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User:Tilman Schirmer/Sandbox 100
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(Difference between revisions)
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A polypeptide chain with a repetition of identical phi-psi torsion angles yields a helical structure. | A polypeptide chain with a repetition of identical phi-psi torsion angles yields a helical structure. | ||
| - | Examples: | + | <blockquote>Examples: |
fully extended chain: phi-psi = (180, 180), model, Cα-trace | fully extended chain: phi-psi = (180, 180), model, Cα-trace | ||
extended chain: phi-psi = (-140, 130), model, Cα-trace; this is the beta-strand conformation found in beta-sheets | extended chain: phi-psi = (-140, 130), model, Cα-trace; this is the beta-strand conformation found in beta-sheets | ||
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phi-psi = (-50, -26), model, Cα-trace; this is the conformation of a 3<sub>10</sub> helix | phi-psi = (-50, -26), model, Cα-trace; this is the conformation of a 3<sub>10</sub> helix | ||
| + | </blockquote> | ||
| + | ==== α-Helix ==== | ||
| - | ==== a-Helix ==== | ||
| - | + | ==== β-sheet ==== | |
| - | ==== | + | |
Revision as of 12:31, 15 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.
Examples: fully extended chain: phi-psi = (180, 180), model, Cα-trace extended chain: phi-psi = (-140, 130), model, Cα-trace; this is the beta-strand conformation found in beta-sheets phi-psi = (70o, -180), model, Cα-trace; note the severe clashes phi-psi = (-60, -40), model, Cα-trace; this is the alpha-helical conformation phi-psi = (-50, -26), model, Cα-trace; this is the conformation of a 310 helix
