3 10 -Helix

from Wikipedia, the free encyclopedia
Difference between Alpha-Helix and 3 10 -Helix in the top view : Alpha-Helix more square top view, 3 10 -Helix more triangular top view

The 3 10 -helix (3.0 amino acids per 360 ° rotation, 10-membered ring of hydrogen bonds) is a secondary structure motif of peptides and proteins that can occur at the ends of α-helices and also separately and about 10% of the helix part of globular proteins. It is a right-handed helix with about three amino acid side chains per revolution. The 3 10 -helix is stabilized by intramolecular C = O ••• HN hydrogen bonds between the nth and the (n + 3) th amino acid. This hydrogen bond creates a ring with ten bonds, which corresponds to the structure of a β-turn of subtype III. The van der Waals contacts and hydrogen bonds are not as optimal in proteins as those of the α-helix, so that often only short 3 10 helices with two to three hydrogen bonds occur.

literature

  • Jeremy M. Berg, John L. Tymoczko, Lubert Stryer : Biochemistry. 6 edition, Spektrum Akademischer Verlag, Heidelberg 2007. ISBN 978-3-8274-1800-5 .
  • Donald Voet, Judith G. Voet: Biochemistry. 3rd edition, John Wiley & Sons, New York 2004. ISBN 0-471-19350-X .
  • Bruce Alberts , Alexander Johnson, Peter Walter, Julian Lewis, Martin Raff, Keith Roberts: Molecular Biology of the Cell , 5th Edition, Taylor & Francis 2007, ISBN 978-0-8153-4106-2 .