Re: [ccp4bb] Problems in MR

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CCP4bb <-- 2007 <-- March 2007 <-- 05 March 2007

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Subject: Re: CNS v1.2 and unwanted introduction of OXT
From: "Fred {- dot -} Vellieux" vellieux {- at -} IBS {- dot -} FR
Date: 2007-03-05

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Subject: Re: CNS v1.2 and unwanted introduction of OXT
From: "Fred {- dot -} Vellieux" vellieux {- at -} IBS {- dot -} FR
Date: 2007-03-05

Subject: Re: Problems in MR
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2007-03-05

You dont say the spacegroup. Different MR solutions can exist relative
to any of the acceptable alternate origins.
Eg If it were P21 say the two solutions could lie anywhere along the b axis.

Try running superpose (coordinate utility ) matching sequences. If the
rotation looks like a symmetry operator then that is probably what has
happened..

Re the refinement - that is another more difficult problem at 3A with
37% sequence ID...
Eleanor

thunderbird wrote:
> Hi all.
> I am trying to solve a structure with one molecules in the asu through MR.
> Using a not good data set at 3.0A and a structure with sequence similarity of
> 37%, Phaser gave a result of z score 14.7 and LL-gain 220, probably a right
> solution.
> But when I slightly modified the model I got from Phaser and used it as an
> input to run Phaser again, I got another solution overlapped partly with the
> first solution. I don't know how it could happen like that. And the Rfree
> factor could not go
> below 0.43 in the following refinemet. I am wondering what is wrong with it?
> thanx in advance
> Lei Yin
>
>
> Lei Yin, Ph.D.
> National Laboratory of Biomacromolecules
> Institute of Biophysics
> Chinese Academy of Sciences
> No. 15 Datun Road, Beijing 100101, China
> E-mail:thunderbird@moon.ibp.ac.cn
> Tel: 86-10-64888548
>
>
>

CCP4bb navigation

CCP4bb <-- 2007 <-- March 2007 <-- 05 March 2007

Previous message:
Subject: Re: CNS v1.2 and unwanted introduction of OXT
From: "Fred {- dot -} Vellieux" vellieux {- at -} IBS {- dot -} FR
Date: 2007-03-05

Next message:
Subject: Re: CNS v1.2 and unwanted introduction of OXT
From: "Fred {- dot -} Vellieux" vellieux {- at -} IBS {- dot -} FR
Date: 2007-03-05