The role of Legionella pneumophila efflux pumps in biocides and host’s resistance
type: Dataset
description: Bacterial multi-drug resistance is of major concern in the case of clinic. One of the resistance mecanisms used by bacteria is the efflux of noxious compounds out of the cell thanks to inner membran proteins called efflux pumps. This proteins belong to five families (MFS, RND, MATE, SMR and ABC) and can function in close association with two partners (periplasmic protein and outer membrane protein) to form a canal. In our new research axis based on the study of the drug resistance of the bacterium Legionella pneumophila, we conducted a bioinformatical approach to identify efflux pumps proteins coded by the sequenced genome of three strains (strains Lens, Paris and Philadelphia). Our goal was to study the role of this proteins in Legionella drug resistance and in its virulence. The bioinformatic approach data allowed us to choose one or several genes coding for potential efflux pump components for genetic invalidation by an homologousrecombination strategy. The bacterial mutants were exposed to different noxious compounds in order to know ifthe target genes invalidated were implicated in the efflux of drugs. One of this mutants, strain MF201, which isdeleted for the gene encoding a protein homologous to E. coli TolC protein, revealed to be 2 to 16 times moresensitive to the drug tested compared to the wild-type strain. Furthermore, this mutant showed an importantvirulence defect in Acanthamoeba castellanii, Dictyostelium discoideum and U937 macrophages. This first resultsmeans that the TolC-like protein of Legionella could be a key factor in host-pathogen interaction and stronglysuggests a link between multi-drug resistance and virulence. We also initiated a transcriptomic approach to studyefflux pump genes expression in order to understand their role during the infectious cycle of Legionella.
landing page: https://theses.hal.science/tel-00810657
identifier: NNT: 2010LYO10067
keyword: drug-resistance
keyword: efflux
keyword: host-pathogen-interaction
keyword: infoeu-reposemanticsdoctoralthesis
keyword: legionella-pneumophila
keyword: relation-hote-pathogene
keyword: resistance-aux-drogues
keyword: sdvsalife-sciences-q-bioagricultural-sciences
keyword: theses
keyword: virulence
issued: 2026-05-11T14:46:34.710799
modified: 2026-05-11T14:46:34.710804
language: fr
contact point: Organization
  fn: CCSD

test_moissonnage_selune
type: Agent

The role of Legionella pneumophila efflux pumps in biocides and host’s resistance
type: Distribution
format: HTML
access URL: https://theses.hal.science/tel-00810657
issued: 2026-05-11T14:46:34.734730
modified: 2026-05-11T14:46:34.691886