title: Production of dioxygen in the dark: dismutases of oxyanions.
abstract: O₂-generating reactions are exceedingly rare in biology and difficult to mimic synthetically. Perchlorate-respiring bacteria enzymatically detoxify chlorite (ClO₂(-) ), the end product of the perchlorate (ClO(4)(-) ) respiratory pathway, by rapidly converting it to dioxygen (O₂) and chloride (Cl(-)). This reaction is catalyzed by a heme-containing protein, called chlorite dismutase (Cld), which bears no structural or sequence relationships with known peroxidases or other heme proteins and is part of a large family of proteins with more than one biochemical function. The original assumptions from the 1990s that perchlorate is not a natural product and that perchlorate respiration might be confined to a taxonomically narrow group of species have been called into question, as have the roles of perchlorate respiration and Cld-mediated reactions in the global biogeochemical cycle of chlorine. In this chapter, the chemistry and biochemistry of Cld-mediated O₂generation, as well as the biological and geochemical context of this extraordinary reaction, are described.
authors.affiliation: Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA, jdubois@chemistry.montana.edu.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: DuBois
authors.forename: Sunil
authors.initials: S
authors.lastname: Ojha
mesh_terms: D001419:Bacteria / Q000201:enzymology*; D002104:Cadmium / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism; D007477:Ions / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry / Q000378:metabolism*; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism*; D010472:Perchlorates / Q000378:metabolism*
chemical_list: D002712:Chlorides; D007477:Ions; D010472:Perchlorates; D002104:Cadmium; D010088:Oxidoreductases; C402794:chlorite dismutase; D010100:Oxygen; C494474:perchlorate