Re: [ccp4bb] Lower completeness, decent R factors, but low B factor...

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

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From: "Winter, G (Graeme)" g {- dot -} winter {- at -} DL {- dot -} AC {- dot -} UK
Date: 2008-08-20

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Subject: Re: Lower completeness, decent R factors, but low B factor...
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2008-08-20

James Pauff wrote:
> Hello all,
>
> I have a refined structure at 2.6 angstroms that at about 73% completeness at this resolution. The I/sigma is about 2.0 at 2.6 angstroms, and the omit density for my ligands is great contoured at 3.0sigma. My Rcryst is 19 or so and the Rfree is 24.5 or so.
>
> HOWEVER, my mean B value is 13.9, whereas my other 2 structures (at 2.2 and 2.3 angstroms, same protein, >95% completeness) have mean B values of 22+. Any suggestions as to what is going on here? I'm having trouble explaining this.
>
> Thank you,
> Jim
>
>
>
>
>
>
Have you used TLS - listed B factors will then be given relative to the
TLS parameters. You need to run tLSANL to get a more realistic value.
Eleanor

But in fact temperature factors are rather harder to estimate at lower
resolutions than higher. Look at your and curves v resolution
( part of a REFMAC loggraph) and you can see that sometimes the overall
scaling struggles to get a reasonable fit..

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

Previous message:
Subject: Coot and OS X Leopard
From: "Winter, G (Graeme)" g {- dot -} winter {- at -} DL {- dot -} AC {- dot -} UK
Date: 2008-08-20