Growth rates and Metabolic Traits Differentiate Campylobacter jejuni Strains by Diarrheal Manifestation

IntroductionCampylobacter jejuni is the leading cause of bacterial gastroenteritis worldwide. Infections with C. jejuni can result in two different diarrheal manifestations in humans: watery diarrhea or bloody/inflammatory diarrhea. Hypothesis/Gap StatementCurrently, little is known about C. jejuni and/or host factors associated with elicitation of these two distinct diarrheal manifestations. We hypothesize that these factors may include growth and metabolic trait differences between C. jejuni strains associated with watery diarrhea and bloody/inflammatory diarrhea. AimUsing C. jejuni strains with a defined diarrheal manifestation in the neonatal piglet model, we aimed to assess differences in temperature dependent growth rates, motility, biofilm production, and carbon utilization between diarrheal manifestation groups. MethodologyStrains were initially assessed for 192 different carbon sources using phenotypic microarrays followed by specific carbon utilization, growth, motility, and biofilm assays at 37{degrees}C and/or 42{degrees}C. ResultsWe found that at 37{degrees}C, watery diarrhea associated C. jejuni strains grew significantly faster compared to bloody/inflammatory diarrhea associated C. jejuni strains. However, there was no significant growth difference at 42{degrees}C between the groups, due to bloody/inflammatory diarrhea associated strains growing faster at 42{degrees}C compared to 37{degrees}C. Additionally at 37{degrees}C, we found that L-fucose utilization was significantly higher among watery diarrhea associated strains, while L-glutamine utilization was significantly higher among bloody/inflammatory diarrhea associated strains. ConclusionThe results indicate there are distinct metabolic adaptations between watery and/or bloody/inflammatory diarrhea associated C. jejuni strains particularly at 37{degrees}C, which may be one of the factors associated with differing diarrheal manifestations.