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Updated: Aug 18, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Dissecting coherent vibrational spectra of small proteins into secondary structural elements by sensitivity analysis
Wei Zhuang1, Darius Abramavicius, Shaul Mukamel
1Department of Chemistry, University of California, Irvine, CA 92697-2025, USA.
Abstract:
The response of proteins to sequences of femtosecond infrared pulses provides a multidimensional view into their equilibrium distribution of structures and snapshot pictures of fast-triggered dynamical events. Analyzing these experiments requires advanced computational tools for assigning regions in the resulting multi-dimensional correlation plots to specific secondary-structure elements and their couplings. A differential sensitivity analysis technique based on a perturbation of the local (real space) Hamiltonian is developed to achieve that goal. Application to the amide I region of a small globular protein reveals regions associated with the alpha-helix, beta-sheet, and their coupling. Comparison of signals generated in different directions shows that the double-quantum-coherence signal has a higher sensitivity to the couplings compared with the single-quantum-coherence (photon echo) technique.
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