title: Correlation of probiotic Lactobacillus salivarius growth phase with its cell wall-associated proteome.
abstract: Lactobacillus salivarius subsp. salivarius UCC118 is a probiotic bacterium that was originally isolated from human intestinal tissues and was subsequently shown in a pilot study to alleviate symptoms associated with mild-moderate Crohn's disease. Strain UCC118 can adhere to animal and human intestinal tissue, and to both healthy and inflamed ulcerative colitis mucosa, irrespective of location in the gut. In this study, an enzymatic technique has been combined with proteomic analysis to correlate bacterial growth phase with the presence of factors present in the cell wall of the bacterium. Using PAGE electrophoresis, it was determined that progression from lag to log to stationary growth phases in vitro correlated with increasing prominence of an 84kD protein associated with in vitro adherence ability. Isolated proteins from the 84kD band region were further separated by two-dimensional electrophoresis, resolving this band into 20 individual protein spots at differing isoelectric points. The protein moieties were excised, trypsin digested and subjected to tandem mass spectrometry. The observed proteins are analogous to those reported to be associated with the Listeria monocytogenes cell-wall proteome, and include DnaK, Ef-Ts and pyruvate kinase. These data suggest that at least some of the beneficial attributes of probiotic lactobacilli, and in particular this strain, may be due to nonpathogenic mimicry of pathogens and potentially be mediated through a form of attenuated virulence.
authors.affiliation: Department of Medicine, Cork Cancer Research Centre and Alimentary Pharmabiotic Centre at the National University of Ireland, Cork, Ireland.
authors.forename: Peter
authors.initials: P
authors.lastname: Kelly
authors.forename: Patricia B
authors.initials: PB
authors.lastname: Maguire
authors.forename: Mary
authors.initials: M
authors.lastname: Bennett
authors.forename: Desmond J
authors.initials: DJ
authors.lastname: Fitzgerald
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Edwards
authors.forename: Bernd
authors.initials: B
authors.lastname: Thiede
authors.forename: Achim
authors.initials: A
authors.lastname: Treumann
authors.forename: J Kevin
authors.initials: JK
authors.lastname: Collins
authors.forename: Gerald C
authors.initials: GC
authors.lastname: O'Sullivan
authors.forename: Fergus
authors.initials: F
authors.lastname: Shanahan
authors.forename: Colum
authors.initials: C
authors.lastname: Dunne
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007778:Lactobacillus / Q000254:growth & development*; D013058:Mass Spectrometry / Q000379:methods; D008969:Molecular Sequence Data; D019936:Probiotics; D020543:Proteome
chemical_list: D001426:Bacterial Proteins; D020543:Proteome