A Transporter Interactome Is Essential for the Acquisition of Antimicrobial Resistance to Antibiotics
Fig 4
The role of the transporters in maintenance of high-level resistance.
A. Solid phenotype in the presence of 400 μM norfloxacin reveals a small but distinct difference in the resistance of ΔacrB-EV18 compared to WT-EV18. The suppliers are not required for maintenance of the high-level resistance of WT-EV18 to norfloxacin. B. Solid phenotype in the presence of 30 μM norfloxacin. Nil strains of acrB generated after 5, 10 and 18 days of evolution revealed that it plays an important role in maintenance of high-level resistance at every stage. However, after a short exposure to high norfloxacin (50 μM), resistance increases again. Nil strains were generated by deletion of acrB (WT-EV18-ΔacrB) and of the three suppliers (WT-EV18-Δ3) as described under Experimental Procedures.