Vujcic, Slavoljub; Liang, Ping; Diegelman, Paula; Kramer, Debora L; Porter, Carl W
2003-01-01
In the polyamine back-conversion pathway, spermine and spermidine are first acetylated by spermidine/spermine N1 -acetyltransferase (SSAT) and then oxidized by polyamine oxidase (PAO) to produce spermidine and putrescine respectively. Although PAO was first purified more than two decades ago, the protein has not yet been linked to genomic sequences. In the present study, we apply a BLAST search strategy to identify novel oxidase sequences located on human chromosome 10 and mouse chromosome 7. Homologous mammalian cDNAs derived from human brain and mouse mammary tumour were deduced to encode proteins of approx. 55 kDa having 82% sequence identity. When either cDNA was transiently transfected into HEK-293 cells, intracellular spermine pools decreased by approx. 30%, whereas spermidine increased 2-4-fold. Lysates of human PAO cDNA-transfected HEK-293 cells, but not vector-transfected cells, rapidly oxidized N1-acetylspermine to spermidine. Substrate specificity determinations with the lysate assay revealed a preference ranking of N1-acetylspermine= N1-acetylspermidine> N1,N12-diacetylspermine>>spermine; spermidine was not acted upon. This ranking is identical to that reported for purified PAO and distinctly different from the recently identified spermine oxidase (SMO), which prefers spermine over N1-acetylspermine. Monoethyl- and diethylspermine analogues also served as substrates for PAO, and were internally cleaved adjacent to a secondary amine. We deduce that the present oxidase sequences are those of the FAD-dependent PAO involved in the polyamine back-conversion pathway. In Northern blot analysis, PAO mRNA was much less abundant in HEK-293 cells than SMO or SSAT mRNA, and all three were differentially induced in a similar manner by selected polyamine analogues. The identification of PAO sequences, together with the recently identified SMO sequences, provides new opportunities for understanding the dynamics of polyamine homoeostasis and for interpreting metabolic and cellular responses to clinically-relevant polyamine analogues and inhibitors. PMID:12477380
Vujcic, Slavoljub; Diegelman, Paula; Bacchi, Cyrus J; Kramer, Debora L; Porter, Carl W
2002-01-01
During polyamine catabolism, spermine and spermidine are first acetylated by spermidine/spermine N(1)-acetyltransferase (SSAT) and subsequently oxidized by polyamine oxidase (PAO) to produce spermidine and putrescine, respectively. In attempting to clone the PAO involved in this back-conversion pathway, we encountered an oxidase that preferentially cleaves spermine in the absence of prior acetylation by SSAT. A BLAST search using maize PAO sequences identified homologous mammalian cDNAs derived from human hepatoma and mouse mammary carcinoma: the encoded proteins differed by 20 amino acids. When either cDNA was transiently transfected into HEK-293 cells, intracellular spermine pools decreased by 75% while spermidine and N (1)-acetylspermidine pools increased, suggesting that spermine was selectively and directly oxidized by the enzyme. Substrate specificity using lysates of oxidase-transfected HEK-293 cells revealed that the newly identified oxidase strongly favoured spermine over N (1)-acetylspermine and that it failed to act on N (1)-acetylspermidine, spermidine or the preferred PAO substrate, N (1), N (12)-diacetylspermine. The PAO inhibitor, MDL-72,527, only partially blocked oxidation of spermine while a previously reported PAO substrate, N (1)-( n -octanesulphonyl)spermine, potently inhibited the reaction. Overall, the data indicate that the enzyme represents a novel mammalian oxidase which, on the basis of substrate specificity, we have designated spermine oxidase in order to distinguish it from the PAO involved in polyamine back-conversion. The identification of an enzyme capable of directly oxidizing spermine to spermidine has important implications for understanding polyamine homoeostasis and for interpreting metabolic and cellular responses to clinically relevant polyamine analogues and inhibitors. PMID:12141946
Satriano, J
2004-07-01
An early response to an acute inflammatory insult, such as wound healing or experimental glomerulonephritis, is the conversion of arginine to the cytostatic molecule nitric oxide (NO). This 'anti-bacterial' phase is followed by the conversion of arginine to ornithine, which is the precursor for the pro-proliferative polyamines as well as proline for the production of extracellular matrix. This latter, pro-growth phase constitutes a 'repair' phase response. The temporal switch of arginine as a substrate for the cytostatic iNOS/NO axis to the pro-growth arginase/ ornithine/polyamine and proline axis is subject to regulation by inflammatory cytokines as well as interregulation by the arginine metabolites themselves. Arginine is also the precursor for another biogenic amine, agmatine. Here we describe the capacity of these three arginine pathways to interregulate, and propose a model whereby agmatine has the potential to serve in the coordination of the early and repair phase pathways of arginine in the inflammatory response by acting as a gating mechanism at the transition from the iNOS/NO axis to the arginase/ODC/polyamine axis. Due to the pathophysiologic and therapeutic potential, we will further examine the antiproliferative effects of agmatine on the polyamine pathway.
Polyamines and cancer: Implications for chemoprevention and chemotherapy
Nowotarski, Shannon L.; Woster, Patrick M.; Casero, Robert A.
2013-01-01
Polyamines are small organic cations that are essential for normal cell growth and development in eukaryotes. Under normal physiological conditions, intracellular polyamine concentrations are tightly regulated through a dynamic network of biosynthetic and catabolic enzymes and a poorly characterized transport system. This precise regulation ensures that the intracellular concentration of polyamines is maintained within strictly controlled limits. It has frequently been observed that the metabolism of, and the requirement for, polyamines in tumours is frequently dysregulated. Elevated levels of polyamines have been associated with breast, colon, lung, prostate, and skin cancers, and altered levels of the rate limiting enzymes in both biosynthesis and catabolism have been observed. Based on these observations and the absolute requirement for polyamines in tumour growth, the polyamine pathway is a rational target for chemoprevention and chemotherapeutics. Here we describe the recent advances made in the polyamine field and focus on the roles of polyamines and polyamine metabolism in neoplasia through a discussion of the current animal models for the polyamine pathway, chemotherapeutic strategies that target the polyamine pathway, chemotherapeutic clinical trials for polyamine pathway specific drugs, and ongoing clinical trials targeting polyamine biosynthesis. PMID:23432971
Role of Polyamines in Parasite Cell Architecture and Function.
Vannier-Santos, Marcos A; Suarez-Fontes, Ana M
2017-01-01
In the absence of accessible, effective vaccines, the fight against parasitic disease relies mostly on chemotherapy. Nevertheless, the considerable side effects, high costs and growing number of refractory cases comprise substantial drawbacks. Thus, the search for new antiparasitic compounds remains a high priority. The polyamine biosynthesis, conversion and transport pathways offer different targets for selective chemotherapy. Polyamine analogues and other antagonists may provide tools in the search for new lead compounds. Light and electron microscopy techniques may encompass valuable approaches to elucidate the possible mechanisms of action of different antiparasitic compounds, allowing the identification of subcellular target compartments, presumably establishing the basis for a more rational drug design and/or planning of therapeutic strategies. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Real-Time In Vivo Monitoring of Reactive Oxygen Species in Guard Cells.
Park, Ky Young; Roubelakis-Angelakis, Kalliopi A
2018-01-01
The intra-/intercellular homeostasis of reactive oxygen species (ROS), and especially of superoxides (O 2 .- ) and hydrogen peroxide (O 2 .- ) participate in signalling cascades which dictate developmental processes and reactions to biotic/abiotic stresses. Polyamine oxidases terminally oxidize/back convert polyamines generating H 2 O 2 . Recently, an NADPH-oxidase/Polyamine oxidase feedback loop was identified to control oxidative burst under salinity. Thus, the real-time localization/monitoring of ROS in specific cells, such as the guard cells, can be of great interest. Here we present a detailed description of the real-time in vivo monitoring of ROS in the guard cells using H 2 O 2 - and O 2 .- specific fluorescing probes, which can be used for studying ROS accumulation generated from any source, including the amine oxidases-dependent pathway, during development and stress.
Wang, Wei; Liu, Ji-Hong
2015-01-25
Polyamine oxidases (PAOs) are FAD-dependent enzymes associated with polyamine catabolism. In plants, increasing evidences support that PAO genes play essential roles in abiotic and biotic stresses response. In this study, six putative PAO genes (CsPAO1-CsPAO6) were unraveled in sweet orange (Citrus sinensis) using the released citrus genome sequences. A total of 203 putative cis-regulatory elements involved in hormone and stress response were predicted in 1.5-kb promoter regions at the upstream of CsPAOs. The CsPAOs can be divided into four major groups, with similar organizations with their counterparts of Arabidopsis thaliana. Transcripts of CsPAOs were detected in leaf, stem, cotyledon, and root, with the highest levels detected in the roots. The CsPAOs displayed various responses to exogenous treatments with polyamines and ABA and were differentially altered by abiotic stresses, including cold, salt, and mannitol. Overexpression of CsPAO3 in tobacco demonstrated that spermidine and spermine were decreased in the transgenic line, while putrescine was significantly enhanced, implying a potential role of this gene in polyamine back conversion. These data provide valuable knowledge for understanding the roles of the PAO genes in the future. Copyright © 2014 Elsevier B.V. All rights reserved.
Lim, Yong-beom; Mays, Charles E; Kim, Younghwan; Titlow, William B; Ryou, Chongsuk
2010-03-01
Branched polyamines are effective in inhibiting prions in a cationic surface charge density dependent manner. However, toxicity associated with branched polyamines, in general, often hampers the successful application of the compounds to treat prion diseases. Here, we report that constitutively maintained cationic properties in branched polyamines reduced the intrinsic toxicity of the compounds while retaining the anti-prion activities. In prion-infected neuroblastoma cells, quaternization of amines in polyethyleneimine (PEI) and polyamidoamine (PAMAM) dendrimers markedly increased the nontoxic concentration ranges of the compounds and still supported, albeit reduced, an appreciable level of anti-prion activity in clearing prions from the infected cells. Furthermore, quaternized PEI was able to degrade prions at acidic pH conditions and inhibit the in vitro prion propagation facilitated by conversion of the normal prion protein isoform to its misfolded counterpart, although such activities were decreased by quaternization. Quaternized PAMAM was least effective in degrading prions but efficiently inhibited prion conversion with the same efficacy as unmodified PAMAM. Our results suggest that quaternization represents an effective strategy for developing nontoxic branched polyamines with potent anti-prion activity. This study highlights the importance of polyamine structural control for developing polyamine-based anti-prion agents and understanding of an action mechanism of quaternized branched polyamines. Copyright (c) 2009 Elsevier Ltd. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Arginine, a precursor for the synthesis of nitric oxide (NO) and polyamines, is critical for implantation and development of the conceptus. We first reported that the arginine decarboxylase (ADC)/agmatinase(AGMAT) pathway as an alternative pathway for synthesis of polyamines in the ovine conceptuses...
NASA Technical Reports Server (NTRS)
Weinstein, L. H.; Osmeloski, J. F.; Wettlaufer, S. H.; Galston, A. W.
1987-01-01
In higher plants, polyamines arise from arginine by one of two pathways: via ornithine and ornithine decarboxylase or via agmatine and arginine decarboxylase but in fungi, only the ornithine decarboxylase pathway is present. Since polyamines are required for normal growth of microorganisms and plants and since the ornithine pathway can be irreversibly blocked by alpha-difluoromethylornithine (DFMO) which has no effect on arginine decarboxylase, fungal infection of green plants might be controlled by the site-directed use of such a specific metabolic inhibitor. DFMO at relatively low concentrations provided effective control of the three biotrophic fungal pathogens studied, Puccinia recondita (leaf rust), P. graminis f. sp. tritici (stem rust), and Erysiphe graminis (powdery mildew) on wheat (Triticum aestivum L.) Effective control of infection by leaf or stem rust fungi was obtained with sprays of DFMO that ranged from about 0.01 to 0.20 mM in experiments where the inhibitor was applied after spore inoculation. The powdery mildew fungus was somewhat more tolerant of DFMO, but good control of the pathogen was obtained at less than 1.0 mM. In general, application of DFMO after spore inoculation was more effective than application before inoculation. Less control was obtained following treatment with alpha-difluoromethylarginine (DFMA) but the relatively high degree of control obtained raises the possibility of a DFMA to DFMO conversion by arginase.
Molecular Pathways: Disrupting polyamine homeostasis as a therapeutic strategy for neuroblastoma
Evageliou, Nicholas F.; Hogarty, Michael D.
2009-01-01
MYC genes are deregulated in a plurality of human cancers. Through direct and indirect mechanisms the MYC network regulates the expression of >15% of the human genome, including both protein-coding and non-coding RNAs. This complexity has complicated efforts to define the principal pathways mediating MYC’s oncogenic activity. MYC plays a central role providing for the bioenergetic and biomass needs of proliferating cells, and polyamines are essential cell constituents supporting many of these functions. The rate-limiting enzyme in polyamine biosynthesis, ODC, is a bona fide MYC target, as are other regulatory enzymes in this pathway. A wealth of data link enhanced polyamine biosynthesis to cancer progression, and polyamine-depletion may limit malignant transformation of pre-neoplastic lesions. Studies using transgenic cancer models also supports that the effect of MYC on tumor initiation and progression can be attenuated through repression of polyamine production. High-risk neuroblastomas (an often lethal embryonal tumor in which MYC activation is paramount) deregulate numerous polyamine enzymes to promote expansion of intracellular polyamine pools. Selective inhibition of key enzymes in this pathway, e.g., using DFMO and/or SAM486, reduces tumorigenesis and synergizes with chemotherapy to regress tumors in pre-clinical models. Here we review the potential clinical application of these and additional polyamine-depletion agents to neuroblastoma and other advanced cancers in which MYC is operative. PMID:19789308
Genetic and biochemical analysis of protozoal polyamine transporters.
Hasne, Marie-Pierre; Ullman, Buddy
2011-01-01
Polyamines are aliphatic polycations that function in key cellular processes such as growth, differentiation, and macromolecular biosynthesis. Intracellular polyamines pools are maintained from de novo synthesis and from transport of polyamines from the extracellular milieu. This acquisition of exogenous polyamines is mediated by cell surface transporter proteins. Protozoan parasites are the etiologic agents of a plethora of devastating and often fatal diseases in humans and their domestic animals. These pathogens accommodate de novo and/or salvage mechanisms for polyamine acquisition. Because of its therapeutic relevance, the polyamine biosynthetic pathway has been thoroughly investigated in many genera of protozoan parasites, but the polyamine permeation pathways have generally been ignored. Our group has now identified at the molecular level polyamine transporters from two species of protozoan parasites, Leishmania major and Trypanosoma cruzi, characterized these polytopic proteins with respect to ligand specificities and affinities, and determined the subcellular environments in which these transporters reside.
Shi, Haitao; Ye, Tiantian; Chan, Zhulong
2013-11-01
Polyamines conferred enhanced abiotic stress tolerance in multiple plant species. However, the effect of polyamines on abiotic stress and physiological change in bermudagrass, the most widely used warm-season turfgrasses, are unknown. In this study, pretreatment of exogenous polyamine conferred increased salt and drought tolerances in bermudagrass. Comparative proteomic analysis was performed to further investigate polyamines mediated responses, and 36 commonly regulated proteins by at least two types of polyamines in bermudagrass were successfully identified, including 12 proteins with increased level, 20 proteins with decreased level and other 4 specifically expressed proteins. Among them, proteins involved in electron transport and energy pathways were largely enriched, and nucleoside diphosphate kinase (NDPK) and three antioxidant enzymes were extensively regulated by polyamines. Dissection of reactive oxygen species (ROS) levels indicated that polyamine-derived H2O2 production might play dual roles under abiotic stress conditions. Moreover, accumulation of osmolytes was also observed after application of exogenous polyamines, which is consistent with proteomics results that several proteins involved in carbon fixation pathway were mediated commonly by polyamines pretreatment. Taken together, we proposed that polyamines could activate multiple pathways that enhance bermudagrass adaption to salt and drought stresses. These findings might be applicable for genetically engineering of grasses and crops to improve stress tolerance.
Basu, Hirak S.; Thompson, Todd A.; Church, Dawn R.; Clower, Cynthia C.; Mehraein-Ghomi, Farideh; Amlong, Corey A.; Martin, Christopher T.; Woster, Patrick M.; Lindstrom, Mary J.; Wilding, George
2009-01-01
High levels of reactive oxygen species (ROS) present in human prostate epithelia are an important etiological factor in prostate cancer (CaP) occurrence, recurrence and progression. Androgen induces ROS production in the prostate by a yet unknown mechanism. Here, to the best of our knowledge, we report for the first time that androgen induces an overexpression of spermidine/spermine N1-acetyltransferase (SSAT), the rate-limiting enzyme in the polyamine oxidation pathway. As prostatic epithelia produce a large excess of polyamines, the androgen-induced polyamine oxidation that produces H2O2 could be a major reason for the high ROS levels in the prostate epithelia. A small molecule polyamine oxidase inhibitor N,N'-butanedienyl butanediamine (MDL 72,527 or CPC-200) effectively blocks androgen-induced ROS production in human CaP cells as well as significantly delays CaP progression and death in animals developing spontaneous CaP. These data demonstrate that polyamine oxidation is not only a major pathway for ROS production in prostate, but inhibiting this pathway also successfully delays prostate cancer progression. PMID:19773450
A perspective of polyamine metabolism.
Wallace, Heather M; Fraser, Alison V; Hughes, Alun
2003-01-01
Polyamines are essential for the growth and function of normal cells. They interact with various macromolecules, both electrostatically and covalently and, as a consequence, have a variety of cellular effects. The complexity of polyamine metabolism and the multitude of compensatory mechanisms that are invoked to maintain polyamine homoeostasis argue that these amines are critical to cell survival. The regulation of polyamine content within cells occurs at several levels, including transcription and translation. In addition, novel features such as the +1 frameshift required for antizyme production and the rapid turnover of several of the enzymes involved in the pathway make the regulation of polyamine metabolism a fascinating subject. The link between polyamine content and human disease is unequivocal, and significant success has been obtained in the treatment of a number of parasitic infections. Targeting the polyamine pathway as a means of treating cancer has met with limited success, although the development of drugs such as DFMO (alpha-difluoromethylornithine), a rationally designed anticancer agent, has revolutionized our understanding of polyamine function in cell growth and provided 'proof of concept' that influencing polyamine metabolism and content within tumour cells will prevent tumour growth. The more recent development of the polyamine analogues has been pivotal in advancing our understanding of the necessity to deplete all three polyamines to induce apoptosis in tumour cells. The current thinking is that the polyamine inhibitors/analogues may also be useful agents in the chemoprevention of cancer and, in this area, we may yet see a revival of DFMO. The future will be in adopting a functional genomics approach to identifying polyamine-regulated genes linked to either carcinogenesis or apoptosis. PMID:13678416
Basu, Hirak S; Thompson, Todd A; Church, Dawn R; Clower, Cynthia C; Mehraein-Ghomi, Farideh; Amlong, Corey A; Martin, Christopher T; Woster, Patrick M; Lindstrom, Mary J; Wilding, George
2009-10-01
High levels of reactive oxygen species (ROS) present in human prostate epithelia are an important etiologic factor in prostate cancer (CaP) occurrence, recurrence, and progression. Androgen induces ROS production in the prostate by a yet unknown mechanism. Here, to the best of our knowledge, we report for the first time that androgen induces an overexpression of spermidine/spermine N1-acetyltransferase, the rate-limiting enzyme in the polyamine oxidation pathway. As prostatic epithelia produce a large excess of polyamines, the androgen-induced polyamine oxidation that produces H2O2 could be a major reason for the high ROS levels in the prostate epithelia. A small molecule polyamine oxidase inhibitor N,N'-butanedienyl butanediamine (MDL 72,527 or CPC-200) effectively blocks androgen-induced ROS production in human CaP cells, as well as significantly delays CaP progression and death in animals developing spontaneous CaP. These data show that polyamine oxidation is not only a major pathway for ROS production in prostate, but inhibiting this pathway also successfully delays CaP progression.
Molecular Mechanisms Underlying γ-Aminobutyric Acid (GABA) Accumulation in Giant Embryo Rice Seeds.
Zhao, Guo-Chao; Xie, Mi-Xue; Wang, Ying-Cun; Li, Jian-Yue
2017-06-21
To uncover the molecular mechanisms underlying GABA accumulation in giant embryo rice seeds, we analyzed the expression levels of GABA metabolism genes and contents of GABA and GABA metabolic intermediates in developing grains and germinated brown rice of giant embryo rice 'Shangshida No. 5' and normal embryo rice 'Chao2-10' respectively. In developing grains, the higher GABA contents in 'Shangshida No. 5' were accompanied with upregulation of gene transcripts and intermediate contents in the polyamine pathway and downregulation of GABA catabolic gene transcripts, as compared with those in 'Chao2-10'. In germinated brown rice, the higher GABA contents in 'Shangshida No. 5' were parallel with upregulation of OsGAD and polyamine pathway gene transcripts and Glu and polyamine pathway intermediate contents and downregulation of GABA catabolic gene transcripts. These results are the first to indicate that polyamine pathway and GABA catabolic genes play a crucial role in GABA accumulation in giant embryo rice seeds.
Agmatine: at the crossroads of the arginine pathways.
Satriano, Joseph
2003-12-01
In acute inflammatory responses, such as wound healing and glomerulonephritis, arginine is the precursor for production of the cytostatic molecule nitric oxide (NO) and the pro-proliferative polyamines. NO is an early phase response whereas increased generation of polyamines is requisite for the later, repair phase response. The temporal switch of arginine as a substrate for the inducible nitric oxide synthase (iNOS)/NO axis to arginase/ornithine decarboxylase (ODC)/polyamine axis is subject to regulation by inflammatory cytokines as well as interregulation by the arginine metabolites themselves. Herein we describe the capacity of another arginine pathway, the metabolism of arginine to agmatine by arginine decarboxylase (ADC), to aid in this interregulation. Agmatine is an antiproliferative molecule due to its suppressive effects on intracellular polyamine levels, whereas the aldehyde metabolite of agmatine is a potent inhibitor of iNOS. We propose that the catabolism of agmatine to its aldehyde metabolite may act as a gating mechanism at the transition from the iNOS/NO axis to the arginase/ODC/polyamine axis. Thus, agmatine has the potential to serve in the coordination of the early and repair phase pathways of arginine in inflammation.
Novel Occurrence of Uncommon Polyamines in Higher Plants 1
Kuehn, Glenn D.; Rodriguez-Garay, Benjamin; Bagga, Suman; Phillips, Gregory C.
1990-01-01
Diamines and polyamines are ubiquitous components of living cells, and apparently are involved in numerous cellular and physiological processes. Certain “uncommon” polyamines have limited distribution in nature and have been associated primarily with organisms adapted to extreme environments, although the precise function of these polyamines in such organisms is unknown. This article summarizes current knowledge regarding the occurrence in higher plants of the uncommon polyamines related to and including norspermidine and norspermine. A putative biosynthetic pathway to account for the occurrences of these uncommon polyamines in higher plants is presented, with a summary of the supporting evidence indicating the existence of the requisite enzymatic activities in alfalfa, Medicago sativa L. PMID:16667862
Shaw, Frances L.; Elliott, Katherine A.; Kinch, Lisa N.; Fuell, Christine; Phillips, Margaret A.; Michael, Anthony J.
2010-01-01
Polyamines are small flexible organic polycations found in almost all cells. They likely existed in the last universal common ancestor of all extant life, and yet relatively little is understood about their biological function, especially in bacteria and archaea. Unlike eukaryotes, where the predominant polyamine is spermidine, bacteria may contain instead an alternative polyamine, sym-homospermidine. We demonstrate that homospermidine synthase (HSS) has evolved vertically, primarily in the α-Proteobacteria, but enzymatically active, diverse HSS orthologues have spread by horizontal gene transfer to other bacteria, bacteriophage, archaea, eukaryotes, and viruses. By expressing diverse HSS orthologues in Escherichia coli, we demonstrate in vivo the production of co-products diaminopropane and N1-aminobutylcadaverine, in addition to sym-homospermidine. We show that sym-homospermidine is required for normal growth of the α-proteobacterium Rhizobium leguminosarum. However, sym-homospermidine can be replaced, for growth restoration, by the structural analogues spermidine and sym-norspermidine, suggesting that the symmetrical or unsymmetrical form and carbon backbone length are not critical for polyamine function in growth. We found that the HSS enzyme evolved from the alternative spermidine biosynthetic pathway enzyme carboxyspermidine dehydrogenase. The structure of HSS is related to lysine metabolic enzymes, and HSS and carboxyspermidine dehydrogenase evolved from the aspartate family of pathways. Finally, we show that other bacterial phyla such as Cyanobacteria and some α-Proteobacteria synthesize sym-homospermidine by an HSS-independent pathway, very probably based on deoxyhypusine synthase orthologues, similar to the alternative homospermidine synthase found in some plants. Thus, bacteria can contain alternative biosynthetic pathways for both spermidine and sym-norspermidine and distinct alternative pathways for sym-homospermidine. PMID:20194510
Schroll, Casper; Christensen, Jens P; Christensen, Henrik; Pors, Susanne E; Thorndahl, Lotte; Jensen, Peter R; Olsen, John E; Jelsbak, Lotte
2014-05-14
Serovars of Salmonella enterica exhibit different host-specificities where some have broad host-ranges and others, like S. Gallinarum and S. Typhi, are host-specific for poultry and humans, respectively. With the recent availability of whole genome sequences it has been reported that host-specificity coincides with accumulation of pseudogenes, indicating adaptation of host-restricted serovars to their narrow niches. Polyamines are small cationic amines and in Salmonella they can be synthesized through two alternative pathways directly from l-ornithine to putrescine and from l-arginine via agmatine to putrescine. The first pathway is not active in S. Gallinarum and S. Typhi, and this prompted us to investigate the importance of polyamines for virulence in S. Gallinarum. Bioinformatic analysis of all sequenced genomes of Salmonella revealed that pseudogene formation of the speC gene was exclusive for S. Typhi and S. Gallinarum and happened through independent events. The remaining polyamine biosynthesis pathway was found to be essential for oral infection with S. Gallinarum since single and double mutants in speB and speE, encoding the pathways from agmatine to putrescine and from putrescine to spermidine, were attenuated. In contrast, speB was dispensable after intraperitoneal challenge, suggesting that putrescine was less important for the systemic phase of the disease. In support of this hypothesis, a ΔspeE;ΔpotCD mutant, unable to synthesize and import spermidine, but with retained ability to import and synthesize putrescine, was attenuated after intraperitoneal infection. We therefore conclude that polyamines are essential for virulence of S. Gallinarum. Furthermore, our results point to distinct roles for putrescine and spermidine during systemic infection. Copyright © 2014 Elsevier B.V. All rights reserved.
Yi Lasanajak; Rakesh Minocha; Subhash C. Minocha; Ravinder Goyal; Tahira Fatima; Avtar K. Handa; Autar K. Mattoo
2014-01-01
S-adenosylmethionine (SAM), a major substrate in 1-C metabolism is a common precursor in the biosynthetic pathways of polyamines and ethylene, two important plant growth regulators, which exhibit opposing developmental effects, especially during fruit ripening. However, the flux of various substrates including SAM into the two competing pathways in...
Generation of EMS-Mutagenized Populations of Arabidopsis thaliana for Polyamine Genetics.
Atanasov, Kostadin E; Liu, Changxin; Tiburcio, Antonio F; Alcázar, Rubén
2018-01-01
In the recent years, genetic engineering of polyamine biosynthetic genes has provided evidence for their involvement in plant stress responses and different aspects of plant development. Such approaches are being complemented with the use of reverse genetics, in which mutants affected on a particular trait, tightly associated with polyamines, are isolated and the causal genes mapped. Reverse genetics enables the identification of novel genes in the polyamine pathway, which may be involved in downstream signaling, transport, homeostasis, or perception. Here, we describe a basic protocol for the generation of ethyl methanesulfonate (EMS) mutagenized populations of Arabidopsis thaliana for its use in reverse genetics applied to polyamines.
Polyamine pathway inhibition as a novel therapeutic approach to treating neuroblastoma
Gamble, Laura D.; Hogarty, Michael D.; Liu, Xueyuan; Ziegler, David S.; Marshall, Glenn; Norris, Murray D.; Haber, Michelle
2012-01-01
Polyamines are highly regulated essential cations that are elevated in rapidly proliferating tissues, including diverse cancers. Expression analyses in neuroblastomas suggest that up-regulation of polyamine pro-synthetic enzymes and down-regulation of catabolic enzymes is associated with poor prognosis. Polyamine sufficiency may be required for MYCN oncogenicity in MYCN amplified neuroblastoma, and targeting polyamine homeostasis may therefore provide an attractive therapeutic approach. ODC1, an oncogenic MYCN target, is rate-limiting for polyamine synthesis, and is overexpressed in many cancers including neuroblastoma. Inhibition of ODC1 by difluoromethylornithine (DFMO) decreased tumor penetrance in TH-MYCN mice treated pre-emptively, and extended survival and synergized with chemotherapy in treating established tumors in both TH-MYCN and xenograft models. Efforts to augment DFMO activity, or otherwise maximally reduce polyamine levels, are focused on antagonizing polyamine uptake or augmenting polyamine export or catabolism. Since polyamine inhibition appears to be clinically well tolerated, these approaches, particularly when combined with chemotherapy, have great potential for improving neuroblastoma outcome in both MYCN amplified and non-MYCN amplified neuroblastomas. PMID:23181218
Biotechnological production of polyamines by bacteria: recent achievements and future perspectives.
Schneider, Jens; Wendisch, Volker F
2011-07-01
In Bacteria, the pathways of polyamine biosynthesis start with the amino acids L-lysine, L-ornithine, L-arginine, or L-aspartic acid. Some of these polyamines are of special interest due to their use in the production of engineering plastics (e.g., polyamides) or as curing agents in polymer applications. At present, the polyamines for industrial use are mainly synthesized on chemical routes. However, since a commercial market for polyamines as well as an industry for the fermentative production of amino acid exist, and since bacterial strains overproducing the polyamine precursors L-lysine, L-ornithine, and L-arginine are known, it was envisioned to engineer these amino acid-producing strains for polyamine production. Only recently, researchers have investigated the potential of amino acid-producing strains of Corynebacterium glutamicum and Escherichia coli for polyamine production. This mini-review illustrates the current knowledge of polyamine metabolism in Bacteria, including anabolism, catabolism, uptake, and excretion. The recent advances in engineering the industrial model bacteria C. glutamicum and E. coli for efficient production of the most promising polyamines, putrescine (1,4-diaminobutane), and cadaverine (1,5-diaminopentane), are discussed in more detail.
Barone, Sharon L.; Xu, Jie; Steinbergs, Nora; Schuster, Rebecca; Lentsch, Alex B.; Amlal, Hassane; Wang, Jiang; Casero, Robert A.; Soleimani, Manoocher
2012-01-01
Activation of spermine/spermidine-N1-acetyltransferase (SSAT) leads to DNA damage and growth arrest in mammalian cells, and its ablation reduces the severity of ischemic and endotoxic injuries. Here we have examined the role of SSAT in the pathogenesis of toxic liver injury caused by carbon tetrachloride (CCl4). The expression and activity of SSAT increase in the liver subsequent to CCl4 administration. Furthermore, the early liver injury after CCl4 treatment was significantly attenuated in hepatocyte-specific SSAT knockout mice (Hep-SSAT-Cko) compared with wild-type (WT) mice as determined by the reduced serum alanine aminotransferase levels, decreased hepatic lipid peroxidation, and less severe liver damage. Cytochrome P450 2e1 levels remained comparable in both genotypes, suggesting that SSAT deficiency does not affect the metabolism of CCl4. Hepatocyte-specific deficiency of SSAT also modulated the induction of cytokines involved in inflammation and repair as well as leukocyte infiltration. In addition, Noxa and activated caspase 3 levels were elevated in the livers of WT compared with Hep-SSAT-Cko mice. Interestingly, the onset of cell proliferation was significantly more robust in the WT compared with Hep-SSAT Cko mice. The inhibition of polyamine oxidases protected the animals against CCl4-induced liver injury. Our studies suggest that while the abrogation of polyamine back conversion or inhibition of polyamine oxidation attenuate the early injury, they may delay the onset of hepatic regeneration. PMID:22723264
Zahedi, Kamyar; Barone, Sharon L; Xu, Jie; Steinbergs, Nora; Schuster, Rebecca; Lentsch, Alex B; Amlal, Hassane; Wang, Jiang; Casero, Robert A; Soleimani, Manoocher
2012-09-01
Activation of spermine/spermidine-N(1)-acetyltransferase (SSAT) leads to DNA damage and growth arrest in mammalian cells, and its ablation reduces the severity of ischemic and endotoxic injuries. Here we have examined the role of SSAT in the pathogenesis of toxic liver injury caused by carbon tetrachloride (CCl(4)). The expression and activity of SSAT increase in the liver subsequent to CCl(4) administration. Furthermore, the early liver injury after CCl(4) treatment was significantly attenuated in hepatocyte-specific SSAT knockout mice (Hep-SSAT-Cko) compared with wild-type (WT) mice as determined by the reduced serum alanine aminotransferase levels, decreased hepatic lipid peroxidation, and less severe liver damage. Cytochrome P450 2e1 levels remained comparable in both genotypes, suggesting that SSAT deficiency does not affect the metabolism of CCl(4). Hepatocyte-specific deficiency of SSAT also modulated the induction of cytokines involved in inflammation and repair as well as leukocyte infiltration. In addition, Noxa and activated caspase 3 levels were elevated in the livers of WT compared with Hep-SSAT-Cko mice. Interestingly, the onset of cell proliferation was significantly more robust in the WT compared with Hep-SSAT Cko mice. The inhibition of polyamine oxidases protected the animals against CCl(4)-induced liver injury. Our studies suggest that while the abrogation of polyamine back conversion or inhibition of polyamine oxidation attenuate the early injury, they may delay the onset of hepatic regeneration.
Lepri, O.; Bassie, L.; Thu-Hang, P.; Christou, P.; Capell, T.
2002-09-01
We used the polyamine biosynthetic pathway and rice as a relevant model to understand the genetic basis of variation in endogenous levels of metabolites and key enzymes involved in the pathway. Wild-type tissues and also tissues containing a commonly used selectable marker gene were employed. We detected a wide variation in levels of arginine decarboxylase activity and in the three polyamines, putrescine, spermidine and spermine, in different tissues and varieties, but this was not dependent on the presence of the selectable marker. A more-extensive profile of enzyme activities (ADC, ODC, SAMDC, DAO and PAO) and polyamine levels in different tissues was generated in two different varieties. Our results indicate that genetic background is important in terms of the basal levels of metabolites and enzyme activity, particularly in situations in which we aim to engineer metabolic pathways that are also encoded by homologous endogenous genes. We did not find any evidence that the presence of a selectable marker in any way influences enzyme activity or metabolite levels.
Fidanzi-Dugas, Chloë; Liagre, Bertrand; Chemin, Guillaume; Perraud, Aurélie; Carrion, Claire; Couquet, Claude-Yves; Granet, Robert; Sol, Vincent; Léger, David Yannick
2017-07-01
Photodynamic therapy, using porphyrins as photosensitizers (PS), has been approved in treatment of several solid tumors. However, commonly used PS induce death but also resistance pathways in cancer cells and an alteration of surrounding normal tissues. Because polyamines (PA) are actively accumulated in cancer cells by the Polyamine Transport System (PTS), they may enable PS to specifically target cancer cells. Here, we investigated whether new protoporphyrin IX-polyamine derivatives were effective PS against prostate cancer and whether PA increased PDT specificity after 630nm irradiation. CHO and CHO-MG cells (differing in their PTS activity) were used to assess efficacy of polyamine vectorization. MTT assays were performed on human prostate non-malignant (RWPE-1) and malignant (PC-3, DU 145 and LNCaP) cell lines to test PS phototoxicity. ROS generation, DNA fragmentation and cell signalling were assessed by ELISA/EIA, western-blots and gel shift assays. Finally, PS effects were studied on tumor growth in nude mice. Our PS were more effective on cancer cells compared to non-malignant cells and more effective than PpIX alone. PpIX-PA generated ROS production involved in induction of apoptotic intrinsic pathways. Different pathways involved in apoptosis resistance were studied: PS inhibited Bcl-2, Akt, and NF-κB but activated p38/COX-2/PGE 2 pathways which were not implicated in apoptosis resistance in our model. In vivo experiments showed PpIX-PA efficacy was greater than results obtained with PpIX. All together, our results showed that PpIX-PA exerted its maximum effects without activating resistance pathways and appears to be a good candidate for prostate cancer PDT treatment. Copyright © 2017 Elsevier B.V. All rights reserved.
Role of Polyamines in Asthma Pathophysiology
2018-01-01
Asthma is a complex disease of airways, where the interactions of immune and structural cells result in disease outcomes with airway remodeling and airway hyper-responsiveness. Polyamines, which are small-sized, natural super-cations, interact with negatively charged intracellular macromolecules, and altered levels of polyamines and their interactions have been associated with different pathological conditions including asthma. Elevated levels of polyamines have been reported in the circulation of asthmatic patients as well as in the lungs of a murine model of asthma. In various studies, polyamines were found to potentiate the pathogenic potential of inflammatory cells, such as mast cells and granulocytes (eosinophils and neutrophils), by either inducing the release of their pro-inflammatory mediators or prolonging their life span. Additionally, polyamines were crucial in the differentiation and alternative activation of macrophages, which play an important role in asthma pathology. Importantly, polyamines cause airway smooth muscle contraction and thus airway hyper-responsiveness, which is the key feature in asthma pathophysiology. High levels of polyamines in asthma and their active cellular and macromolecular interactions indicate the importance of the polyamine pathway in asthma pathogenesis; therefore, modulation of polyamine levels could be a suitable approach in acute and severe asthma management. This review summarizes the possible roles of polyamines in different pathophysiological features of asthma. PMID:29316647
ODC1 is a critical determinant of MYCN oncogenesis and a therapeutic target in neuroblastoma
Hogarty, Michael D.; Norris, Murray D.; Davis, Kim; Liu, Xueyuan; Evageliou, Nicholas F.; Hayes, Candace S.; Pawel, Bruce; Guo, Rong; Zhao, Huaqing; Sekyere, Eric; Keating, Joanna; Thomas, Wayne; Cheng, Ngan Ching; Murray, Jayne; Smith, Janice; Sutton, Rosemary; Venn, Nicola; London, Wendy B.; Buxton, Allan; Gilmour, Susan K.; Marshall, Glenn M; Haber, Michelle
2008-01-01
Neuroblastoma is a frequently lethal childhood tumor in which MYC gene deregulation, commonly as MYCN amplification, portends poor outcome. Identifying the requisite biopathways downstream of MYC may provide therapeutic opportunities. We used transcriptome analyses to show that MYCN-amplified neuroblastomas have co-ordinately deregulated myriad polyamine enzymes (including ODC1, SRM, SMS, AMD1, OAZ2, and SMOX) to enhance polyamine biosynthesis. High-risk tumors without MYCN amplification also overexpress ODC1, the rate-limiting enzyme in polyamine biosynthesis, when compared with lower risk tumors, suggesting this pathway may be pivotal. Indeed, elevated ODC1 (independent of MYCN amplification) was associated with reduced survival in a large independent neuroblastoma cohort. As polyamines are essential for cell survival and linked to cancer progression, we studied polyamine antagonism to test for metabolic dependence on this pathway in neuroblastoma. The Odc inhibitor α-difluoromethylornithine (DFMO) inhibited neuroblast proliferation in vitro and suppressed oncogenesis in vivo. DFMO treatment of neuroblastoma-prone genetically-engineered mice (TH-MYCN GEM) extended tumor latency and survival in homozygous mice, and prevented oncogenesis in hemizygous mice. In the latter, transient Odc ablation permanently prevented tumor onset consistent with a time-limited window for embryonal tumor initiation. Importantly, we show that DFMO augments anti-tumor efficacy of conventional cytotoxics in vivo. This work implicates polyamine biosynthesis as an arbiter of MYCN oncogenesis and demonstrates initial efficacy for polyamine depletion strategies in neuroblastoma, a strategy that may have utility for this and other MYC-driven embryonal tumors. PMID:19047152
ODC1 is a critical determinant of MYCN oncogenesis and a therapeutic target in neuroblastoma.
