title: An environmentally regulated pilus-like appendage involved in Campylobacter pathogenesis.
abstract: Examination of strains of Campylobacter jejuni, Campylobacter coli, and Campylobacter fetus by electron microscopy revealed that they produced peritrichous pilus-like appendages when the bacteria were grown in the presence of bile salts. Various bile-salt supplements were used and it was found that deoxycholate and chenodeoxycholic acid caused a significant enhancement of pilus production and resulted in a highly aggregative phenotype. Morphologically, the pili were between 4 and 7 nm in width and were greater than 1 micron in length. A gene, termed pspA, which encodes a predicted protein resembling protease IV of Escherichia coli, was identified in C. jejuni strain 81-176. A site-specific insertional mutation within this gene resulted in the loss of pilus synthesis as determined by electron microscopy. Insertions upstream and downstream of the gene had no effect on pilus production. The non-piliated mutant of strain 81-176 showed no reduction in adherence to or invasion of INT 407 cells in vitro. However, this mutant, while still possessing the ability to colonize ferrets, caused significantly reduced disease symptoms in this animal model.
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, British Columbia, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Dolg
authors.forename: R
authors.initials: R
authors.lastname: Yao
authors.forename: D H
authors.initials: DH
authors.lastname: Burr
authors.forename: P
authors.initials: P
authors.lastname: Guerry
authors.forename: T J
authors.initials: TJ
authors.lastname: Trust
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics; D001647:Bile Acids and Salts / Q000494:pharmacology; D002167:Campylobacter / Q000472:pathogenicity* / Q000648:ultrastructure; D002876:Chromosomes, Bacterial / Q000737:chemistry; D003001:Cloning, Molecular; D015342:DNA Probes / Q000378:metabolism; D004195:Disease Models, Animal; D029968:Escherichia coli Proteins; D005260:Female; D005289:Ferrets; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial / Q000235:genetics* / Q000648:ultrastructure; D006360:Heat-Shock Proteins / Q000737:chemistry; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames; D010447:Peptide Hydrolases / Q000737:chemistry; D016415:Sequence Alignment; D012697:Serine Endopeptidases
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D001647:Bile Acids and Salts; D015342:DNA Probes; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; C051592:pneumococcal surface protein A; C070742:sohB protein, E coli; D036781:Fimbriae Proteins; D010447:Peptide Hydrolases; D012697:Serine Endopeptidases; C030732:protease IV