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Showing 1 to 20 of 46 for “"Putrescine"”.
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Systemic administration of putrescine induces GABA-like behaviors in rats
Putrescine is a polyamine with multiple roles in cellular metabolism. It is also a minor precursor of the inhibitory neurotransmitter, gamma-aminobutyric acid (GABA). Conversion of systemically administered putrescine to GABA in rat neural tissues has been reported. In this thesis, three …
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Regulation of the speC gene encoding ornithine decarboxylase in Escherichia coli by putrescine, spermidine and cAMP
… the decarboxylation of ornithine to produce putrescine. The two polyamines, putrescine and spermidine, and the cyclic AMP (CAMP) - cAMP receptor protein (CRP) are known to inhibit the expression of ODC via undefined mechanisms. A single copy of the speC’-lacZ fusion plasmid pOL-1, containing …
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Establishment of CRISPR-Cas-based gene deletions in Bacillus methanolicus and metabolic engineering towards the production of N-methylglutamate and putrescine
… polyamide produced by condensing biogenic putrescine with adipic acid to create a highly stable material. Putrescine itself is a linear four-carbon diamine involved in various cellular processes and stress responses in organisms, and it can be synthesized via two primary biochemical …
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Characterization of the interaction of putrescine and the adenosine-3' ,5'-cyclic monophosphate-cAMP receptor protein complex in the regulation of the speC gene encoding ornithine decarboxylase in Escherichia coli
… of ornithine to produce the diamine, putrescine, in the bacterium Escherichia coli. The speC gene encoding ODC has been shown to be subject to transcriptional repression by either putrescine or the cAMP- cAMP receptor protein (CRP) complex. To determine whether these regulatory modes …
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Transgenic manipulation of polyamine metabolism in poplar
… enzyme activity, several fold higher amounts of putrescine, a small increase in spermidine, and a small reduction in spermine as compared with non-transgenic (NT) cells. The conversion of labeled ornithine into putrescine was significantly higher in the transgenic than the NT cells.</p><p>The …
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Toxicology and pharmacology of N¹-acetylspermidine and N⁸-acetylspermidine
… spermidine, spermine and putrescine, were determined by intraperitoneal injection in mice. The LD<sub>50</sub> for N<sup>1</sup>-acetylspermidine •2HCl and N<sup>8</sup>-acetylspermidine •2HCl were 1150 and 820 mg/kg, respectively, and the respective LD<sub>50</sub> for …
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Characterization and regulation of the speA gene in Escherichia coli
… decarboxylase (ADC), the first enzyme in a putrescine biosynthetic pathway. ADC converts arginine to agmatine, which is hydrolyzed by agmatine ureohydrolase, encoded by the speB gene, to putrescine and urea. ADC is negatively regulated by mechanisms requiring either cAMP and cAMP receptor …
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Biogenic Amine Analysis of Fresh and Stored Bluefish (Pomatomus Saltatrix) and Microbiological Survey of Histamine-Forming Bacte
Changes in histamine, putrescine, and cadaverine concentrations in fresh and stored bluefish (Pomatomus saltatrix) were determined using a new HPLC method. The HPLC method utilized a 5.0% (w/v) trichloroacetic acid (TCA) extraction, pre-column fluorescamine derivitization, and fluorescence …
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The potential antioxidant and anticancer properties of polyamines and their response to high-intensity ultrasonication
… animals. The polyamines spermine, spermidine and putrescine have been of primary interest, as they participate in cell growth and proliferation and thus are involved in health, disease and aging. Polyamines are also reported as secondary metabolites in stress response in plants. However, many of …
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Understanding polyamine metabolism through transgenic manipulation in poplar suspension cultures
… The commonly occurring polyamines in plants are putrescine, spermidine, and spermine. Suspension cultures of poplar (Populus nigra x maximowiczii), transformed with a mouse ornithine decarboxylase gene (under the control of a 2X 35S CaMV promoter) were used to study the impact of up-regulation of …
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THE REGULATION OF POLYAMINES AND THEIR ROLE IN THE PROLIFERATION OF HELA CELLS
… of 0.5 (mu)M-spermine or spermidine or 10 (mu)M-putrescine to the HeLa cell cultures at the time of refeeding with fresh medium. Much higher concentrations (1 mM) of the non-physiological diamines, 1,3-diaminopropane or 1,3-diamino-2-hydroxy-propane, were required to eliminate the stimulation of …
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The Role of Polyamines in Osmotic Stress Tolerance in Gulf Killifish Fundulus Grandis
… gill Odc activity and in the concentrations of putrescine, spermidine, and spermine. DFMO application inhibited Odc activity and reduced polyamine levels after hypoosmotic exposure (0.1 ppt). Although gill putrescine levels remained elevated throughout the first 7 d post transfer to 0.1 ppt, the …
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Characterization of the expression profile of polyamine biosynthetic genes (Spermidine synthase) and polyamine metabolic regulation in arabidopsis
… polyamines showed a short half-life of 6-8 h for putrescine and longer ones for spermidine (>40 h) and spermine (>10 h). Catabolic rate of putrescine was proportionate to its endogenous level. Spermine was degraded mainly via back-conversion into spermidine while spermidine showed both …
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Therapeutic Potential of Prmt5 and Mat2A As Synthetic Lethal Targets In Mtap-Deficient Gbm Tumors
… inhibitors. Moreover, we have demonstrated that putrescine, a metabolite in the polyamine biosynthesis pathway, can stimulate MTA production, and enhance the efficacy of PRMT5 inhibitor treatment in <em>MTAP</em>-deleted cells across multiple tumor cell lines, even in the presence of …
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Mechanistic Studies of Flavin-Dependent Monooxygenases Involved in Bacterial Defense and Plant Metabolism
… FMOs from bacteria and plants is described. The putrescine N-monooxygenase (NMO) FbsI from Acinetobacter baumannii is involved in the fimsbactin siderophore biosynthetic pathway, a virulence factor that allows acquisition of free iron from a human host by a pathogen. We show that putrescine is …
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Characterization of the Diverse Substrate Specificities and Biological Roles of Polyamine Biosynthetic Enzymes in Microorganisms
… solved in the presence of the reaction products putrescine and cadaverine to 1.7 and 2.15 Å, respectively. The overall structure is similar to eukaryotic ODC, however reorientation of the 310-helix enlarges the substrate binding-pocket, thereby allowing L-lysine to be accommodated. The structure …
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Impact of intestinal bacteria on the anatomy and physiology of the intestinal tract in the PRM/Alf mouse model
… SIHUMI mice, which was mainly due to increased putrescine concentrations. However, no differences were observed in crypt depth, mucosa thickness and epithelial proliferation. In PRM/Alf mice, the intestine of conventional mice was 8.5 % longer compared to germfree mice. In contrast, intestinal …
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Investigations into the molecular evolution of plant terpene, alkaloid, and urushiol biosynthetic enzymes
… either nicotine/tropane alkaloid biosynthesis (putrescine N-methyltransferase) or primary metabolism (spermidine synthase) by attempting to interconvert a spermidine synthase to encode putrescine N-methyltransferase activity based upon past patterns of natural selection. In contrast to the …
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Metabolomic Approaches in Parasitology
… a critical role in cell survival by producing putrescine and spermidine, essential for various cellular processes. L-Ornithine, the precursor for putrescine biosynthesis, is believed to be obtained by uptake from the environment, as T. brucei lacks a functional arginase enzyme. I characterized …
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