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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Peptides and proteins in the vapor phase
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USa. mfj@nwu.edu.
Annual Review of Physical Chemistry
|October 14, 2000
Summary
This review explores how studying unsolvated peptides and proteins in the vapor phase reveals their intrinsic properties. Techniques like H/D exchange and ion mobility provide insights into molecular interactions and hydration.
Area of Science:
- Biochemistry
- Chemical Physics
- Molecular Biophysics
Background:
- Understanding protein structure and function is crucial in biochemistry.
- Unsolvated peptides and proteins offer insights into intrinsic molecular properties.
- Gas-phase studies complement solution-phase analyses.
Purpose of the Study:
- To review recent advancements in studying unsolvated and partially solvated peptides and proteins.
- To detail methods for producing and analyzing gas-phase biomolecules.
- To summarize key findings regarding intrinsic properties and interactions.
Main Methods:
- Production of vapor-phase peptide and protein ions.
- Hydrogen/Deuterium (H/D) exchange for structural probing.
- Blackbody infrared radiative dissociation (BIRD) for stability analysis.
- Ion mobility measurements for size and shape determination.
Main Results:
- Gas-phase studies reveal intrinsic intramolecular interactions, including zwitterions and salt bridges.
- Analysis of Coulomb interactions in multiply charged ions.
- Observations on the unfolding and refolding dynamics of vapor-phase proteins.
- Detailed characterization of helix and sheet stability in unsolvated states.
- Quantification of hydration interactions through dehydration/rehydration studies.
Conclusions:
- Gas-phase ion spectroscopy provides unique insights into biomolecular structure and interactions.
- Dehydration and rehydration studies offer precise data on water molecule adsorption.
- These studies enhance our fundamental understanding of protein behavior.
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