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Updated: Jun 13, 2025
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Neutron Spin Echo Spectroscopy as a Unique Probe for Lipid Membrane Dynamics and Membrane-Protein Interactions
Published on: May 27, 2021
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Correlating membrane-protein dynamics with function: Integrating bioinformatics, molecular dynamics, and
Hugh R Higinbotham1, Christine A Arbour2, Barbara Imperiali2
1Department of Biology and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Biorxiv : the Preprint Server for Biology
|June 12, 2025
Summary
We developed a new method combining structural bioinformatics, molecular simulation, and single-molecule FRET microscopy to observe how integral membrane proteins change shape when binding to ligands, aiding drug discovery.
Area of Science:
- Structural biology and biophysics of membrane proteins.
- Prokaryotic glycoconjugate biosynthesis pathways.
- Protein-ligand interactions and conformational dynamics.
Background:
- Integral membrane proteins play crucial roles in biological processes, and understanding their structure-function relationships is vital for drug development.
- Bacterial glycoconjugate biosynthesis pathways are attractive targets for novel antibiotics due to their essential roles and unique biochemical properties.
- Characterizing these systems presents challenges due to the complex interplay of proteins, lipids, and carbohydrates.
Purpose of the Study:
- To investigate the ligand-dependent conformational dynamics of small monotopic phosphoglycosyl transferase (SmPGT) superfamily members.
- To correlate structural features with observed dynamics and validate their role in ligand binding.
- To establish a versatile platform for studying protein dynamics in a native-like membrane environment.
Main Methods:
- Integration of structural bioinformatics, all-atom molecular simulations, and single-molecule Förster Resonance Energy Transfer (smFRET) microscopy.
- Development of a platform using selective cysteine labeling, non-canonical amino acid mutagenesis, and click chemistry for dual-labeling PglC variants.
- Solubilization of modified proteins into styrene maleic acid liponanoparticles (SMALPs) to mimic native membrane environments.
Main Results:
- Identification of substrate-specific structural features within the SmPGT superfamily.
- Correlation of these features with ligand-dependent conformational dynamics observed in molecular simulations.
- Experimental validation of protein motion's role in ligand binding using smFRET-SMALP technology.
- Demonstration that PglC conformational changes upon inhibitor binding correlate with inhibitor potency.
Conclusions:
- The developed smFRET-SMALP strategy effectively monitors in situ conformational dynamics of integral membrane proteins.
- This approach provides insights into the mechanism of ligand binding and inhibitor potency for the SmPGT superfamily.
- The methodology is adaptable for studying other SmPGT members with varying substrate specificities, supporting structure-based drug design.
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