FIGURE 3.
Fractional occupancies of YvrI and YvrHa of B. subtilis in EC on PyvrI promoter. A, representative data assessing the components of RPo and EC. Same as described in the legend to Fig. 2A but with the PyvrI promoter. B, fractional occupancy of YvrI and YvrHa with respect to the RNAP core: determined by quantifying the amount of each protein from gel. Data were the average of six replicates. Gray bar, YvrI; black bar, YvrHa. C, representative data for the in vitro transcription assay with RPo immobilized on streptavidin beads. Stalled elongation complexes EC+10 and EC+19 were generated using 32P-labeled NTP; chase, all four NTP were added to EC to produce runoff products. The samples were run on 12% urea PAGE and scanned on a phosphorimager. D, fractional occupancies of YvrI and YvrHa after correction for the subpopulations that are competent to form EC. Data were average of six replicates. Gray bar, YvrI; black bar, YvrHa.