Re: REFMAC/PROTIN & NCS

["Eleanor J. Dodson" <ccp4@yorvic.york.ac.uk>]

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Joao Alexandre R. G. Barbosa wrote:
> 
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> Dear all,
> 
> In PROTIN, one can use NONX to especify NCS restraints, while in REFMAC, there
> is the NCSR option. I have refined a structure following the example 6, step 2
> in the EXAMPLES section of the REFMAC manual. The example only uses NONX in
> PROTIN. Is this sufficient for REFMAC to undertake a NCS restrained
> refinement, or do I need to use the NCSR option in REFMAC?
> 



 THe NCSR key word in Refmac is only to reset the relative weighting for
"tight" "medium" and "loose" restaints for both coordinates and b
factors. 

 I have forgotten the defaults but "loose" is very loose indeed and if
need be you can make it even looser.

 The idea would be perhaps to have those residues in a seperate "span"
so that yuou can preserve medium side chain restraints where
appropriate.

 Eleanor Dodson