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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
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EfaR is a major regulator of Enterococcus faecalis manganese transporters and influences processes involved in host

M C Abrantes1, J Kok, M de F Lopes

  • 1Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal.

Infection and Immunity
|January 9, 2013
PubMed

Insights

Manganese metalloregulator EfaR controls virulence in Enterococcus faecalis, a cause of endocarditis. Its absence impairs biofilm formation, macrophage survival, and oxidative stress tolerance, linking manganese to pathogenicity.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Pathogenesis

Background:

  • Metal ions, especially manganese, significantly influence bacterial pathogenicity.
  • The role of manganese-dependent proteins in Enterococcus faecalis, a nosocomial pathogen causing endocarditis, remains largely unexplored.

Purpose of the Study:

  • To investigate the function of the metalloregulator EfaR in Enterococcus faecalis.
  • To elucidate the role of manganese homeostasis in Enterococcus faecalis virulence.

Main Methods:

  • Genetic inactivation of the efaR gene in Enterococcus faecalis.
  • Analysis of gene expression regulated by EfaR.
  • Assessment of biofilm formation, macrophage survival, and oxidative stress tolerance in wild-type and mutant strains.

Main Results:

  • EfaR, a DtxR/MntR family metalloregulator, controls manganese-dependent gene expression in Enterococcus faecalis.
  • Inactivation of efaR significantly impairs biofilm formation.
  • efaR mutants exhibit reduced survival within macrophages and decreased tolerance to oxidative stress.

Conclusions:

  • EfaR is a critical modulator of Enterococcus faecalis virulence.
  • Manganese homeostasis is directly linked to the pathogenicity of Enterococcus faecalis.
  • EfaR represents a potential therapeutic target for combating enterococcal infections.

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