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Paramagnetic Relaxation Enhancement for Detecting and Characterizing Self-Associations of Intrinsically Disordered Proteins
Published on: September 23, 2021
Improved pulse sequences for sequence specific assignment of aromatic proton resonances in proteins
Frank Löhr1, Robert Hänsel, Vladimir V Rogov
1Institute of Biophysical Chemistry, Centre for Biomolecular Magnetic Resonance, Johann Wolfgang Goethe-University, Frankfurt, Germany. murph@bpc.uni-frankfurt.de
Journal of Biomolecular NMR
|January 24, 2007
Summary
New nuclear magnetic resonance (NMR) methods simplify aromatic proton assignment in proteins. These through-bond experiments use standard hardware for efficient sequential assignment, aiding protein structure determination.
Area of Science:
- Structural Biology
- Biophysical Chemistry
- Nuclear Magnetic Resonance Spectroscopy
Background:
- Aromatic proton resonance assignment in proteins is challenging.
- Through-bond correlation experiments offer advantages over through-space methods for independent assignment.
- Existing through-bond methods have limitations in efficiency and hardware requirements.
Purpose of the Study:
- To develop novel through-bond NMR experiments for sequential assignment of aromatic protons.
- To enable aromatic chemical shift assignment independent of protein structure determination.
- To utilize standard NMR spectrometer hardware for improved accessibility.
Main Methods:
- Proposed novel pulse sequences for magnetization transfer across Cbeta-Cgamma bonds in aromatic side chains.
- Experiments correlate ring protons with beta-carbons, amide protons/nitrogens, or carbonyls.
- Utilized uniformly 13C/15N labeled proteins and standard spectrometer hardware.
Main Results:
- Demonstrated sequential assignment of all aromatic protons in four proteins (11-23 kDa).
- Achieved efficient magnetization relay beyond the Cdelta position.
- Developed non-selective and amino-acid type selective spectral acquisition modes.
Conclusions:
- The novel methods provide efficient and accessible routes for aromatic proton assignment in proteins.
- These techniques simplify protein resonance assignment and structural analysis.
- Standard hardware compatibility enhances the applicability of these NMR strategies.
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