Table 1.

Inhibitory effects of fluoroquinolones on S. pneumoniae gyrase, topoisomerase IV, and growth of S. pneumoniae 7785

QuinoloneIC50(μM)CC25 (μM) for DNA breakageaMICb(μM) for strain 7785
SupercoilingDecatenationGyraseTopoisomerase IV
Ciprofloxacin4010–20801.02.7
Sparfloxacin4010–20801.00.64
Clinafloxacin2.51–2.52.50.10.31
  • a Concentration of fluoroquinolone that converts 25% of the input pBR322 DNA to the linear form in the presence of gyrase or topoisomerase IV.

  • b Taken from reference 32.