title: Cytochrome aa3 in facultatively aerobic and hyperthermophilic archaeon Pyrobaculum oguniense.
abstract: We partially purified and characterized the cytochrome aa3 from the facultatively aerobic and hyperthermophilic archaeon Pyrobaculum oguniense. This cytochrome aa3 showed oxygen consumption activity with N, N, N', N'-tetramethyl-1,4-phenylenediamine and ascorbate as substrates, and also displayed bovine cytochrome c oxidase activity. These enzymatic activities of cytochrome aa3 were inhibited by cyanide and azide. This cytochrome contained heme As, but not typical heme A. An analysis of trypsin-digested fragments indicated that 1 subunit of this cytochrome was identical to the gene product of subunit I of the SoxM-type heme--copper oxidase (poxC). This is the first report of a terminal oxidase in hyperthermophilic crenarchaeon belonging to the order Thermoproteales.
authors.affiliation: Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Japan. takuron@jamstec.go.jp
authors.forename: Takuro
authors.initials: T
authors.lastname: Nunoura
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Sako
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Wakagi
authors.forename: Aritsune
authors.initials: A
authors.lastname: Uchida
mesh_terms: D000332:Aerobiosis; D000818:Animals; D019843:Archaeal Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006418:Heme / Q000378:metabolism; D006358:Hot Temperature; D010088:Oxidoreductases; D010101:Oxygen Consumption; D041543:Pyrobaculum / Q000201:enzymology* / Q000502:physiology
chemical_list: D019843:Archaeal Proteins; D006418:Heme; D010088:Oxidoreductases; C024748:copper oxidase; D003576:Electron Transport Complex IV