Genetics of Biofilms Laboratory - URA CNRS 2172  


  HEADDr GHIGO Jean-Marc / jmghigo@pasteur.fr
  MEMBERSDr Christophe BELOIN / Dr Lionel FERRIERES / Dr Steve BERNIER/ Dr Gaelle HEMERY/ Mr Benjamin LE QUéRé / Mrs Chara KOREA / Mrs Patricia LATOUR-LAMBERT


  Annual Report

Biofilms are communities of microorganisms that develop on surfaces in most natural and artificial environments. Biofilm maturation requires cell contact with a surface and cell-cell adhesion counteracting the shear forces of the environment Figure). Biofilms are characterized by a surface covered by a high number of cells (a film) encased in a self-produced extracellular matrix, are highly heterogeneous environment, both at structural, physiological and specific levels and biofilm bacteria express still under-explored specific biological properties such as a characteristic increased tolerance to biocides

Biofilms cause sanitary and industrial nuisances.

Besides the positive ecological roles assumed by sessile microbial communities, biofilms that form in industrial and medical settings, in particular on indwelling medical devices, are difficult to eradicate and are therefore associated with both health and economic issues. During the last decade, their negative impact on human activities has stimulated research aimed at providing clues to fight detrimental biofilms

Molecular analysis of bacterial biofilm formation.

The objectives of the studies undertaken in the laboratory are to identify bacterial factors involved in the formation of commensal and pathogenic bacterial (Escherichia coli) biofilms, with particular emphasis on biofilm-specific physiological properties and competitive bacterial interactions within mixed biofilms

We use genetic, genomic and molecular biology approaches combined with different biofilm models. This has enabled us: (i) to identify several bacterial factors promoting both initial surface contacts and bacterial-bacterial interactions during the tri-dimensional development of the biofilm (pili, surface adhesins and extracellular polysaccharide); (ii) to study gene regulatory pathways involved in, or specifically associated with, biofilm formation (matrix cellulose regulation, relationships between virulence and biofilm regulation, genomic of biofilm lifestyle); and (iii) to investigate functions performed in the heterogeneous biofilm environment both in mono and multispecific contexts (horizontal gene transfer, bacterial interference and anti-adhesion molecule,  bacteriotoxin production in mixed biofilms contexts)

These approaches contribute to a better fundamental understanding of bacterial biofilm lifestyle and revealed unsuspected biological resources that may be used by E. coli species to operate within bacterial communities. Moreover, some aspects of our studies, at the interface between fundamental and clinical/applied researches could also lead, in partnership with the industry, to the development of new strategies to control or limit the extent of pathogenic or detrimental biofilms in situations in which they represent a sanitary, industrial or ecological problem

Keywords: Biofilm, Escherichia coli

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Research Interrest of the genetics of Biofilms Laboratory



  Publications

• Ulett, G.C. ;Valle, J. ; Beloin, C. ; Sherlock, O. ; Ghigo,J.M. andM. A. Schembri. (2007). Functional analysis of Antigen 43 in uropathogenic Escherichia coli reveals a role in long term persistence in the urinary tract.Infection and Immunity75 3233-3244

• Valle, J., Da Re, S., Henry, N., Fontaine, T., Balestrino, D., Latour-Lambert, P. and Ghigo, J. M. (2006) Broad-spectrum biofilm inhibition by a secreted bacterial polysaccharide Proc Natl Acad Sci U S A.103:12558-63.

• Da Re, S. and Ghigo, J. M. (2006) A CsgD-Independent Pathway for Cellulose Production and Biofilm Formation in Escherichia coli J Bacteriol.188:3073-87.

• Beloin, C., Michaelis, K., Lindner, K., Landini, P., Hacker, J., Ghigo, J. M. and Dobrindt, U. (2006) The Transcriptional Antiterminator RfaH Represses Biofilm Formation in Escherichia coli J Bacteriol.188:1316-31.

• Beloin, C., Valle, J., Latour-Lambert, P., Faure, P., Kzreminski, M., Balestrino, D., Haagensen, J. A., Molin, S., Prensier, G., Arbeille, B. and Ghigo, J. M. (2004) Global impact of mature biofilm lifestyle on Escherichia coli K-12 gene expression Mol Microbiol.51:659-74.



  Web Site

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Activity Reports 2007 - Institut Pasteur
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