Metallophosphatases (MPPs), also known as metallophosphoesterases, phosphodiesterases (PDEs), binuclear metallophosphoesterases, and dimetal-containing phosphoesterases (DMPs), represent a diverse superfamily of enzymes with a conserved domain containing an active site consisting of two metal ions (usually manganese, iron, or zinc) coordinated with octahedral geometry by a cage of histidine, aspartate, and asparagine residues. This superfamily includes: the phosphoprotein phosphatases (PPPs), Mre11/SbcD-like exonucleases, Dbr1-like RNA lariat debranching enzymes, YfcE-like phosphodiesterases, purple acid phosphatases (PAPs), YbbF-like UDP-2,3-diacylglucosamine hydrolases, and acid sphingomyelinases (ASMases). The conserved domain is a double beta-sheet sandwich with a di-metal active site made up of residues located at the C-terminal side of the sheets. This domain is thought to allow for productive metal coordination.
Structure:1FJM_A; Oryctolagus cuniculus PP1 binds two Mn2+ ions and microcystin toxin. Two metal ions are positioned by a central beta-alpha-beta-alpha-beta scaffold at the active site.
Comment:The UshA active site is located at the end of a cavity formed at the interface of its two domains. The C-terminal nucleotidase domain also contributes residues to the active site.
Jiyao W et al.(2023). "The conserved domain database in 2023.",