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MetaCyc Pathway: S-adenosyl-L-methionine biosynthesis
Traceable author statement to experimental supportInferred from experiment

Enzyme View:

Pathway diagram: S-adenosyl-L-methionine biosynthesis

This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.

Synonyms: S-adenosylmethionine biosynthesis

Superclasses: BiosynthesisCofactors, Prosthetic Groups, Electron Carriers Biosynthesis

Some taxa known to possess this pathway include : Arabidopsis thaliana colInferred from experiment [Peleman89], Escherichia coli K-12 substr. MG1655Inferred from experiment, Saccharomyces cerevisiae

Expected Taxonomic Range: Archaea, Bacteria , Fungi, Viridiplantae

It has been said that no biological compound functions in as many different types of biological reactions as S-adenosyl-L-methionine (known as SAM or AdoMet). It is probably second only to ATP in the variety of reactions for which it serves as a cofactor. SAM is found in all living organisms, and fulfils three important roles:

* In transmethylation, SAM is the principal biological methyl donor.

* In transsulfuration, the sulfur atom of the SAM is converted via a series of enzymatic steps to cysteine, a precursor of taurine and glutathione, a major cellular anti-oxidant.

* In polyamine biosynthesis, SAM is the donor of aminopropyl groups.

The structure of SAM was first elucidated by Cantoni in 1951 [Cantoni51]. The key to SAM's activity lies in the presence of the high energy sulfonium ion, which activates each of the attached carbons toward nucleophilic attack. In most cases, SAM reacts by transfer of the S-methyl group to a long list of possible acceptors in transmethylation reactions.

SAM is synthesized in the cytosol of every cell from L-methionine and ATP, in a reaction catalyzed by methionine adenosyltransferase. In animals, up to half of the daily intake of L-methionine is converted to SAM. In this unusual reaction, the adenosyl moiety of ATP is transferred to methionine, forming a sulfonium ion which is a high energy reagent that can easily transfer its methyl group to a large variety of acceptor substrates including nucleic acids, proteins, phospholipids, biologic amines, and a long list of small molecules [Lu00].

Superpathways: superpathway of S-adenosyl-L-methionine biosynthesis, L-methionine salvage cycle III, L-methionine salvage cycle II (plants), L-methionine salvage cycle I (bacteria and plants), S-adenosyl-L-methionine cycle I, aspartate superpathway

Unification Links: EcoCyc:SAM-PWY

Created 08-Jul-1994 by Riley M, Marine Biological Laboratory


Cantoni51: Cantoni, G. L. (1951). "Methylation of nicotinamide with a soluble enzyme system from rat liver." J. Biol. Chem. 189: 203 - 216.

Lu00: Lu, S. C. (2000). "S-Adenosylmethionine." The International Journal of Biochemistry & Cell Biology 32(4): 391-395.

Peleman89: Peleman J, Boerjan W, Engler G, Seurinck J, Botterman J, Alliotte T, Van Montagu M, Inze D (1989). "Strong cellular preference in the expression of a housekeeping gene of Arabidopsis thaliana encoding S-adenosylmethionine synthetase." Plant Cell 1989;1(1);81-93. PMID: 2535470

Other References Related to Enzymes, Genes, Subpathways, and Substrates of this Pathway

Arifuzzaman06: Arifuzzaman M, Maeda M, Itoh A, Nishikata K, Takita C, Saito R, Ara T, Nakahigashi K, Huang HC, Hirai A, Tsuzuki K, Nakamura S, Altaf-Ul-Amin M, Oshima T, Baba T, Yamamoto N, Kawamura T, Ioka-Nakamichi T, Kitagawa M, Tomita M, Kanaya S, Wada C, Mori H (2006). "Large-scale identification of protein-protein interaction of Escherichia coli K-12." Genome Res 16(5);686-91. PMID: 16606699

Bairoch93a: Bairoch A, Boeckmann B (1993). "The SWISS-PROT protein sequence data bank, recent developments." Nucleic Acids Res. 21:3093-3096. PMID: 8332529

BRENDA14: BRENDA team (2014). Imported from BRENDA version existing on Aug 2014.

