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MetaCyc Pathway: S-methyl-5'-thioadenosine degradation I
Inferred from experiment

Enzyme View:

Pathway diagram: S-methyl-5'-thioadenosine degradation I

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.

Superclasses: Degradation/Utilization/AssimilationNucleosides and Nucleotides DegradationS-methyl-5'-thioadenosine Degradation

Some taxa known to possess this pathway include : Arabidopsis thaliana col, Bacillus subtilis, Klebsiella oxytoca, Klebsiella pneumoniae, Lupinus luteus, Oryza sativa

Expected Taxonomic Range: Archaea, Bacteria , Embryophyta

General Background

S-methyl-5'-thioadenosine (MTA) is a side product in the biosynthesis of several important compounds. An important case is polyamine synthesis, where L-methionine is consumed through the utilization of S-adenosyl-L-methionine (SAM) in a reaction that releases MTA (see the pathway superpathway of polyamine biosynthesis II). MTA is a strong inhibitor of polyamine biosynthesis and transmethylation reactions, and its concentration needs to be tightly regulated.

Another example is found in the pathogen Pseudomonas aeruginosa, where MTA is a by product in the synthesis of the autoinducer compounds PAI-1 and PAI-1-2 (see autoinducer AI-1 biosynthesis).

To ensure that the pathways that produce MTA as a byproduct are not blocked, the organism must remove this compound. The most common way of achieving it is through the methionine salvage pathway, in which MTA is recycled through a series of reactions back to AMP and L-methionine. While the methionine salvage pathway is widely conserved, its initial steps, converting MTA to S-methyl-5-thio-α-D-ribose 1-phosphate, differ among microorganisms and plants (such as the bacteria Klebsiella pneumoniae [Cornell96] and Bacillus subtilis [Sekowska02]), protozoans (such as Giardia intestinalis and Plasmodium falciparum [Riscoe88]) and mammalian cells. The different routes employed by these organisms are described in the different pathways under S-methyl-5'-thioadenosine Degradation.

About This Pathway

This pathway is found mostly in bacteria and plants. In it MTA is degraded to S-methyl-5-thio-α-D-ribose 1-phosphate (MTRP) in two steps; MTA is initially cleaved to adenine and S-methyl-5-thio-D-ribose (MTR) by 5'-methylthioadenosine nucleosidase, followed by phosphorylation of MTR to MTRP by 5'-methylthioribose kinase.

Superpathways: L-methionine salvage cycle II (plants), L-methionine salvage cycle I (bacteria and plants)

Variants: S-methyl-5'-thioadenosine degradation II, S-methyl-5'-thioadenosine degradation III, S-methyl-5'-thioadenosine degradation IV

Created 16-Mar-2011 by Caspi R, SRI International


Cornell96: Cornell KA, Winter RW, Tower PA, Riscoe MK (1996). "Affinity purification of 5-methylthioribose kinase and 5-methylthioadenosine/S-adenosylhomocysteine nucleosidase from Klebsiella pneumoniae." Biochem J 1996;317 ( Pt 1);285-90. PMID: 8694776

Miyazaki87a: Miyazaki J.H., Yang S.F. "The methionine salvage pathway in relation to ethylene and polyamine biosynthesis." Physiol. Plantarum (1987) 69 : 366-370.

Riscoe88: Riscoe MK, Ferro AJ, Fitchen JH (1988). "Analogs of 5-methylthioribose, a novel class of antiprotozoal agents." Antimicrob Agents Chemother 1988;32(12);1904-6. PMID: 2854458

Sekowska02: Sekowska A, Danchin A (2002). "The methionine salvage pathway in Bacillus subtilis." BMC Microbiol 2002;2(1);8. PMID: 12022921

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

Allart98: Allart B, Gatel M, Guillerm D, Guillerm G (1998). "The catalytic mechanism of adenosylhomocysteine/methylthioadenosine nucleosidase from Escherichia coli--chemical evidence for a transition state with a substantial oxocarbenium character." Eur J Biochem 256(1);155-62. PMID: 9746359

Cornell96a: Cornell KA, Swarts WE, Barry RD, Riscoe MK (1996). "Characterization of recombinant Eschericha coli 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase: analysis of enzymatic activity and substrate specificity." Biochem Biophys Res Commun 228(3);724-32. PMID: 8941345

Cornell98: Cornell KA, Riscoe MK (1998). "Cloning and expression of Escherichia coli 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase: identification of the pfs gene product." Biochim Biophys Acta 1396(1);8-14. PMID: 9524204

Della85: Della Ragione F, Porcelli M, Carteni-Farina M, Zappia V, Pegg AE (1985). "Escherichia coli S-adenosylhomocysteine/5'-methylthioadenosine nucleosidase. Purification, substrate specificity and mechanism of action." Biochem J 232(2);335-41. PMID: 3911944

Gianotti90: Gianotti AJ, Tower PA, Sheley JH, Conte PA, Spiro C, Ferro AJ, Fitchen JH, Riscoe MK (1990). "Selective killing of Klebsiella pneumoniae by 5-trifluoromethylthioribose. Chemotherapeutic exploitation of the enzyme 5-methylthioribose kinase." J Biol Chem 1990;265(2);831-7. PMID: 2153115

Guranowski81: Guranowski AB, Chiang PK, Cantoni GL (1981). "5'-Methylthioadenosine nucleosidase. Purification and characterization of the enzyme from Lupinus luteus seeds." Eur J Biochem 114(2);293-9. PMID: 6783408

Guranowski83: Guranowski A. "Plant 5-methylthioribose kinase." Plant Physiol. (1983) 71 : 932-935.

Guranowski83a: Guranowski A.B., Chiang P.K., Cantoni G.L. "5'-Methylthioadenosine nucleosidase (Lupinus luteus seeds)." Methods in enzymology (1983) 94 : 365-369.

Gutierrez09: Gutierrez JA, Crowder T, Rinaldo-Matthis A, Ho MC, Almo SC, Schramm VL (2009). "Transition state analogs of 5'-methylthioadenosine nucleosidase disrupt quorum sensing." Nat Chem Biol 5(4):251-7. PMID: 19270684

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

Lee05c: Lee JE, Luong W, Huang DJ, Cornell KA, Riscoe MK, Howell PL (2005). "Mutational analysis of a nucleosidase involved in quorum-sensing autoinducer-2 biosynthesis." Biochemistry 44(33);11049-57. PMID: 16101288

Li11c: Li X, Apel D, Gaynor EC, Tanner ME (2011). "5'-methylthioadenosine nucleosidase is implicated in playing a key role in a modified futalosine pathway for menaquinone biosynthesis in Campylobacter jejuni." J Biol Chem 286(22);19392-8. PMID: 21489995

Sauter04: Sauter M, Cornell KA, Beszteri S, Rzewuski G (2004). "Functional analysis of methylthioribose kinase genes in plants." Plant Physiol 136(4);4061-71. PMID: 15557090

Sekowska99: Sekowska A, Danchin A (1999). "Identification of yrrU as the methylthioadenosine nucleosidase gene in Bacillus subtilis." DNA Res 6(5);255-64. PMID: 10574451

Tower91: Tower PA, Johnson LL, Ferro AJ, Fitchen JH, Riscoe MK (1991). "Synergistic activity of 5-trifluoromethylthioribose and inhibitors of methionine synthesis against Klebsiella pneumoniae." Antimicrob Agents Chemother 1991;35(8);1557-61. PMID: 1929327

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by Pathway Tools version 19.5 (software by SRI International) on Mon May 2, 2016, biocyc14.