FIGURE 8.

Stability of the protein-effector bond. (a) In the presence of C₇-HL, no binding is observed. (b) After the sample was washed multiple times with buffer solution over the course of 1 h and C₁₂-HL was added, the protein-DNA complex is still inactive. The reverse process was investigated with a new tip and sample surface: (c) In the presence of C₁₂-HL, the protein-DNA complex shows its usual degree of activity. (d) C₇-HL was added after the sample was washed multiple times over the course of 1 h. Activity is only slightly reduced. Obviously, C₇-HL is not able to displace C₁₂. Both experiments indicate a high stability of the protein-effector bond.