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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Coherence transfer between spy nuclei and nitrogen-14 in solids
Simone Cavadini1, Anuji Abraham, Geoffrey Bodenhausen
1Laboratoire de Résonance Magnétique Biomoléculaire, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne, Batochime, CH-1015 Lausanne, Switzerland. Simone.Cavadini@epfl.ch
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|November 6, 2007
Summary
Nuclear Magnetic Resonance (NMR) spectroscopy uses spy nuclei like hydrogen-1 and carbon-13 to detect nitrogen-14 coherences. This method enables the determination of nitrogen-14 quadrupolar parameters in amino acids.
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Quantum Coherence Transfer
- Solid-State NMR
Background:
- Nitrogen-14 (I=1) NMR spectroscopy is challenging due to its quadrupolar interactions.
- Traditional methods for studying nitrogen nuclei often require isotopic enrichment or specialized techniques.
- Efficient coherence transfer mechanisms are crucial for sensitive NMR detection of quadrupolar nuclei.
Purpose of the Study:
- To develop a novel NMR method for exciting single- and double-quantum coherences of nitrogen-14.
- To utilize coherence transfer from abundant spin-1/2 nuclei (e.g., hydrogen-1, carbon-13) as 'spy nuclei'.
- To determine nitrogen-14 quadrupolar parameters in amino acids using magic-angle spinning.
Main Methods:
- Employed coherence transfer from spin-1/2 nuclei (hydrogen-1, carbon-13) to nitrogen-14.
- Utilized heteronuclear single-quantum correlation (HSQC)-like spectroscopy principles.
- Incorporated magic-angle spinning to enable coherence transfer via scalar couplings and residual dipolar splittings (RDS).
Main Results:
- Successfully excited single- and double-quantum coherences of nitrogen-14 nuclei.
- Observed second-order quadrupolar powder patterns in two-dimensional NMR spectra.
- Demonstrated the capability to determine nitrogen-14 quadrupolar parameters in amino acids.
Conclusions:
- Coherence transfer from abundant spy nuclei provides an effective route to study nitrogen-14.
- The method allows for the characterization of nitrogen-14 quadrupolar interactions without isotopic enrichment.
- This technique offers a valuable tool for structural and dynamic studies of biomolecules containing nitrogen-14.
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