Fig. 3.

TlpB is required for chemotactic responses to HCl and synthetic DPD. (A) Western blot analysis of mG27 wild-type, ΔtlpB, and tlpB* isogenic strains with an antibody that recognizes a conserved region of all H. pylori chemoreceptors. (B) Chemotactic behaviour of the tlpB* complemented strain was assayed using the wet-mount assay in response to mock DPD, 0.1 M HCl and 0.1 mM synthetic DPD. (C) The normalized stopping frequency for mG27 wild-type, ΔtlpB and tlpB* isogenic strains treated with mock DPD, 0.1 M HCl and 0.1 mM synthetic DPD is shown, where the average number of stops for each strain in each condition is normalized to that strain’s average number of stops in mock DPD. The number of individual bacterial cells scored (n) for each condition is indicated below the column; bars indicate se. * indicates statistically significant differences in stopping frequency as compared to the mock DPD treatment of the same strain (P<0.001 with Bonferroni correction).