EC Number | Protein Variants | Comment | Organism |
---|---|---|---|
2.4.2.1 | F159Y | site-directed mutagenesis, pre-steadystate chemistry is reduced 32fold in mutant F159Y PNP. Pre-steady-state chemistry compares heavy and light molecular weight wild-type and mutant F159Y PNPs and finds a normal heavy-enzyme isotope effect of 1.31 for wild-type PNP and an inverse effect of 0.75 for F159Y mutant PNP. Increased isotopic mass in F159Y PNP causes more efficient transition state formation. Most heavy enzymes demonstrate normal heavy-enzyme isotope effects, and F159Y PNP is a rare example of an inverse effect | Homo sapiens |
EC Number | KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|---|
2.4.2.1 | additional information | - |
additional information | steady-state Michaelis-Menten kinetics for the light- and heavy-isotope-labeled PNPs are measured for guanosine phosphorolysis, single-turnover pre-steady-state constants. Detailed isotope and kinetic analysis of wild-type an dmutant F159Y mutant enzymes, overview | Homo sapiens | |
2.4.2.1 | 0.0341 | - |
guanosine | pH 7.4, 25°C, wild-type light PNP | Homo sapiens | |
2.4.2.1 | 0.0399 | - |
guanosine | pH 7.4, 25°C, wild-type heavy PNP | Homo sapiens | |
2.4.2.1 | 0.0542 | - |
guanosine | pH 7.4, 25°C, mutant F159Y heavy PNP | Homo sapiens | |
2.4.2.1 | 0.0564 | - |
guanosine | pH 7.4, 25°C, mutant F159Y light PNP | Homo sapiens |
EC Number | Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
2.4.2.1 | guanosine + phosphate | Homo sapiens | - |
guanine + alpha-D-ribose 1-phosphate | - |
r |
EC Number | Organism | UniProt | Comment | Textmining |
---|---|---|---|---|
2.4.2.1 | Homo sapiens | P00491 | - |
- |
EC Number | Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
2.4.2.1 | guanosine + phosphate | - |
Homo sapiens | guanine + alpha-D-ribose 1-phosphate | - |
r |
EC Number | Synonyms | Comment | Organism |
---|---|---|---|
2.4.2.1 | PNP | - |
Homo sapiens |
2.4.2.1 | purine nucleoside phosphorylase | - |
Homo sapiens |
EC Number | Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|---|
2.4.2.1 | 25 | - |
assay at | Homo sapiens |
EC Number | Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|---|
2.4.2.1 | 7.8 | - |
guanosine | pH 7.4, 25°C, wild-type heavy PNP | Homo sapiens | |
2.4.2.1 | 8.3 | - |
guanosine | pH 7.4, 25°C, mutant F159Y heavy PNP | Homo sapiens | |
2.4.2.1 | 8.5 | - |
guanosine | pH 7.4, 25°C, mutant F159Y light PNP | Homo sapiens | |
2.4.2.1 | 8.7 | - |
guanosine | pH 7.4, 25°C, wild-type light PNP | Homo sapiens |
EC Number | pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|---|
2.4.2.1 | 7.4 | - |
assay at | Homo sapiens |
EC Number | General Information | Comment | Organism |
---|---|---|---|
2.4.2.1 | malfunction | human genetic deficiency of PNP impairs expansion of activated T-cells as a consequence of the accumulation of dGTP specifically in activated T-cells. An unbalanced deoxynucleotide triphosphate pool leads to apoptotic cell death in the activated T-cell population, with no effect on quiescent T-cells. The inhibition of PNP is reported to be therapeutic in T-cell lymphoma and gout disease in clinical trials | Homo sapiens |
2.4.2.1 | additional information | crystal structures and TPS dynamics of native and F159Y PNPs explore the catalytic-site geometry associated with these catalytic changes. Experimental validation of transition path-sampling (TPS) predictions for barrier crossing establishes the connection of rapid protein dynamics and vibrational coupling to enzymatic transition state passage | Homo sapiens |
2.4.2.1 | physiological function | enzyme PNP provides the only metabolic pathway for the degradation of 2'-deoxyguanosine in human cells | Homo sapiens |
EC Number | kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|---|
2.4.2.1 | 150.7 | - |
guanosine | pH 7.4, 25°C, mutant F159Y light PNP | Homo sapiens | |
2.4.2.1 | 153.1 | - |
guanosine | pH 7.4, 25°C, mutant F159Y heavy PNP | Homo sapiens | |
2.4.2.1 | 195.5 | - |
guanosine | pH 7.4, 25°C, wild-type heavy PNP | Homo sapiens | |
2.4.2.1 | 255.1 | - |
guanosine | pH 7.4, 25°C, wild-type light PNP | Homo sapiens |