This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Russo, D. M.
Right arrow Articles by Zorreguieta, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Russo, D. M.
Right arrow Articles by Zorreguieta, A.

 Previous Article  |  Next Article 

Journal of Bacteriology, June 2006, p. 4474-4486, Vol. 188, No. 12
0021-9193/06/$08.00+0     doi:10.1128/JB.00246-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Proteins Exported via the PrsD-PrsE Type I Secretion System and the Acidic Exopolysaccharide Are Involved in Biofilm Formation by Rhizobium leguminosarum

Daniela M. Russo,1 Alan Williams,2 Anne Edwards,2 Diana M. Posadas,1 Christine Finnie,2,{dagger} Marcelo Dankert,1 J. Allan Downie,2 and Angeles Zorreguieta1,2*

Fundación Instituto Leloir, CONICET, and Inst. de Investigaciones Bioquímicas, FCEyN, University of Buenos Aires, Patricias Argentinas 435, (C1405BWE) Buenos Aires, Argentina,1 John Innes Centre, Norwich Research Park, Colney, Norwich, NR4 7 UH, United Kingdom2

Received 16 February 2006/ Accepted 27 March 2006

The type I protein secretion system of Rhizobium leguminosarum bv. viciae encoded by the prsD and prsE genes is responsible for secretion of the exopolysaccharide (EPS)-glycanases PlyA and PlyB. The formation of a ring of biofilm on the surface of the glass in shaken cultures by both the prsD and prsE secretion mutants was greatly affected. Confocal laser scanning microscopy analysis of green-fluorescent-protein-labeled bacteria showed that during growth in minimal medium, R. leguminosarum wild type developed microcolonies, which progress to a characteristic three-dimensional biofilm structure. However, the prsD and prsE secretion mutants were able to form only an immature biofilm structure. A mutant disrupted in the EPS-glycanase plyB gene showed altered timing of biofilm formation, and its structure was atypical. A mutation in an essential gene for EPS synthesis (pssA) or deletion of several other pss genes involved in EPS synthesis completely abolished the ability of R. leguminosarum to develop a biofilm. Extracellular complementation studies of mixed bacterial cultures confirmed the role of the EPS and the modulation of the biofilm structure by the PrsD-PrsE secreted proteins. Protein analysis identified several additional proteins secreted by the PrsD-PrsE secretion system, and N-terminal sequencing revealed peptides homologous to the N termini of proteins from the Rap family (Rhizobium adhering proteins), which could have roles in cellular adhesion in R. leguminosarum. We propose a model for R. leguminosarum in which synthesis of the EPS leads the formation of a biofilm and several PrsD-PrsE secreted proteins are involved in different aspects of biofilm maturation, such as modulation of the EPS length or mediating attachment between bacteria.

* Corresponding author. Mailing address: Fundación Instituto Leloir, CONICET, and Inst. de Investigaciones Bioquímicas, FCEyN, University of Buenos Aires, Patricias Argentinas 435, (C1405BWE) Buenos Aires, Argentina. Phone: 54-11-52387500, ext. 3303. Fax: 54-11-52387501. E-mail: azorreguieta{at}leloir.org.ar.

{dagger} Present address: Department of Chemistry, Carlsberg Laboratory Gamle, Carlsberg Vej 10, DK 2500, Valby, Denmark.

Journal of Bacteriology, June 2006, p. 4474-4486, Vol. 188, No. 12
0021-9193/06/$08.00+0     doi:10.1128/JB.00246-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Joaquin, J. C., Kwan, C., Abramzon, N., Vandervoort, K., Brelles-Marino, G. (2009). Is gas-discharge plasma a new solution to the old problem of biofilm inactivation?. Microbiology 155: 724-732 [Abstract] [Full Text]  
  • Williams, A., Wilkinson, A., Krehenbrink, M., Russo, D. M., Zorreguieta, A., Downie, J. A. (2008). Glucomannan-Mediated Attachment of Rhizobium leguminosarum to Pea Root Hairs Is Required for Competitive Nodule Infection. J. Bacteriol. 190: 4706-4715 [Abstract] [Full Text]  
  • Glenn, S. A., Gurich, N., Feeney, M. A., Gonzalez, J. E. (2007). The ExpR/Sin Quorum-Sensing System Controls Succinoglycan Production in Sinorhizobium meliloti. J. Bacteriol. 189: 7077-7088 [Abstract] [Full Text]  
  • Posadas, D. M., Martin, F. A., Sabio y Garcia, J. V., Spera, J. M., Delpino, M. V., Baldi, P., Campos, E., Cravero, S. L., Zorreguieta, A. (2007). The TolC Homologue of Brucella suis Is Involved in Resistance to Antimicrobial Compounds and Virulence. Infect. Immun. 75: 379-389 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»