FIG. 2.

Effect of media on biofilm growth. Biofilms of 12 P. aeruginosa CF isolates were grown on pegs in three different media (M63 minimal medium plus 0.4% arginine, gray bars; CAMHB, solid bars; and CAMHB plus 0.4% arginine, open bars) and stained with crystal violet. Bars represent the mean OD₅₉₀ values, and error bars represent the standard deviations. Isolates 1 to 6 were nonmucoid, and isolates 7 to 12 were mucoid, with eight replicates tested per isolate. The P values from pairwise comparisons included the following (unadjusted for multiple comparisons): CAMHB versus minimal (P = 0.02), CAMHB plus arginine versus minimal (P = 0.04), and CAMHB versus CAMHB plus arginine (P = 0.63).