title: Modulation of virulence factor expression by pathogen target cell contact.
abstract: Upon contact with the eukaryotic cell, Yersinia pseudotuberculosis increased the rate of transcription of virulence genes (yop), as determined by in situ monitoring of light emission from individual bacteria expressing luciferase under the control of the yopE promoter. The microbe-host interaction triggered export of LcrQ, a negative regulator of Yop expression, via the Yop-type III secretion system. The intracellular concentration of LcrQ was thereby lowered, resulting in increased expression of Yops. These results suggest a key role for the type III secretion system of pathogenic bacteria to coordinate secretion with expression of virulence factors after physical contact with the target cell.
authors.affiliation: Department of Cell and Molecular Biology, University of Umeâ, S-901 87 Umeâ, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Pettersson
authors.forename: R
authors.initials: R
authors.lastname: Nordfelth
authors.forename: E
authors.initials: E
authors.lastname: Dubinina
authors.forename: T
authors.initials: T
authors.lastname: Bergman
authors.forename: M
authors.initials: M
authors.lastname: Gustafsson
authors.forename: K E
authors.initials: KE
authors.lastname: Magnusson
authors.forename: H
authors.initials: H
authors.lastname: Wolf-Watz
mesh_terms: D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D003470:Culture Media; D003600:Cytosol / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D006367:HeLa Cells; D006801:Humans; D009154:Mutation; D015854:Up-Regulation; D014774:Virulence / Q000235:genetics*; D015011:Yersinia pseudotuberculosis / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D003470:Culture Media; C063239:yopE protein, Yersinia; C074427:lcrQ protein, Yersinia pseudotuberculosis; D002118:Calcium