Hi Alexei,
at this resolution you most likely need to refine isotropic group B (one
B per residue or so) or/and do TLS refinement (on top of it).
Cheers,
Pavel.
---
Pavel V. Afonine, Ph.D.
Lawrence Berkeley National Lab, Berkeley CA, USA (http://www.lbl.gov/)
CCI: Computational Crystallography Initiative (http://cci.lbl.gov/)
PHENIX (http://phenix-online.org/)
On 3/26/2008 10:49 AM, Alexei Datsuk wrote:
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
