Re: [ccp4bb] r-factor does not reduce

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

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Subject: Re: r-factor does not reduce
From: Roger Rowlett rrowlett {- at -} COLGATE {- dot -} EDU
Date: 2009-09-10

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Subject: Re: r-factor does not reduce
From: Ezra Peisach epeisach {- at -} GMAIL {- dot -} COM
Date: 2009-09-10

On 09/10/2009 12:17 PM, Sean Seaver wrote:
> Hello Sylvia,
>
> Two issues I would consider:
> 1) recheck the space group
> 2) make sure that I had selected a good model for my MR search
>
> All the Best,
>
> Sean
>
Hi Sylvia,

If you have just used rigid body refinement - the Rfactor might be high
until you have allowed the individual atoms to move.

You did not indicate the resolution you are using - but every crystal is
slightly different and parts of your model will likely need to move
some. The higher the resolution - the larger the effects of slightly
incorrect positions will be.

The best criteria would be to look at the electron density maps and
evaluate what you see. Is there good backbone connectivity? Do you see
improvements to make in the model? Is there difference in sequence that
is clearly shown - say a small sidechain changed to something large and
bulky? If so - you probably have the correct MR solution...

Ezra

CCP4bb navigation

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

Previous message:
Subject: Re: r-factor does not reduce
From: Roger Rowlett rrowlett {- at -} COLGATE {- dot -} EDU
Date: 2009-09-10

Next message:
Subject: non-CCP4 related: HKL2MAP availabilty
From: Ajit Datta adatta4 {- at -} JHMI {- dot -} EDU
Date: 2009-09-10