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Updated: May 19, 2026
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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Very-long-distance correlations in proteins revealed by solid-state NMR spectroscopy
Bingwen Hu1, Julien Trébosc, Oliver Lafon
1Physics Department, Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, China. bwhu@phy.ecnu.edu.cn
Summary
A new pulse sequence, SHA+, enables observing carbon-13 (13C) atoms in amyloid fibrils up to 9.6 Å apart. This method is also suitable for studying temperature-sensitive biological systems.
Area of Science:
- Magnetic Resonance Spectroscopy
- Biophysics
- Structural Biology
Background:
- Amyloid fibrils are protein aggregates implicated in various diseases.
- Understanding the structure and dynamics of amyloid fibrils is crucial for disease mechanism elucidation.
- Current NMR techniques face limitations in probing long-range interactions within these systems.
Purpose of the Study:
- To introduce and validate a novel Nuclear Magnetic Resonance (NMR) pulse sequence, SHA+.
- To demonstrate the capability of SHA+ in detecting polarization transfer between distant carbon-13 (13C) nuclei in amyloid fibrils.
- To assess the applicability of SHA+ for investigating temperature-sensitive biological systems.
Main Methods:
- Development of the SHA+ (Solid-state Heteronuclear Assignment) pulse sequence.
- Application of SHA+ to amyloid fibril samples for assessing dipolar truncation sensitivity.
- Utilizing SHA+ under weak radiofrequency (rf) conditions (ν(1)/ν(R)≈0.2-0.3) for temperature-dependent studies.
Main Results:
- The SHA+ pulse sequence exhibits reduced sensitivity to dipolar truncation, a common artifact in solid-state NMR.
- SHA+ successfully enables direct or relayed polarization transfer between 13C atoms separated by distances of 3.5-9.6 Å within amyloid fibrils.
- The broadband application of SHA+ under weak rf conditions is compatible with temperature-sensitive biological systems.
Conclusions:
- SHA+ is a valuable new tool for structural and dynamic studies of amyloid fibrils using solid-state NMR.
- The sequence extends the reach of NMR for probing long-range interactions in supramolecular assemblies.
- SHA+ offers a promising approach for investigating the temperature-dependent behavior of biomolecular systems.
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