Human SOD3/EC-SOD Alexa Fluor™ Plus 488-conjugated Antibody

Superoxide Dismutases (SODs), originally identified as Indophenoloxidase (IPO), are enzymes that catalyze the conversion of naturally-occuring, but harmful, superoxide radicals into molecular oxygen and hydrogen peroxide. Superoxide Dismutases 3, SOD3, also known as extracellular (EC) SOD, is tetrameric glycoprotein with an apparent subunit molecular weight of about 30 kDa. Three isoenzymes of SOD have been identified and are functionally related but have very modest sequence homology. SOD3 shares 23% and 17% sequence identity with SOD1 and SOD2, respectively. SOD3 shares ~64% sequence homology with mouse and rat SOD3. Like SOD1, SOD3 binds one Cu²⁺ and Zn²⁺ ions per subunit but differs in sequence and tissue distribution. SOD3 is a secretory protein and is synthesized with a putative 18-amino acid signal peptide preceding the 222 amino acids in the mature SOD3. SOD3 is found in plasma, lymph, and synovial fluid as well as in tissues. SOD3 binds on the surface of endothelial cells through the heparan sulfate proteoglycan and eliminates the oxygen radicals from the NADP-dependent oxidative system of neutrophils.