Hogarty, Michael D; Norris, Murray D; Davis, Kimberly; Liu, Xueyuan; Evageliou, Nicholas F; Hayes, Candace S; Pawel, Bruce; Guo, Rong; Zhao, Huaqing; Sekyere, Eric; Keating, Joanna; Thomas, Wayne; Cheng, Ngan Ching; Murray, Jayne; Smith, Janice; Sutton, Rosemary; Venn, Nicola; London, Wendy B; Buxton, Allen; Gilmour, Susan K; Marshall, Glenn M; Haber, Michelle
2008-12-01
Neuroblastoma is a frequently lethal childhood tumor in which MYC gene deregulation, commonly as MYCN amplification, portends poor outcome. Identifying the requisite biopathways downstream of MYC may provide therapeutic opportunities. We used transcriptome analyses to show that MYCN-amplified neuroblastomas have coordinately deregulated myriad polyamine enzymes (including ODC1, SRM, SMS, AMD1, OAZ2, and SMOX) to enhance polyamine biosynthesis. High-risk tumors without MYCN amplification also overexpress ODC1, the rate-limiting enzyme in polyamine biosynthesis, when compared with lower-risk tumors, suggesting that this pathway may be pivotal. Indeed, elevated ODC1 (independent of MYCN amplification) was associated with reduced survival in a large independent neuroblastoma cohort. As polyamines are essential for cell survival and linked to cancer progression, we studied polyamine antagonism to test for metabolic dependence on this pathway in neuroblastoma. The Odc inhibitor alpha-difluoromethylornithine (DFMO) inhibited neuroblast proliferation in vitro and suppressed oncogenesis in vivo. DFMO treatment of neuroblastoma-prone genetically engineered mice (TH-MYCN) extended tumor latency and survival in homozygous mice and prevented oncogenesis in hemizygous mice. In the latter, transient Odc ablation permanently prevented tumor onset consistent with a time-limited window for embryonal tumor initiation. Importantly, we show that DFMO augments antitumor efficacy of conventional cytotoxics in vivo. This work implicates polyamine biosynthesis as an arbiter of MYCN oncogenesis and shows initial efficacy for polyamine depletion strategies in neuroblastoma, a strategy that may have utility for this and other MYC-driven embryonal tumors.
Targeting polyamine metabolism for cancer therapy and prevention
Murray-Stewart, Tracy R.; Woster, Patrick M.; Casero, Robert A.
2017-01-01
The chemically simple, biologically complex eukaryotic polyamines, spermidine and spermine, are positively charged alkylamines involved in many crucial cellular processes. Along with their diamine precursor putrescine, their normally high intracellular concentrations require fine attenuation by multiple regulatory mechanisms to keep these essential molecules within strict physiologic ranges. Since the metabolism of and requirement for polyamines are frequently dysregulated in neoplastic disease, the metabolic pathway and functions of polyamines provide rational drug targets; however, these targets have been difficult to exploit for chemotherapy. It is the goal of this article to review the latest findings in the field that demonstrate the potential utility of targeting the metabolism and function of polyamines as strategies for both chemotherapy and, possibly more importantly, chemoprevention. PMID:27679855
2010-01-01
Background The fungal pathogen Fusarium graminearum causes Fusarium Head Blight (FHB) disease on wheat which can lead to trichothecene mycotoxin (e.g. deoxynivalenol, DON) contamination of grain, harmful to mammalian health. DON is produced at low levels under standard culture conditions when compared to plant infection but specific polyamines (e.g. putrescine and agmatine) and amino acids (e.g. arginine and ornithine) are potent inducers of DON by F. graminearum in axenic culture. Currently, host factors that promote mycotoxin synthesis during FHB are unknown, but plant derived polyamines could contribute to DON induction in infected heads. However, the temporal and spatial accumulation of polyamines and amino acids in relation to that of DON has not been studied. Results Following inoculation of susceptible wheat heads by F. graminearum, DON accumulation was detected at two days after inoculation. The accumulation of putrescine was detected as early as one day following inoculation while arginine and cadaverine were also produced at three and four days post-inoculation. Transcripts of ornithine decarboxylase (ODC) and arginine decarboxylase (ADC), two key biosynthetic enzymes for putrescine biosynthesis, were also strongly induced in heads at two days after inoculation. These results indicated that elicitation of the polyamine biosynthetic pathway is an early response to FHB. Transcripts for genes encoding enzymes acting upstream in the polyamine biosynthetic pathway as well as those of ODC and ADC, and putrescine levels were also induced in the rachis, a flower organ supporting DON production and an important route for pathogen colonisation during FHB. A survey of 24 wheat genotypes with varying responses to FHB showed putrescine induction is a general response to inoculation and no correlation was observed between the accumulation of putrescine and infection or DON accumulation. Conclusions The activation of the polyamine biosynthetic pathway and putrescine in infected heads prior to detectable DON accumulation is consistent with a model where the pathogen exploits the generic host stress response of polyamine synthesis as a cue for production of trichothecene mycotoxins during FHB disease. However, it is likely that this mechanism is complicated by other factors contributing to resistance and susceptibility in diverse wheat genetic backgrounds. PMID:21192794
Ferioli, M E; Armanni, A
2003-01-01
To extend the knowledge on the role of polyamine oxidase in thymus physiology, we evaluated the in vivo effect of the polyamine biosynthetic pathway inhibitor mitoguazone. The drug markedly and permanently decreased the enzyme activity in the organ, in which the level of putrescine also decreased at the later times observed. A byproduct of the reaction catalyzed by polyamine oxidase is hydrogen peroxide, a well known inducer of apoptosis. The decrease in polyamine oxidase activity, with the consequent decrease in hydrogen peroxide production, is correlated with a positive effect on thymus physiology. Since mitoguazone has been successfully employed in patients with AIDS-related diseases, in which the reconstitution of the immune function is a favorable prognostic index, we hypothesized that mitoguazone may have the thymus as target organ, and that the decrease in polyamine oxidase activity may have a role in the positive effect of the drug.
McKenna, James; Kapfhamer, David; Kinchen, Jason M; Wasek, Brandi; Dunworth, Matthew; Murray-Stewart, Tracy; Bottiglieri, Teodoro; Casero, Robert A; Gambello, Michael J
2018-06-15
Tuberous sclerosis complex (TSC) is an autosomal dominant neurodevelopmental disorder and the quintessential disorder of mechanistic Target of Rapamycin Complex 1 (mTORC1) dysregulation. Loss of either causative gene, TSC1 or TSC2, leads to constitutive mTORC1 kinase activation and a pathologically anabolic state of macromolecular biosynthesis. Little is known about the organ-specific metabolic reprogramming that occurs in TSC-affected organs. Using a mouse model of TSC in which Tsc2 is disrupted in radial glial precursors and their neuronal and glial descendants, we performed an unbiased metabolomic analysis of hippocampi to identify Tsc2-dependent metabolic changes. Significant metabolic reprogramming was found in well-established pathways associated with mTORC1 activation, including redox homeostasis, glutamine/tricarboxylic acid cycle, pentose and nucleotide metabolism. Changes in two novel pathways were identified: transmethylation and polyamine metabolism. Changes in transmethylation included reduced methionine, cystathionine, S-adenosylmethionine (SAM-the major methyl donor), reduced SAM/S-adenosylhomocysteine ratio (cellular methylation potential), and elevated betaine, an alternative methyl donor. These changes were associated with alterations in SAM-dependent methylation pathways and expression of the enzymes methionine adenosyltransferase 2A and cystathionine beta synthase. We also found increased levels of the polyamine putrescine due to increased activity of ornithine decarboxylase, the rate-determining enzyme in polyamine synthesis. Treatment of Tsc2+/- mice with the ornithine decarboxylase inhibitor α-difluoromethylornithine, to reduce putrescine synthesis dose-dependently reduced hippocampal astrogliosis. These data establish roles for SAM-dependent methylation reactions and polyamine metabolism in TSC neuropathology. Importantly, both pathways are amenable to nutritional or pharmacologic therapy.
Inhibitors of polyamine metabolism: review article.
Wallace, H M; Fraser, A V
2004-07-01
The identification of increased polyamine concentrations in a variety of diseases from cancer and psoriasis to parasitic infections has led to the hypothesis that manipulation of polyamine metabolism is a realistic target for therapeutic or preventative intervention in the treatment of certain diseases. The early development of polyamine biosynthetic single enzyme inhibitors such as alpha-difluoromethylornithine (DFMO) and methylglyoxal bis(guanylhydrazone) showed some interesting early promise as anticancer drugs, but ultimately failed in vivo. Despite this, DFMO is currently in use as an effective anti-parasitic agent and has recently also been shown to have further potential as a chemopreventative agent in colorectal cancer. The initial promise in vitro led to the development and testing of other potential inhibitors of the pathway namely the polyamine analogues. The analogues have met with greater success than the single enzyme inhibitors possibly due to their multiple targets. These include down regulation of polyamine biosynthesis through inhibition of ornithine decarboxylase and S-adenosylmethionine decarboxylase and decreased polyamine uptake. This coupled with increased activity of the catabolic enzymes, polyamine oxidase and spermidine/spermine N1-acetyltransferase, and increased polyamine export has made the analogues more effective in depleting polyamine pools. Recently, the identification of a new oxidase (PAO-h1/SMO) in polyamine catabolism and evidence of induction of both PAO and PAO-h1/SMO in response to polyamine analogue treatment, suggests the analogues may become an important part of future chemotherapeutic and/or chemopreventative regimens.
Ferioli, M E; Bottone, M G; Soldani, C; Pellicciari, C
2004-11-01
The suggestion has been made that polyamines may be involved in the control of cell death, since exceedingly high or low levels induce apoptosis in different cell systems. For a deeper insight into the relationship between apoptosis and polyamine metabolism, we investigated in vitro the effect on rat thymocytes of mitoguazone (MGBG, which inhibits S-adenosylmethionine decarboxylase, i.e. a key enzyme in the polyamine biosynthetic pathway). Thymocytes were selected as an especially suitable model system, since they undergo spontaneous apoptosis in vivo and can be easily induced to apoptose in vitro by etoposide, used here as an apoptogenic agent. MGBG protected thymocytes from both spontaneous and drug-induced apoptosis, and this protective effect was associated with a decrease in polyamine oxidase activity and total polyamine levels.
Kanika, Nirmala Devi; Tar, Moses; Tong, Yuehong; Kuppam, Dwaraka Srinivasa Rao; Melman, Arnold; Davies, Kelvin Paul
2009-10-01
Intracorporal injection of plasmids encoding opiorphins into retired breeder rats can result in animals developing a priapic-like condition. Microarray analysis demonstrated that following intracorporal gene transfer of plasmids expressing opiorphins the most significantly upregulated gene in corporal tissue was the ornithine decarboxylase gene (ODC). Quantitative RT-PCR confirmed the upregulation of ODC, as well as other genes involved in polyamine synthesis, such as arginase-I and -II, polyamine oxidase, spermidine synthase, spermidine acetyltransferase (SAT), and S-adenosylmethionine decarboxylase. Western blot analysis demonstrated upregulation of arginase-I and -II, ODC, and SAT at the protein level. Levels of the polyamine putrescine were upregulated in animals treated with opiorphin-expressing plasmids compared with controls. A direct role for the upregulation of polyamine synthesis in the development of the priapic-like condition was supported by the observation that the ODC inhibitor 1,3-diaminopropane, when added to the drinking water of animals treated with plasmids expressing opiorphins, prevented experimental priapism. We also demonstrate that in sickle cell mice, another model of priapism, there is increased expression of the mouse opiorphin homologue in corporal tissue compared with the background strain at a life stage prior to evidence of priapism. At a life stage when there is onset of priapism, there is increased expression of the enzymes involved in polyamine synthesis (ODC and arginase-I and -II). Our results suggest that the upregulation of enzymes involved in the polyamine synthetic pathway may play a role in the development of experimental priapism and represent a target for the prevention of priapism.
Kanika, Nirmala Devi; Tar, Moses; Tong, Yuehong; Kuppam, Dwaraka Srinivasa Rao; Melman, Arnold
2009-01-01
Intracorporal injection of plasmids encoding opiorphins into retired breeder rats can result in animals developing a priapic-like condition. Microarray analysis demonstrated that following intracorporal gene transfer of plasmids expressing opiorphins the most significantly upregulated gene in corporal tissue was the ornithine decarboxylase gene (ODC). Quantitative RT-PCR confirmed the upregulation of ODC, as well as other genes involved in polyamine synthesis, such as arginase-I and -II, polyamine oxidase, spermidine synthase, spermidine acetyltransferase (SAT), and S-adenosylmethionine decarboxylase. Western blot analysis demonstrated upregulation of arginase-I and -II, ODC, and SAT at the protein level. Levels of the polyamine putrescine were upregulated in animals treated with opiorphin-expressing plasmids compared with controls. A direct role for the upregulation of polyamine synthesis in the development of the priapic-like condition was supported by the observation that the ODC inhibitor 1,3-diaminopropane, when added to the drinking water of animals treated with plasmids expressing opiorphins, prevented experimental priapism. We also demonstrate that in sickle cell mice, another model of priapism, there is increased expression of the mouse opiorphin homologue in corporal tissue compared with the background strain at a life stage prior to evidence of priapism. At a life stage when there is onset of priapism, there is increased expression of the enzymes involved in polyamine synthesis (ODC and arginase-I and -II). Our results suggest that the upregulation of enzymes involved in the polyamine synthetic pathway may play a role in the development of experimental priapism and represent a target for the prevention of priapism. PMID:19657052
Polyamine-dependent migration of retinal pigment epithelial cells.
Johnson, Dianna A; Fields, Carolyn; Fallon, Amy; Fitzgerald, Malinda E C; Viar, Mary Jane; Johnson, Leonard R
2002-04-01
Migration of retinal pigment epithelial (RPE) cells can be triggered by disruption of the RPE monolayer or injury to the neural retina. Migrating cells may re-establish a confluent monolayer, or they may invade the neural retina and disrupt visual function. The purpose of this study was to examine the role of endogenous polyamines in mechanisms of RPE migration. Endogenous polyamine levels were determined in an immortalized RPE cell line, D407, using HPLC. Activities of the two rate-limiting enzymes for polyamine synthesis, ornithine decarboxylase (ODC), and S-adenosylmethionine decarboxylase (SAMdc), were measured by liberation of ((14)CO(2))(.) Migration was assessed in confluent cultures by determining the number of cells migrating into a mechanically denuded area. All measurements were obtained both in control cultures and in cultures treated with synthesis inhibitors that deplete endogenous polyamines. Subcellular localization of endogenous polyamines was determined using a polyamine antibody. The polyamines, spermidine and spermine, as well as their precursor, putrescine, were normal constituents of RPE cells. The two rate-limiting synthetic enzymes were also present, and their activities were stimulated dramatically by addition of serum to the culture medium. Cell migration was similarly stimulated by serum exposure. When endogenous polyamines were depleted, migration was blocked. When polyamines were replenished through uptake, migration was restored. Polyamine immunoreactivity was limited to membrane patches in quiescent cells. In actively migrating and dividing cells, immunoreactivity was enhanced throughout the cytoplasm. Polyamines are essential for RPE migration. Pharmacologic manipulation of the polyamine pathway could provide a therapeutic strategy for regulating anomalous migration.
2010-01-01
Background Plasmodium falciparum, the causative agent of severe human malaria, has evolved to become resistant to previously successful antimalarial chemotherapies, most notably chloroquine and the antifolates. The prevalence of resistant strains has necessitated the discovery and development of new chemical entities with novel modes-of-action. Although much effort has been invested in the creation of analogues based on existing drugs and the screening of chemical and natural compound libraries, a crucial shortcoming in current Plasmodial drug discovery efforts remains the lack of an extensive set of novel, validated drug targets. A requirement of these targets (or the pathways in which they function) is that they prove essential for parasite survival. The polyamine biosynthetic pathway, responsible for the metabolism of highly abundant amines crucial for parasite growth, proliferation and differentiation, is currently under investigation as an antimalarial target. Chemotherapeutic strategies targeting this pathway have been successfully utilized for the treatment of Trypanosomes causing West African sleeping sickness. In order to further evaluate polyamine depletion as possible antimalarial intervention, the consequences of inhibiting P. falciparum spermidine synthase (PfSpdSyn) were examined on a morphological, transcriptomic, proteomic and metabolic level. Results Morphological analysis of P. falciparum 3D7 following application of the PfSpdSyn inhibitor cyclohexylamine confirmed that parasite development was completely arrested at the early trophozoite stage. This is in contrast to untreated parasites which progressed to late trophozoites at comparable time points. Global gene expression analyses confirmed a transcriptional arrest in the parasite. Several of the differentially expressed genes mapped to the polyamine biosynthetic and associated metabolic pathways. Differential expression of corresponding parasite proteins involved in polyamine biosynthesis was also observed. Most notably, uridine phosphorylase, adenosine deaminase, lysine decarboxylase (LDC) and S-adenosylmethionine synthetase were differentially expressed at the transcript and/or protein level. Several genes in associated metabolic pathways (purine metabolism and various methyltransferases) were also affected. The specific nature of the perturbation was additionally reflected by changes in polyamine metabolite levels. Conclusions This study details the malaria parasite's response to PfSpdSyn inhibition on the transcriptomic, proteomic and metabolic levels. The results corroborate and significantly expand previous functional genomics studies relating to polyamine depletion in this parasite. Moreover, they confirm the role of transcriptional regulation in P. falciparum, particularly in this pathway. The findings promote this essential pathway as a target for antimalarial chemotherapeutic intervention strategies. PMID:20385001
Polyamine metabolism and osmotic stress. I. Relation to protoplast viability
NASA Technical Reports Server (NTRS)
Tiburcio, A. F.; Masdeu, M. A.; Dumortier, F. M.; Galston, A. W.
1986-01-01
Cereal leaves subjected to the osmotica routinely used for protoplast isolation show a rapid increase in arginine decarboxylase activity, a massive accumulation of putrescine, and slow conversion of putrescine to the higher polyamines, spermidine and spermine (HE Flores, AW Galston 1984 Plant Physiol 75: 102). Mesophyll protoplasts from these leaves, which have a high putrescine:polyamine ratio, do not undergo sustained division. By contrast, in Nicotiana, Capsicum, Datura, Trigonella, and Vigna, dicot genera that readily regenerate plants from mesophyll protoplasts, the response of leaves to osmotic stress is opposite to that in cereals. Putrescine titer as well as arginine and ornithine decarboxylase activities decline in these osmotically stressed dicot leaves, while spermidine and spermine titers increase. Thus, the putrescine:polyamine ratio in Vigna protoplasts, which divide readily, is 4-fold lower than in oat protoplasts, which divide poorly. We suggest that this differing response of polyamine metabolism to osmotic stress may account in part for the failure of cereal mesophyll protoplasts to develop readily in vitro.
Estiarte, N; Crespo-Sempere, A; Marín, S; Sanchis, V; Ramos, A J
2017-08-01
Polyamines are essential for all living organisms as they are involved in several vital cell functions. The biosynthetic pathway of polyamines and its regulation is well established and, in this sense, the ornithine descarboxylase (ODC) enzyme acts as one of the controlling factors of the entire pathway. In this work we assessed the inhibition of the ODC with D, l-α-difluoromethylornithine (DFMO) on Alternaria alternata and we observed that fungal growth and mycotoxin production were reduced. This inhibition was not completely restored by the addition of exogenous putrescine. Actually, increasing concentrations of putrescine on the growth media negatively affected mycotoxin production, which was corroborated by the downregulation of pksJ and altR, both genes involved in mycotoxin biosynthesis. We also studied the polyamine metabolism of A. alternata with the goal of finding new targets that compromise its growth and its mycotoxin production capacity. In this sense, we tested two different polyamine analogs, AMXT-2455 and AMXT-3016, and we observed that they partially controlled A. alternata's viability in vitro and in vivo using tomato plants. Finding strategies to design new fungicide substances is becoming a matter of interest as resistance problems are emerging. Copyright © 2017. Published by Elsevier Ltd.
Thu-Hang, Pham; Bassie, Ludovic; Safwat, Gehan; Trung-Nghia, Pham; Christou, Paul; Capell, Teresa
2002-01-01
We posed the question of whether steady-state levels of the higher polyamines spermidine and spermine in plants can be influenced by overexpression of a heterologous cDNA involved in the later steps of the pathway, in the absence of any further manipulation of the two synthases that are also involved in their biosynthesis. Transgenic rice (Oryza sativa) plants engineered with the heterologous Datura stramonium S-adenosylmethionine decarboxylase (samdc) cDNA exhibited accumulation of the transgene steady-state mRNA. Transgene expression did not affect expression of the orthologous samdc gene. Significant increases in SAMDC activity translated to a direct increase in the level of spermidine, but not spermine, in leaves. Seeds recovered from a number of plants exhibited significant increases in spermidine and spermine levels. We demonstrate that overexpression of the D. stramonium samdc cDNA in transgenic rice is sufficient for accumulation of spermidine in leaves and spermidine and spermine in seeds. These findings suggest that increases in enzyme activity in one of the two components of the later parts of the pathway leading to the higher polyamines is sufficient to alter their levels mostly in seeds and, to some extent, in vegetative tissue such as leaves. Implications of our results on the design of rational approaches for the modulation of the polyamine pathway in plants are discussed in the general framework of metabolic pathway engineering. PMID:12177487
Cellular content and biosynthesis of polyamines during rooster spermatogenesis.
Oliva, R; Vidal, S; Mezquita, C
1982-01-01
The natural polyamines spermine and spermidine, and the diamine putrescine, were extracted from rooster testis cells separated by sedimentation at unit gravity, and from vas-deferens spermatozoa. The ratios spermine/DNA and spermidine/DNA were kept relatively constant throughout spermatogenesis, whereas the ratio putrescine/DNA rose in elongated spermatids. The cellular content of spermine, spermidine and putrescine decreased markedly in mature spermatozoa. Two rate-limiting enzymes in the biosynthetic pathway of polyamines, ornithine decarboxylase and S-adenosyl-L-methionine decarboxylase, showed their highest activities at the end of spermiogenesis and were not detectable in vas-deferens spermatozoa. A marked reduction in cell volume during spermiogenesis without a parallel decrease in the cellular content of polyamines suggests the possibility that the marked changes in chromatin composition and structure occurring in rooster late spermatids could take place in an ambience of high polyamine concentration. Images PLATE 1 PMID:7159401
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rastogi, R.; Davies, P.J.
The metabolism of (1,4-{sup 14}C)putrescine and (terminal methylene-{sup 3}H)spermidine was studied in the fruit pericarp (breaker stage) discs of tomato (Lycopersicon esculentum Mill.) cv Rutgers, and the metabolites identified by high performance liquid chromatography and gas chromatography-mass spectrometry. The metabolism of both putrescine and spermidine was relatively slow; in 24 hours about 15% of each amine was metabolized. The {sup 14}C label from putrescine was incorporated into spermidine, {gamma}-aminobutyric acid (GABA), glutamic acid, and a polar fraction eluting with sugars and organic acids. In the presence of gabaculine, a specific inhibitor of GABA:pyruvate transminase, the label going into glutamic acid,more » sugars and organic acids decreased by 80% while that in GABA increased about twofold, indicating that the transamination reaction is probably a major fate of GABA produced from putrescine in vivo. ({sup 3}H)Spermidine was catabolized into putrescine and {beta}-alanine. The conversion of putrescine into GABA, and that of spermidine into putrescine, suggests the presence of polyamine oxidizing enzymes in tomato pericarp tissues. The possible pathways of putrescine and spermidine metabolism are discussed.« less
Polyamines in plant physiology
NASA Technical Reports Server (NTRS)
Galston, A. W.; Sawhney, R. K.
1990-01-01
The diamine putrescine, the triamine spermidine, and the tetramine spermine are ubiquitous in plant cells, while other polyamines are of more limited occurrence. Their chemistry and pathways of biosynthesis and metabolism are well characterized. They occur in the free form as cations, but are often conjugated to small molecules like phenolic acids and also to various macromolecules. Their titer varies from approximately micromolar to more than millimolar, and depends greatly on environmental conditions, especially stress. In cereals, the activity of one of the major polyamine biosynthetic enzymes, arginine decarboxylase, is rapidly and dramatically increased by almost every studied external stress, leading to 50-fold or greater increases in putrescine titer within a few hours. The physiological significance of this increase is not yet clear, although most recent work suggests an adaptive, protective role. Polyamines produced through the action of ornithine decarboxylase, by contrast, seem essential for DNA replication and cell division. The application of exogenous polyamines produces effects on patterns of senescence and morphogenesis, suggesting but not proving a regulatory role for polyamines in these processes. The evidence for such a regulatory role is growing.
Polyamines and Their Metabolites as Diagnostic Markers of Human Diseases
Park, Myung Hee; Igarashi, Kazuei
2013-01-01
Polyamines, putrescine, spermidine and spermine, are ubiquitous in living cells and are essential for eukaryotic cell growth. These polycations interact with negatively charged molecules such as DNA, RNA, acidic proteins and phospholipids and modulate various cellular functions including macromolecular synthesis. Dysregulation of the polyamine pathway leads to pathological conditions including cancer, inflammation, stroke, renal failure and diabetes. Increase in polyamines and polyamine synthesis enzymes is often associated with tumor growth, and urinary and plasma contents of polyamines and their metabolites have been investigated as diagnostic markers for cancers. Of these, diacetylated derivatives of spermidine and spermine are elevated in the urine of cancer patients and present potential markers for early detection. Enhanced catabolism of cellular polyamines by polyamine oxidases (PAO), spermine oxidase (SMO) or acetylpolyamine oxidase (AcPAO), increases cellular oxidative stress and generates hydrogen peroxide and a reactive toxic metabolite, acrolein, which covalently incorporates into lysine residues of cellular proteins. Levels of protein-conjuagated acrolein (PC-Acro) and polyamine oxidizing enzymes were increased in the locus of brain infarction and in plasma in a mouse model of stroke and also in the plasma of stroke patients. When the combined measurements of PC-Acro, interleukin 6 (IL-6), and C-reactive protein (CRP) were evaluated, even silent brain infarction (SBI) was detected with high sensitivity and specificity. Considering that there are no reliable biochemical markers for early stage of stroke, PC-Acro and PAOs present promising markers. Thus the polyamine metabolites in plasma or urine provide useful tools in early diagnosis of cancer and stroke. PMID:24009852
Agostinelli, Enzo; Vianello, Fabio; Magliulo, Giuseppe; Thomas, Thresia; Thomas, T J
2015-01-01
Nanotechnology for cancer gene therapy is an emerging field. Nucleic acids, polyamine analogues and cytotoxic products of polyamine oxidation, generated in situ by an enzyme-catalyzed reaction, can be developed for nanotechnology-based cancer therapeutics with reduced systemic toxicity and improved therapeutic efficacy. Nucleic acid-based gene therapy approaches depend on the compaction of DNA/RNA to nanoparticles and polyamine analogues are excellent agents for the condensation of nucleic acids to nanoparticles. Polyamines and amine oxidases are found in higher levels in tumours compared to that of normal tissues. Therefore, the metabolism of polyamines spermidine and spermine, and their diamine precursor, putrescine, can be targets for antineoplastic therapy since these naturally occurring alkylamines are essential for normal mammalian cell growth. Intracellular polyamine concentrations are maintained at a cell type-specific set point through the coordinated and highly regulated interplay between biosynthesis, transport, and catabolism. In particular, polyamine catabolism involves copper-containing amine oxidases. Several studies showed an important role of these enzymes in developmental and disease-related processes in animals through the control of polyamine homeostasis in response to normal cellular signals, drug treatment, and environmental and/or cellular stress. The production of toxic aldehydes and reactive oxygen species (ROS), H2O2 in particular, by these oxidases suggests a mechanism by which amine oxidases can be exploited as antineoplastic drug targets. The combination of bovine serum amine oxidase (BSAO) and polyamines prevents tumour growth, particularly well if the enzyme has been conjugated with a biocompatible hydrogel polymer. The findings described herein suggest that enzymatically formed cytotoxic agents activate stress signal transduction pathways, leading to apoptotic cell death. Consequently, superparamagnetic nanoparticles or other advanced nanosystem based on directed nucleic acid assemblies, polyamine-induced DNA condensation, and bovine serum amine oxidase may be proposed for futuristic anticancer therapy utilizing nucleic acids, polyamines and BSAO. BSAO based nanoparticles can be employed for the generation of cytotoxic polyamine metabolites.
Polyamines in the Context of Metabolic Networks.
Wuddineh, Wegi; Minocha, Rakesh; Minocha, Subhash C
2018-01-01
Polyamines (PAs) are essential biomolecules that are known to be involved in the regulation of many plant developmental and growth processes as well as their response to different environmental stimuli. Maintaining the cellular pools of PAs or their metabolic precursors and by-products is critical to accomplish their normal functions. Therefore, the titre of PAs in the cells must be under tight regulation to enable cellular PA homeostasis. Polyamine homeostasis is hence achieved by the regulation of their input into the cellular PA pool, their conversion into secondary metabolites, their transport to other issues/organs, and their catabolism or turnover. The major contributors of input to the PA pools are their in vivo biosynthesis, interconversion between different PAs, and transport from other tissues/organs; while the output or turnover of PAs is facilitated by transport, conjugation and catabolism. Polyamine metabolic pathways including the biosynthesis, catabolism/turnover and conjugation with various organic molecules have been widely studied in all kingdoms. Discoveries on the molecular transporters facilitating the intracellular and intercellular translocation of PAs have also been reported. Numerous recent studies using transgenic approaches and mutagenesis have shown that plants can tolerate quite large concentrations of PAs in the cells; even though, at times, high cellular accumulation of PAs is quite detrimental, and so is high rate of catabolism. The mechanism by which plants tolerate such large quantities of PAs is still unclear. Interestingly, enhanced PA biosynthesis via manipulation of the PA metabolic networks has been suggested to contribute directly to increased growth and improvements in plant abiotic and biotic stress responses; hence greater biomass and productivity. Genetic manipulation of the PA metabolic networks has also been shown to improve plant nitrogen assimilation capacity, which may in turn lead to enhanced carbon assimilation. These potential benefits on top of the widely accepted role of PAs in improving plants' tolerance to biotic and abiotic stressors are invaluable tools for future plant improvement strategies.
Sridev Mohapatra; Rakesh Minocha; Stephanie Long; Subhash C. Minocha
2010-01-01
The polyamine metabolic pathway is intricately connected to metabolism of several amino acids. While ornithine and arginine are direct precursors of putrescine, they themselves are synthesized from glutamate in multiple steps involving several enzymes. Additionally, glutamate is an amino group donor for several other amino acids and acts as a substrate for biosynthesis...
Erwin, B G; Pegg, A E
1986-01-01
Exposure of rat L6 cells in culture to exogenous polyamines led to a very large increase in the activity of spermidine/spermine N1-acetyltransferase. Spermine was more potent than spermidine in bringing about this increase, but in both cases the elevated acetyltransferase activity increased the cellular conversion of spermidine into putrescine. The N1-acetyltransferase turned over very rapidly in the L6 cells, with a half-life of 9 min after spermidine and 18 min after spermine. A wide variety of synthetic polyamine analogues also brought about a substantial induction of spermidine/spermine N1-acetyltransferase activity. These included sym-norspermidine, sym-norspermine, sym-homospermidine, N4-substituted spermidine derivatives, 1,3,6-triaminohexane, 1,4,7-triaminoheptane and deoxyspergualin, which were comparable with spermidine in their potency, and N1N8-bis(ethyl)spermidine, N1N9-bis(ethyl)homospermidine, methylglyoxal bis(guanylhydrazone), ethylglyoxal bis(guanylhydrazone) and 1,1'-[(methylethanediylidene)dinitrilo]bis(3-amino-guanidine ), which were even more active than spermidine. It is suggested that these polyamine analogues may bring about a decrease in cellular polyamines not only by inhibiting biosynthesis but by stimulating the degradation of spermidine into putrescine. PMID:3800951
Hajirezaei, Mohammad R.
2016-01-01
The Yang or Met Cycle is a series of reactions catalyzing the recycling of the sulfur (S) compound 5′-methylthioadenosine (MTA) to Met. MTA is produced as a by-product in ethylene, nicotianamine, and polyamine biosynthesis. Whether the Met Cycle preferentially fuels one of these pathways in a S-dependent manner remained unclear so far. We analyzed Arabidopsis (Arabidopsis thaliana) mutants with defects in the Met Cycle enzymes 5-METHYLTHIORIBOSE-1-PHOSPHATE-ISOMERASE1 (MTI1) and DEHYDRATASE-ENOLASE-PHOSPHATASE-COMPLEX1 (DEP1) under different S conditions and assayed the contribution of the Met Cycle to the regeneration of S for these pathways. Neither mti1 nor dep1 mutants could recycle MTA but showed S-dependent reproductive failure, which was accompanied by reduced levels of the polyamines putrescine, spermidine, and spermine in mutant inflorescences. Complementation experiments with external application of these three polyamines showed that only the triamine spermine could specifically rescue the S-dependent reproductive defects of the mutant plants. Furthermore, expressing gene-reporter fusions in Arabidopsis showed that MTI1 and DEP1 were mainly expressed in the vasculature of all plant parts. Phloem-specific reconstitution of Met Cycle activity in mti1 and dep1 mutant plants was sufficient to rescue their S-dependent mutant phenotypes. We conclude from these analyses that phloem-specific S recycling during periods of S starvation is essential for the biosynthesis of polyamines required for flowering and seed development. PMID:26662272
Ketteler, M; Westenfeld, R; Gawlik, A; de Heer, E; Distler, A
2000-01-01
Pathways of L-arginine metabolism including nitric oxide, agmatine and polyamine synthesis are upregulated during glomerular inflammation in experimental glomerulonephritis. In anti-Thy-1-glomerulonephritis L-arginine-deficient diets ameliorate the disease course in this model. However, it is unclear which metabolic pathway is affected by this substrate depletion. Since polyamines are important proproliferative molecules, we studied the effect of specific polyamine synthesis blockade in vivo on mesangial cell proliferation and glomerular fibrosis in this model. Anti-Thy-1-glomerulonephritis was induced in male Sprague-Dawley rats by single-bolus injection of monoclonal ER4-antibodies. Rats were treated with difluoromethylornithine (0.5-2% in the drinking water), a selective inhibitor of the rate-limiting enzyme of polyamine synthesis, ornithine decarboxylase (ODC). Mesangial cell proliferation and matrix expansion were evaluated in PAS-stained kidney tissues. Glomerular TGF-beta and biglycan-mRNA-expression were determined by Northern blot analysis and albuminuria was measured using a competitive ELISA. Data were compared to untreated controls. Though complete inhibition of ODC activity was achieved at any time point, difluoromethlornithine treatment had no significant effect on albuminuria, glomerular matrix protein expression and mesangial cell count in this model. The acute upregulation of glomerular ODC activity above baseline in anti-Thy1-glomerulonephritis is not pathophysiologically important for disease development however, biological effects of available polyamine pools cannot be excluded by our study.
Orlovskiĭ, A A
2007-01-01
Effect of the inhibitors of polyamines biosynthesis on completely or partially hormone-dependant breast tumors (mouse Ca755 carcinoma and Walker W-256 carcinosarcoma) is essentially special: in contrary to hormone-dependant tumors, this effect may be not only breaking but stimulating as well. Change-over from one to another mode of reaction is conditioned, most probable, by hormonal status, which is determined by one or another estral cycle phase. Biochemical mechanisms of this change-over are closely connected with polyamines metabolism, namely the degree of polyamines (especially spermine) interconvertion and physiological reactivity level of the system controlling expression of ornithin-decarboxilase. At that, the first of these pathways is predominant for completely hormone-dependant Ca755 and the second one -for partially hormone-dependant W-256.
The role of polyamine catabolism in anti-tumour drug response.
Casero, R A; Wang, Y; Stewart, T M; Devereux, W; Hacker, A; Wang, Y; Smith, R; Woster, P M
2003-04-01
Interest in polyamine catabolism has increased since it has been directly associated with the cytotoxic response of multiple tumour types to exposure to specific anti-tumour polyamine analogues. Human polyamine catabolism was considered to be a two-step pathway regulated by the rate-limiting enzyme spermidine/spermine N(1)-acetyltransferase (SSAT) that provides substrate for an acetylpolyamine oxidase (APAO). Further, the super-induction of SSAT by several anti-tumour polyamine analogues has been implicated in the cytotoxic response of specific solid-tumour phenotypes to these agents. This high induction of SSAT has been correlated with cellular response to the anti-tumour polyamine analogues in several systems and considerable progress has been made in understanding the molecular mechanisms that regulate the analogue-induced expression of SSAT. A polyamine response element has been identified and the transacting transcription factors that bind and stimulate transcription of SSAT have been cloned and characterized. The link between SSAT activity and cellular toxicity is thought to be based on the production of H(2)O(2) by the activity of the constitutive APAO that uses the SSAT-produced acetylated polyamines. The high induction of SSAT and the subsequent activity of APAO are linked to the cytotoxic response of some tumour cell types to specific polyamine analogues. However, we have recently cloned a variably spliced human polyamine oxidase (PAOh1) that is inducible by specific polyamine analogues, efficiently uses unacetylated spermine as a substrate, and also produces toxic H(2)O(2) as a product. The results of studies with PAOh1 suggest that it is an additional enzyme in polyamine catabolism that has the potential to significantly contribute to polyamine homoeostasis and drug response. Most importantly, PAOh1 is induced by specific polyamine analogues in a tumour-phenotype-specific manner in cell lines representative of the major forms of solid tumours, including lung, breast, colon and prostate. The sensitivity to these anti-tumour polyamine analogues can be significantly reduced if the tumour cells are co-treated with 250 microM of the polyamine oxidase inhibitor N (1), N (4)-bis(2,3-butadienyl)-1,4-butanediamine (MDL 72,527), suggesting that the H(2)O(2) produced by PAOh1 does in fact play a direct role in the observed cytotoxicity. These results strongly implicate PAOh1 as a new target that, in combination with SSAT, may be exploited for therapeutic advantage. The current understanding of the role and regulation of these two important polyamine catabolic enzymes are discussed.
