AMBER Archive (2000)

Subject: Re: perturbing charge

From: Bill Ross (ross_at_cgl.ucsf.edu)
Date: Fri Sep 29 2000 - 18:55:00 CDT


        I have a DNA molecule with several Adenine. I would like
        to perturb the charge in one of them. I am using xleap to first select
        that particular Adenine and then perturb the charge. If I do it this way,
        will the charges on the other Adenine also get perturbed? Do I have to
        define a different residue first?

As long as you select the atom from the dna strand, the perturbation
will only affect that atom. Conversely, the way to perturb all such
atoms in all such residues would be to perturb the residue model
(e.g. DA) before doing a loadpdb. Then the model gets copied for
each residue in the pdb file. Once it's copied, it is unique as
far as further changes go, like adding perturbation.

Bill Ross