title: Global regulation of quorum sensing and virulence by VqsR in Pseudomonas aeruginosa.
abstract: Pathogenesis of Pseudomonas aeruginosa is controlled to a major extent by the two quorum-sensing systems las and rhl. The previously uncharacterized gene PA2591 was identified as a major virulence regulator, vqsR, in the quorum-sensing hierarchy. vqsR is a member of the LuxR family and possesses a las box in its upstream region. Transposon inactivation of vqsR abrogated the production of N-acylhomoserine lactones and the secretion of exoproducts and diminished bacterial virulence for Caenorhabditis elegans. Cytotoxicity towards macrophages was not affected. vqsR mRNA was expressed more strongly in the presence of human serum and oxidative stress than under standard growth conditions. High-density oligonucleotide microarrays were used to compare the global expression profile of a wild-type strain and a vqsR mutant. One-hundred-and-fifty-one and 113 genes were significantly differentially expressed in the presence of H(2)O(2) and human serum, respectively. The disruption of vqsR repressed the expression of genes that are known to be promoted by quorum sensing and activated the expression of genes that are known to be repressed by quorum sensing. Moreover, the vqsR mutant harboured less mRNA transcript for the production of siderophores and membrane-bound elements of antibiotic resistance. The protein encoded by PA2591 regulates several traits of pathogenicity; hence, the name vqsR ('virulence and quorum-sensing regulator') was assigned to PA2591.
authors.affiliation: Clinical Research Group, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Mario
authors.initials: M
authors.lastname: Juhas
authors.affiliation: Clinical Research Group, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Wiehlmann
authors.affiliation: Department of Microbiology, Technical University Munich, Am Hochanger 4, D-85350 Freising, Germany.
authors.forename: Birgit
authors.initials: B
authors.lastname: Huber
authors.affiliation: Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Doris
authors.initials: D
authors.lastname: Jordan
authors.affiliation: German Research Centre for Biotechnology, Mascheroder Weg 1, 38124 Braunschweig, Germany.
authors.forename: Joerg
authors.initials: J
authors.lastname: Lauber
authors.affiliation: Clinical Research Group, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Prabhakar
authors.initials: P
authors.lastname: Salunkhe
authors.affiliation: Clinical Research Group, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Anna Silke
authors.initials: AS
authors.lastname: Limpert
authors.affiliation: Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.|Clinical Research Group, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Franz
authors.initials: F
authors.lastname: von Götz
authors.affiliation: Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Ivo
authors.initials: I
authors.lastname: Steinmetz
authors.affiliation: Department of Microbiology, Institute of Plant Biology, University Zürich, CH-8008 Zürich, Switzerland.
authors.forename: Leo
authors.initials: L
authors.lastname: Eberl
authors.affiliation: Clinical Research Group, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Tümmler
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives / Q000378:metabolism; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D017173:Caenorhabditis elegans / Q000382:microbiology*; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D009000:Monocytes; D020411:Oligonucleotide Array Sequence Analysis; D020543:Proteome; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000472:pathogenicity*; D015398:Signal Transduction; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D020543:Proteome; D015534:Trans-Activators; C088386:homoserine lactone; D015107:4-Butyrolactone