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Updated: May 22, 2026
05:02
A 1.5 Hour Procedure for Identification of Enterococcus Species Directly from Blood Cultures
Published on: February 10, 2011
Non-beta-lactamase-producing penicillin-resistant Enterococcus faecium in a clinical setting
Abstract:
Six clinical isolates of Enterococcus faecium highly resistant to penicillin are reported. These strains did not produce beta-lactamase and no plasmid DNA could be detected. It is postulated that the mechanism of resistance is one or more chromosomally mediated alterations of penicillin-binding proteins.
Insights
Penicillin resistance in Enterococcus faecium strains was investigated. The study suggests chromosomally mediated alterations in penicillin-binding proteins are the likely cause of this high-level resistance.
Area of Science:
- Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Enterococcus faecium is a significant nosocomial pathogen.
- Penicillin resistance is a growing concern in treating Enterococcus faecium infections.
Purpose of the Study:
- To investigate the mechanism of high-level penicillin resistance in clinical isolates of Enterococcus faecium.
Main Methods:
- Analysis of six clinical Enterococcus faecium isolates exhibiting high penicillin resistance.
- Testing for beta-lactamase production.
- Plasmid DNA detection.
Main Results:
- None of the resistant strains produced beta-lactamase.
- No plasmid DNA was detected in any of the isolates.
- High-level penicillin resistance was observed.
Conclusions:
- The mechanism of penicillin resistance in these Enterococcus faecium strains is likely due to chromosomally mediated alterations.
- Penicillin-binding proteins are implicated as the target of these alterations.
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