EC Number   |
General Information |
Reference |
|---|
    2.4.2.1 | evolution |
in some organisms, like Escherichia coli, two distinct forms of PNP exist, with markedly different structure and substrate specificity. The second form, the so-called E. coli PNP-II, is sometimes referred to as xanthosine phosphorylase, since it is inducible by this nucleoside, but its specificity is not limited to this compound, and includes guanosine, inosine and nicotinamide riboside |
759101 |
| 2.4.2.1 | evolution |
in some organisms, like Escherichia coli, two distinct forms of PNP exist, with markedly different structure and substrate specificity. The second form, the so-called Escherichia coli PNP-II, is sometimes referred to as xanthosine phosphorylase, since it is inducible by this nucleoside, but its specificity is not limited to this compound, and includes guanosine, inosine and nicotinamide riboside |
759101 |
| 2.4.2.1 | evolution |
most PNPs are divided into trimeric PNPs and hexametric PNPs based on molecular mass, protein structure, or substrate specificity |
-, 759810 |
| 2.4.2.1 | evolution |
the enzyme belongs to the type I PNP family of hexameric enzymes |
758600 |
| 2.4.2.1 | evolution |
the homodimeric PNP from Ervinia carotovora cannot be assigned to the two described PNP classes, trimeric and hexameric PNPs |
759101 |
| 2.4.2.1 | evolution |
the homotetrameric PNP from Baccilus cereus cannot be assigned to the two described PNP classes, trimeric and hexameric PNPs |
759101 |
| 2.4.2.1 | evolution |
the pentameric PNP from Plasmodium lophurae cannot be assigned to the two described PNP classes, trimeric and hexameric PNPs |
759101 |
| 2.4.2.1 | evolution |
the PNP from Cellulomonas sp. cannot be assigned to the any of two described PNP classes, trimeric and hexameric PNPs |
759101 |
| 2.4.2.1 | evolution |
the PNP from Thermus thermophilus cannot be assigned to the any of two described PNP classes, trimeric and hexameric PNPs |
759101 |
| 2.4.2.1 | malfunction |
effect of remote mutations on the thermodynamic activation parameters of human purine nucleoside phosphorylase, overview. More than 2700 independent reaction free energy profiles for six different temperatures are calculated to obtain high-precision computational Arrhenius plots. On the basis of these, the activation enthalpies and entropies are computed from linear regression of the plots with DELTAG++ as a function of 1/T to obtain thermodynamic activation parameters. The substrate specificity is related to the difference in thermodynamic activation parameters. Remote mutations affect the activation enthalpy-entropy balance |
758797 |
