title: Selenite binding to carbon monoxide oxidase from Pseudomonas carboxydovorans. Selenium binds covalently to the protein and activates specifically the CO----methylene blue reaction.
abstract: The CO----methylene blue and CO----dichlorophenol indophenol activities of carbon monoxide oxidase were specifically activated upon aerobic incubation with selenite, whereas the NADH----methylene blue activity was not altered. Fully active enzyme contained selenium, molybdenum, and flavin adenine dinucleotide in a 1:1:1 ratio. Selenium was covalently bound to the protein, probably between the sulfurs of half-cystine residues, and not a constituent of the molybdenum cofactor. The action of selenite was directed to the cytoplasmic species of carbon monoxide oxidase exclusively, whereas the CO----methylene blue activity of the membrane-bound enzyme remained unaffected.
mesh_terms: D000445:Aldehyde Oxidoreductases / Q000378:metabolism*; D004789:Enzyme Activation; D007700:Kinetics; D008751:Methylene Blue; D011485:Protein Binding; D011549:Pseudomonas / Q000201:enzymology*; D020887:Selenious Acid; D012643:Selenium / Q000494:pharmacology*
chemical_list: D000445:Aldehyde Oxidoreductases; C033598:carbon monoxide-methylene blue oxidoreductase; D020887:Selenious Acid; D012643:Selenium; D008751:Methylene Blue