Figure 3.

Inhibition of transcription from amyE and veg promoter by CcpA. Run-off transcriptions were carried out by using the linearized plasmids containing the veg promoter (veg), the amyE promoter (amyE), and a mixture of the two plasmids (veg + amyE) in the absence (C) and presence of various concentrations of CcpA (28–560 nM; veg and amyE, 28–780 nM; veg + amyE). The veg promoter was used as a negative control to test specific inhibition of transcription by CcpA. Two transcripts from the amyE-promoter region, 126 nt (1) and 112 nt (2), and a transcript from the veg promoter, 95 nt (3), are labeled on the Right. The shortest transcript (4) detected at both plasmids was produced from a promoter in the common portion of the two plasmids.