4509 T3D4455 S-Adenosylhomocysteine S-Adenosylhomocysteine (AdoHcy) is the immediate precursor of all of the homocysteine produced in the body. The reaction is catalyzed by S-adenosylhomocysteine hydrolase and is reversible with the equilibrium favoring formation of AdoHcy. In vivo, the reaction is driven in the direction of homocysteine formation by the action of the enzyme adenosine deaminase, which converts the second product of the S-adenosylhomocysteine hydrolase reaction, adenosine, to inosine. Except for methyl transfer from betaine and from methylcobalamin in the methionine synthase reaction, AdoHcy is the product of all methylation reactions that involve S-adenosylmethionine (AdoMet) as the methyl donor. Methylation is significant in epigenetic regulation of protein expression via DNA and histone methylation. The inhibition of these AdoMet-mediated processes by AdoHcy is a proven mechanism for metabolic alteration. Because the conversion of AdoHcy to homocysteine is reversible, with the equilibrium favoring the formation of AdoHcy, increases in plasma homocysteine are accompanied by an elevation of AdoHcy in most cases. Disturbances in the transmethylation pathway indicated by abnormal S-adenosylmethionine, S-adenosylhomocysteine or their ratio have been reported in many neurodegenerative diseases, such as dementia, depression or Parkinson's disease. (A3511, A3512). 979-92-0 439155 C14H20N6O5S White powder. 209 - 211°C No indication of carcinogenicity to humans (not listed by IARC). This is an endogenously produced metabolite found in the human body. It is used in metabolic reactions, catabolic reactions or waste generation. Chronically high levels of S-adenosylhomocysteine are associated with S-Adenosylhomocysteine (SAH) Hydrolase Deficiency. 2014-08-29T06:51:24Z 2026-05-14T17:15:07Z SAH C00021 16680 ADENOSYL-HOMO-CYS DB01752 SAH true N[C@@H](CCSC[C@H]1O[C@H]([C@H](O)[C@@H]1O)N1C=NC2=C(N)N=CN=C12)C(O)=O C14H20N6O5S InChI=1S/C14H20N6O5S/c15-6(14(23)24)1-2-26-3-7-9(21)10(22)13(25-7)20-5-19-8-11(16)17-4-18-12(8)20/h4-7,9-10,13,21-22H,1-3,15H2,(H,23,24)(H2,16,17,18)/t6-,7+,9+,10+,13+/m0/s1 ZJUKTBDSGOFHSH-WFMPWKQPSA-N 384.411 384.12158847 Endogenous Solid -4 HMDB00939 CHEMBL418052 388301 <p>Hideaki Yamada, Sakayu Shimizu, Shozo Shiozaki, &#8220;Process for producing S-adenosyl-L-homocysteine.&#8221; U.S. Patent US4605625, issued March, 1978.</p> CHEM003415 DTXSID30895860 NS00014918 (2S)-2-amino-4-({[(2S,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxyoxolan-2-yl]methyl}sulfanyl)butanoic acid 182.63000000000005 92.7235 38.405820699013795 7 10 5 1.8086867060766885 9.501849806722712 0 3 -2.37 -1.97 4.08e+00 g/l