Pyrimidine-nucleoside phosphorylase
| Pyrimidine-nucleoside phosphorylase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 2.4.2.2 | ||||||||
| CAS no. | 9055-35-0 | ||||||||
| Databases | |||||||||
| BRENDA | enzyme data | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | enzyme entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| Rhea | reactions | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
Pyrimidine-nucleoside phosphorylase (EC 2.4.2.2) is an enzyme that catalyzes several phosphorolysis reactions which convert a pyrimidine nucleoside into the corresponding pyrimidine, by cleavage of the α-D-ribose 1-phosphate sugar unit:[1]
- a pyrimidine nucleoside + phosphate (Pi) α-D-ribose 1-phosphate + a pyrimidine base
For example, uridine gives uracil:
The reaction is reversible, so this is also how the pyrimidine nucleosides uridine, cytidine, 2'-deoxyuridine, and thymidine can be made in the bacterium Bacillus stearothermophilus in which the enzyme was characterised.[2][3][4] It has also been described from Enterobacter aerogenes.[5]
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.[6]
Structural studies
As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes PDB: 1BRW and PDB: 2DSJ.[7]
References
- ↑ Boyer, P.D., Lardy, H. and Myrback, K. (Eds.), The Enzymes, 2nd ed., vol. 5, Academic Press, New York, 1961, p. 237-255.
- ↑ Saunders, P. P.; Wilson, B. A.; Saunders, G. F. (1969). "Purification and Comparative Properties of a Pyrimidine Nucleoside Phosphorylase from Bacillus stearothermophilus". Journal of Biological Chemistry. 244 (13): 3691–3697. doi:10.1016/S0021-9258(18)83424-X. PMID 4978445.
- ↑ Tomoki, Hamamoto; Toshitada, Noguchi; Yuichiro, Midorikawa (1996). "Purification and Characterization of Purine Nucleoside Phosphorylase and Pyrimidine Nucleoside Phosphorylase from Bacillus stearothermophilus TH 6-2". Bioscience, Biotechnology, and Biochemistry. 60 (7): 1179–1180. doi:10.1271/bbb.60.1179. PMID 8782414.
- ↑ Okuyama, Kiyoshi; Hamamoto, Tomoki; Noguchi, Toshitada; Midorikawa, Yuichiro (1996). "Molecular Cloning and Expression of the Pyrimidine Nucleoside Phosphorylase Gene from Bacillus stearothermophilus TH 6–2". Bioscience, Biotechnology, and Biochemistry. 60 (10): 1655–1659. doi:10.1271/bbb.60.1655. PMID 8987664.
- ↑ Wei, Xiao-kun; Ding, Qing-bao; Zhang, Lu; Guo, Yong-li; Ou, Lin; Wang, Chang-lu (2008). "Induction of nucleoside phosphorylase in Enterobacter aerogenes and enzymatic synthesis of adenine arabinoside". Journal of Zhejiang University Science B. 9 (7): 520–526. doi:10.1631/jzus.B0710618. PMC 2443347. PMID 18600781.
- ↑ Enzyme 2.4.2.2 at KEGG Pathway Database.
- ↑ Pugmire, Matthew J.; Ealick, Steven E. (1998). "The crystal structure of pyrimidine nucleoside phosphorylase in a closed conformation". Structure. 6 (11): 1467–1479. doi:10.1016/S0969-2126(98)00145-2. PMID 9817849.