Re: [ccp4bb] how to decrease Rfac and Rfree

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

Previous message:
Subject: Fwd: summer internship in structural biology
From: Artem Evdokimov artem {- at -} XTALS {- dot -} ORG
Date: 2009-12-28

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Subject: Re: how to decrease Rfac and Rfree
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-12-29

Subject: Re: how to decrease Rfac and Rfree
From: Kay Diederichs kay {- dot -} diederichs {- at -} UNI-KONSTANZ {- dot -} DE
Date: 2009-12-29

RONG hui Rong schrieb:
> Dear all,
>
> I am solving a structure containing 2 heterodimers in one ASM. First, got
> the solution by MR( 11-3.6Ã…, modified model template with Rfac and Rfree 47%
> and 48%,respectively). After some model building by hand in terms of
> 2mFo-DFc map bearing 0.41 for Rfac and 0.42 for Rfree, except molecule 1,2
> and 3 fitting the 2mFo-DFc map well , the 4th molecule presenting poor,
> however, the 4th molecule fit the mFo map well( of course, another 3 mols
> fit well). After model building by hand based on the mFo map coupled with a
> cycle of simulating and minimizing, it produced poor maps (2mFo-DFc as well
> as mFo, almost main chain broken, disorderly) for mol 4 except molecule 1,2
> and 3 fitting the 2mFo-DFc as well as mFo map well and just a little
> decreasing on Rfac and Rfree.
>
> How can I do? Can anybody give me some inspiration?
> Many Thanks!
>
> SCL
>

Dear RONG hui Rong,

some inspiration can hopefully be obtained from the CCP4 wiki, in
particular see
http://strucbio.biologie.uni-konstanz.de/ccp4wiki/index.php/Refinement
and the web services collected at
http://strucbio.biologie.uni-konstanz.de/ccp4wiki/index.php/Crystallography#Web_services

HTH,

Kay
--
Kay Diederichs http://strucbio.biologie.uni-konstanz.de
email: Kay.Diederichs@uni-konstanz.de Tel +49 7531 88 4049 Fax 3183
Fachbereich Biologie, Universitaet Konstanz, Box M647, D-78457 Konstanz

CCP4bb navigation

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

Previous message:
Subject: Fwd: summer internship in structural biology
From: Artem Evdokimov artem {- at -} XTALS {- dot -} ORG
Date: 2009-12-28

Next message:
Subject: Re: how to decrease Rfac and Rfree
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-12-29