1887

Abstract

The LysR-type transcriptional regulator MvfR (PqsR) (ultiple irulence actor egulator) plays a critical role in pathogenicity via the transcriptional regulation of multiple quorum-sensing (QS)-regulated virulence factors. LasR activates full transcription, and MvfR subsequently activates expression. This study identifies and characterizes the key -regulatory elements through which and transcription is regulated in the highly virulent strain PA14. Deletion and site-directed mutagenesis indicate that: (1) LasR activates transcription by binding to a / box, CTAACAAAAGACATAG, centred at −513 bp upstream of the MvfR translational start site; and (2) RhlR represses transcription by binding to a / box, CTGTGAGATTTGGGAG, centred at −311 bp upstream of the transcriptional initiation site. Furthermore, it is shown that MvfR activates transcription by binding to a box, TTCGGACTCCGAA, centred at −45 bp relative to the transcriptional initiation site, demonstrating that this box has a critical role in the physical interaction between the MvfR protein and the promoter. These results provide new insights into the regulatory relationships between LasR and , and between MvfR/RhlR and the operon, and elucidate further the complex regulation of the QS circuitry.

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2006-06-01
2020-03-29
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References

  1. Cao H, Krishnan G, Goumnerov B, Tsongalis J, Tompkins R, Rahme L. G. 2001; A quorum sensing-associated virulence gene of Pseudomonas aeruginosa encodes a LysR-like transcription regulator with a unique self-regulatory mechanism. Proc Natl Acad Sci U S A98:14613–14618[CrossRef]
    [Google Scholar]
  2. Déziel E, Lépine F, Milot S, He J, Mindrinos M. N, Tompkins R. G, Rahme L. G. 2004; Analysis of Pseudomonas aeruginosa 4-hydroxy-2- alkylquinolines (HAQs) reveals a role for 4-hydroxy-2- heptylquinoline in cell-to-cell communication. Proc Natl Acad Sci U S A101:1339–1344[CrossRef]
    [Google Scholar]
  3. Déziel E, Gopalan S, Tampakaki A. P, Padfield K. E, Saucier M, Xiao G, Rahme L. G, Lépine F. 2005; The contribution of MvfR to Pseudomonas aeruginosa pathogenesis and quorum sensing circuitry regulation: multiple quorum sensing-regulated genes are modulated without affecting lasRI , rhlRI or the production of N -acyl-l-homoserine lactones. Mol Microbiol55:998–1014
    [Google Scholar]
  4. Diggle S. P, Winzer K, Chhabra S. R, Worrall K. E, Camara M, Williams P. 2003; The Pseudomonas aeruginosa quinolone signal molecule overcomes the cell density-dependency of the quorum sensing hierarchy, regulates rhl -dependent genes at the onset of stationary phase and can be produced in the absence of LasR. Mol Microbiol50:29–43[CrossRef]
    [Google Scholar]
  5. Farinha M. A, Kropinski A. M. 1990; Construction of broad-host-range plasmid vectors for easy visible selection and analysis of promoters. J Bacteriol172:3496–3499
    [Google Scholar]
  6. Fuqua C, Parsek M. R, Greenberg E. P. 2001; Regulation of gene expression by cell-to-cell communication: acyl-homoserine lactone quorum sensing. Annu Rev Genet35:439–468[CrossRef]
    [Google Scholar]
  7. Gallagher L. A, Manoil C. 2001; Pseudomonas aeruginosa PAO1 kills Caenorhabditis elegans by cyanide poisoning. J Bacteriol183:6207–6214[CrossRef]
    [Google Scholar]
  8. Gallagher L. A, McKnight S. L, Kuznetsova M. S, Pesci E. C, Manoil C. 2002; Functions required for extracellular quinolone signaling by Pseudomonas aeruginosa . J Bacteriol184:6472–6480[CrossRef]
    [Google Scholar]
  9. He J, Baldini R. L, Deziel E.7 other authors 2004; The broad host range pathogen Pseudomonas aeruginosa strain PA14 carries two pathogenicity islands harboring plant and animal virulence genes. Proc Natl Acad Sci U S A101:2530–2535[CrossRef]
    [Google Scholar]
  10. Hentzer M, Wu H, Andersen J. B.15 other authors 2003; Attenuation of Pseudomonas aeruginosa virulence by quorum sensing inhibitors. EMBO J22:3803–3815[CrossRef]
    [Google Scholar]
  11. Juhas M, Wiehlmann L, Huber B.8 other authors 2004; Global regulation of quorum sensing and virulence by VqsR in Pseudomonas aeruginosa . Microbiology150:831–841[CrossRef]
