[ccp4bb] Restraints in Refmac5

2008-06-26 Thread yael_benhar
Hi everyone,

I am refining a protein structure containing a Beryllium Fluoride (BeF3) 
ligand.  I am using Refmac5 in ccp4i.  
The distances between the Be and the F atoms  are slightly longer than what I 
would expect (1.7A instead of ~1.5A).

Does anyone know how I can fix the distances and restrain the bond lengths for 
the BeF.

Thanks,

Yael.


Re: [ccp4bb] Restraints in Refmac5

2008-06-26 Thread Partha Chakrabarti
One question is, why do you want to fix that and from what literature
are you expecting the values?

BeF3- is often a ground state analogue for GTP binding proteins for
example.. and the depending on the coordination state, the bond angle
and length might change a bit I would have thought.. for example, if
you have an oxygen from a ligand and a water close enough to the Be,
then the bond order of the B-F is lower.. if you have good resolution,
this might be interesting in the other way around..

Cheers, Partha




On Thu, Jun 26, 2008 at 3:26 PM,  [EMAIL PROTECTED] wrote:
 Hi everyone,
 I am refining a protein structure containing a Beryllium Fluoride (BeF3)
 ligand.  I am using Refmac5 in ccp4i.
 The distances between the Be and the F atoms  are slightly longer than what
 I would expect (1.7A instead of ~1.5A).
 Does anyone know how I can fix the distances and restrain the bond lengths
 for the BeF.
 Thanks,
 Yael.



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