Frances
It looks like the 3-fold is combining with dyads to make a pseudo 432
arrangement. If you're of space group and that there is only one trimer in
asymmetric unit, look internal structural similarity within a monomer. For
instance, multiple similarly folded domains.
Doug Ohlendorf
-----Original Message-----
From: CCP4 bulletin board [mailto:[log in to unmask]] On Behalf Of
Francis E Reyes
Sent: Thursday, March 18, 2010 10:03 AM
To: [log in to unmask]
Subject: [ccp4bb] self rotation education
Hi all
I have a solved structure that crystallizes as a trimer to a reasonable
R/Rfree, but I'm trying to rationalize the peaks in my self rotation. The
space group is P212121, calculating my self rotations from 50-3A,
integration radius of 22 (the radius of my molecule is about 44). I can see
the three fold NCS from my structure on the 120 slice, but I'm trying to
rationalize apparent two folds in my kappa=180. A picture of both slices is
enclosed. The non crystallographic peaks for kappa=180, P222 begin to appear
at kappa=150 and are strongest on the 180 slice.
My molecule looks close to a bagel (44A wide and 28A tall). The three fold
NCS is down the axis of looking down on the bagel hole. I'm trying to find
the two fold. I imagine it could be slicing the bagel in half (like to eat
it for yourself) or slicing it vertically (like to share amongst kids) but
I'm not exactly sure what's the best way to visualize this. Is there
something easier than correlation maps with getax (since I have the rotation
(polarrfn) and translation?). If you have an eye for spotting symmetry, Ill
send the pdb in confidence.
Thanks!
FR
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