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Updated: Jul 15, 2026
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Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics
Published on: April 17, 2017
Characterizing protein structure in amorphous solids using hydrogen/deuterium exchange with mass spectrometry
Yunsong Li1, Todd D Williams, Richard L Schowen
1Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS 66047, USA.
Analytical Biochemistry
|May 11, 2007
Summary
Understanding protein structure in lyophilized drugs is key for stability. Hydrogen/deuterium exchange mass spectrometry reveals site-specific structural changes influenced by excipients like calcium and trehalose.
Area of Science:
- Pharmaceutical Sciences
- Biophysical Chemistry
- Structural Biology
Background:
- Rational drug design requires understanding protein structure in amorphous solids.
- Lyophilized protein formulations are crucial for drug stability and delivery.
Purpose of the Study:
- To investigate site-specific protein structural changes in amorphous solids using hydrogen/deuterium exchange mass spectrometry.
- To assess the influence of relative humidity, calcium chloride, and trehalose on protein structure.
Main Methods:
- Lyophilized calmodulin (17 kDa) powders were exposed to deuterium (D2O) vapor.
- Hydrogen/deuterium (H/D) exchange was monitored using electrospray ionization mass spectrometry.
- Experiments were conducted at controlled relative humidity and temperature.
Main Results:
- H/D exchange was sensitive to relative humidity and the presence of calcium chloride and trehalose.
- Structural changes occurred in a site-specific manner along the calmodulin backbone.
- Calcium primarily affected calcium-binding loops, while trehalose influenced alpha-helices.
Conclusions:
- Hydrogen/deuterium exchange mass spectrometry provides quantitative, site-specific structural insights into proteins in amorphous solids.
- This method reveals how cofactors and excipients modulate protein structure.
- The findings offer valuable data for designing stable lyophilized protein drugs, surpassing limitations of other solid-state techniques.
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