[ccp4bb] TLS refinement at low resolution

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Subject: Protein Crystallography Postdoctoral Position Available
From: Carolyn Cohen ccohen {- at -} BRANDEIS {- dot -} EDU
Date: 2008-03-26

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Subject: Re: TLS refinement at low resolution
From: Pavel Afonine pafonine {- at -} LBL {- dot -} GOV
Date: 2008-03-26

Subject: TLS refinement at low resolution
From: Alexei Datsuk alexeidatsuk {- at -} GMAIL {- dot -} COM
Date: 2008-03-26

Hi,

I have a question with B-factor and TLS refinement. My protein diffracts
only to modest/low resolutions (3.4 A). I've been refining isotropic
B-factors for main chain and side chain (not individual atoms) because I'm
worried at this resolution I don't have enough observations to justify
individual B-factor refinement.

First question: Is this a good assumption on my part, or should I try
refining individual B-factors and look at how R/Rfree behaves? I just don't
want to be over-refining my structure.

Second question: Can I do TLS refinement at low resolution when B-factors
are only refined for main chain and side chain? I would imagine that I need
to be refining individual B-factors.

Third question: Is it justified for me to be doing TLS refinement at these
resolutions?

Thanks

Alexei

CCP4bb navigation

CCP4bb <-- 2008 <-- March 2008 <-- 26 March 2008

Previous message:
Subject: Protein Crystallography Postdoctoral Position Available
From: Carolyn Cohen ccohen {- at -} BRANDEIS {- dot -} EDU
Date: 2008-03-26

Next message:
Subject: Re: TLS refinement at low resolution
From: Pavel Afonine pafonine {- at -} LBL {- dot -} GOV
Date: 2008-03-26