TABLE 2

MICs of TLV, VAN, and DAP for the parent strains and in vitro-derived TLVr mutants obtained by serial passage with subinhibitory concentrations of TLV for 40 daysa

StrainMIC (μg/ml)
Day 0Day 40
TLVVANDAPTLVVANDAP
ATCC 259130.0641.50.25348
TMH 50070.04720.751.568
AMT 0114-480.04720.75266
WIS 6640.032211.536
  • a As shown, a 3- to 4-fold increase in the VAN MIC (from 1.5 to 6 μg/ml) and an 8- to 10-fold increase in DAP MICs (0.25 to 8 μg/ml) were determined, suggesting potential cross-resistance between TLV, VAN, and DAP antibiotics.