Reduction by Dithionite Ion of Adducts of Metmyoglobin

نویسنده

  • RALPH G. WILKINS
چکیده

The rate and equilibrium constants for the formation of a number of metmyoglobin species Mb+X (X = imidazole, imidazole-H-, 1-methylimidazole, 2-methylimidazole, 4-6 troimidazole, 2-methyl-5-nitroimidazole, pyridine, 2-, 3-, and 4-picoline) and the rates of their reduction by dithionite have been measured at 25”. Several different kinds of kinetic behavior for the reduction were observed. In all cases, a rate constant for direct reaction of Mb+X with SO*can be assessed. The data strongly support attack of SO,on the ligand, followed by electron transfer through the n system to the metal ion.

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تاریخ انتشار 2002