deoxyuridine phosphorylase activity
Definition
Target type: molecularfunction
Catalysis of the reaction: 2'-deoxyuridine + phosphate = 2-deoxy-alpha-D-ribose 1-phosphate + uracil. [RHEA:22824]
Deoxyuridine phosphorylase (dUrdPase) is an enzyme that catalyzes the reversible phosphorolysis of deoxyuridine (dUrd) to uracil and deoxyribose-1-phosphate. This reaction is essential for the salvage pathway of pyrimidine nucleotide biosynthesis. dUrdPase plays a critical role in maintaining the balance of deoxynucleotides, which are necessary for DNA replication and repair. It removes deoxyuridine, a potential mutagenic precursor to thymine, from the nucleotide pool. The enzyme is highly specific for deoxyuridine, exhibiting little activity with other pyrimidine nucleosides. The mechanism involves the formation of a covalent intermediate between the enzyme and the substrate, followed by nucleophilic attack of phosphate on the glycosidic bond, resulting in the release of uracil and deoxyribose-1-phosphate. dUrdPase activity is regulated by a number of factors, including substrate concentration, pH, and the presence of inhibitors. The enzyme is found in a variety of organisms, including bacteria, fungi, and mammals. In humans, dUrdPase is encoded by the DUT gene and plays a critical role in DNA repair and replication. Deficiency of dUrdPase activity can lead to increased levels of deoxyuridine in cells, which can result in DNA damage and mutations. This can contribute to the development of various diseases, including cancer.'
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Proteins (1)
| Protein | Definition | Taxonomy |
|---|---|---|
| Uridine phosphorylase 1 | A uridine phosphorylase 1 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q16831] | Homo sapiens (human) |
Compounds (4)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| doxifluridine | doxifluridine : A pyrimidine 5'-deoxyribonucleoside that is 5-fluorouridine in which the hydroxy group at the 5' position is replaced by a hydrogen. It is an oral prodrug of the antineoplastic agent 5-fluorouracil. Designed to circumvent the rapid degradation of 5-fluorouracil by dihydropyrimidine dehydrogenase in the gut wall, it is converted into 5-fluorouracil in the presence of pyrimidine nucleoside phosphorylase. | organofluorine compound; pyrimidine 5'-deoxyribonucleoside | antimetabolite; antineoplastic agent; prodrug |
| 5-benzylacyclouridine | 5-benzyl-1-(2-hydroxyethoxymethyl)uracil : A pyrimidone that is uracil which is substituted by a 2-hydroxyethoxymethyl group at position 1 and a benzyl group at position 5. 5-benzylacyclouridine: structure given in first source | hydroxyether; primary alcohol; pyrimidone | |
| 3-cyano-6-hydroxy-4-methyl-2-pyridone | 3-cyano-6-hydroxy-4-methyl-2-pyridone: structure in first source | ||
| 2,6-dihydroxy-3-cyanopyridine | 2,6-dihydroxy-3-cyanopyridine: inhibitor of 5-fluorouracil degradation |