Re: [ccp4bb]: Protein crystals with a 10 His tag?

[Tim Grüne <grune@embl-grenoble.fr>]

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I work on a protein that crystallises with the His-tag cut off
(the pProEx-Ht[a-c] vectors from Lifetechnologies come with a 6xHis-tag
and a Tev cleavage site), but not with the His tag left on. As far as I
know, His-tags are believed to be unstructured and flexible, i.e., they
inhibit crystallisation. Therefore, the shorter the better, but this must
not always be true. The charged tag may as well positively alter your
proteins behaviour.
Tim

 On Fri, 30 Nov 2001,
Narayanan Manoj wrote:

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>
> Dear all,
>            I am trying to crystallize a protein with a 10 His tag. I
> would like to know of any experience with a successful crystallization.
> Is a 6 His tag better than a 10 His tag or is it best to have no His tag
> at all?
> many thanks in advance
> manoj
>
>
>
>

-- 
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Tim Gruene, grune@embl-grenoble.fr
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