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Updated: Jul 13, 2026
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Monitoring Protein-Ligand Interactions in Human Cells by Real-Time Quantitative In-Cell NMR using a High Cell Density Bioreactor
Published on: March 9, 2021
Optimal control based NCO and NCA experiments for spectral assignment in biological solid-state NMR spectroscopy.
Cindie Kehlet1, Morten Bjerring, Astrid C Sivertsen
1Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, Langelandsgade 140, DK-8000, Aarhus C, Denmark.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|August 8, 2007
Summary
New nuclear magnetic resonance (NMR) pulse sequences enhance protein structure determination. These optimized sequences improve sensitivity and robustness for solid-state NMR studies of isotope-labeled proteins.
Area of Science:
- Biophysics
- Structural Biology
- Biochemistry
Background:
- Solid-state Nuclear Magnetic Resonance (NMR) is crucial for determining the structure of biomolecules.
- Isotope labeling, particularly with Carbon-13 ((13)C) and Nitrogen-15 ((15)N), is essential for NMR structural studies.
- Efficient coherence transfer pathways are vital for spectral assignment in solid-state NMR.
Purpose of the Study:
- To develop and present novel pulse sequences for magic-angle-spinning (MAS) solid-state NMR.
- To improve sensitivity, robustness, and band-selective excitation for structural studies of (13)C,(15)N-labeled proteins.
- To optimize (15)N to (13)C coherence transfer for spectral assignment in solid-state NMR.
Main Methods:
- Numerical design of pulse sequences using optimal control procedures.
- Analysis of pulse sequence performance under high-field solid-state NMR conditions.
- Numerical illustration of robustness towards spin system and experimental parameters.
- Experimental validation using 1D, 2D, and 3D NMR experiments on uniformly (13)C,(15)N-labeled ubiquitin.
Main Results:
- Novel pulse sequences demonstrate superior sensitivity and robustness compared to existing methods.
- Optimized sequences provide improved band-selective excitation profiles for biological applications.
- Effective (15)N to (13)C coherence transfer pathways were designed and validated.
- Experimental results on ubiquitin confirm the practical utility of the new sequences.
Conclusions:
- The presented pulse sequences represent a significant advancement for solid-state NMR structural studies.
- These methods enhance the efficiency and reliability of spectral assignment for isotope-labeled proteins.
- The optimized sequences are broadly applicable to biological solid-state NMR research.
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