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Bone Marrow-derived Macrophage Production
07:06

Bone Marrow-derived Macrophage Production

Published on: November 22, 2013

Characterization of two signal transduction systems involved in intracellular macrophage survival and environmental

Cécile Muller1, Maurizio Sanguinetti, Eliette Riboulet

  • 1USC INRA 2017, Microbiologie de l'Environnement, EA 956, IRBA, Université de Caen, Caen, France.

Journal of Molecular Microbiology and Biotechnology
|October 25, 2007
PubMed

Insights

Enterococcus faecalis two-component systems (TCS) influence macrophage survival. Specific TCS mutants show altered susceptibility to intracellular environments and oxidative stress, impacting virulence.

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Signal Transduction

Background:

  • Enterococcus faecalis is an opportunistic pathogen.
  • Intracellular survival within macrophages is a key virulence factor.
  • Two-component systems (TCS) regulate bacterial adaptation and survival.

Purpose of the Study:

  • To investigate the role of E. faecalis TCS in intracellular survival within mouse peritoneal macrophages.
  • To characterize specific TCS involved in stress response and virulence.

Main Methods:

  • Construction and phenotypic analysis of E. faecalis response regulator mutants.
  • Assessment of bacterial survival in mouse peritoneal macrophages.
  • Gene expression analysis under phosphate deprivation and oxidative stress conditions.

Main Results:

  • Three out of eight response regulator mutants exhibited increased susceptibility to macrophage killing.
  • One mutant showed enhanced resistance to intracellular survival.
  • The Err04-Ehk04 TCS is involved in phosphate metabolism and autoregulation.
  • The Err06-Ehk06 TCS mediates oxidative stress response and influences catalase gene expression.

Conclusions:

  • Specific E. faecalis TCS are critical for survival within macrophages.
  • The Err04-Ehk04 and Err06-Ehk06 systems play distinct roles in nutrient acquisition and stress resistance, respectively.
  • Understanding these TCS provides insights into E. faecalis pathogenesis.

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