Biochemistry
Putrescine attacks decarboxylated S-adenosyl methionine and gets converted to spermidine. Spermidine in turn attacks another decarboxylated S-adenosyl methionine and gets converted to spermine.
Putrescine is synthesized in small quantities by healthy living cells by the action of ornithine decarboxylase. The polyamines, of which putrescine is one of the simplest, appear to be growth factors necessary for cell division.
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