title: The role of porcine thyroid peroxidase and FAD-containing monooxygenase in the metabolism of 1-methyl-2-thioimidazole (methimazole).
abstract: The peroxidase and FAD-containing monooxygenase activities of porcine thyroid subcellular preparations were measured and it was observed that FAD-containing monooxygenase activity was considerably lower than that of peroxidase. The end product of 1-methyl-2[14C]thioimidazole oxidation catalysed by thyroid peroxidase was confirmed to be 1-methylimidazole by mass spectrometry. In the presence of thyroid peroxidase 1-methyl-2-thioimidazole would appear initially to be oxidised to bis(1-methylimidazole)-2,2'-disulphide. The extent of oxidation was dependent on the iodide concentration in the reaction mixture.
mesh_terms: D000818:Animals; D007093:Imidazoles / Q000378:metabolism; D007453:Iodide Peroxidase / Q000378:metabolism*; D008713:Methimazole / Q000378:metabolism*; D010105:Oxygenases / Q000378:metabolism*; D010544:Peroxidases / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet; D013552:Swine; D013961:Thyroid Gland / Q000201:enzymology
chemical_list: D007093:Imidazoles; D008713:Methimazole; D010544:Peroxidases; D007453:Iodide Peroxidase; D010105:Oxygenases; C020066:dimethylaniline monooxygenase (N-oxide forming); C018100:1-methylimidazole