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Characterization of macrolide efflux pump mef subclasses detected in clinical isolates of Streptococcus pyogenes isolated between 1999 and 2005.

ABSTRACT: The macrolide efflux mechanism of resistance, mef, was characterized in community-acquired respiratory tract infections with Streptococcus pyogenes. Fifty-four (4.6%) M phenotype isolates were screen tested as negative for mef(A). Of these 54 isolates, 5 (0.4%), 27 (2.3%), and 1 (0.1%) were considered to be mef(I) positive, a novel mosaic variant of mef, or a novel subclass of mef, respectively. This study shows (i) the definitive presence of mef(E) in S. pyogenes and its global distribution, (ii) the presence of a mosaic variant of mef composed of mef(A) and mef(E), (iii) the previously undescribed presence of mef(I) in S. pyogenes, and (iv) the presence of a novel subclass of mef in S. pyogenes.

SUBMITTER: Blackman Northwood J

PROVIDER: S-EPMC2681526 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature

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Characterization of macrolide efflux pump mef subclasses detected in clinical isolates of Streptococcus pyogenes isolated between 1999 and 2005.

Blackman Northwood J J Del Grosso M M Cossins L R LR Coley M D MD Creti R R Pantosti A A Farrell D J DJ

Antimicrobial agents and chemotherapy 20090302 5

The macrolide efflux mechanism of resistance, mef, was characterized in community-acquired respiratory tract infections with Streptococcus pyogenes. Fifty-four (4.6%) M phenotype isolates were screen tested as negative for mef(A). Of these 54 isolates, 5 (0.4%), 27 (2.3%), and 1 (0.1%) were considered to be mef(I) positive, a novel mosaic variant of mef, or a novel subclass of mef, respectively. This study shows (i) the definitive presence of mef(E) in S. pyogenes and its global distribution, (i ...[more]

PMID: 19258262

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