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[ccp4bb] b-factors from refmac tls refinement vs cns mlf refinement
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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999
Previous message:
Subject: EM maps in phaser
From: Cynthia Czyrphony cynthia {- dot -} czyrphony {- at -} GMAIL {- dot -} COM
Date: 2007-06-13		Next message:
Subject: Screening, ADMET workshop, wiki activity on method evaluation, validation, international cooperation
From: barry {- dot -} hardy {- at -} TELE2 {- dot -} CH barry {- dot -} hardy {- at -} TELE2 {- dot -} CH
Date: 2007-06-13


Subject: b-factors from refmac tls refinement vs cns mlf refinement
From: CRAIG MCELROY mcelroy {- dot -} 31 {- at -} OSU {- dot -} EDU
Date: 2007-06-13

Hi all,
I'm working on the structure of a heterodimer phased by molecular replacement using data to 2.9 angstroms. After MR I performed a rigid body refinement in CNS, if I then refine using mlf in CNS I get B-factors ranging from ~37-119 and r= 0.26 free_r= 0.35 whereas if I perform a TLS restrained refinement in refmac (with each monomer of the heterodimer as a TLS group or with one of the monomers divided into two TLS groups based on tlsmd) I get B-factors ranging from ~2-48 and r= 0.22 free_r= 0.28. Based on the R values it certainly seems like the TLS refinement is better, but the B-factors from the TLS refinement seem artificially low and the ones from CNS seem too high. The maps from the TLS refinement also look much better with less breaks in the density and less difference density. I'm wondering if this is typical and what I should do to diagnose/fix the problem.
Thanks
Craig

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999
Previous message:
Subject: EM maps in phaser
From: Cynthia Czyrphony cynthia {- dot -} czyrphony {- at -} GMAIL {- dot -} COM
Date: 2007-06-13		Next message:
Subject: Screening, ADMET workshop, wiki activity on method evaluation, validation, international cooperation
From: barry {- dot -} hardy {- at -} TELE2 {- dot -} CH barry {- dot -} hardy {- at -} TELE2 {- dot -} CH
Date: 2007-06-13
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