FIG 1.

(A) An isobologram generated from checkerboard assays where AB5075 was grown with increasing concentrations of SPR741 and rifampin. (B) Time-kill assay of SPR741, rifampin, and combinations against XDR-A. baumannii. AB5075 was grown overnight in CAMHB, then subcultured into CAMHB for 2 h. Cultures were inoculated 1:10 into CAMHB alone or with 2.0 μg/ml SPR741, 1.0 μg/ml rifampin, or both SPR741 and rifampin at their respective concentrations. Time points were taken at 0, 2, 4, 6, and 24 h, and samples were plated for CFU. Only the combination of rifampin and SPR741 was statistically significant (red line), as tested by two-way ANOVA (P = 0.0048).