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07:33
Analyzing Protein Architectures and Protein-Ligand Complexes by Integrative Structural Mass Spectrometry
Published on: October 15, 2018
Ion mobility-mass spectrometry reveals conformational changes in charge reduced multiprotein complexes.
Russell E Bornschein1, Suk-Joon Hyung, Brandon T Ruotolo
1Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109, USA.
Journal of the American Society for Mass Spectrometry
|September 29, 2011
Summary
Gas-phase ion-neutral reactions effectively reduce protein complex charge, preserving native-like structures. Solution additives require more activation, leading to unfolded complexes, impacting structural biology research.
Area of Science:
- Structural biology
- Biophysics
- Mass spectrometry
Background:
- Ion mobility-mass spectrometry (IM-MS) is crucial for characterizing multiprotein complexes.
- Protein complex charge states significantly affect gas-phase measurement data.
- Charge state influences conformation, mass/ion mobility resolution, and dissociation properties.
Purpose of the Study:
- To compare charge reduction methods for multiprotein complexes.
- To evaluate the impact of charge reduction on complex conformation.
- To determine the optimal method for preserving native-like structures in IM-MS.
Main Methods:
- Ion mobility-mass spectrometry (IM-MS) was employed.
- Comparison of charge reduction via solution additives versus gas-phase ion-neutral reactions.
- Analysis of conformational changes in multiprotein complexes.
Main Results:
- Gas-phase ion-neutral reactions yielded compact, native-like protein assemblies.
- Solution additive methods required significant gas-phase activation for charge reduction.
- This activation led to unfolding of protein complexes, obscuring solution-phase structures.
Conclusions:
- Gas-phase ion-neutral reactions are superior for preserving native-like protein complex structures during charge reduction.
- Solution additive charge reduction strategies can induce conformational changes detrimental to structural biology.
- IM-MS can effectively differentiate conformational states resulting from different charge reduction techniques.
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