Quick Search:

uzh logo
Browse by:
bullet
bullet
bullet
bullet

Zurich Open Repository and Archive 

Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-24997

Backus, E H G; Bloem, R; Pfister, R; Moretto, A; Crisma, M; Toniolo, C; Hamm, P (2009). Dynamical Transition in a Small Helical Peptide and Its Implication for Vibrational Energy Transport. Journal of Physical Chemistry. B, 113(40):13405-13409.

[img] PDF - Registered users only
1MB

Abstract

The two-dimensional infrared spectrum of an octameric helical peptide in chloroform was measured as a function of temperature. Isotope labeling of the carbonyl group of one of the amino acids was used to obtain information for an isolated vibration. The antidiagonal width of the 2D-IR signal, which is a measure of the homogeneous dephasing time T2, is constant from 220 to 260 K (within experimental error), and increases steeply above. The homogeneous dephasing time of the carbonyl vibration is attributed to the flexibility of the system and/or its immediate surrounding. The system undergoes a dynamical transition at about 270 K, with similarities to the protein dynamical transition. Furthermore, the temperature dependence of the antidiagonal width strongly resembles that of the efficiency of vibrational energy transport along the helix, which has been studied in a recent paper (J. Phys. Chem. B 2008, 112, 15487). The connection between the two processes, structural flexibility and energy transport mechanism, is discussed.

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Chemistry
DDC:540 Chemistry
Language:English
Date:15 September 2009
Deposited On:31 Dec 2009 09:55
Last Modified:05 Jun 2014 13:50
Publisher:American Chemical Society
ISSN:1520-5207
Funders:The Netherlands Organisation for Scientific Research (NWO) , Swiss National Science Foundation
Publisher DOI:10.1021/jp904905d
Citations:Web of Science®. Times Cited: 12
Google Scholar™
Scopus®. Citation Count: 16

Users (please log in): suggest update or correction for this item

Repository Staff Only: item control page