Re: [ccp4bb] High overall b-factor

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

Previous message:
Subject: Re: questions related to refmac refinement and map-fitting
From: David Schwefel rock34 {- at -} GMX {- dot -} NET
Date: 2007-03-19

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From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2007-03-19

Subject: Re: High overall b-factor
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2007-03-19

There have been other discussions of this. In fact if the data peters
out at 3.2A I think you would expect such a high B.
But also it is quite difficult to estimate the overall B for such a data
set - look at the Wilson plot from the Importscaled data step and see
what value it suggests?

Eleanor

George Lountos wrote:
>
> Hello all:
>
> I just recently collected data on initial crystals I grew of an enzyme
> with inhibitor. The crystals diffract to only 3.2 A but I was able to
> get phases by molecular replacement to see if there is any inhibitor
> bound. Although the data processed well in HKL2000 with good
> statistics and the current structure refinement is at R-factor of 22%
> and R-free 30% at 3.2 A, the overall B-factor of the protein is very,
> high (100 A^2). I can see difference density for the ligand in the
> active site and after refinement it fits well in the density but the
> B-factor for the ligand is 110. I have not come across a refinement
> with such high B-factors where the protein density and ligand density
> can be distinguished at such high B-factors. Does anyone have any
> suggestions if there is something going wrong here?
>
> Thanks,
>
> George
>
>
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CCP4bb navigation

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

Previous message:
Subject: Re: questions related to refmac refinement and map-fitting
From: David Schwefel rock34 {- at -} GMX {- dot -} NET
Date: 2007-03-19

Next message:
Subject: Re: Differences in R and Rfree
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2007-03-19