Hydrogen Peroxide and Polyamines Act as Double Edged Swords in Plant Abiotic Stress Responses.
Gupta, Kamala; Sengupta, Atreyee; Chakraborty, Mayukh; Gupta, Bhaskar
2016-01-01
The specific genetic changes through which plants adapt to the multitude of environmental stresses are possible because of the molecular regulations in the system. These intricate regulatory mechanisms once unveiled will surely raise interesting questions. Polyamines and hydrogen peroxide have been suggested to be important signaling molecules during biotic and abiotic stresses. Hydrogen peroxide plays a versatile role from orchestrating physiological processes to stress response. It helps to achieve acclimatization and tolerance to stress by coordinating intra-cellular and systemic signaling systems. Polyamines, on the other hand, are low molecular weight polycationic aliphatic amines, which have been implicated in various stress responses. It is quite interesting to note that both hydrogen peroxide and polyamines have a fine line of inter-relation between them since the catabolic pathways of the latter releases hydrogen peroxide. In this review we have tried to illustrate the roles and their multifaceted functions of these two important signaling molecules based on current literature. This review also highlights the fact that over accumulation of hydrogen peroxide and polyamines can be detrimental for plant cells leading to toxicity and pre-mature cell death.
Wild tobacco genomes reveal the evolution of nicotine biosynthesis.
Xu, Shuqing; Brockmöller, Thomas; Navarro-Quezada, Aura; Kuhl, Heiner; Gase, Klaus; Ling, Zhihao; Zhou, Wenwu; Kreitzer, Christoph; Stanke, Mario; Tang, Haibao; Lyons, Eric; Pandey, Priyanka; Pandey, Shree P; Timmermann, Bernd; Gaquerel, Emmanuel; Baldwin, Ian T
2017-06-06
Nicotine, the signature alkaloid of Nicotiana species responsible for the addictive properties of human tobacco smoking, functions as a defensive neurotoxin against attacking herbivores. However, the evolution of the genetic features that contributed to the assembly of the nicotine biosynthetic pathway remains unknown. We sequenced and assembled genomes of two wild tobaccos, Nicotiana attenuata (2.5 Gb) and Nicotiana obtusifolia (1.5 Gb), two ecological models for investigating adaptive traits in nature. We show that after the Solanaceae whole-genome triplication event, a repertoire of rapidly expanding transposable elements (TEs) bloated these Nicotiana genomes, promoted expression divergences among duplicated genes, and contributed to the evolution of herbivory-induced signaling and defenses, including nicotine biosynthesis. The biosynthetic machinery that allows for nicotine synthesis in the roots evolved from the stepwise duplications of two ancient primary metabolic pathways: the polyamine and nicotinamide adenine dinucleotide (NAD) pathways. In contrast to the duplication of the polyamine pathway that is shared among several solanaceous genera producing polyamine-derived tropane alkaloids, we found that lineage-specific duplications within the NAD pathway and the evolution of root-specific expression of the duplicated Solanaceae-specific ethylene response factor that activates the expression of all nicotine biosynthetic genes resulted in the innovative and efficient production of nicotine in the genus Nicotiana Transcription factor binding motifs derived from TEs may have contributed to the coexpression of nicotine biosynthetic pathway genes and coordinated the metabolic flux. Together, these results provide evidence that TEs and gene duplications facilitated the emergence of a key metabolic innovation relevant to plant fitness.
Berwanger, Anja; Eyrisch, Susanne; Schuster, Inge; Helms, Volkhard; Bernhardt, Rita
2010-02-01
Modulations of protein-protein interactions are a key step in regulating protein function, especially in networks. Modulators of these interactions are supposed to be candidates for the development of novel drugs. Here, we describe the role of the small, polycationic and highly abundant natural polyamines that could efficiently bind to charged spots at protein interfaces as modulators of such protein-protein interactions. Using the mitochondrial cytochrome P45011A1 (CYP11A1) electron transfer system as a model, we have analyzed the capability of putrescine, spermidine, and spermine at physiologically relevant concentrations to affect the protein-protein interactions between adrenodoxin reductase (AdR), adrenodoxin (Adx), and CYP11A1. The actions of polyamines on the individual components, on their association/dissociation, on electron transfer, and on substrate conversion were examined. These studies revealed modulating effects of polyamines on distinct interactions and on the entire system in a complex way. Modulation via changed protein-protein interactions appeared plausible from docking experiments that suggested favourable high-affinity binding sites of polyamines (spermine>spermidine>putrescine) at the AdR-Adx interface. Our findings imply for the first time that small endogenous compounds are capable of interfering with distinct components of transient protein complexes and might control protein functions by modulating electrostatic protein-protein interactions.
Polyamine catabolism is enhanced after traumatic brain injury.
Zahedi, Kamyar; Huttinger, Francis; Morrison, Ryan; Murray-Stewart, Tracy; Casero, Robert A; Strauss, Kenneth I
2010-03-01
Polyamines spermine and spermidine are highly regulated, ubiquitous aliphatic cations that maintain DNA structure and function as immunomodulators and as antioxidants. Polyamine homeostasis is disrupted after brain injuries, with concomitant generation of toxic metabolites that may contribute to secondary injuries. To test the hypothesis of increased brain polyamine catabolism after traumatic brain injury (TBI), we determined changes in catabolic enzymes and polyamine levels in the rat brain after lateral controlled cortical impact TBI. Spermine oxidase (SMO) catalyzes the degradation of spermine to spermidine, generating H2O2 and aminoaldehydes. Spermidine/spermine-N(1)-acetyltransferase (SSAT) catalyzes acetylation of these polyamines, and both are further oxidized in a reaction that generates putrescine, H2O2, and aminoaldehydes. In a rat cortical impact model of TBI, SSAT mRNA increased subacutely (6-24 h) after TBI in ipsilateral cortex and hippocampus. SMO mRNA levels were elevated late, from 3 to 7 days post-injury. Polyamine catabolism increased as well. Spermine levels were normal at 6 h and decreased slightly at 24 h, but were normal again by 72 h post-injury. Spermidine levels also decreased slightly (6-24 h), then increased by approximately 50% at 72 h post-injury. By contrast, normally low putrescine levels increased up to sixfold (6-72 h) after TBI. Moreover, N-acetylspermidine (but not N-acetylspermine) was detectable (24-72 h) near the site of injury, consistent with increased SSAT activity. None of these changes were seen in the contralateral hemisphere. Immunohistochemical confirmation indicated that SSAT and SMO were expressed throughout the brain. SSAT-immunoreactivity (SSAT-ir) increased in both neuronal and nonneuronal (likely glial) populations ipsilateral to injury. Interestingly, bilateral increases in cortical SSAT-ir neurons occurred at 72 h post-injury, whereas hippocampal changes occurred only ipsilaterally. Prolonged increases in brain polyamine catabolism are the likely cause of loss of homeostasis in this pathway. The potential for simple therapeutic interventions (e.g., polyamine supplementation or inhibition of polyamine oxidation) is an exciting implication of these studies.
Jain, Vaibhav; Raina, Shikha; Gheware, Atish Prabhakar; Singh, Rita; Rehman, Rakhshinda; Negi, Vinny; Murray Stewart, Tracy; Mabalirajan, Ulaganathan; Mishra, Adarsh Kumar; Casero, Robert A; Agrawal, Anurag; Ghosh, Balaram
2018-05-05
Airway epithelial injury is a crucial component of acute and severe asthma pathogenesis and a promising target for treatment of refractory asthma. However, the underlying mechanism of epithelial injury remains poorly explored. Though high levels of polyamines, mainly spermine, have been found in asthma and co-morbidity, their role in airway epithelial injury and the cause of their altered levels in asthma has not been explored. We measured key polyamine metabolic enzymes in lung samples from normal and asthmatic subjects and in mice with OVA-induced allergic airway inflammation (AAI). Polyamine metabolism was modulated using pharmacologic/genetic modulators. Epithelial stress and apoptosis were measured by TSLP levels and TUNEL assay, respectively. We found loss of the polyamine catabolic enzymes spermidine/spermine-N (1)-acetyltransferase-1 (SAT1) and spermine oxidase (SMOX) predominantly in bronchial epithelial cells (BECs) of human asthmatic lung samples and mice with AAI. In naïve mice, SAT1 or SMOX knockdown led to airway hyper-responsiveness, remodeling and BEC apoptosis. Conversely, in mice with AAI, overexpression of either SAT1 or SMOX alleviated asthmatic features and reduced TSLP levels and BEC apoptosis. Similarly, while pharmacological induction of SAT1 and SMOX using the polyamine analogue bis(ethyl)norspermine (BENSPM) alleviated asthmatic features with reduced TSLP levels and BEC apoptosis, pharmacological inhibition of these enzymes using BERENIL or MDL72527, respectively, worsened them. Spermine accumulation in lungs correlated with BEC apoptosis, and spermine treatment caused apoptosis of human BEAS-2B cells in vitro. Spermine induces BEC injury. Induction of polyamine catabolism may represent a novel therapeutic approach for asthma via reversing BEC stress. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Svensson, F; Kockum, I; Persson, L
1993-07-21
The polyamines are cell constituents essential for growth and differentiation. S-Adenosylmethionine decarboxylase (AdoMetDC) catalyzes a key step in the polyamine biosynthetic pathway. Methylglyoxal bis(guanylhydrazone) (MGBG) is an anti-leukemic agent with a strong inhibitory effect against AdoMetDC. However, the lack of specificity limits the usefulness of MGBG. In the present report we have used an analog of MGBG, diethylglyoxal bis(guanylhydrazone) (DEGBG), with a much greater specificity and potency against AdoMetDC, to investigate the effects of AdoMetDC inhibition on cell proliferation and polyamine metabolism in mouse L1210 leukemia cells. DEGBG was shown to effectively inhibit AdoMetDC activity in exponentially growing L1210 cells. The inhibition of AdoMetDC was reflected in a marked decrease in the cellular concentrations of spermidine and spermine. The concentration of putrescine, on the other hand, was greatly increased. Treatment with DEGBG resulted in a compensatory increase in the synthesis of AdoMetDC demonstrating an efficient feedback control. Cells seeded in the presence of DEGBG ceased to grow after a lag period of 1-2 days, indicating that the cells contained an excess of polyamines which were sufficient for one or two cell cycles in the absence of polyamine synthesis. The present results indicate that analogs of MGBG, having a greater specificity against AdoMetDC, might be valuable for studies concerning polyamines and cell proliferation.
Cerebral polyamine metabolism: inhibition of spermidine biosynthesis by dicyclohexylamine.
Porta, R; Camardella, M; Gentile, V; De Santis, A
1984-02-01
Since a specific inhibition of cerebral spermidine (Spd) synthase activity by alicyclic amines was preliminarily observed in vitro, we examined the in vivo inhibitory effectiveness of dicyclohexylamine (DCHA) on Spd biosynthesis in 21-day-old rat brain. For this purpose a previously reported HPLC procedure (Porta et al., 1981a) was modified to analyze the cerebral levels of DCHA at the time of polyamine determinations. The intraperitoneally injected DCHA was shown to cross the blood-brain barrier easily, reaching high levels in the cerebral tissue (approximately 750 nmol/g brain) within 1 h of its administration. The effect of the drug on the polyamine metabolism resulted in a significant depletion of Spd biosynthesis from the sixth hour after the treatment and in an earlier and prolonged increase of the putrescine (Pt) steady-state levels. Conversely, the spermine (Spm) endogenous pools remained unchanged throughout the 24-h post-DCHA period. Moreover, following the intracerebral administration of [1,4-14C]Pt, significantly lower specific radioactivity (s.r.a.) values for labeled Pt and Spd were recorded in the brains of DCHA-treated animals. Conversely, after intracerebral [14C]Spd injection, the s.r.a. of newly formed [14C]Spm remained unchanged, confirming the specificity of the DCHA effect on the Spd biosynthesis.
Chiapello, M; Martino, E; Perotto, S
2015-05-01
Although adaptive metal tolerance may arise in fungal populations in polluted soils, the mechanisms underlying metal-specific tolerance are poorly understood. Comparative proteomics is a powerful tool to identify variation in protein profiles caused by changing environmental conditions, and was used to investigate protein accumulation in a metal tolerant isolate of the ericoid mycorrhizal fungus Oidiodendron maius exposed to zinc and cadmium. Two-dimensional gel electrophoresis and shotgun proteomics followed by mass spectrometry lead to the identification of common and metal-specific proteins and pathways. Proteins selectively induced by cadmium exposure were molecular chaperons of the Hsp90 family, cytoskeletal proteins and components of the translation machinery. Zinc significantly up-regulated metabolic pathways related to energy production and carbohydrates metabolism, likely mirroring zinc adaptation of this fungal isolate. Common proteins induced by the two metal ions were the antioxidant enzyme Cu/Zn superoxide dismutase and ubiquitin. In mycelia exposed to zinc and cadmium, both proteomic techniques also identified agmatinase, an enzyme involved in polyamine biosynthesis. This novel finding suggests that, like plants, polyamines may have important functions in response to abiotic environmental stress in fungi. Genetic evidence also suggests that the biosynthesis of polyamines via an alternative metabolic pathway may be widespread in fungi.
Kakuchi, Ryohei; Theato, Patrick
2014-03-01
A Mitsunobu reaction of trifluoroacetamide (TFA amide) and alcohols is used in a postpolymerization modification process. The reaction is conducted on polystyrene (PSt) bearing 20 mol% TFA amide groups with 4-methyl benzyl alcohol in the presence of a N,N,N′,N ′-tetramethylazodicarboxamide and tributylphosphine as mediators. The Mitsunobu reaction on polymer proceeds efficiently, as confirmed by the obvious precipitation generation during the reaction and the conversion of TFA amide moiety reached 88.6% confirmed by 19 F NMR measurement, yielding PSt bearing tertiary TFA amide moieties. The obtained polymers featuring tertiary TFA amide moieties are deprotected in the presence of tetrabutylammonium hydroxide as a base to afford corresponding polymers featuring functionalized polyamine scaffolds with 92.5% conversion. In addition, the precise structural assignment is proven by synthesis and analysis of the model monomeric compounds and the respective model polymers.
Induction of autophagy by spermidine promotes longevity.
Eisenberg, Tobias; Knauer, Heide; Schauer, Alexandra; Büttner, Sabrina; Ruckenstuhl, Christoph; Carmona-Gutierrez, Didac; Ring, Julia; Schroeder, Sabrina; Magnes, Christoph; Antonacci, Lucia; Fussi, Heike; Deszcz, Luiza; Hartl, Regina; Schraml, Elisabeth; Criollo, Alfredo; Megalou, Evgenia; Weiskopf, Daniela; Laun, Peter; Heeren, Gino; Breitenbach, Michael; Grubeck-Loebenstein, Beatrix; Herker, Eva; Fahrenkrog, Birthe; Fröhlich, Kai-Uwe; Sinner, Frank; Tavernarakis, Nektarios; Minois, Nadege; Kroemer, Guido; Madeo, Frank
2009-11-01
Ageing results from complex genetically and epigenetically programmed processes that are elicited in part by noxious or stressful events that cause programmed cell death. Here, we report that administration of spermidine, a natural polyamine whose intracellular concentration declines during human ageing, markedly extended the lifespan of yeast, flies and worms, and human immune cells. In addition, spermidine administration potently inhibited oxidative stress in ageing mice. In ageing yeast, spermidine treatment triggered epigenetic deacetylation of histone H3 through inhibition of histone acetyltransferases (HAT), suppressing oxidative stress and necrosis. Conversely, depletion of endogenous polyamines led to hyperacetylation, generation of reactive oxygen species, early necrotic death and decreased lifespan. The altered acetylation status of the chromatin led to significant upregulation of various autophagy-related transcripts, triggering autophagy in yeast, flies, worms and human cells. Finally, we found that enhanced autophagy is crucial for polyamine-induced suppression of necrosis and enhanced longevity.
Increased polyamines as protective disease modifiers in congenital muscular dystrophy.
Kemaladewi, D U; Benjamin, J S; Hyatt, E; Ivakine, E A; Cohn, R D
2018-06-01
Most Mendelian disorders, including neuromuscular disorders, display extensive clinical heterogeneity that cannot be solely explained by primary genetic mutations. This phenotypic variability is largely attributed to the presence of disease modifiers, which can exacerbate or lessen the severity and progression of the disease. LAMA2-deficient congenital muscular dystrophy (LAMA2-CMD) is a fatal degenerative muscle disease resulting from mutations in the LAMA2 gene encoding Laminin-α2. Progressive muscle weakness is predominantly observed in the lower limbs in LAMA2-CMD patients, whereas upper limbs muscles are significantly less affected. However, very little is known about the molecular mechanism underlying differential pathophysiology between specific muscle groups. Here, we demonstrate that the triceps muscles of the dy2j/dy2j mouse model of LAMA2-CMD demonstrate very mild myopathic findings compared with the tibialis anterior (TA) muscles that undergo severe atrophy and fibrosis, suggesting a protective mechanism in the upper limbs of these mice. Comparative gene expression analysis reveals that S-Adenosylmethionine decarboxylase (Amd1) and Spermine oxidase (Smox), two components of polyamine pathway metabolism, are downregulated in the TA but not in the triceps of dy2j/dy2j mice. As a consequence, the level of polyamine metabolites is significantly lower in the TA than triceps. Normalization of either Amd1 or Smox expression in dy2j/dy2j TA ameliorates muscle fibrosis, reduces overactive profibrotic TGF-β pathway and leads to improved locomotion. In summary, we demonstrate that a deregulated polyamine metabolism is a characteristic feature of severely affected lower limb muscles in LAMA2-CMD. Targeted modulation of this pathway represents a novel therapeutic avenue for this devastating disease.
WANG, QING; WANG, YAN-LIN; WANG, KAI; YANG, JIAN-LIN; CAO, CHUN-YU
2015-01-01
The aim of the present study was to investigate the effects of the novel polyamine analog tetrabutyl propanediamine (TBP) on the growth of K562 chronic myelogenous leukemia (CML) cells and the underlying mechanism of these effects. MTT was used for the analysis of cell proliferation and flow cytometry was performed to analyze cell cycle distribution. DNA fragmentation analysis and Annexin V/propidium iodide double staining were used to identify apoptotic cells. The activity of the key enzymes in polyamine catabolism was detected using chemiluminescence. TBP can induce apoptosis and significantly inhibit K562 cell proliferation in a time- and dose-dependent manner. TBP treatment significantly induced the enzyme activity of spermine oxidase and acetylpolyamine oxidase in K562 cells, and also enhanced the inhibitory effect of the antitumor drug doxorubicin on K562 cell proliferation. As a novel polyamine analog, TBP significantly inhibited proliferation and induced apoptosis in K562 cells by upregulating the activity of the key enzymes in the polyamine catabolic pathways. TBP also increased the sensitivity of the K562 cells to the antitumor drug doxorubicin. These data indicate an important potential value of TBP for clinical therapy of human CML. PMID:25435975
Tavladoraki, Paraskevi; Cervelli, Manuela; Antonangeli, Fabrizio; Minervini, Giovanni; Stano, Pasquale; Federico, Rodolfo; Mariottini, Paolo; Polticelli, Fabio
2011-04-01
Spermine oxidase (SMO) and acetylpolyamine oxidase (APAO) are FAD-dependent enzymes that are involved in the highly regulated pathways of polyamine biosynthesis and degradation. Polyamine content is strictly related to cell growth, and dysfunctions in polyamine metabolism have been linked with cancer. Specific inhibitors of SMO and APAO would allow analyzing the precise role of these enzymes in polyamine metabolism and related pathologies. However, none of the available polyamine oxidase inhibitors displays the desired characteristics of selective affinity and specificity. In addition, repeated efforts to obtain structural details at the atomic level on these two enzymes have all failed. In the present study, in an effort to better understand structure-function relationships, SMO enzyme-substrate complex has been probed through a combination of molecular modeling, site-directed mutagenesis and biochemical studies. Results obtained indicate that SMO binds spermine in a similar conformation as that observed in the yeast polyamine oxidase FMS1-spermine complex and demonstrate a major role for residues His82 and Lys367 in substrate binding and catalysis. In addition, the SMO enzyme-substrate complex highlights the presence of an active site pocket with highly polar characteristics, which may explain the different substrate specificity of SMO with respect to APAO and provide the basis for the design of specific inhibitors for SMO and APAO.
Polyamine Catabolism Is Enhanced after Traumatic Brain Injury
Zahedi, Kamyar; Huttinger, Francis; Morrison, Ryan; Murray-Stewart, Tracy; Casero, Robert A.
2010-01-01
Abstract Polyamines spermine and spermidine are highly regulated, ubiquitous aliphatic cations that maintain DNA structure and function as immunomodulators and as antioxidants. Polyamine homeostasis is disrupted after brain injuries, with concomitant generation of toxic metabolites that may contribute to secondary injuries. To test the hypothesis of increased brain polyamine catabolism after traumatic brain injury (TBI), we determined changes in catabolic enzymes and polyamine levels in the rat brain after lateral controlled cortical impact TBI. Spermine oxidase (SMO) catalyzes the degradation of spermine to spermidine, generating H2O2 and aminoaldehydes. Spermidine/spermine-N1-acetyltransferase (SSAT) catalyzes acetylation of these polyamines, and both are further oxidized in a reaction that generates putrescine, H2O2, and aminoaldehydes. In a rat cortical impact model of TBI, SSAT mRNA increased subacutely (6–24 h) after TBI in ipsilateral cortex and hippocampus. SMO mRNA levels were elevated late, from 3 to 7 days post-injury. Polyamine catabolism increased as well. Spermine levels were normal at 6 h and decreased slightly at 24 h, but were normal again by 72 h post-injury. Spermidine levels also decreased slightly (6–24 h), then increased by ∼50% at 72 h post-injury. By contrast, normally low putrescine levels increased up to sixfold (6–72 h) after TBI. Moreover, N-acetylspermidine (but not N-acetylspermine) was detectable (24–72 h) near the site of injury, consistent with increased SSAT activity. None of these changes were seen in the contralateral hemisphere. Immunohistochemical confirmation indicated that SSAT and SMO were expressed throughout the brain. SSAT-immunoreactivity (SSAT-ir) increased in both neuronal and nonneuronal (likely glial) populations ipsilateral to injury. Interestingly, bilateral increases in cortical SSAT-ir neurons occurred at 72 h post-injury, whereas hippocampal changes occurred only ipsilaterally. Prolonged increases in brain polyamine catabolism are the likely cause of loss of homeostasis in this pathway. The potential for simple therapeutic interventions (e.g., polyamine supplementation or inhibition of polyamine oxidation) is an exciting implication of these studies. PMID:19968558
Deciphering the Translation Initiation Factor 5A Modification Pathway in Halophilic Archaea
Graf, Michael; Blaby, Ian K.; Makkay, Andrea M.; Starosta, Agata L.; Papke, R. Thane; Oshima, Tairo; Wilson, Daniel N.
2016-01-01
Translation initiation factor 5A (IF5A) is essential and highly conserved in Eukarya (eIF5A) and Archaea (aIF5A). The activity of IF5A requires hypusine, a posttranslational modification synthesized in Eukarya from the polyamine precursor spermidine. Intracellular polyamine analyses revealed that agmatine and cadaverine were the main polyamines produced in Haloferax volcanii in minimal medium, raising the question of how hypusine is synthesized in this halophilic Archaea. Metabolic reconstruction led to a tentative picture of polyamine metabolism and aIF5A modification in Hfx. volcanii that was experimentally tested. Analysis of aIF5A from Hfx. volcanii by LC-MS/MS revealed it was exclusively deoxyhypusinylated. Genetic studies confirmed the role of the predicted arginine decarboxylase gene (HVO_1958) in agmatine synthesis. The agmatinase-like gene (HVO_2299) was found to be essential, consistent with a role in aIF5A modification predicted by physical clustering evidence. Recombinant deoxyhypusine synthase (DHS) from S. cerevisiae was shown to transfer 4-aminobutyl moiety from spermidine to aIF5A from Hfx. volcanii in vitro. However, at least under conditions tested, this transfer was not observed with the Hfx. volcanii DHS. Furthermore, the growth of Hfx. volcanii was not inhibited by the classical DHS inhibitor GC7. We propose a model of deoxyhypusine synthesis in Hfx. volcanii that differs from the canonical eukaryotic pathway, paving the way for further studies. PMID:28053595
Gil-Amado, Jose A; Gomez-Jimenez, Maria C
2012-06-01
Exogenous ethylene and some inhibitors of polyamine biosynthesis can induce mature-fruit abscission in olive, which could be associated with decreased nitric oxide production as a signaling molecule. Whether H₂O₂ also plays a signaling role in mature-fruit abscission is unknown. The possible involvement of H₂O₂ and polyamine in ethylene-induced mature-fruit abscission was examined in the abscission zone and adjacent cells of two olive cultivars. Endogenous H₂O₂ showed an increase in the abscission zone during mature-fruit abscission, suggesting that accumulated H₂O₂ may participate in abscission signaling. On the other hand, we followed the expression of two genes involved in the polyamine biosynthesis pathway during mature-fruit abscission and in response to ethylene or inhibitors of ethylene and polyamine. OeSAMDC1 and OeSPDS1 were expressed differentially within and between the abscission zones of the two cultivars. OeSAMDC1 showed slightly lower expression in association with mature-fruit abscission. Furthermore, our data show that exogenous ethylene or inhibitors of polyamine encourage the free putrescine pool and decrease the soluble-conjugated spermidine, spermine, homospermidine, and cadaverine in the olive abscission zone, while ethylene inhibition by CoCl₂ increases these soluble conjugates, but does not affect free putrescine. Although the impact of these treatments on polyamine metabolism depends on the cultivar, the results confirm that the mature-fruit abscission may be accompanied by an inhibition of S-adenosyl methionine decarboxylase activity, and the promotion of putrescine synthesis in olive abscission zone, suggesting that endogenous putrescine may play a complementary role to ethylene in the normal course of mature-fruit abscission.
Mitoguazone induces apoptosis via a p53-independent mechanism.
Davidson, K; Petit, T; Izbicka, E; Koester, S; Von Hoff, D D
1998-08-01
Mitoguazone (methylglyoxal bisguanylhydrazone, methyl-GAG or MGBG) is a synthetic polycarbonyl derivative with activity in patients with Hodgkin's and non-Hodgkin's lymphoma, head and neck cancer, prostate cancer, and esophageal cancer. Mitoguazone has also recently been documented to have activity in patients with AIDS-related lymphoma. Among anticancer drugs, mitoguazone has a unique mechanism of action via interference with the polyamine biosynthetic pathway. Polyamines stabilize DNA structure by non-covalent cross-bridging between phosphate groups on opposite strands. In addition, mitoguazone causes uncoupling of oxidative phosphorylation. In this study, the ability of mitoguazone to induce apoptosis by inhibiting the polyamine pathway was assessed in three Burkitt's lymphoma cell lines (Raji, Ramos and Daudi) and one prostate carcinoma cell line (MPC 3). Additional evaluations were performed in two human breast cancer cell lines (MCF7 with wild-type p53 and VM4K with mutated p53) to determine whether the p53 tumor suppressor gene was required for efficient apoptosis induction. The present study demonstrated that mitoguazone induces apoptosis in all the different human cancer cell lines tested in a concentration- and time-dependent way, and triggers a p53-independent programmed cell death in the human breast cancer MCF7 cell line.
Plasticizing Effects of Polyamines in Protein-Based Films
Sabbah, Mohammed; Di Pierro, Prospero; Giosafatto, C. Valeria L.; Esposito, Marilena; Mariniello, Loredana; Regalado-Gonzales, Carlos; Porta, Raffaele
2017-01-01
Zeta potential and nanoparticle size were determined on film forming solutions of native and heat-denatured proteins of bitter vetch as a function of pH and of different concentrations of the polyamines spermidine and spermine, both in the absence and presence of the plasticizer glycerol. Our results showed that both polyamines decreased the negative zeta potential of all samples under pH 8.0 as a consequence of their ionic interaction with proteins. At the same time, they enhanced the dimension of nanoparticles under pH 8.0 as a result of macromolecular aggregations. By using native protein solutions, handleable films were obtained only from samples containing either a minimum of 33 mM glycerol or 4 mM spermidine, or both compounds together at lower glycerol concentrations. However, 2 mM spermidine was sufficient to obtain handleable film by using heat-treated samples without glycerol. Conversely, brittle materials were obtained by spermine alone, thus indicating that only spermidine was able to act as an ionic plasticizer. Lastly, both polyamines, mainly spermine, were found able to act as “glycerol-like” plasticizers at concentrations higher than 5 mM under experimental conditions at which their amino groups are undissociated. Our findings open new perspectives in obtaining protein-based films by using aliphatic polycations as components. PMID:28489025
A mass spectrometric method to determine activities of enzymes involved in polyamine catabolism.
Moriya, Shunsuke; Iwasaki, Kaori; Samejima, Keijiro; Takao, Koichi; Kohda, Kohfuku; Hiramatsu, Kyoko; Kawakita, Masao
2012-10-20
An analytical method for the determination of three polyamines (putrescine, spermidine, and spermine) and five acetylpolyamines [N(1)-acetylspermidine (N(1)AcSpd), N(8)-acetylspermidine (N(8)AcSpd), N(1)-acetylspermine, N(1),N(8)-diacetylspermidine, and N(1),N(12)-diacetylspermine] involved in the polyamine catabolic pathway has been developed using a hybrid tandem mass spectrometer. Heptafluorobutyryl (HFB) derivatives of these compounds and respective internal standards labeled with stable isotopes were analyzed simultaneously by TOF MS, based on peak areas appearing at appropriate m/z values. The isomers, N(1)AcSpd and N(8)AcSpd were determined from their fragment ions, the acetylamidopropyl and acetylamidobutyl groups, respectively, using MS/MS with (13)C(2)-N(1)AcSpd and (13)C(2)-N(8)AcSpd which have the (13)C(2)-acetyl group as an internal standard. The TOF MS method was successfully applied to measure the activity of enzymes involved in polyamine catabolic pathways, namely N(1)-acetylpolyamine oxidase (APAO), spermine oxidase (SMO), and spermidine/spermine N(1)-acetyltransferase (SSAT). The following natural substrates and products labeled with stable isotopes considering the application to biological samples were identified; for APAO, [4,9,12-(15)N(3)]-N(1)-acetylspermine and [1,4,8-(15)N(3)]spermidine ((15)N(3)-Spd), respectively; for SMO, [1,4,8,12-(15)N(4)]spermine and (15)N(3)-Spd, respectively; and for SSAT, (15)N(3)-Spd and [1,4,8-(15)N(3)]-N(1)-acetylspermidine, respectively. Copyright © 2012 Elsevier B.V. All rights reserved.
Polyamines and Hypusination Are Required for Ebolavirus Gene Expression and Replication
Olsen, Michelle E.; Filone, Claire Marie; Rozelle, Dan; Mire, Chad E.; Agans, Krystle N.; Hensley, Lisa
2016-01-01
ABSTRACT Ebolavirus (EBOV) is an RNA virus that is known to cause severe hemorrhagic fever in humans and other primates. EBOV successfully enters and replicates in many cell types. This replication is dependent on the virus successfully coopting a number of cellular factors. Many of these factors are currently unidentified but represent potential targets for antiviral therapeutics. Here we show that cellular polyamines are critical for EBOV replication. We found that small-molecule inhibitors of polyamine synthesis block gene expression driven by the viral RNA-dependent RNA polymerase. Short hairpin RNA (shRNA) knockdown of the polyamine pathway enzyme spermidine synthase also resulted in reduced EBOV replication. These findings led us to further investigate spermidine, a polyamine that is essential for the hypusination of eukaryotic initiation factor 5A (eIF5A). Blocking the hypusination of eIF5A (and thereby inhibiting its function) inhibited both EBOV gene expression and viral replication. The mechanism appears to be due to the importance of hypusinated eIF5A for the accumulation of VP30, an essential component of the viral polymerase. The same reduction in hypusinated eIF5A did not alter the accumulation of other viral polymerase components. This action makes eIF5A function an important gate for proper EBOV polymerase assembly and function through the control of a single virus protein. PMID:27460797
Marcora, M Silvina; Cejas, Silvina; González, Nélida S; Carrillo, Carolina; Algranati, Israel D
2010-10-01
The metabolism of polyamines as well as their functions as growth regulators in plants have been extensively studied for many years. However, almost nothing is known about the biosynthesis and roles of these substances in Phytomonas spp., parasites of several plants. We have used HPLC and electrophoretic analyses to investigate the presence and metabolism of polyamines in Phytomonas Jma strain, detecting both putrescine and spermidine but not spermine. Experiments carried out by incubation of intact parasites with labelled ornithine or putrescine showed the formation of radioactive putrescine or spermidine, respectively. These results indicated that Phytomonas Jma can synthesise these polyamines through the action of ornithine decarboxylase (ODC) and spermidine synthase. On the other hand, we could not detect the conversion of arginine to agmatine, suggesting the absence of arginine decarboxylase (ADC) in Phytomonas. However, we cannot ensure the complete absence of this enzymatic activity in the parasite. Phytomonas ODC required pyridoxal 5'-phosphate for maximum activity and was specifically inhibited by α-difluoromethylornithine. The metabolic turnover of the enzyme was very high, with a half-life of 10-15 min, one of the shortest found among all ODC enzymes studied to date. The parasite proteasome seems to be involved in degradation of the enzyme, since Phytomonas ODC can be markedly stabilized by MG-132, a well known proteasome inhibitor. The addition of polyamines to Phytomonas cultures did not decrease ODC activity, strongly suggesting the possible absence of antizyme in this parasite. Copyright © 2010 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
Long-Distance Transport of Thiamine (Vitamin B1) Is Concomitant with That of Polyamines1[OPEN
Martinis, Jacopo; Gas-Pascual, Elisabet; Szydlowski, Nicolas; Crèvecoeur, Michèle; Gisler, Alexandra; Bürkle, Lukas; Fitzpatrick, Teresa B.
2016-01-01
Thiamine (vitamin B1) is ubiquitous and essential for cell energy supply in all organisms as a vital metabolic cofactor, known for over a century. In plants, it is established that biosynthesis de novo is taking place predominantly in green tissues and is furthermore limited to plastids. Therefore, transport mechanisms are required to mediate the movement of this polar metabolite from source to sink tissue to activate key enzymes in cellular energy generating pathways but are currently unknown. Similar to thiamine, polyamines are an essential set of charged molecules required for diverse aspects of growth and development, the homeostasis of which necessitates long-distance transport processes that have remained elusive. Here, a yeast-based screen allowed us to identify Arabidopsis (Arabidopsis thaliana) PUT3 as a thiamine transporter. A combination of biochemical, physiological, and genetic approaches permitted us to show that PUT3 mediates phloem transport of both thiamine and polyamines. Loss of function of PUT3 demonstrated that the tissue distribution of these metabolites is altered with growth and developmental consequences. The pivotal role of PUT3 mediated thiamine and polyamine homeostasis in plants, and its importance for plant fitness is revealed through these findings. PMID:27006489
Zhu, Qingsong; Jin, Lihua; Casero, Robert A.
2013-01-01
Our previous studies demonstrated that specific polyamine analogues, oligoamines, down-regulated the activity of a key polyamine biosynthesis enzyme, ornithine decarboxylase (ODC), and suppressed expression of estrogen receptor alpha (ERα) in human breast cancer cells. However, the mechanism underlying the potential regulation of ERα expression by polyamine metabolism has not been explored. Here, we demonstrated that RNAi-mediated knockdown of ODC (ODC KD) down-regulated the polyamine pool, and hindered growth in ERα-positive MCF7 and T47D and ERα-negative MDA-MB-231 breast cancer cells. ODC KD significantly induced the expression and activity of the key polyamine catabolism enzymes, spermine oxidase (SMO) and spermidine/spermine N1-acetyltransferase (SSAT). However, ODC KD-induced growth inhibition could not be reversed by exogenous spermidine or overexpression of antizyme inhibitor (AZI), suggesting that regulation of ODC on cell proliferation may involve the signaling pathways independent of polyamine metabolism. In MCF7 and T47D cells, ODC KD, but not DFMO treatment, diminished the mRNA and protein expression of ERα. Overexpression of antizyme (AZ), an ODC inhibitory protein, suppressed ERα expression, suggesting that ODC plays an important role in regulation of ERα expression. Decrease of ERα expression by ODC siRNA altered the mRNA expression of a subset of ERα response genes. Our previous analysis showed that oligoamines disrupt the binding of Sp1 family members to an ERα minimal promoter element containing GC/CA-rich boxes. By using DNA affinity precipitation and mass spectrometry analysis, we identified ZBTB7A, MeCP2, PARP-1, AP2, and MAZ as co-factors of Sp1 family members that are associated with the ERα minimal promoter element. Taken together, these data provide insight into a novel antiestrogenic mechanism for polyamine biosynthesis enzymes in breast cancer. PMID:22976807
Bagga, S.; Rochford, J.; Klaene, Z.; Kuehn, G. D.; Phillips, G. C.
