Fig 5.

EMSA of His₆-CcpA with the promoters of the gal operon (A) and manL (B). DNA fragments of the gal operon promoter carrying intact cre (gal-p) (lanes 1 to 10) or without cre (gal-p-cre) (lanes 11 to 15) and the manL coding region (manL in) (lanes 16 to 20) and promoter (manL-p) (lanes 21 to 30) were PCR amplified and end labeled with biotin. The added CcpA concentrations are indicated above the lanes. Lanes 7 to 10 (A) and lanes 26 to 30 (B) contain the same amount (100 nM) of CcpA, but with increasing concentrations (2, 10, 20, and 40 nM) of unlabeled gal promoter fragment (Ngal-p) or manL promoter fragment (NmanL-p), respectively, as a competing substrate for CcpA. The black arrows indicate the shifted migration positions of the CcpA-bound promoter fragment, the gray arrows indicate the free DNA fragments, and the open arrow (A) indicates the negative-control DNA (com box).