Superoxide Dismutase Activity Assay Kit (Colorimetric)

Supplementary info

Activity summary

Superoxide dismutase also called SOD functions as an antioxidant enzyme that converts superoxide radicals into oxygen and hydrogen peroxide. It plays a critical role in reducing oxidative stress in cells. The enzyme exists in several isoforms including SOD1 SOD2 and SOD3 each with different cellular localizations and cofactors. SOD1 or cytosolic copper-zinc superoxide dismutase has a mass of approximately 32 kDa and is found in the cytoplasm. SOD2 known as manganese superoxide dismutase is mitochondrial and shares similar antioxidant functions. SOD3 is extracellular and has a distinct expression pattern mostly found in tissues like lungs and blood vessels.

Biological function summary

SOD enzymes protect cells by dismutating reactive superoxide radicals preventing cellular damage and apoptosis. These enzymes although not forming large protein complexes have critical interactions with cellular systems maintaining redox balance. Superoxide radicals if not regulated can lead to lipid peroxidation DNA damage and protein oxidation disrupting normal cellular processes. Superoxide dismutases thereby hold a defensive position in maintaining physiological homeostasis.

Pathways

Superoxide dismutase enzymes especially within the reactive oxygen species (ROS) signaling pathway contribute to cellular defense mechanisms. In the antioxidant defense pathway SOD enzymes act alongside catalase and glutathione peroxidase. They modulate oxidative stress levels that play a signal transduction role in processes like cell proliferation and apoptosis. This activity links them with proteins like catalase which further catabolize hydrogen peroxide into water and oxygen completing the detoxification process initiated by SOD.

Associated diseases and disorders

Superoxide dismutases are associated with neurodegenerative diseases and cancer. Mutations in SOD1 have links to amyotrophic lateral sclerosis (ALS) where misfolded proteins lead to motor neuron degeneration. SOD activity levels altered oxidative stress responses and faulty mitochondrial functions connect with Alzheimer's disease. The disease associations also include seemingly related proteins like TDP-43 in ALS pointing towards a wider network of dysfunction in oxidative stress pathways.