Related Experiment Video
Updated: Sep 30, 2026

Antibiotic Efficacy Testing in an Ex vivo Model of Pseudomonas aeruginosa and Staphylococcus aureus Biofilms in the Cystic Fibrosis Lung
Published on: January 22, 2021
In vitro activity of linezolid, synercid and telithromycin against genetically defined high level
J L Muñoz Bellido1, M N Gutiérrez Zufiaurre, F J Sánchez Hernández
1Departamento de Medicina Preventiva, Salud Pública y Microbiología Médica, Universidad de Salamanca, Salamanca, Spain.
Abstract:
The in vitro activity of levofloxacin, moxifloxacin, gatifloxacin, erythromycin, telithromycin, linezolid, synercid and vancomycin was measured against 36 genetically defined, gyrA/grlA double mutant MRSA clinical strains with an MIC to ciprofloxacin > or = 8 mg/l. The three newer fluoroquinolones tested were more active than ciprofloxacin. Resistance rates for levofloxacin and gatifloxacin were high (44.5 and 36.1%, respectively). All the strains were moxifloxacin-susceptible, though most of them had MICs close to the break point. All the strains were intermediate or resistant to erythromycin and most were also resistant to telithromycin. No strains were resistant to linezolid, synercid or vancomycin (MIC(90): 2, 1 and 2 mg/l, respectively).
Related Concept Videos
Mechanism of Antibiotic Resistance in MRSA
Clinical Significance of Antibiotic Resistance
Inhibitors of Bacterial DNA Synthesis
Gene Regulation in Microbial Communities: Quorum Sensing
Development of Antibiotic Resistance