Cabrero87: Cabrero C, Puerta J, Alemany S (1987). "Purification and comparison of two forms of S-adenosyl-L-methionine synthetase from rat liver." Eur J Biochem 170(1-2);299-304. PMID: 3121322

Chattopadhyay91: Chattopadhyay MK, Ghosh AK, Sengupta S (1991). "Control of methionine biosynthesis in Escherichia coli K12: a closer study with analogue-resistant mutants." J Gen Microbiol 137(3);685-91. PMID: 2033383

Chiang77: Chiang PK, Cantoni GL (1977). "Activation of methionine for transmethylation. Purification of the S-adenosylmethionine synthetase of bakers' yeast and its separation into two forms." J Biol Chem 1977;252(13);4506-13. PMID: 194884

Chou72: Chou TC, Talalay P (1972). "The mechanism of S-adenosyl-L-methionine synthesis by purified preparations of bakers' yeast." Biochemistry 1972;11(6);1065-73. PMID: 4552214

DiazMejia09: Diaz-Mejia JJ, Babu M, Emili A (2009). "Computational and experimental approaches to chart the Escherichia coli cell-envelope-associated proteome and interactome." FEMS Microbiol Rev 33(1);66-97. PMID: 19054114

Fu96: Fu Z, Hu Y, Markham GD, Takusagawa F (1996). "Flexible loop in the structure of S-adenosylmethionine synthetase crystallized in the tetragonal modification." J Biomol Struct Dyn 13(5);727-39. PMID: 8723769

GOA01: GOA, MGI (2001). "Gene Ontology annotation based on Enzyme Commission mapping." Genomics 74;121-128.

GOA01a: GOA, DDB, FB, MGI, ZFIN (2001). "Gene Ontology annotation through association of InterPro records with GO terms."

GOA06: GOA, SIB (2006). "Electronic Gene Ontology annotations created by transferring manual GO annotations between orthologous microbial proteins."

Greene73: Greene RC, Hunter JS, Coch EH (1973). "Properties of metK mutants of Escherichia coli K-12." J Bacteriol 115(1);57-67. PMID: 4577753

Ishihama08: Ishihama Y, Schmidt T, Rappsilber J, Mann M, Hartl FU, Kerner MJ, Frishman D (2008). "Protein abundance profiling of the Escherichia coli cytosol." BMC Genomics 9;102. PMID: 18304323

Kamarthapu08: Kamarthapu V, Rao KV, Srinivas PN, Reddy GB, Reddy VD (2008). "Structural and kinetic properties of Bacillus subtilis S-adenosylmethionine synthetase expressed in Escherichia coli." Biochim Biophys Acta 1784(12);1949-58. PMID: 18634909

Komoto04: Komoto J, Yamada T, Takata Y, Markham GD, Takusagawa F (2004). "Crystal structure of the S-adenosylmethionine synthetase ternary complex: a novel catalytic mechanism of S-adenosylmethionine synthesis from ATP and Met." Biochemistry 43(7);1821-31. PMID: 14967023

Lasserre06: Lasserre JP, Beyne E, Pyndiah S, Lapaillerie D, Claverol S, Bonneu M (2006). "A complexomic study of Escherichia coli using two-dimensional blue native/SDS polyacrylamide gel electrophoresis." Electrophoresis 27(16);3306-21. PMID: 16858726

Latendresse13: Latendresse M. (2013). "Computing Gibbs Free Energy of Compounds and Reactions in MetaCyc."

Lee97b: Lee JH, Chae HS, Lee JH, Hwang B, Hahn KW, Kang BG, Kim WT (1997). "Structure and expression of two cDNAs encoding S-adenosyl-L-methionine synthetase of rice (Oryza sativa L.)." Biochim Biophys Acta 1354(1);13-8. PMID: 9375784

LopezCampistrou05: Lopez-Campistrous A, Semchuk P, Burke L, Palmer-Stone T, Brokx SJ, Broderick G, Bottorff D, Bolch S, Weiner JH, Ellison MJ (2005). "Localization, annotation, and comparison of the Escherichia coli K-12 proteome under two states of growth." Mol Cell Proteomics 4(8);1205-9. PMID: 15911532

Showing only 20 references. To show more, press the button "Show all references".

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Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
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