1887

Abstract

Extracellular DNA is one of the major matrix components in biofilms. It functions as an intercellular connector and plays a role in stabilization of the biofilms. Evidence that DNA release in PAO1 biofilms is controlled by the - and quorum-sensing systems has been previously presented. This paper provides evidence that DNA release in PAO1 biofilms is also under iron regulation. Experiments involving cultivation of in microtitre trays suggested that expression, DNA release and biofilm formation were favoured in media with low iron concentrations (5 μM FeCl), and decreased with increasing iron concentrations. Experiments involving cultivation of in a flow-chamber system suggested that a high level of iron (100 μM FeCl) in the medium suppressed DNA release, structural biofilm development, and the development of subpopulations with increased tolerance toward antimicrobial compounds. Experiments with strains harbouring fluorescent reporters suggested that expression of the operon was induced in particular subpopulations of the biofilm cells under low-iron conditions (1 μM FeCl), but repressed in the biofilm cells under high-iron conditions (100 μM FeCl).

Loading

Article metrics loading...

/content/journal/micro/10.1099/mic.0.2006/004911-0
2007-05-01
2019-11-12
Loading full text...

Full text loading...

/deliver/fulltext/micro/153/5/1318.html?itemId=/content/journal/micro/10.1099/mic.0.2006/004911-0&mimeType=html&fmt=ahah

