KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | kinetic analysis, Michaelis-Menten model, detailed overview. Binding of a 6-formylpterin at one of the two xanthine oxidase active sites slows down the turnover rate of xanthine at the adjacent active site and converts the V-[S] plot from substrate inhibition kinetic pattern to a classical Michaelis-Menten hyperbolic saturation pattern. In contrast, binding of xanthine at an active site accelerates the turnover rate of 6-formylpterin at the neighboring active site | Bos taurus |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
extracellular | - |
Bos taurus | - |
- |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Fe2+ | two 2Fe-2S clusters. The Mo(VI) ion at the active site is reduced to Mo(IV), which then transfers two electrons, via the 2Fe-2S clusters, to the FAD cofactor | Bos taurus | |
Mo4+ | the Mo(VI) ion at the active site is reduced to Mo(IV), which then transfers two electrons, via the 2Fe-2S clusters, to the FAD cofactor | Bos taurus |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
290000 | - |
- |
Bos taurus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
xanthine + H2O + O2 | Bos taurus | - |
urate + H2O2 | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Bos taurus | - |
- |
- |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
commercial preparation | - |
Bos taurus | - |
milk | - |
Bos taurus | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
2-amino-4-hydroxypterin + H2O + O2 | substrate inhibition kinetic pattern | Bos taurus | ? + H2O2 | - |
? | |
6-formylpterin + H2O + O2 | - |
Bos taurus | ? + H2O2 | - |
? | |
adenine + H2O + O2 | substrate inhibition kinetic pattern | Bos taurus | ? + H2O2 | - |
? | |
lumazine + H2O + O2 | classical Michaelis-Menten hyperbolic saturation kinetic pattern | Bos taurus | ? + H2O2 | - |
? | |
xanthine + H2O + O2 | - |
Bos taurus | urate + H2O2 | - |
? | |
xanthine + H2O + O2 | substrate inhibition kinetic pattern | Bos taurus | urate + H2O2 | - |
? | |
xanthopterin + H2O + O2 | substrate activation kinetic pattern | Bos taurus | ? + H2O2 | - |
? |
Subunits | Comment | Organism |
---|---|---|
homodimer | - |
Bos taurus |
Synonyms | Comment | Organism |
---|---|---|
XOD | - |
Bos taurus |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
22 | - |
assay at | Bos taurus |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Bos taurus |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
FAD | the Mo(VI) ion at the active site is reduced to Mo(IV), which then transfers two electrons, via the 2Fe-2S clusters, to the FAD cofactor | Bos taurus | |
additional information | the enzyme contains two 2Fe-2S clusters | Bos taurus |
General Information | Comment | Organism |
---|---|---|
additional information | the enzyme is regulated by substrates at active sites via cooperative interactions between catalytic subunits. A substrate can regulate the activity of xanthine oxidase via binding at the active sites, or a xanthine oxidase catalytic subunit can simultaneously serve as a regulatory unit | Bos taurus |