© Pierre Gounon
Entrée de Listeria dans une cellule épithéliale (Grossissement X 10000). Image colorisée.

Bacteria-Cell Interactions


Our Unit investigates the molecular and cellular basis of the infection by Listeria monocytogenes, a model pathogen for the study of the intracellular parasitism. L. monocytogenes is responsible for severe foodborne infections. This bacterium is characterized by its ability to cross three host barriers -the intestinal, blood-brain or feto-placental barriers- and to invade several cell types in which it multiplies. L. monocytogenes moves in the cytosol of infected cells and spreads from cell to cell using an original propelling process; i.e. cell actin polymerization at one pole of the bacteria.

Our present activity focuses on:

  1. the identification and characterization of new non-coding RNAs involved in virulence, as well as new RNA-mediated regulations;
  2. the investigation of new molecular pathways involved in bacterial entry into host cells and cell-to-cell spread;
  3. organelle dynamics during infection;
  4. the systematic analysis of post-translational modifications of host molecules during infection, in particular SUMOylation;
  5. chromatin remodeling upon infection;
  6. the characterization of new bacterial virulence factors identified by post-genomic approaches or by their effect on cellular responses;
  7. in-depth understanding of the intestinal phase of the L. monocytogenes infection by analyzing the impact of commensals on L. monocytogenes growth and the bacterial effect on the intestinal tissue.

In many of these research themes, we try to generalize our findings to other bacterial models.

The “Unité des Interactions Bactéries-Cellules” (UIBC) is associated with Inserm (INSERM U604) and with INRA (INRA USC2020)




Former Members

Program Projects


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Pictures & Media

InC secretion in HeLa cells infected with Listeria


Bacteria-cell interactions Unit – INSERM U604 – INRA USC2020
Department of Cell biology and Infection
25 rue du Docteur Roux -75724 PARIS Cedex 15-France.
Tel : + 33 (1) 45 68 88 41 (secretary: + 33 (1) 40 61 30 32) Fax : + 33 (1) 45 68 87 06
E-mail : pascale.cossart@pasteur.fr