Analysis Note

Protein determined by biuret

General description

Formerly E.C. 1.1.3.22

包装

5, 25 units in serum bottle

Unit Definition

One unit will convert 1.0 μmole of xanthine to uric acid per min at pH 7.5 at 25 °C. Approx. 50% of the activity is obtained with hypoxanthine as substrate.

Physical form

Suspension in 2.3 M (NH4)2SO4 containing 1 mM sodium salicylate

Biochem/physiol Actions

Xanthine oxidase is a molybdenum-containing enzyme that is found in the cytosol, and may be strongly inhibited by flavonoids. It plays a vital role in the metabolism of some drugs, as well as purines and pyrimidines.It is also known to be a biological source of reactive oxygen species.

Xanthine oxidase was shown to be involved in the reduction of cytochrome c by the generation of superoxide anions following the oxidation of xanthine. These free radicals are responsible for reducing cytochrome c.