Low-frequency Raman spectra of amyloid fibrils
Abstract
We report on how low-frequency Raman measurements can be used as a facile tool to investigate the supramolecular structure of amyloid fibrils. We investigate the low-frequency Raman spectra (<500 cm−1) of six different amyloid fibrils exhibiting parallel β-sheet structures prepared from amyloid-β1–40, amylin, amyloid-β25–35, and amylin20–29 peptides. We propose band assignments using a combination of semi-empirical tight-binding calculations and insights gleaned from previously published studies on model polypeptides in β-sheet conformations. We discuss how low-frequency Raman modes can be used to probe the interactions, packing, and ordering of strands and side chains within fibril β-sheets to gain insights into their supramolecular structures.
Article Details
Journal Info
The Journal of Chemical Physics
American Institute of Physics
Authors (8)
Madeline Harper
Department of Chemistry, University of Vermont , Burlington, Vermont 05405,
Amanda Dumi
Sandia National Laboratories 2 , Albuquerque, New Mexico 87185,
Shiv Upadhyay
Department of Chemistry
Riley J. Workman
Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch 4 , Galveston, Texas 77555,
Delaney Nelson
Department of Chemistry, University of Vermont 1 , Burlington, Vermont 05405,
Uma Nudurupati
Department of Chemistry, University of Vermont 1 , Burlington, Vermont 05405,
Yangguang Ou
Department of Chemistry, University of Vermont 1 , Burlington, Vermont 05405,
David Punihaole
Department of Chemistry, University of Vermont , Burlington, Vermont 05405,