[ccp4bb]: CCP4 : Space group transformations

[David A R Sanders <dars@st-andrews.ac.uk>]

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I have a sorta double-barrelled/loaded question. I'm working on a protein
that we have managed to collected data for in 2 different space-groups.
We have very shoddy phasing inforation for one of the space-groups and
were hoping to be able to do cross-crystal averaging (using DM-Multi) on
both the forms as this will greatly improve our phases.

It appears that the two cells are related :

#1 P2(1) - unit cell :  a, b, c   - the b axis is very close to 90
degrees
#2 P2(1)2(1)2(1) - unit cell (relating to #1) :  b, c, 2a

We figure that the transformation involves a 1/4 shift along one of the
axis, but aren't positive which one or if more is needed as well..

The second question is that having figured out the transformation, how do
you fool AMORE into doing a transformation search only along the one axis
necessary ??

Many thanks,

	David

*************************************************************
* David Sanders, Ph.D.                                      *
* Structural Biology Division                               *
* School of Biomedical Sciences                             *
* University of St. Andrew's, UK                            *
* dars@st-andrews.ac.uk                                     *
* http://speedy.st-and.ac.uk/~davids                        *
*************************************************************