1997-01-01
The biosynthesis of polyamines from the diamine putrescine is not fully understood in higher plants. A putrescine aminopropyltransferase (PAPT) enzyme activity was characterized in alfalfa (Medicago sativa L.). This enzyme activity was highly specific for putrescine as the initial substrate and did not recognize another common diamine, 1,3-diaminopropane, or higher-molecular-weight polyamines such as spermidine and spermine as alternative initial substrates. The enzyme activity was inhibited by a general inhibitor of aminopropyltransferases, 5[prime]-methylthioadenosine, and by a specific inhibitor of PAPTs, cyclohexylammonium sulfate. The initial substrate specificity and inhibition characteristics of the enzyme activity suggested that it is a classical example of a PAPT. However, this enzyme activity yielded multiple polyamine products, which is uncharacteristic of PAPTs. The major reaction product of PAPT activity in alfalfa was spermidine. The next most abundant products of the enzyme reaction using putrescine as the initial substrate included the tetramines spermine and thermospermine. These two tetramines were distinguished by thin-layer chromatography to be distinct reaction products exhibiting differential rates of formation. In addition, the uncommon polyamines homocaldopentamine and homocaldohexamine were tentatively identified as minor enzymatic reaction products but only in extracts prepared from osmotic stresstolerant alfalfa cultivars. PAPT activity from alfalfa was highest in meristematic shoot tip and floral bud tissues and was not detected in older, nonmeristematic tissues. Product inhibition of the enzyme activity was observed after spermidine was added into the in vitro assay for alfalfa PAPT activity. A biosynthetic pathway is proposed that accounts for the characteristics of this PAPT activity and accommodates a novel scheme by which certain uncommon polyamines are produced in plants. PMID:12223719
NASA Technical Reports Server (NTRS)
Tiburcio, A. F.; Kaur-Sawhney, R.; Galston, A. W.
1986-01-01
We have attempted to improve the viability of cereal mesophyll protoplasts by pretreatment of leaves with DL-alpha-difluoromethylarginine (DFMA), a specific 'suicide' inhibitor of the enzyme (arginine decarboxylase) responsible for their osmotically induced putrescine accumulation. Leaf pretreatment with DFMA before a 6 hour osmotic shock caused a 45% decrease of putrescine and a 2-fold increase of spermine titer. After 136 hours of osmotic stress, putrescine titer in DFMA-pretreated leaves increased by only 50%, but spermidine and spermine titers increased dramatically by 3.2- and 6-fold, respectively. These increases in higher polyamines could account for the reduced chlorophyll loss and enhanced ability of pretreated leaves to incorporate tritiated thymidine, uridine, and leucine into macromolecules. Pretreatment with DFMA significantly improved the overall viability of the protoplasts isolated from these leaves. The results support the view that the osmotically induced rise in putrescine and blockage of its conversion to higher polyamines may contribute to the lack of sustained cell division in cereal mesophyll protoplasts, although other undefined factors must also play a major role.
Dual delivery systems based on polyamine analog BENSpm as prodrug and gene delivery vectors
NASA Astrophysics Data System (ADS)
Zhu, Yu
Combination drug and gene therapy shows promise in cancer treatment. However, the success of such strategy requires careful selection of the therapeutic agents, as well as development of efficient delivery vectors. BENSpm (N 1, N11-bisethylnorspermine), a polyamine analogue targeting the intracellular polyamine pathway, draws our special attention because of the following reasons: (1) polyamine pathway is frequently dysregulated in cancer; (2) BENSpm exhibits multiple functions to interfere with the polyamine pathway, such as to up-regulate polyamine metabolism enzymes and down-regulate polyamine biosynthesis enzymes. Therefore BENSpm depletes all natural polyamines and leads to apoptosis and cell growth inhibition in a wide range of cancers; (3) preclinical studies proved that BENSpm can act synergistically with various chemotherapy agents, making it a promising candidate in combination therapy; (4) multiple positive charges in BENSpm enable it as a suitable building block for cationic polymers, which can be further applied to gene delivery. In this dissertation, our goal was to design dual-function delivery vector based on BENSpm that can function as a gene delivery vector and, after intracellular degradation, as an active anticancer agent targeting dysregulated polyamine metabolism. We first demonstrated strong synergism between BENSpm and a potential therapeutic gene product TRAIL. Strong synergism was obtained in both estrogen-dependent MCF-7 breast cancer cells and triple-negative MDA-MB-231 breast cancer cells. Significant dose reduction of TRAIL in combination with BENSpm in MDA-MB-231 cells, together with the fact that BENSpm rendered MCF-7 cells more sensitive to TRAIL treatment verified our rationale of designing BENSpm-based delivery platform. This was expected to be beneficial for overcoming drug resistance in chemotherapy, as well as boosting the therapeutic effect of therapeutic genes. We first designed a lipid-based BENSpm dual vector (Lipo-SS-BEN) capable of intracellular release of BENSpm using thiolytically sensitive dithiobenzyl carbamate linker. Similar activity on SSAT enzyme induction by Lipo-SS-BEN compared with BENSpm free drug verified the success of this prodrug design. Biodegradability of Lipo-SS-BEN contributed to decreased toxicity compared with nondegradable control LipoBEN. However, decreased enhancement of TRAIL activity was observed for Lipo-SS-BEN when compared with BENSpm, indicating that the lipid-related toxicity diminished the synergism. In addition, compared with LipoBEN and DOTAP, decreased transfection efficiency of Lipo-SS-BEN demonstrated instability of Lipo-SS-BEN in extracellular environment. In order to design a dual delivery vector with reduced vector toxicity and improved linker stability, we employed dendritic polyglycerol (PG) as a safe carrier backbone, onto which BENSpm was conjugated through carbamate linkage (PG-BEN). Polymers with norspermine (PG-Nor) shell and amine-terminated PG (PG-NH2) were synthesized as controls. The BENSpm dual vector PG-BEN demonstrated superior gene delivery function, and showed decreased toxicity compared with the control polymers. However, compared with BENSpm, which depleted all natural polyamines, PG-BEN only down-regulated intracellular putrescine levels. In addition, no free BENSpm was detected in PG-BEN treated cells. These results suggested that in order to take full advantage of BENSpm anticancer activity, alternative linker chemistry needs to be further explored. We then incorporated bis(2-hydroxyethyl) disulfide as a self-immolative linker to synthesize polymer prodrugs of BENSpm (DSS-BEN). The proposed mechanism of BENSpm release from DSS-BEN contains two steps: disulfide bond is first cleaved in the reducing intracellular space, then the intermediate further undergoes slow intramolecular cyclization to release free BENSpm. Cell line-dependent BENSpm release after DSS-BEN treatment was observed using HPLC analysis, demonstrating the success of our linker strategy. DSS-BEN showed comparable transfection efficiency as polyethylenimine and showed decreased toxicity in several cell lines compared with the nondegradable control DCC-BEN. We further demonstrated that DSS-BEN could act synergistically with several therapeutic agents, making it a promising delivery platform for combination therapy in cancer. In all, we have successfully developed a dual delivery vector based on BENSpm, which fulfills its function as a gene delivery vector as well as a prodrug of BENSpm, and possesses synergistic potential to augment the effect of the co-delivered agents.
Fahrmann, Johannes F.; Grapov, Dmitry; Wanichthanarak, Kwanjeera; DeFelice, Brian C.; Salemi, Michelle R.; Rom, William N.; Gandara, David R.; Phinney, Brett S.; Fiehn, Oliver; Pass, Harvey
2017-01-01
Abstract Lung cancer is the leading cause of cancer mortality in the United States with non-small cell lung cancer adenocarcinoma being the most common histological type. Early perturbations in cellular metabolism are a hallmark of cancer, but the extent of these changes in early stage lung adenocarcinoma remains largely unknown. In the current study, an integrated metabolomics and proteomics approach was utilized to characterize the biochemical and molecular alterations between malignant and matched control tissue from 27 subjects diagnosed with early stage lung adenocarcinoma. Differential analysis identified 71 metabolites and 1102 proteins that delineated tumor from control tissue. Integrated results indicated four major metabolic changes in early stage adenocarcinoma (1): increased glycosylation and glutaminolysis (2); elevated Nrf2 activation (3); increase in nicotinic and nicotinamide salvaging pathways and (4) elevated polyamine biosynthesis linked to differential regulation of the s-adenosylmethionine/nicotinamide methyl-donor pathway. Genomic data from publicly available databases were included to strengthen proteomic findings. Our findings provide insight into the biochemical and molecular biological reprogramming that may accompany early stage lung tumorigenesis and highlight potential therapeutic targets. PMID:28049629
Vigeolas, Helene; Chinoy, Catherine; Zuther, Ellen; Blessington, Bernard; Geigenberger, Peter; Domoney, Claire
2008-01-01
Several legume seed proteins that are potentially allergenic, poorly digested by farm animals, and/or have undesirable functional properties, have been described. One of these is the albumin protein in pea (Pisum sativum) called PA2. A naturally occurring mutant line that lacks PA2 has been exploited in studies to determine the biological function of this nonstorage protein in seed development. The mutant, which has a small seed, a tall plant phenotype, and lacks most of the PA2-encoding genes, has been crossed with a standard cultivar, ‘Birte,’ which contains PA2 to give rise to a recombinant inbred (RI) population. An F3 line carrying the mutation and having a short plant phenotype has been used to generate backcross (BC) lines with ‘Birte.’ Despite having a lower albumin content, seeds from the mutant parent and RI lines lacking PA2 have an equivalent or higher seed nitrogen content. Metabolite profiling of seeds revealed major differences in amino acid composition and polyamine content in the two parent lines. This was investigated further in BC lines, where the effects of differences in seed size and plant height between the two parents were eliminated. Here, differences in polyamine synthesis were maintained as was a difference in total seed protein between the BC line lacking PA2 and ‘Birte.’ Analysis of enzyme activities in the pathways of polyamine synthesis revealed that the differences in spermidine content were attributable to changes in the overall activities of spermidine synthase and arginine decarboxylase. Although the genes encoding spermidine synthase and PA2 both localized to the pea linkage group I, the two loci were shown not to be closely linked and to have recombined in the BC lines. A distinct locus on linkage group III contains a gene that is related to PA2 but expressed predominantly in flowers. The results provide evidence for a role of PA2 in regulating polyamine metabolism, which has important functions in development, metabolism, and stress responses in plants. PMID:18024559
Chlorella viruses contain genes encoding a complete polyamine biosynthetic pathway
Baumann, Sascha; Sander, Adrianne; Gurnon, James R.; Yanai-Balser, Giane; VanEtten, James L.; Piotrowski, Markus
2007-01-01
Two genes encoding the putative polyamine biosynthetic enzymes agmatine iminohydrolase (AIH) and N-carbamoylputrescine amidohydrolase (CPA) were cloned from the chloroviruses PBCV-1, NY-2A and MT325. They were expressed in Escherichia coli to form C-terminal (His)6-tagged proteins and the recombinant proteins were purified by Ni2+- binding affinity chromatography. The biochemical properties of the two enzymes are similar to AIH and CPA enzymes from Arabidopsis thaliana and Pseudomonas aeruginosa. Together with the previously known virus genes encoding ornithine/arginine decarboxlyase (ODC/ADC) and homospermidine synthase, the chloroviruses have genes that encode a complete set of functional enzymes that synthesize the rare polyamine homospermidine from arginine via agmatine, N-carbamoylputrescine and putrescine. The PBCV-1 aih and cpa genes are expressed early during virus infection together with the odc/adc gene, suggesting that biosynthesis of putrescine is important in early stages of viral replication. The aih and cpa genes are widespread in the chlorella viruses. PMID:17101165
Mandal, Abhishek; Das, Sushmita; Roy, Saptarshi; Ghosh, Ayan Kumar; Sardar, Abul Hasan; Verma, Sudha; Saini, Savita; Singh, Ruby; Abhishek, Kumar; Kumar, Ajay; Mandal, Chitra; Das, Pradeep
2016-01-01
The growth and survival of intracellular parasites depends on the availability of extracellular nutrients. Deprivation of nutrients viz glucose or amino acid alters redox balance in mammalian cells as well as some lower organisms. To further understand the relationship, the mechanistic role of L-arginine in regulation of redox mediated survival of Leishmania donovani promastigotes was investigated. L-arginine deprivation from the culture medium was found to inhibit cell growth, reduce proliferation and increase L-arginine uptake. Relative expression of enzymes, involved in L-arginine metabolism, which leads to polyamine and trypanothione biosynthesis, were downregulated causing decreased production of polyamines in L-arginine deprived parasites and cell death. The resultant increase in reactive oxygen species (ROS), due to L-arginine deprivation, correlated with increased NADP+/NADPH ratio, decreased superoxide dismutase (SOD) level, increased lipid peroxidation and reduced thiol content. A deficiency of L-arginine triggered phosphatidyl serine externalization, a change in mitochondrial membrane potential, release of intracellular calcium and cytochrome-c. This finally led to DNA damage in Leishmania promastigotes. In summary, the growth and survival of Leishmania depends on the availability of extracellular L-arginine. In its absence the parasite undergoes ROS mediated, caspase-independent apoptosis-like cell death. Therefore, L-arginine metabolism pathway could be a probable target for controlling the growth of Leishmania parasites and disease pathogenesis. PMID:26808657
Smirnova, Olga A.; Bartosch, Birke; Zakirova, Natalia F.; Kochetkov, Sergey N.
2018-01-01
Reactive oxygen species (ROS) are produced in various cell compartments by an array of enzymes and processes. An excess of ROS production can be hazardous for normal cell functioning, whereas at normal levels, ROS act as vital regulators of many signal transduction pathways and transcription factors. ROS production is affected by a wide range of viruses. However, to date, the impact of viral infections has been studied only in respect to selected ROS-generating enzymes. The role of several ROS-generating and -scavenging enzymes or cellular systems in viral infections has never been addressed. In this review, we focus on the roles of biogenic polyamines and oxidative protein folding in the endoplasmic reticulum (ER) and their interplay with viruses. Polyamines act as ROS scavengers, however, their catabolism is accompanied by H2O2 production. Hydrogen peroxide is also produced during oxidative protein folding, with ER oxidoreductin 1 (Ero1) being a major source of oxidative equivalents. In addition, Ero1 controls Ca2+ efflux from the ER in response to e.g., ER stress. Here, we briefly summarize the current knowledge on the physiological roles of biogenic polyamines and the role of Ero1 at the ER, and present available data on their interplay with viral infections. PMID:29673197
Identification of aaNAT5b as a spermine N-acetyltransferase in the mosquito, Aedes aegypti.
Guan, Huai; Wang, Maoying; Liao, Chenghong; Liang, Jing; Mehere, Prajwalini; Tian, Meiling; Liu, Hairong; Robinson, Howard; Li, Jianyong; Han, Qian
2018-01-01
Mosquitoes transmit a number of diseases in animals and humans, including Dengue, Chikungunya and Zika viruses that affect millions of people each year. Controlling the disease-transmitting mosquitoes has proven to be a successful strategy to reduce the viruses transmission. Polyamines are required for the life cycle of the RNA viruses, Chikungunya virus and Zika virus, and a depletion of spermidine and spermine in the host via induction of spermine N-acetyltransferase restricts their replication. Spermine N-acetyltransferase is a key catabolic enzyme in the polyamine pathway, however there is no information of the enzyme identification in any insects. Aliphatic polyamines play a fundamental role in tissue growth and development in organisms. They are acetylated by spermidine/spermine N1-acetyltransferase (SAT). In this study we provided a molecular and biochemical identification of SAT from Aedes aegypti mosquitoes. Screening of purified recombinant proteins against polyamines established that aaNAT5b, named previously based on sequence similarity with identified aaNAT1 in insects, is active to spermine and spermidine. A crystal structure was determined and used in molecular docking in this study. Key residues were identified to be involved in spermine binding using molecular docking and simulation. In addition, SAT transcript was down regulated by blood feeding using a real time PCR test. Based on its substrate profile and transcriptional levels after blood feeding, together with previous reports for polyamines required in arboviruses replication, SAT might be potentially used as a target to control arboviruses with human interference.
Gobert, Alain P; Al-Greene, Nicole T; Singh, Kshipra; Coburn, Lori A; Sierra, Johanna C; Verriere, Thomas G; Luis, Paula B; Schneider, Claus; Asim, Mohammad; Allaman, Margaret M; Barry, Daniel P; Cleveland, John L; Destefano Shields, Christina E; Casero, Robert A; Washington, M Kay; Piazuelo, M Blanca; Wilson, Keith T
2018-01-01
Polyamines have been implicated in numerous biological processes, including inflammation and carcinogenesis. Homeostatic regulation leads to interconversion of the polyamines putrescine and the downstream metabolites spermidine and spermine. The enzyme spermine oxidase (SMOX), which back-converts spermine to spermidine, contributes to regulation of polyamine levels, but can also have other effects. We have implicated SMOX in gastric inflammation and carcinogenesis due to infection by the pathogen Helicobacter pylori . In addition, we reported that SMOX can be upregulated in humans with inflammatory bowel disease. Herein, we utilized Smox -deficient mice to examine the role of SMOX in two murine colitis models, Citrobacter rodentium infection and dextran sulfate sodium (DSS)-induced epithelial injury. In C. rodentium -infected wild-type (WT) mice, there were marked increases in colon weight/length and histologic injury, with mucosal hyperplasia and inflammatory cell infiltration; these changes were ameliorated in Smox -/- mice. In contrast, with DSS, Smox -/- mice exhibited substantial mortality, and increased body weight loss, colon weight/length, and histologic damage. In C. rodentium -infected WT mice, there were increased colonic levels of the chemokines CCL2, CCL3, CCL4, CXCL1, CXCL2, and CXCL10, and the cytokines IL-6, TNF-α, CSF3, IFN-γ, and IL-17; each were downregulated in Smox -/- mice. In DSS colitis, increased levels of IL-6, CSF3, and IL-17 were further increased in Smox -/- mice. In both models, putrescine and spermidine were increased in WT mice; in Smox -/- mice, the main effect was decreased spermidine and spermidine/spermine ratio. With C. rodentium , polyamine levels correlated with histologic injury, while with DSS, spermidine was inversely correlated with injury. Our studies indicate that SMOX has immunomodulatory effects in experimental colitis via polyamine flux. Thus, SMOX contributes to the immunopathogenesis of C. rodentium infection, but is protective in DSS colitis, indicating the divergent effects of spermidine.
Gobert, Alain P.; Al-Greene, Nicole T.; Singh, Kshipra; Coburn, Lori A.; Sierra, Johanna C.; Verriere, Thomas G.; Luis, Paula B.; Schneider, Claus; Asim, Mohammad; Allaman, Margaret M.; Barry, Daniel P.; Cleveland, John L.; Destefano Shields, Christina E.; Casero, Robert A.; Washington, M. Kay; Piazuelo, M. Blanca; Wilson, Keith T.
2018-01-01
Polyamines have been implicated in numerous biological processes, including inflammation and carcinogenesis. Homeostatic regulation leads to interconversion of the polyamines putrescine and the downstream metabolites spermidine and spermine. The enzyme spermine oxidase (SMOX), which back-converts spermine to spermidine, contributes to regulation of polyamine levels, but can also have other effects. We have implicated SMOX in gastric inflammation and carcinogenesis due to infection by the pathogen Helicobacter pylori. In addition, we reported that SMOX can be upregulated in humans with inflammatory bowel disease. Herein, we utilized Smox-deficient mice to examine the role of SMOX in two murine colitis models, Citrobacter rodentium infection and dextran sulfate sodium (DSS)-induced epithelial injury. In C. rodentium-infected wild-type (WT) mice, there were marked increases in colon weight/length and histologic injury, with mucosal hyperplasia and inflammatory cell infiltration; these changes were ameliorated in Smox−/− mice. In contrast, with DSS, Smox−/− mice exhibited substantial mortality, and increased body weight loss, colon weight/length, and histologic damage. In C. rodentium-infected WT mice, there were increased colonic levels of the chemokines CCL2, CCL3, CCL4, CXCL1, CXCL2, and CXCL10, and the cytokines IL-6, TNF-α, CSF3, IFN-γ, and IL-17; each were downregulated in Smox−/− mice. In DSS colitis, increased levels of IL-6, CSF3, and IL-17 were further increased in Smox−/− mice. In both models, putrescine and spermidine were increased in WT mice; in Smox−/− mice, the main effect was decreased spermidine and spermidine/spermine ratio. With C. rodentium, polyamine levels correlated with histologic injury, while with DSS, spermidine was inversely correlated with injury. Our studies indicate that SMOX has immunomodulatory effects in experimental colitis via polyamine flux. Thus, SMOX contributes to the immunopathogenesis of C. rodentium infection, but is protective in DSS colitis, indicating the divergent effects of spermidine.
Arginine and Polyamines Fate in Leishmania Infection
Muxel, Sandra M.; Aoki, Juliana I.; Fernandes, Juliane C. R.; Laranjeira-Silva, Maria F.; Zampieri, Ricardo A.; Acuña, Stephanie M.; Müller, Karl E.; Vanderlinde, Rubia H.; Floeter-Winter, Lucile M.
2018-01-01
Leishmania is a protozoan parasite that alternates its life cycle between the sand fly and the mammalian host macrophages, involving several environmental changes. The parasite responds to these changes by promoting a rapid metabolic adaptation through cellular signaling modifications that lead to transcriptional and post-transcriptional gene expression regulation and morphological modifications. Molecular approaches such as gene expression regulation, next-generation sequencing (NGS), microRNA (miRNA) expression profiling, in cell Western blot analyses and enzymatic activity profiling, have been used to characterize the infection of murine BALB/c and C57BL/6 macrophages, as well as the human monocytic cell-lineage THP-1, with Leishmania amazonensis wild type (La-WT) or arginase knockout (La-arg-). These models are being used to elucidate physiological roles of arginine and polyamines pathways and the importance of arginase for the establishment of the infection. In this review, we will describe the main aspects of Leishmania-host interaction, focusing on the arginine and polyamines pathways and pointing to possible targets to be used for prognosis and/or in the control of the infection. The parasite enzymes, arginase and nitric oxide synthase-like, have essential roles in the parasite survival and in the maintenance of infection. On the other hand, in mammalian macrophages, defense mechanisms are activated inducing alterations in the mRNA, miRNA and enzymatic profiles that lead to the control of infection. Furthermore, the genetic background of both parasite and host are also important to define the fate of infection. PMID:29379478
NASA Technical Reports Server (NTRS)
Rajam, M. V.; Galston, A. W.
1985-01-01
We have studied the effects of two polyamine biosynthetic inhibitors, alpha-difluoromethylornithine (DFMO) and alpha-difluoromethylarginine (DFMA), and of polyamines (PAs), alone and in combination, on mycelial growth and morphology of four phytopathogenic fungi: Botrytis sp, B. cinerea, Rhizoctonia solani and Monilinia fructicola. The inhibitors were added to a Czapek agar medium to get final concentrations of 0.1, 0.5 and 1.0 mM. DFMO and DFMA, suicide inhibitors of ornithine decarboxylase (ODC) and arginine decarboxylase (ADC) respectively, inhibited mycelial growth strongly; the effect was generally more pronounced with DFMA than with DFMO, but each fungus had its own response pattern. The addition of the PAs putrescine (Put) and spermidine (Spd) to the culture medium resulted in a promotion of growth. In Botrytis sp and Monilinia fructicola exposed to inhibitors plus PAs, mycelial growth was actually increased above control values. Mycelial morphology was altered and cell size dramatically reduced in plates containing inhibitors alone, whereas with PAs alone, or in combination with inhibitors, morphology was normal, but cell length and diameters increased considerably. These results suggest that PAs are essential for growth in fungal mycelia. The inhibition caused by DFMA may be due to its arginase-mediated conversion to DFMO.
Kobayashi, Kazuya; Horii, Yuichiro; Watanabe, Satoshi; Kubo, Yuji; Koguchi, Kumiko; Hoshi, Yoshihiro; Matsumoto, Ken-Ichi; Soda, Kuniyasu
2017-03-01
Polyamines have beneficial properties to prevent aging-associated diseases. Raw soybean has relatively high polyamine contents; and the fermented soybean natto is a good source of polyamines. However, detailed information of diversity of polyamine content in raw soybean is lacking. The objectives of this study were to evaluate differences of polyamines among raw soybeans and select the high polyamine-containing cultivar for natto production. Polyamine contents were measured chromatographically in 16 samples of soybean, which showed high variation among soybeans as follows: 93-861 nmol/g putrescine, 1055-2306 nmol/g spermidine, and 177-578 nmol/g spermine. We then confirmed the high correlations of polyamine contents between raw soybean and natto (r = 0.96, 0.95, and 0.94 for putrescine, spermidine, and spermine, respectively). Furthermore, comparison of the polyamine contents among 9 Japanese cultivars showed that 'Nakasen-nari' has the highest polyamine contents, suggesting its suitability for enhancement of polyamine contents of natto.
1994-06-30
conversion, the increase was faster than at later stages. and therefore the steric strain enfosced by the 5gn backone dpdson Th efficiency of initation...BPOJ),- 0.25M. Cr(OAc)2jDPO, THF. 200CC IVAclo - SMK [Cr2io - [DPOJ~i 0.25M. (UI - (Cr2+’Jo (LIgl - (Cr2 0 _ In the absence of any liganda, a
Amri, E Z; Dani, C; Doglio, A; Etienne, J; Grimaldi, P; Ailhaud, G
1986-01-01
A subclone of preadipocyte Ob17 cells has been isolated (Ob1754 clonal line). Confluent Ob1754 cells treated with an inhibitor of spermidine and spermine synthesis, methylglyoxal bis(guanylhydrazone), were totally dependent upon putrescine addition for the expression of glycerol-3-phosphate dehydrogenase which behaved as a late marker of adipose conversion. Under these conditions, the early expression of lipoprotein lipase during growth arrest remained unchanged. Studies at the mRNA level showed that the expression of unidentified pOb24 and pGH3 mRNAs, which was parallel to that of lipoprotein lipase, is independent of polyamine addition whereas the late emergence of glycerol-3-phosphate dehydrogenase mRNA was putrescine-dependent and co-ordinated with the expression of pAL422 mRNA encoding for a myelin-P2 homologue [Bernlohr, Angus, Lane, Bolanowski & Kelly (1984) Proc. Natl. Acad. Sci. U.S.A. 81, 5468-5472]. The appearance of lipoprotein lipase preceded DNA synthesis and post-confluent mitoses which were both putrescine-dependent and which took place before the appearance of glycerol-3-phosphate dehydrogenase. Thus the adipose conversion of Ob1754 cells involves the expression of at least two separate sets of markers which are differently regulated. Images Fig. 3. Fig. 6. PMID:3800927
Wu, Yu; Steinbergs, Nora; Murray-Stewart, Tracy; Marton, Laurence J.; Casero, Robert A.
2011-01-01
Epigenetic gene silencing is an important mechanism in the initiation and progression of cancer. Abnormal DNA CpG island hypermethylation and histone modifications are involved in aberrant silencing of tumour-suppressor genes. LSD1 (lysine-specific demethylase 1) was the first enzyme identified to specifically demethylate H3K4 (Lys4 of histone H3). Methylated H3K4 is an important mark associated with transcriptional activation. The flavin adenine dinucleotide-binding amine oxidase domain of LSD1 is homologous with two polyamine oxidases, SMO (spermine oxidase) and APAO (N1-acetylpolyamine oxidase). We have demonstrated previously that long-chain polyamine analogues, the oligoamines, are inhibitors of LSD1. In the present paper we report the synergistic effects of specific oligoamines in combination with DFMO (2-difluoromethylornithine), an inhibitor of ornithine decarboxylase, in human colorectal cancer cells. DFMO treatment depletes natural polyamines and increases the uptake of exogenous polyamines. The combination of oligoamines and DFMO results in a synergistic re-expression of aberrantly silenced tumour-suppressor genes, including SFRP2 (secreted frizzled-related protein 2), which encodes a Wnt signalling pathway antagonist and plays an anti-tumorigenic role in colorectal cancer. The treatment-induced re-expression of SFRP2 is associated with increased H3K4me2 (di-methyl H3K4) in the gene promoter. The combination of LSD1-inhibiting oligoamines and DFMO represents a novel approach to epigenetic therapy of cancer. PMID:22132744
Saccharomyces boulardii CNCM I-745 Improves Intestinal Enzyme Function: A Trophic Effects Review
Moré, Margret I; Vandenplas, Yvan
2018-01-01
Several properties of the probiotic medicinal yeast Saccharomyces boulardii CNCM I-745 contribute to its efficacy to prevent or treat diarrhoea. Besides immunologic effects, pathogen-binding and anti-toxin effects, as well as positive effects on the microbiota, S boulardii CNCM I-745 also has pronounced effects on digestive enzymes of the brush border membrane, known as trophic effects. The latter are the focus of this review. Literature has been reviewed after searching Medline and PMC databases. All relevant non-clinical and clinical studies are summarized. S. boulardii CNCM I-745 synthesizes and secretes polyamines, which have a role in cell proliferation and differentiation. The administration of polyamines or S. boulardii CNCM I-745 enhances the expression of intestinal digestive enzymes as well as nutrient uptake transporters. The signalling mechanisms leading to enzyme activation are not fully understood. However, polyamines have direct nucleic acid–binding capacity with regulatory impact. S. boulardii CNCM I-745 induces signalling via the mitogen-activated protein kinase pathway. In addition, effects on the phosphatidylinositol-3 kinase (PI3K) pathway have been reported. As an additional direct effect, S. boulardii CNCM I-745 secretes certain enzymes, which enhance nutrient acquisition for the yeast and the host. The increased availability of digestive enzymes seems to be one of the mechanisms by which S. boulardii CNCM I-745 counteracts diarrhoea; however, also people with certain enzyme deficiencies may profit from its administration. More studies are needed to fully understand the mechanisms of trophic activation by the probiotic yeast. PMID:29449779
Saccharomyces boulardii CNCM I-745 Improves Intestinal Enzyme Function: A Trophic Effects Review.
Moré, Margret I; Vandenplas, Yvan
2018-01-01
Several properties of the probiotic medicinal yeast Saccharomyces boulardii CNCM I-745 contribute to its efficacy to prevent or treat diarrhoea. Besides immunologic effects, pathogen-binding and anti-toxin effects, as well as positive effects on the microbiota, S boulardii CNCM I-745 also has pronounced effects on digestive enzymes of the brush border membrane, known as trophic effects. The latter are the focus of this review. Literature has been reviewed after searching Medline and PMC databases. All relevant non-clinical and clinical studies are summarized. S. boulardii CNCM I-745 synthesizes and secretes polyamines, which have a role in cell proliferation and differentiation. The administration of polyamines or S. boulardii CNCM I-745 enhances the expression of intestinal digestive enzymes as well as nutrient uptake transporters. The signalling mechanisms leading to enzyme activation are not fully understood. However, polyamines have direct nucleic acid-binding capacity with regulatory impact. S. boulardii CNCM I-745 induces signalling via the mitogen-activated protein kinase pathway. In addition, effects on the phosphatidylinositol-3 kinase (PI3K) pathway have been reported. As an additional direct effect, S. boulardii CNCM I-745 secretes certain enzymes, which enhance nutrient acquisition for the yeast and the host. The increased availability of digestive enzymes seems to be one of the mechanisms by which S. boulardii CNCM I-745 counteracts diarrhoea; however, also people with certain enzyme deficiencies may profit from its administration. More studies are needed to fully understand the mechanisms of trophic activation by the probiotic yeast.
Toninello, A; Via, L D; Di Noto, V; Mancon, M
1999-12-15
This study evaluated the effect of the anticancer drug methylglyoxal-bis(guanylhydrazone) (MGBG) on the binding of the polyamine spermine to the mitochondrial membrane and its transport into the inner compartment of this organelle. Spermine binding was studied by applying a new thermodynamic treatment of ligand-receptor interactions (Di Noto et al., Macromol Theory Simul 5: 165-181, 1996). Results showed that MGBG inhibited the binding of spermine to the site competent for the first step in polyamine transport; the interaction of spermine with this site, termed S1, also mediates the inhibitory effect of the polyamine on the mitochondrial permeability transition (Dalla Via et al., Biochim Biophys Acta 1284: 247-252, 1996). In the presence of 1 mM MGBG, the binding capacity and affinity of this site were reduced by about 2.6-fold; on the contrary, the binding capacity of the S2 site, which is most likely responsible for the internalization of cytoplasmic proteins (see Dalla Via et al., reference cited above), increased by about 1.3-fold, and its binding affinity remained unaffected. MGBG also inhibited the initial rate of spermine transport in a dose-dependent manner by establishing apparently sigmoidal kinetics. Consequently, the total extent of spermine accumulation inside mitochondria was inhibited. This inhibition in transport seems to reflect a conformational change at the level of the channel protein constituting the polyamine transport system, rather than competitive inhibition at the inner active site of the channel, thereby excluding the possibility that the polyamine and drug use the same transport pathway. Furthermore, it is suggested that, in the presence of MGBG, the S2 site is able to participate in residual spermine transport. MGBG also strongly inhibits deltapH-dependent spermine efflux, resulting in a complete block in the bidirectional flux of the polyamine and its sequestration inside the matrix space. The effects of MGBG on spermine accumulation are consistent with in vivo disruption of the regulator of energy metabolism and replication of the mitochondrial genome.
Singh, Satbir; Raj, Tilak; Singh, Amarpal; Kaur, Navneet
2016-06-01
The present research work describes the comparative analysis and performance characteristics of 4-pyridine based monomer and polymer capped ZnO dye-sensitized solar cells. The N, N-dimethyl-N4-((pyridine-4yl)methylene) propaneamine (4,monomer) and polyamine-4-pyridyl Schiff base (5, polymer) dyes were synthesized through one step condensation reaction between 4-pyridinecarboxaldehyde 1 and N, N-dimethylpropylamine 2/polyamine 3. Products obtained N, N-dimethyl-N4-((pyridine-4yl)methylene)propaneamine (4) and polyamine-4-pyridyl Schiff base (5) were purified and characterized using 1H, 13C NMR, mass, IR and CHN spectroscopy. Both the dyes 4 and 5 were further coated over ZnO nanoparticles and characterized using SEM, DLS and XRD analysis. Absorption profile and emission profile was monitored using fluorescence and UV-Vis absorption spectroscopy. A thick layer of these inbuilt dye linked ZnO nanoparticles of dyes (4) and (5) was pasted on one of the conductive side of ITO glass followed with a liquid electrolyte and counter electrode of the same conductive glass. Polyamine-4-pyridyl Schiff base polymer (5) decorated dye sensitized solar cell has shown better exciting photovoltaic properties in the form of short circuit current density (J(sc) = 6.3 mA/cm2), open circuit photo voltage (V(oc) = 0.7 V), fill factor (FF = 0.736) than monomer decorated dye sensitized solar cell. Polymer dye (5) based ZnO solar cell has shown a maximum solar power to electrical conversion efficiency of 3.25%, which is enhanced by 2.16% in case of monomer dye based ZnO solar cell under AM 1.5 sun illuminations.
How polyamine synthesis inhibitors and cinnamic acid affect tropane alkaloid production.
Marconi, Patricia L; Alvarez, María A; Pitta-Alvarez, Sandra I
2007-01-01
Hairy roots of Brugmansia candida produce the tropane alkaloids scopolamine and hyoscyamine. In an attempt to divert the carbon flux from competing pathways and thus enhance productivity, the polyamine biosynthesis inhibitors cyclohexylamine (CHA) and methylglyoxal-bis-guanylhydrazone (MGBG) and the phenylalanine-ammonia-lyase inhibitor cinnamic acid were used. CHA decreased the specific productivity of both alkaloids but increased significantly the release of scopolamine (approx 500%) when it was added in the mid-exponential phase. However, when CHA was added for only 48 h during the exponential phase, the specific productivity of both alkaloids increased (approx 200%), favoring scopolamine. Treatment with MGBG was detrimental to growth but promoted release into the medium of both alkaloids. However, when it was added for 48 h during the exponential phase, MGBG increased the specific productivity (approx 200%) and release (250- 1800%) of both alkaloids. Cinnamic acid alone also favored release but not specific productivity. When a combination of CHA or MGBG with cinnamic acid was used, the results obtained were approximately the same as with each polyamine biosynthesis inhibitor alone, although to a lesser extent. Regarding root morphology, CHA inhibited growth of primary roots and ramification. However, it had a positive effect on elongation of lateral roots.
Saha, Jayita; Giri, Kalyan
2017-04-20
Compelling evidences anticipated the well acclamation of involvement of exogenous and endogenous polyamines (PAs) in conferring salt tolerance in plants. Intracellular PA's anabolism and catabolism should have contributed to maintain endogenous PAs homeostasis to induce stress signal networks. In this report, the evolutionary study has been conducted to reveal the phylogenetic relationship of genes encoding enzymes of the anabolic and catabolic pathway of PAs among the five plant lineages including green algae, moss, lycophyte, dicot and monocot along with their respective exon-intron structural patterns. Our results indicated that natural selection pressure had considerable influence on the ancestral PA metabolic pathway coding genes of land plants. PA metabolic genes have undergone gradual evolution by duplication and diversification process leading to subsequent structural modification through exon-intron gain and loss events to acquire specific function under environmental stress conditions. We have illuminated on the potential regulation of both the pathways by investigating the real-time expression analyses of PA metabolic pathway related enzyme coding genes at the transcriptional level in root and shoot tissues of two indica rice varieties, namely IR 36 (salt sensitive) and Nonabokra (salt-tolerant) in response to salinity in presence or absence of exogenous spermidine (Spd) treatment. Additionally, we have performed tissue specific quantification of the intracellular PAs and tried to draw probable connection between the PA metabolic pathway activation and endogenous PAs accumulation. Our results successfully enlighten the fact that how exogenous Spd in presence or absence of salt stress adjust the intracellular PA pathways to equilibrate the cellular PAs that would have been attributed to plant salt tolerance. Copyright © 2017 Elsevier B.V. All rights reserved.
Modulation of the NMDA receptor by polyamines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, K.; Romano, C.; Dichter, M.A.
