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A leading cause of bacterial gastroenteritis, <i>Campylobacter jejuni</i> is also associated with broad sequelae, including extragastrointestinal conditions such as reactive arthritis and Guillain-Barré Syndrome (GBS). CbrR is a <i>C. jejuni</i> response regulator that is annotated as a diguanylate cyclase (DGC), an enzyme that catalyzes the synthesis of c-di-GMP, a universal bacterial second messenger, from GTP. In <i>C. jejuni</i> DRH212, we constructed an unmarked deletion mutant, <i>cbrR⁻</i>, and complemented mutant, <i>cbrR⁺</i>. Motility assays indicated a hyper-motile phenotype associated with <i>cbrR⁻</i>, whereas motility was deficient in <i>cbrR⁺</i>. The overexpression of CbrR in <i>cbrR</i>⁺ was accompanied by a reduction in expression of FlaA, the major flagellin. Biofilm assays and scanning electron microscopy demonstrated similarities between DRH212 and <i>cbrR⁻</i>; however, <i>cbrR⁺</i> was unable to form significant biofilms. Transmission electron microscopy showed similar cell morphology between the three strains; however, <i>cbrR⁺</i> cells lacked flagella. Differential radial capillary action of ligand assays (DRaCALA) showed that CbrR binds GTP and c-di-GMP. Liquid chromatography tandem mass spectrometry detected low levels of c-di-GMP in <i>C. jejuni</i> and in <i>E. coli</i> expressing CbrR. CbrR is therefore a negative regulator of FlaA expression and motility, a critical virulence factor in <i>C. jejuni</i> pathogenesis.