Fig. 4.

Like rpoS, crc dampens phenazine-supported metabolic activity but contributes to phenazine resistance. (A) SRS images of thin sections prepared from WT, Δcrc, and ΔcrcΔphz biofilms. SRS signal is false-colored yellow and the average signal across depth is shown in the right-hand plot (Scale bar, 50 µm). (B) Left: Scheme depicting experimental design. Right: Growth of WT, ΔrpoS, and Δcrc on 1% tryptone, 1% agar medium without or with 800 µM PMS. For (A) and (B), experiments were performed with biological triplicates and representative data are shown. (C) Top: Scheme depicting experimental design. Bottom: Quantification of colony-forming units from 3-d-old biofilms, displayed as a percentage of the WT value. Each point represents a biological replicate. P values were calculated using unpaired, two-tailed t tests (***P < 0.001 and ****P < 0.0001).