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Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43
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Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43

Published on: September 11, 2020

Ribosomal mutations conferring resistance to macrolides in Streptococcus pneumoniae clinical strains isolated in

Ralf René Reinert1, Angela Wild, Peter Appelbaum

  • 1Institute of Medical Microbiology, National Reference Center for Streptococci, Aachen, Germany. reinert@rwth-aachen.de

Antimicrobial Agents and Chemotherapy
|June 25, 2003
PubMed

Insights

Seven German pneumococcal strains exhibited unusual macrolide resistance due to 23S rRNA mutations and ribosomal protein alterations. These findings highlight novel resistance mechanisms in Streptococcus pneumoniae.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • Macrolide antibiotics are crucial for treating Streptococcus pneumoniae infections.
  • Emerging antibiotic resistance poses a significant public health threat.
  • Understanding resistance mechanisms is vital for developing effective treatment strategies.

Purpose of the Study:

  • To investigate the molecular basis of an unusual macrolide resistance phenotype observed in German pneumococcal isolates.
  • To identify genetic alterations associated with this novel resistance.

Main Methods:

  • Analysis of 4281 pneumococcal isolates.
  • Phenotypic characterization of macrolide resistance.
  • Genomic analysis, including sequencing of 23S rRNA and ribosomal protein genes (L4 and L22).

Main Results:

  • Seven pneumococcal strains displayed an unusual macrolide resistance phenotype.
  • These strains harbored multiple mutations in the 23S rRNA gene.
  • Alterations in the L4 ribosomal protein were identified in these resistant isolates.
  • One isolate also presented an amino acid change in the L22 ribosomal protein.

Conclusions:

  • The study identified novel genetic determinants conferring macrolide resistance in Streptococcus pneumoniae.
  • Multiple mutations in 23S rRNA combined with alterations in ribosomal proteins (L4 and L22) contribute to this resistance.
  • These findings enhance our understanding of pneumococcal antibiotic resistance mechanisms.

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