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Updated: Sep 26, 2026

Using the Overlay Assay to Qualitatively Measure Bacterial Production of and Sensitivity to Pneumococcal Bacteriocins
06:05

Using the Overlay Assay to Qualitatively Measure Bacterial Production of and Sensitivity to Pneumococcal Bacteriocins

Published on: September 30, 2014

[Streptococcus pneumoniae strains resistance to macrolide, lincosamide, streptogramin, oxazolidinone and ketolide]

Burçin Sener1, Ozgen Köseoğlu, Inci Fişenk

  • 1Hacettepe Universitesi Tip Fakültesi Mikrobiyoloji ve Klinik Mikrobiyoloji Anabilim Dali, Ankara.

Mikrobiyoloji Bulteni
|March 26, 2003
PubMed

Insights

Antimicrobial resistance in Streptococcus pneumoniae is rising, particularly macrolide resistance in penicillin-resistant strains. New agents like streptogramins, oxazolidinones, and ketolides show promise against resistant pneumococci.

Area of Science:

  • Clinical Microbiology
  • Infectious Diseases
  • Pharmacology

Context:

  • Increasing antimicrobial resistance in Streptococcus pneumoniae over two decades.
  • Reports indicate a rise in macrolide resistance among penicillin-resistant S. pneumoniae.
  • Evolution of resistance necessitates novel antimicrobial agents.

Purpose:

  • Determine the prevalence of macrolide resistance in pneumococci in a Turkish University hospital.
  • Evaluate the activity of new agents (streptogramins, oxazolidinones, ketolides) against resistant pneumococci.

Summary:

  • 264 pneumococcal isolates tested against penicillin, macrolides, clindamycin, quinupristin/dalfopristin, linezolid, and telithromycin.
  • Penicillin resistance: 7.6%; intermediate: 40%. Macrolide resistance: 13.6-15.9%. Higher resistance in penicillin-resistant strains.
  • No resistance to quinupristin/dalfopristin, linezolid, telithromycin, with minimal exceptions.

Impact:

  • Significant prevalence of macrolide-resistant pneumococci identified in the hospital.
  • Streptogramins, oxazolidinones, and ketolides demonstrate potential as alternative treatments for resistant pneumococcal infections.

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