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Updated: Jun 9, 2025
14:55
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
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Integrating 19F Distance Restraints for Accurate Protein Structure Determination by Magic Angle Spinning NMR
Brent R Runge1,2, Roman Zadorozhnyi1,2, Caitlin M Quinn1
1University of Delaware, Department of Chemistry and Biochemistry, Newark, Delaware 19716, United States.
Journal of the American Chemical Society
|October 23, 2024
Summary
Fluorine-19 fast magic angle spinning (MAS) NMR spectroscopy extends protein structure determination by providing longer interatomic distances. This method enhances the precision of tryptophan side chain conformations and protein regions near fluorine-containing residues.
Area of Science:
- Structural Biology
- Biophysics
- Nuclear Magnetic Resonance (NMR) Spectroscopy
Background:
- Solid-state NMR spectroscopy is crucial for protein structure determination.
- Traditional methods rely on distances up to 8 Å from carbon- and nitrogen-based experiments.
- Limitations exist in obtaining longer-range distance restraints for precise structural analysis.
Purpose of the Study:
- To demonstrate the utility of fluorine-19 (19F) fast MAS NMR spectroscopy for protein structure determination.
- To extract longer interatomic distances beyond the typical range of traditional NMR methods.
- To improve the precision of protein structure calculations using 19F-based restraints.
Main Methods:
- Utilized 4F-Trp,U-13C,15N crystalline Oscillatoria agardhii agglutinin (OAA).
- Employed 2D and 3D 19F-based dipolar correlation NMR experiments, including (H)CF, (H)CHF, and FF.
- Applied fast (60 kHz) magic angle spinning (MAS) conditions.
Main Results:
- Successfully obtained interatomic distances in the 8-16 Å range using 19F NMR.
- Incorporation of 19F-derived restraints improved the precision of Trp side chain conformations.
- Enhanced structural accuracy in regions near fluorine-containing residues and specific Trp pairs (W10/W17, W77/W84) in carbohydrate-binding loops.
Conclusions:
- 19F fast MAS NMR spectroscopy is a powerful tool for structural biology.
- This technique provides valuable long-range distance information complementary to traditional methods.
- Fluorine incorporation and 19F NMR enable more precise protein structure determination, especially in challenging regions.
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