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Re: [ccp4bb] Question about strange MR solution
 

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CCP4bb <-- 2008 <-- February 2008 <-- 04 February 2008
Previous message:
Subject: Question about strange MR solution
From: Michele Lunelli efunit {- at -} YAHOO {- dot -} IT
Date: 2008-02-04 		Next message:
Subject: His tag
From: Yanming Zhang yzhang {- at -} MAILER {- dot -} SB {- dot -} FSU {- dot -} EDU
Date: 2008-02-04


Subject: Re: Question about strange MR solution
From: Marius Schmidt marius {- dot -} schmidt {- at -} PH {- dot -} TUM {- dot -} DE
Date: 2008-02-04
Dear Michelle,
this is not strange at all. You simply have
a MR solution that refers to a different origin.
You cannot display the original model plus the
MR solution in the same coordinate system (with
respect to the same origin). Of
course they clash.

Greetings
Marius

> Dear all,
>
> I refined a protein structure in the space group P6(1)22, with one
> copy in the
> asymmetric unit, resolution ~1.8 A, Rwork=0.20, Rfree=0.22.
> Then I tried to feed Phaser (version 1.3.3) with this structure. It
> found
> quickly a very prominent solution, but the first euler angle is 180
> instead of 0
> degrees (the others are 0, as well as the fractional coordinates).
> This solution
> is not symmetry-related with the structure that I used as search
> model: indeed,
> there are a lot of clashes. However, when I refine this solution, I
> obtain
> immediately R factors as good as the search model, and also the
> electron density
> map looks perfect. Of course, I used the same reflections file to
> refine the
> initial structure and the MR solution rotated of 180 degrees.
>
> How can I explain this? The analysis with Truncate (moments and
> cumulative
> intensity distribution) don't suggest any twinning, as well as the
> Padilla-Yeates test. Is it possible, that I refined the structure in
> the wrong
> space group?
>
> Thank you in advance,
>
> Michele Lunelli

CCP4bb navigation

CCP4bb <-- 2008 <-- February 2008 <-- 04 February 2008
Previous message:
Subject: Question about strange MR solution
From: Michele Lunelli efunit {- at -} YAHOO {- dot -} IT
Date: 2008-02-04 		Next message:
Subject: His tag
From: Yanming Zhang yzhang {- at -} MAILER {- dot -} SB {- dot -} FSU {- dot -} EDU
Date: 2008-02-04


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