References

  1. Allesen-Holm, M., Barken, K. B., Yang, L., Klausen, M., Webb, J. S., Kjelleberg, S., Molin, S., Givskov, M. & Tolker-Nielsen, T. ( 2006; ). A characterization of DNA release in Pseudomonas aeruginosa cultures and biofilms. Mol Microbiol 59, 1114–1128.[CrossRef]
    [Google Scholar]
  2. Andersen, J. B., Sternberg, C., Poulsen, L. K., Bjorn, S. P., Givskov, M. & Molin, S. ( 1998; ). New unstable variants of green fluorescent protein for studies of transient gene expression in bacteria. Appl Environ Microbiol 64, 2240–2246.
    [Google Scholar]
  3. Andersen, J. B., Heydorn, A., Hentzer, M., Eberl, L., Geisenberger, O., Christensen, B. B., Molin, S. & Givskov, M. ( 2001; ). gfp-based N-acyl homoserine-lactone sensor systems for detection of bacterial communication. Appl Environ Microbiol 67, 575–585.[CrossRef]
    [Google Scholar]
  4. Baltimore, R. S., Christie, C. D. & Smith, G. J. ( 1989; ). Immunohistopathologic localization of Pseudomonas aeruginosa in lungs from patients with cystic fibrosis. Implications for the pathogenesis of progressive lung deterioration. Am Rev Respir Dis 140, 1650–1661.[CrossRef]
    [Google Scholar]
  5. Banin, E., Vasil, M. L. & Greenberg, E. P. ( 2005; ). Iron and Pseudomonas aeruginosa biofilm formation. Proc Natl Acad Sci U S A 102, 11076–11081.[CrossRef]
    [Google Scholar]
  6. Banin, E., Brady, K. M. & Greenberg, E. P. ( 2006; ). Chelator-induced dispersal and killing of Pseudomonas aeruginosa cells in a biofilm. App Environ Microbial 72, 2064–2069.[CrossRef]
    [Google Scholar]
  7. Bertani, G. ( 1951; ). Studies on lysogenesis. I. The mode of phage liberation by lysogenic Escherichia coli. J Bacteriol 62, 293–300.
    [Google Scholar]
  8. Bjarnsholt, T., Jensen, P. O., Burmolle, M., Hentzer, M., Haagensen, J. A., Hougen, H. P., Calum, H., Madsen, K. G., Moser, C. & other authors ( 2005; ). Pseudomonas aeruginosa tolerance to tobramycin, hydrogen peroxide and polymorphonuclear leukocytes is quorum-sensing dependent. Microbiology 151, 373–383.[CrossRef]
    [Google Scholar]
  9. Bjorn, M. J., Sokol, P. A. & Iglewski, B. H. ( 1979; ). Influence of iron on yields of extracellular products in Pseudomonas aeruginosa cultures. J Bacteriol 138, 193–200.
    [Google Scholar]
  10. Bollinger, N., Hassett, D. J., Iglewski, B. H., Costerton, J. W. & McDermott, T. R. ( 2001; ). Gene expression in Pseudomonas aeruginosa: evidence of iron override effects on quorum sensing and biofilm-specific gene regulation. J Bacteriol 183, 1990–1996.[CrossRef]
    [Google Scholar]
  11. Brint, J. M. & Ohman, D. E. ( 1995; ). Synthesis of multiple exoproducts in Pseudomonas aeruginosa is under the control of RhlR-RhlI, another set of regulators in strain PAO1 with homology to the autoinducer-responsive LuxR-LuxI family. J Bacteriol 177, 7155–7163.
    [Google Scholar]
  12. 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 A 98, 14613–14618.[CrossRef]
    [Google Scholar]
  13. Clark, D. J. & Maaløe, O. ( 1967; ). DNA replication and the division cycle in Escherichia coli. J Mol Biol 23, 99–112.[CrossRef]
    [Google Scholar]
  14. Cornelis, P. & Aendekerk, S. ( 2004; ). A new regulator linking quorum sensing and iron uptake in Pseudomonas aeruginosa. Microbiology 150, 752–756.[CrossRef]
    [Google Scholar]
  15. Costerton, J. W., Stewart, P. S. & Greenberg, E. P. ( 1999; ). Bacterial biofilms: a common cause of persistent infections. Science 284, 1318–1322.[CrossRef]
    [Google Scholar]
  16. D'Argenio, D. A., Calfee, M. W., Rainey, P. B. & Pesci, E. C. ( 2002; ). Autolysis and autoaggregation in Pseudomonas aeruginosa colony morphology mutants. J Bacteriol 184, 6481–6489.[CrossRef]
    [Google Scholar]
  17. Davey, M. E. & O'Toole, G. A. ( 2000; ). Microbial biofilms: from ecology to molecular genetics. Microbiol Mol Biol Rev 64, 847–867.[CrossRef]
    [Google Scholar]
  18. Davies, D. G., Parsek, M. R., Pearson, J. P., Iglewski, B. H., Costerton, J. W. & Greenberg, E. P. ( 1998; ). The involvement of cell-to-cell signals in the development of a bacterial biofilm. Science 280, 295–298.[CrossRef]
    [Google Scholar]
  19. 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 Bacteriol 184, 6472–6480.[CrossRef]
    [Google Scholar]
