XPLO2D from the USF-Suite does this:
<snippet from manual>
You feed it a PDB file of the model to which you want to restrain your
refinement model (e.g., that high-resolution native structure you
already have, even though it may be in a different spacegroup or with
different domain orientations). The program generates an X-PLOR include
file which contains DIHEdral statements for the PHI, PSI, CHI-1 and
CHI-2 torsions of the protein. If you protein contains a hinge region,
simply remove or comment-out the relevant PHI and PSI restraints. If you
don't want to impose restraints on CHI-1 and/or CHI-2, set the
corresponding weights to zero (at the top of the X-PLOR include file).
I never tried, but this will be compatible with phenix as well.
Cheers
Eckhard
Phil Evans schrieb:
Does anyone have a good way of imposing secondary structure restraints
in a low resolution refinement?
I've done this in the past as hydrogen bond distance restraints within
helices, input to refmac as "LINK"s , with the list generated with a
little program and certain amount of pain
refmac now accepts an explicit list of external restraints, as does
phenix.refine, but I'm looking for a way of generating these lists for
quite a large structure without too much hackery, perhaps from a
hydrogen-bond or secondary structure assignment program. Helices are
reasonably straightforward (I can see how to do them from eg DSSP), but
sheets are more complicated.
Any suggestions? I'm sure that someone must have done this
Phil
--
Eckhard Hofmann <eckhard.hofm...@bph.ruhr-uni-bochum.de>
Ruhr-Uni Bochum
AG Proteinkristallographie, LS Biophysik, ND04/316
44780 Bochum
Tel: +49-(0)234/32-24463, Sekr. -24461, FAX: -14762