[ccp4bb]: Re:

["Eleanor J. Dodson" <ccp4@ysbl.york.ac.uk>]

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N. Gautham wrote:
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> 
> Hello all,
> 
>   This is a general MR question. Can some one enlighten me on the
> relationship, if any, between the resolution of the data and the
> accuracy of the model used in MR. For example, if I use only low
> resolution data say 6.0 A to calculate the rotn. fn., etc, can I get
> results by using a model that has rmsd of say 6.0 A from the 'true'
> structure? Any references, comments would be welcome. Thanks.
> 
> Gautham
> 
As far as I know there is no known case of MR solution at any resolution 
from a coordinate model with rmsd of 6A.
But there are cases where EM maps have been fitted successfully against 
Xray data..

However low homology models work better with lower resolution data, but 
I tend to use cut offs of 2.5A for a near perfect model, and 4A for a 
low homology one..

At 6A there may well be other problems - results can be influenced by % 
of solvent, crystal symmetry, etc etc etc..

Eleanor