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Re: [ccp4bb] b-factors from refmac tls refinement vs cns mlf refinement |
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CCP4bb navigationCCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999Subject: Re: b-factors from refmac tls refinement vs cns mlf refinement From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK Date: 2007-06-13 These are B factors RELATIVE to your TLS parameters. You need to run tlsanl to get back to something comparable to the individual B factors.. Eleanor CRAIG MCELROY wrote: > 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 navigationCCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999 |
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