This sounds a little like multi-crystal averaging without the averaging.
If you were using the Uppsala program suite, you could perhaps do the
following:
[define one xtal as reference, the other as target]
1. Make mask in map grid for reference xtal (program MAMA)
2. Establish operator for reference -> target transformation
e.g. from protein superimposition with LSQMAN
3. Improve this operator for the two density maps (program MAVE)
* do not average the maps, which would otherwise be the usual step
4. Expand the reference map into the target xtal, by lying to MAVE that
the reference map is the averaged map. (program MAVE)
There also appears to be an "EZ skewing" option in MAVE.
Make sure you make the mask around the unknown density large enough so
that MAVE/Improve has some density to work with for optimization that
isn't just the unknown blob. You could always use a larger mask for
this step and a smaller one for the MAVE/Expand step.
Phil Jeffrey
Princeton
Rana Refaey wrote:
Hi,
I have two maps from two different crystals with the same space group, both
show an unknown density in the same place. I wanted to superimpose the maps
to see if it is the same/similar density.
Any ideas how to do this ?
Thank you,
Regards
Rana
