Re: [ccp4bb] Help with pseudosymmetry problem

[Derek Logan]

Hi Peter,

Can you try to run xtriage and see what it tells you in terms of
possible twin laws and merging statistics in higher symmetry space
groups?

The log file is attached. xtriage does not find any clear signs of pseudosymmetry or higher metric symmetry, but it does detect the pseudo-translation peak at (0.129, 0.475, 0.218) with 10% of the origin height, which it doesn't consider as significant (I get 20% when I do it using FFT)

If for some reason no twin laws are found, you can manually change the
unit cell on the command line to have beta exactly equal to 90...

I didn't do this, as possible twin law was found. Or have I misunderstood the logic?

Let me know what the logfile tells you. If the translation is
'special' xtraige will tell you what the approximate pseudo symmetry
would be.

It doesn't seem to think so.

Derek

P.S. Great program by the way!

xtriage.log
Description: Binary data

2008/4/23, Derek Logan <[EMAIL PROTECTED]>:

Hi everyone,


kappa=180° section of the SRF, calculated using Molrep, is at

http://mole.mbfys.lu.se/~derek/selfRF_180.png


these in the list of peaks from Molrep:

           theta    phi     chi    alpha    beta   gamma     Isym_i
Isym_j



it's not there. I'm sure I'm missing something fundamental about the

to bug about this (I *am* the supervisor...)

In the native Patterson

http://mole.mbfys.lu.se/~derek/nativePatterson.png


and have weak internal symmetry. I believe this was an issue with the

and structure article I wasn't able to find a rationalisation of this

peaks?

Thanks
Derek

Can anyone help me with interpretation of a self rotation function and native Patterson from a dataset with pseudosymmetry? I've always been a bit poor on spherical polars. The space group is P21 with beta = 92.2°. The and contains two big peaks around 7 sigma. I'm having trouble identifying Sol_RF 1 0.00 0.00 0.00 0.00 0.00 0.00 1 1 Sol_RF 1 90.00 -90.00 180.00 0.00 180.00 0.00 1 2 Sol_RF 1 90.00 90.00 180.00 0.00 180.00 0.00 2 1 Sol_RF 1 0.00 0.00 0.00 0.00 0.00 0.00 2 2 Sol_RF 2 158.56 180.00 180.00 0.00 42.89 -180.00 1 1 Sol_RF 2 111.44 0.00 180.00 -180.00 137.11 0.00 1 2 Sol_RF 2 111.44 0.00 180.00 180.00 137.11 0.00 2 1 Sol_RF 2 21.44 0.00 180.00 180.00 -42.89 0.00 2 2 Sol_RF 3 165.65 0.00 180.00 -180.00 28.70 0.00 1 1 Sol_RF 3 104.35 -180.00 180.00 0.00 151.30 180.00 1 2 Sol_RF 3 104.35 180.00 180.00 0.00 151.30 -180.00 2 1 Sol_RF 3 14.35 -180.00 180.00 0.00 -28.70 180.00 2 2 It seems to me to be two copies of peak 2. I believe theta starts in the middle, perpendicular to the page and phi starts on the x axis, thus the peak just below the centre would be (21.44, 0, 180). I presume that the second peak is the symmetry-related (158.56, 180, 0)? However where is (111.44 0 180)? I would expect to see this near the bottom of the plot, but symmetry of the SRF projection, but unfortunately I don't have a supervisor there are two peaks of almost equal height. How can this be reconciled with having only one strong peak in the SRF? There are most likely two dimers in the asymmetric unit, but there may only be one, with very high resulting solvent content. What's more the molecules are leucine-rich repeat proteins ribonuclease inhibitor, but looking briefly at the crystallisation article problem. The 2-fold is perpendicular to b*. How could this cause the two

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