Could this be a metal cluster? Is your protein solution colored at all? Have
you made an anomalous difference map? Is there reductant in the mix? What
small molecules were in the mother liquor?
JPK
----- Original Message -----
From: "<Justyna Wojdyla>" <[email protected]>
To: <[email protected]>
Sent: Thursday, August 12, 2010 10:24 AM
Subject: [ccp4bb] Unidentified density.
Dear All,
I am refining structure of protein at 1.7A. It is enzyme with 3 histidine
residues in the active site, which are chelating metal (at the moment I
built in calcium but I do not know for sure, which metal is bound there).
I can see additional density "on top" of metal, which I can not identify:
http://picasaweb.google.com/j.a.wojdyla/Density#
None of the crystallization or protein buffer's components could fit
there and it seems to be something picked up during expression.
I would be very grateful for any suggestions.
Thank you in advance.
Justyna
*******************************************
Jacob Pearson Keller
Northwestern University
Medical Scientist Training Program
Dallos Laboratory
F. Searle 1-240
2240 Campus Drive
Evanston IL 60208
lab: 847.491.2438
cel: 773.608.9185
email: [email protected]
*******************************************
