Fig. 5. CytR titration in the absence (left panel) and presence (middle and right panels) of cAMP–CRP. The right panel is in the presence of 20 mM cytidine in addition to cAMP–CRP. The concentration of CytR in each lane for all three panels was as follows: 0, 5, 10, 15 and 20 nM from left to right. (A) The transcription products were resolved in denaturing 8% polyacrylamide gel. (B) deoP2 RNAs were quantified with a β-scanner and the total c.p.m. were plotted as a function of CytR concentration.