Re: [ccp4bb] Map averaging question

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Map averaging question
From: Simon Kolstoe s {- dot -} kolstoe {- at -} UCL {- dot -} AC {- dot -} UK
Date: 2009-12-04

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Subject: Re: Map averaging question
From: Kevin Cowtan cowtan {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-12-04

Subject: Re: Map averaging question
From: Vellieux Frederic Frederic {- dot -} Vellieux {- at -} IBS {- dot -} FR
Date: 2009-12-04

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.

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Map averaging question
From: Simon Kolstoe s {- dot -} kolstoe {- at -} UCL {- dot -} AC {- dot -} UK
Date: 2009-12-04

Next message:
Subject: Re: Map averaging question
From: Kevin Cowtan cowtan {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-12-04