FIGURE 8.
Specific bindings of IscR, CRP, and SmcR to PgbpA. A 390-bp DNA fragment of the gbpA regulatory region was radioactively labeled and then used as a probe DNA. The radiolabeled probe DNA (5 nm) was mixed with increasing amounts IscR (A), CRP (B), and SmcR (C) as indicated. For competition analysis, the same but unlabeled 390-bp DNA fragment was used as a self-competitor DNA. Various amounts of the self-competitor DNA were added to a reaction mixture containing the 5 nm labeled DNA prior to the addition of 30 nm IscR (A), 30 nm CRP (B), and 100 nm SmcR (C). B, bound DNA; F, free DNA.