Compounds like putrescine, spermidine, and spermine play important roles in both eukaryotic and prokaryotic cells and show many other different biological functions. Most eukaryotic cells have a polyamine transporter system on their cell membrane that facilitates the internalization of exogenous polyamines. This system is highly active in rapidly proliferating cells and is the target of many sophisticated chemotherapeutics currently under development.

They also have been found to act as promoters of programmed ribosomal frame shifting during translation, as modulators of a variety of ion channels and receptors and play an important role in cell growth pathways. Participation in initiating the expression of SOS response of Colicin E7 operon, down-regulation of proteins that are essential for colicin E7 uptake, enhancing the permeability of the blood–brain barrier, binding to DNA as cations are only a few of many other biological functions and targets for drug development either as carrier or as structural key element.

References:

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