In Vitro Exchange of Fluoroquinolone Resistance Determinants betweenStreptococcus pneumoniaeand Viridans Streptococci and Genomic Organization of theparE‐parCRegion inS. mitis

Abstract

Transfer of fluoroquinolone (FQ) resistance determinants between Streptococcus pneumoniae and viridans streptococci was explored by transformation in vitro. One-step FQ-resistant parC mutants were selected, and resistance could be transferred from DNA from S. oralis, S. mitis, S. sanguis, and S. constellatus to S. pneumoniae, with frequencies of 10 ⁻³ to 90% homology with that of S. pneumoniae. The efficient interspecific transfer of quinolone resistance determinants in vitro leads us to anticipate their dissemination in the clinical setting.