title: Comparative proteome analysis of fractions enriched for membrane-associated proteins from Francisella tularensis subsp. tularensis and F. tularensis subsp. holarctica strains.
abstract: The facultative intracellular pathogen Francisella tularensis is the causative agent of the serious infectious disease tularemia. Despite intensive research, the virulence factors and pathogenetic mechanisms remain largely unknown. To identify novel putative virulence factors, we carried out a comparative proteome analysis of fractions enriched for membrane-associated proteins isolated from the highly virulent subspecies tularensis strain SCHU S4 and three representatives of subspecies holarctica of different virulence including the live vaccine strain. We identified six proteins uniquely expressed and four proteins expressed at significantly higher levels by SCHU S4 compared to the ssp. holarctica strains. Four other protein spots represented mass and charge variants and seven spots were charge variants of proteins occurring in the ssp. holarctica strains. The genes encoding proteins of particular interest were examined by sequencing in order to confirm and explain the findings of the proteome analysis. Our studies suggest that the subspecies tularensis-specific proteins represent novel potential virulence factors.
authors.affiliation: Institute of Molecular Pathology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic, Veterinary Research Institute, Brno, Czech Republic. pavkova@pmfhk.cz
authors.forename: Ivona
authors.initials: I
authors.lastname: Pavkova
authors.forename: Marketa
authors.initials: M
authors.lastname: Reichelova
authors.forename: Pär
authors.initials: P
authors.lastname: Larsson
authors.forename: Martin
authors.initials: M
authors.lastname: Hubalek
authors.forename: Jana
authors.initials: J
authors.lastname: Vackova
authors.forename: Ake
authors.initials: A
authors.lastname: Forsberg
authors.forename: Jiri
authors.initials: J
authors.lastname: Stulik
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D004396:Coloring Agents; D019295:Computational Biology; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D004798:Enzymes / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D005603:Francisella / Q000737:chemistry* / Q000235:genetics / Q000472:pathogenicity; D005604:Francisella tularensis / Q000737:chemistry* / Q000235:genetics / Q000472:pathogenicity; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D040901:Proteomics / Q000379:methods; D012834:Silver; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D004396:Coloring Agents; D004798:Enzymes; D008565:Membrane Proteins; D010446:Peptide Fragments; D012834:Silver