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Author Spotlight: Understanding Microbe Adaptation Using Innovative Techniques for Exploring Thermophilic Evolution
Published on: June 14, 2024
Cytochrome aa3 in facultatively aerobic and hyperthermophilic archaeon Pyrobaculum oguniense
Takuro Nunoura1, Yoshihiko Sako, Takayoshi Wakagi
1Laboratory of Marine Microbiology, Graduate School of Agriculture, Kyoto University, Japan. takuron@jamstec.go.jp
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.
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