Drug sensitivity of fluoroquinolone derivatives. Dd2ΔGyrA clone exhibits similar inhibition and IPP-rescue profiles when tested with ciprofloxacin, pefloxacin, rufloxacin, norfloxacin, levofloxacin, trovafloxacin, and difloxacin. No significant delayed-death or IPP-rescue effects were seen in the Dd2ΔGyrA when tested with moxifloxacin or nadifloxacin. The bars were derived from EC50 curves at many different inhibitor concentrations.