Thanks Eleanor, your tip has got me there. I was attempting the problem
the wrong way round.
To get it to work
I had to reindex the P212121 h=-l k=k l=h
Then rigid body refinement of the P213 symmetry generated trimer dropped
it to 40% and NCS refinement to around 25%
My reasoning for avoiding doing it this way round is that presumably if
we deposit the P213 and the P212121 structures the wwPDB will reset to
a<b<c (I seem to remember)
A quick go at trying to reverse this has not worked. Maybe the radius
of convergence of a rigid body is lower in the higher symmetry space
group??
For info
In P213 a=b=c 75.953
P212121 a=74.504 b=77.473 c=79.894
The SSM fit is 0.79 over virtually all Calphas for the symmetry
generated trimer in P213 onto the P212121 structure
In response to Herman
The final P213 data set is actually higher resolution (we have collected
several of these at a range of resolution as we improved cryo/crystal
size/sampled more crystals/cooling pathways). The P212121 was the
highest at one point and has better density for some loops.
Many thanks to all who sent me hints
Nick
--
Prof Nicholas H. Keep
Executive Dean of School of Science
Professor of Biomolecular Science
Crystallography, Institute for Structural and Molecular Biology,
Department of Biological Sciences
Birkbeck, University of London,
Malet Street,
Bloomsbury
LONDON
WC1E 7HX
email n.k...@mail.cryst.bbk.ac.uk
Telephone 020-7631-6852 (Room G54a Office)
020-7631-6800 (Department Office)
Fax 020-7631-6803
If you want to access me in person you have to come to the
crystallography entrance
and ring me or the department office from the internal phone by the door