1991-01-01
Results of recent biochemical and electrophysiological studies have suggested that a recognition site for polyamines exists as part of the NMDA receptor complex. The endogenous polyamines spermine and spermidine increase the binding of open-channel blockers and increase NMDA-elicited currents in cultured neutrons. These polyamines have been termed agonists at the polyamine recognition site. Studies of the effects of natural and synthetic polyamines on the binding of ({sup 3}H)MK-801 and on NMDA-elicited currents in cultured neurons have led to the identification of compounds classified as partial agonists, antagonists, and inverse agonists at the polyamine recognition site. Polyamines have also been foundmore » to affect the binding of ligands to the recognition sites for glutamate and glycine. However, these effects may be mediated at a site distinct from that at which polyamines act to modulate the binding of open-channel blockers. Endogenous polyamines may modulate excitatory synaptic transmission by acting at the polyamine recognition site of the NMDA receptor. This site could represent a novel therapeutic target for the treatment of ischemia-induced neurotoxicity, epilepsy, and neurodegenerative diseases.« less
Berrak, Özge; Akkoç, Yunus; Arısan, Elif Damla; Çoker-Gürkan, Ajda; Obakan-Yerlikaya, Pınar; Palavan-Ünsal, Narçin
2016-02-01
Bcl-2 protein has been contributed with number of genes which are involved in oncogenesis. Among the many targets of Bcl-2, NFκB have potential role in induction of cell cycle arrest. Curcumin has potential therapeutic effects against breast cancer through multiple signaling pathways. In this study, we investigated the role of curcumin in induction of cell cycle arrest via regulating of NFκB and polyamine biosynthesis in wt and Bcl-2+ MCF-7 cells. To examine the effect of curcumin on cell cycle regulatory proteins, PI3K/Akt, NFκB pathways and polyamine catabolism, we performed immunoblotting assay. In addition, cell cycle analysis was performed by flow cytometry. The results indicated that curcumin induced cell cycle arrest at G2/M phase by downregulation of cyclin B1 and Cdc2 and inhibited colony formation in MCF-7wt cells. However, Bcl-2 overexpression prevented the inhibition of cell cycle associated proteins after curcumin treatment. The combination of LY294002, PI3K inhibitor, and curcumin induced cell cycle arrest by decreasing CDK4, CDK2 and cyclin E2 in Bcl-2+ MCF-7 cells. Moreover, LY294002 further inhibited the phosphorylation of Akt in Bcl-2+ MCF-7 cells. Curcumin could suppress the nuclear transport of NFκB through decreasing the interaction of P-IκB-NFκB. The combination of wedelolactone, NFκB inhibitor, and curcumin acted different on SSAT expression in wt MCF-7 and Bcl-2+ MCF-7 cells. NFκB inhibition increased the SSAT after curcumin treatment in Bcl-2 overexpressed MCF-7 cells. Inhibition of NFκB activity as well as suppression of ROS generation with NAC resulted in the partial relief of cells from G2/M checkpoint after curcumin treatment in wt MCF-7 cells. In conclusion, the potential role of curcumin in induction of cell cycle arrest is related with NFκB-regulated polyamine biosynthesis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Biomineralized 3-D Nanoparticle Assemblies with Micro-to-Nanoscale Features and Tailored Chemistries
2008-01-07
protuberances on the pollen surface were well preserved after conversion. This hybrid approach may be applied to a variety of bio-organic templates, which are...replicas were found to be rapid, low voltage, minimally-invasive sensors of NO(g) and to exhibit photoluminescence . The kinetics of magnesiothermic...silica- organic hybrid structures via biomimetic silicification has been demonstrated. The effects of two key parameters, the polyamine content and
Putrescine overproduction negatively impacts the oxidative state of poplar cells in culture
Sridev Mohapatra; Rakesh Minocha; Stephanie Long
2009-01-01
While polyamines (PAs) have been suggested to protect cells against Reactive Oxygen Species (ROS), their catabolism is known to generate ROS. We compared the activities of several enzymes and cellular metabolites involved in the ROS scavenging pathways in two isogenic cell lines of poplar (Populus nigra × maximowiczii) differing in their PA...
Sugiyama, Yuta; Nara, Misaki; Sakanaka, Mikiyasu; Gotoh, Aina; Kitakata, Aya; Okuda, Shujiro; Kurihara, Shin
2017-12-01
Recent studies have reported that polyamines in the colonic lumen might affect animal health and these polyamines are thought to be produced by gut bacteria. In the present study, we measured the concentrations of three polyamines (putrescine, spermidine, and spermine) in cells and culture supernatants of 32 dominant human gut bacterial species in their growing and stationary phases. Combining polyamine concentration analysis in culture supernatant and cells with available genomic information showed that novel polyamine biosynthetic proteins and transporters were present in dominant human gut bacteria. Based on these findings, we suggested strategies for optimizing polyamine concentrations in the human colonic lumen via regulation of genes responsible for polyamine biosynthesis and transport in the dominant human gut bacteria. Copyright © 2017 Elsevier Ltd. All rights reserved.
Desforges, Bénédicte; Curmi, Patrick A.; Bounedjah, Ouissame; Nakib, Samir; Hamon, Loic; De Bandt, Jean-Pascal; Pastré, David
2013-01-01
In the organism, quiescent epithelial cells have the potential to resume cycling as a result of various stimuli, including wound healing or oxidative stress. Because quiescent cells have a low polyamine level, resuming their growth requires an increase of their intracellular polyamine levels via de novo polyamine synthesis or their uptake from plasma. Another alternative, explored here, is an intercellular exchange with polyamine-rich cycling cells via gap junctions. We show that polyamines promote gap junction communication between proliferating cells by promoting dynamical microtubule plus ends at the cell periphery and thus allow polyamine exchange between cells. In this way, cycling cells favor regrowth in adjacent cells deprived of polyamines. In addition, intercellular interactions mediated by polyamines can coordinate the translational response to oxidative stress through the formation of stress granules. Some putative in vivo consequences of polyamine-mediated intercellular interactions are also discussed regarding cancer invasiveness and tissue regeneration. PMID:23515223
Potential Applications of Polyamines in Agriculture and Plant Biotechnology.
Tiburcio, Antonio F; Alcázar, Rubén
2018-01-01
The polyamines putrescine, spermidine and spermine have been implicated in a myriad of biological functions in many organisms. Research done during the last decades has accumulated a large body of evidence demonstrating that polyamines are key modulators of plant growth and development. Different experimental approaches have been employed including the measurement of endogenous polyamine levels and the activities of polyamine metabolic enzymes, the study of the effects resulting from exogenous polyamine applications and chemical or genetic manipulation of endogenous polyamine titers. This chapter reviews the role of PAs in seed germination, root development, plant architecture, in vitro plant regeneration, flowering and plant senescence. Evidence presented here indicates that polyamines should be regarded as plant growth regulators with potential applications in agriculture and plant biotechnology.
Burns, Mark R.; Graminski, Gerard F.; Weeks, Reitha S.; Chen, Yan; O’Brien, Thomas G.
2009-01-01
Cancer cells can overcome the ability of polyamine biosynthesis inhibitors from completely depleting their internal polyamines by the importation polyamines from external sources. We have developed a group of lipophilic polyamine analogs that potently inhibit the cellular polyamine uptake system and greatly increase the effectiveness of polyamine depletion when used in combination with DFMO, a well-studied polyamine biosynthesis inhibitor. By the attachment of an length-optimized C16 lipophilic substituent to the epsilon-nitrogen atom of our earlier lead compound, d-Lys-Spm (5), we have produced an analog, d-Lys(C16acyl)-Spm (11) with several orders of magnitude more potent cell growth inhibition on a variety of cultured cancer cell types including breast (MDA-MB-231), prostate (PC-3), melanoma (A375) and ovarian (SK-OV-3), among others. We discuss these results in the context of a possible membrane-catalyzed interaction with the extracellular polyamine transport apparatus. The resulting novel two-drug combination therapy targeting cellular polyamine metabolism has shown exceptional efficacy against cutaneous squamous cell carcinomas (SCC) in a transgenic ornithine decarboxylase (ODC) mouse model of skin cancer. A majority (88%) of large, aggressive SCCs exhibited complete or near-complete remission to this combination therapy, while responses to each agent alone were poor. The availability of a potent polyamine transport inhibitor allows, for the first time, for a real test of the hypothesis that starving cells of polyamines will lead to objective clinical response. PMID:19281226
Induction of spermidine/spermine N1-acetyltransferase by methylglyoxal bis(guanylhydrazone).
Pegg, A E; Erwin, B G; Persson, L
1985-10-17
The anti-tumor agent methylglyoxal bis(guanylhydrazone) was found to be a competitive inhibitor of spermidine/spermine N1-acetyltransferase with a Ki of about 8 microM. Treatment of rats with this drug lead to a very large increase in the total amount of spermidine/spermine N1-acetyltransferase in liver, kidney and spleen. The total increase as measured using a specific antiserum amounted to 700-fold in liver and 100-fold in kidney within 18 h of treatment with 80 mg/kg doses. At least part of this induction was due to a pronounced increase in the half-life of the acetyltransferase which increased from 15 min to more than 12 h. The very large increase in the amount of the enzyme is likely to overwhelm the direct inhibition, and a net increase in the acetylation of polyamines by this enzyme would be expected to occur after treatment with methylglyoxal bis(guanylhydrazone). The acetylated polyamines are known to be rapidly degraded by polyamine oxidase producing putrescine. Direct evidence that a substantial part of the increase in the content of putrescine in the liver of rats treated with methylglyoxal bis(guanylhydrazone) occurs via the induction of this acetylase/oxidase pathway was obtained. These results indicate that methylglyoxal bis(guanylhydrazone) affects cellular polyamine levels not only by means of its inhibitory effect on S-adenosylmethionine decarboxylase and diamine oxidase but also by the induction of spermidine/spermine N1-acetyltransferase. They also raise the possibility that the enormous increase in this enzyme which occurs with higher doses may contribute to the very severe toxicity of methylglyoxal bis(guanylhydrazone).
Matsushika, Akinori; Nagashima, Atsushi; Goshima, Tetsuya; Hoshino, Tamotsu
2013-01-01
In the present study, comprehensive, quantitative metabolome analysis was carried out on the recombinant glucose/xylose-cofermenting S. cerevisiae strain MA-R4 during fermentation with different carbon sources, including glucose, xylose, or glucose/xylose mixtures. Capillary electrophoresis time-of-flight mass spectrometry was used to determine the intracellular pools of metabolites from the central carbon pathways, energy metabolism pathways, and the levels of twenty amino acids. When xylose instead of glucose was metabolized by MA-R4, glycolytic metabolites including 3- phosphoglycerate, 2- phosphoglycerate, phosphoenolpyruvate, and pyruvate were dramatically reduced, while conversely, most pentose phosphate pathway metabolites such as sedoheptulose 7- phosphate and ribulose 5-phosphate were greatly increased. These results suggest that the low metabolic activity of glycolysis and the pool of pentose phosphate pathway intermediates are potential limiting factors in xylose utilization. It was further demonstrated that during xylose fermentation, about half of the twenty amino acids declined, and the adenylate/guanylate energy charge was impacted due to markedly decreased adenosine triphosphate/adenosine monophosphate and guanosine triphosphate/guanosine monophosphate ratios, implying that the fermentation of xylose leads to an inefficient metabolic state where the biosynthetic capabilities and energy balance are severely impaired. In addition, fermentation with xylose alone drastically increased the level of citrate in the tricarboxylic acid cycle and increased the aromatic amino acids tryptophan and tyrosine, strongly supporting the view that carbon starvation was induced. Interestingly, fermentation with xylose alone also increased the synthesis of the polyamine spermidine and its precursor S-adenosylmethionine. Thus, differences in carbon substrates, including glucose and xylose in the fermentation medium, strongly influenced the dynamic metabolism of MA-R4. These results provide a metabolic explanation for the low ethanol productivity on xylose compared to glucose. PMID:23874849
Mammalian Polyamine Metabolism and Function
Pegg, Anthony E.
2009-01-01
Summary Polyamines are ubiquitous small basic molecules that play multiple essential roles in mammalian physiology. Their cellular content is highly regulated and there is convincing evidence that altered metabolism is involvement in many disease states. Drugs altering polyamine levels may therefore have a variety of important targets. This review will summarize the current state of understanding of polyamine metabolism and function, the regulation of polyamine content, and heritable pathological conditions that may be derived from altered polyamine metabolism. PMID:19603518
Mehraein-Ghomi, Farideh; Basu, Hirak S; Church, Dawn R; Hoffmann, F Michael; Wilding, George
2010-06-01
Relatively high oxidative stress levels in the prostate are postulated to be a major factor for prostate carcinogenesis and prostate cancer (CaP) progression. We focused on elucidating metabolic pathways of oxidative stress generation in CaP cells. Previously, we showed that the transcription factor JunD is essential for androgen-induced reactive oxygen species (ROS) production in androgen-dependent human CaP cells. We also recently showed that androgen induces the first and regulatory enzyme spermidine/spermine N1-acetyltransferase (SSAT) in a polyamine catabolic pathway that produces copious amounts of metabolic ROS. Here, we present coimmunoprecipitation and Gaussia luciferase reconstitution assay data that show that JunD forms a complex with androgen-activated androgen receptor (AR) in situ. Our chromatin immunoprecipitation assay data show that JunD binds directly to a specific SSAT promoter sequence only in androgen-treated LNCaP cells. Using a vector containing a luciferase reporter gene connected to the SSAT promoter and a JunD-silenced LNCaP cell line, we show that JunD is essential for androgen-induced SSAT gene expression. The elucidation of JunD-AR complex inducing SSAT expression leading to polyamine oxidation establishes the mechanistic basis of androgen-induced ROS production in CaP cells and opens up a new prostate-specific target for CaP chemopreventive/chemotherapeutic drug development. Copyright 2010 AACR.
NASA Technical Reports Server (NTRS)
Kaur Sawhney, R.; Shekhawat, N. S.; Galston, A. W.
1985-01-01
We have previously reported that aseptically cultured mesophyll protoplasts of Vigna divide rapidly and regenerate into complete plants, while mesophyll protoplasts of Avena divide only sporadically and senesce rapidly after isolation. We measured polyamine titers in such cultures of Vigna and Avena, to study possible correlations between polyamines and cellular behavior. We also deliberately altered polyamine titer by the use of selective inhibitors of polyamine biosynthesis, noting the effects on internal polyamine titer, cell division activity and regenerative events. In Vigna cultures, levels of free and bound putrescine and spermidine increased dramatically as cell division and differentiation progressed. The increase in bound polyamines was largest in embryoid-forming callus tissue while free polyamine titer was highest in root-forming callus. In Avena cultures, the levels of total polyamines decreased as the protoplast senesced. The presence of the inhibitors alpha-difluoromethyl-arginine (specific inhibitor of arginine decarboxylase), alpha-difluoromethylornithine (specific inhibitor of ornithine decarboxylase) and dicyclohexylamine (inhibitor of spermidine synthase) reduced cell division and organogenesis in Vigna cultures. Addition of low concentration of polyamines to such cultures containing inhibitors or removal of inhibitors from the culture medium restored the progress of growth and differentiation with concomitant increase in polyamine levels.
Arginine Decarboxylase Is Localized in Chloroplasts.
Borrell, A.; Culianez-Macia, F. A.; Altabella, T.; Besford, R. T.; Flores, D.; Tiburcio, A. F.
1995-01-01
Plants, unlike animals, can use either ornithine decarboxylase or arginine decarboxylase (ADC) to produce the polyamine precursor putrescine. Lack of knowledge of the exact cellular and subcellular location of these enzymes has been one of the main obstacles to our understanding of the biological role of polyamines in plants. We have generated polyclonal antibodies to oat (Avena sativa L.) ADC to study the spatial distribution and subcellular localization of ADC protein in different oat tissues. By immunoblotting and immunocytochemistry, we show that ADC is organ specific. By cell fractionation and immunoblotting, we show that ADC is localized in chloroplasts associated with the thylakoid membrane. The results also show that increased levels of ADC protein are correlated with high levels of ADC activity and putrescine in osmotically stressed oat leaves. A model of compartmentalization for the arginine pathway and putrescine biosynthesis in active photosynthetic tissues has been proposed. In the context of endosymbiote-driven metabolic evolution in plants, the location of ADC in the chloroplast compartment may have major evolutionary significance, since it explains (a) why plants can use two alternative pathways for putrescine biosynthesis and (b) why animals do not possess ADC. PMID:12228631
Polyamines in foods: development of a food database
Ali, Mohamed Atiya; Poortvliet, Eric; Strömberg, Roger; Yngve, Agneta
2011-01-01
Background Knowing the levels of polyamines (putrescine, spermidine, and spermine) in different foods is of interest due to the association of these bioactive nutrients to health and diseases. There is a lack of relevant information on their contents in foods. Objective To develop a food polyamine database from published data by which polyamine intake and food contribution to this intake can be estimated, and to determine the levels of polyamines in Swedish dairy products. Design Extensive literature search and laboratory analysis of selected Swedish dairy products. Polyamine contents in foods were collected using an extensive literature search of databases. Polyamines in different types of Swedish dairy products (milk with different fat percentages, yogurt, cheeses, and sour milk) were determined using high performance liquid chromatography (HPLC) equipped with a UV detector. Results Fruits and cheese were the highest sources of putrescine, while vegetables and meat products were found to be rich in spermidine and spermine, respectively. The content of polyamines in cheese varied considerably between studies. In analyzed Swedish dairy products, matured cheese had the highest total polyamine contents with values of 52.3, 1.2, and 2.6 mg/kg for putrescine, spermidine, and spermine, respectively. Low fat milk had higher putrescine and spermidine, 1.2 and 1.0 mg/kg, respectively, than the other types of milk. Conclusions The database aids other researchers in their quest for information regarding polyamine intake from foods. Connecting the polyamine contents in food with the Swedish Food Database allows for estimation of polyamine contents per portion. PMID:21249159
Modulation of protein synthesis by polyamines.
Igarashi, Kazuei; Kashiwagi, Keiko
2015-03-01
Polyamines are ubiquitous small basic molecules that play important roles in cell growth and viability. Since polyamines mainly exist as a polyamine-RNA complex, we looked for proteins whose synthesis is preferentially stimulated by polyamines at the level of translation, and thus far identified 17 proteins in Escherichia coli and 6 proteins in eukaryotes. The mechanisms of polyamine stimulation of synthesis of these proteins were investigated. In addition, the role of eIF5A, containing hypusine formed from spermidine, on protein synthesis is described. These results clearly indicate that polyamines and eIF5A contribute to cell growth and viability through modulation of protein synthesis. © 2015 International Union of Biochemistry and Molecular Biology.
Polyamines and Nonmelanoma Skin Cancer
Gilmour, Susan K.
2007-01-01
Elevated levels of polyamines have long been associated with skin tumorigenesis. Tightly regulated metabolism of polyamines is critical for cell survival and normal skin homeostasis, and these controls are dysregulated in skin tumorigenesis. A key enzyme in polyamine biosynthesis, ornithine decarboxylase (ODC) is upregulated in skin tumors compared to normal skin. Use of transgenic mouse models has demonstrated that polyamines play an essential role in the early promotional phase of skin tumorigenesis. The formation of skin tumors in these transgenic mice is dependent upon polyamine biosynthesis, especially putrescine, since treatment with inhibitors of ODC activity blocks the formation of skin tumors and causes the rapid regression of existing tumors. Although the mechanism by which polyamines promote skin tumorigenesis are not well understood, elevated levels of polyamines have been shown to stimulate epidermal proliferation, alter keratinocyte differentiation status, increase neovascularization, and increase synthesis of extracellular matrix proteins in a manner similar to that seen in wound healing. It is becoming increasingly apparent that elevated polyamine levels activate not only epidermal cells but also underlying stromal cells in the skin to promote the development and progression of skin tumors. The inhibition of polyamine biosynthesis has potential to be an effective chemoprevention strategy for nonmelanoma skin cancer. PMID:17234230
A role for polyamines in glucose-stimulated insulin-gene expression.
Welsh, N
1990-01-01
The aim of the present study was to evaluate the possible role for polyamines in the glucose regulation of the metabolism of insulin mRNA of pancreatic islet cells. For this purpose islets were prepared from adult mice and cultured for 2 days in culture medium RPMI 1640 containing 3.3 mM- or 16.7 mM-glucose with or without the addition of the inhibitors of polyamine biosynthesis difluoromethylornithine (DFMO) and ethylglyoxal bis(guanylhydrazone) (EGBG). Culture at the high glucose concentration increased the islet contents of both insulin mRNA and polyamines. The synthesis of total RNA, total islet polyamines and polyamines associated with islet nuclei was also increased. When the combination of DFMO and EGBG was added in the presence of 16.7 mM-glucose, low contents of insulin mRNA, spermine and spermidine were observed. Total islet polyamine synthesis was also depressed by DFMO + EGBG, unlike islet biosynthesis of polyamines associated with nuclei, which was not equally decreased by the polyamine-synthesis inhibitors. Total RNA synthesis and turnover was not affected by DFMO + EGBG. Finally, actinomycin D attenuated the glucose-induced enhancement of insulin mRNA, and cycloheximide counteracted the insulin-mRNA attenuation induced by inhibition of polyamine synthesis. It is concluded that the glucose-induced increase in insulin mRNA is paralleled by increased contents and rates of polyamine biosynthesis and that an attenuation of the increase in polyamines prevents the increase in insulin mRNA. In addition, the results are compatible with the view that polyamines exert their effects on insulin mRNA mainly by increasing the stability of this messenger. PMID:2241922
[The effect of polyamines on lysosome fusion with phagosomes in mouse peritoneal macrophages].
Mozhenok, T P; Bulychev, A G; Braun, A D
1990-01-01
The influence of polyamines on the phagosome-lysosome fusion in murine peritoneal macrophages and on polymerization of G-actin from the rabbit muscle in vitro has been studied. Both natural polyamines (spermin, spermidin, putrescin) and synthetic phenyl derivates of polyamines (3,3'-diaminobensidin, 1,5-naphtalin diamine, 4,4'-diaminodiphenilmetan, dancylcadaverin) were used. Unlike the phenyl derivates of polyamines and putrescin, spermin and spermidin stimulate the phagosome-lysosome fusion to induce G-actin polymerization. Possible mechanisms of action of the above polyamines are discussed.
NASA Technical Reports Server (NTRS)
Kaur-Sawhney, R.; Dai, Y. R.; Galston, A. W.
1986-01-01
When gibberellic acid (GA3) is sprayed on 9-day-old light-brown dwarf Progress pea (Pisum sativum) seedlings, arginine decarboxylase (ADC; EC 4.1.1.9) activity increases within 3 h and peaks at about 9 h after GA3 application. This is followed by a second lower peak at about 30 h; both peaks were higher than the corresponding peaks in the controls. In contrast, no appreciable effect of GA3 on internode length was observed until about 12 h, after which time a dramatic increase in growth rate occurred and persisted for about 12 h. Specific (DL-alpha-difluoromethylarginine) and non-specific (D-arginine and L-canavanine) inhibitors of ADC strongly inhibited ADC activity and to a lesser extent internode growth. The inhibition was reversed only slightly by the addition of polyamines. Actinomycin D and cycloheximide inhibited the rise in ADC activity induced by GA3. The half-life of the enzyme was increased by GA3 treatment. The results suggest that part of the GA3-induced increase in internode growth may result from enhanced polyamine biosynthesis through the ADC pathway. Furthermore, the GA3 induced increase in ADC activity probably requires de novo synthesis of both RNA and protein.
2005-01-01
Extreme thermophiles produce two types of unusual polyamine: long linear polyamines such as caldopentamine and caldohexamine, and branched polyamines such as quaternary ammonium compounds [e.g. tetrakis(3-aminopropyl)ammonium]. To clarify the physiological roles of long linear and branched polyamines in thermophiles, we synthesized them chemically and tested their effects on the stability of ds (double-stranded) and ss (single-stranded) DNAs and tRNA in response to thermal denaturation, as measured by differential scanning calorimetry. Linear polyamines stabilized dsDNA in proportion to the number of amino nitrogen atoms within their molecular structure. We used the empirical results to derive formulae that estimate the melting temperature of dsDNA in the presence of polyamines of a particular molecular composition. ssDNA and tRNA were stabilized more effectively by tetrakis(3-aminopropyl)ammonium than any of the other polyamines tested. We propose that long linear polyamines are effective to stabilize DNA, and tetrakis(3-aminopropyl)ammonium plays important roles in stabilizing RNAs in thermophile cells. PMID:15673283
Overproduction of cardiac S-adenosylmethionine decarboxylase in transgenic mice
Nisenberg, Oleg; Pegg, Anthony E.; Welsh, Patricia A.; Keefer, Kerry; Shantz, Lisa M.
2005-01-01
The present study was designed to provide a better understanding of the role played by AdoMetDC (S-adenosylmethionine decarboxylase), the key rate-controlling enzyme in the synthesis of spermidine and spermine, in controlling polyamine levels and the importance of polyamines in cardiac physiology. The αMHC (α-myosin heavy chain) promoter was used to generate transgenic mice with cardiac-specific expression of AdoMetDC. A founder line (αMHC/AdoMetDC) was established with a >100-fold increase in AdoMetDC activity in the heart. Transgene expression was maximal by 1 week of age and remained constant into adulthood. However, the changes in polyamine levels were most pronounced during the first week of age, with a 2-fold decrease in putrescine and spermidine and a 2-fold increase in spermine. At later times, spermine returned to near control levels, whereas putrescine and spermidine levels remained lower, suggesting that compensatory mechanisms exist to limit spermine accumulation. The αMHC/AdoMetDC mice did not display an overt cardiac phenotype, but there was an increased cardiac hypertrophy after β-adrenergic stimulation with isoprenaline (‘isoproterenol’), as well as a small increase in spermine content. Crosses of the αMHC/AdoMetDC with αMHC/ornithine decarboxylase mice that have a >1000-fold increase in cardiac ornithine decarboxylase were lethal in utero, presumably due to increase in spermine to toxic levels. These findings suggest that cardiac spermine levels are highly regulated to avoid polyamine-induced toxicity and that homoeostatic mechanisms can maintain non-toxic levels even when one enzyme of the biosynthetic pathway is greatly elevated but are unable to do so when two biosynthetic enzymes are increased. PMID:16153183
Murray-Stewart, Tracy; Wang, Yanlin; Goodwin, Andrew; Hacker, Amy; Meeker, Alan; Casero, Robert A.
2013-01-01
The recent discovery of the direct oxidation of spermine via spermine oxidase (SMO) as a mechanism through which specific antitumor polyamine analogues exert their cytotoxic effects has fueled interest in the study of the polyamine catabolic pathway. A major byproduct of spermine oxidation is H2O2, a source of toxic reactive oxygen species. Recent targeted small interfering RNA studies have confirmed that SMO-produced reactive oxygen species are directly responsible for oxidative stress capable of inducing apoptosis and potentially mutagenic DNA damage. In the present study, we describe a second catalytically active splice variant protein of the human spermine oxidase gene, designated SMO5, which exhibits substrate specificities and affinities comparable to those of the originally identified human spermine oxidase-1, SMO/PAOh1, and, as such, is an additional source of H2O2. Importantly, overexpression of either of these SMO isoforms in NCI-H157 human non-small cell lung carcinoma cells resulted in significant localization of SMO protein in the nucleus, as determined by confocal microscopy. Furthermore, cell lines overexpressing either SMO/PAOh1 or SMO5 demonstrated increased spermine oxidation in the nucleus, with accompanying alterations in individual nuclear polyamine concentrations. This increased oxidation of spermine in the nucleus therefore increases the production of highly reactive H2O2 in close proximity to DNA, as well as decreases nuclear spermine levels, thus altering the protective roles of spermine in free radical scavenging and DNA shielding, and resulting in an overall increased potential for oxidative DNA damage in these cells. The results of these studies therefore have considerable significance both with respect to targeting polyamine oxidation as an antineoplastic strategy, and in regard to the potential role of spermine oxidase in inflammation-induced carcinogenesis. PMID:18422650
A systems analysis of the chemosensitivity of breast cancer cells to the polyamine analogue PG-11047
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuo, Wen-Lin; Das, Debopriya; Ziyad, Safiyyah
2009-11-14
Polyamines regulate important cellular functions and polyamine dysregulation frequently occurs in cancer. The objective of this study was to use a systems approach to study the relative effects of PG-11047, a polyamine analogue, across breast cancer cells derived from different patients and to identify genetic markers associated with differential cytotoxicity. A panel of 48 breast cell lines that mirror many transcriptional and genomic features present in primary human breast tumours were used to study the antiproliferative activity of PG-11047. Sensitive cell lines were further examined for cell cycle distribution and apoptotic response. Cell line responses, quantified by the GI50 (dosemore » required for 50% relative growth inhibition) were correlated with the omic profiles of the cell lines to identify markers that predict response and cellular functions associated with drug sensitivity. The concentrations of PG-11047 needed to inhibit growth of members of the panel of breast cell lines varied over a wide range, with basal-like cell lines being inhibited at lower concentrations than the luminal cell lines. Sensitive cell lines showed a significant decrease in S phase fraction at doses that produced little apoptosis. Correlation of the GI50 values with the omic profiles of the cell lines identified genomic, transcriptional and proteomic variables associated with response. A 13-gene transcriptional marker set was developed as a predictor of response to PG-11047 that warrants clinical evaluation. Analyses of the pathways, networks and genes associated with response to PG-11047 suggest that response may be influenced by interferon signaling and differential inhibition of aspects of motility and epithelial to mesenchymal transition.« less
Quinet, Muriel; Lefèvre, Isabelle; Lambillotte, Béatrice; Dupont-Gillain, Christine C.; Lutts, Stanley
2010-01-01
Effects of salt stress on polyamine metabolism and ethylene production were examined in two rice (Oryza sativa L.) cultivars [I Kong Pao (IKP), salt sensitive; and Pokkali, salt resistant] grown for 5 d and 12 d in nutrient solution in the presence or absence of putrescine (1 mM) and 0, 50, and 100 mM NaCl. The salt-sensitive (IKP) and salt-resistant (Pokkali) cultivars differ not only in their mean levels of putrescine, but also in the physiological functions assumed by this molecule in stressed tissues. Salt stress increased the proportion of conjugated putrescine in salt-resistant Pokkali and decreased it in the salt-sensitive IKP, suggesting a possible protective function in response to NaCl. Activities of the enzymes ornithine decarboxylase (ODC; EC 4.1.1.17) and arginine decarboxylase (ADC; EC 4.1.1.19) involved in putrescine synthesis were higher in salt-resistant Pokkali than in salt-sensitive IKP. Both enzymes were involved in the response to salt stress. Salt stress also increased diamine oxidase (DAO; 1.4.3.6) and polyamine oxidase (PAO EC 1.5.3.11) activities in the roots of salt-resistant Pokkali and in the shoots of salt-sensitive IKP. Gene expression followed by reverse transcription-PCR suggested that putrescine could have a post-translational impact on genes coding for ADC (ADCa) and ODC (ODCa and ODCb) but could induce a transcriptional activation of genes coding for PAO (PAOb) mainly in the shoot of salt-stressed plants. The salt-resistant cultivar Pokkali produced higher amounts of ethylene than the salt-sensitive cultivar IKP, and exogenous putrescine increased ethylene synthesis in both cultivars, suggesting no direct antagonism between polyamine and ethylene pathways in rice. PMID:20472577
Narayanan, S. Priya; Rojas, Modesto; Suwanpradid, Jutamas; Toque, Haroldo A.; Caldwell, R. William; Caldwell, Ruth B.
2013-01-01
Ischemic retinopathies, such as diabetic retinopathy (DR), retinopathy of prematurity and retinal vein occlusion are a major cause of blindness in developed nations worldwide. Each of these conditions is associated with early neurovascular dysfunction. However, conventional therapies target clinically significant macula edema or neovascularization, which occur much later. Intraocular injections of anti-VEGF show promise in reducing retinal edema, but the effects are usually transient and the need for repeated injections increases the risk of intraocular infection. Laser photocoagulation can control pathological neovascularization, but may impair vision and in some patients the retinopathy continues to progress. Moreover, neither treatment targets early stage disease or promotes repair. This review examines the potential role of the ureahydrolase enzyme arginase as a therapeutic target for the treatment of ischemic retinopathy. Arginase metabolizes L-arginine to form proline, polyamines and glutamate. Excessive arginase activity reduces the L-arginine supply for nitric oxide synthase (NOS), causing it to become uncoupled and produce superoxide and less NO. Superoxide and NO react and form the toxic oxidant peroxynitrite. The catabolic products of polyamine oxidation and glutamate can induce more oxidative stress and DNA damage, both of which can cause cellular injury. Studies indicate that neurovascular injury during retinopathy is associated with increased arginase expression/activity, decreased NO, polyamine oxidation, formation of superoxide and peroxynitrite and dysfunction and injury of both vascular and neural cells. Furthermore, data indicate that the cytosolic isoform arginase I (AI) is involved in hyperglycemia-induced dysfunction and injury of vascular endothelial cells whereas the mitochondrial isoform arginase II (AII) is involved in neurovascular dysfunction and death following hyperoxia exposure. Thus, we postulate that activation of the arginase pathway causes neurovascular injury by uncoupling NOS and inducing polyamine oxidation and glutamate formation, thereby reducing NO and increasing oxidative stress, all of which contribute to the retinopathic process. PMID:23830845
Andrew F. Page; Rakesh Minocha; Subhash C. Minocha
2012-01-01
Arginine (Arg) and ornithine (Orn), both derived from glutamate (Glu), are the primary substrates for polyamine (PA) biosynthesis, and also play important roles as substrates and intermediates of overall N metabolism in plants. Their cellular homeostasis is subject to multiple levels of regulation. Using reverse transcription quantitative PCR (RT-qPCR), we studied...
Biochemical evaluation of the anticancer potential of the polyamine-based nanocarrier Nano11047.
Murray-Stewart, Tracy; Ferrari, Elena; Xie, Ying; Yu, Fei; Marton, Laurence J; Oupicky, David; Casero, Robert A
2017-01-01
Synthesizing polycationic polymers directly from existing drugs overcomes the drug-loading limitations often associated with pharmacologically inert nanocarriers. We recently described nanocarriers formed from a first-generation polyamine analogue, bis(ethyl)norspermine (BENSpm), that could simultaneously target polyamine metabolism while delivering therapeutic nucleic acids. In the current study, we describe the synthesis and evaluation of self-immolative nanocarriers derived from the second-generation polyamine analogue PG-11047. Polyamines are absolutely essential for proliferation and their metabolism is frequently dysregulated in cancer. Through its effects on polyamine metabolism, PG-11047 effectively inhibits tumor growth in cancer cell lines of multiple origins as well as in human tumor mouse xenografts. Promising clinical trials have been completed verifying the safety and tolerance of this rotationally restricted polyamine analogue. We therefore used PG-11047 as the basis for Nano11047, a biodegradable, prodrug nanocarrier capable of targeting polyamine metabolism. Following exposure of lung cancer cell lines to Nano11047, uptake and intracellular degradation into the parent compound PG-11047 was observed. The release of PG-11047 highly induced the polyamine catabolic enzyme activities of spermidine/spermine N1-acetyltransferase (SSAT) and spermine oxidase (SMOX). By contrast, the activity of ornithine decarboxylase (ODC), a rate-limiting enzyme in polyamine biosynthesis and a putative oncogene, was decreased. Consequently, intracellular levels of the natural polyamines were depleted concurrent with tumor cell growth inhibition. This availability of Nano11047 as a novel drug form and potential nucleic acid delivery vector will potentially benefit and encourage future clinical studies.
Polyamine uptake by the intraerythrocytic malaria parasite, Plasmodium falciparum.
Niemand, J; Louw, A I; Birkholtz, L; Kirk, K
2012-09-01
Polyamines and the enzymes involved in their biosynthesis are present at high levels in rapidly proliferating cells, including cancer cells and protozoan parasites. Inhibition of polyamine biosynthesis in asexual blood-stage malaria parasites causes cytostatic arrest of parasite development under in vitro conditions, but does not cure infections in vivo. This may be due to replenishment of the parasite's intracellular polyamine pool via salvage of exogenous polyamines from the host. However, the mechanism(s) of polyamine uptake by the intraerythrocytic parasite are not well understood. In this study, the uptake of the polyamines, putrescine and spermidine, into Plasmodium falciparum parasites functionally isolated from their host erythrocyte was investigated using radioisotope flux techniques. Both putrescine and spermidine were taken up into isolated parasites via a temperature-dependent process that showed cross-competition between different polyamines. There was also some inhibition of polyamine uptake by basic amino acids. Inhibition of polyamine biosynthesis led to an increase in the total amount of putrescine and spermidine taken up from the extracellular medium. The uptake of putrescine and spermidine by isolated parasites was independent of extracellular Na(+) but increased with increasing external pH. Uptake also showed a marked dependence on the parasite's membrane potential, decreasing with membrane depolarization and increasing with membrane hyperpolarization. The data are consistent with polyamines being taken up into the parasite via an electrogenic uptake process, energised by the parasite's inwardly negative membrane potential. Copyright © 2012 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
Polyamine Uptake in Carrot Cell Cultures 1
Pistocchi, Rossella; Bagni, Nello; Creus, José A.
1987-01-01
Putrescine and spermidine uptake into carrot (Daucus carota L.) cells in culture was studied. The time course of uptake showed that the two polyamines were very quickly transported into the cells, reaching a maximum absorption within 1 minute. Increasing external polyamine concentrations up to 100 millimolar showed the existence of a biphasic system with different affinities at low and high polyamine concentrations. The cellular localization of absorbed polyamines was such that a greater amount of putrescine was present in the cytoplasmic soluble fraction, while spermidine was mostly present in cell walls. The absorbed polyamines were released into the medium in the presence of increasing external concentrations of the corresponding polyamine or Ca2+. The effects of Ca2+ were different for putrescine and spermidine; putrescine uptake was slightly stimulated by 10 micromolar Ca2+ and inhibited by higher concentrations, while for spermidine uptake there was an increasing stimulation in the Ca2+ concentration range between 10 micromolar and 1 millimolar. La3+ nullified the stimulatory effect of 10 micromolar Ca2+ on putrescine uptake and that of 1 millimolar Ca2+ on spermidine uptake. La3+ at 0.5 to 1 millimolar markedly inhibited the uptake of both polyamines, suggesting that it interferes with the sites of polyamine uptake. Putrescine uptake was affected to a lesser extent by metabolic inhibitors than was spermidine uptake. It is proposed that the entry of polyamines into the cells is driven by the transmembrane electrical gradient, with a possible antiport mechanism between external and internal polyamine molecule. PMID:16665446
Cytotoxicity of polyamines to Amoeba proteus: role of polyamine oxidase.
Schenkel, E; Dubois, J G; Helson-Cambier, M; Hanocq, M
1996-02-01
It has been shown that oxidation of polyamines by polyamine oxidases can produce toxic compounds (H2O2, aldehydes, ammonia) and that the polyamine oxidase-polyamine system is implicated, in vitro, in the death of several parasites. Using Amoeba proteus as an in vitro model, we studied the cytotoxicity to these cells of spermine, spermidine, their acetyl derivatives, and their hypothetical precursors. Spermine and N1-acetylspermine were more toxic than emetine, an amoebicidal reference drug. Spermine presented a short-term toxicity, but a 48-h contact time was necessary for the high toxicity of spermidine. The uptake by Amoeba cells of the different polyamines tested was demonstrated. On the other hand, a high polyamine oxidase activity was identified in Amoeba proteus crude extract. Spermine (theoretical 100%) and N1-acetylspermine (64%) were the best substrates at pH 9.5, while spermidine, its acetyl derivatives, and putrescine were very poorly oxidized by this enzyme (3-20%). Spermine oxidase activity was inhibited by phenylhydrazine (nil) and isoniazid (approximately 50%). Mepacrine did not inhibit the enzyme activity at pH 8. Neither monoamine nor diamine oxidase activity (approximately 10%) was found. It must be emphasized that spermine, the best enzyme substrate, is the most toxic polyamine. This finding suggests that knowledge of polyamine oxidase specificity can be used to modulate the cytotoxicity of polyamine derivatives. Amoeba proteus was revealed as a simple model for investigation of the connection between cytotoxicity and enzyme activity.
