Reaction: (1) S-adenosyl-L-homocysteine + H2O = S-(5-deoxy-D-ribos-5-yl)-L-homocysteine + adenine
(2) 5'-deoxyadenosine + H2O = 5-deoxy-D-ribose + adenine
(3) S-methyl-5'-thioadenosine + H2O = 5-(methylsulfanyl)-D-ribose + adenine
For diagram of autoinducer AI-2 biosynthesis, click here and for diagram of the methionine-salvage pathway, click here
Other name(s): S-adenosylhomocysteine hydrolase (ambiguous); S-adenosylhomocysteine nucleosidase; 5'-methyladenosine nucleosidase; S-adenosylhomocysteine/5'-methylthioadenosine nucleosidase; AdoHcy/MTA nucleosidase; MTN2 (gene name); mtnN (gene name)
Systematic name: S-adenosyl-L-homocysteine homocysteinylribohydrolase
Comments: This enzyme, found in bacteria and plants, acts on three different substrates. It is involved in the S-adenosyl-L-methionine (SAM, AdoMet) cycle, which recycles S-adenosyl-L-homocysteine back to SAM, and in salvage pathways for 5'-deoxyadenosine and S-methyl-5'-thioadenosine, which are produced from SAM during the action of many enzymes. cf. the plant enzyme EC 126.96.36.199, methylthioadenosine nucleosidase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9055-10-1
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