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:||Biosynthesis → Nucleosides and Nucleotides Biosynthesis → Purine Nucleotide Biosynthesis → Purine Nucleotide Salvage → Adenine and Adenosine Salvage|
Adenosine nucleotides can be synthesized de novo. In that route AMP (AMP) is synthesized via IMP (IMP) and adenylo-succinate, which is converted to AMP by the action of adenylosuccinate lyase (see superpathway of adenosine nucleotides de novo biosynthesis II). Note that the free base adenine or the ribonucleoside adenosine are not produced via the de novo pathway.
Many organisms can also recycle adenosine nucleotides by a combination of degradation and salvage pathways. The degradation pathways are responsible for the conversion of the nucleotides to the nucleoside ( adenosine) and free base form ( adenine), and further degradation to compounds that can be catabolized to basic building blocks (for example, see adenosine nucleotides degradation II).
The enzyme adenosine kinase (EC 220.127.116.11) can phosphorylate adenosine directly to the mono-nucleotide AMP. The enzyme has been described in bacteria, yeast, plants and animals [Leibach71, Spychala96, Moffatt00, Wang05, Rajkarnikar07, Lu09].
Either of these routes enables the organism to salvage the degradation products of adenosine nucleotides, and recycle them back to nucleotide form.
Superpathways: superpathway of purine nucleotide salvage
Leibach71: Leibach TK, Spiess GI, Neudecker TJ, Peschke GJ, Puchwein G, Hartmann GR (1971). "Purification and properties of adenosine kinase from dried brewer's yeast." Hoppe Seylers Z Physiol Chem 352(3);328-44. PMID: 5092557
Lu09: Lu GT, Tang YQ, Li CY, Li RF, An SQ, Feng JX, He YQ, Jiang BL, Tang DJ, Tang JL (2009). "An adenosine kinase exists in Xanthomonas campestris pathovar campestris and is involved in extracellular polysaccharide production, cell motility, and virulence." J Bacteriol 191(11);3639-48. PMID: 19329636
Moffatt00: Moffatt BA, Wang L, Allen MS, Stevens YY, Qin W, Snider J, von Schwartzenberg K (2000). "Adenosine kinase of Arabidopsis. Kinetic properties and gene expression." Plant Physiol 124(4);1775-85. PMID: 11115893
Rajkarnikar07: Rajkarnikar A, Kwon HJ, Suh JW (2007). "Role of adenosine kinase in the control of Streptomyces differentiations: Loss of adenosine kinase suppresses sporulation and actinorhodin biosynthesis while inducing hyperproduction of undecylprodigiosin in Streptomyces lividans." Biochem Biophys Res Commun 363(2);322-8. PMID: 17869216
Spychala96: Spychala J, Datta NS, Takabayashi K, Datta M, Fox IH, Gribbin T, Mitchell BS (1996). "Cloning of human adenosine kinase cDNA: sequence similarity to microbial ribokinases and fructokinases." Proc Natl Acad Sci U S A 93(3);1232-7. PMID: 8577746
Wang05: Wang Y, Long MC, Ranganathan S, Escuyer V, Parker WB, Li R (2005). "Overexpression, purification and crystallographic analysis of a unique adenosine kinase from Mycobacterium tuberculosis." Acta Crystallogr Sect F Struct Biol Cryst Commun 61(Pt 6);553-7. PMID: 16511094
McNally97: McNally T, Helfrich RJ, Cowart M, Dorwin SA, Meuth JL, Idler KB, Klute KA, Simmer RL, Kowaluk EA, Halbert DN (1997). "Cloning and expression of the adenosine kinase gene from rat and human tissues." Biochem Biophys Res Commun 231(3);645-50. PMID: 9070863
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