title: Increased plasmid copy number is essential for Yersinia T3SS function and virulence.
abstract: Pathogenic bacteria have evolved numerous virulence mechanisms that are essential for establishing infections. The enterobacterium Yersinia uses a type III secretion system (T3SS) encoded by a 70-kilobase, low-copy, IncFII-class virulence plasmid. We report a novel virulence strategy in Y. pseudotuberculosis in which this pathogen up-regulates the plasmid copy number during infection. We found that an increased dose of plasmid-encoded genes is indispensable for virulence and substantially elevates the expression and function of the T3SS. Remarkably, we observed direct, tight coupling between plasmid replication and T3SS function. This regulatory pathway provides a framework for further exploration of the environmental sensing mechanisms of pathogenic bacteria.
authors.affiliation: Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden. Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden.
authors.forename: He
authors.initials: H
authors.lastname: Wang
authors.affiliation: Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden. Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden.
authors.forename: Kemal
authors.initials: K
authors.lastname: Avican
authors.affiliation: Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Fahlgren
authors.affiliation: Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden. Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden.
authors.forename: Saskia F
authors.initials: SF
authors.lastname: Erttmann
authors.affiliation: Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors.forename: Aaron M
authors.initials: AM
authors.lastname: Nuss
authors.affiliation: Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Dersch
authors.affiliation: Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden. Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Fallman
authors.affiliation: Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden. tomas.edgren@umu.se hans.wolf-watz@umu.se.
authors.forename: Tomas
authors.initials: T
authors.lastname: Edgren
authors.affiliation: Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden. Laboratory for Molecular Infection Medicine Sweden (MIMS), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden. tomas.edgren@umu.se hans.wolf-watz@umu.se.
authors.forename: Hans
authors.initials: H
authors.lastname: Wolf-Watz
mesh_terms: D000818:Animals; D018628:Gene Dosage; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D051379:Mice; D010957:Plasmids / Q000235:genetics*; D000069296:Type III Secretion Systems / Q000235:genetics*; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics*; D015011:Yersinia pseudotuberculosis / Q000235:genetics / Q000472:pathogenicity*; D015012:Yersinia pseudotuberculosis Infections / Q000382:microbiology*
chemical_list: D000069296:Type III Secretion Systems; D037521:Virulence Factors