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Updated: Sep 14, 2025
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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
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Ultrahigh-resolution solid-state NMR for high-molecular weight proteins on GHz-class spectrometers
Songlin Wang1, Thirupathi Ravula2, John A Stringer3
1National Magnetic Resonance Facility at Madison (NMRFAM), University of Wisconsin-Madison, Madison, WI, USA.
Science Advances
|July 23, 2025
Summary
Ultrahigh field solid-state NMR achieves high resolution for large proteins. New methods overcome field drift and spin couplings, enabling detailed molecular studies.
Area of Science:
- Physical Chemistry
- Biophysics
- Spectroscopy
Background:
- Nuclear Magnetic Resonance (NMR) spectroscopy is vital in physical and life sciences.
- Ultrahigh field (UHF) NMR offers enhanced sensitivity and resolution.
- Solid-state NMR (SSNMR) is suitable for large, complex systems due to instrumentation constraints.
Purpose of the Study:
- To overcome limitations in UHF SSNMR resolution.
- To address line broadening from magnetic field drift and nuclear spin couplings.
- To expand the application of gigahertz-class NMR for biological molecule research.
Main Methods:
- Utilized external 2H lock to correct for magnetic field drift.
- Implemented long-observation-window band-selective homonuclear decoupling to suppress 13C couplings.
- Applied advanced techniques to gigahertz-class NMR spectrometers.
Main Results:
- Achieved better than 0.2 parts per million (ppm) resolution in proteins up to 144 kilodalton (kDa).
- Enabled unique site resolution for over 500 amide backbone pairs in 2D experiments.
- Demonstrated superior resolution compared to solution NMR for large biomolecules.
Conclusions:
- The developed methods significantly enhance resolution in UHF SSNMR.
- This advancement greatly expands the potential of gigahertz-class NMR for life science research.
- Site-specific resolution in large proteins is now achievable, surpassing solution-state NMR capabilities.
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