Separating GST from GST-fusion protein

[Peter Ellis]

On Thu, 16 Apr 2009, Pow Joshi wrote:
>
> ah, only if it is absolutely imperative that you have a pure protein,
> and have some time at hand: perhaps you could generate polyclonals
> against the whole mixture of gst+ gst-protein; then drain out the gst
> antibodies against a gst column.... once that is done, and you are
> left with the antibodies against your protein, which you can then use
> to affinity purify your fusion .... Gee, but I guess it's far too
> involved anyways .... perhaps Dima's and Wo's ideas are better to try
> first....

It looks as though the converse might make more sense.  If there's an 
antibody available that recognises free GST but not a GST fusion, you 
could use that to remove the free GST from your mix.  Unfortunately I 
don't know if any such antibody exists!  Would be nice if there is one, 
since it's a general solution to the problem and should work no matter 
what fusion partner you're working with.

Peter