Hello James,
my first guess would be a second conformation. If the cysteine is part
of a disulfide bridge, it could be a partially broken bridge due to
radiation damage, and the "extra atom" would be the sulfhydryl group
in VdW distance to the former partner cysteine.
Best regards,
Dirk.
Am 21.04.2009 um 11:39 schrieb James Stroud:
Hello All,
I have a couple of cysteines with some extra density about 1
covalent bond's length away from the sulfur center. It looks to be
one atom's worth of extra density. Because I could fit it in an icon
sized graphic and I anticipate that someone will suggest I post a
picture, I'm attaching a picture of the positive fofc density.
Does anyone have any idea of the usual culprits here? I see no
negative density in the region.
James
<greencys.png>
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Dirk Kostrewa
Gene Center, A 5.07
Ludwig-Maximilians-University
Feodor-Lynen-Str. 25
81377 Munich
Germany
Phone: +49-89-2180-76845
Fax: +49-89-2180-76999
E-mail: kostr...@lmb.uni-muenchen.de
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