Superoxide Dismutase 1 (SOD1 or (Cu‐Zn) superoxide dismutase) is the initially discovered mammalian SOD, found in almost all cells, and functioning as an organism’s primary defense against highly toxic reactive oxygen species (ROS). ROS, produced as toxic byproducts of aerobic metabolism, can cause cell damage and apoptosis, and potentially contribute to diseases, including certain heart conditions, degenerative neural diseases, and various oxidative stress and age related disorders. There are three types of mammalian SOD proteins; SOD1, found in the cytoplasm, SOD2 (Mn‐SOD), found in the mitochondria, and SOD3, found in the extracellular space. SOD proteins break down (dismutate) ROS, mainly superoxide, into (non‐toxic) oxygen and (less toxic) peroxide. Subsequently, peroxide is decomposed by other enzymes, most notably, catalase. Various mutations in the SOD1 gene directly correlate with the development of familial amyotrophic lateral sclerosis (FALS) through a yet unknown mechanism. Recombinant Human SOD is a 16.8 kDa protein containing 160 amino acid residues including an N-terminal His‐tag.