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Updated: Jul 11, 2026
07:40
Disentangling Glycan-Protein Interactions: Nuclear Magnetic Resonance (NMR) to the Rescue
Published on: May 17, 2024
Structure of outer membrane protein G by solution NMR spectroscopy
1Department of Molecular Physiology and Biological Physics, University of Virginia, 1300 Jefferson Park Avenue, PO Box 800736, Charlottesville, VA 22908, USA.
Summary
The bacterial outer membrane protein G (OmpG) solution structure reveals a flexible loop region. This pH-gated porin
Area of Science:
- Structural Biology
- Biochemistry
- Microbiology
Background:
- The bacterial outer membrane protein G (OmpG) functions as a monomeric, pH-gated porin.
- Understanding OmpG's structure is crucial for deciphering its role in bacterial physiology and potential as a drug target.
Purpose of the Study:
- To determine the solution structure of OmpG using Nuclear Magnetic Resonance (NMR) spectroscopy.
- To investigate the structural dynamics and flexibility of OmpG in a micelle environment.
Main Methods:
- Overexpression and refolding of OmpG in Escherichia coli.
- Structure determination using solution NMR spectroscopy at pH 6.3.
- Utilized TROSY-based 3D experiments and NOE analysis for structural elucidation.
Main Results:
- Complete backbone assignments for 234 of 280 residues were achieved.
- The 14-stranded beta-barrel fold determined is consistent with crystal structures.
- Solution structure analysis revealed significant flexibility in the loop regions of OmpG.
Conclusions:
- OmpG exhibits a stable beta-barrel core with dynamic loop regions in solution.
- The observed loop flexibility may be critical for the pH-gated porin function of OmpG.
- NMR provides valuable insights into the dynamic nature of outer membrane proteins.
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