Novel Ciprofloxacin-Resistant, Nalidixic Acid-Susceptible Mutant of <i>Staphylococcus aureus</i>

Abstract

A ciprofloxacin-resistant, nalidixic acid-susceptible mutant of Staphylococcus aureus (F145) contained no mutations within gyrA, gyrB, grlA, and grlB or within norA or its promoter region. MICs and accumulation studies suggest the role of a novel multidrug efflux pump.