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Updated: Jun 28, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Peptide C(alpha)D(alpha) stretch frequencies in a hydrated conformation are perturbed mainly by C(alpha)-D(alpha)...O
1LSA Biophysics, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, USA.
Abstract:
We have shown (J. Phys. Chem. A 2004, 108, 10923; 2007, 111, 5300) that the C(alpha)D(alpha) stretch frequency, nu(CD), can discriminate between uniform alpha(R), beta, and polyproline II conformations of isolated peptides. Similar results for such peptides to which explicit waters are hydrogen bonded exhibit shifts in nu(CD) from those of the isolated structures. We demonstrate that the main source of these frequency shifts is the formation of C(alpha)-D(alpha)...O hydrogen bonds to water. Taking into account C-H...O(water) hydrogen bonding, together with the traditional bonding of peptide groups to water, can be expected to increase our understanding of the interaction of proteins with their aqueous environment.
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