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Updated: May 7, 2026
05:02
A 1.5 Hour Procedure for Identification of Enterococcus Species Directly from Blood Cultures
Published on: February 10, 2011
Activity of ceftaroline against Enterococcus faecium PBP5.
Xavier Henry1, Oliver Verlaine, Ana Amoroso
1Bacterial Physiology and Genetics Unit, Center for Protein Engineering, Life Science Department, University of Liège, Liège, Belgium.
Antimicrobial Agents and Chemotherapy
|September 25, 2013
Summary
Ceftaroline effectively kills ampicillin-resistant Enterococcus faecium by rapidly inactivating the essential PBP5 protein. This finding offers new insights into treating resistant bacterial infections.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Enterococcus faecium is an opportunistic pathogen often resistant to beta-lactam antibiotics.
- Penicillin-binding protein 5 (PBP5) in E. faecium has low affinity for beta-lactams and is often mutated in resistant strains.
- Ceftaroline has shown limited efficacy against beta-lactam-resistant E. faecium previously.
Purpose of the Study:
- To investigate the activity of ceftaroline against a laboratory-derived ampicillin-resistant E. faecium mutant.
- To determine the interaction of ceftaroline with PBP5 in this resistant strain.
Main Methods:
- Construction of an ampicillin-resistant E. faecium mutant overproducing wild-type PBP5.
- Assessment of ceftaroline's killing activity against the mutant strain.
- Comparison of PBP5 inactivation rates by ceftaroline, benzylpenicillin, and ceftobiprole.
Main Results:
- Ceftaroline demonstrated significant killing activity against the ampicillin-resistant E. faecium mutant.
- Ceftaroline inactivated PBP5 more rapidly than benzylpenicillin.
- Ceftaroline also inactivated PBP5 faster than ceftobiprole.
Conclusions:
- Ceftaroline exhibits potent bactericidal activity against ampicillin-resistant E. faecium strains.
- Rapid inactivation of PBP5 is the mechanism by which ceftaroline exerts its killing effect.
- These findings suggest potential for ceftaroline in treating E. faecium infections, even those with beta-lactam resistance.
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