In order to study the influence of Ser and Thr on the structure of transmembrane helices we have analyzed
a database of helix stretches extracted from crystal structures of membrane proteins and an ensemble
of model helices generated by molecular dynamics simulations. Both complementary analyses show
that Ser and Thr in the g ...»»»»
In order to study the influence of Ser and Thr on the structure of transmembrane helices we have analyzed
a database of helix stretches extracted from crystal structures of membrane proteins and an ensemble
of model helices generated by molecular dynamics simulations. Both complementary analyses show
that Ser and Thr in the g conformation induce and/or stabilize a structural distortion in the helix backbone.
Using quantum mechanical calculations, we have attributed this effect to the electrostatic repulsion
between the side chain Oc atom of Ser and Thr and the backbone carbonyl oxygen at position
i 3. In order to minimize the repulsive force between these negatively charged oxygens, there is a modest
increase of the helix bend angle as well as a local opening of the helix turn preceding Ser/Thr. This
small distortion can be amplified through the helix, resulting in a significant displacement of the residues
located at the other side of the helix. The crystal structures of aquaporin Z and the b2-adrenergic receptor
are used to illustrate these effects. Ser/Thr-induced structural distortions can be implicated in processes
as diverse as ligand recognition, protein function and protein folding.^^^^
Tipus:
Article
Indexació:
Indexat a WOS/JCR
Drets:
(c) 2010 Elsevier. Published article is available at: http://dx.doi.org/10.1016/j.jsb.2009.09.009
Citació Bibliogràfica:
Deupi, X., Olivella Garcia, M., Sanz, A., Doelker, N., Campillo, M., & Pardo, L. (2010). Influence of the g- conformation of Ser and Thr on the structure of transmembrane helices. Journal of structural biology, 169(1), 116-123. doi:10.1016/j.jsb.2009.09.009