title: Role of Campylobacter jejuni respiratory oxidases and reductases in host colonization.
abstract: Campylobacter jejuni is the leading cause of human food-borne bacterial gastroenteritis. The C. jejuni genome sequence predicts a branched electron transport chain capable of utilizing multiple electron acceptors. Mutants were constructed by disrupting the coding regions of the respiratory enzymes nitrate reductase (napA::Cm), nitrite reductase (nrfA::Cm), dimethyl sulfoxide, and trimethylamine N-oxide reductase (termed Cj0264::Cm) and the two terminal oxidases, a cyanide-insensitive oxidase (cydA::Cm) and cbb3-type oxidase (ccoN::Cm). Each strain was characterized for the loss of the associated enzymatic function in vitro. The strains were then inoculated into 1-week-old chicks, and the cecal contents were assayed for the presence of C. jejuni 2 weeks postinoculation. cydA::Cm and Cj0264c::Cm strains colonized as well as the wild type; napA::Cm and nrfA::Cm strains colonized at levels significantly lower than the wild type. The ccoN::Cm strain was unable to colonize the chicken; no colonies were recovered at the end of the experiment. While there appears to be a role for anaerobic respiration in host colonization, oxygen is the most important respiratory acceptor for C. jejuni in the chicken cecum.
authors.affiliation: Department of Microbiology, North Carolina State University, Raleigh, North Carolina 27695, USA.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Weingarten
authors.forename: Jesse L
authors.initials: JL
authors.lastname: Grimes
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Olson
mesh_terms: D000818:Animals; D016123:Campylobacter jejuni / Q000201:enzymology* / Q000254:growth & development*; D002432:Cecum / Q000382:microbiology*; D002645:Chickens / Q000382:microbiology*; D015169:Colony Count, Microbial; D017931:DNA Primers / Q000235:genetics; D040461:Gene Components; D013058:Mass Spectrometry; D016296:Mutagenesis; D009566:Nitrates / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D013045:Species Specificity
chemical_list: D017931:DNA Primers; D009566:Nitrates; D010088:Oxidoreductases; D010100:Oxygen