title: Changes in Escherichia coli outer membrane subproteome under environmental conditions inducing the viable but nonculturable state.
abstract: Changes in the outer membrane subproteome of Escherichia coli along the transition to the viable but nonculturable state (VBNC) were studied. The VBNC state was triggered by exposure of E. coli cells to adverse conditions such as aquatic systems, starvation, suboptimal temperature, visible light irradiation and seawater. The subproteome, obtained according to Molloy et al., was analysed at the beginning of exposure (inoculum, phase 1), after a variable exposure time (95% of population culturable, phase 2) and when populations were mainly in the VBNC state (95% of cells VBNC, phase 3). Proteome changes were dependent on adverse conditions inducing the transition and were detected mainly in phase 2. The permanence of E. coli cells in seawater under illumination conditions entailed a dramatic rearrangement of the outer membrane subproteome involving 106 new spots, some of which could be identified by peptide fingerprinting. However, proteins exclusive to the VBNC state were not detected.
authors.affiliation: Departamento de Inmunología, Microbiología y Parasitología, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Bilbao, Spain.
authors.forename: Alicia
authors.initials: A
authors.lastname: Muela
authors.forename: Carolina
authors.initials: C
authors.lastname: Seco
authors.forename: Emilio
authors.initials: E
authors.lastname: Camafeita
authors.forename: Inés
authors.initials: I
authors.lastname: Arana
authors.forename: Maite
authors.initials: M
authors.lastname: Orruño
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: López
authors.forename: Isabel
authors.initials: I
authors.lastname: Barcina
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D015169:Colony Count, Microbial; D003470:Culture Media; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D018869:Heat-Shock Response; D008027:Light; D050296:Microbial Viability; D020543:Proteome; D040901:Proteomics; D012623:Seawater
chemical_list: D001425:Bacterial Outer Membrane Proteins; D003470:Culture Media; D029968:Escherichia coli Proteins; D020543:Proteome