Detection of Proteoforms Using Top-Down Mass Spectrometry and Diagnostic Ions
Didia Coelho Graça1,2, Ralf Hartmer3, Wolfgang Jabs4
1Clinical Proteomics and Chemistry Group, Faculty of Medicine, University of Geneva, Geneva, Switzerland. didia.coelhograca@hcuge.ch.
Methods in Molecular Biology (Clifton, N.J.)
|March 11, 2019
Summary
Identify protein mass changes quickly using top-down mass spectrometry (TD MS) and electron transfer dissociation (ETD). This method reliably characterizes unknown samples by analyzing diagnostic ions within hours.
Area of Science:
- Proteomics
- Mass Spectrometry
- Structural Biology
Background:
- Protein structure modifications are crucial in proteomics.
- Accurate characterization of these modifications is essential for understanding protein function.
Purpose of the Study:
- To develop a rapid and reliable method for identifying mass changes in targeted protein sequences.
- To establish a workflow for top-down mass spectrometry (TD MS) using electron transfer dissociation (ETD).
Main Methods:
- Utilized top-down mass spectrometry (TD MS) with electron transfer dissociation (ETD).
- Developed a step-by-step procedure for TD MS method development and data acquisition.
- Implemented a data analysis process incorporating diagnostic ions.
Main Results:
- Successfully identified mass changes in targeted protein sequences.
- The TD MS workflow enabled rapid characterization of unknown samples.
- Diagnostic ions proved effective for sample analysis.
Conclusions:
- The described TD MS workflow offers a fast and reliable approach for protein mass change characterization.
- This method enhances the analysis of protein structure modifications in proteomics.
- The protocol facilitates efficient characterization of unknown protein samples.
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