Probing a Plausible Mechanistic and Stable Intermediate Route in Oxidative Hydroxylation of Formamideby Xanthine Oxidase.
Abstract
The most physiological importance of xanthine oxidase enzyme is to catalyze oxidation of hypoxanthine to xanthine, subsequently xanthine to uric acid in the final steps of purine degradation. Thus, probing a plausible mechanistic route for the hydroxylation process is the first aim in designing a drug. However, to probe the mechanistic route the stable intermediate route were understood. The study of electronic calculation of molybdenum comprising enzyme complex xanthine oxidase with formamide has been approved out using density functional theory calculations. The electronic structure calculations were carried out on a model consisting truncated XO active site in Mo(VI), Mo(V) and Mo(IV) oxidation state covalently bonded to substrate carbon via an oxygen bridge, Mo-OCRH. According to the computation data, the oxidation of formamide was found to give nitrogen containing carbamate intermediate and formate intermediate. However, the two pathways proposed for the oxidation of formamide through either carbamate or formate intermediate was not yet known. Our calculation results indicate that, in oxidation process of formamide the carbamate intermediate is thermodynamically more stable than formate intermediate. KEY WORDS: Xanthine Oxidase, Formate, CarbamateandMolybdenumReferences
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