Ornithine decarboxylase (ODC) catalyses the conversion of ornithine to putrescine, an obligate precursor to the polyamines spermidine and spermine. We reported previously that homozygous odc-1 (pc13) worms have no detectable ODC activity. Despite their inability to make polyamines, these mutant worms appear normal, but with a slight reduction in total brood size, when grown in complex medium th...

The ColE7 operon is an SOS response regulon, which encodes bacteriocin ColE7 to kill susceptible Escherichia coli and its related enterobacteria under conditions of stress. We have observed for the first time that polyamines confer limited resistance against ColE7 on E. coli cells. Thus, this study aims to investigate the role of polyamines in modulating the protective effect of the E. coli cel...

Plant biologists fall into two categories: those who believe polyamines play an important role in plant growth and development, and those who are skeptical. The latter group by far exceeds the former. Why is this? Over the years polyamines have been implicated in being involved in a wide array of processes in plants, ranging from triggering organogenesis to protecting against stress. However, t...

S-Adenosylmethionine metabolism and its relation to the synthesis and accumulation of polyamines was studied in rat liver under various nutritional conditions, in adrenalectomized or partially hepatectomized animals and after treatment with cortisol, thioacetamide or methylglyoxal bis(guanylhydrazone) {1,1'-[(methylethanediylidine)dinitrilo]diguanidine}. Starvation for 2 days only slightly affe...

We reported previously that the synthesis of specific proteins such as OppA, Cya, and RpoS (sigma(38)), which are important for cell growth and viability, is stimulated by polyamines at the level of translation. In this study we found that the synthesis of FecI and Fis was also stimulated by polyamines at the level of translation. The FecI and Fis proteins enhance the expression of mRNAs that a...

Polyamines are ubiquitous, biogenic amines that have been implicated in diverse cellular functions in most living organisms. Ever since spermine phosphate crystals were isolated over three centuries ago, scientists have kept busy in unraveling the mystery behind biological roles of spermine and other known polyamines, viz., putrescine and spermidine. Although the pathway of polyamine biosynthes...

We report that branched polyamines, including polyamidoamide dendimers, polypropyleneimine, and polyethyleneimine, are able to purge PrP(Sc), the protease-resistant isoform of the prion protein, from scrapie-infected neuroblastoma (ScN2a) cells in culture. The removal of PrP(Sc) by these compounds depends on both the concentration of branched polymer and the duration of exposure. Chronic exposu...

Plant biologists fall into two categories: those who believe polyamines play an important role in plant growth and development, and those who are skeptical. The latter group by far exceeds the former. Why is this? Over the years polyamines have been implicated in being involved in a wide array of processes in plants, ranging from triggering organogenesis to protecting against stress. However, t...

The cellular polyamines putrescine, spermidine, and spermine accelerate the aggregation and fibrillization of -synuclein, the major protein component of Lewy bodies associated with Parkinson’s disease. Circular dichroism and fluorometric thioflavin T kinetic studies showed a transition of -synuclein from unaggregated to highly aggregated states, characterized by lag and transition phases. In th...

Polyamines are small aliphatic polycations present in all living cells. Polyamines are essential for cellular viability and are involved in regulating fundamental cellular processes, most notably cellular growth and proliferation. Being such central regulators of fundamental cellular functions, the intracellular polyamine concentration is tightly regulated at the levels of synthesis, uptake, ex...