Serine-to-asparagine substitution in the GyrA gene leads to quinolone resistance in moxifloxacin-exposed Chlamydia pneumoniae.
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.
Rupp
Jan
J
Institute of Medical Microbiology and Hygiene, University of Luebeck, Ratzeburger Allee 160, 23538 Luebeck, Germany.
Gebert
Andreas
A
Solbach
Werner
W
Maass
Matthias
M
D000890:Anti-Infective Agents / Q000494:pharmacology*; D001216:Asparagine; D001372:Aza Compounds / Q000494:pharmacology*; D016993:Chlamydophila pneumoniae / Q000187:drug effects* / Q000254:growth & development; D027081:DNA Gyrase / Q000235:genetics*; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D024841:Fluoroquinolones; D006801:Humans; D008826:Microbial Sensitivity Tests; D000077266:Moxifloxacin; D017354:Point Mutation; D011804:Quinolines / Q000494:pharmacology*; D015363:Quinolones / Q000494:pharmacology*; D012692:Serial Passage; D012694:Serine
D000890:Anti-Infective Agents; D001372:Aza Compounds; D024841:Fluoroquinolones; D011804:Quinolines; D015363:Quinolones; D012694:Serine; D001216:Asparagine; D027081:DNA Gyrase; D000077266:Moxifloxacin