    [Google Scholar]
  12. Lau G. W, Goumnerov B. C, Walendziewicz C. L, Hewitson J, Xiao W, Mahajan-Miklos S, Tompkins R. G, Perkins L. A, Rahme L. G. 2003; The Drosophila melanogaster toll pathway participates in resistance to infection by the gram-negative human pathogen Pseudomonas aeruginosa . Infect Immun71:4059–4066[CrossRef]
    [Google Scholar]
  13. Lépine F, Milot S, He J, Rahme L. G, Déziel E. 2004; Electrospray/mass spectrometric identification and analysis of 4-hydroxy-2-alkylquinolines (HAQs) produced by Pseudomonas aeruginosa . J Am Soc Mass Spectrom15:862–869[CrossRef]
    [Google Scholar]
  14. Lyczak J. B, Cannon C. L, Pier G. B. 2000; Establishment of Pseudomonas aeruginosa infection: lessons from a versatile opportunist. Microbes Infect2:1051–1060[CrossRef]
    [Google Scholar]
  15. Mahajan-Miklos S, Tan M.-W, Rahme L. G, Ausubel F. M. 1999; Molecular mechanisms of bacterial virulence elucidated using a Pseudomonas aeruginosaCaenorhabditis elegans pathogenesis model. Cell96:47–56[CrossRef]
    [Google Scholar]
  16. McGrath S, Wade D. S, Pesci E. C. 2004; Dueling quorum sensing systems in Pseudomonas aeruginosa control the production of the Pseudomonas quinolone signal (PQS). FEMS Microbiol Lett230:27–34[CrossRef]
    [Google Scholar]
  17. McKnight S. L, Iglewski B. H, Pesci E. C. 2000; The Pseudomonas quinolone signal regulates rhl quorum sensing in Pseudomonas aeruginosa . J Bacteriol182:2702–2708[CrossRef]
    [Google Scholar]
  18. Miller J. H. 1972; Assay of β -galactosidase. In Experiments in Molecular Genetics pp 352–355 Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
    [Google Scholar]
  19. Pesci E. C, Iglewski B. 1999; Quorum sensing in Pseudomonas aeruginosa. In Cell-Cell Signaling in Bacteria pp 147–155 Edited by Dunny G. M., Winans S. C.. Washington, DC: American Society for Microbiology;
    [Google Scholar]
  20. Pesci E. C, Milbank J. B. J, Pearson J. P, McKnight S, Kende A. S, Greenberg E. P, Iglewski B. H. 1999; Quinolone signaling in the cell-to-cell communication system of Pseudomonas aeruginosa . Proc Natl Acad Sci U S A96:11229–11234[CrossRef]
    [Google Scholar]
  21. Rahme L. G, Stevens E. J, Wolfort S. F, Shao J, Tompkins R. G, Ausubel F. M. 1995; Common virulence factors for bacterial pathogenicity in plants and animals. Science268:1899–1902[CrossRef]
    [Google Scholar]
  22. Rahme L. G, Tan M.-W, Le L, Wong S. M, Tompkins R. G, Calderwood S. B, Ausubel F. M. 1997; Use of model plants hosts to identify Pseudomonas aeruginosa virulence factors. Proc Natl Acad Sci U S A94:13245–13250[CrossRef]
    [Google Scholar]
  23. Rumbaugh K. P, Griswold J. A, Hamood A. N. 2000; The role of quorum sensing in the in vivo virulence of Pseudomonas aeruginosa . Microbes Infect2:1721–1731[CrossRef]
    [Google Scholar]
  24. Schell M. A. 1993; Molecular biology of the LysR family of transcriptional regulators. Annu Rev Microbiol47:597–626[CrossRef]
    [Google Scholar]
  25. Schuster M, Lostroh C. P, Ogi T, Greenberg E. P. 2003; Identification, timing, and signal specificity of Pseudomonas aeruginosa quorum-controlled genes: a transcriptome analysis. J Bacteriol185:2066–2079[CrossRef]
    [Google Scholar]
  26. Schuster M, Urbanowski M. L, Greenberg E. P. 2004; Promoter specificity in Pseudomonas aeruginosa quorum sensing revealed by DNA binding of purified LasR. Proc Natl Acad Sci U S A101:15833–15839[CrossRef]
    [Google Scholar]
  27. Smith R. S, Iglewski B. 2003; Pseudomonas aeruginosa quorum-sensing systems and virulence. Curr Opin Microbiol6:56–60[CrossRef]
    [Google Scholar]
  28. Wade D. S, Calfee M. W, Rocha E. R, Ling E. A, Engstrom E, Coleman J. P, Pesci E. C. 2005; Regulation of Pseudomonas quinolone signal synthesis in Pseudomonas aeruginosa . J Bacteriol187:4372–4380[CrossRef]
    [Google Scholar]
  29. Whiteley M, Greenberg E. P. 2001; Promoter specificity elements in Pseudomonas aeruginosa quorum-sensing-controlled genes. J Bacteriol183:5529–5534[CrossRef]
    [Google Scholar]
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