GST fusion protein

[Luc CAMOIN]

Dear netters,

I expressed a fusion protein produced in E Coli. The fusion protein is a
GST tagged protein and the predicted molecular weight is around 45 kDa. My
protein of interest is a very hydrophobic protein of 19 kDa.
Purification on Glutathione sepharose 4B and western blot with anti GST
revealed only a band around 25 kDa. This molecular weight and reactivity
with anti GST could suggest that this protein is GST alone.
Can we conclude that the contact between GST and the protein of interest is
a protease sensitive region? Is this a known problem? Did you also find
this problem in your experiments? Can you give me references about this
problem?

Thanks in advance,


Luc CAMOIN





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