BisANS docking with SOD1. BisANS (blue) docked with WT human SOD1 [2C9V] and H46R/H48Q [3GQP]. The zinc loop (aa49-84) is colored green, and electrostatic loop (aa121-144) is colored red. Amino acids 46 and 48 are colored magenta, copper ions (orange), and zinc ions (green). Binding energies are given for bisANS binding sites in kcal/mol. H46R/H48Q possess a binding site for bisANS in the metal binding region, whereas holo WT dimeric SOD1 does not.