  20. Haagensen, J. A., Klausen, M., Ernst, R. K., Miller, S. I., Folkesson, A., Tolker-Nielsen, T. & Molin, S. ( 2007; ). Differentiation and distribution of colistin/SDS tolerant cells in Pseudomonas aeruginosa biofilms. J Bacteriol 189, 28–37.[CrossRef]
    [Google Scholar]
  21. Haas, B., Kraut, J., Marks, J., Zanker, S. C. & Castignetti, D. ( 1991; ). Siderophore presence in sputa of cystic fibrosis patients. Infect Immun 59, 3997–4000.
    [Google Scholar]
  22. Hassett, D. J., Charniga, L., Bean, K., Ohman, D. E. & Cohen, M. S. ( 1992; ). Response of Pseudomonas aeruginosa to pyocyanin: mechanisms of resistance, antioxidant defenses, and demonstration of a manganese-cofactored superoxide dismutase. Infect Immun 60, 328–336.
    [Google Scholar]
  23. Hassett, D. J., Howell, M. L., Sokol, P. A., Vasil, M. L. & Dean, G. E. ( 1997; ). Fumarase C activity is elevated in response to iron deprivation and in mucoid, alginate-producing Pseudomonas aeruginosa: cloning and characterization of fumC and purification of native fumC. J Bacteriol 179, 1442–1451.
    [Google Scholar]
  24. Hassett, D. J., Ma, J. F., Elkins, J. G., McDermott, T. R., Ochsner, U. A., West, S. E., Huang, C. T., Fredericks, J., Burnett, S. & other authors ( 1999; ). Quorum sensing in Pseudomonas aeruginosa controls expression of catalase and superoxide dismutase genes and mediates biofilm susceptibility to hydrogen peroxide. Mol Microbiol 34, 1082–1093.[CrossRef]
    [Google Scholar]
  25. Hentzer, M., Wu, H., Andersen, J. B., Riedel, K., Rasmussen, T. B., Bagge, N., Kumar, N., Schembri, M. A., Song, Z. & other authors ( 2003; ). Attenuation of Pseudomonas aeruginosa virulence by quorum sensing inhibitors. EMBO J 22, 3803–3815.[CrossRef]
    [Google Scholar]
  26. Heydorn, A., Nielsen, A. T., Hentzer, M., Sternberg, C., Givskov, M., Ersboll, B. K. & Molin, S. ( 2000; ). Quantification of biofilm structures by the novel computer program COMSTAT. Microbiology 146, 2395–2407.
    [Google Scholar]
  27. Høiby, N., Krogh Johansen, H., Moser, C., Song, Z., Ciofu, O. & Kharazmi, A. ( 2001; ). Pseudomonas aeruginosa and the in vitro and in vivo biofilm mode of growth. Microbes Infect 3, 23–35.[CrossRef]
    [Google Scholar]
  28. Johnson, M., Cockayne, A., Williams, P. H. & Morrissey, J. A. ( 2005; ). Iron-responsive regulation of biofilm formation in Staphylococcus aureus involves Fur-dependent and Fur-independent mechanisms. J Bacteriol 187, 8211–8215.[CrossRef]
    [Google Scholar]
  29. Klausen, M., Aaes-Jorgensen, A., Molin, S. & Tolker-Nielsen, T. ( 2003a; ). Involvement of bacterial migration in the development of complex multicellular structures in Pseudomonas aeruginosa biofilms. Mol Microbiol 50, 61–68.[CrossRef]
    [Google Scholar]
  30. Klausen, M., Heydorn, A., Ragas, P., Lambertsen, L., Aaes-Jorgensen, A., Molin, S. & Tolker-Nielsen, T. ( 2003b; ). Biofilm formation by Pseudomonas aeruginosa wild type, flagella and type IV pili mutants. Mol Microbiol 48, 1511–1524.[CrossRef]
    [Google Scholar]
  31. Lam, J., Chan, R., Lam, K. & Costerton, J. W. ( 1980; ). Production of mucoid microcolonies by Pseudomonas aeruginosa within infected lungs in cystic fibrosis. Infect Immun 28, 546–556.
    [Google Scholar]
  32. Latifi, A., Winson, M. K., Foglino, M., Bycroft, B. W., Stewart, G. S., Lazdunski, A. & Williams, P. ( 1995; ). Multiple homologues of LuxR and LuxI control expression of virulence determinants and secondary metabolites through quorum sensing in Pseudomonas aeruginosa PAO1. Mol Microbiol 17, 333–343.[CrossRef]
    [Google Scholar]
  33. Latifi, A., Foglino, M., Tanaka, K., Williams, P. & Lazdunski, A. ( 1996; ). A hierarchical quorum-sensing cascade in Pseudomonas aeruginosa links the transcriptional activators LasR and RhIR (VsmR) to expression of the stationary-phase sigma factor RpoS. Mol Microbiol 21, 1137–1146.[CrossRef]
    [Google Scholar]
  34. Matsukawa, M. & Greenberg, E. P. ( 2004; ). Putative exopolysaccharide synthesis genes influence Pseudomonas aeruginosa biofilm development. J Bacteriol 186, 4449–4456.[CrossRef]
    [Google Scholar]
  35. Miller, J. H. ( 1972; ). Experiments in Molecular Genetics. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory.
  36. Musk, D. J., Banko, D. A. & Hergenrother, P. J. ( 2005; ). Iron salts perturb biofilm formation and disrupt existing biofilms of Pseudomonas aeruginosa. Chem Biol 12, 789–796.[CrossRef]
    [Google Scholar]
