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Description |
The polyamines Spermidine and Spermine are naturally occurring ubiquitous polycations involved in the regulation of cell growth, differentiation, apoptosis and progression through the cell cycle. (Ref.1). Cellular polyamine levels are regulated by multiple pathways such as synthesis from amino acid precursors, cellular uptake mechanisms that salvage polyamines from diet and intestinal microorganisms, as well as stepwise degradation and efflux (Ref.2).
Putrescine and S-Adenosylmethionine are the obligate precursors for Spermidine and Spermine. In mammals Putrescine is formed by decarboxylation of Ornithine by the action of Ornithine Decarboxylase. Ornithine, one of the starting materials for polyamine biosynthesis, is derived from the amino acid Arginine as part of the urea cycle. Before reacting with Putrescine to form Spermidine, S-Adenosylmethionine is first decarboxylated to [...] |
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