Biology:Adenosylhomocysteine nucleosidase
| adenosylhomocysteine nucleosidase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC number | 3.2.2.9 | ||||||||
| CAS number | 9055-10-1 | ||||||||
| 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 | ||||||||
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In enzymology, an adenosylhomocysteine nucleosidase (EC 3.2.2.9) is an enzyme that catalyzes the chemical reaction
- S-adenosyl-L-homocysteine + H2O [math]\displaystyle{ \rightleftharpoons }[/math] S-(5-deoxy-D-ribos-5-yl)-L-homocysteine + adenine
Thus, the two substrates of this enzyme are S-adenosyl-L-homocysteine and H2O, whereas its two products are S-(5-deoxy-D-ribos-5-yl)-L-homocysteine and adenine.
This enzyme belongs to the family of hydrolases, specifically those glycosylases that hydrolyse N-glycosyl compounds. The systematic name of this enzyme class is S-adenosyl-L-homocysteine homocysteinylribohydrolase. Other names in common use include S-adenosylhomocysteine hydrolase (ambiguous), S-adenosylhomocysteine nucleosidase, 5'-methyladenosine nucleosidase, S-adenosylhomocysteine/5'-methylthioadenosine nucleosidase, and AdoHcy/MTA nucleosidase. This enzyme participates in methionine metabolism.
Structural studies
As of late 2007, 8 structures have been solved for this class of enzymes, with PDB accession codes 1JYS, 1NC1, 1NC3, 1Y6Q, 1Y6R, 1Z5N, 1Z5O, and 1Z5P.
References
- Duerre JA (1962). "A hydrolytic nucleosidase acting on S-adenosylhomocysteine and on 5-methylthioadenosine". J. Biol. Chem. 237: 3737–3741.
- "Kinetic properties and the effect of substrate analogues on 5'-methylthioadenosine nucleosidase from Escherichia coli". Biochim. Biophys. Acta 438 (2): 487–94. 1976. doi:10.1016/0005-2744(76)90264-3. PMID 782530.
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