> I had a simple question about DNA binding protein. Is there an
> easy way to detect if your heterologously expressed protein is bound to
> DNA post purification.
Yes. UV absorbance. DNA absorbs UV strongly, proteins do not. DNA absorbs
260 more thn 280, the opposite is true for proteins. In fact, it's always a
good idea to check 260/280 ratio because quite frequently even non-DNA
binding proteins purified by a single tag affinity chromatography contain
enough DNA to skew estimation of protein concentration from 280 nm
absorbance by several fold (9X in one case of my personal experience).
>Also is there an easy way to strip the protein of DNA without any damage
>done to the protein in doing so.
No generic solution. Greatly depends on the protein and its properties.
Dima
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