Cytochrome production with camphor substrate

The understanding of the degradation of natural products such as camphor has been greatly enhanced by understanding the catalytic cycle of the cytochrome P-450 enzyme P-450cam in structural detail.3,4 These enzymes catalyze the addition of 02 to nonactivated hydrocarbons at room temperatures and pressures - a reaction that requires high temperature to proceed in the absence of a catalyst. O-Methyltransferases are central to the secondary metabolic pathway of phenylpropanoid biosynthesis. The structural basis of the diverse substrate specificities of such enzymes has been studied by solving the crystal structures of chalcone O-methyltransferase and isoflavone O-methyltransferase complexed with the reaction products.5 Structures of these and other enzymes are obviously important for the development of biomimetic and thus environmentally more friendly approaches to natural product synthesis. 

Cytochrome P-450 Catalyzed Reactions - Studies with 02 have established that the cytochrome P-450 mediated hydroxylation of camphor by the bacterial enzyme and the enzyme purified from rat liver results in the incorporation of atmospheric oxygen in the 5-exo-hydroxylation product. Cumene [ 02]hydroperoxide will transfer its peripheral oxygen atom to a variety of compounds which serve as substrates for mammalian cytochrome P-450. As expected, 02 served as the oxygen source for the bacterial cytochrome P-450 catalyzed epoxidation of 5,6-dehydrocamphor.N-Hydroxy-methylcarbazole, formed by the cytochrome P-450 catalyzed oxidation of N-raethylcarbazole, incorporates 0 exclusively from dioxygen. Under anaerobic conditions cytochrome P-450 may catalyze the intramolecular transfer of oxygen present in tertiary amine N-oxides. Mechanistic studies on S-dealkylation and S-oxidation reactions also have used tracer methods. ... 

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