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Updated: May 10, 2026
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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Proton-detected solid-state NMR spectroscopy at aliphatic sites: application to crystalline systems
1Deutsches Forschungszentrum für Gesundheit und Umwelt (HMGU), Helmholtz-Zentrum München , Ingolstädter Landstr. 1, D-85764 Neuherberg, Germany.
Accounts of Chemical Research
|June 11, 2013
Summary
Solid-state NMR of biomolecules is enhanced using a novel Reduced Adjoining Protonation (RAP) labeling scheme. This method improves sensitivity and resolution for observing aliphatic protons, aiding protein structure and dynamics studies.
Area of Science:
- Biochemistry and Biophysics
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Structural Biology
Background:
- Solid-state NMR of biomolecules faces challenges with low sensitivity and resolution.
- The proton dipolar network hinders proton detection in solid-state NMR.
- Previous research focused mainly on exchangeable protons.
Purpose of the Study:
- To present NMR spectroscopic strategies for high-sensitivity and resolution observation of aliphatic non-exchangeable proton resonances in proteins.
- To introduce the Reduced Adjoining Protonation (RAP) labeling scheme for improved solid-state NMR.
- To enable detailed studies of protein structure and dynamics.
Main Methods:
- Utilized a labeling scheme based on u-[(2)H,(13)C]-glucose and 5-25% H2O (95-75% D2O) in M9 medium (RAP labeling).
- Employed specialized NMR experiments like ((1)H)CC(1)H, CC(1)H, (1)HCC, and ((2)H)CC(1)H.
- Incorporated isotopic labeling with [1,3]-(13)C-glycerol, [2]-(13)C-glycerol, or selectively enriched glucose for protonated samples.
Main Results:
- Achieved high sensitivity and resolution for aliphatic non-exchangeable proton resonances.
- Developed spectroscopic approaches for resonance assignments in proteins.
- Enabled measurement of long-range proton contacts for 3D structure calculations.
- Obtained dynamic parameters like T1 relaxation times and S(2) order parameters.
Conclusions:
- The RAP labeling scheme significantly enhances solid-state NMR for biomolecules.
- This approach facilitates detailed analysis of protein structure and dynamics.
- Opens new avenues for understanding protein backbone and side chain dynamics.
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