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Re: [ccp4bb] How to refine large moleculars?
 

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CCP4bb <-- 2008 <-- January 2008 <-- 08 January 2008
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Subject: Re: How to refine large moleculars?
From: Lari Lehtio lari {- dot -} lehtio {- at -} KI {- dot -} SE
Date: 2008-01-08
Without knowing the resolution, you could try to use TLS refinement (if you haven't done it
already) and see if the maps improve and allow you to build more/better. If the resolution is
reasonable and you can not lower the R & Rfree you should check whether twinning is
possible. It is common AFAIK that in twin cases the R-factors get stuck above 30 %.

~L~

_______________________________________

Lari Lehtiö
Structural Genomics Consortium
Medical Biochemistry & Biophysics Dept.
Karolinska Institute
Stockholm, Sweden
_______________________________________

----- Original Message -----
From: Yongchao Li
Date: Tuesday, January 8, 2008 1:51 am
Subject: [ccp4bb] How to refine large moleculars?
To: CCP4BB@JISCMAIL.AC.UK

> I have a large molecule to refine.There are about three thousand
> residues in one asymmetric unit.
> Except for the lack of electron densities in several places, where
> the
> loops have been deleted, the rest parts fits well with density. But
> the R free and R work are all beyond 0.30 (R free = 0.35, R work =
> 0.30).I don't know how to reduce them.
> Can anyone give me some ideas?
>
> Thank you!
>
>
>
> ---------------------------------
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