FIG 5.

VpsR binds specifically at the tfoY promoter region. (A) Images show polyacrylamide gels from electrophoretic mobility shift assays (EMSAs). The probes were end labeled with fluorescein and detected with a Typhoon imager. The specific tfoY promoter region used in each probe is indicated in Fig. S5. The positive-control probe contains sequence from a region of the vpsT promoter to which VpsR was previously shown to bind. The lanes for each blot from left to right are 0, 25, 120, 360, and 650 nM VpsR. (B) The sequence encoded in the P₃ binding site deletion probe was constructed as a transcriptional gfp fusion and analyzed for induction by overexpression of the DGC QrgB or its active-site mutant QrgB*. conc., concentration.