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Molecular characterization of genes encoding the quinolone resistance determining regions of Malaysian Streptococcus

N Kumari1, G Subramaniam, P Navaratnam

  • 1Department of Medical Microbiology, Faculty of Medicine, University of Malaya Kuala Lumpur-50603, Malaysia.

Indian Journal of Medical Microbiology
|May 1, 2008
PubMed

Insights

This study investigated fluoroquinolone resistance in Streptococcus pneumoniae in Malaysia. A mutation in the gyrA gene was detected, suggesting potential for developing resistance, though further research is needed.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • Streptococcus pneumoniae is a significant human pathogen.
  • Fluoroquinolone antibiotics are crucial for treating S. pneumoniae infections.
  • Emergence of antimicrobial resistance is a global health concern.

Purpose of the Study:

  • To investigate mutation patterns in quinolone resistance-determining regions (QRDRs) of Streptococcus pneumoniae in Malaysia.
  • To identify potential genetic markers associated with fluoroquinolone resistance in S. pneumoniae.

Main Methods:

  • Antimicrobial susceptibility testing of 100 S. pneumoniae isolates.
  • PCR amplification of gyrA, parC, gyrB, and parE genes.
  • DNA sequencing of eight representative isolates.

Main Results:

  • 56 out of 100 isolates showed reduced susceptibility to ciprofloxacin.
  • Two sequenced isolates exhibited a point mutation in the gyrA gene at Ser81.
  • The gyrA Ser81 mutation is a known marker for fluoroquinolone resistance.

Conclusions:

  • The detection of the gyrA Ser81 mutation in Malaysian S. pneumoniae strains indicates a potential for fluoroquinolone resistance development.
  • Further studies are required to confirm the role of this mutation in conferring resistance in this region.
  • Monitoring resistance patterns is essential for effective antimicrobial therapy.

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