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
