title: CadF expression in Campylobacter jejuni strains incubated under low-temperature water microcosm conditions which induce the viable but non-culturable (VBNC) state.
abstract: Campylobacter jejuni is a major gastrointestinal pathogen that colonizes host mucosa via interactions with extracellular matrix proteins such as fibronectin. The aim of this work was to study in vitro the adhesive properties of C. jejuni ATCC 33291 and C. jejuni 241 strains, in both culturable and viable but non-culturable (VBNC) forms. To this end, the expression of the outer-membrane protein CadF, which mediates C. jejuni binding to fibronectin, was evaluated. VBNC bacteria were obtained after 46-48 days of incubation in freshwater at 4 °C. In both cellular forms, the expression of the cadF gene, assessed at different time points by RT-PCR, was at high levels until the third week of VBNC induction, while the intensity of the signal declined during the last stage of incubation. CadF protein expression by the two C. jejuni strains was analysed using 2-dimensional electrophoresis and mass spectrometry; the results indicated that the protein, although at low levels, is also present in the VBNC state. Adhesion assays with culturable and VBNC cells, evaluated on Caco-2 monolayers, showed that non-culturable bacteria retain their ability to adhere to intestinal cells, though at a reduced rate. Our results demonstrate that the C. jejuni VBNC population maintains an ability to adhere and this may thus have an important role in the pathogenicity of this microorganism.
authors: Division of Toxicology, Hygienic and Environmental Sciences Department of Biomolecular Sciences, University of Urbino Carlo Bo, Via S. Chiara 27, 61029, Urbino, Italy.
authors: Vania
authors: V
authors: Patrone
authors: Raffaella
authors: R
authors: Campana
authors: Luciana
authors: L
authors: Vallorani
authors: Sabrina
authors: S
authors: Dominici
authors: Sara
authors: S
authors: Federici
authors: Lucia
authors: L
authors: Casadei
authors: Anna Maria
authors: AM
authors: Gioacchini
authors: Vilberto
authors: V
authors: Stocchi
authors: Wally
authors: W
authors: Baffone
mesh_terms: D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis*; D018938:Caco-2 Cells; D016123:Campylobacter jejuni / Q000235:genetics* / Q000254:growth & development / Q000528:radiation effects*; D002352:Carrier Proteins / Q000096:biosynthesis*; D003080:Cold Temperature; D015180:Electrophoresis, Gel, Two-Dimensional; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D013058:Mass Spectrometry; D050296:Microbial Viability; D060888:Real-Time Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D001425:Bacterial Outer Membrane Proteins; C107872:CadF protein, Campylobacter jejuni; D002352:Carrier Proteins