Table 4.

Characteristics of mutants of S. aureus ISP794 selected with premafloxacin

Strain or mutantMIC (μg/ml) ofd:Mutation in designated gene
PRFXCPFXNOVNAEBgrlAgyrAgrlBgyrBnorAb
ISP7940.0004–0.0080.125–0.250.064–0.12864–1282.0–4.0
Single-step mutants
 P40.0321.00.064128–2564.0Arg43CysNoneNoneNoneNone
 P50.0642.00.0642562.0Ala116GluNoneNoneNoneNone
 P60.0321.00.0642562.0Pro157LeuMet538IleNoneNoneNone
 P100.0321.00.032–0.0641282.0Ala176ThrNoneNoneNoneNone
 P210.0321.00.0641284.0Asp69TyrNoneNoneNoneNone
Serial-passage mutants
 PS10.516.00.0321282.0Ser80Phea Ser84Leua
 PS20.516.00.0321282.0Ser80Phea Ser84Leua
 PS30.58.0–6.00.0642564.0–8.0Ala176ThrSer84Leua Nonea AAAG insertionc
  • a QRDR.

  • b Promoter region of norA.

  • c Insertion is between the 95th and 96th nucleotide upstream of the ATG start codon of norA.

  • d Abbreviations: PRFX, premafloxacin; CPFX, ciprofloxacin; NOV, novobiocin; NA, nalidixic acid; EB, ethidium bromide.