Re: [ccp4bb] Bad r factor at low resolution

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

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Subject: Bad r factor at low resolution
From: Armando Albert de la Cruz xalbert {- at -} IQFR {- dot -} CSIC {- dot -} ES
Date: 2009-10-16

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Subject: Re: Bad r factor at low resolution
From: Pavel Afonine PAfonine {- at -} LBL {- dot -} GOV
Date: 2009-10-16

Hi Armando,

high R-factor at low resolution is likely to be due to poor bulk solvent
model. Some relevant reading:

Jiang, J.-S. & Brunger, A. T. (1994). J. Mol. Biol. 243, 100-115.
"Protein hydration observed by X-ray diffraction. Solvation properties
of penicillopepsin and neuraminidase crystal structures."

A. Fokine & A. Urzhumtsev. Acta Cryst. (2002). D58, 1387-1392. "Flat
bulk-solvent model: obtaining optimal parameters"

P.V. Afonine, R.W. Grosse-Kunstleve & P.D. Adams. Acta Cryst. (2005).
D61, 850-855. "A robust bulk-solvent correction and anisotropic scaling
procedure"

Pavel.

On 10/16/09 7:55 AM, Armando Albert de la Cruz wrote:
> What does it mean having the R factors a high resolution lower than at
> low resolution?. Could be related to the fact my model is incomplete?
> Armando

CCP4bb navigation

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

Previous message:
Subject: Bad r factor at low resolution
From: Armando Albert de la Cruz xalbert {- at -} IQFR {- dot -} CSIC {- dot -} ES
Date: 2009-10-16

Next message:
Subject: Re: DMMULTI question
From: Pete Meyer pameyer {- at -} MCW {- dot -} EDU
Date: 2009-10-16