title: Evidence for involvement of at least six proteins in adaptation of Lactobacillus sakei to cold temperatures and addition of NaCl.
abstract: Lactobacillus sakei is a lactic acid bacterium widely represented in the natural flora of fresh meat. The aim of this study was to analyze the differences in protein expression during environmental changes encountered during technological processes in which L. sakei is involved in order to gain insight into the ability of this species to grow and survive in such environments. Using two-dimensional electrophoresis, we observed significant variation of a set of 21 proteins in cells grown at 4 degrees C or in the presence of 4% NaCl. Six proteins could be identified by determination of their N-terminal sequences, and the corresponding gene clusters were studied. Two proteins belong to carbon metabolic pathways, and four can be clustered as general stress proteins. A phenotype was observed at low temperature for five of the six mutants constructed for these genes. The survival of four mutants during stationary phase at 4 degrees C was affected, and surprisingly, one mutant showed enhanced survival during stationary phase at low temperatures.
authors.affiliation: Unité Flore Lactique et Environnement Carné, Institut National de la Recherche Agronomique, Domaine de Vilvert, Jouy en Josas, France.
authors.forename: Anika
authors.initials: A
authors.lastname: Marceau
authors.forename: Monique
authors.initials: M
authors.lastname: Zagorec
authors.forename: Stéphane
authors.initials: S
authors.lastname: Chaillou
authors.forename: Thérèse
authors.initials: T
authors.lastname: Méra
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Champomier-Vergès
mesh_terms: D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003080:Cold Temperature; D015964:Gene Expression Regulation, Bacterial; D018869:Heat-Shock Response; D007778:Lactobacillus / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D012965:Sodium Chloride / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D012965:Sodium Chloride