Figure 6.

Fsq heightens resistance to hydrogen peroxide. a, challenge of WT compared with Δfsq with 20 or 50 mm hydrogen peroxide for 3 h. Cells were grown aerobically in HdB with 22 mm glycerol for 10 days before harvest and resuspension in phosphate buffer saline with 0.5% tyloxapol. Cells were normalized to 1 optical density (600 nm) before treatment. b, challenge of WT compared with Δfsq with 20 or 50 mm hydrogen peroxide for 3 h. Cells were grown hypoxically in HdB with 22 mm glycerol for 10 days before harvest and resuspension in phosphate buffer saline with 0.5% tyloxapol. Cells were normalized to 1 optical density (600 nm) before treatment. c, challenge of WT either expressing fsq (fsq⁺) (WT pLH2) or a vector control (VC) (WT pMind) control induced with 20 ng⁻¹ ml tetracycline, challenged with 50 or 75 mm hydrogen peroxide for 3 h. Cells were grown aerobically to exponential phase n HdB with 22 mm glycerol before harvest and resuspension in phosphate buffer saline with 0.5% tyloxapol. Cells were normalized to 1 optical density (600 nm) before treatment. a–c, error bars represent S.D. of three biological replicates. Unpaired Student's t test compared with WT for each treatment, where *, p < 0.05; **, p < 0.01.