thanks, how can I flip a selection of atoms around an arbitrary axis?

2010/6/28 Edward A. Berry <>
Jakob Nielsen wrote:
> Dear Pymol users,
> I would like to modify a protein pdb file with a "crankshaft" flip,
> which is the anti-correlated double change: psi(i-1) += delta and phi(i)
> -= delta. Such a change should leave the protein coordinates unchanged
> effecting only atoms in residues i-1 and i. However implementation in
> pymol (see below) changes the coordinates of _all_ residues from i-1 to
> the C-terminal.

I think this is expected because in general psi(i-1) and phi(i)
will be rotating about different axes. You might try flipping
the residue itself about an axis passing through its N and O atoms,
followed by some regularization to fix the geometry.


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