FIG. 6.

Impact of rhlI mutation on biofilm formation in Fe-rich and Fe-limited media. The P. aeruginosa RhlI⁺ parent strain K2589 in iron-rich (1% TSB) (A) and iron-limited (1% TSB plus 25 μg/ml lactoferrin) (B) media, the rhlI mutant K2590 in iron-rich (C) and iron-limited (D) media, K2590 carrying rhlI plasmid pGP003 in iron-rich (E) and iron-limited (F) media, and K2590 in Fe-limited medium supplemented with 2 μM C4-HSL (G) were cultured in flow cells for 6 days. P. aeruginosa cells carried the gfp plasmid pMRP9-1. Squares are 30 μm on a side.