Myoglobin mutant reactions

With ferryl myoglobin, in contrast to peroxidases, the reactions of the protein free radicals and that of the ferryl haem can be considered as uncoupled from each other. The protein has not been designed to form a cation radical for a specific reaction therefore not only is more than one cation free radical generated, but there is no control over their subsequent reactions. A similar situation can be observed in cytochrome c peroxidase mutants that have lost tryptophan-191. A different amino-acid free radical is still formed that is less stable. Indeed, even in the presence of tryptophan-191, small amounts of other free radicals are formed [237] this is further evidence that even in enzymes it is difficult to exclusively control free radical reactions. 

J Mutant spermwhale myoglobin with E7 His — Gly mutation. 1 Major component of heterogeneous reaction. 

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