Purify a His Tag protein for Crystallization

[mrsankar_in at yahoo.co.uk]

Hi all,

I have a His Tag protein overexpressed in E.coli and it does not go into inclusion bodies. I want to crystallize the protein for which i need it in a very high concentration and in very pure form. What way i can purify the protein in Ni Column? Denaturing or native conditions?

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