Biology:Adenosylhomocysteine nucleosidase

From HandWiki
adenosylhomocysteine nucleosidase
Identifiers
EC number3.2.2.9
CAS number9055-10-1
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO

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.