FIG. 4.

DNase I footprinting analysis of IHF binding to the glt DNA. DNA fragments extending from −176 to +8 of the template strand (the strand complementary to the mRNA sequence) (A) or from −203 to +161 of the nontemplate strand (B) of the gltBDF operon were footprinted in the presence of 0 to 100 nM IHF. Dideoxy sequencing reactions of the gltBDF promoter region with the primer glt2 (for the template strand) and gltFP (for the nontemplate strand) were used to generate the ladders. IHF protected the region (shown in brackets) from −113 to −76 on the template strand and the region from −115 to −75 on the nontemplate strand against DNase I digestion. The positions of the sequences are given with respect to the transcription start site.