Figure 4. Counterselection with a pathway inhibitor is also applicable to A. baumannii.

(a) Schematic of the pathway for LPS biogenesis and the target of colistin in the pathway. (b) A ΔlpxC strain is resistant to 10 μg/mL colistin, which is lethal to wildtype. Complementation with plpxC (pWH1266-P_native-lpxC) restored the colistin-susceptible phenotype. (c) Schematic of the method and targeting plasmid used for allelic exchange of the efflux pump adeFGH locus in A. baumannii. (d) Schematic of the method used for mating-out for A. baumannii strains. The donor and recipient cultures were harvested at early-log phase (OD₆₀₀=0.2) and mixed at a volumetric ratio of 1:4.