Stability of fluoroquinolone resistance in Streptococcus pneumoniae clinical isolates and laboratory-derived mutants.
نویسندگان
چکیده
The stability of fluoroquinolone resistance in Streptococcus pneumoniae was evaluated in laboratory-derived mutants and clinical isolates. Isolates with various genotypes and phenotypes were subcultured for 20 days on antibiotic-free media and were monitored by E-tests to identify any alterations in resistance. Fluoroquinolone resistance mechanisms, whether efflux or chromosomally mediated, remained stable in both clinical and laboratory-derived mutants.
منابع مشابه
Clinically relevant fluoroquinolone resistance due to constitutive overexpression of the PatAB ABC transporter in Streptococcus pneumoniae is conferred by disruption of a transcriptional attenuator
OBJECTIVES Constitutive overexpression of patAB has been observed in several unrelated fluoroquinolone-resistant laboratory mutants and clinical isolates; therefore, we sought to identify the cause of this overexpression. METHODS Constitutive patAB overexpression in two clinical isolates and a laboratory-selected mutant was investigated using a whole-genome transformation approach. To determi...
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 49 2 شماره
صفحات -
تاریخ انتشار 2005