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09:57
A Facile and Efficient Approach for the Production of Reversible Disulfide Cross-linked Micelles
Published on: December 23, 2016
Generating disulfides with the Quiescin-sulfhydryl oxidases
Erin J Heckler1, Pumtiwitt C Rancy, Vamsi K Kodali
1Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19711, USA.
Biochimica Et Biophysica Acta
|November 6, 2007
Summary
Quiescin-sulfhydryl oxidases (QSOX) are flavoenzymes that form disulfide bonds in proteins. This review explores their mechanism, structure, cellular roles, and remaining questions about these essential enzymes.
Area of Science:
- Biochemistry
- Enzymology
- Protein Folding
Background:
- Quiescin-sulfhydryl oxidase (QSOX) enzymes are flavoenzymes.
- They catalyze disulfide bond formation in proteins, a crucial step in oxidative protein folding.
- QSOX enzymes reduce oxygen to hydrogen peroxide during catalysis.
Purpose of the Study:
- To review the chemical mechanism of QSOX enzymes.
- To discuss the role of thioredoxin and flavin-binding domains in QSOX catalysis.
- To summarize the cellular location and potential roles of QSOX enzymes.
Main Methods:
- Literature review of QSOX enzymes.
- Analysis of catalytic mechanisms.
- Examination of protein structure-function relationships.
Main Results:
- QSOX enzymes facilitate disulfide bond insertion via a specific chemical mechanism.
- Variability in CxxC motifs and steric factors influence thiol/disulfide exchange efficiency.
- QSOX enzymes exhibit diverse cellular localization, suggesting varied functions.
Conclusions:
- QSOX enzymes are ancient and versatile sulfhydryl oxidases.
- Further research is needed to address unresolved questions regarding their function and regulation.
- Understanding QSOX is key to comprehending oxidative protein folding and cellular redox homeostasis.
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