Moya, E; Blagbrough, I S
1996-02-01
Efficient syntheses of FTX-3.3 and sFTX-3.3, voltage-sensitive calcium channel blockers are described. These modified polyamines were prepared from selectively protected polyamines and purified on a practical scale.
Skorupski, Katherine A.; O'Brien, Thomas G.; Guerrero, Teri; Rodriguez, Carlos O.; Burns, Mark R.
2011-01-01
Polyamines are essential for cell proliferation. Their production is dysregulated in many cancers and polyamine depletion leads to tumor regression in mouse models of SCC. The purpose of this study was to determine the maximally tolerated dose of the polyamine transport inhibitor, MQT 1426, when combined with the ornithine decarboxylase inhibitor, DFMO, and to determine whether this therapy results in reduction in tumor polyamine levels. Thirteen cats with oral SCC received both drugs orally and serial tumor biopsies were obtained for polyamine measurement. Cats were monitored for response to therapy and toxicity. A maximum tolerated dose of MQT 1426 when combined with DFMO was determined. Dose limiting toxicity was vestibular in nature, but was fully reversible. Spermidine and total polyamine levels decreased significantly in tissues, 2 cats experienced objective tumor regression, and 6 cats had stable disease. These results suggest that further study of polyamine depletion therapies is warranted. PMID:22077408
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haghighi Poodeh, Saeid, E-mail: saeid.haghighi@oulu.fi; Medical Research Center, Oulu University Hospital, Oulu; Alhonen, Leena
Highlights: • Polyamine pools in embryonic and extraembryonic tissues are developmentally regulated. • Alcohol administration perturbs polyamine levels in the tissues with various patterns. • Total absence of polyamines in the embryo head at 9.5 dpc is critical for development. • The deficiency is associated with reduction in endothelial cell sprouting in the head. • Retarded migration of neural crest cells may cause development of neural tube defect. - Abstract: Introduction: Polyamines play a fundamental role during embryogenesis by regulating cell growth and proliferation and by interacting with RNA, DNA and protein. The polyamine pools are regulated by metabolism andmore » uptake from exogenous sources. The use of certain inhibitors of polyamine synthesis causes similar defects to those seen in alcohol exposure e.g. retarded embryo growth and endothelial cell sprouting. Methods: CD-1 mice received two intraperitoneal injections of 3 g/kg ethanol at 4 h intervals 8.75 days post coitum (dpc). The fetal head, trunk, yolk sac and placenta were collected at 9.5 and 12.5 dpc and polyamine concentrations were determined. Results: No measurable quantity of polyamines could be detected in the embryo head at 9.5 dpc, 12 h after ethanol exposure. Putrescine was not detectable in the trunk of the embryo at that time, whereas polyamines in yolk sac and placenta were at control level. Polyamine deficiency was associated with slow cell growth, reduction in endothelial cell sprouting, an altered pattern of blood vessel network formation and consequently retarded migration of neural crest cells and growth restriction. Discussion: Our results indicate that the polyamine pools in embryonic and extraembryonic tissues are developmentally regulated. Alcohol administration, at the critical stage, perturbs polyamine levels with various patterns, depending on the tissue and its developmental stage. The total absence of polyamines in the embryo head at 9.5 dpc may explain why this stage is so vulnerable to the development of neural tube defect, and growth restriction, the findings previously observed in fetal alcohol syndrome.« less
Pacific oyster polyamine oxidase: a protein missing link in invertebrate evolution.
Cervelli, Manuela; Polticelli, Fabio; Angelucci, Emanuela; Di Muzio, Elena; Stano, Pasquale; Mariottini, Paolo
2015-05-01
Polyamine oxidases catalyse the oxidation of polyamines and acetylpolyamines and are responsible for the polyamine interconversion metabolism in animal cells. Polyamine oxidases from yeast can oxidize spermine, N(1)-acetylspermine, and N(1)-acetylspermidine, while in vertebrates two different enzymes, namely spermine oxidase and acetylpolyamine oxidase, specifically catalyse the oxidation of spermine, and N(1)-acetylspermine/N(1)-acetylspermidine, respectively. In this work we proved that the specialized vertebrate spermine and acetylpolyamine oxidases have arisen from an ancestor invertebrate polyamine oxidase with lower specificity for polyamine substrates, as demonstrated by the enzymatic activity of the mollusc polyamine oxidase characterized here. This is the first report of an invertebrate polyamine oxidase, the Pacific oyster Crassostrea gigas (CgiPAO), overexpressed as a recombinant protein. This enzyme was biochemically characterized and demonstrated to be able to oxidase both N(1)-acetylspermine and spermine, albeit with different efficiency. Circular dichroism analysis gave an estimation of the secondary structure content and modelling of the three-dimensional structure of this protein and docking studies highlighted active site features. The availability of this pluripotent enzyme can have applications in crystallographic studies and pharmaceutical biotechnologies, including anticancer therapy as a source of hydrogen peroxide able to induce cancer cell death.
Kubo, K; Hattori, A
2001-10-01
The use of polyamines as electroosmotic modifiers has been shown to be effective in enhancing resolution of protein glycoforms in capillary zone electrophoresis (CZE) using a bare capillary tube. In this study, effectiveness was evaluated by using a polyacrylamide-coated capillary tube instead of a bare capillary tube. Electropherograms obtained in the presence of polyamines were inferior to those obtained in their absence with respect to resolution. Electrophoretic mobility of the proteins decreased and their peaks were broadened by polyamines bound to them. This unfavorable effect was dependent on both the species of polyamines and the pH values of the electrolyte buffer. The reduction of resolution caused by polyamines was in the following order: spermidine (SPD) approximately spermidine-tri-hydrochloride (SPD-HCI) > putrescine (PUT) > hexamethonium chloride (HMC). The observed effect can be ascribed to the formation of complexes between the proteins and the polyamines. In addition, for the bare capillary tube the complexes showed interaction with the inner surface, resulting in local suppression of electroosmosis and poor resolution. The high resolution obtained in the coated capillary tube was reduced in the presence of the polyamines. Thus, the use of the polyamines has a negative effect on the analysis of protein microheterogeneity as a result of protein-polyamine interaction.
Biochemical evaluation of the anticancer potential of the polyamine-based nanocarrier Nano11047
Ferrari, Elena; Xie, Ying; Yu, Fei; Marton, Laurence J.; Oupicky, David; Casero, Robert A.
2017-01-01
Synthesizing polycationic polymers directly from existing drugs overcomes the drug-loading limitations often associated with pharmacologically inert nanocarriers. We recently described nanocarriers formed from a first-generation polyamine analogue, bis(ethyl)norspermine (BENSpm), that could simultaneously target polyamine metabolism while delivering therapeutic nucleic acids. In the current study, we describe the synthesis and evaluation of self-immolative nanocarriers derived from the second-generation polyamine analogue PG-11047. Polyamines are absolutely essential for proliferation and their metabolism is frequently dysregulated in cancer. Through its effects on polyamine metabolism, PG-11047 effectively inhibits tumor growth in cancer cell lines of multiple origins as well as in human tumor mouse xenografts. Promising clinical trials have been completed verifying the safety and tolerance of this rotationally restricted polyamine analogue. We therefore used PG-11047 as the basis for Nano11047, a biodegradable, prodrug nanocarrier capable of targeting polyamine metabolism. Following exposure of lung cancer cell lines to Nano11047, uptake and intracellular degradation into the parent compound PG-11047 was observed. The release of PG-11047 highly induced the polyamine catabolic enzyme activities of spermidine/spermine N1-acetyltransferase (SSAT) and spermine oxidase (SMOX). By contrast, the activity of ornithine decarboxylase (ODC), a rate-limiting enzyme in polyamine biosynthesis and a putative oncogene, was decreased. Consequently, intracellular levels of the natural polyamines were depleted concurrent with tumor cell growth inhibition. This availability of Nano11047 as a novel drug form and potential nucleic acid delivery vector will potentially benefit and encourage future clinical studies. PMID:28423064
Chen, Ying; Kramer, Debora L; Li, Fengzhi; Porter, Carl W
2003-08-07
We have previously shown that the clinically relevant polyamine analog N1,N11-diethylnorspermine (DENSPM) causes rapid apoptosis in human melanoma SK-MEL-28 cells via a series of events that include mitochondrial release of cytochrome c and activation of the caspase cascade. Upstream to these events, DENSPM downregulates polyamine biosynthesis and potently upregulates polyamine catabolism at the level of spermidine/spermine N1-acetyltransferase (SSAT). In searching for downstream effectors that either contribute to or abrogate the apoptotic response, we observed that DENSPM treatment of SK-MEL-28 cells for 30 h led to cytosolic release of Smac/Diablo, a mitochondrial protein known to bind and inhibit the function of inhibitor of apoptosis proteins (IAPs). Subsequently, we found that DENSPM markedly lowered survivin and ML-IAP protein (but not XIAP) levels by 18 h via an apparently Smac/Diablo-independent pathway. Proteasome inhibitors fully prevented survivin and ML-IAP protein loss as well as apoptosis, suggesting that the proteasome-mediated degradation of survivin and ML-IAP is causally linked to the cellular outcome. We also observed that structural analogs of DENSPM which differentially induced SSAT and apoptosis lowered survivin and ML-IAP levels in a manner that correlated with enzyme activity. The linkage between IAPs and SSAT was more directly established by the finding that selective prevention of SSAT induction by small interfering RNA prevented survivin and ML-IAP loss as well as apoptosis during DENSPM treatment. Among the melanoma cell lines (SK-MEL-28, MALME-3M, A375 and LOX), survivin degradation correlated temporally with the onset of DENSPM induced apoptosis or growth inhibition. By contrast, ML-IAP degradation occurred only during rapid apoptosis seen in SK-MEL-28 cells. These data suggest a sequence of events whereby DENSPM induction of SSAT leads to loss of IAP proteins and a more fulminate apoptotic response. The findings implicate survivin and ML-IAP as important determinants of polyamine analog drug action in melanoma cells.
Ahn, Sun-Young; Jamshidi, Neema; Mo, Monica L.; Wu, Wei; Eraly, Satish A.; Dnyanmote, Ankur; Bush, Kevin T.; Gallegos, Tom F.; Sweet, Douglas H.; Palsson, Bernhard Ø.; Nigam, Sanjay K.
2011-01-01
The main kidney transporter of many commonly prescribed drugs (e.g. penicillins, diuretics, antivirals, methotrexate, and non-steroidal anti-inflammatory drugs) is organic anion transporter-1 (OAT1), originally identified as NKT (Lopez-Nieto, C. E., You, G., Bush, K. T., Barros, E. J., Beier, D. R., and Nigam, S. K. (1997) J. Biol. Chem. 272, 6471–6478). Targeted metabolomics in knockouts have shown that OAT1 mediates the secretion or reabsorption of many important metabolites, including intermediates in carbohydrate, fatty acid, and amino acid metabolism. This observation raises the possibility that OAT1 helps regulate broader metabolic activities. We therefore examined the potential roles of OAT1 in metabolic pathways using Recon 1, a functionally tested genome-scale reconstruction of human metabolism. A computational approach was used to analyze in vivo metabolomic as well as transcriptomic data from wild-type and OAT1 knock-out animals, resulting in the implication of several metabolic pathways, including the citric acid cycle, polyamine, and fatty acid metabolism. Validation by in vitro and ex vivo analysis using Xenopus oocyte, cell culture, and kidney tissue assays demonstrated interactions between OAT1 and key intermediates in these metabolic pathways, including previously unknown substrates, such as polyamines (e.g. spermine and spermidine). A genome-scale metabolic network reconstruction generated some experimentally supported predictions for metabolic pathways linked to OAT1-related transport. The data support the possibility that the SLC22 and other families of transporters, known to be expressed in many tissues and primarily known for drug and toxin clearance, are integral to a number of endogenous pathways and may be involved in a larger remote sensing and signaling system (Ahn, S. Y., and Nigam, S. K. (2009) Mol. Pharmacol. 76, 481–490, and Wu, W., Dnyanmote, A. V., and Nigam, S. K. (2011) Mol. Pharmacol. 79, 795–805). Drugs may alter metabolism by competing for OAT1 binding of metabolites. PMID:21757732
[Polyamines and their role in tumor growth].
Godlewska, Joanna; Peczyńska-Czoch, Wanda
2002-01-01
The polyamines-putrescine, spermidine and spermine--are normal constituents of prokariotic and eukariotic cells. These small polycationic, aliphatic compounds are essential for normal cell proliferation. Cells cease to proliferate, when they are depleted of their polyamines, but resume a normal growth rate after supplementation with these compounds. Because of the sustained increase in polyamine biosynthesis in preneoplastic and neoplastic tissues, a great deal of interest has been given to the polyamine biosynthesis, network, and uptake systems as a target in antineoplastic strategies.
Effects of stress temperatures of germination on polyamine titers of soybean seeds
NASA Astrophysics Data System (ADS)
Pineda-Mejia, Renan
High and low stress temperatures during seed germination and seedling development limit total germination and the rate of germination and growth. Changes in polyamine (PA) concentrations in seeds of different species have been associated with germination, growth and environmental stresses such as temperature, drought, oxygen, chilling injury and osmotic conditions. Two studies were conducted to determine the effect of stress temperatures during germination and seedling development on polyamine titers in soybean seeds. Three germination temperatures, 25, 30, and 36°C were used in the first study to evaluate their influence on changes in polyamine concentrations in soybean seeds germinated at 76 and 90 hours. The polyamines (PAs), cadaverine (Cad), putrescine (Put), spermidine (Spd), agmatine (Agm), and spermine (Spin) were quantified by HPLC using a cation exchange column and an electrochemical detector. Cad, Put, Agm, and Spd declined as the germination temperatures increased from 25 to 36°C. Conversely, Spin increased considerably with an increase in temperature. Total germination was reduced from 97.2 to 92.5% as germination temperatures increased from 25 to 36°C. Germination time did not affect Cad, Agm and Spm, and total germination, however, the interaction between temperature and germination time for Put and Spd concentrations was significant. In the second study, changes in PA concentrations, seedling growth, germination time (t50), fresh and dry weight, and moisture content were measured in the embryonic axis and cotyledons of soybean seeds germinated at 10 and 25°C through six stages of germination dry seed (DS), testa split (TS), radicle at 10 mm (Ra-10), root hairs visible (RHV), secondary root primordia (SRP), and complete seedling (CS). The concentrations of Cad and Put in the embryonic axis, were significantly higher in seeds germinated under low temperature than in seeds at 25°C (approximately 10 and 3 fold respectively). However, this difference was not observed until the last three stages of germination. The stage of germination also influenced the levels of these polyamines. The concentrations of Cad and Put detected at the CS stage were 50 and 18 fold respectively, relative to the initial concentrations found at the DS stage. Spd levels in seeds under stress temperatures also increased, but to a lesser extent compared to Cad and Put. Differences in Spd concentrations between temperatures were observed only at the CS stage. Agm concentrations were higher at 25 than at 10°C at SRP and CS. Spm concentrations of seeds germinated at 25°C remained higher during the first four stages of development but at the end of germination, seeds at 10°C had higher quantities of Spm. In the cotyledons, Polyamines tended to decline with stages of germination, regardless of the temperature. However, Agm levels increased in the cotyledons of soybean seeds. Maximum dry weight and seedling growth was found at RHV, SRP, and CS. Maximum levels of Cad and Put were also found during these stages. Spd increased with both temperatures from DS to Ra-10, thereafter, Spd levels in seeds at 10°C continued increasing while seeds at 25°C declined. High and low stress germination temperatures caused significant changes in polyamine concentrations, reduced germination and seedling growth of soybean seeds.
40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acid polyamine condensate... New Uses for Specific Chemical Substances § 721.6200 Fatty acid polyamine condensate, phosphoric acid... substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and P-90-1985...
40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acid polyamine condensate... New Uses for Specific Chemical Substances § 721.6200 Fatty acid polyamine condensate, phosphoric acid... substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and P-90-1985...
Polyamine-iron chelator conjugate.
Bergeron, Raymond J; McManis, James S; Franklin, April M; Yao, Hua; Weimar, William R
2003-12-04
The current study demonstrates unequivocally that polyamines can serve as vectors for the intracellular delivery of the bidentate chelator 1,2-dimethyl-3-hydroxypyridin-4-one (L1). The polyamine-hydroxypyridinone conjugate 1-(12-amino-4,9-diazadodecyl)-2-methyl-3-hydroxy-4(1H)-pyridinone is assembled from spermine and 3-O-benzylmaltol. The conjugate is shown to form a 3:1 complex with Fe(III) and to be taken up by the polyamine transporter 1900-fold against a concentration gradient. The K(i) of the conjugate is 3.7 microM vs spermidine for the polyamine transporter. The conjugate is also at least 230 times more active in suppressing the growth of L1210 murine leukemia cells than is the parent ligand, decreases the activities of the polyamine biosynthetic enzymes ornithine decarboxylase and S-adenosylmethionine decarboxylase, and upregulates spermidine-spermine N (1)-acetyltransferase. However, the effect on native polyamine pools is a moderate one. These findings are in keeping with the idea that polyamines can also serve as efficient vectors for the intracellular delivery of other iron chelators.
Effect of mitoguazone on polyamine oxidase activity in rat liver.
Ferioli, Maria Elena; Berselli, Debora; Caimi, Samuela
2004-12-01
Mitoguazone is a known inhibitor of polyamine biosynthesis through competitive inhibition of S-adenosylmethionine decarboxylase. A recent renewed interest in mitoguazone as an antineoplastic agent prompted us to investigate the effect of the drug on polyamine catabolism in rat liver, since the organ plays an important role in detoxification mechanisms. Thus, the purpose of this work was to evaluate the effect of in vivo mitoguazone administration on polyamine catabolic enzymes. In particular, our interest was directed to the changes in polyamine oxidase activity, since this enzyme has been recently confirmed to exert important functions that until now were underestimated. Mitoguazone administration induced hepatic polyamine oxidase activity starting at 4 h after administration, and the enzyme returned to basal levels 96 h after treatment. The changes in enzyme activity were accompanied by changes in putrescine concentrations, which increased starting at 4 h until 72 h after treatment. We also evaluated the activity of the newly identified spermine oxidase, which was not significantly changed by mitoguazone treatment. Therefore, we hypothesized that the enzyme involved in mitoguazone response of the liver is the polyamine oxidase, which acts on acetylated polyamines as substrate.
The early history of polyamine research.
Bachrach, Uriel
2010-07-01
In 1678 Antonie van Leeuwenhoek identified crystalline substances in human semen. The structure of these crystals, named "spermine", was not elucidated by Rosenheim until 250 years later. Subsequently a triamine (spermidine) and a diamine (putrescine; 1,4-diaminobutane) were isolated from prokaryotic and eukaryotic systems. Soon it became apparent that polyamines can promote the growth of fastidious bacteria. Subsequently a group in Helsinki studied the accumulation of polyamines in regenerating rat liver, while Caldarera and his group studied polyamine synthesis in the developing chick embryo. These investigations led to metabolic studies. Ornithine decarboxylase was identified as a key enzyme in polyamine biosynthesis, while polyamine and diamine oxidations were studied by Mondovì. alpha-Diflouromethylornithine (DFMO) was synthesized by Merrell-Dow and became a potent inhibitor of ornithine decarboxylase. The findings of Russell that polyamines are excreted in the urine of cancer patients drew the attention of oncologists, who attempted the use new technologies for the detection of cancer and improving therapy. With the advance of molecular biology the structure of polyamine-biosynthetic enzymes was elaborated. Plants served as another important tool to study the physiological functions of polyamines. Bagni and his group at Bologna were pioneers in that field and for more than forty-six years set the foundation of a most interesting discipline. 2010 Elsevier Masson SAS. All rights reserved.
2013-06-01
data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this...Gaussia luciferase reconstitution, high throughput screen, small molecule inhibitors, human prostate carcinoma cells, pharmacokinetcs, prostate cancer...cells. The increase in ROS levels is probably due to an induction of a polyamine oxidation pathway and specific small molecule inhibitors of this
Fukuchi, Junichi; Hiipakka, Richard A; Kokontis, John M; Nishimura, Kazuhiro; Igarashi, Kazuei; Liao, Shutsung
2004-07-16
Identification of the polyamine transporter gene will be useful for modulating polyamine accumulation in cells and should be a good target for controlling cell proliferation. Polyamine transport activity in mammalian cells is critical for accumulation of the polyamine analog methylglyoxal bis(guanylhydrazone) (MGBG) that induces apoptosis, although a gene responsible for transport activity has not been identified. Using a retroviral gene trap screen, we generated MGBG-resistant Chinese hamster ovary (CHO) cells to identify genes involved in polyamine transport activity. One gene identified by the method encodes TATA-binding protein-associated factor 7 (TAF7), which functions not only as one of the TAFs, but also a coactivator for c-Jun. TAF7-deficient cells had decreased capacity for polyamine uptake (20% of CHO cells), decreased AP-1 activation, as well as resistance to MGBG-induced apoptosis. Stable expression of TAF7 in TAF7-deficient cells restored transport activity (55% of CHO cells), AP-1 gene transactivation (100% of CHO cells), and sensitivity to MGBG-induced apoptosis. Overexpression of TAF7 in CHO cells did not increase transport activity, suggesting that TAF7 may be involved in the maintenance of basal activity. c-Jun NH2-terminal kinase inhibitors blocked MGBG-induced apoptosis without alteration of polyamine transport. Decreased TAF7 expression, by RNA interference, in androgen-independent human prostate cancer LN-CaP104-R1 cells resulted in lower polyamine transport activity (25% of control) and resistance to MGBG-induced growth arrest. Taken together, these results reveal a physiological function of TAF7 as a basal regulator for mammalian polyamine transport activity and MGBG-induced apoptosis.
Huber, M; Pelletier, J G; Torossian, K; Dionne, P; Gamache, I; Charest-Gaudreault, R; Audette, M; Poulin, R
1996-11-01
We have synthesized 2,2'-dithiobis(N-ethyl-spermine-5-carboxamide) (DESC), its thiol monomer (MESC), and the mixed MESC-cysteamine disulfide (DEASC) as potential inhibitors of polyamine transport in mammalian cells. DESC was the most potent antagonist of spermine transport in ZR-75-1 human breast cancer cells, with Ki values of 5. 0 +/- 0.7, 80 +/- 31, and 16 +/- 3 microM for DESC, MESC, and DEASC, respectively. DESC also strongly blocked putrescine and spermidine uptake in ZR-75-1 cells (Ki = 1.6 +/- 0.5 and 2.7 +/- 1.1 microM, respectively). While DESC and MESC were purely competitive inhibitors of putrescine transport, DEASC was a mixed competitive/noncompetitive antagonist. Remarkably, DESC was virtually impermeant in ZR-75-1 cells despite its low Ki toward polyamine transport. The marked difference in affinity between DESC and MESC was essentially due to the tail-to-tail juxtaposition of two spermine-like structures, suggesting that dimeric ligands of the polyamine transporter might simultaneously interact with more than one binding site. While DESC strongly decreased the initial rate of [3H]spermidine transport, even a 40-fold molar excess of antagonist could not completely abolish intracellular spermidine accumulation. Moreover, as little as 0.3 microM spermidine fully restored growth in ZR-75-1 cells treated with an inhibitor of polyamine biosynthesis in the presence of 50 microM DESC, thus emphasizing the importance of uptake of trace amounts of exogenous polyamines. Thus, reducing the exogenous supply of polyamines with a potent competitive inhibitor may be kinetically inadequate to block replenishment of the polyamine pool in polyamine-depleted tumor cells that display high transport capacity. These results demonstrate that polyamine analogues cross-linked into a dimeric structure such as DESC interact with high affinity with the mammalian polyamine carrier without being used as substrates. These novel properties provide a framework for the design of specific irreversible inhibitors of the polyamine transporter, which should present advantages over competitive antagonists for an efficient blockade of polyamine transport in tumor cells.
Rodrigues, A F; Formas-Oliveira, A S; Bandeira, V S; Alves, P M; Hu, W S; Coroadinha, A S
2013-11-01
Biopharmaceuticals derived from enveloped virus comprise an expanding market of vaccines, oncolytic vectors and gene therapy products. Thus, increased attention is given to the development of robust high-titer cell hosts for their manufacture. However, the knowledge on the physiological constraints modulating virus production is still scarce and the use of integrated strategies to improve hosts productivity and upstream bioprocess an under-explored territory. In this work, we conducted a functional genomics study, including the transcriptional profiling and central carbon metabolism analysis, following the metabolic changes in the transition 'parental-to-producer' of two human cell lines producing recombinant retrovirus. Results were gathered into three comprehensive metabolic maps, providing a broad and integrated overview of gene expression changes for both cell lines. Eight pathways were identified to be recruited in the virus production state: amino acid catabolism, carbohydrate catabolism and integration of the energy metabolism, nucleotide metabolism, glutathione metabolism, pentose phosphate pathway, polyamines biosynthesis and lipid metabolism. Their ability to modulate viral titers was experimentally challenged, leading to improved specific productivities of recombinant retrovirus up to 6-fold. Within recruited pathways in the virus production state, we sought for metabolic engineering gene targets in the low producing phenotypes. A mining strategy was used alternative to the traditional approach 'high vs. low producer' clonal comparison. Instead, 'high vs. low producer' from different genetic backgrounds (i.e. cell origins) were compared. Several genes were identified as limiting in the low-production phenotype, including two enzymes from cholesterol biosynthesis, two enzymes from glutathione biosynthesis and the regulatory machinery of polyamines biosynthesis. This is thus a frontier work, bridging fundamentals to technological research and contributing to enlarge our understanding of enveloped virus production dynamics in mammalian cell hosts. © 2013 Published by Elsevier Inc.
Nilam, Mohamed; Gribbon, Philip; Reinshagen, Jeanette; Cordts, Kathrin; Schwedhelm, Edzard; Nau, Werner M; Hennig, Andreas
2017-08-01
Polyamines play an important role in cell growth, differentiation, and cancer development, and the biosynthetic pathway of polyamines is established as a drug target for the treatment of parasitic diseases, neoplasia, and cancer chemoprevention. The key enzyme in polyamine biosynthesis is ornithine decarboxylase (ODC). We report herein an analytical method for the continuous fluorescence monitoring of ODC activity based on the supramolecular receptor cucurbit[6]uril (CB6) and the fluorescent dye trans-4-[4-(dimethylamino)styryl]-1-methylpyridinium iodide (DSMI). CB6 has a significantly higher binding constant to the ODC product putrescine (>10 7 M -1 ) than to the substrate L-ornithine (340 M -1 ). This enables real-time monitoring of the enzymatic reaction through a continuous fluorescence change caused by dye displacement from the macrocycle by the formed product, which allowed a straightforward determination of enzyme kinetic parameters ( k cat = 0.12 s -1 and K M = 24 µM) and inhibition constants of the two ODC inhibitors α-difluoromethylornithine (DFMO) and epigallocatechin gallate (EGCG). The potential for high-throughput screening (HTS) was demonstrated by excellent Z' factors (>0.9) in a microplate reader format, and the sensitivity of the assay is comparable to or better than most established complementary methods, which invariably have the disadvantage of not being compatible with direct implementation and upscaling to HTS format in the drug discovery process.
Putrescine as indicator of manganese neurotoxicity: Dose-response study in human SH-SY5Y cells.
Fernandes, Jolyn; Chandler, Joshua D; Liu, Ken H; Uppal, Karan; Go, Young-Mi; Jones, Dean P
2018-06-01
Disrupted polyamine metabolism with elevated putrescine is associated with neuronal dysfunction. Manganese (Mn) is an essential nutrient that causes neurotoxicity in excess, but methods to evaluate biochemical responses to high Mn are limited. No information is available on dose-response effects of Mn on putrescine abundance and related polyamine metabolism. The present research was to test the hypothesis that Mn causes putrescine accumulation over a physiologically adequate to toxic concentration range in a neuronal cell line. We used human SH-SY5Y neuroblastoma cells treated with MnCl 2 under conditions that resulted in cell death or no cell death after 48 h. Putrescine and other metabolites were analyzed by liquid chromatography-ultra high-resolution mass spectrometry. Putrescine-related pathway changes were identified with metabolome-wide association study (MWAS). Results show that Mn caused a dose-dependent increase in putrescine over a non-toxic to toxic concentration range. MWAS of putrescine showed positive correlations with the polyamine metabolite N8-acetylspermidine, methionine-related precursors, and arginine-associated urea cycle metabolites, while putrescine was negatively correlated with γ-aminobutyric acid (GABA)-related and succinate-related metabolites (P < 0.001, FDR < 0.01). These data suggest that measurement of putrescine and correlated metabolites may be useful to study effects of Mn intake in the high adequate to UL range. Copyright © 2018. Published by Elsevier Ltd.
Relevance of the Axis Spermidine/eIF5A for Plant Growth and Development
Belda-Palazón, Borja; Almendáriz, Carla; Martí, Esmeralda; Carbonell, Juan; Ferrando, Alejandro
2016-01-01
One key role of the essential polyamine spermidine in eukaryotes is to provide the 4-aminobutyl moiety group destined to the post-translational modification of a lysine in the highly conserved translation factor eIF5A. This modification is catalyzed by two sequential enzymatic steps leading to the activation of eIF5A by the conversion of one conserved lysine to the unusual amino acid hypusine. The active translation factor facilitates the sequence-specific translation of polyproline sequences that otherwise cause ribosome stalling. In spite of the well-characterized involvement of active eIF5A in the translation of proline repeat-rich proteins, its biological role has been recently elucidated only in mammals, and it is poorly described at the functional level in plants. Here we describe the alterations in plant growth and development caused by RNAi-mediated conditional genetic inactivation of the hypusination pathway in Arabidopsis thaliana by knocking-down the enzyme deoxyhypusine synthase. We have uncovered that spermidine-mediated activation of eIF5A by hypusination is involved in several aspects of plant biology such as the control of flowering time, the aerial and root architecture, and root hair growth. In addition this pathway is required for adaptation to challenging growth conditions such as high salt and high glucose medium and to elevated concentrations of the plant hormone ABA. We have also performed a bioinformatic analysis of polyproline-rich containing proteins as putative eIF5A targets to uncover their organization in clusters of protein networks to find molecular culprits for the disclosed phenotypes. This study represents a first attempt to provide a holistic view of the biological relevance of the spermidine-dependent hypusination pathway for plant growth and development. PMID:26973686
Pottosin, Igor; Shabala, Sergey
2014-01-01
Polyamines are unique polycationic metabolites, controlling a variety of vital functions in plants, including growth and stress responses. Over the last two decades a bulk of data was accumulated providing explicit evidence that polyamines play an essential role in regulating plant membrane transport. The most straightforward example is a blockage of the two major vacuolar cation channels, namely slow (SV) and fast (FV) activating ones, by the micromolar concentrations of polyamines. This effect is direct and fully reversible, with a potency descending in a sequence Spm(4+) > Spd(3+) > Put(2+). On the contrary, effects of polyamines on the plasma membrane (PM) cation and K(+)-selective channels are hardly dependent on polyamine species, display a relatively low affinity, and are likely to be indirect. Polyamines also affect vacuolar and PM H(+) pumps and Ca(2+) pump of the PM. On the other hand, catabolization of polyamines generates H2O2 and other reactive oxygen species (ROS), including hydroxyl radicals. Export of polyamines to the apoplast and their oxidation there by available amine oxidases results in the induction of a novel ion conductance and confers Ca(2+) influx across the PM. This mechanism, initially established for plant responses to pathogen attack (including a hypersensitive response), has been recently shown to mediate plant responses to a variety of abiotic stresses. In this review we summarize the effects of polyamines and their catabolites on cation transport in plants and discuss the implications of these effects for ion homeostasis, signaling, and plant adaptive responses to environment.
Pottosin, Igor; Shabala, Sergey
2014-01-01
Polyamines are unique polycationic metabolites, controlling a variety of vital functions in plants, including growth and stress responses. Over the last two decades a bulk of data was accumulated providing explicit evidence that polyamines play an essential role in regulating plant membrane transport. The most straightforward example is a blockage of the two major vacuolar cation channels, namely slow (SV) and fast (FV) activating ones, by the micromolar concentrations of polyamines. This effect is direct and fully reversible, with a potency descending in a sequence Spm4+ > Spd3+ > Put2+. On the contrary, effects of polyamines on the plasma membrane (PM) cation and K+-selective channels are hardly dependent on polyamine species, display a relatively low affinity, and are likely to be indirect. Polyamines also affect vacuolar and PM H+ pumps and Ca2+ pump of the PM. On the other hand, catabolization of polyamines generates H2O2 and other reactive oxygen species (ROS), including hydroxyl radicals. Export of polyamines to the apoplast and their oxidation there by available amine oxidases results in the induction of a novel ion conductance and confers Ca2+ influx across the PM. This mechanism, initially established for plant responses to pathogen attack (including a hypersensitive response), has been recently shown to mediate plant responses to a variety of abiotic stresses. In this review we summarize the effects of polyamines and their catabolites on cation transport in plants and discuss the implications of these effects for ion homeostasis, signaling, and plant adaptive responses to environment. PMID:24795739
Geddes, Ryan D.; Wang, Xuan; Yomano, Lorraine P.; Miller, Elliot N.; Zheng, Huabao; Shanmugam, Keelnatham T.
2014-01-01
Expression of genes encoding polyamine transporters from plasmids and polyamine supplements increased furfural tolerance (growth and ethanol production) in ethanologenic Escherichia coli LY180 (in AM1 mineral salts medium containing xylose). This represents a new approach to increase furfural tolerance and may be useful for other organisms. Microarray comparisons of two furfural-resistant mutants (EMFR9 and EMFR35) provided initial evidence for the importance of polyamine transporters. Each mutant contained a single polyamine transporter gene that was upregulated over 100-fold (microarrays) compared to that in the parent LY180, as well as a mutation that silenced the expression of yqhD. Based on these genetic changes, furfural tolerance was substantially reconstructed in the parent, LY180. Deletion of potE in EMFR9 lowered furfural tolerance to that of the parent. Deletion of potE and puuP in LY180 also decreased furfural tolerance, indicating functional importance of the native genes. Of the 8 polyamine transporters (18 genes) cloned and tested, half were beneficial for furfural tolerance (PotE, PuuP, PlaP, and PotABCD). Supplementing AM1 mineral salts medium with individual polyamines (agmatine, putrescine, and cadaverine) also increased furfural tolerance but to a smaller extent. In pH-controlled fermentations, polyamine transporter plasmids were shown to promote the metabolism of furfural and substantially reduce the time required to complete xylose fermentation. This increase in furfural tolerance is proposed to result from polyamine binding to negatively charged cellular constituents such as nucleic acids and phospholipids, providing protection from damage by furfural. PMID:25063650
Ionotropic Chemosensory Receptors Mediate the Taste and Smell of Polyamines.
Hussain, Ashiq; Zhang, Mo; Üçpunar, Habibe K; Svensson, Thomas; Quillery, Elsa; Gompel, Nicolas; Ignell, Rickard; Grunwald Kadow, Ilona C
2016-05-01
The ability to find and consume nutrient-rich diets for successful reproduction and survival is fundamental to animal life. Among the nutrients important for all animals are polyamines, a class of pungent smelling compounds required in numerous cellular and organismic processes. Polyamine deficiency or excess has detrimental effects on health, cognitive function, reproduction, and lifespan. Here, we show that a diet high in polyamine is beneficial and increases reproductive success of flies, and we unravel the sensory mechanisms that attract Drosophila to polyamine-rich food and egg-laying substrates. Using a combination of behavioral genetics and in vivo calcium imaging, we demonstrate that Drosophila uses multisensory detection to find and evaluate polyamines present in overripe and fermenting fruit, their favored feeding and egg-laying substrate. In the olfactory system, two coexpressed ionotropic receptors (IRs), IR76b and IR41a, mediate the long-range attraction to the odor. In the gustatory system, multimodal taste sensation by IR76b receptor and GR66a bitter receptor neurons is used to evaluate quality and valence of the polyamine providing a mechanism for the fly's high attraction to polyamine-rich and sweet decaying fruit. Given their universal and highly conserved biological roles, we propose that the ability to evaluate food for polyamine content may impact health and reproductive success also of other animals including humans.
Ionotropic Chemosensory Receptors Mediate the Taste and Smell of Polyamines
Üçpunar, Habibe K.; Svensson, Thomas; Quillery, Elsa; Gompel, Nicolas; Ignell, Rickard; Grunwald Kadow, Ilona C.
2016-01-01
The ability to find and consume nutrient-rich diets for successful reproduction and survival is fundamental to animal life. Among the nutrients important for all animals are polyamines, a class of pungent smelling compounds required in numerous cellular and organismic processes. Polyamine deficiency or excess has detrimental effects on health, cognitive function, reproduction, and lifespan. Here, we show that a diet high in polyamine is beneficial and increases reproductive success of flies, and we unravel the sensory mechanisms that attract Drosophila to polyamine-rich food and egg-laying substrates. Using a combination of behavioral genetics and in vivo calcium imaging, we demonstrate that Drosophila uses multisensory detection to find and evaluate polyamines present in overripe and fermenting fruit, their favored feeding and egg-laying substrate. In the olfactory system, two coexpressed ionotropic receptors (IRs), IR76b and IR41a, mediate the long-range attraction to the odor. In the gustatory system, multimodal taste sensation by IR76b receptor and GR66a bitter receptor neurons is used to evaluate quality and valence of the polyamine providing a mechanism for the fly’s high attraction to polyamine-rich and sweet decaying fruit. Given their universal and highly conserved biological roles, we propose that the ability to evaluate food for polyamine content may impact health and reproductive success also of other animals including humans. PMID:27145030
Hou, Ming-Hon; Lu, Wen-Je; Huang, Chun-Yu; Fan, Ruey-Jane; Yuann, Jeu-Ming P
2009-06-09
Few studies have examined the effects of polyamines on the action of DNA-binding anticancer drugs. Here, a Co(II)-mediated dimeric mithramycin (Mith) complex, (Mith)(2)-Co(II), was shown to be resistant to polyamine competition toward the divalent metal ion when compared to the Fe(II)-mediated drug complexes. Surface plasmon resonance experiments demonstrated that polyamines interfered with the binding capacity and association rates of (Mith)(2)-Co(II) binding to DNA duplexes, while the dissociation rates were not affected. Although (Mith)(2)-Co(II) exhibited the highest oxidative activity under physiological conditions (pH 7.3 and 37 degrees C), polyamines (spermine in particular) inhibited the DNA cleavage activity of the (Mith)(2)-Co(II) in a concentration-dependent manner. Depletion of intracellular polyamines by methylglyoxal bis(guanylhydrazone) (MGBG) enhanced the sensitivity of A549 lung cancer cells to (Mith)(2)-Co(II), most likely due to the decreased intracellular effect of polyamines on the action of (Mith)(2)-Co(II). Our study suggests a novel method for enhancing the anticancer activity of DNA-binding metalloantibiotics through polyamine depletion.
