Re: "reasonable Phi/Psi angles?

Markus Jaritz (markus@Irina.came.sbg.ac.at)
Mon, 13 Mar 1995 17:38:02 +0100 (MET)

On Mon, 13 Mar 1995, Stephen Tate wrote:

> Hi,
> =09Can somebody tell me what a reasonable Phi/Psi angle is in a helix or =
a sheet
> ?
>=20
> Thanks=20

Hi Steve !

The best way to find out is to take a look at the so-called
"Ramachandram-Plot" which you may find in biochemical
secondary literature.

In this plot, the Phi angles are plotted against the Psi angles.
Regions are marked for "reasonable" (allowed) angle combinations=20
for *all* residues, and the regions often found in helix and sheets
are quite well visible.

It would not be natural science, if there would be no exception for
some special residues, Prolin and Glycin for example. The first
shows a more restricted area, the second can be found in much more
conformational states, owing to the loss of a side-chain.

Tsch=FCs, Markus.
=20