Dear CCP4BBers, I am trying to crystallize a protein-protein complex with Kd in the range of ~40uM. I think that if I hike the concentration of the complex by 10-fold(~400uM), I would still have ~25%of uncomplexed material present. Is it possible that I add some crowding agent such as PEG to bring down the Kd value? Any suggestions or strategies would be very helpful.
Thanks, Amit
