Dear All, Recently I am working on a protein-DNA complex, and from running agarose gel, there is a weak delayed band after the band of pure DNA which indicates some DNA has bind to the protein though the binding efficiency is low. Then I tried to optimize the condition to increase the binding, but it did not work since the intensity of the delayed band didnot grow. The condition I used is list below: 1. the concentration of protein is about 1.5mg/ml, buffer in Tris-Cl, PH 8 and NaCl. 2. the running buffer for agarose gel is 0.5x TBE, PH 8.3. 3. different ratio of protein: DNA has tried, from 2:1 to 1:2. 4. different concentration of NaCl, MgCl2 and ATP in reaction system have been added, but no significant change.
I wonder if there is any way to increase the binding efficiency? Is it possible to set up crystal plates in this situation, with protein and complex together? Any suggestion would be appreciated! Best Yang