Hi Fellows,

 

something that may eventually become an issue for validation and reporting
in PDB headers:

 

using the Refmac grouped occupancy keyword I was able to form and refine
various networks of correlated 

alternate conformations - it seems to works really well at least in a 1.6
and 1.2 A case I tried.

Both occupancy and B-factors refine to reasonable values as expected/guessed
from e-density and environment.

Respect & thanks for implementing this probably underutilized secret.

 

This opens a question for validation: Instead of pretty much ignoring any
atoms below occupancy of 1, one 

can now validate each of the network groups' geometry and density fit
separately just as any other

set of coordinates. I think with increasing data quality, resolution, and
user education such refinements will become more

frequent (and make a lot more sense than arbitrarily setting guessed
independent hard occupancies/Bs

that are not validated). Maybe some common format for (annotating) such
correlated occupancy groups might 

eventually become necessary.

 

Best, BR

 

PS: Simple example shown below: two alternate confs of residue 338 which
correlate with one 

water atom each in chain B, with corresponding partial occupancy (grp1:
A338A-B5 ~0.6, grp2: A338B-B16 ~0.4).

 

occupancy group id 1 chain A residue 338 alt A

occupancy group id 1 chain B residue 5

occupancy group id 2 chain A residue 338 alt B

occupancy group id 2 chain B residue 16

occupancy group alts complete 1 2

. more similar.

occupancy refine

 

AfaIct this does what I want. True?

 

----------------------------------------------------------------------------
------------

Bernhard Rupp 

k.-k. Hofkristallamt

001 (925) 209-7429

 <mailto:b...@ruppweb.org> b...@ruppweb.org

 <mailto:b...@hofkristallamt.org> b...@hofkristallamt.org

 <http://www.ruppweb.org/> http://www.ruppweb.org/

-----------------------------------------------------------------------

 

 

Reply via email to