gyrA Polymorphism in Campylobacter jejuni: Detection of gyrA Mutations in 162 C. jejuni Isolates by Single-Strand Conformation Polymorphism and DNA Sequencing

ABSTRACT Mutations in the quinolone resistance-determining region of the gyrA gene from 138 ciprofloxacin-resistant (MIC, ≥4 μg/ml) and 24 ciprofloxacin-susceptible (MIC, ≤1 μg/ml) clinical Campylobacter jejuni isolates were subjected to single-strand conformation polymorphism analysis and sequencing. All of the isolates could be assigned to three genotypic clusters based on silent mutations. All resistant isolates had a point mutation at codon 86.