Hello All, I apologize for the non-crystal related question. I am trying to get a fully metal-free apo enzyme. The 6x His construct is consistently purified with some metal (20-30%). I have attempted chelating away the metal with up to 30 mM EDTA and DFO and then dialyzing it away, but this has shown little to no effect. Any thoughts or recommendations would be greatly appreciated. Thanks.
Adam
