On 09/30/2011 08:01 AM, Yuri Pompeu wrote:
> Hello everyone,
> I am refining a structure to 2.4A with 2-fold NCS and twinned.
> Maps look ok and Rfree is 0.27however as I start checking my validations I notice that after refinemnt
> my geomtry gets significantly worse. especially the rama plot. Initially I have 2 outliers and I end up with 32 (5%)!!!
> I played with the Xray weight term but alll it helped me with was rmsd bond/angles, rama is still messing up...
> Can I impose some ramachadran restraints or maybe have a reference model?
>
> best,
Dont foreget the usual reason for Rama outliers is model error! Check
c=O are correct - cis peptides correctly defined in PDB ( coot and
REFMAC USED to get these knotted.. ) etc etc..
Eleanor
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