Xanthine Oxidase

The enzyme xanthine oxidase, or XO, (bovine milk enzyme is PDB 1FIQ, EC 1.1.3.32) catalyzes the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthine to uric acid: Jump to: navigation, search Image File history File links XanthineOxidase-1FIQ.png Gen w/ Deepview from PDB:1FIQ File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Jump to: navigation, search Image File history File links XanthineOxidase-1FIQ.png Gen w/ Deepview from PDB:1FIQ File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Ribbon diagram of the catalytically perfect enzyme TIM. Factor D enzyme crystal prevents the immune system from inappropriately running out of control. ... The Protein Data Bank (PDB) is a repository for 3-D structural data of proteins and nucleic acids. ... EC numbers (Enzyme Commission numbers) are a numerical classification scheme for enzymes, based on the chemical reactions they catalyze. ... The most fundamental reactions in chemistry are the redox processes. ... Hypoxanthine is a naturally occurring purine derivative, and one of the products of the action of xanthine oxidase on xanthine, though more normally in purine degradation, hypoxanthine is oxidized by xanthine oxidase to form xanthine. ... Xanthines are a group of alkaloids that are commonly used for their effects as mild stimulants and as bronchodilators, notably in treating the symptoms of asthma. ... Uric acid is a minor end-product of nitrogen metabolism in the human body (the main product being urea), and is found in small amounts in urine. ...

• hypoxanthine + O₂ <-> xanthine + H₂O₂
• xanthine + O₂ + 2H₂O <-> uric acid + 2H₂O₂

The protein is large, having a molecular weight of 270,000, and has 2 flavin molecules (bound as FAD), 2 molybdenum atoms, and 8 iron atoms bound per enzymatic unit. The molecular mass of a substance (less accurately called molecular weight and abbreviated as MW) is the mass of one molecule of that substance, relative to the unified atomic mass unit u (equal to 1/12 the mass of one atom of carbon-12). ... Flavin is also the name of a commune in the Aveyron département, in France Flavin adenine dinucleotide (FAD), upper, reduced FAD (FADH2), lower Flavin is a tricyclic heteronuclear organic ring whose biochemical source is the vitamin riboflavin. ... General Name, Symbol, Number molybdenum, Mo, 42 Chemical series transition metals Group, Period, Block 6, 5, d Appearance gray metallic Atomic mass 95. ... Jump to: navigation, search General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Atomic mass 55. ...

In humans, xanthine oxidase is normally found in the liver and not free in the blood. During severe liver damage, xanthine oxidase is released into the blood, so a blood assay for XO is a way to determine if liver damage has happened. As well, because xanthine oxidase is a metabolic pathway for uric acid formation, the xanthine oxidase inhibitor allopurinol is used in the treatment of gout. The liver is an organ in vertebrates, including humans. ... The liver is an organ in vertebrates, including humans. ... In biochemistry, a metabolic pathway is a series of chemical reactions occurring within a cell, catalyzed by enzymes, to achieve in either the formation of a metabolic product to be used or stored by the cell, or the initiation of another metabolic pathway (then called a flux generating step). ... Uric acid is a minor end-product of nitrogen metabolism in the human body (the main product being urea), and is found in small amounts in urine. ... Allopurinol is a drug used for the treatment of gout. ...

Xanthinuria is a rare genetic disorder where the lack of xanthine oxidase leads to high concentration of xanthine in blood and can cause health problems such as renal failure. There is no specific treatment, sufferers are advised by doctors to avoid foods high in purine and to maintain a high fluid intake. Jump to: navigation, search Xanthines are a group of alkaloids that are commonly used for their effects as mild stimulants and as bronchodilators, notably in treating the symptoms of asthma. ... A genetic disorder, or genetic disease is a disease caused by abnormal expression of one or more genes in a person causing a clinical phenotype. ... Renal failure is the condition where the kidneys fail to function properly. ... Purine is a heterocyclic aromatic organic compound, consisting of a pyrimidine ring fused to an imidazole ring. ...

See also

• sodium molybdate