Table 2.

Changes in MICs in relationship to Mcc24 exposure in a representative experiment

TreatmentStrainaMIC (μg/ml) ofb:Zone of inhibition around MC4100pGOB18 disk
CIPTETCHLRIF
Two exposures to disks soaked in MC4100pGOB18SL1344/CFP/marR border colonies0.1254212.5Yes
17 exposures to disks soaked in MC4100pGOB18SL1344/CFP/marR border colonies0.25NDNDNDYes
18 exposures to disks soaked in MC4100pGOB18SL1344/CFP/marR border colonies2163250No
17 exposures to disks soaked in MC4100pGOB18 followed by another exposure in the presence of 0.2% arabinoseSL1344/CFP/marR border colonies0.5NDNDNDYes
17 exposures to disks soaked in MC4100pGOB18 and then two more exposures in the presence of 0.2% arabinoseSL1344/CFP/marR border colonies0.25NDNDNDYes
17 exposures to disks soaked in MC4100pGOB18 one exposure to 0.2% arabinose, and then 2 to 3 additional exposures to disks soaked in MC4100pGOB18SL1344/CFP/marR border colonies2163250No
18 expansions without exposure to disks soaked in MC4100pGOB18SL1344/CFP/marRedge colonies0.1254212.5Yes
50 expansions without exposure to disks soaked in MC4100pGOB18SL1344/CFP/marR edge colonies0.1254212.5Yes
  • a “Border” indicates that colonies were selected from the border of the zone of inhibition, and “edge” indicates that colonies were selected from the edge of the agar plate.

  • b Concentrations of antibiotics were as described in Table 1, note a. ND, not determined.