Merck, 10110434001, Xanthine Oxidase (XOD)

General description
Xanthine:oxygen oxidoreductase
Xanthine Oxidase (XOD) is a metal flavoprotein. It has FAD, molybdenum and iron in the ratio 2:2:8.
Application
Xanthine Oxidase has been used to study tyrosine nitration.
Xanthine Oxidase (XOD) has been used in the assessment of XOR-mediated NO production from NDHP and assessment of nitrite-derived NO in liver and purified XOR.
Biochem/physiol Actions
Xanthine Oxidase (XOD) exhibits a broad substrate specificity including aldehydes, purines and pteridines. Furthermore, this enzyme reduces oxygen to generate superoxide, hydrogen peroxide and reactive oxygen species (ROS). It also reduces nitrite to yield reactive nitrogen species (RNS), such as peroxynitrite and nitric oxide. Owing to its ability to generate RNS and ROS, XOD might play an important role as an antimicrobial agent in the neonatal gut, thereby complementing endogenous enzyme of the intestinal epithelium.
Physical form
Suspension in 3.2 M ammonium sulfate solution, 10 mM EDTA, pH approximately 8
Preparation Note
Activator: O₂
Stabilizers: The substance is stabilized by the addition of EDTA; salicylate is not added.
Analysis Note
Contaminants: <0.005% guanase, NP and uricase, each, <0.05% ADA, <0.05% alkaline phosphatase (4-nitrophenyl phosphate as the substrate)
Note: Chromatographically purified.
Other Notes
For life science research only. Not for use in diagnostic procedures.
One unit (U) xanthine oxidase will produce 1 μmol of uric acid (E₂₉₃nm = 12.2 mmol⁻¹ x L x cm⁻¹) from the oxidation of 1 μmol of xanthine in 1 min at 25 °C and pH8.5.
XOD is a dimer. Each subunit contains 1 atom of molybdenum, 2 iron-sulfur centers (non-heme iron, ferredoxin-type) and 1 molecule of FAD.