Polyamine-Induced Rapid Root Abscission in Azolla pinnata
Gurung, Sushma; Cohen, Michael F.; Fukuto, Jon; Yamasaki, Hideo
2012-01-01
Floating ferns of the genus Azolla detach their roots under stress conditions, a unique adaptive response termed rapid root abscission. We found that Azolla pinnata plants exhibited dose-dependent rapid root abscission in response to the polyamines spermidine and spermine after a substantial time lag (>20 min). The duration of the time lag decreased in response to high pH and high temperature whereas high light intensity increased the time lag and markedly lowered the rate of abscission. The oxidation products of polyamines, 1,3-diaminopropane, β-alanine and hydrogen peroxide all failed to initiate root abscission, and hydroxyethyl hydrazine, an inhibitor of polyamine oxidase, did not inhibit spermine-induced root abscission. Exposure of A. pinnata to the polyamines did not result in detectable release of NO and did not affect nitrite-dependent NO production. The finding of polyamine-induced rapid root abscission provides a facile assay for further study of the mode of action of polyamines in plant stress responses. PMID:22997568
Polyamine-Induced Rapid Root Abscission in Azolla pinnata.
Gurung, Sushma; Cohen, Michael F; Fukuto, Jon; Yamasaki, Hideo
2012-01-01
Floating ferns of the genus Azolla detach their roots under stress conditions, a unique adaptive response termed rapid root abscission. We found that Azolla pinnata plants exhibited dose-dependent rapid root abscission in response to the polyamines spermidine and spermine after a substantial time lag (>20 min). The duration of the time lag decreased in response to high pH and high temperature whereas high light intensity increased the time lag and markedly lowered the rate of abscission. The oxidation products of polyamines, 1,3-diaminopropane, β-alanine and hydrogen peroxide all failed to initiate root abscission, and hydroxyethyl hydrazine, an inhibitor of polyamine oxidase, did not inhibit spermine-induced root abscission. Exposure of A. pinnata to the polyamines did not result in detectable release of NO and did not affect nitrite-dependent NO production. The finding of polyamine-induced rapid root abscission provides a facile assay for further study of the mode of action of polyamines in plant stress responses.
Code of Federal Regulations, 2012 CFR
2012-01-01
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2013-01-01
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2014-01-01
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2011-01-01
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Kainate receptor pore‐forming and auxiliary subunits regulate channel block by a novel mechanism
Brown, Patricia M. G. E.; Aurousseau, Mark R. P.; Musgaard, Maria; Biggin, Philip C.
2016-01-01
Key points Kainate receptor heteromerization and auxiliary subunits, Neto1 and Neto2, attenuate polyamine ion‐channel block by facilitating blocker permeation.Relief of polyamine block in GluK2/GluK5 heteromers results from a key proline residue that produces architectural changes in the channel pore α‐helical region.Auxiliary subunits exert an additive effect to heteromerization, and thus relief of polyamine block is due to a different mechanism.Our findings have broad implications for work on polyamine block of other cation‐selective ion channels. Abstract Channel block and permeation by cytoplasmic polyamines is a common feature of many cation‐selective ion channels. Although the channel block mechanism has been studied extensively, polyamine permeation has been considered less significant as it occurs at extreme positive membrane potentials. Here, we show that kainate receptor (KAR) heteromerization and association with auxiliary proteins, Neto1 and Neto2, attenuate polyamine block by enhancing blocker permeation. Consequently, polyamine permeation and unblock occur at more negative and physiologically relevant membrane potentials. In GluK2/GluK5 heteromers, enhanced permeation is due to a single proline residue in GluK5 that alters the dynamics of the α‐helical region of the selectivity filter. The effect of auxiliary proteins is additive, and therefore the structural basis of polyamine permeation and unblock is through a different mechanism. As native receptors are thought to assemble as heteromers in complex with auxiliary proteins, our data identify an unappreciated impact of polyamine permeation in shaping the signalling properties of neuronal KARs and point to a structural mechanism that may be shared amongst other cation‐selective ion channels. PMID:26682513
Geddes, Ryan D; Wang, Xuan; Yomano, Lorraine P; Miller, Elliot N; Zheng, Huabao; Shanmugam, Keelnatham T; Ingram, Lonnie O
2014-10-01
Expression of genes encoding polyamine transporters from plasmids and polyamine supplements increased furfural tolerance (growth and ethanol production) in ethanologenic Escherichia coli LY180 (in AM1 mineral salts medium containing xylose). This represents a new approach to increase furfural tolerance and may be useful for other organisms. Microarray comparisons of two furfural-resistant mutants (EMFR9 and EMFR35) provided initial evidence for the importance of polyamine transporters. Each mutant contained a single polyamine transporter gene that was upregulated over 100-fold (microarrays) compared to that in the parent LY180, as well as a mutation that silenced the expression of yqhD. Based on these genetic changes, furfural tolerance was substantially reconstructed in the parent, LY180. Deletion of potE in EMFR9 lowered furfural tolerance to that of the parent. Deletion of potE and puuP in LY180 also decreased furfural tolerance, indicating functional importance of the native genes. Of the 8 polyamine transporters (18 genes) cloned and tested, half were beneficial for furfural tolerance (PotE, PuuP, PlaP, and PotABCD). Supplementing AM1 mineral salts medium with individual polyamines (agmatine, putrescine, and cadaverine) also increased furfural tolerance but to a smaller extent. In pH-controlled fermentations, polyamine transporter plasmids were shown to promote the metabolism of furfural and substantially reduce the time required to complete xylose fermentation. This increase in furfural tolerance is proposed to result from polyamine binding to negatively charged cellular constituents such as nucleic acids and phospholipids, providing protection from damage by furfural. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Corella, D; Guillén, M; Hernández, J M; Hernández-Yago, J
1998-01-01
Biogenic polyamines have important regulatory functions in various biological processes and it has also been suggested that they could modulate intracellular protein degradation. For an overall assessment of the role of polyamines in this process, we have investigated the effect that the decrease in intracellular polyamine levels caused by inhibitors of polyamine biosynthesis brings about on the degradation of the pools of short- and long-lived proteins in cultured L-132 human lung cells. Treatment of cells with 100 microM (2R,5R)-delta-methyl acetylenic putrescine (MAP), a potent enzyme-activated irreversible inhibitor of ornithine decarboxylase, or with 100 microM MAP plus 50 microM N-butyl 1,3-diaminopropane, a specific inhibitor of spermine synthase, caused a similar decrease (65-70% of control) in the total intracellular levels of polyamines, although they affected the concentrations of spermidine and spermine differently. The effect of the two treatments on protein degradation was essentially the same. In polyamine-depleted cells we observed an inhibition of degradation in long-lived proteins of 16% (P<0.05), with a significant increase in the half-life (t12) of this pool from 100.5 to 120.1 h. This was concomitant with an increase of 26% (P<0. 05) in degradation in short-lived proteins, with a significant decrease in the t12 of this pool from 0.85 to 0.67 h. Recovery of polyamine levels by the addition of 50 microM spermidine to polyamine-depleted cells resulted in a restoration of the degradation rates in both pools of proteins. The way(s) by which polyamines could modulate proteolysis are discussed. PMID:9716494
Ochocki, Joshua D; Khare, Sanika; Hess, Markus; Ackerman, Daniel; Qiu, Bo; Daisak, Jennie I; Worth, Andrew J; Lin, Nan; Lee, Pearl; Xie, Hong; Li, Bo; Wubbenhorst, Bradley; Maguire, Tobi G; Nathanson, Katherine L; Alwine, James C; Blair, Ian A; Nissim, Itzhak; Keith, Brian; Simon, M Celeste
2018-05-04
Kidney cancer, one of the ten most prevalent malignancies in the world, has exhibited increased incidence over the last decade. The most common subtype is "clear cell" renal cell carcinoma (ccRCC), which features consistent metabolic abnormalities, such as highly elevated glycogen and lipid deposition. By integrating metabolomics, genomic, and transcriptomic data, we determined that enzymes in multiple metabolic pathways are universally depleted in human ccRCC tumors, which are otherwise genetically heterogeneous. Notably, the expression of key urea cycle enzymes, including arginase 2 (ARG2) and argininosuccinate synthase 1 (ASS1), is strongly repressed in ccRCC. Reduced ARG2 activity promotes ccRCC tumor growth through at least two distinct mechanisms: conserving the critical biosynthetic cofactor pyridoxal phosphate and avoiding toxic polyamine accumulation. Pharmacological approaches to restore urea cycle enzyme expression would greatly expand treatment strategies for ccRCC patients, where current therapies only benefit a subset of those afflicted with renal cancer. Copyright © 2018 Elsevier Inc. All rights reserved.
Arginaseless Neurospora: Genetics, Physiology, and Polyamine Synthesis
Davis, Rowland H.; Lawless, Mary B.; Port, Loretta A.
1970-01-01
Four arginaseless mutants of Neurospora crassa have been isolated. All carry mutations which lie at a single locus, aga, on linkage group VIIR. A study of aga strains shows the arginase reaction to be the major, perhaps the only, route of arginine consumption in Neurospora other than protein synthesis. Ornithine-δ-transaminase, the second enzyme of the arginine catabolic pathway, is present and normally inducible by arginine in aga strains, and ornithine transcarbamylase, an enzyme of arginine synthesis, also has normal activity. Arginine inhibits the growth of aga strains. The inhibition can be reversed by spermidine, putrescine (1,4-diaminobutane), or ornithine. The results suggest that ornithine is the major source of the putrescine moiety of polyamines in Neurospora, and that putrescine is an essential growth factor for this organism. The inhibition of aga strains by arginine can be attributed to feedback inhibition of ornithine synthesis by arginine, combined with the complete lack of ornithine normally provided by the arginase reaction. PMID:5419257
Effect of hindlimb suspension and clenbuterol treatment on polyamine levels in skeletal muscle
NASA Technical Reports Server (NTRS)
Abukhalaf, Imad K.; von Deutsch, Daniel A.; Wineski, Lawrence E.; Silvestrov, Natalia A.; Abera, Saare A.; Sahlu, Sinafikish W.; Potter, David E.; Thierry-Palmer, M. (Principal Investigator)
2002-01-01
Polyamines are unbiquitous, naturally occurring small aliphatic, polycationic, endogenous compounds. They are involved in many cellular processes and may serve as secondary or tertiary messengers to hormonal regulation. The relationship of polyamines and skeletal muscle mass of adductor longus, extensor digitorum longus, and gastrocnemius under unloading (hindlimb suspension) conditions was investigated. Unloading significantly affected skeletal muscle polyamine levels in a fiber-type-specific fashion. Under loading conditions, clenbuterol treatment increased all polyamine levels, whereas under unloading conditions, only the spermidine levels were consistently increased. Unloading attenuated the anabolic effects of clenbuterol in predominately slow-twitch muscles (adductor longus), but had little impact on clenbuterol's action as a countermeasure in fast- twitch muscles such as the extensor digitorum longus. Spermidine appeared to be the primary polyamine involved in skeletal muscle atrophy/hypertrophy. Copyright 2002 S. Karger AG, Basel.
The Aromatic Head Group of Spider Toxin Polyamines Influences Toxicity to Cancer Cells
Wilson, David; McIntyre, Lachlan; Smith, Jennifer J.; Tribolet, Leon; Loukas, Alex; Liddell, Michael J.; Daly, Norelle L.
2017-01-01
Spider venoms constitute incredibly diverse libraries of compounds, many of which are involved in prey capture and defence. Polyamines are often prevalent in the venom and target ionotropic glutamate receptors. Here we show that a novel spider polyamine, PA366, containing a hydroxyphenyl-based structure is present in the venom of several species of tarantula, and has selective toxicity against MCF-7 breast cancer cells. By contrast, a polyamine from an Australian funnel-web spider venom, which contains an identical polyamine tail to PA366 but an indole-based head-group, is only cytotoxic at high concentrations. Our results suggest that the ring structure plays a role in the cytotoxicity and that modification to the polyamine head group might lead to more potent and selective compounds with potential as novel cancer treatments. PMID:29077051
The Aromatic Head Group of Spider Toxin Polyamines Influences Toxicity to Cancer Cells.
Wilson, David; Boyle, Glen M; McIntyre, Lachlan; Nolan, Matthew J; Parsons, Peter G; Smith, Jennifer J; Tribolet, Leon; Loukas, Alex; Liddell, Michael J; Rash, Lachlan D; Daly, Norelle L
2017-10-27
Spider venoms constitute incredibly diverse libraries of compounds, many of which are involved in prey capture and defence. Polyamines are often prevalent in the venom and target ionotropic glutamate receptors. Here we show that a novel spider polyamine, PA 366 , containing a hydroxyphenyl-based structure is present in the venom of several species of tarantula, and has selective toxicity against MCF-7 breast cancer cells. By contrast, a polyamine from an Australian funnel-web spider venom, which contains an identical polyamine tail to PA 366 but an indole-based head-group, is only cytotoxic at high concentrations. Our results suggest that the ring structure plays a role in the cytotoxicity and that modification to the polyamine head group might lead to more potent and selective compounds with potential as novel cancer treatments.
Polyamine catabolism and disease
CASERO, Robert A.; PEGG, Anthony E.
2009-01-01
In addition to polyamine homeostasis, it has become increasingly clear that polyamine catabolism can play a dominant role in drug response, apoptosis, response to stressful stimuli, and contribute to the etiology of several pathological states, including cancer. The highly inducible enzymes spermidine/spermine N1-acetyltransferase (SSAT) and spermine oxidase (SMO), and, the generally constitutively expressed N1-acetylpolyamine oxidase (APAO), appear to play critical roles in many normal and disease processes. The dysregulation of polyamine catabolism frequently accompanies several disease states and suggests that such dysregulation may both provide useful insight into disease mechanism and provide unique drugable targets that can be exploited for therapeutic benefit. Each of these enzymes has the potential to alter polyamine homeostasis in response to multiple cell signals and the two oxidases produce the reactive oxygen species H2O2 and aldehydes, each with the potential to produce pathologies. The activity of SSAT has the potential to provide substrates for APAO or substrates for the polyamine exporter, thus reducing the intracellular polyamine concentration, the net effect of which depends on the magnitude and rate of any increase in SSAT. SSAT may also influence cellular metabolism via interaction with other proteins and by perturbing the content of acetyl CoA and ATP. The goal of this review is to cover those aspects of polyamine catabolism that have potential to impact disease etiology or treatment and to provide a solid background in this ever more exciting aspect of polyamine biology. PMID:19589128
Food Polyamine and Cardiovascular Disease -An Epidemiological Study-
Soda, Kuniyasu; Kano, Yoshihiko; Chiba, Fumihiro
2012-01-01
The purpose of this study was to examine the contribution of dietary polyamines toward preventing cardiovascular disease (CVD). Age-standardized mortality rates as well as other relevant information regarding individuals with CVD were gathered from the World Health Organization and the International Monetary Fund in 48 different European and other Western countries. Food supply data were collected from the database of the United Nations, and the amount of dietary polyamines was estimated by using polyamine concentrations in foods from published sources. The association between CVD mortality and the amount of polyamines was investigated by performing a series of multiple linear regression analyses. Analyses using factors known to modulate the risk of CVD including: Gross Domestic Product (GDP) (standardized regression coefficient (r) = -0.786, p < 0.001) and the amount of fruits, vegetable, nuts, and beans (r = -0.183, p = 0.001) but not including polyamines, showed negative associations with CVD, while smoking rate (r = 0.139, p = 0.041) and whole milk amount (r = 0.131, p = 0.028) showed positive associations with CVD. When the amount of polyamines was added to the analyses as a covariate, GDP (r = -0.864, p < 0.001) and polyamines (r = -0.355, p = 0.007) showed negative associations with CVD, while smoking rate (r = 0.183, p = 0.006) and whole milk (r = 0.113, p = 0.041) showed positive associations with CVD. The inverse association between dietary polyamines and CVD mortality revealed by the present study merits further evaluation. PMID:23121753
Food polyamine and cardiovascular disease--an epidemiological study.
Soda, Kuniyasu; Kano, Yoshihiko; Chiba, Fumihiro
2012-09-28
The purpose of this study was to examine the contribution of dietary polyamines toward preventing cardiovascular disease (CVD). Age-standardized mortality rates as well as other relevant information regarding individuals with CVD were gathered from the World Health Organization and the International Monetary Fund in 48 different European and other Western countries. Food supply data were collected from the database of the United Nations, and the amount of dietary polyamines was estimated by using polyamine concentrations in foods from published sources. The association between CVD mortality and the amount of polyamines was investigated by performing a series of multiple linear regression analyses. Analyses using factors known to modulate the risk of CVD including: Gross Domestic Product (GDP) (standardized regression coefficient (r) = -0.786, p < 0.001) and the amount of fruits, vegetable, nuts, and beans (r = -0.183, p = 0.001) but not including polyamines, showed negative associations with CVD, while smoking rate (r = 0.139, p = 0.041) and whole milk amount (r = 0.131, p = 0.028) showed positive associations with CVD. When the amount of polyamines was added to the analyses as a covariate, GDP (r = -0.864, p < 0.001) and polyamines (r = -0.355, p = 0.007) showed negative associations with CVD, while smoking rate (r = 0.183, p = 0.006) and whole milk (r = 0.113, p = 0.041) showed positive associations with CVD. The inverse association between dietary polyamines and CVD mortality revealed by the present study merits further evaluation.
Eloranta, Terho O.; Raina, Aarne M.
1977-01-01
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 affected S-adenosylmethionine metabolism. The ratio of spermidine/spermine decreased markedly, but the concentration of total polyamines did not change significantly. The activity of S-adenosylmethionine decarboxylase initially decreased and then increased during prolonged starvation. This increase was dependent on intact adrenals. Re-feeding of starved animals caused a rapid but transient stimulation of polyamine synthesis and also increased the concentrations of S-adenosylmethionine and S-adenosylhomocysteine. Similarly, cortisol treatment enhanced the synthesis of polyamines, S-adenosylmethionine and S-adenosylhomocysteine. Feeding with a methionine-deficient diet for 7–14 days profoundly increased the concentration of spermidine, whereas the concentrations of total polyamines and of S-adenosylmethionine showed no significant changes. The results show that nutritional state and adrenal function play a significant role in the regulation of hepatic metabolism of S-adenosylmethionine and polyamines. They further indicate that under a variety of physiological and experimental conditions the concentrations of S-adenosylmethionine and of total polyamines remain fairly constant and that changes in polyamine metabolism are not primarily connected with changes in the accumulation of S-adenosylmethionine or S-adenosylhomocysteine. PMID:597268
Rastogi, Rajeev; Sawhney, Vipen K.
1990-01-01
The floral organs of the male sterile stamenless-2 (sl-2/sl-2) mutant of tomato (Lycopersicon esculentum Mill.) contain significantly higher level of polyamines than those of the normal (R Rastogi, VK Sawhney [1990] Plant Physiol 93: 439-445). The effects of putrescine, spermidine and spermine, and three different inhibitors of polyamine biosynthesis on the in vitro development of floral buds of the normal and sl-2/sl-2 mutant were studied. The polyamines were inhibitory to the in vitro growth and development of both the normal and mutant floral buds and they induced abnormal stamen development in normal flowers. The inhibitors of polyamine biosynthesis also inhibited the growth and development of floral organs of the two genotypes, but the normal flowers showed greater sensitivity than the mutant. The inhibitors also promoted the formation of normal-looking pollen in stamens of some mutant flowers. The effect of the inhibitors on polyamine levels was not determined. The polyamine-induced abnormal stamen development in the normal, and the inhibitor-induced production of normal-looking pollen in mutant flowers support the suggestion that the elevated polyamine levels contribute to abnormal stamen development in the sl-2/sl-2 mutant of tomato. Images Figure 3 Figure 5 PMID:16667486
Polyamine biosynthesis is critical for growth and differentiation of the pancreas
Mastracci, Teresa L.; Robertson, Morgan A.; Mirmira, Raghavendra G.; Anderson, Ryan M.
2015-01-01
The pancreas, in most studied vertebrates, is a compound organ with both exocrine and endocrine functions. The exocrine compartment makes and secretes digestive enzymes, while the endocrine compartment, organized into islets of Langerhans, produces hormones that regulate blood glucose. High concentrations of polyamines, which are aliphatic amines, are reported in exocrine and endocrine cells, with insulin-producing β cells showing the highest concentrations. We utilized zebrafish as a model organism, together with pharmacological inhibition or genetic manipulation, to determine how polyamine biosynthesis functions in pancreatic organogenesis. We identified that inhibition of polyamine biosynthesis reduces exocrine pancreas and β cell mass, and that these reductions are at the level of differentiation. Moreover, we demonstrate that inhibition of ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis, phenocopies inhibition or knockdown of the enzyme deoxyhypusine synthase (DHS). These data identify that the pancreatic requirement for polyamine biosynthesis is largely mediated through a requirement for spermidine for the downstream posttranslational modification of eIF5A by its enzymatic activator DHS, which in turn impacts mRNA translation. Altogether, we have uncovered a role for polyamine biosynthesis in pancreatic organogenesis and identified that it may be possible to exploit polyamine biosynthesis to manipulate pancreatic cell differentiation. PMID:26299433
Chaturvedi, Rupesh; Asim, Mohammad; Barry, Daniel P; Frye, Jeanetta W; Casero, Robert A; Wilson, Keith T
2014-03-01
The gastric pathogen Helicobacter pylori causes peptic ulcer disease and gastric cancer. We have reported that in H. pylori-activated macrophages, nitric oxide (NO) derived from inducible NO synthase (iNOS) can kill the bacterium, iNOS protein expression is dependent on uptake of its substrate L-arginine (L-Arg), the polyamine spermine can inhibit iNOS translation by inhibiting L-Arg uptake, and inhibition of polyamine synthesis enhances NO-mediated bacterial killing. Because spermine oxidase (SMO), which back-converts spermine to spermidine, is induced in macrophages by H. pylori, we determined its role in iNOS-dependent host defense. SMO shRNA knockdown in RAW 264.7 murine macrophages resulted in a marked decrease in H. pylori-stimulated iNOS protein, but not mRNA expression, and a 90% reduction in NO levels; NO production was also inhibited in primary murine peritoneal macrophages with SMO knockdown. There was an increase in spermine levels after H. pylori stimulation that rapidly decreased, while SMO knockdown caused a greater increase in spermine that was sustained. With SMO knockdown, L-Arg uptake and killing of H. pylori by macrophages was prevented. The overexpression of SMO by transfection of an expression plasmid prevented the H. pylori-stimulated increase in spermine levels, and led to increased L-Arg uptake, iNOS protein expression and NO production, and H. pylori killing. In two human monocytic cell lines, U937 and THP-1, overexpression of SMO caused a significant enhancement of NO production with H. pylori stimulation. By depleting spermine, SMO can abrogate the inhibitory effect of polyamines on innate immune responses to H. pylori by enhancing antimicrobial NO production.
NASA Astrophysics Data System (ADS)
Bertoluzza, Alessandro; Bonora, S.; Fini, G.; Morelli, M. A.
1993-06-01
Polyamines do not interact with neutral phospholipids (phosphatidylcholines) but they do interact in the presence of bivalent and trivalent cations. The effect of polyvalent cations is explained in terms of dehydration of the bilayer surface. Polyamines interact strongly with negatively charged phospholipids; the presence of bivalent and trivalent cations do not change sensitively the type of interaction between polyamines and phosphatidic acids.
Chattopadhyay, Manas K; Tabor, Celia White; Tabor, Herbert
2009-09-01
A strain of Escherichia coli was constructed in which all of the genes involved in polyamine biosynthesis--speA (arginine decarboxylase), speB (agmatine ureohydrolase), speC (ornithine decarboxylase), spe D (adenosylmethionine decarboxylase), speE (spermidine synthase), speF (inducible ornithine decarboxylase), cadA (lysine decarboxylase), and ldcC (lysine decarboxylase)--had been deleted. Despite the complete absence of all of the polyamines, the strain grew indefinitely in air in amine-free medium, albeit at a slightly (ca. 40 to 50%) reduced growth rate. Even though this strain grew well in the absence of the amines in air, it was still sensitive to oxygen stress in the absence of added spermidine. In contrast to the ability to grow in air in the absence of polyamines, this strain, surprisingly, showed a requirement for polyamines for growth under strictly anaerobic conditions.
Polyamines are Inhibitors of Gastric Acid Secretion
NASA Astrophysics Data System (ADS)
Ray, Tushar K.; Nandi, Jyotirmoy; Pidhorodeckyj, Nykolai; Meng-Ai, Zhou
1982-03-01
The naturally occurring organic polycations such as spermine and spermidine inhibit histamine-stimulated gastric acid secretion by bullfrog gastric mucosa in vitro; spermine is much more potent than spermidine. Unlike the H2 receptor antagonists, the polyamines are completely ineffective from the nutrient side and are effective only from the secretory side of the chambered mucosa. The polyamine effects could be reversed by increasing K+ concentration in the secretory solution. Studies with isolated gastric microsomal vesicles demonstrate that the polyamines do not inhibit the gastric H+,K+-ATPase but greatly decrease the ATPase-mediated uptake of H+ under appropriate conditions. For the latter effects the presence of polyamine within the vesicle interior was found to be essential. Our data strongly suggest an uncoupling of the gastric H+,K+-ATPase system by the polyamines. The therapeutic potential of these and similar compounds in the treatment of hyperacidity and peptic ulcer is discussed.
NASA Technical Reports Server (NTRS)
Henley, C.; Igarashi, M.
1993-01-01
Polyamine synthesis increases in response to injurious stimuli including axotomy and denervation. Reduced eye nystagmus and head-deviation have been observed in unilateral labyrinthectomized (UL) guinea pigs treated with an inhibitor of polyamine synthesis, alpha-difluoromethylornithine (DFMO). We quantified polyamines in the lateral vestibular nuclei (LVN) of control and UL squirrel monkeys during the phase of vestibular compensation (VC) and performed an experiment to determine if DFMO reduces nystagmus previously observed in the guinea pig. Polyamines were detected in the LVN of control and UL squirrel monkeys. Putrescine and spermidine increased in the ipsilateral LVN 3 days after UL with no change in the contralateral LVN. No left-right differences were noted in the 5-day post-UL monkey. DFMO reduced nystagmus in a UL squirrel monkey. These findings suggest that polyamines are important in vestibular function and may contribute to nystagmus observed in VC.
Phase-change related epigenetic and physiological changes in Pinus radiata D. Don.
Fraga, Mario F; Cañal, Maria Jesús; Rodríguez, Roberto
2002-08-01
DNA methylation and polyamine levels were analysed before and after Pinus radiata D. Don. phase change in order to identify possible molecular and physiological phase markers. Juvenile individuals (without reproductive ability) were characterised by a degree of DNA methylation of 30-35% and a ratio of free polyamines to perchloric acid-soluble polyamine conjugates greater than 1, while mature trees (with reproductive ability) had 60% 5-methylcytosine and a ratio of free polyamines to perchloric acid-soluble polyamine conjugates of less than 1. Results obtained with trees that attained reproductive capacity during the experimental period confirmed that changes in the degree of DNA methylation and polyamine concentrations found among juvenile and mature states come about immediately after the phase change. We suggest that both indicators may be associated with the loss of morphogenic ability during ageing, particularly after phase change, through a number of molecular interactions, which are subsequently discussed.
Adachi, Mariya S.; Taylor, Alexander B.; Hart, P. John; Fitzpatrick, Paul F.
2012-01-01
The flavoprotein Fms1 from Saccharomyces cerevisiae catalyzes the oxidation of spermine in the biosynthetic pathway for pantothenic acid. The same reaction is catalyzed by the mammalian polyamine and spermine oxidases. The active site of Fms1 contains three amino acid residues positioned to interact with the polyamine substrate, His67, Asn195, and Asp94. These three residues form a hydrogen-bonding triad with Asn195 the central residue. Previous studies of the effects of mutating His67 are consistent with that residue being important both for interacting with the substrate and for maintaining the hydrogen bonds in the triad (Adachi, M. S., Taylor, A. B., Hart, P. J., and Fitzpatrick, P. F. (2012) Biochemistry 51, 4888-4897). The N195A and D94N enzymes have now been characterized to evaluate their roles in catalysis. Both mutations primarily affect the reductive half-reaction. With N1-acetylspermine as substrate, the rate constant for flavin reduction decreases ~450-fold for both mutations; the effects with spermine as substrate are smaller, 20- to 40-fold. The kcat/Kamine and kcat pH profiles with N1acetylspermine are only slightly changed from the profiles for the wild-type enzyme, consistent with the pKa values arising from the amine substrate or product and not from active site residues. The structure of the N195A enzyme was determined at a resolution of 2.0 Å. The structure shows a molecule of tetraethylene glycol in the active site and establishes that the mutation has no effect on the protein structure. Overall, the results are consistent with the role of Asn195 and Asp94 being to properly position the polyamine substrate for oxidation. PMID:23034052
Adachi, Mariya S; Taylor, Alexander B; Hart, P John; Fitzpatrick, Paul F
2012-10-30
Flavoprotein Fms1 from Saccharomyces cerevisiae catalyzes the oxidation of spermine in the biosynthetic pathway for pantothenic acid. The same reaction is catalyzed by the mammalian polyamine and spermine oxidases. The active site of Fms1 contains three amino acid residues positioned to interact with the polyamine substrate, His67, Asn195, and Asp94. These three residues form a hydrogen-bonding triad with Asn195 being the central residue. Previous studies of the effects of mutating His67 are consistent with that residue being important both for interacting with the substrate and for maintaining the hydrogen bonds in the triad [Adachi, M. S., Taylor, A. B., Hart, P. J., and Fitzpatrick, P. F. (2012) Biochemistry 51, 4888-4897]. The N195A and D94N enzymes have now been characterized to evaluate their roles in catalysis. Both mutations primarily affect the reductive half-reaction. With N(1)-acetylspermine as the substrate, the rate constant for flavin reduction decreases ~450-fold for both mutations; the effects with spermine as the substrate are smaller, 20-40-fold. The k(cat)/K(amine)- and k(cat)-pH profiles with N(1)-acetylspermine are only slightly changed from the profiles for the wild-type enzyme, consistent with the pK(a) values arising from the amine substrate or product and not from active site residues. The structure of the N195A enzyme was determined at a resolution of 2.0 Å. The structure shows a molecule of tetraethylene glycol in the active site and establishes that the mutation has no effect on the protein structure. Overall, the results are consistent with the role of Asn195 and Asp94 being to properly position the polyamine substrate for oxidation.
Li, Bin; Kim, Sok Ho; Zhang, Yang; Hanfrey, Colin C; Elliott, Katherine A; Ealick, Steven E; Michael, Anthony J
2015-09-01
The polyamine spermidine is absolutely required for growth and cell proliferation in eukaryotes, due to its role in post-translational modification of essential translation elongation factor eIF5A, mediated by deoxyhypusine synthase. We have found that free-living ciliates Tetrahymena and Paramecium lost the eukaryotic genes encoding spermidine biosynthesis: S-adenosylmethionine decarboxylase (AdoMetDC) and spermidine synthase (SpdSyn). In Tetrahymena, they were replaced by a gene encoding a fusion protein of bacterial AdoMetDC and SpdSyn, present as three copies. In Paramecium, a bacterial homospermidine synthase replaced the eukaryotic genes. Individual AdoMetDC-SpdSyn fusion protein paralogues from Tetrahymena exhibit undetectable AdoMetDC activity; however, when two paralogous fusion proteins are mixed, AdoMetDC activity is restored and spermidine is synthesized. Structural modelling indicates a functional active site is reconstituted by sharing critical residues from two defective protomers across the heteromer interface. Paramecium was found to accumulate homospermidine, suggesting it replaces spermidine for growth. To test this concept, a budding yeast spermidine auxotrophic strain was found to grow almost normally with homospermidine instead of spermidine. Biosynthesis of spermidine analogue aminopropylcadaverine, but not exogenously provided norspermidine, correlated with some growth. Finally, we found that diverse single-celled eukaryotic parasites and multicellular metazoan Schistosoma worms have lost the spermidine biosynthetic pathway but retain deoxyhypusine synthase. © 2015 John Wiley & Sons Ltd.
A plant spermine oxidase/dehydrogenase regulated by the proteasome and polyamines.
Ahou, Abdellah; Martignago, Damiano; Alabdallah, Osama; Tavazza, Raffaela; Stano, Pasquale; Macone, Alberto; Pivato, Micaela; Masi, Antonio; Rambla, Jose L; Vera-Sirera, Francisco; Angelini, Riccardo; Federico, Rodolfo; Tavladoraki, Paraskevi
2014-04-01
Polyamine oxidases (PAOs) are flavin-dependent enzymes involved in polyamine catabolism. In Arabidopsis five PAO genes (AtPAO1-AtPAO5) have been identified which present some common characteristics, but also important differences in primary structure, substrate specificity, subcellular localization, and tissue-specific expression pattern, differences which may suggest distinct physiological roles. In the present work, AtPAO5, the only so far uncharacterized AtPAO which is specifically expressed in the vascular system, was partially purified from 35S::AtPAO5-6His Arabidopsis transgenic plants and biochemically characterized. Data presented here allow AtPAO5 to be classified as a spermine dehydrogenase. It is also shown that AtPAO5 oxidizes the polyamines spermine, thermospermine, and N(1)-acetylspermine, the latter being the best in vitro substrate of the recombinant enzyme. AtPAO5 also oxidizes these polyamines in vivo, as was evidenced by analysis of polyamine levels in the 35S::AtPAO5-6His Arabidopsis transgenic plants, as well as in a loss-of-function atpao5 mutant. Furthermore, subcellular localization studies indicate that AtPAO5 is a cytosolic protein undergoing proteasomal control. Positive regulation of AtPAO5 expression by polyamines at the transcriptional and post-transcriptional level is also shown. These data provide new insights into the catalytic properties of the PAO gene family and the complex regulatory network controlling polyamine metabolism.
Characterization of antilipolytic action of polyamines in isolated rat adipocytes.
Richelsen, B; Pedersen, S B; Hougaard, D M
1989-01-01
The interactions of polyamines with the lipolytic system were studied in isolated rat adipocytes. Spermine, spermidine and putrescine significantly inhibited adenosine deaminase-stimulated lipolysis. An antilipolytic effect of spermine was detectable at a concentration of 0.25 mM (P less than 0.05). At a concentration of 10 mM all three polyamines inhibited the stimulated lipolysis by 50-60% (P less than 0.001). In addition, spermine enhanced the antilipolytic sensitivity of insulin. Spermine (1 mM) decreased the half-maximal inhibitory concentration of insulin from 320 +/- 70 pM to 56 +/- 20 pM (P less than 0.01). The antilipolytic effects and the cyclic-AMP-lowering effects of the polyamines were almost completely prevented in the presence of different phosphodiesterase (PDE) inhibitors (3-isobutyl-1-methylxanthine and RO 20-1724) and, in addition, polyamines had no effect on lipolysis stimulated by dibutyryl cyclic AMP, indicating that polyamines may inhibit lipolysis by activating the PDE enzyme. This latter suggestion was confirmed by demonstrating that spermine (5 mM) significantly enhanced the low-Km PDE enzyme activity (P less than 0.01). Finally, the amounts of polyamines present in isolated adipocytes were measured, and the estimated cytoplasmic concentrations were 0.02 mM (putrescine), 0.86 mM (spermidine), and 1.0 mM (spermine). It is concluded that polyamines may possibly be involved in the physiological regulation of triacylglycerol mobilization in adipocytes. PMID:2476118
Li, Bo; Wang, Xudong; Guo, Yali; Iqbal, Anam; Dong, Yaping; Li, Wu; Liu, Weisheng; Qin, Wenwu; Chen, Shizhen; Zhou, Xin; Yang, Yunhuang
2016-04-07
A one-step hydrothermal method was developed to fabricate Fe3O4-carbon dots (Fe3O4-CDs) magnetic-fluorescent hybrid nanoparticles (NPs). Ferric ammonium citrate (FAC) was used as a cheap and nontoxic iron precursor and as the carbon source. Moreover, triethylenetetramine (TETA) was used to improve the adhesive strength of CDs on Fe3O4 and the fluorescence intensity of CDs. The prepared water-soluble hybrid NPs not only exhibit excellent superparamagnetic properties (Ms = 56.8 emu g(-1)), but also demonstrate excitation-independent photoluminescence for down-conversion and up-conversion at 445 nm. Moreover, the prepared water-soluble Fe3O4-CDs hybrid NPs have a dual modal imaging ability for both magnetic resonance imaging (MRI) and fluorescence imaging.
Li, Mingkai; Sun, Yan; Tomiya, Noboru; Hsu, Yuchao; Chai, Toby C
2013-08-15
Increased polyamine signaling in bladder urothelial cells (BUC) may play a role in the pathophysiology of overactive bladder (OAB). We quantitated intracellular polyamine levels in cultured BUC from OAB and asymptomatic (NB) subjects. We assessed whether polyamines modulated rapid intracellular calcium ([Ca(2+)]i) changes and delayed acetylcholine (ACh) release evoked by oxotremorine (OXO, a muscarinic agonist). BUC were cultured from cystoscopic biopsies. High-performance liquid chromatography (HPLC) quantitated intracellular putrescine, spermidine, and spermine levels. Five-millimeter difluoromethylornithine (DFMO), and one-millimeter methylglyoxalbisguanylhydrazone (MGBG) treatments were used to deplete intracellular polyamines. Ten micrometers of OXO were used to increase [Ca(2+)]i levels (measured by fura 2 microfluorimetry) and trigger extracellular ACh release (measured by ELISA). Polyamine levels were elevated in OAB compared with NB BUC (0.5 ± 0.15 vs. 0.16 ± 0.03 nmol/mg for putrescine, 2.4 ± 0.21 vs. 1.01 ± 0.13 nmol/mg for spermidine, and 1.90 ± 0.27 vs. 0.86 ± 0.26 nmol/mg for spermine; P < 0.05 for all comparisons). OXO evoked greater [Ca(2+)]i rise in OAB (205.10 ± 18.82% increase over baseline) compared with in NB BUC (119.54 ± 13.01%; P < 0.05). After polyamine depletion, OXO evoked [Ca(2+)]i rise decreased in OAB and NB BUC to 43.40 ± 6.45 and 38.82 ± 3.5%, respectively. OXO tended to increase ACh release by OAB vs. NB BUC (9.02 ± 0.1 vs. 7.04 ± 0.09 μM, respectively; P < 0.05). Polyamine depletion reduced ACh release by both OAB and NB BUC. In conclusion, polyamine levels were elevated twofold in OAB BUC. OXO evoked greater increase in [Ca(2+)]i and ACh release in OAB BUC, although these two events may be unrelated. Depletion of polyamines caused OAB BUC to behave similarly to NB BUC.
