π helix

The π-helix is a secondary structure of proteins that occurs only very rarely in nature . Compared to the ubiquitous α-helix , which requires an average of 3.6 amino acids per turn , the π-helix has 4.4 amino acids. This makes the π-helix energetically more unstable than the α-helix. In proteins one can occasionally find α-helices, at the end of which there is a rotation of π-helix. There are no longer π-helices. The structure of the π-helix was discovered by Linus Pauling .

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 .