Fig. 4

Effects of pH (a) and osmotic stress (b) on the growth of H. pylori. We tested the following strains: N6 wt, ∆htrA, complemented strains with wt htrA (∆htrA/htrA) and with proteolytically inactive variant of htrA (∆htrA/htrAS/A). For osmotic stress, bacteria were grown on GC agar plates for 6 days in the presence of sucrose (175 mM), NaCl (85 mM) or MgCl₂ (32 mM) at 37 or 39 °C. The experiments were performed in triplicates and representative examples are shown