Dear all,
I have two low resolution (3.8 A) MAD data sets from two different
space groups. There are 4 copies of my molecule in one space group
and 2 copies in the other. The density-modified maps from these data
sets are poor, but still allow me to build a crude model on them.
All the domains should be at the right or close to right orientations
and positions. I would like to try multi-crystal averaging to
improve my maps. Since I already have the model, I used NCSMASK to
make 6 masks for the 6 copies of my model. Then I used DMMULTI to
perform the multi-crystal averaging. The maps came out of DMMULTI
showed great improvement. Some densities were not seen before showed
up nicely. However, after I read the manual carefully, I realize
that DMMULTI would not take care of the mask overlap. So some
regions in my density map between the NCS-related and symmetry-
related molecules must be messed up. Could any expert out there
give me some suggestions about how to make proper NCS masks for
DMMULTI? Thanks at advance.
Jianghai
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