblot (bottom panel). d Sod2p activity was quantitated and expressed as ratio of Sod2p activity/Pgk1p for each sample, normalized to WT = 1. e Quantitation of Sod2p protein levels normalized to Pgk1p abundance in each sample, with WT = 1. Results are from two independent experiments. Values are the mean + SD. ***P <0.001, **P <0.01, *P <0.05, and NS (not significant) determined using Student’s T-test compared between the means of two indicated groups.