-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Hello Misbah Ghafoor <Misbah.Ghafoor at postgrad.manchester.ac.uk> wrote:
> I am working on the NMR structure determination of a small molecule
> which has a two-fold symmetry. I have tried running the small molecule
> structure determination script povided by Xplor, however it doesnt
> seem to work for my symmetrtic molecule. I obtain no overlays at all
> after my refinement steps. I would like to mention I did use NOE and
> dihedral angle constraints for EVERY part of the molecule (including
> both symmetrical parts).
You need noncrystallographic and distance symmetry restraints. Assuming
the two dimer subunits are in segids A and B, you can apply these
restraints by adding the snippet below to your python script.
best regards--
Charles
# ``NCS'' term - keep dimer subunits identical
from posDiffPotTools import create_PosDiffPot
ncs = create_PosDiffPot("ncs","segid A","segid B")
ncs.setScale(1000)
potList.append( ncs )
# distance symmetry
#
from distSymmTools import create_DistSymmPot, genDimerRestraints
from selectTools import minResid, maxResid
dSymm = create_DistSymmPot('dSymm')
for r in genDimerRestraints(segids=['A','B'],
resids=range(minResid(),maxResid(),10)):
dSymm.addRestraint(r)
pass
dSymm.setShowAllRestraints(True)
dSymm.setScale(100)
potList.append(dSymm)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)
Comment: Processed by Mailcrypt 3.5.8+ <http://mailcrypt.sourceforge.net/>
iEYEARECAAYFAkpA7gwACgkQPK2zrJwS/laR0QCfcv3M2T9KF9vQMtNnPF0URF7G
grgAn0MRE0K7tMUKNxYfMmFNB6fi76O5
=MOqA
-----END PGP SIGNATURE-----
