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Updated: May 28, 2026
14:55
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Ultrahigh resolution protein structures using NMR chemical shift tensors
Benjamin J Wylie1, Lindsay J Sperling, Andrew J Nieuwkoop
1Department of Chemistry, University of Illinois, 600 South Mathews Avenue, Urbana, IL 61801, USA.
Summary
This study determined chemical shift tensor (CST) magnitudes and orientations for protein backbone groups. These new restraints significantly improved protein structure determination using solid-state NMR.
Area of Science:
- Biophysics
- Structural Biology
- Nuclear Magnetic Resonance (NMR) Spectroscopy
Background:
- Nuclear Magnetic Resonance (NMR) chemical shift tensors (CSTs) and their orientations offer novel restraints for protein structure determination.
- Accurate protein structures are crucial for understanding biological function.
Purpose of the Study:
- To present the first determination of both CST magnitudes and orientations for carbon-13 (13Cα) and nitrogen-15 (15N) peptide backbone groups in a protein.
- To demonstrate the utility of CST restraints in refining protein structures.
Main Methods:
- Site-specific (13)Cα and (15)N CSTs were measured using synchronously evolved recoupling experiments.
- Tensors were projected onto relevant vectors, including (1)H-(13)C, (1)H-(15)N, and (15)N-(13)C.
- Ab initio calculations were used for comparison.
Main Results:
- The orientations of (13)Cα CSTs showed good agreement with ab initio calculations (rmsd ~8°).
- (15)N tensors displayed distinct anisotropies in α-helical versus β-sheet regions.
- Incorporating (13)Cα CST restraints improved backbone root-mean-square deviation (rmsd) to 0.16 Å.
Conclusions:
- Chemical shift tensors provide valuable restraints for protein structure refinement and de novo structure determination.
- The refined structures are comparable to high-resolution crystal structures.
- Solid-state NMR is enhanced as a powerful tool for structural biology.
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