Figure 3.

Copper resistance assay. Differences in copper resistance between the PAO1 and ΔcopG Pseudomonas aeruginosa strains were assayed by serial dilution on copper-containing agar plates. A, single plate with 4 replicates of each dilution series. Under anaerobic conditions, the copG knockout shows increased sensitivity to copper. B, comparison of growth on plates containing 0–4 mm copper sulfate for PAO1 and ΔcopG strains under aerobic and anaerobic conditions. The average of the highest dilution allowing growth from 8 replicates (2 plates) is plotted, and error bars indicate 1 standard deviation.