Interspecies Recombination Occurs Frequently in Quinolone Resistance-Determining Regions of Clinical Isolates of Streptococcus pyogenes

ABSTRACT

Fluoroquinolone resistance in Streptococcus pyogenes has been reported only anecdotally, but a recent Belgian surveillance study found a rate of nonsusceptibility of 5.4%. From an analysis of these isolates, we show that interspecies horizontal gene transfer within the parC quinolone resistance-determining region is a frequent phenomenon that might contribute to fluoroquinolone resistance.