FIG. 6.

Effects of PCA (A), ATP (B), ADP (C), and AMP (D) on the binding affinity of PcaO for its target sequence. PCA was not included in the experiments whose results are shown in panels B to D. In all experiments, the PcaO concentration was 0.5 μM and the concentration of the ³²P-labeled pcaHG promoter sequence was 1 nM.