Table 5.

Susceptibility patterns of S. aureus MT5gyrB142 strains diploid for grlB + and mutant grlBa

Strain/plasmidType ofgrlBb in:Plasmid positioncMIC (μg/ml)d
ChromosomePlasmidCPFXNFLXOFLXSPFXNAOANOVCOU
MT5/pSK950WildNonePlasmid0.1250.50.250.06128.04.040.05.0
MT5/pBFC9BWildN470DPlasmid1.04.01.00.12128.02.010.01.25
MT5224c9/pSK950N470DNonePlasmid1.08.01.00.12128.04.05.01.25
MT5224c9/pBFISBN470DWildPlasmid0.1250.250.250.06128.04.040.05.0
MT5/pSK950WildNoneChromo.0.1250.250.25NDe NDND40.05.0
MT5/pBFC9BWildN470DChromo.0.51.00.5NDNDND20.05.0
MT5224c9/pSK950N470DNoneChromo.1.04.01.0NDNDND2.50.62
MT5224c9/pBFISBN470DWildChromo.0.251.00.5NDNDND40.05.0
  • a MT5 and MT5224c9 carry a double mutation of gyrB (Ile102Ser and Arg144Ile).

  • b Wild, wild-type gene; none, plasmid vector only; N470D, mutant gene (grlB543) encoding Asn470Asp mutation.

  • c Position of the plasmid: free in the cell (plasmid) or integrated in the chromosome (chromo.).

  • d CPFX, ciprofloxacin; NFLX; norfloxacin; OFLX, ofloxacin; SPFX, sparfloxacin; NA, nalidixic acid; OA, oxolinic acid; NOV, novobiocin; COU, coumermycin. The MICs are the means of three different transformants.

  • e ND, not determined.