FIG 3.

Time-kill assays with antibiotics and DFP that demonstrate enhanced efficacy against E. coli. E. coli CP9 was cultured in 5 ml of BHI medium overnight at 37°C with vigorous shaking. After 18 h, bacteria were subcultured at a starting OD₆₀₀ of 0.01 in 5 ml of CAMHB supplemented with an antibiotic (panel A, AMP at 2.5 μg/ml; panel B, CTX at 62.5 ng/ml; panel C, CHL at 250 μg/ml; panel D, MET at 1 mg/ml; panel E, VAN at 250 μg/ml) or with an antibiotic with DFP at 150 μg/ml or not supplemented at all. The CFU counts of the cultures were determined by 10-fold serial dilution and drip plating of 20 μl of each diluent at the times indicated. Data are the mean values and standard deviations from three independent experiments.