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Identifying Functional Cysteine Residues in the Mitochondria
Daniel W Bak1, Mattia D Pizzagalli1, Eranthie Weerapana1
1Department of Chemistry, Boston College , Chestnut Hill, Massachusetts 02467, United States.
ACS Chemical Biology
|February 4, 2017
Summary
Mitochondria contain many cysteine residues that respond to redox changes. A new isolation method significantly enhances the study of these mitochondrial proteins and their modifications.
Area of Science:
- Cellular Biology
- Biochemistry
- Proteomics
Background:
- Mitochondria regulate cellular metabolism and redox balance.
- Mitochondrial proteins contain cysteine residues sensitive to redox environment changes.
- Current methods poorly represent mitochondrial proteins in cysteine reactivity studies.
Purpose of the Study:
- To develop a method for enhanced analysis of the mitochondrial cysteine proteome.
- To identify and characterize cysteine modifications in mitochondria.
- To investigate mitochondrial responses to redox and nitrosative stress.
Main Methods:
- Mitochondrial isolation and purification protocol.
- Cysteine-reactive chemical probes.
- Quantitative mass spectrometry (MS).
Main Results:
- Over 1500 cysteine residues from ~450 mitochondrial proteins identified.
- Identification of hyper-reactive cysteines with potential regulatory roles.
- Discovery of novel S-nitrosation sites on mitochondrial proteins under nitrosative stress.
Conclusions:
- A novel mitochondrial enrichment strategy substantially improves mitochondrial cysteine proteome coverage.
- This method enables detailed characterization of mitochondrial protein modifications.
- Provides insights into mitochondrial redox homeostasis and nitrosative stress responses.
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