In enzymology, a pyrimidine-nucleoside phosphorylase (EC 2.4.2.2) is an enzyme that catalyzes the chemical reaction
| pyrimidine-nucleoside phosphorylase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 2.4.2.2 | ||||||||
| CAS no. | 9055-35-0 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
- a pyrimidine nucleoside + phosphate a pyrimidine base + alpha-D-ribose 1-phosphate
Thus, the two substrates of this enzyme are pyrimidine nucleoside and phosphate, whereas its two products are pyrimidine base and alpha-D-ribose 1-phosphate.
This enzyme belongs to the family of glycosyltransferases, specifically the pentosyltransferases. The systematic name of this enzyme class is pyrimidine-nucleoside:phosphate alpha-D-ribosyltransferase. This enzyme is also called Py-NPase. This enzyme participates in pyrimidine metabolism.
Structural studies
editAs of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes 1BRW and 2DSJ.
References
edit- Boyer, P.D., Lardy, H. and Myrback, K. (Eds.), The Enzymes, 2nd ed., vol. 5, Academic Press, New York, 1961, p. 237-255.
- Saunders PP, Wilson BA, Saunders GF (1969). "Purification and comparative properties of a pyrimidine nucleoside phosphorylase from Bacillus stearothermophilus". J. Biol. Chem. 244 (13): 3691–7. doi:10.1016/S0021-9258(18)83424-X. PMID 4978445.
- Hamamoto T, Noguchi T, Midorikawa Y (1996). "Purification and characterization of purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase from Bacillus stearothermophilus TH 6-2". Biosci. Biotechnol. Biochem. 60 (7): 1179–80. doi:10.1271/bbb.60.1179. PMID 8782414.
