Wong,
did you look for pseudo-symmetry? For example for pseudo-translation,
which you can deduce from a native Patterson.
Good luck,
Klaus
Mo Wong wrote:
> Hello,
>
> My problem: I have poorly phased 3.5A data which suggests 6 molecules per
> ASU, and using MolRep with the experimental phases ("search for model in the
> map") I have good solutions 3 of them. There is a lot of empty electron
> density which needs to be filled with more copies of the molecule. I have
> looked for NCS operators as I know this will improve the map and help with
> model fitting (the Self Rot function suggests I have at least 2-fold
> symmetry), but no luck yet. My current focus is on using the 3-molecule
> partial solution as a starting point, but since I'm not getting anywhere
> fast, I though I'd post to the bulletin board.
>
> Can someone please either point me to a MolRep script that allows me to fix
> the known solutions, use the experimental phases, and search for (3?) more
> copies of the model, or tell if there is something wrong with the following
> Phaser scripts below (....is it necessary to apply an operator to the MolRep
> solution before reading into Phaser?).
>
> Thanks!
>
> #####
> phaser << eof
>
> MODE MR_FRF
>
> HKLIN overall_best_denmod_map_coeffs.mtz
> LABIN F = FP SIGF = SIGFP
>
> ENSEMBLE trimer PDBFILE trimer.pdb IDENTITY 0.25
> ENSEMBLE monomer PDBFILE monomer.pdb IDENTITY 0.25
> COMPOSITION PROTEIN SEQUENCE trimer.seq NUM 1
> COMPOSITION PROTEIN SEQUENCE monomer.seq NUM 3
>
> SOLU 6DIM ENSE trimer EULER 0 0 0 FRAC 0 0 0
>
> SEARCH ENSEMBLE monomer NUM 1
>
> ROOT AUTO_monomer
>
> eof
> #####
> phaser << eof
>
> MODE MR_FTF
>
> HKLIN overall_best_denmod_map_coeffs.mtz
> LABIN F = FP SIGF = SIGFP
>
> ENSEMBLE trimer PDBFILE trimer.pdb IDENTITY 0.25
> ENSEMBLE monomer PDBFILE monomer.pdb IDENTITY 0.25
> COMPOSITION PROTEIN SEQUENCE trimer.seq NUM 1
> COMPOSITION PROTEIN SEQUENCE monomer.seq NUM 3
>
> @AUTO_monomer.rlist
>
> ROOT AUTO_monomer2
>
> eof
> #####
>
>
--
Dr. Klaus Piontek
Albert-Ludwigs-University Freiburg
Institute of Organic Chemistry and Biochemistry, Room 401 H
Albertstrasse 21
D-79104 Freiburg
Germany
Phone: ++49-761-203-6036
Fax: ++49-761-203-8714
Email: [log in to unmask]
Web: http://www.chemie.uni-freiburg.de/orgbio/w3platt/
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