FIG. 7.

Chitinase activities of supernatants from PAO1 cultures grown to an OD₆₀₀ of 2.0 either without antibiotics (black bar) or in the presence of: 2 μg/ml AZM (bar with horizontal lines), 8 μg/ml AZM (bar with vertical lines), 0.25 μg/ml CFT (dark gray bar), or 0.04 μg/ml CPR (light gray bar). The chitinase activity of the ΔlasI-ΔrhlI mutant of PAO1 is also shown (white bar). The graph is based on the average results of three independent experiments. *, P < 0.05; **, P < 0.01 (Dunnett's post test).