Extended Data Fig. 7: High concentrations of ppGpp slow-down the ‘fast’ H526Y RNAP in vitro.
a, In vitro transcription reactions of E. coli RifR rpoB H526Y RNAP with increasing concentrations of ppGpp (0,0.1 and 1 mM). At the highest ppGpp concentration, reactions were performed with or without DksA. Stalled RNAP elongation complexes (20-mer, denoted with the red arrow) were chased to the end of the template (runoff, denoted with the blue arrow), and the labelled nascent RNA then separated using PAGE. For in vitro transcription experiments, n = 3 independent replicates. b, Quantification plot of signal from gel scans as a function of distance from the initial site of stalling (right-end on the x-axis). Arrows (labelled 1 through 6) correspond to major pause sites.
