POSTERS - BLAST X - University of Utah
POSTERS - BLAST X - University of Utah
POSTERS - BLAST X - University of Utah
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<strong>BLAST</strong> X Poster #54<br />
ANALYSIS OF HELICOBACTER PYLORI LACKING ALL FOUR CHEMORECEPTORS<br />
Karen M. Ottemann<br />
UC Santa Cruz<br />
Helicobacter pylori is an epsilon proteobacter that uses chemotaxis and motility to infect<br />
human stomachs and cause ulcer disease. Based on genome sequencing and annotation, H.<br />
pylori is predicted to have four chemoreceptors. Here we describe the construction and<br />
characterization <strong>of</strong> mutants lacking one, two, three, or all four chemoreceptors in strain mG27,<br />
and a comparison <strong>of</strong> chemoreceptor expression across many H. pylori strains. We find that one<br />
chemoreceptor is sufficient to confer s<strong>of</strong>t-agar migration in our standard Brucella Broth/Fetal<br />
Bovine Serum s<strong>of</strong>t agar. This finding suggests that ligands for each chemoreceptor are found in<br />
this milieu. We also find that mutants lacking some chemoreceptor have an altered stopping<br />
frequency, as noted by Schweinitzer et al (J Bac 2008 190:3244). Mutants lacking all four<br />
chemoreceptors are non-chemotactic and completely smooth swimming, supporting that the<br />
four MA-domain proteins are the only chemoreceptors in this system. Our work thus shows<br />
experimentally that H. pylori possesses four chemoreceptors, and sets the stage for dissecting<br />
what each chemoreceptor senses.<br />
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