Table 4.

Susceptibility patterns of S. aureus RN4220gyrB142 strains diploid for grlAa

Strain/plasmidgrlAb MIC (μg/ml)c
ChromosomePlasmidCiprofloxacinNorfloxacinNovobiocinCoumermycin
BF2/pSK950WildNone0.51.020.05.0
BF2/pBFMTAWildAla116Glu1.04.05.01.25
BF2/pBFC2AWildAla116Pro1.04.05.01.25
BF2/pBFC4AWildSer80Phe1.04.010.02.5
BF7/pSK950Ala116GluNone1.08.05.01.25
BF7/pBFISAAla116GluWild0.250.520.05.0
BF8/pSK950Ala116ProNone1.04.05.01.25
BF8/pBFISAAla116ProWild0.250.520.05.0
BF9/pSK950Ser80PheNone2.08.020.05.0
BF9/pBFISASer80PheWild0.250.520.05.0
  • a BF2, BF7, BF8, and BF9 carry the double-mutation (Ser102 and Ile144) gyrB gene.

  • b Wild, wild-type gene; none, plasmid vector only.

  • c The MICs are the mean values for at least three different transformants.