Serine-to-asparagine substitution in the GyrA gene leads to quinolone resistance in moxifloxacin-exposed Chlamydia pneumoniae

Antimicrob Agents Chemother. 2005 Jan;49(1):406-7. doi: 10.1128/AAC.49.1.406-407.2005.

Abstract

Quinolone resistance of Chlamydia pneumoniae has not been described previously. Serial subcultures of C. pneumoniae under increasing moxifloxacin concentrations (0.0125 to 6.4 mg/liter) resulted in a 256-fold MIC increase compared to moxifloxacin-naive strains. GyrA gene sequencing revealed a novel point mutation with a Ser-->Asn substitution. Subcultures under rifalazil and macrolides did not alter the respective MICs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Infective Agents / pharmacology*
  • Asparagine
  • Aza Compounds / pharmacology*
  • Chlamydophila pneumoniae / drug effects*
  • Chlamydophila pneumoniae / growth & development
  • DNA Gyrase / genetics*
  • Dose-Response Relationship, Drug
  • Drug Resistance, Bacterial*
  • Fluoroquinolones
  • Humans
  • Microbial Sensitivity Tests
  • Moxifloxacin
  • Point Mutation*
  • Quinolines / pharmacology*
  • Quinolones / pharmacology*
  • Serial Passage
  • Serine

Substances

  • Anti-Infective Agents
  • Aza Compounds
  • Fluoroquinolones
  • Quinolines
  • Quinolones
  • Serine
  • Asparagine
  • DNA Gyrase
  • Moxifloxacin