FIG 4.

Mutant phenotypic assays for growth and survival. Growth (A) and survival assays (B and C) of wild type (WT), ΔaptC, and ΔatpF. (A) Bacteria were treated with 100 mM propionate, 3% NaCl, and 1 mM H₂O₂ in LB, and growth (OD₆₀₀) was measured at 6 h. (B) Bacteria were starved for 4 (t₁) days and 7 (t₁) days in 1× PBS. Viable bacteria counts were enumerated by plating serial dilutions on LB agar plates. (C) Bacteria were incubated in glycine-HCl buffer (pH 3.0) and incubated for 1, 1.5, and 2 h. Viable cells were enumerated by plating serial dilutions. Bar represents mean ± SE. All of the above-described experiments were performed in ≥3 replicates. Statistical analysis was performed using one-way analysis of variance (ANOVA) with correcting for multiple comparisons using the Holm-Sidak method; *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001.