Parent Class:

EC-Numbers → 3 -- Hydrolases → 3.13 -- Acting on carbon-sulfur bonds → 3.13.2 -- Thioether and trialkylsulfonium hydrolases

Synonyms: S-adenosylhomocysteine synthase, S-adenosylhomocysteine hydrolase (ambiguous), adenosylhomocysteine hydrolase, S-adenosylhomocysteinase, SAHase, AdoHcyase

Systematic Name: S-adenosyl-L-homocysteine hydrolase

Unification Links: BRENDA:3.13.2.1, ENZYME:3.13.2.1, IUBMB-ExplorEnz:3.13.2.1

Supersedes EC number: 3.3.1.1

Reaction:
S-adenosyl-L-homocysteine + H₂O → L-homocysteine + adenosine

Enzymes and Genes:
adenosylhomocysteinase: AHCY ( Homo sapiens )
S-adenosylhomocysteine hydrolase ( Lupinus luteus )
S-adenosylhomocysteine hydrolase: Ahcy ( Rattus norvegicus )

Summary:
The enzyme contains one tightly bound NAD⁺ per subunit. This appears to bring about a transient oxidation at C-3′ of the 5′-deoxyadenosine residue, thus labilizing the thioether bond [Palmer79] (for mechanism, click here), cf. EC 5.5.1.4, inositol-3-phosphate synthase.

Citations: [De59]

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References

De59: De La Haba G, Cantoni GL (1959). "The enzymatic synthesis of S-adenosyl-L-homocysteine from adenosine and homocysteine." J Biol Chem 234(3);603-8. PMID: 13641268

Palmer79: Palmer JL, Abeles RH (1979). "The mechanism of action of S-adenosylhomocysteinase." J Biol Chem 254(4);1217-26. PMID: 762125

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Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 46(D1):D633-D639 2018
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