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Updated: Jul 5, 2026
08:51
Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
Electron capture/transfer versus collisionally activated/induced dissociations: solo or duet?
Roman A Zubarev1, Alexander R Zubarev, Mikhail M Savitski
1Division of Molecular Biometry, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden. roman.zubarev@icm.uu.se
Summary
Combining electron capture/transfer dissociation (ExD) with collisional excitation (CxD) improves peptide sequencing. This approach enhances data completeness for proteomics, especially in high-resolution mass spectrometry.
Area of Science:
- Proteomics and Mass Spectrometry
- Biophysical Chemistry
- Computational Biology
Background:
- Electron capture dissociation (ECD) and electron-transfer dissociation (ETD) are novel ion fragmentation techniques.
- These ExD technologies are increasingly adopted in high-throughput proteomics.
- Conventional collision-induced dissociation (CID)/collision-activated dissociation (CAD) (CxD) is widely used.
Purpose of the Study:
- To advocate for the synergistic integration of ExD and CxD techniques in mass spectrometry.
- To address limitations in sequence information completeness inherent in individual fragmentation methods.
- To highlight the benefits of combined ExD and CxD for de novo sequencing in proteomics.
Main Methods:
- Critical analysis of existing ion fragmentation technologies (ExD and CxD).
- Evaluation of database searching vulnerabilities in MS/MS-based proteomics.
- Assessment of de novo sequencing strategies using combined fragmentation data.
Main Results:
- Individual ExD or CxD methods yield incomplete peptide sequence information, complicating database searches.
- Peptide MS/MS homology presents a significant challenge for accurate protein identification.
- Combined ExD and CxD approaches significantly enhance sequence information acquisition.
Conclusions:
- De novo sequencing, enabled by combined ExD and CxD, is essential for overcoming data incompleteness.
- The benefits of integrating ExD and CxD, particularly additional sequence data, outweigh implementation costs.
- High-resolution mass spectrometry instruments are expected to benefit most from combined ExD and CxD strategies.
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