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14:55
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
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Assignment of oriented sample NMR resonances from a three transmembrane helix protein
D T Murray1, I Hung2, T A Cross3
1Institute for Molecular Biophysics, Florida State University, Tallahassee, FL 32306, USA; National High Magnetic Field Laboratory, Tallahassee, FL 32310, USA.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|February 11, 2014
Summary
Solid-state NMR now determines structures of three-helix membrane proteins. A new assignment strategy overcomes previous limitations, enabling routine structural characterization of larger membrane proteins.
Area of Science:
- Biophysics
- Structural Biology
- Biochemistry
Background:
- Oriented sample solid-state NMR is established for 1-2 transmembrane helix proteins.
- Larger membrane proteins pose challenges due to spectral resolution and assignment difficulties.
Purpose of the Study:
- To develop and apply a resonance assignment strategy for three-transmembrane helix proteins using solid-state NMR.
- To expand the utility of solid-state NMR for characterizing complex membrane protein structures.
Main Methods:
- Devised a novel resonance assignment strategy for solid-state NMR.
- Applied the strategy to a protein with three transmembrane helices.
- Obtained sequence-specific assignments for labeled transmembrane amino acid sites.
Main Results:
- Successfully obtained sequence-specific resonance assignments for all labeled transmembrane amino acid sites.
- Generated orientational restraints and determined helix orientations within the lipid bilayer.
- Demonstrated the feasibility of the strategy for proteins with multiple transmembrane helices.
Conclusions:
- The developed strategy significantly enhances solid-state NMR's capability for membrane protein structure determination.
- This approach facilitates routine structural characterization of proteins with three or more transmembrane helices.
- Represents a significant advancement in the structural analysis of complex membrane proteins.
Keywords:
Helix orientationLipid bilayerMembrane proteinMembrane protein structureMycobacterium tuberculosisOriented sample solid state NMRResonance assignmentMore Related Videos
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