FIG. 6.
Effect of 3-phosphoglycerate and phosphoenolpyruvate on the pattern of DNase I protection caused by CbbRII binding to the cbbII promoter. The phosphorimage of a DNase I footprint of CbbRI binding to a cbbII promoter probe fragment alone (A) and in the presence of 1 mM phosphoenolpyruvate (PEP) (B) or 1 mM 3-phosphoglycerate (PGA) (C). The probe is labeled on the top strand and spans nucleotides −151 to +46 relative to the cbbF transcription start. Brackets indicate regions of protection, and asterisks indicate DNase I hypersensitive sites. The concentration of CbbRII in each reaction is indicated above each lane. A standard lane containing a Maxim-Gilbert A+G sequencing ladder of the probe is also shown.