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Fluoroquinolone resistance in clinical isolates of Streptococcus pneumoniae: contributions of type II topoisomerase mutations and efflux to levels of resistance.

ABSTRACT: We report on amino acid substitutions in the quinolone resistance-determining region of type II topisomerases and the prevalence of reserpine-inhibited efflux for 70 clinical isolates of S. pneumoniae for which the ciprofloxacin MIC is >/=4 microgram/ml and 28 isolates for which the ciprofloxacin MIC is

SUBMITTER: Bast DJ

PROVIDER: S-EPMC101601 | biostudies-literature | 2000 Nov

REPOSITORIES: biostudies-literature

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Fluoroquinolone resistance in clinical isolates of Streptococcus pneumoniae: contributions of type II topoisomerase mutations and efflux to levels of resistance.

Bast D J DJ Low D E DE Duncan C L CL Kilburn L L Mandell L A LA Davidson R J RJ de Azavedo J C JC

Antimicrobial agents and chemotherapy 20001101 11

We report on amino acid substitutions in the quinolone resistance-determining region of type II topisomerases and the prevalence of reserpine-inhibited efflux for 70 clinical isolates of S. pneumoniae for which the ciprofloxacin MIC is >/=4 microgram/ml and 28 isolates for which the ciprofloxacin MIC is </=2 microgram/ml. The amino acid substitutions in ParC conferring low-level resistance (MICs, 4 to 8 microgram/ml) included Phe, Tyr, and Ala for Ser-79; Asn, Ala, Gly, Tyr, and Val for Asp-83; ...[more]

PMID: 11036021

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