FIG 6.

Model for the role of Anr in lasR mutant biofilms. In the presence of LasR-mediated QS (A and B), Anr is active in biofilms and is required for production of CupA fimbriae, but absence of Anr does not affect HAQ production, H2-type VI secretion, or expression of the operons PA5232-PA5230 (containing a putative collagenase gene) and PA3913-PA3911 (encoding a putative ABC transporter). In the absence of lasR signaling (C and D), increased Anr activity leads to increased production of CupA fimbriae, and Anr is required for HHQ/HQNO production and H2-type VI secretion, as well as expression of the operons described above.