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Updated: Jul 18, 2026
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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Structure, dynamics and topology of membrane polypeptides by oriented 2H solid-state NMR spectroscopy
Christopher Aisenbrey1, Philippe Bertani, Peter Henklein
1Faculté de Chimie, Institut le Bel, Université Louis Pasteur/CNRS, LC3-UMR7177, Strasbourg, France.
European Biophysics Journal : EBJ
|December 21, 2006
Summary
Solid-state NMR using deuterium labeling reveals polypeptide tilt and rotation within membranes. This method analyzes viral channel peptides, suggesting an equilibrium between monomeric and oligomeric states.
Area of Science:
- Biophysics
- Structural Biology
- Nuclear Magnetic Resonance (NMR) Spectroscopy
Background:
- Understanding polypeptide interactions with phospholipid bilayers is crucial for deciphering the function of membrane proteins like channels and peptides.
- Solid-state NMR spectroscopy on aligned samples provides insights into polypeptide structure and dynamics relative to the bilayer normal.
Purpose of the Study:
- To introduce and apply deuterium (2H) solid-state NMR spectroscopy for precise determination of polypeptide tilt and rotation angles within phospholipid bilayers.
- To investigate the structural organization and aggregation states of viral channel peptides, Vpu(1-27) and Influenza A M2(22-46).
Main Methods:
- Utilizing (15)N chemical shifts to estimate helical tilt and (2)H solid-state NMR of specifically labeled peptides (3,3,3-(2)H(3)-alanines) for detailed tilt and rotation analysis.
- Analyzing deuterium NMR line shapes sensitive to C(alpha)-C(beta) bond orientation and rotational diffusion rates in oriented membrane samples.
Main Results:
- Deuterium NMR provides complementary information to (15)N chemical shifts for accurate analysis of polypeptide orientation, including tilt and rotation pitch angles.
- (15)N chemical shifts confirmed transmembrane helix alignment for Vpu(1-27) and M2(22-46) peptides.
- Deuterium spectra revealed significant mosaic spread in helix orientations and suggested the presence of at least two peptide populations with different rotational correlation times, indicative of monomer-oligomer equilibrium.
Conclusions:
- Deuterium solid-state NMR is a powerful technique for characterizing polypeptide orientation and dynamics in membranes, complementing traditional (15)N NMR.
- Viral channel peptides Vpu and M2 exhibit heterogeneous orientations and exist in an equilibrium between monomeric and oligomeric forms.
- This study advances the structural analysis of membrane-associated peptides using advanced NMR methodologies.
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