Figure 2.

Assays for the survival of WT and recombinant M. smegmatis under H₂O₂ stress. The WT and recombinant mycobacterial strains were cultured to A₆₀₀ = 0.5 and treated with 9 mm H₂O₂ for 3 h. Cells were harvested and plated on 7H10 plates at 37 °C for 3–4 days for counting cfu. The survival percentages were calculated by cfu (with H₂O₂)/cfu (without H₂O₂) for each strain. Error bars represented the variant range of the data derived from three biological replicates. A, assays for the effects of devR, devS, and c-di-GMP on the mycobacterial survival under the stress of 9 mm H₂O₂. B, assays for the effects of the devR operon genes on the mycobacterial survival under 9 mm H₂O₂. The p values of the relative survival rate were calculated by two-tailed Student's t test using GraphPad Prism 5. Asterisks represent significant difference between two groups (*, p ≤ 0.05; **, p ≤ 0.01). WT represents the wildtype mycobacteria strain; OEydeH represents ydeH-overexpressing strain; ΔdevR represents devR-deleted strain; OEdevR represents devR-overexpressing strain; OEydeH/ΔdevR represents ydeH-overexpressing in ΔdevR strain; devR comp represents devR-complementation strain; ΔdevS represents devS-deleted strain; OEydeH/ΔdevS represents ydeH-overexpressing in ΔdevS strain; devS comp represents devS-complementation strain; OEMs5242 represents Ms5242-overexpressing strain; OEMs5243 represents Ms5243-overexpressing strain; OEMs5245 represents Ms5245-overexpressing strain; OEMs5246 represents Ms5246-overexpressing strain.