PDB file modification using specific dihedral backbone angles phi and psi

Question

[epsilone]

Short version: I am trying to modify a PDB file so that it has a particular set of backbone angles phi and psi. Is there any library or software that performs such a task?

A little more explained: I know how to obtain the phi and psi dihedral angles from a PDB file, there are several tools for that purpose, and I am currently using bio3d package in R. I want to modify slightly the backbone angles and then be able to obtain the PDB file whose backbone is defined by the modified angles. Do you know how to perform this?

Thanks in advance!

[ballisticws]

Not sure I understand completely, but maybe you could try TINKER's protein tool, http://dasher.wustl.edu/tinker/

I know you can build the structure from sequence using psi/phi angles, alone.