  37. Nemoto, K., Hirota, K., Murakami, K., Taniguti, K., Murata, H., Viducic, D. & Miyake, Y. ( 2003; ). Effect of Varidase (streptodornase) on biofilm formed by Pseudomonas aeruginosa. Chemotherapy 49, 121–125.[CrossRef]
    [Google Scholar]
  38. Ochsner, U. A., Wilderman, P. J., Vasil, A. I. & Vasil, M. L. ( 2002; ). GeneChip expression analysis of the iron starvation response in Pseudomonas aeruginosa: identification of novel pyoverdine biosynthesis genes. Mol Microbiol 45, 1277–1287.[CrossRef]
    [Google Scholar]
  39. O'Toole, G. A. & Kolter, R. ( 1998; ). Flagellar and twitching motility are necessary for Pseudomonas aeruginosa biofilm development. Mol Microbiol 30, 295–304.[CrossRef]
    [Google Scholar]
  40. Palmer, K. L., Mashburn, L. M., Singh, P. K. & Whiteley, M. ( 2005; ). Cystic fibrosis sputum supports growth and cues key aspects of Pseudomonas aeruginosa physiology. J Bacteriol 187, 5267–5277.[CrossRef]
    [Google Scholar]
  41. Passador, L., Cook, J. M., Gambello, M. J., Rust, L. & Iglewski, B. H. ( 1993; ). Expression of Pseudomonas aeruginosa virulence genes requires cell-to-cell communication. Science 260, 1127–1130.[CrossRef]
    [Google Scholar]
  42. Pesci, E. C., Milbank, J. B., 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 A 96, 11229–11234.[CrossRef]
    [Google Scholar]
  43. Ratledge, C. & Dover, L. G. ( 2000; ). Iron metabolism in pathogenic bacteria. Annu Rev Microbiol 54, 881–941.[CrossRef]
    [Google Scholar]
  44. Rombel, I. T., McMorran, B. J. & Lamont, I. L. ( 1995; ). Identification of a DNA sequence motif required for expression of iron-regulated genes in pseudomonads. Mol Gen Genet 246, 519–528.[CrossRef]
    [Google Scholar]
  45. Sambrook, J., Fritsch, E. F. & Maniatis, T. ( 1989; ). Molecular Cloning: a Laboratory Manual, 2nd edn, vol. 1. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory.
  46. Sauer, K., Camper, A. K., Ehrlich, G. D., Costerton, J. W. & Davies, D. G. ( 2002; ). Pseudomonas aeruginosa displays multiple phenotypes during development as a biofilm. J Bacteriol 184, 1140–1154.[CrossRef]
    [Google Scholar]
  47. Singh, P. K., Parsek, M. R., Greenberg, E. P. & Welsh, M. J. ( 2002; ). A component of innate immunity prevents bacterial biofilm development. Nature 417, 552–555.[CrossRef]
    [Google Scholar]
  48. Sokol, P. A., Cox, C. D. & Iglewski, B. H. ( 1982; ). Pseudomonas aeruginosa mutants altered in their sensitivity to the effect of iron on toxin A or elastase yields. J Bacteriol 151, 783–787.
    [Google Scholar]
  49. Sriramulu, D. D., Lünsdorf, H., Lam, J. S. & Römling, U. ( 2005; ). Microcolony formation: a novel biofilm model of Pseudomonas aeruginosa for the cystic fibrosis lung. J Med Microbiol 54, 667–676.[CrossRef]
    [Google Scholar]
  50. Sternberg, C. & Tolker-Nielsen, T. ( 2005; ). Growing and analyzing biofilms in flow cells. In Current Protocols in Microbiology, 1B.2.1–1B.2.15. Edited by R. Coico, T. Kowalik, J. Quarles, B. Stevenson & R. Taylor. New York: Wiley.
  51. Sutherland, I. W. ( 2001; ). The biofilm matrix – an immobilized but dynamic microbial environment. Arch Microbiol 9, 222–227.
    [Google Scholar]
  52. Weinberg, E. D. ( 1999; ). Iron loading and disease surveillance. Emerg Infect Dis 5, 346–352.[CrossRef]
    [Google Scholar]
  53. Whitchurch, C. B., Tolker-Nielsen, T., Ragas, P. C. & Mattick, J. S. ( 2002; ). Extracellular DNA required for bacterial biofilm formation. Science 295, 1487.[CrossRef]
    [Google Scholar]
  54. Winson, M. K., Camara, M., Latifi, A., Foglino, M., Chhabra, S. R., Daykin, M., Bally, M., Chapon, V., Salmond, G. P. & other authors ( 1995; ). Multiple N-acyl-l-homoserine lactone signal molecules regulate production of virulence determinants and secondary metabolites in Pseudomonas aeruginosa. Proc Natl Acad Sci U S A 92, 9427–9431.[CrossRef]
    [Google Scholar]
  55. Worlitzsch, D., Tarran, R., Ulrich, M., Schwab, U., Cekici, A., Meyer, K. C., Birrer, P., Bellon, G., Berger, J. & other authors ( 2002; ). Effects of reduced mucus oxygen concentration in airway Pseudomonas infections of cystic fibrosis patients. J Clin Invest 109, 317–325.[CrossRef]
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/mic.0.2006/004911-0
Loading
/content/journal/micro/10.1099/mic.0.2006/004911-0
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error