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Updated: May 18, 2026
14:55
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Carbon detected protein resonance assignment at 55 kHz magic-angle spinning
Evgeny Nimerovsky1, Partha Pyne1, Stefan Becker1
1Department of NMR-based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Faßberg 11, Göttingen 37077, Germany.
Biophysical Chemistry
|May 16, 2026
Summary
New carbon-detected nuclear magnetic resonance (NMR) experiments using fast magic-angle spinning (MAS) offer sensitive protein resonance assignment. These methods provide competitive sensitivity and avoid artifacts seen in proton-detected spectra, especially for proline residues.
Area of Science:
- Solid-state nuclear magnetic resonance (NMR) spectroscopy
- Protein structural biology
- Biophysics
Background:
- Magic-angle spinning (MAS) NMR is crucial for solid protein analysis.
- Faster MAS rates enable proton-detected strategies, reducing sample needs.
- Carbon-detected experiments have historically been less sensitive for solid proteins.
Purpose of the Study:
- To demonstrate the utility of carbon-detected experiments at fast MAS rates (55 kHz).
- To introduce novel pulse sequences for linking sequential amino acid resonances.
- To compare the sensitivity and performance of new carbon-detected sequences against proton-detected ones.
Main Methods:
- Development and application of two new carbon-detected pulse sequences: (H)CAN(CO)CA and (H)CON(CA)CO.
- Utilizing fast MAS (55 kHz) with low-power decoupling and optimized magnetization transfer.
- Testing sequences on microcrystalline proteins, membrane proteins, and fibrils.
Main Results:
- The new sequences successfully linked sequential CA-CA and CO-CO resonances, with N as the 3rd dimension.
- Sensitivity was maintained at fast MAS rates, even with small sample volumes.
- Carbon-detected spectra showed competitive sensitivity to proton-detected spectra and lacked undesirable diagonal peaks.
- Proline residue assignment was notably improved due to the absence of amide protons in these spectra.
Conclusions:
- Carbon-detected experiments at fast MAS rates are surprisingly effective for solid protein assignment.
- The introduced sequences offer a valuable alternative to proton-detected methods, particularly for proline-rich proteins.
- These methods require minimal instrument time and provide high-quality data for diverse protein samples.
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