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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
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Solid-state NMR spectroscopy based atomistic view of a membrane protein unfolding pathway
Peng Xiao1, David Bolton1, Rachel A Munro1
1Department of Physics and Biophysics Interdepartmental Group, University of Guelph, 50 Stone Road E., Guelph, ON, N1G 2W1, Canada.
Nature Communications
|August 29, 2019
Summary
This study introduces a new method combining hydrogen-deuterium exchange and solid-state NMR to observe membrane protein unfolding in lipid bilayers. It reveals atomic details of a photoreceptor
Area of Science:
- Biochemistry
- Structural Biology
- Biophysics
Background:
- Membrane protein folding, structure, and function are critically dependent on the lipid bilayer environment.
- Characterizing protein folding dynamics within a membrane remains a significant experimental challenge.
- Studies on reversible unfolding provide insights into the energetics and stability of proteins.
Purpose of the Study:
- To develop and validate a novel methodology for studying membrane protein unfolding at atomic resolution within a lipid bilayer.
- To investigate the reversible unfolding pathway of a seven-helical photoreceptor using an integrated experimental approach.
- To characterize the unfolding intermediate and identify factors contributing to protein stability in a membrane environment.
Main Methods:
- Integration of hydrogen-deuterium (H/D) exchange with solid-state NMR (SSNMR) spectroscopy.
- Monitoring changes in protein water-accessible surface area during thermal-induced unfolding.
- Acquiring SSNMR-detected H/D exchange patterns at various temperatures to capture unfolding snapshots.
Main Results:
- An atomistic description of the reversible unfolding pathway of a seven-helical photoreceptor was obtained.
- The methodology successfully detected changes in H/D exchange patterns, visualizing the unfolding process.
- An unfolding intermediate was identified, along with its stabilizing interactions within the lipid membrane.
Conclusions:
- The combined H/D exchange and SSNMR approach provides atomic resolution insights into membrane protein unfolding dynamics.
- This method is transferable to other membrane proteins, offering new avenues for characterizing their stability and interactions.
- Understanding unfolding pathways and stabilizing factors is crucial for elucidating membrane protein function.
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