FIG. 2.

Dependence of tagD transcription on RNA polymerase binding before PhoP∼P. Reactions as described for Fig. 1 except that the order of component addition was different and some reaction mixtures were preincubated. DNA, tagD template (Fig. 1B); P, PhoP; R, PhoR; RNAP, purified B. subtilis RNA polymerase. −, absent; +, present; ↓, preincubation at 37°C for 10 min. A, DNA template; B, mixture of PhoP, PhoR, and ATP; C, RNA polymerase. The order of component addition is indicated proceeding from top to bottom above lanes 3 to 5.