I have just come back from a meeting where the following problem reared
its ugly head
MOLREP was used to test a set of SGs and found a good solution in one of
them; P2 21 2 for example.
But the refinement against the original data stuck.. The explanation is
this:
Although the MOLREP wrote out the correct SG to the coordinates, the mtz
file still had the first guess at SG - in this case P222
The current version of REFMAC DOES NOT COMPLAIN if there is disagreement
between the 2 SG provided from the data and the coordinates, and tried
to carry out the refinement in the mtz SG.
The solution is a) use phaser which gives a correct SG in its
associated mtz.
b) use a tools such as
mtzutils hklin1 P222.mtz hklout P2212.mtz
SYMM P2212
But be careful!
Eleanor
Kay Diederichs wrote:
> Jacob,
>
> you could use, for refinement, the FP SIGFP columns from the .mtz-file
> that PHASER writes out, together with the .pdb-file of the best solution.
>
> One caveat: the resolution of the data in that file is what you chose
> for the PHASER calculation, so you might need to re-run PHASER with
> the full resolution (no need to do the full calculation again, there
> are shortcuts possible using the "known solution").
>
> HTH,
>
> Kay
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