Maybe a bit of an obvious suggestion but....
Vector-derived seqeunce?
What is there between your tag or cleavage site, assuming you have one?
HTH,
Dave
On 26/09/06, Dominique Monferrer Ventura <[EMAIL PROTECTED]> wrote:
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Dear all,
I am at the stage of refinement of a structure and there is extra positive
electron density at the N-terminii of both chains which I don't know how to
explain. I have 1M mercaptoethanol in the buffer, and 2M sodium formate in
the crystallization condition. The unexplained blob fits quite well with
mercaptoethanol, but I wonder if this compound could have reacted with the
methionines of the N-terminus? What about the formate?
Thankyou for any suggestions,
Dominique
--
Dominique Monferrer
Departament de Biologia Estructural
Institut de Biologia Molecular (CSIC)
c/Jordi Girona 18
Barcelona 08034
ESPANYA
Tel. +34 93 400 61 00
[EMAIL PROTECTED]
--
---------------------------------------
David Briggs, PhD.
Father & Crystallographer
www.dbriggs.talktalk.net
