Paul will have to answer re 20 NCS operators in coot..
But you dont need to generate the operators yourself.
If you have a master coordinate set with all 20 copies you can use coot
to build one into the average map, then generate all the others by
asking to match chain A to B, A to C etc.. within coot.
Dont forget tpo relabel the chains after shifting the rebuilt one!
Eleanor
Vellieux Frederic wrote:
Simon Kolstoe wrote:
Hi,
I have 20 identical monomers in my asu of a 2.5A structure. We have
previously model built all twenty monomers and used strict NCS in the
refinement, however I would like to compare this with the maps
generated by building one monomer into an averaged map and then
replicating it nineteen times for the refinement. On a previous
structure with just two monomers I did this to good effect using coot
to make my average map and then pymol to replicate the second monomer,
however with twenty monomers things are a bit more complicated. So:
1. Can the map averaging function in coot cope with averaging across
twenty monomers or is there another better program to use?
2. What program can I use to generate the nineteen NCS symmetry
operators and then apply them to the monomer I am building? I’m
guessing I’ll need a script to do this - is there a webpage/tutorial
that explains how to do what I imagine must be a fairly common procedure?
Thanks,
Simon
Hi Simon,
NCS symmetry operators:
It all depends on the averaging program you want to use. For dm, I've
used superpose (in ccp4i). For DEMON/ANGEL, I use the program SUPPOS
(provides matrices and vectors in the correct format).
Fred.
