Re: [ccp4bb] how to run detwin?

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

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Subject: Re: how to run detwin?
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-08-03

I guess someone has answered this?

Q1 Before detwinning data you must process in the lower symmetry..

Comment.
It may not bre necessary or sensible to use detwin - the resukltant
estimates of I are pretty unreliable..
You can use twinned data usually to solve an MR problem, and the
refinement programs cope with twinning well enough now.
From REFFMAC the output MTZ file actually contains Fobs(detwinned) and
Fcalc for the untwinned structure.

(The Fobs(detwinned) is confusingly still LABELLED FP! - this will be
changed asap)

Eleanor

Laurie Betts wrote:
> I have a P62 crystal that is probably p31 (or P32). When I run the
> detwin program to actually output detwinned data,
> do I input the mtz as processed (e.g. as output from dtrek or HKL2000)
> in the wrong (higher symmetry) or
> the correct space group - Thanks
>
>
>
>
> Laurie Betts
> University of Pittsburgh
> X-ray Crystallography Facility Manager
> Department of Structural Biology
> 3501 Fifth Avenue,
> Pittsburgh, PA 15260
> 412-383-5839
> lab117@pitt.edu
>
>

CCP4bb navigation

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

Previous message:
Subject: Rfree going up
From: kumar bputcha {- at -} UTK {- dot -} EDU
Date: 2009-08-01

Next message:
Subject: Re: maprot question
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-08-03