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Detection of the macrolide-efflux protein A gene mef(A) in Enterococcus faecalis

Karin Schwaiger1, Christina Hölzel, Johann Bauer

  • 1Chair of Animal Hygiene, Technische Universität München, Freising-Weihenstephan, Germany. karin.schwaiger@wzw.tum.de

Microbial Drug Resistance (Larchmont, N.Y.)
|May 14, 2011
PubMed

Insights

The mef(A) gene, conferring macrolide resistance, was found in Enterococcus faecalis from human and porcine sources. This highlights E. faecalis as a potential reservoir for antibiotic resistance genes.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Antimicrobial Resistance

Background:

  • Enterococci are significant pathogens and reservoirs for antibiotic resistance genes.
  • The mef(A) gene confers resistance to macrolide antibiotics.
  • Enterococcus faecalis exhibits a propensity for acquiring resistance genes.

Purpose of the Study:

  • To investigate the prevalence of the mef(A) gene in Enterococcus faecalis strains of porcine and human origin.
  • To determine if E. faecalis acts as a reservoir for macrolide resistance genes in these populations.

Main Methods:

  • Screening of 485 Enterococcus faecalis strains (239 porcine, 246 human) using polymerase chain reaction (PCR) for the mef(A) gene.
  • Isolation of strains from fecal samples of healthy individuals and a diseased pig.

Main Results:

  • The mef(A) gene was detected in 29 E. faecalis strains (10 porcine, 19 human).
  • Most mef(A)-positive strains were isolated from healthy individuals' fecal samples.
  • This is the first report of the mef(A) gene in E. faecalis outside of mating experiments.

Conclusions:

  • Enterococcus faecalis harbors the mef(A) gene, contributing to macrolide resistance.
  • E. faecalis serves as a potential reservoir for macrolide resistance, posing a clinical concern due to potential gene transfer.
  • The findings underscore the importance of monitoring E. faecalis for antibiotic resistance genes, given limited treatment options.

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