Cofactor Substitution In Vitro

Peroxides that directly convert the heme iron of P450s to a ferric hydroperoxy complex by the peroxide shunf (e.g., hydrogen peroxide, cumene peroxide, or tert-butyl oxide) could be useful for oxidation of various substrates. The essential problem in utilizing the peroxide shunf for P450 biocatalysis seems to lie in the time-dependent degradation of the heme and in oxidation of the protein [169, 170]. Methods of directed evolution, tike random and site-specific mutagenesis, were applied to evolve P450s to enhance the efficiency of the peroxide shunt pathway [171]. 

Electrochemical reduction of P450s by using an electrode seems to be the most convenient way of fabricating bioreactors [172] and has been studied in detail for more than 15 years. However, heme reduction on a cathode is comphcated and most 

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