title: Enhanced adhesion of Campylobacter jejuni to abiotic surfaces is mediated by membrane proteins in oxygen-enriched conditions.
abstract: Campylobacter jejuni is responsible for the major foodborne bacterial enteritis in humans. In contradiction with its fastidious growth requirements, this microaerobic pathogen can survive in aerobic food environments, suggesting that it must employ a variety of protection mechanisms to resist oxidative stress. For the first time, C. jejuni 81-176 inner and outer membrane subproteomes were analyzed separately using two-dimensional protein electrophoresis (2-DE) of oxygen-acclimated cells and microaerobically grown cells. LC-MS/MS analyses successfully identified 42 and 25 spots which exhibited a significantly altered abundance in the IMP-enriched fraction and in the OMP-enriched fraction, respectively, in response to oxidative conditions. These spots corresponded to 38 membrane proteins that could be grouped into different functional classes: (i) transporters, (ii) chaperones, (iii) fatty acid metabolism, (iv) adhesion/virulence and (v) other metabolisms. Some of these proteins were up-regulated at the transcriptional level in oxygen-acclimated cells as confirmed by qRT-PCR. Downstream analyses revealed that adhesion of C. jejuni to inert surfaces and swarming motility were enhanced in oxygen-acclimated cells or paraquat-stressed cells, which could be explained by the higher abundance of membrane proteins involved in adhesion and biofilm formation. The virulence factor CadF, over-expressed in the outer membrane of oxygen-acclimated cells, contributes to the complex process of C. jejuni adhesion to inert surfaces as revealed by a reduction in the capability of C. jejuni 81-176 ΔCadF cells compared to the isogenic strain.Taken together, these data demonstrate that oxygen-enriched conditions promote the over-expression of membrane proteins involved in both the biofilm initiation and virulence of C. jejuni.
authors.affiliation: INRA UMR1014 SECALIM, Nantes, France.
authors.forename: Sheiam
authors.initials: S
authors.lastname: Sulaeman
authors.forename: Mathieu
authors.initials: M
authors.lastname: Hernould
authors.forename: Annick
authors.initials: A
authors.lastname: Schaumann
authors.forename: Laurent
authors.initials: L
authors.lastname: Coquet
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Bolla
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Dé
authors.forename: Odile
authors.initials: O
authors.lastname: Tresse
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D001422:Bacterial Adhesion / Q000187:drug effects / Q000502:physiology*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development; D016123:Campylobacter jejuni / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D005227:Fatty Acids / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism; D018384:Oxidative Stress; D010100:Oxygen / Q000494:pharmacology*; D010269:Paraquat / Q000494:pharmacology; D020543:Proteome / Q000235:genetics / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D001425:Bacterial Outer Membrane Proteins; C107872:CadF protein, Campylobacter jejuni; D002352:Carrier Proteins; D005227:Fatty Acids; D018832:Molecular Chaperones; D020543:Proteome; D010269:Paraquat; D010100:Oxygen