Role of cytochrome b562 in the archaeal aerobic respiratory chain of Sulfolobus sp. strain 7.
The role of cytochrome b562, a fragile constituent of the respiratory terminal oxidase supercomplex of the thermoacidophilic archaeon, Sulfolobus sp. strain 7, was investigated spectroscopically in the membrane-bound state. Cytochrome b562 did not react with CO or cyanide in the membrane-bound state, while it was irreversibly modified to a CO-reactive form (b59) upon solubilization in the presence of cholate and LiCl. Cyanide titration analyses with the succinate-reduced membrane suggested that cytochrome b562 was upstream of both the "gy = 1.89' Rieske FeS cluster and the a-type cytochromes. These results show that the b-type cytochrome functions as an intermediate electron transmitter in the terminal oxidase supercomplex.
Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan.
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Iwasaki
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Oshima
D000332:Aerobiosis; D001426:Bacterial Proteins / Q000502:physiology*; D002248:Carbon Monoxide / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology; D019826:Cholic Acid; D002793:Cholic Acids / Q000494:pharmacology; D003573:Cytochrome b Group / Q000502:physiology*; D029968:Escherichia coli Proteins; D006912:Hydroxyquinolines / Q000494:pharmacology; D018021:Lithium Chloride / Q000494:pharmacology; D010085:Oxidative Phosphorylation / Q000187:drug effects; D012966:Sodium Cyanide / Q000494:pharmacology; D013386:Succinates / Q000494:pharmacology; D019802:Succinic Acid; D016944:Sulfolobus / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D013876:Thiophenes / Q000378:metabolism
D001426:Bacterial Proteins; D002793:Cholic Acids; D003573:Cytochrome b Group; D029968:Escherichia coli Proteins; D006912:Hydroxyquinolines; D013386:Succinates; D013876:Thiophenes; C103358:caldariellaquinol; C001333:2-(n-heptyl)-4-hydroxyquinoline N-oxide; D002248:Carbon Monoxide; C017850:cytochrome b562, E coli; D019802:Succinic Acid; D019826:Cholic Acid; D018021:Lithium Chloride; D012966:Sodium Cyanide