Antibiotic susceptibility testing and disinfectant challenge assays.

<p>A) The Kirby Bauer disc diffusion assay was performed with different antibiotics (CA30, CPM30, CI30, CL30, VA10, TB10, AMK10, S10, NA30, TR5, E15 and T30) using commercial discs. Data for representative drugs from each class have been shown here. B) Sensitivity towards benzalkonium chloride by WT and <i>phoB</i>^KP mutant when cells were exposed to different concentrations of the disinfectant (3.2 µg/ml, 6.4 µg/ml, 12.8 µg/ml, 25.6 µg/ml, 51.2 µg/ml). C) Tolerance of WT and <i>phoB</i>^KP to different concentration of chlorhexidine. The percent survival was calculated by comparison of viable cells in control. The datas are the means of measurements made in triplicate performed three times. *, significant difference (P<0.05, Student t test).