title: Critical role of LuxS in the virulence of Campylobacter jejuni in a guinea pig model of abortion.
abstract: Previous studies on Campylobacter jejuni have demonstrated the role of LuxS in motility, cytolethal distending toxin production, agglutination, and intestinal colonization; however, its direct involvement in virulence has not been reported. In this study, we demonstrate a direct role of luxS in the virulence of C. jejuni in two different animal hosts. The IA3902 strain, a highly virulent sheep abortion strain recently described by our laboratory, along with its isogenic luxS mutant and luxS complement strains, was inoculated by the oral route into both a pregnant guinea pig virulence model and a chicken colonization model. In both cases, the IA3902 luxS mutant demonstrated a complete loss of ability to colonize the intestinal tract. In the pregnant model, the mutant also failed to induce abortion, while the wild-type strain was highly abortifacient. Genetic complementation of the luxS gene fully restored the virulent phenotype in both models. Interestingly, when the organism was inoculated into guinea pigs by the intraperitoneal route, no difference in virulence (abortion induction) was observed between the luxS mutant and the wild-type strain, suggesting that the defect in virulence following oral inoculation is likely associated with a defect in colonization and/or translocation of the organism out of the intestine. These studies provide the first direct evidence that LuxS plays an important role in the virulence of C. jejuni using an in vivo model of natural disease.
authors.affiliation: Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Plummer
authors.forename: Orhan
authors.initials: O
authors.lastname: Sahin
authors.forename: Eric
authors.initials: E
authors.lastname: Burrough
authors.forename: Rachel
authors.initials: R
authors.lastname: Sippy
authors.forename: Kathy
authors.initials: K
authors.lastname: Mou
authors.forename: Jessica
authors.initials: J
authors.lastname: Rabenold
authors.forename: Mike
authors.initials: M
authors.lastname: Yaeger
authors.forename: Qijing
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000031:Abortion, Septic / Q000382:microbiology*; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002169:Campylobacter Infections / Q000382:microbiology* / Q000473:pathology; D016123:Campylobacter jejuni / Q000378:metabolism / Q000472:pathogenicity*; D013437:Carbon-Sulfur Lyases / Q000235:genetics / Q000378:metabolism*; D002645:Chickens; D004195:Disease Models, Animal; D005260:Female; D006168:Guinea Pigs; D007422:Intestines / Q000382:microbiology; D009154:Mutation; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000382:microbiology / Q000473:pathology; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D013437:Carbon-Sulfur Lyases; C117753:LuxS protein, Bacteria