Helices in Proteins
From Proteopedia
(fixing the sync (currently, it only works well when driven from the leftmost JSmol) SUCCESS!) |
(adding some links and utilities) |
||
Line 67: | Line 67: | ||
</table> | </table> | ||
+ | |||
+ | Change rendering: | ||
+ | <jmol> | ||
+ | <jmolButton> | ||
+ | <target>jmol_3</target> | ||
+ | <script>script applet * @{"define temp selected;select not alpha;color bluetint;select protein;wireframe only;wireframe off;select backbone;cpk 23%;wireframe 0.15;select temp;"};</script> | ||
+ | <text>backbone - ball and stick</text> | ||
+ | </jmolButton> | ||
+ | <jmolButton> | ||
+ | <target>jmol_3</target> | ||
+ | <script>script applet * @{"define temp selected;select not alpha;color bluetint;select protein;wireframe only;wireframe off;cpk 23%;wireframe 0.15;select temp;"};</script> | ||
+ | <text>backbone and sidechains - ball and stick</text> | ||
+ | </jmolButton> | ||
+ | <jmolButton> | ||
+ | <target>jmol_3</target> | ||
+ | <script>script applet * @{"define temp selected;select not alpha;color bluetint;select protein;wireframe only;wireframe off;cpk 100%;select temp;"};</script> | ||
+ | <text>spacefilling for all</text> | ||
+ | </jmolButton> | ||
+ | <jmolButton> | ||
+ | <target>jmol_3</target> | ||
+ | <script>script applet * @{"define temp selected;select protein;wireframe only;wireframe off;cartoon on;select alpha;cpk 23%;select temp;"};</script> | ||
+ | <text>reset (cartoons)</text> | ||
+ | </jmolButton> | ||
+ | </jmol> | ||
+ | |||
The alpha helix ([[User:Karsten Theis/alpha helix]]) is by far the most common helix. Note that it is a right-handed helix when formed with the common L-amino acids<ref name="novotny">PMID: 15740737</ref><ref name="jourdan">PMID: 12910453</ref><ref name="moradi">PMID: 19923435</ref>. (It is left-handed when formed with D-amino acids<ref name="novotny" /><ref name="jourdan" /><ref name="moradi" />.) When viewed from either end, right-handed helices turn clockwise when followed away from you. | The alpha helix ([[User:Karsten Theis/alpha helix]]) is by far the most common helix. Note that it is a right-handed helix when formed with the common L-amino acids<ref name="novotny">PMID: 15740737</ref><ref name="jourdan">PMID: 12910453</ref><ref name="moradi">PMID: 19923435</ref>. (It is left-handed when formed with D-amino acids<ref name="novotny" /><ref name="jourdan" /><ref name="moradi" />.) When viewed from either end, right-handed helices turn clockwise when followed away from you. |
Revision as of 19:11, 2 February 2018
Helical conformations in proteins
This page illustrates the 3 most common helical conformations (among secondary structures) found in proteins.
Each of the three examples below is a decapeptide fragment extracted from an actual protein structure in the PDB. They are shown using the same scale, for a better comparison (as a consequence, zoom in the Jmol applets is disabled).
To re-align the 3 models, either reload this page or uncheck the synchronization and click on each of the 3 green 'Reset' links.
310 helix | alpha helix | pi helix | ||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|
|
||||||||||||||||||
|
|
|
Change rendering:
The alpha helix (User:Karsten Theis/alpha helix) is by far the most common helix. Note that it is a right-handed helix when formed with the common L-amino acids[1][2][3]. (It is left-handed when formed with D-amino acids[1][2][3].) When viewed from either end, right-handed helices turn clockwise when followed away from you.
See Also
- Alpha helix
- jsmol helix builder
- Alpha helix at Wikipedia.
- 3-10 helix at Wikipedia.
- Pi helix at Wikipedia.
- Secondary structure
- Protein primary, secondary, tertiary and quaternary structure (slides for teaching)
- Estructuras primaria, secundaria, terciaria y cuaternaria de las proteínas (en formato de presentación)
References
- ↑ 1.0 1.1 Novotny M, Kleywegt GJ. A survey of left-handed helices in protein structures. J Mol Biol. 2005 Mar 25;347(2):231-41. PMID:15740737 doi:10.1016/j.jmb.2005.01.037
- ↑ 2.0 2.1 Jourdan F, Lazzaroni S, Mendez BL, Lo Cantore P, de Julio M, Amodeo P, Iacobellis NS, Evidente A, Motta A. A left-handed alpha-helix containing both L- and D-amino acids: the solution structure of the antimicrobial lipodepsipeptide tolaasin. Proteins. 2003 Sep 1;52(4):534-43. PMID:12910453 doi:http://dx.doi.org/10.1002/prot.10418
- ↑ 3.0 3.1 Moradi M, Babin V, Roland C, Darden TA, Sagui C. Conformations and free energy landscapes of polyproline peptides. Proc Natl Acad Sci U S A. 2009 Dec 8;106(49):20746-51. Epub 2009 Nov 18. PMID:19923435 doi:10.1073/pnas.0906500106