Structural Transitions in the Polyalanine α-Helix under Uniaxial Strain.

We analyzed the response to strain of an infinite polyalanine chain in the α-helical conformation using density functional theory. Under compressive strain the π-helix is found to undergo structural transitions to a α-helix when the length of the helix is reduced by more than 10%. Under tensile stra...

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Detalles Bibliográficos
Publicado en:Journal of the American Chemical Society Vol. 127; no. 49; pp. 17241 - 17245
Autores principales: Ireta, Joel, Neugebauer, Jörg, Scheffler, Matthias, Rojo, Arturo, Galván, Marcelo
Formato: Artículo
Publicado: American Chemical Society 12/14/2005
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Acceso en línea:Ver este registro en EBSCOhost
Descripción
Sumario:We analyzed the response to strain of an infinite polyalanine chain in the α-helical conformation using density functional theory. Under compressive strain the π-helix is found to undergo structural transitions to a α-helix when the length of the helix is reduced by more than 10%. Under tensile strain the structure changes into a 3-helix when the length is stretched by more than 10%. Our analysis of these transitions shows that they proceed essentially in two steps: At first there is mainly a length change, and only with some delay the helix twist adjusts.