Bernhard Rupp wrote:
> Dear All,
>
> I wonder about the exact use of torsion restrains and the effect
> on phi/psi/w validation.
>
----
>
> a) does refmac restrain phipsi at all (except vdw repulsion
> which does not bias them otherwise)?
>
Isn't it the case that vdw interactions are turned off
between atoms in a residue, and perhaps with the residues
before and after?
Otherwise positional refinement would in fact tend to drive
the residues into the rama-allowed region?
Might it be a good idea to use torsion restraints, or
intra-residue vdw repulsion, in the last stage of refinement
after calculating an unbiased ramachandran plot;
especially in low-resolution problems where we need all the
restraints we can get?
Ed
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