title: Oxygen activation by mononuclear Mn, Co, and Ni centers in biology and synthetic complexes.
abstract: The active sites of metalloenzymes that catalyze O2-dependent reactions generally contain iron or copper ions. However, several enzymes are capable of activating O2at manganese or nickel centers instead, and a handful of dioxygenases exhibit activity when substituted with cobalt. This minireview summarizes the catalytic properties of oxygenases and oxidases with mononuclear Mn, Co, or Ni active sites, including oxalate-degrading oxidases, catechol dioxygenases, and quercetin dioxygenase. In addition, recent developments in the O2reactivity of synthetic Mn, Co, or Ni complexes are described, with an emphasis on the nature of reactive intermediates featuring superoxo-, peroxo-, or oxo-ligands. Collectively, the biochemical and synthetic studies discussed herein reveal the possibilities and limitations of O2activation at these three "overlooked" metals.
authors.affiliation: Department of Chemistry, Marquette University, Milwaukee, WI, 53201, USA. adam.fiedler@marquette.edu.
authors.forename: Adam T
authors.initials: AT
authors.lastname: Fiedler
authors.affiliation: Department of Chemistry, Marquette University, Milwaukee, WI, 53201, USA.
authors.forename: Anne A
authors.initials: AA
authors.lastname: Fischer
mesh_terms: D003035:Cobalt / Q000378:metabolism*; D004798:Enzymes / Q000378:metabolism; D006801:Humans; D008345:Manganese / Q000378:metabolism*; D009532:Nickel / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*
chemical_list: D004798:Enzymes; D003035:Cobalt; D008345:Manganese; D009532:Nickel; D010100:Oxygen
keywords: Cobalt; Dioxygen activation; Manganese; Metalloenzymes; Model complexes; Nickel