Magnetically-orientable Tween-based model membranes for NMR studies of proteins.
Andrée E Gravel1, Alexandre A Arnold1, Matthieu Fillion2
1Department of Chemistry, Université du Québec à Montréal, P.O. Box 8888, Montréal, QC, H3C 3P8, Canada.
Biochimica Et Biophysica Acta. Biomembranes
|June 1, 2020
Summary
We developed a novel membrane mimetic system using Tween 80 (TW80) for solid-state NMR. This system efficiently orients membrane proteins, aiding structural determination without detergent removal.
Area of Science:
- Biophysics
- Structural Biology
- Biochemistry
Background:
- Solid-state NMR is crucial for membrane protein structure determination.
- Existing methods often require complex detergent removal steps.
- Developing efficient, oriented membrane mimetics is essential.
Purpose of the Study:
- To introduce a new membrane mimetic system using Tween 80 (TW80) for solid-state NMR.
- To demonstrate the ability of TW80 to form oriented model membranes.
- To show the utility of this system for membrane protein structural studies.
Main Methods:
- Formation of phosphatidylcholine (PC)/TW80 model membrane systems.
- Characterization using solid-state NMR (31P, 2H, 15N) and FTIR spectroscopy.
- Utilizing lanthanide ions to control membrane alignment.
Main Results:
- DMPC and DPPC self-assembled with TW80 into oriented structures.
- Alignment was maintained across various molar ratios and temperatures.
- TW80-based membranes enabled peptide orientation determination via 15N NMR.
Conclusions:
- TW80 forms stable, oriented membrane mimetics suitable for solid-state NMR.
- This system facilitates membrane protein extraction and orientation without detergent removal.
- The approach is versatile and applicable to various membrane types, including native membranes.
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