Two Predicted Chemoreceptors of Helicobacter pyloriPromote Stomach Infection

ABSTRACTHelicobacter pylorimust be motile or display chemotaxis to be able to fully infect mammals, but it is not known how this chemotaxis is directed. We disrupted two genes encoding predicted chemoreceptors, tlpAand tlpC. H. pylorimutants lacking either of these genes are fully motile and chemotactic in vitro and are as able as the wild type to infect mice when they are the sole infecting strains. In contrast, when mice are coinfected with the H. pyloriSS1 tlpAor tlpCmutant and the wild type, we find more wild type than mutant after 2 weeks of colonization. Neither strain has an in vitro growth defect. These results suggest that the tlpA- and tlpC-encoded proteins assist colonization of the stomach environment.