title: Inactivation of Francisella tularensis Gene Encoding Putative ABC Transporter Has a Pleiotropic Effect upon Production of Various Glycoconjugates.
abstract: Francisella tularensis, an intracellular pathogen causing the disease tularemia, utilizes surface glycoconjugates such as lipopolysaccharide, capsule, and capsule-like complex for its protection against inhospitable conditions of the environment. Francisella species also possess a functional glycosylation apparatus by which specific proteins are O-glycosidically modified. We here created a mutant with a nonfunctional FTS_1402 gene encoding for a putative glycan flippase and studied the consequences of its disruption. The mutant strain expressed diminished glycosylation similarly to, but to a lesser extent than, that of the oligosaccharyltransferase-deficient ΔpglA mutant. In contrast to ΔpglA, inactivation of FTS_1402 had a pleiotropic effect, leading to alteration in glycosylation and, importantly, to decrease in lipopolysaccharide, capsule, and/or capsule-like complex production, which were reflected by distinct phenotypes in host-pathogen associated properties and virulence potential of the two mutant strains. Disruption of FTS_1402 resulted in enhanced sensitivity to complement-mediated lysis and reduced virulence in mice that was independent of diminished glycosylation. Importantly, the mutant strain induced a protective immune response against systemic challenge with homologous wild-type FSC200 strain. Targeted disruption of genes shared by multiple metabolic pathways may be considered a novel strategy for constructing effective live, attenuated vaccines.
authors.affiliation: Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence , Hradec Kralove 500 01, Czech Republic.
authors.forename: Vera
authors.initials: V
authors.lastname: Dankova
authors.affiliation: Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence , Hradec Kralove 500 01, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Balonova
authors.affiliation: Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence , Hradec Kralove 500 01, Czech Republic.
authors.forename: Marek
authors.initials: M
authors.lastname: Link
authors.affiliation: Department of Phototrophic Microorganisms, Institute of Microbiology, The Academy of Sciences of The Czech Republic , Trebon 379 81, Czech Republic.
authors.forename: Adela
authors.initials: A
authors.lastname: Straskova
authors.affiliation: Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence , Hradec Kralove 500 01, Czech Republic.
authors.forename: Valeria
authors.initials: V
authors.lastname: Sheshko
authors.affiliation: Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence , Hradec Kralove 500 01, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Stulik
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002853:Chromatography, Liquid; D005260:Female; D005604:Francisella tularensis / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D015964:Gene Expression Regulation, Bacterial; D020868:Gene Silencing; D058685:Genetic Pleiotropy; D006001:Glycoconjugates / Q000096:biosynthesis*; D006031:Glycosylation; D006602:Hexosyltransferases / Q000235:genetics / Q000378:metabolism; D054884:Host-Pathogen Interactions; D008070:Lipopolysaccharides / Q000096:biosynthesis; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008807:Mice, Inbred BALB C; D009154:Mutation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053719:Tandem Mass Spectrometry; D014406:Tularemia / Q000382:microbiology; D014774:Virulence / Q000235:genetics
chemical_list: D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D006001:Glycoconjugates; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D006602:Hexosyltransferases; C025620:dolichyl-diphosphooligosaccharide - protein glycotransferase
keywords: ABC transporter; Francisella tularensis; capsule; glycosylation; lipopolysaccharide