dppA, a negative target of GcvB, is subject to sRNA competition. Isogenic strains carrying a PBAD–dppA–lacZ fusion were used to observe sRNA competition, as for Fig. 4. Cells were grown and assayed as for Fig. 6, but 0.0005% arabinose was used to induce the fusion; for each strain, the basal activity was that seen with the plac control plasmid.
A. WT (KM 86); basal activity was 74 units.
B. ΔgcvB (KM339); basal activity was 116 units.