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Updated: Aug 1, 2026
12:07
Profiling Thiol Redox Proteome Using Isotope Tagging Mass Spectrometry
Published on: March 24, 2012
Roles of thiol-redox pathways in bacteria
1Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA. dritz@beckwith.med.harvard.edu
Annual Review of Microbiology
|September 7, 2001
Summary
Protein disulfide bonds are crucial for structure and function. Specialized enzymes catalyze their formation and reduction, with cellular location and redox state significantly influencing these processes.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Disulfide bonds are vital for protein structure and function, acting as either stable structural elements or transient participants in cellular processes.
- Their formation and reduction in vivo are catalyzed by thiol-disulfide exchanging enzymes featuring a conserved Cys-X-X-Cys active site motif.
- These enzymes are specialized for either oxidative or reductive roles.
Purpose of the Study:
- To explore the critical roles of disulfide bonds in protein structure and function.
- To investigate the enzymatic mechanisms governing disulfide bond formation and reduction.
- To highlight the importance of cellular compartmentalization and redox state in regulating disulfide bond dynamics.
Main Methods:
- Review of existing literature on protein disulfide bond biology.
- Analysis of enzyme active site motifs (Cys-X-X-Cys).
- Examination of cellular redox pathways and compartment-specific regulation.
Main Results:
- Disulfide bond formation and reduction are catalyzed by specific enzymes with distinct structural and functional specializations.
- Cellular redox potential, spatial distribution within compartments, and overall cellular redox state are critical regulators.
- Cytoplasmic pathways redundantly reduce disulfide bonds, with component expression responding to redox equilibrium.
- The periplasm hosts distinct systems for thiol oxidation and disulfide reduction, with novel electron translocation mechanisms.
Conclusions:
- Disulfide bond homeostasis is a complex process influenced by enzymatic activity, cellular compartmentalization, and redox environment.
- Understanding these regulatory mechanisms is key to comprehending protein function and cellular physiology.
- Further research into electron translocation mechanisms in the periplasm is warranted.
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