raffaele at gracco.irmkant.rm.cnr.it Wed Jun 8 14:06:11 EDT 1994
>Do anyone know how to calculate the coordinates of the atoms of
>the backbone from phi and psi angles?
>We got a short C program that calculates phi-psi angles from
>Brookhaven protein data files but we need to do the reverse:
>we are trying to simulate the folding process and we need to
>model how changing the phi-psi angles affect the protein shape.
>thanks in advance
>Centro Chimica del Farmaco
>e-mail: raffaele at gracco.irmkant.rm.cnr.it
Sucessive coordinates of the backbone atoms (N,C-alfa,C-pri) are generated
using starting set of coordinates of three atoms. The fourth atom is generated
when its geometry is known, using the analytical calculation of atomic coords.
(Ramachandran and Sasisekharan, Adv.Prot.Chem., 1968,vol.23, p.283.
I have the program in Fortran and I can help you with this if you need.