Oxidation selective Terms Links

X 10 M s and was 3.1 x 10 M s" at 25°C, pH 7.0 and ionic strength of 1.0 . Kinetic data was interpreted in terms of a mechanism of electron transfer from chromium(II) involving attack of Cr(II) adjacent to the Fe(III) center Analysis of the one-to-one chromium(III) cytochrome c complex revealed that the chromium(III) cross-linked two peptide fragments located in the heme.crevice by binding to tyrosine 67 and asparagine 52 The chromium(III) bound to reduced cytochrome c did not affect the ability of the protein to be reoxidized with ferricyanide and then to be reduced with dithionite . The chromium complex was oxidized by cytochrome oxidase at the same rate as the untreated ferrocytochrome c, however, the rate of reduction of the chromium complex by bovine heart submitochondrial particles was slower than that of untreated ferricytochrome c Thus, the binding of chromium(III) to cytochrome c appears to selectively inhibit its function in certain electron transfer reactions. 

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