Re: [ccp4bb] Two Equally Good MR Solutions Found by Phaser

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: NADP - ADP binding
From: Paul Smith paul {- at -} PALADINSCIENTIFIC {- dot -} COM
Date: 2009-10-20

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From: Artem Evdokimov artem {- at -} XTALS {- dot -} ORG
Date: 2009-10-20

Subject: Re: Two Equally Good MR Solutions Found by Phaser
From: "X Xiong, Cellular & Molecular Medicine" x {- dot -} l {- dot -} xiong {- at -} BRISTOL {- dot -} AC {- dot -} UK
Date: 2009-10-20

Hi,

Thanks for all the replies. Paul said the two solutions are the same by
crystallographical symmetry, does that mean the origin of the unit cell has
changed and P21212 can have arbitrary origin of the cell along the b-axis?
As I have generated the symmetry related pairs from each solution in Coot,
they do not overlap each other but partly clashed into each other along the
b-axis. Another question is I thought Phaser can automatically prune the
solutions that are cryptographically the same (as suggested in its log file
), did Phaser fail that in my case?

For the comments on incompleteness at low resolution, I thought it was
crystal mounting problem, there was no overloads as crystal is tiny and
diffracted weakly, but it is very strange that two of the axes are very
incomplete at low resolution, I don't know any explanation for that, and
due to the incompleteness at low res, systematic absences can not be
observed, so space group can not determined by looking at them.

Thank for all the advices so far, and I would like more suggestions to
clarify my doubts.

cheers

----------------------
Xiaoli Xiong
PhD Candidate
Department of Cellular and Molecular Medicine
School of Medical Sciences
University of Bristol
University Walk
Bristol BS8 1TD, UK
x.l.xiong@bristol.ac.uk

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: NADP - ADP binding
From: Paul Smith paul {- at -} PALADINSCIENTIFIC {- dot -} COM
Date: 2009-10-20

Next message:
Subject: Colored proteins :)
From: Artem Evdokimov artem {- at -} XTALS {- dot -} ORG
Date: 2009-10-20