[modeller_usage] upper and lower distance restraints

[Youbin Tu <>]

Hi all:

   I want to define some restraints in the top file. Assume we know the 
maximum and minimum distances between two atoms (non-bond), Which form 
and group type should we use? since there are so many types of groups 
to define distance restraints, which one should I use for my case? I 
looked through the manual, but did not find enough talking about it. 

   Here is an example, 
                The maximum distance between Fe:513 and C7:514 is 
6.0(1.0)
                The miminum distance between Fe:513 and C7:514 is 
2.0(1.0)
   I included the following line in the top file:

SUBROUTINE ROUTINE = 'special_restraints'
   ADD_RESTRAINT ATOM_IDS =  'FE:513' 'C7:514', ;
   RESTRAINT_PARAMETERS = 2 1 1 22 2 2 0 6.0 1.0

   ADD_RESTRAINT ATOM_IDS =  'FE:513' 'C7:514', ;
   RESTRAINT_PARAMETERS = 1 1 1 21 2 2 0 2.0 1.0
 
  RETURN
END_SUBROUTINE

    Is it correct?

   Again, If I did so, does that mean that the program have to force 
the 
distance between those 2 atoms within that range even though it may 
take the risk to corrupt the whole structure? Or if some restraints 
will destroy the whole structure, the program will discard the user's 
restraints in order to " save" the final model? 
   thanks.
                                                                   
youbin

----------------------
Youbin Tu
CCMM Lab,BPS
Schoof of Pharmacy,WVU