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[ccp4bb]: pi-cation interaction in Refmac

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Thank you all for the suggestions about my question (below) related to
pi-cation interactions in Refmac.
	In summary I got two different suggestions:

	1) To turn off van der waals interactions for the nitrogen atom
	of the ligand.
	In PROTIN this can be done using the keyword VDWRADII

	2) fix distances for all pi-cation interactions. 
	In PROTIN this can be done using the keyword SPECIAL. 


	> Dear CCP4bb members
>         I am refining a protein-ligand complex where the main
> interactions
> between those are hydrophobic and a cation-pi interaction between a
> nitrogen and a Phe ring.
>         I used MAKEDICT to create a dictionary for my ligand, but
> because of
> the cation-pi interaction, REFMAC pushes protein and ligand apart.
>         Is there any way to turn off the energy terms only for my 
> ligand or it would be better to add the cation-pi interaction into the
> dictionary, if so, how do I do that?
>         Thanks all
>         Cristy
>         *******************************
>         Maria Cristina Nonato, PhD
>         Chemistry and Chemical Biology
>         Cornell University
>         mcn22@cornell.edu
>         phone:+1.607.255.6145
>         *******************************