Figure 2.

BglG directly interacts with RNAP. Purified MBP–BglG (lanes 1) or MBP (lanes 2) was incubated with purified RNAP and antibodies against RNAP holoenzyme (A) or against MBP (B), both raised in rabbit. Immunoprecipitated proteins were fractionated by using SDS/PAGE, blotted onto nitrocellulose filters, and probed with antibodies against MBP (A) or against RNAP holoenzyme (B). The filter was reacted with a secondary antibody, goat-anti rabbit, which was detected as described in Material and Methods. The first antibody, which is included in each incubation, also fluoresces up because of the interaction with the secondary antibody. Lane M contains RNAP as a marker.