Any feedback?
Literature summary for 2.4.2.4 extracted from
- Kinetics mechanism and regulation of native human hepatic thymidine phosphorylase (2019), Int. J. Biochem. Cell Biol., 110, 122-129 .
Activating Compound
| Activating Compound | Comment | Organism | Structure |
|---|---|---|---|
| 2-deoxy-alpha-D-ribose 1-phosphate | dRib-1-P , a noncompetitive product inhibitor of the forward reaction, in the reverse reaction, dRib-1-P enhanced the binding of thymine | Homo sapiens |  |
| thymine | thymine is a product activator, but becomes a substrate inhibitor at concentrations eight times higher than its Km. Competitive substrate inhibition at high concentration for the human liver TP | Homo sapiens | |
Inhibitors
| Inhibitors | Comment | Organism | Structure |
|---|---|---|---|
| 2-deoxy-alpha-D-ribose 1-phosphate | dRib-1-P , a non-competitive product inhibitor of the forward reaction, in the reverse reaction, dRib-1-P enhanced the binding of thymine | Homo sapiens | |
| 2-deoxy-alpha-D-ribose 1-phosphate | dRib-1-P is a competitive product inhibitor of the forward reaction, in the reverse reaction, dRib-1-P enhances the binding of thymine | Mus musculus | |
| thymidine | yields a non-competitive inhibition pattern in agreement with a random mechanism | Homo sapiens | |
| thymine | thymine is a product activator, but becomes a substrate inhibitor at concentrations eight times higher than its Km. Thymine is an effector rather than a product inhibitor | Homo sapiens | |
| thymine | thymine is a product activator, but becomes a competitive inhibitor at concentrations eight times higher than its Km | Mus musculus | |
KM Value [mM]
| KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
|---|---|---|---|---|---|
| additional information | - |
additional information | kinetic mechanism and regulation of native human hepatic thymidine phosphorylase (TP), kinetics | Homo sapiens | |
| 0.0058 | - |
phosphate | pH 7.5, 37°C | Homo sapiens | |
| 0.09 | - |
2-deoxy-alpha-D-ribose 1-phosphate | pH 7.5, 37°C | Homo sapiens | |
| 0.244 | - |
thymine | pH 7.5, 37°C | Homo sapiens | |
| 0.284 | - |
thymidine | pH 7.5, 37°C | Homo sapiens | |
Natural Substrates/ Products (Substrates)
| Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
|---|---|---|---|---|---|---|
| thymidine + phosphate | Homo sapiens | - |
thymine + 2-deoxy-alpha-D-ribose 1-phosphate | - |
r | |
| thymidine + phosphate | Mus musculus | - |
thymine + 2-deoxy-alpha-D-ribose 1-phosphate | - |
r | |
Organism
| Organism | UniProt | Comment | Textmining |
|---|---|---|---|
| Homo sapiens | P19971 | - |
- |
| Mus musculus | Q99N42 | - |
- |
Reaction
| Reaction | Comment | Organism | Reaction ID |
|---|---|---|---|
| thymidine + phosphate = thymine + 2-deoxy-alpha-D-ribose 1-phosphate | sequential random bi-bi mechanism | Homo sapiens | |
| thymidine + phosphate = thymine + 2-deoxy-alpha-D-ribose 1-phosphate | sequential random bi-bi mechanism | Mus musculus |
Source Tissue
| Source Tissue | Comment | Organism | Textmining |
|---|---|---|---|
| liver | - |
Homo sapiens | - |
Substrates and Products (Substrate)
| Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
|---|---|---|---|---|---|---|
| additional information | initial velocity studies showed an intersecting pattern, consistent with substrate-enzyme-co-substrate complex formation, and a binding pattern indicating that the binding of the substrate interferes with the binding of the co-substrate and vice versa | Homo sapiens | ? | - |
- |
|
| thymidine + phosphate | - |
Homo sapiens | thymine + 2-deoxy-alpha-D-ribose 1-phosphate | - |
r | |
| thymidine + phosphate | - |
Mus musculus | thymine + 2-deoxy-alpha-D-ribose 1-phosphate | - |
r | |
| thymine + 2-deoxy-alpha-D-ribose 1-phosphate | - |
Homo sapiens | thymidine + phosphate | - |
r | |
| thymine + 2-deoxy-alpha-D-ribose 1-phosphate | - |
Mus musculus | thymidine + phosphate | - |
r | |
Temperature Optimum [°C]
| Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
|---|---|---|---|
| 37 | - |
assay at | Homo sapiens |
pH Optimum
| pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
|---|---|---|---|
| 5 | 8.5 | thymidine phosphorolysis | Homo sapiens |
| 7.5 | - |
thymidine synthesis | Homo sapiens |
pH Range
| pH Minimum | pH Maximum | Comment | Organism |
|---|---|---|---|
| 5 | 9 | activity range of synthesis of thymidine, profile overview | Homo sapiens |
| 5 | 11 | activity range of phosphorolysis of thymidine, profile overview | Homo sapiens |
Ki Value [mM]
| Ki Value [mM] | Ki Value maximum [mM] | Inhibitor | Comment | Organism | Structure |
|---|---|---|---|---|---|
| additional information | - |
additional information | inhibition kinetics | Homo sapiens | |
| additional information | - |
additional information | inhibition kinetics | Mus musculus |
General Information
| General Information | Comment | Organism |
|---|---|---|
| physiological function | thymidine phosphorylase (TP) catalyzes the reversible phosphorolysis of thymidine, deoxyuridine, and their analogues to their respective nucleobases and 2-deoxy-alpha-D-ribose-1-phosphate. TP is a key enzyme in the pyrimidine salvage pathways. Activity of the enzyme is crucial in angiogenesis, cancer chemotherapy, radiotherapy, and tumor imaging | Homo sapiens |
Use of this online version of BRENDA is free under the CC BY 4.0 license. See terms of use for full details.
Release 2023.1 (January 2023)
Legal
Curated at
Member of
