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Drug efflux and parC mutations are involved in fluoroquinolone resistance in viridans group streptococci.

ABSTRACT: Nine ciprofloxacin-resistant viridans group streptococci isolated from asymptomatic carriers were analyzed. Identification to the species level by using three different commercial systems and a PCR-based approach was inconsistent. The nucleotide sequences of fragments of the parC, parE, gyrA, and gyrB genes showed considerable intra- and interspecies variations, and these variations mainly involved silent mutations. Three isolates had changes in Ser-79 of ParC (to Phe or Tyr). Phenotypic characterization indicated that eight of the nine isolates had a putative efflux mechanism that would confer low-level resistance to ciprofloxacin.

SUBMITTER: Ferrandiz MJ

PROVIDER: S-EPMC89512 | biostudies-literature | 1999 Oct

REPOSITORIES: biostudies-literature

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Drug efflux and parC mutations are involved in fluoroquinolone resistance in viridans group streptococci.

Ferrándiz M J MJ Oteo J J Aracil B B Gómez-Garcés J L JL De La Campa A G AG

Antimicrobial agents and chemotherapy 19991001 10

Nine ciprofloxacin-resistant viridans group streptococci isolated from asymptomatic carriers were analyzed. Identification to the species level by using three different commercial systems and a PCR-based approach was inconsistent. The nucleotide sequences of fragments of the parC, parE, gyrA, and gyrB genes showed considerable intra- and interspecies variations, and these variations mainly involved silent mutations. Three isolates had changes in Ser-79 of ParC (to Phe or Tyr). Phenotypic charact ...[more]

PMID: 10508036

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