Help: GST-protein cleaved.

[D.K.]

In article <20030407203914.6267.qmail at ww02.hostica.com>, hyi at ksu.edu wrote:
>
>I am expressing a GST-protein (vector=pGEX-2T, host=BL-21), but the product is
> cleaved so I have two populations of expressed protein. Can anybody tell me
> how to solve this problem ? Thank you very much.

Nothing except the generic advice is possible: 

1) Find out if the cleavage is in vivo or in vitro. If it vitro, use 
proper protease inhibitors to suppress. If in vivo then 
2) change host and or/vector/fusion partner and see how you fair. 
3) If everything else fails, purify one from another using either
i) conventional approaches or ii) by introducing second tag 
on C-terminus.

DK