PURIFICATION OF XANTHINE DEHYDROGENASE AND SULFITE OXIDASE FROM CHICKEN LIVER

Xanthine dehydrogenase and sulfite oxidase from chicken liver are oxom olybdenum enzymes which catalyze the oxidation of xanthine to uric aci d and sulfite to sulfate, respectively. Independent purification proto cols have been previously described for both enzymes. Here we describe a procedure by which xanthine dehydrogenase and sulfite oxidase are p urified simultaneously from the same batch of fresh chicken liver. Als o, unlike the protocols described earlier, this procedure avoids the u se of acetone extraction as well as a heat step, thus minimizing damag e to the molybdenum centers of the enzymes.