Redox enzymes play a central role in maintaining cellular balance by regulating the production and elimination of reactive oxygen species (ROS). These enzymes either neutralize ROS to prevent damage or, in some cases, contribute to their formation.
Antioxidant redox enzymes are crucial for protecting cells from oxidative damage caused by environmental stress, aging, and disease.
- Superoxide Dismutase (SOD): Converts superoxide radicals into hydrogen peroxide.
- Catalase (CAT): Breaks down hydrogen peroxide into water and oxygen.
- Glutathione Reductase (GR): Regenerates reduced glutathione (GSH), essential for GPx activity.
- Ascorbate Peroxidase (APX): Uses ascorbate to neutralize hydrogen peroxide (mainly in plants).
- Peroxidase: Uses hydrogen peroxide (H₂O₂) to oxidize specific substrates.
- Glutathione Peroxidase (GPx): Catalyzes the reduction of various peroxide species, using reduced glutathione (GSH).
Prooxidant redox enzymes play a critical role in cellular metabolism and immune defense, but they also pose a risk when their activity becomes excessive or unregulated.
- Xanthine Oxidase (XO): Produces superoxide and hydrogen peroxide during purine metabolism.
