Ray, Ramesh M., Mary Jane Viar, Qing Yuan, and L. R. Johnson. Polyamine depletion delays apoptosis of rat intestinal epithelial cells. Am. J. Physiol. Cell Physiol. 278: C480–C489, 2000.—The polyamines spermidine, spermine, and their precursor putrescine are essential for cell growth and the regulation of the cell cycle. Recent studies suggest that excessive accumulation of polyamines favors ei...

Confluent Ob1771 cells treated with an inhibitor of spermidine and spermine synthesis, methylglyoxyal bis(guanylhydrazone), were dependent on putrescine addition for the expression of glycerol-3-phosphate dehydrogenase and acyl-CoA synthetase, which behaved as late markers of adipose conversion. A similar dependence was observed with drug-treated Ob17MT18 and 3T3-F442A preadipocyte cells, but n...

Plum fruit has a short shelf life with a rapid deterioration in quality after harvest. The primary goal of this study is to investigate and compare the effect of putrescine and salicylic acid on quality properties and antioxidant activity of plum during storage. The plum fruits (cv. 'Santa Rosa') were harvested at the mature ripe stage, and dipped in different concentrations of putrescine (1, 2...

seedless grapes are widely grown all over the world. embryo rescue technique proved to be able to overcome the problem of embryo abortion in seedless grape breeding program. since, the efficiency of this technique is not desirable, so a lot of efforts have been done in different directions in order to improve this technique. this study was conducted in two separate experiments in which chlormeq...

today, hormones and nutrients are used in order to improve vegetative and reproductive growth of many agricultural products in the world. the purpose of this study, was to increase fruit set, fruit weight, and finally, increase of yield along with improvement of vegetative growth with putrescine treatments (0, 0.01, 0.001m) and potassium nitrate (0, 2 and 4%) of quince (cydonia oblonga cv. esfa...

This method for assay of polyamines (putrescine, spermidine, and spermine) in large numbers of urine samples is based on preliminary analyte isolation by use of a Dowex 50W column, separation by high-voltage paper electrophoresis, reaction with ninhydrin to detect the separated amines, and subsequent direct assay with a dual-wave-length thin-layer chromatography scanner by the zigzag scanning m...

The TcPOT1.1 gene from Trypanosoma cruzi encodes a high affinity putrescine-cadaverine transporter belonging to the APC (amino acid/polyamine/organocation) transporter superfamily. No experimental three-dimensional structure exists for any eukaryotic member of the APC family, and thus the structural determinants critical for function of these permeases are unknown. To elucidate the key residues...

A pot experiment was conducted in the screen of the National Research Centre during two successive seasons to study the response of periwinkle plants to foliar spray with tryptophan or putrescine at the concentrations 10 M, 10 M or 10 M. The obtained data indicated that exogenous application of tryptophan or putrescine on periwinkle transplants considerably increased plant growth at successive ...

DH23A cells, an alpha-difluoromethylornithine-resistant variant of the parental hepatoma tissue culture cells, express high levels of stable ornithine decarboxylase. Aberrantly high expression of ornithine decarboxylase results in a large accumulation of endogenous putrescine and increased apoptosis in DH23A cells when alpha-difluoromethylornithine is removed from the culture. Treatment of DH23...

YgjG is a putrescine aminotransferase enzyme that transfers amino groups from compounds with terminal primary amines to compounds with an aldehyde group using pyridoxal-5'-phosphate (PLP) as a cofactor. Previous biochemical data show that the enzyme prefers primary diamines, such as putrescine, over ornithine as a substrate. To better understand the enzyme's substrate specificity, crystal struc...