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Updated: Aug 25, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Assignment of protein backbone resonances using connectivity, torsion angles and 13Calpha chemical shifts
Laura C Morris1, Homayoun Valafar, James H Prestegard
1Complex Carbohydrate Research Center, University of Georgia, 220 Riverbend Road, Athens, GA 30602-4712, U.S.A.
Abstract:
A program is presented which will return the most probable sequence location for a short connected set of residues in a protein given just (13)C(alpha) chemical shifts (delta((13)C(alpha))) and data restricting the phi and psi backbone angles. Data taken from both the BioMagResBank and the Protein Data Bank were used to create a probability density function (PDF) using a multivariate normal distribution in delta((13)C(alpha)), phi, and psi space for each amino acid residue. Extracting and combining probabilities for particular amino acid residues in a short proposed sequence yields a score indicative of the correctness of the proposed assignment. The program is illustrated using several proteins for which structure and (13)C(alpha) chemical shift data are available.
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