This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
User:Tilman Schirmer/Sandbox 100
From Proteopedia
(→Repetitive torsion angles) |
(→Repetitive torsion angles) |
||
| Line 40: | Line 40: | ||
phi-psi = (-50<sup>o</sup>, -26<sup>o</sup>), '''3<sub>10</sub> helix''': | phi-psi = (-50<sup>o</sup>, -26<sup>o</sup>), '''3<sub>10</sub> helix''': | ||
<scene name='User:Tilman_Schirmer/Sandbox_100/310helix/1'>model</scene>, | <scene name='User:Tilman_Schirmer/Sandbox_100/310helix/1'>model</scene>, | ||
| - | <scene name='User:Tilman_Schirmer/Sandbox_100/310helix/2'>Calpha-trace</scene> <br> | + | <scene name='User:Tilman_Schirmer/Sandbox_100/310helix/2'>Calpha-trace</scene> <br><br><br><br><br><br> |
==== α-Helix ==== | ==== α-Helix ==== | ||
Revision as of 23:35, 19 March 2009
Contents |
Secondary structure of proteins
Repetitive torsion angles
|
A polypeptide chain with a repetition of identical phi-psi torsion angles yields a helical structure.
phi-psi = (180o, 180o), fully extended chain:
,
phi-psi = (-140o, 130o), extended chain:
,
; this is the β-strand conformation found in beta-sheets
Note:
polypeptide forms a with side-chains protruding towards alternating (up, down) directions
the polypeptide main-chain is as can been seen when looking along the chain
phi-psi = (70o, 180o):
,
; note that there are clashes (where?)
phi-psi = (-60o, -40o), α-helix:
,
phi-psi = (-50o, -26o), 310 helix:
,
