69 by: Stephanie Orduz Ponguta
Student – Stephanie Orduz Ponguta
Enzyme – superoxide dismutase
E.C. number – 1.15.1.1.
Superoxide dismutase is found in most living organisms in the cytosol called SOD 1, the mitochondria called SOD 2, and the extracellular fluid called SOD 3. They also found that most strictly anaerobic species do not have superoxide dismutase or catalase. Superoxide dismutase catalyzes 2 molecules of superoxide (oxygen radical) using a metal cofactor such as Copper-Zinc (or Mn in the mitochondria) by oxidation/reduction. The first superoxide gets oxidized by the Cu ligand. The second gets oxidized by the Cu ligand allowing the superoxide to protonate itself and convert into hydrogen peroxide which is then catalyzed by catalase. Superoxide is extremely reactive and can bind to aconitase in the TCA cycle which would release iron ions into the body that could damage DNA and other cellular constituents. The mechanism is also completely inorganic as it only uses metal ligands and proton transfers. It has the highest catalytic efficiency of any enzyme.
References
- Superoxides and Superoxide Dismutase: Physiology, Biochemistry, and Inorganic Mechanism. (n.d.). Www.youtube.com. Retrieved May 29, 2021, from https://www.youtube.com/watch?v=8doesahSy4w
- Group, T. (2016). M-CSA Mechanism and Catalytic Site Atlas. Ebi.ac.uk. https://www.ebi.ac.uk/thornton-srv/m-csa/entry/138/
- Moldoveanu, S., & David, V. (2022). Equilibrium types in HPLC. Essentials in Modern HPLC Separations, 107–146. https://doi.org/10.1016/b978-0-323-91177-1.00005-3
- Imidazole | organic compound class. (n.d.). Encyclopedia Britannica. https://www.britannica.com/science/imidazole-organic-compound-class
