Sequence between the −10 and −35 regions of the nap promoter confers phenazine sensitivity. (A) Schematics of promoter-gfp fusion reporter constructs. napEp, promoter of the nap operon; TSS, transcription start site; RBS, ribosome-binding site. Orange, yellow, and green boxes indicate regions of the promoter sequences being shuffled. Expression reported by promoter-gfp fusions of truncated (B) and shuffled (C) nap promoter sequences in WT and Δphz backgrounds. Strains were grown in shaken liquid culture (MOPS plus 20 mM glucose plus 20% LB medium). Error bars represent standard deviations from biological triplicates. (D) Graphical representation of the sigma factor RpoS and sequence elements conferring redox sensitivity.