Soluble Cytochromes as Electron-transfer Mediators

Cytochromes, particularly cytochrome c (Cytc), are small heme-containing redox 

Reductive biocatalytic transformations mediated by Cyt c have been exemplified in a variety of following systems. Cytc electrochemically reduced at a promoter-modified electrode surface has mediated the electron-transfer to soluble laccase (from Coriolus hirsutus), which biocatalyzed the reduction of O2 to water [320]. 

Oxidative biocatalytic processes mediated by Cyt c have been exemplified in several systems. The electrochemical oxidation of Cyt c has been coupled to lactate dehydrogenase, which catalyzes the oxidation of L-lactate [323]. Similar electron transport was also provided by ferrocene mono-carboxylic acid mediating the electron-transfer from lactate dehydrogenase to the electrode. Although the rate constants for electron-transfer between lactate dehydrogenase and Cyt c- and ferrocene-mediators are similar (6.7 x 10 s  

Cytc mediation process is much more specific and is not affected by any inter-ferant that is not recognized by Cyt c. The specificity of this mediation process can be further utilized to provide regeneration of NADP+, which can be connected 

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