Oxidoreduction biological

Figure 3. The four questions in flavin-dependent biological oxidoreduction mechanisms...

At the end of this review, it is worthwhile surveying asymmetric organic reactions mediated by an enzyme in which a biological material is used as one of the chemical reagents for an organic reaction. Oxidoreduction mediated by an microorganism was reviewed recently by Sih and Chen (1984) and the reader is recommended to consult that review for this particular topic. 

In chemistry, an oxidoreduction can also be achieved by the transfer of a hydrogen atom (not a hydrogen ion, IF ). Such a transfer also involves a movement of electrons. Biological oxidations often involve dehydrogenation. 

Clearly, no hydride transfer is involved, only proton shifts via the formation of a covalent intermediate at position 4a. Hamilton argues that biological oxidoreduction (dehydration) reactions rarely, if at all, involve hydride ions because protons are not shielded by electrons and thus travel much faster and more efficiently in biological media (279). 

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