Li, Mingkai; Sun, Yan; Tomiya, Noboru; Hsu, Yuchao
2013-01-01
Increased polyamine signaling in bladder urothelial cells (BUC) may play a role in the pathophysiology of overactive bladder (OAB). We quantitated intracellular polyamine levels in cultured BUC from OAB and asymptomatic (NB) subjects. We assessed whether polyamines modulated rapid intracellular calcium ([Ca2+]i) changes and delayed acetylcholine (ACh) release evoked by oxotremorine (OXO, a muscarinic agonist). BUC were cultured from cystoscopic biopsies. High-performance liquid chromatography (HPLC) quantitated intracellular putrescine, spermidine, and spermine levels. Five-millimeter difluoromethylornithine (DFMO), and one-millimeter methylglyoxalbisguanylhydrazone (MGBG) treatments were used to deplete intracellular polyamines. Ten micrometers of OXO were used to increase [Ca2+]i levels (measured by fura 2 microfluorimetry) and trigger extracellular ACh release (measured by ELISA). Polyamine levels were elevated in OAB compared with NB BUC (0.5 ± 0.15 vs. 0.16 ± 0.03 nmol/mg for putrescine, 2.4 ± 0.21 vs. 1.01 ± 0.13 nmol/mg for spermidine, and 1.90 ± 0.27 vs. 0.86 ± 0.26 nmol/mg for spermine; P < 0.05 for all comparisons). OXO evoked greater [Ca2+]i rise in OAB (205.10 ± 18.82% increase over baseline) compared with in NB BUC (119.54 ± 13.01%; P < 0.05). After polyamine depletion, OXO evoked [Ca2+]i rise decreased in OAB and NB BUC to 43.40 ± 6.45 and 38.82 ± 3.5%, respectively. OXO tended to increase ACh release by OAB vs. NB BUC (9.02 ± 0.1 vs. 7.04 ± 0.09 μM, respectively; P < 0.05). Polyamine depletion reduced ACh release by both OAB and NB BUC. In conclusion, polyamine levels were elevated twofold in OAB BUC. OXO evoked greater increase in [Ca2+]i and ACh release in OAB BUC, although these two events may be unrelated. Depletion of polyamines caused OAB BUC to behave similarly to NB BUC. PMID:23698115
Mucosal polyamine metabolism in the columnar lined oesophagus.
Gray, M R; Wallace, H M; Goulding, H; Hoffman, J; Kenyon, W E; Kingsnorth, A N
1993-01-01
Mucosal ornithine decarboxylase activity and polyamine content has been proposed as a possible marker for malignant potential in gastrointestinal mucosa. Polyamine content and histological findings were examined in 107 pairs of endoscopic biopsy specimens taken from gastric fundus, fundic and specialised Barrett's oesophagus and Barrett's adenocarcinoma. The content of putrescine (median nmol/mg protein, range) the primary product of ornithine decarboxylase showed a progressive increase from gastric fundus (0.41, 0.15-1.5); fundic (0.45, 0.01-4.08); specialised Barrett's oesophagus (0.54, 0.01-2.0); dysplastic columnar lined oesophagus (0.56, 0.31-3.1) to adenocarcinoma (1.23, 0.29-8.98). Adenocarcinoma putrescine content was significantly greater than gastric fundus (p < 0.018) and fundic (p < 0.03). Mucosal spermine, spermidine, and total polyamine values were greater in gastric fundus than fundic, specialised Barrett's oesophagus, and dysplastic columnar lined oesophagus (all p < 0.001) suggesting failure to further metabolise putrescine to its higher polyamines in the metaplastic epithelium. Although metaplastic columnar lined oesophagus shows significant differences in polyamine metabolic activity from the stomach the important distinction between specialised and dysplastic columnar lined oesophagus cannot be made by measuring the polyamine content. PMID:8504955
NMR of α-synuclein–polyamine complexes elucidates the mechanism and kinetics of induced aggregation
Fernández, Claudio O; Hoyer, Wolfgang; Zweckstetter, Markus; Jares-Erijman, Elizabeth A; Subramaniam, Vinod; Griesinger, Christian; Jovin, Thomas M
2004-01-01
The aggregation of α-synuclein is characteristic of Parkinson's disease (PD) and other neurodegenerative synucleinopathies. The 140-aa protein is natively unstructured; thus, ligands binding to the monomeric form are of therapeutic interest. Biogenic polyamines promote the aggregation of α-synuclein and may constitute endogenous agents modulating the pathogenesis of PD. We characterized the complexes of natural and synthetic polyamines with α-synuclein by NMR and assigned the binding site to C-terminal residues 109–140. Dissociation constants were derived from chemical shift perturbations. Greater polyamine charge (+2 → +5) correlated with increased affinity and enhancement of fibrillation, for which we propose a simple kinetic mechanism involving a dimeric nucleation center. According to the analysis, polyamines increase the extent of nucleation by ∼104 and the rate of monomer addition ∼40-fold. Significant secondary structure is not induced in monomeric α-synuclein by polyamines at 15°C. Instead, NMR reveals changes in a region (aa 22–93) far removed from the polyamine binding site and presumed to adopt the β-sheet conformation characteristic of fibrillar α-synuclein. We conclude that the C-terminal domain acts as a regulator of α-synuclein aggregation. PMID:15103328
Sánchez-Rodríguez, E; Romero, L; Ruiz, J M
2016-01-15
Polyamines, small aliphatic polycations, have been suggested to play key roles in a number of biological processes. In this paper, attempts were made to investigate the possibility of improving antioxidant response of tomato fruits in relation with endogenous free polyamines content. We studied the reactive oxygen species and polyamines content, and antioxidant and polyamine-biosynthesis enzyme activities in fruits of ungrafted and grafted tomato plants under moderate water stress. We used a drought-tolerant cultivar (Zarina) and drought-sensitive cultivar (Josefina) to obtain reciprocal graft, selfgraft and ungraft plants. Fruits contained higher endogenous polyamine content during the course of the experiment relative to the control, coupled with higher arginine decarboxylase and spermine synthase activities in Zarina ungrafted and ZarxJos. In these cultivars, tomato fruits showed a lower reactive oxygen species generation and higher catalase and superoxide dismutase activities, suggesting that a higher content in polyamines (especially spermine) exerted a positive effect on antioxidant systems. All of these data suggest that spermine leads to more effective reactive oxygen species scavenging (less tissue damage) in tomato fruits, which may function collectively to enhance dehydration tolerance. Copyright © 2015 Elsevier GmbH. All rights reserved.
Csomós, Krisztián; Kristóf, Endre; Jakob, Bernadett; Csomós, István; Kovács, György; Rotem, Omri; Hodrea, Judit; Bagoly, Zsuzsa; Muszbek, Laszlo; Balajthy, Zoltán; Csősz, Éva; Fésüs, László
2016-08-11
Neutrophil extracellular trap (NET) ejected from activated dying neutrophils is a highly ordered structure of DNA and selected proteins capable to eliminate pathogenic microorganisms. Biochemical determinants of the non-randomly formed stable NETs have not been revealed so far. Studying the formation of human NETs we have observed that polyamines were incorporated into the NET. Inhibition of myeloperoxidase, which is essential for NET formation and can generate reactive chlorinated polyamines through hypochlorous acid, decreased polyamine incorporation. Addition of exogenous primary amines that similarly to polyamines inhibit reactions catalyzed by the protein cross-linker transglutaminases (TGases) has similar effect. Proteomic analysis of the highly reproducible pattern of NET components revealed cross-linking of NET proteins through chlorinated polyamines and ɛ(γ-glutamyl)lysine as well as bis-γ-glutamyl polyamine bonds catalyzed by the TGases detected in neutrophils. Competitive inhibition of protein cross-linking by monoamines disturbed the cross-linking pattern of NET proteins, which resulted in the loss of the ordered structure of the NET and significantly reduced capacity to trap bacteria. Our findings provide explanation of how NETs are formed in a reproducible and ordered manner to efficiently neutralize microorganisms at the first defense line of the innate immune system.
Csomós, Krisztián; Kristóf, Endre; Jakob, Bernadett; Csomós, István; Kovács, György; Rotem, Omri; Hodrea, Judit; Bagoly, Zsuzsa; Muszbek, Laszlo; Balajthy, Zoltán; Csősz, Éva; Fésüs, László
2016-01-01
Neutrophil extracellular trap (NET) ejected from activated dying neutrophils is a highly ordered structure of DNA and selected proteins capable to eliminate pathogenic microorganisms. Biochemical determinants of the non-randomly formed stable NETs have not been revealed so far. Studying the formation of human NETs we have observed that polyamines were incorporated into the NET. Inhibition of myeloperoxidase, which is essential for NET formation and can generate reactive chlorinated polyamines through hypochlorous acid, decreased polyamine incorporation. Addition of exogenous primary amines that similarly to polyamines inhibit reactions catalyzed by the protein cross-linker transglutaminases (TGases) has similar effect. Proteomic analysis of the highly reproducible pattern of NET components revealed cross-linking of NET proteins through chlorinated polyamines and ɛ(γ-glutamyl)lysine as well as bis-γ-glutamyl polyamine bonds catalyzed by the TGases detected in neutrophils. Competitive inhibition of protein cross-linking by monoamines disturbed the cross-linking pattern of NET proteins, which resulted in the loss of the ordered structure of the NET and significantly reduced capacity to trap bacteria. Our findings provide explanation of how NETs are formed in a reproducible and ordered manner to efficiently neutralize microorganisms at the first defense line of the innate immune system. PMID:27512953
Igarashi, K; Morris, D R
1984-11-01
Previous results have suggested that ethylglyoxal bis(guanylhydrazone) is a more specific inhibitor of polyamine biosynthesis than the widely used methylglyoxal bis(guanylhydrazone). The physiological effects on mitogenically activated lymphocytes of polyamine depletion with ethylglyoxal bis(guanylhydrazone) were examined. In the presence of ethylglyoxal bis(guanylhydrazone) and the ornithine decarboxylase inhibitor alpha-difluoromethylornithine, the cellular contents of putrescine, spermidine, and spermine were decreased by 75 to 90, 65 to 80, and 40 to 60%, respectively, compared with control cultures. Inhibition of DNA synthesis in these polyamine-deficient cells was always greater than that of protein synthesis. Upon addition of spermidine to the deficient cells, the cellular spermidine content was restored within 4 hr, but the complete recovery of macromolecular synthesis took 10 to 20 hr. Thymidine kinase and DNA polymerase alpha activities in polyamine-deficient cells were lower than those in normal cells, whereas RNA polymerase II and leucyl transfer RNA synthase activities were nearly equal to those in normal cells. These results and studies with 2-dimensional gel electrophoresis raise the possibility that polyamines may regulate the synthesis of specific proteins. Decreased synthesis of replication proteins in polyamine-deficient cells may be one reason for the reduced synthesis of DNA.
Absence of diamine oxidase activity from rabbit and rat lungs.
Rao, S B; Rao, K S; Mehendale, H M
1986-01-01
To study the presence of diamine oxidase (DAO) activity in any tissue with putrescine as the substrate, it is necessary to use inhibitors to block all pathways that could further metabolize gamma-aminobutyraldehyde, which is the product of enzyme reaction. It is also necessary to inhibit any enzyme that may convert putrescine into higher polyamines. By this approach it was observed that lung tissue of both rat and rabbit exhibited no DAO activity. DAO activity was observed in the rat and rabbit intestine, the former showing 3 times as much activity as the latter. The other potential pathways of putrescine metabolism are of no consequence in the rat and rabbit intestine and lungs. PMID:3087348
Barone, Sharon; Destefano-Shields, Christina; Brooks, Marybeth; Murray-Stewart, Tracy; Dunworth, Matthew; Li, Weimin; Doherty, Joanne R.; Hall, Mark A.; Smith, Roger D.; Cleveland, John L.; Casero, Robert A.; Soleimani, Manoocher
2017-01-01
Cisplatin-induced nephrotoxicity limits its use in many cancer patients. The expression of enzymes involved in polyamine catabolism, spermidine/spermine N1-acetyltransferase (SSAT) and spermine oxidase (SMOX) increase in the kidneys of mice treated with cisplatin. We hypothesized that enhanced polyamine catabolism contributes to tissue damage in cisplatin acute kidney injury (AKI). Using gene knockout and chemical inhibitors, the role of polyamine catabolism in cisplatin AKI was examined. Deficiency of SSAT, SMOX or neutralization of the toxic products of polyamine degradation, H2O2 and aminopropanal, significantly diminished the severity of cisplatin AKI. In vitro studies demonstrated that the induction of SSAT and elevated polyamine catabolism in cells increases the phosphorylation of eukaryotic translation initiation factor 2α (eIF2α) and enhances the expression of binding immunoglobulin protein BiP/GRP78) and CCAAT-enhancer-binding protein homologous protein (CHOP/GADD153). The increased expression of these endoplasmic reticulum stress response (ERSR) markers was accompanied by the activation of caspase-3. These results suggest that enhanced polyamine degradation in cisplatin AKI may lead to tubular damage through the induction of ERSR and the consequent onset of apoptosis. In support of the above, we show that the ablation of the SSAT or SMOX gene, as well as the neutralization of polyamine catabolism products modulate the onset of ERSR (e.g. lower BiP and CHOP) and apoptosis (e.g. reduced activated caspase-3). These studies indicate that enhanced polyamine catabolism and its toxic products are important mediators of ERSR and critical to the pathogenesis of cisplatin AKI. PMID:28886181
Zahedi, Kamyar; Barone, Sharon; Destefano-Shields, Christina; Brooks, Marybeth; Murray-Stewart, Tracy; Dunworth, Matthew; Li, Weimin; Doherty, Joanne R; Hall, Mark A; Smith, Roger D; Cleveland, John L; Casero, Robert A; Soleimani, Manoocher
2017-01-01
Cisplatin-induced nephrotoxicity limits its use in many cancer patients. The expression of enzymes involved in polyamine catabolism, spermidine/spermine N1-acetyltransferase (SSAT) and spermine oxidase (SMOX) increase in the kidneys of mice treated with cisplatin. We hypothesized that enhanced polyamine catabolism contributes to tissue damage in cisplatin acute kidney injury (AKI). Using gene knockout and chemical inhibitors, the role of polyamine catabolism in cisplatin AKI was examined. Deficiency of SSAT, SMOX or neutralization of the toxic products of polyamine degradation, H2O2 and aminopropanal, significantly diminished the severity of cisplatin AKI. In vitro studies demonstrated that the induction of SSAT and elevated polyamine catabolism in cells increases the phosphorylation of eukaryotic translation initiation factor 2α (eIF2α) and enhances the expression of binding immunoglobulin protein BiP/GRP78) and CCAAT-enhancer-binding protein homologous protein (CHOP/GADD153). The increased expression of these endoplasmic reticulum stress response (ERSR) markers was accompanied by the activation of caspase-3. These results suggest that enhanced polyamine degradation in cisplatin AKI may lead to tubular damage through the induction of ERSR and the consequent onset of apoptosis. In support of the above, we show that the ablation of the SSAT or SMOX gene, as well as the neutralization of polyamine catabolism products modulate the onset of ERSR (e.g. lower BiP and CHOP) and apoptosis (e.g. reduced activated caspase-3). These studies indicate that enhanced polyamine catabolism and its toxic products are important mediators of ERSR and critical to the pathogenesis of cisplatin AKI.
Innovative approaches to the use of polyamines for DNA nanoparticle preparation for gene therapy.
Vijayanathan, Veena; Agostinelli, Enzo; Thomas, Thresia; Thomas, T J
2014-03-01
Advances in genomic technologies, such as next generation sequencing and disease specific gene targeting through anti-sense, anti-gene, siRNA and microRNA approaches require the transport of nucleic acid drugs through the cell membrane. Membrane transport of DNA/RNA drugs is an inefficient process, and the mechanism(s) by which this process occurs is not clear. A pre-requisite for effective transport of DNA and RNA in cells is their condensation to nanoparticles of ~100 nm size. Although viral vectors are effective in gene therapy, the immune response elicited by viral proteins poses a major challenge. Multivalent cations, such as natural polyamines are excellent promoters of DNA/RNA condensation to nanoparticles. During the past 20 years, our laboratory has synthesized and tested several analogs of the natural polyamine, spermine, for their efficacy to provoke DNA condensation to nanoparticles. We determined the thermodynamics of polyamine-mediated DNA condensation, measured the structural specificity effects of polyamine analogs in facilitating the cellular uptake of oligonucleotides, and evaluated the gene silencing activity of DNA nanoparticles in breast cancer cells. Polyamine-complexed oligonucleotides showed a synergistic effect on target gene inhibition at the mRNA level compared to the use of polyamines and oligonucleotides as single agents. Ionic and structural specificity effects were evident in DNA condensation and cellular transportation effects of polyamines. In condensed DNA structures, correlation exists between the attractive and repulsive forces with structurally different polyamines and cobalt hexamine, indicating the existence of a common force in stabilizing the condensed structures. Future studies aimed at defining the mechanism(s) of DNA compaction and structural features of DNA nanoparticles might aid in the development of novel gene delivery vehicles.
Mechanisms of asbestos-induced squamous metaplasia in tracheobronchial epithelial cells.
Cameron, G; Woodworth, C D; Edmondson, S; Mossman, B T
1989-01-01
Within 1 to 4 weeks after exposure to asbestos, differentiated rodent and human tracheobronchial epithelial cells in organ culture undergo squamous metaplasia, a putative preneoplastic lesion characterized by conversion of mucociliary cell types to keratinizing cells. The exogenous addition of retinal acetate (RA) to culture medium of hamster tracheal organ cultures reverses preestablished, asbestos-induced squamous metaplasia, although data suggest that the effectiveness of RA decreases as the length of time between exposure to asbestos and initial application of RA increases. alpha-Difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase (ODC), inhibits squamous metaplasia caused by asbestos or vitamin A deficiency, whereas addition of methylglyoxal bis(guanylhydrazone) (MGBG), a structural analog of spermidine and inhibitor of S-adenosylmethionine decarboxylase, causes an enhancement of metaplasia under both circumstances. Basal cell hyperplasia and increased incorporation of 3H-thymidine by tracheal epithelial cells also are seen after addition of the polyamines, putrescine or spermidine, to tracheal organ cultures, an observation supporting the importance of polyamines in the development of this lesion. The use of retinoids and inhibitors of ODC could be promising as preventive and/or therapeutic approaches for individuals at high risk for development of asbestos-associated diseases. PMID:2924752
Metabolic Pathways Regulated by Chitosan Contributing to Drought Resistance in White Clover.
Li, Zhou; Zhang, Yan; Zhang, Xinquan; Merewitz, Emily; Peng, Yan; Ma, Xiao; Huang, Linkai; Yan, Yanhong
2017-08-04
Increased endogenous chitosan (CTS) could be associated with improved drought resistance in white clover (Trifolium repens). Plants were pretreated with or without 1 mg/mL CTS and then were subjected to optimal or water-limited condition in controlled growth chambers for 6 days. Phenotypic and physiological results indicated that exogenous CTS significantly improved drought resistance of white clover. Metabolome results showed that exogenous CTS induced a significant increase in endogenous CTS content during dehydration accompanied by the maintenance of greater accumulation of sugars, sugar alcohols, amino acids, organic acids, and other metabolites (ascorbate, glutathione, flavonoids, putrescine, and spermidine). These compounds are associated with osmotic adjustment, antioxidant defense, stress signaling, and energy metabolism under stress condition. Similarly, transcriptome revealed that many genes in relation to amino acid and carbohydrate metabolism, energy production and conversion, and ascorbate-glutathione and flavonoid metabolism were significantly up-regulated by CTS in response to dehydration stress. CTS-induced drought resistance was associated with the accumulation of stress protective metabolites, the enhancement of ascorbate-glutathione and tricarboxylic acid cycle, and increases in the γ-aminobutyric acid shunt, polyamine synthesis, and flavonoids metabolism contributing to improved osmotic adjustment, antioxidant capacity, stress signaling, and energy production for stress defense, thereby maintaining metabolic homeostasis under dehydration stress.
Inhibition of lytic infection of pseudorabies virus by arginine depletion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, H.-C.; Kao, Y.-C.; Chang, T-J.
2005-08-26
Pseudorabies virus (PRV) is a member of Alphahepesviruses; it is an enveloped virus with a double-stranded DNA genome. Polyamines (such as spermine and spermidine) are ubiquitous in animal cells and participate in cellular proliferation and differentiation. Previous results of our laboratory showed that the PRV can accomplish lytic infection either in the presence of exogenous spermine (or spermidine) or depletion of cellular polyamines. The amino acid arginine is a precursor of polyamine biosynthesis. In this work, we investigated the role of arginine in PRV infection. It was found that the plaque formation of PRV was inhibited by arginase (enzyme catalyzingmore » the conversion of arginine into ornithine and urea) treatment whereas this inhibition can be reversed by exogenous arginine, suggesting that arginine is essential for PRV proliferation. Western blotting was conducted to study the effect of arginine depletion on the levels of structural proteins of PRV in virus-infected cells. Four PRV structural proteins (gB, gE, UL47, and UL48) were chosen for examination, and results revealed that the levels of viral proteins were obviously reduced in long time arginase treatment. However, the overall protein synthesis machinery was apparently not influenced by arginase treatment either in mock or PRV-infected cells. Analyzing with native gel, we found that arginase treatment affected the mobility of PRV structural proteins, suggesting the conformational change of viral proteins by arginine depletion. Heat shock proteins, acting as molecular chaperons, participate in protein folding and translocation. Our results demonstrated that long time arginase treatment could reduce the expression of cellular heat shock proteins 70 (hsc70 and hsp70), and transcriptional suppression of heat shock protein 70 gene promoter was one of the mechanisms involved in this reduced expression.« less
USDA-ARS?s Scientific Manuscript database
Biogenic amines in all organisms including plants affect a myriad of growth and developmental processes. Therefore, there is continued interest in understanding their (here polyamines) biosynthesis and functional roles in regulating plant metabolism, physiology and development. The role of polyamine...
Polyamine Analogues as Novel Anti-HER Family Agents in Human Breast Cancer
2009-10-01
NOTES 14. ABSTRACT Elevated levels of all three naturally occurring polyamines, spermine, spermidine and putrescine, have been found in breast...Introduction The polyamines, spermine, spermidine and putrescine, are naturally occurring aliphatic cations that are essential for normal cell growth and
Yarlett, Nigel; Waters, W. Ray; Harp, James A.; Wannemuehler, Michael J.; Morada, Mary; Bellcastro, Josephine; Upton, Steve J.; Marton, Laurence J.; Frydman, Benjamin J.
2007-01-01
The in vivo effectiveness of a series of conformationally restricted polyamine analogues alone and selected members in combination with dl-α-difluoromethylarginine against Cryptosporidium parvum infection in a T-cell receptor alpha-deficient mouse model was tested. Polyamine analogues were selected from the extended bis(ethyl)-sym-homospermidine or bis(ethyl)-spermine backbone having cis or trans double bonds at the center of the molecule. The cis isomers were found to have significantly greater efficacy in both preventing and curing infection in a mouse model than the trans polyamine analogues when tested in a T-cell receptor alpha-deficient mouse model. When tested in combination with dl-α-difluoromethylarginine, the cis-restricted analogues were found to be more effective in preventing oocyst shedding. This study demonstrates the potential of polyamine analogues as anticryptosporidial agents and highlights the presence of multiple points in polyamine synthesis by this parasite that are susceptible to inhibition resulting in growth inhibition. PMID:17242149
Romero-Calderón, Rafael; Krantz, David E.
2005-01-01
Polyamine transport activities have been described in diverse multicellular systems, but their bioenergetic mechanisms and molecular identity remain unclear. In the present paper, we describe a high-affinity spermine/spermidine transport activity expressed in Drosophila S2 cells. Ion-replacement experiments indicate that polyamine uptake across the cell membrane is Na+-, K+-, Cl−- and Ca2+-independent, but pH-sensitive. Additional experiments using ionophores suggest that polyamine uptake may be H+-coupled. Pharmacological experiments show that polyamine uptake in S2 cells is selectively blocked by MGBG {methylglyoxal bis(guanylhydrazone) or 1,1′-[(methylethanediylidine)-dinitrilo]diguanidine} and paraquat (N,N-dimethyl-4,4′-bipyridylium), two known inhibitors of polyamine uptake in mammalian cells. In addition, inhibitors known to block the Slc22 (solute carrier 22) family of organic anion/cation transporters inhibit spermine uptake in S2 cells. These data and the genetic tools available in Drosophila will facilitate the molecular identification and further characterization of this activity. PMID:16248856
Romero-Calderón, Rafael; Krantz, David E
2006-01-15
Polyamine transport activities have been described in diverse multicellular systems, but their bioenergetic mechanisms and molecular identity remain unclear. In the present paper, we describe a high-affinity spermine/spermidine transport activity expressed in Drosophila S2 cells. Ion-replacement experiments indicate that polyamine uptake across the cell membrane is Na+-, K+-, Cl-- and Ca2+-independent, but pH-sensitive. Additional experiments using ionophores suggest that polyamine uptake may be H+-coupled. Pharmacological experiments show that polyamine uptake in S2 cells is selectively blocked by MGBG {methylglyoxal bis(guanylhydrazone) or 1,1'-[(methylethanediylidine)-dinitrilo]diguanidine} and paraquat (N,N-dimethyl-4,4'-bipyridylium), two known inhibitors of polyamine uptake in mammalian cells. In addition, inhibitors known to block the Slc22 (solute carrier 22) family of organic anion/cation transporters inhibit spermine uptake in S2 cells. These data and the genetic tools available in Drosophila will facilitate the molecular identification and further characterization of this activity.
ERIC Educational Resources Information Center
Maynard, Senko K.
The casual conversation of six pairs of Japanese and six pairs of American colleges students was analyzed for evidence of two related aspects of conversation management: the linguistic characteristics of utterance units and back-channel strategies. Utterance units are defined as those occurring between identifiable pauses or breaks in tempo.…
Parra-Lobato, Maria C.; Gomez-Jimenez, Maria C.
2011-01-01
After fruit ripening, many fruit-tree species undergo massive natural fruit abscission. Olive (Olea europaea L.) is a stone-fruit with cultivars such as Picual (PIC) and Arbequina (ARB) which differ in mature fruit abscission potential. Ethylene (ET) is associated with abscission, but its role during mature fruit abscission remains largely uncharacterized. The present study investigates the possible roles of ET and polyamine (PA) during mature fruit abscission by modulating genes involved in the ET signalling and biosynthesis pathways in the abscission zone (AZ) of both cultivars. Five ET-related genes (OeACS2, OeACO2, OeCTR1, OeERS1, and OeEIL2) were isolated in the AZ and adjacent cells (AZ–AC), and their expression in various olive organs and during mature fruit abscission, in relation to interactions between ET and PA and the expression induction of these genes, was determined. OeACS2, OeACO2, and OeEIL2 were found to be the only genes that were up-regulated in association with mature fruit abscission. Using the inhibition of ET and PA biosynthesis, it is demonstrated that OeACS2 and OeEIL2 expression are under the negative control of PA while ET induces their expression in AZ–AC. Furthermore, mature fruit abscission depressed nitric oxide (NO) production present mainly in the epidermal cells and xylem of the AZ. Also, NO production was differentially responsive to ET, PA, and different inhibitors. Taken together, the results indicate that PA-dependent ET signalling and biosynthesis pathways participate, at least partially, during mature fruit abscission, and that endogenous NO and 1-aminocyclopropane-1-carboxylic acid maintain an inverse correlation, suggesting an antagonistic action of NO and ET in abscission signalling. PMID:21633085
Transgenic manipulation of the metabolism of polyamines in poplar cells
Pratiksha Bhatnagar; Bernadette M. Glasheen; Suneet K. Bains; Stephanie L. Long; Rakesh Minocha; Christian Walter; Subhash C. Minocha
2001-01-01
The metabolism of polyamines (putrescine, spermidine, and spermine) has become the target of genetic manipulation because of their significance in plant development and possibly stress tolerance. We studied the polyamine metabolism in non-transgenic (NT) and transgenic cells of poplar (Populus nigra 3 maximowiczii) expressing a...
Code of Federal Regulations, 2013 CFR
2013-07-01
..., propylene glycol diamine and aliphatic polyamine, N-(1,3 -dimethylbutylidene) derivs (generic). 721.10189...-phenol polymer glycidyl ether, morpholinepropanamine, propylene glycol diamine and aliphatic polyamine, N..., propylene glycol diamine and aliphatic polyamine, N-(1,3 -dimethylbutylidene) derivs (PMN P-05-186, Chemical...
Code of Federal Regulations, 2014 CFR
2014-07-01
..., propylene glycol diamine and aliphatic polyamine, N-(1,3 -dimethylbutylidene) derivs (generic). 721.10189...-phenol polymer glycidyl ether, morpholinepropanamine, propylene glycol diamine and aliphatic polyamine, N..., propylene glycol diamine and aliphatic polyamine, N-(1,3 -dimethylbutylidene) derivs (PMN P-05-186, Chemical...
Code of Federal Regulations, 2012 CFR
2012-07-01
..., propylene glycol diamine and aliphatic polyamine, N-(1,3 -dimethylbutylidene) derivs (generic). 721.10189...-phenol polymer glycidyl ether, morpholinepropanamine, propylene glycol diamine and aliphatic polyamine, N..., propylene glycol diamine and aliphatic polyamine, N-(1,3 -dimethylbutylidene) derivs (PMN P-05-186, Chemical...
40 CFR 721.6440 - Polyamine urea-for-malde-hyde condensate (specific name).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyamine urea-for-malde-hyde condensate (specific name). 721.6440 Section 721.6440 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.6440 Polyamine urea-for-malde-hyde condensate...
Cheetham, B F; Shaw, D C; Bellett, A J
1982-01-01
Adenovirus type 5 induces cellular DNA synthesis and thymidine kinase in quiescent rat cells but does not induce ornithine decarboxylase. We now show that unlike serum, adenovirus type 5 fails to induce S-adenosylmethionine decarboxylase or polyamine accumulation. The inhibition by methylglyoxal bis(guanylhydrazone) of the induction of thymidine kinase by adenovirus type 5 is probably unrelated to its effects on polyamine biosynthesis. Thus, induction of cellular thymidine kinase and DNA replication by adenovirus type 5 is uncoupled from polyamine accumulation. PMID:7177112
Current Status of the Polyamine Research Field
Pegg, Anthony E.; Casero, Robert A.
2013-01-01
This chapter provides an overview of the polyamine field and introduces the 32 other chapters that make up this volume. These chapters provide a wide range of methods, advice, and background relevant to studies of the function of polyamines, the regulation of their content, their role in disease, and the therapeutic potential of drugs targeting polyamine content and function. The methodology provided in this new volume will enable laboratories already working in this area to expand their experimental techniques and facilitate the entry of additional workers into this rapidly expanding field. PMID:21318864
Khettab, N; Amory, M C; Briand, G; Bousquet, B; Combre, A; Forlot, P; Barey, M
1988-12-01
The purpose of this study was to confirm the photoprotective effect on skin of vitamins A and E, due to inhibition of polyamine synthesis and production of free radicals. These variables were measured in the lumbar epidermis of the female hairless mouse subjected to UVA + B irradiation. Polyamines were assayed in epidermal homogenate by HPLC, and production of oxygenated free radicals was determined by spectrofluorometric assay of malonyl dialdehyde. It was determined that butyl-hydroxy-toluene and vitamin E inhibited production of free radicals (56% and 60%, respectively) and caused a significant reduction in polyamine biosynthesis (P less than 0.01), whereas the inhibitory effect of malonyl dialdehyde induced by vitamin A (30%) had no associated effect on polyamine metabolism.
Thomas, T J; Thomas, Thresia
2018-03-13
Polyamine levels are elevated in breast tumors compared to those of adjacent normal tissues. The female sex hormone, estrogen is implicated in the origin and progression of breast cancer. Estrogens stimulate and antiestrogens suppress the expression of polyamine biosynthetic enzyme, ornithine decarboxylate (ODC). Using several bis(ethyl)spermine analogues, we found that these analogues inhibited the proliferation of estrogen receptor-positive and estrogen receptor negative breast cancer cells in culture. There was structure-activity relationship in the efficacy of these compounds in suppressing cell growth. The activity of ODC was inhibited by these compounds, whereas the activity of the catabolizing enzyme, spermidine/spermine N ¹-acetyl transferase (SSAT) was increased by 6-fold by bis(ethyl)norspermine in MCF-7 cells. In a transgenic mouse model of breast cancer, bis(ethyl)norspermine reduced the formation and growth of spontaneous mammary tumor. Recent studies indicate that induction of polyamine catabolic enzymes SSAT and spermine oxidase (SMO) play key roles in the anti-proliferative and apoptotic effects of polyamine analogues and their combinations with chemotherapeutic agents such as 5-fluorouracil (5-FU) and paclitaxel. Thus, polyamine catabolic enzymes might be important therapeutic targets and markers of sensitivity in utilizing polyamine analogues in combination with other therapeutic agents.
Thomas, Thresia
2018-01-01
Polyamine levels are elevated in breast tumors compared to those of adjacent normal tissues. The female sex hormone, estrogen is implicated in the origin and progression of breast cancer. Estrogens stimulate and antiestrogens suppress the expression of polyamine biosynthetic enzyme, ornithine decarboxylate (ODC). Using several bis(ethyl)spermine analogues, we found that these analogues inhibited the proliferation of estrogen receptor-positive and estrogen receptor negative breast cancer cells in culture. There was structure-activity relationship in the efficacy of these compounds in suppressing cell growth. The activity of ODC was inhibited by these compounds, whereas the activity of the catabolizing enzyme, spermidine/spermine N1-acetyl transferase (SSAT) was increased by 6-fold by bis(ethyl)norspermine in MCF-7 cells. In a transgenic mouse model of breast cancer, bis(ethyl)norspermine reduced the formation and growth of spontaneous mammary tumor. Recent studies indicate that induction of polyamine catabolic enzymes SSAT and spermine oxidase (SMO) play key roles in the anti-proliferative and apoptotic effects of polyamine analogues and their combinations with chemotherapeutic agents such as 5-fluorouracil (5-FU) and paclitaxel. Thus, polyamine catabolic enzymes might be important therapeutic targets and markers of sensitivity in utilizing polyamine analogues in combination with other therapeutic agents. PMID:29533973
The polyamines of Xanthium strumarium and their response to photoperiod.
Hamasaki, N; Galston, A W
1990-01-01
Flowering plants of Xanthium strumarium L., grown in 8 h photoperiods, were analysed for polyamines. Putrescine, spermidine and spermine were found throughout the plant in three forms: (a) as free polyamines; (b) conjugates soluble in 5% trichloracetic acid (TCA); and (c) bound to the TCA-insoluble precipitate. On a fresh weight basis, total polyamines are most abundant in young leaves and buds, especially flower buds. Spermidine predominates in the free polyamine fractions, while spermine is dominant in the conjugated fraction. Transfer of vegetative plants from 16 h photoperiods to 1, 2, 3, or 4 inductive cycles (8 h light + 16 h uninterrupted dark) caused rapid and marked changes in the polyamine titer of the leaves and ultimately, floral initiation. The titer of free putrescine per mg protein declined progressively with induction in all leaf sizes, while the titers of free spermidine and spermine rose during days 2 and 3 in small and expanding leaves. Conjugated putrescine, spermidine and spermine rose sharply after only 1 inductive cycle, especially in small and expanding leaves, and maintained the higher level for at least several cycles. In plants given 4 inductive cycles, buds harvested after 4 additional days had sharply elevated levels of conjugated polyamines, especially spermine, on a protein basis.
1,4-Diaminobutane (putrescine), spermidine, and spermine.
Tabor, C W; Tabor, H
1976-01-01
As is evident from the above summary of the recent literature, plus many other papers not cited here, there is an extensive literature indicating the physiological significance of these amines. The most important studies can be summarized as follows. (a) Polyamines and their biosynthetic enzymes are ubiquitous. (b) Microbiological mutants have been described in which there is a definite requirement of polyamines for growth. (c) The concentration of polyamines and their biosynthesis enzymes increase when the growth rate increases. These increases usually precede or are simultaneous with increases in RNA, DNA, and protein levels. (d) Ornithine decarboxylase has a remarkably fast turnover rate in animal cells, and the level of this enzyme rapidly changes after a variety of growth stimuli. (e) Polyamines have a high affinity for nucleic acids and stabilize their secondary structure. They are found associated with DNA in bacteriophages and have a variety of stimulatory effects on DNA and RNA biosynthesis in vitro. (f) Polyamines stimulate protein synthesis in vivo and in vitro. (g) Polyamines protect spheroplasts and halophilic organisms for lysis, indicating their ability to stabilize membranes. Despite these observations, no specific mechanism has been firmly established for the action of the polyamines in vivo. It is clear that these compounds are physiologically important, however, and further work is necessary to establish the mechanism of their action.
Kumamoto, E
1996-12-01
Excitatory amino-acid currents in rodent central neurones are mediated by the activation of glutamate receptors. Ionotropic types of the receptors are divided into alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA), kainate and N-methyl-D-aspartate (NMDA) receptors, and the former two are collectively called non-NMDA receptors. The NMDA receptor is modulated by a number of endogenous neuromodulators including Mg2+, polyamines, glycine and protons in extracellular solutions. Although it has been generally thought that each of the neuromodulators acts on a distinct site in the NMDA receptor, recent studies have revealed that these actions may be not necessarily independent of each other. The NMDA receptor response is not only inhibited but also potentiated by Mg2+, and the latter action is due to an interaction of a Mg2+ site with either glycine- or proton-binding site. In the presence of polyamines, a tonic inhibition by protons of the NMDA receptor response is relieved, resulting in a potentiation of the response. Alternatively, it has been recently revealed that there are some subtypes of non-NMDA receptors which are negatively modulated by polyamines in either extra- or intra cellular solutions. The difference in polyamine sensitivity among non-NMDA receptors is attributed to a distinction in their constituted subunits. The inhibition of non-NMDA receptor by intracellular polyamines results in inward rectification of the current-voltage relation which is not seen for polyamine-insensitive ones. This polyamine action is not mimicked by intracellular Mg2+.
Salazar-Badillo, Fatima Berenice; Sánchez-Rangel, Diana; Becerra-Flora, Alicia; López-Gómez, Miguel; Nieto-Jacobo, Fernanda; Mendoza-Mendoza, Artemio; Jiménez-Bremont, Juan Francisco
2015-10-01
Plants are associated with a wide range of microorganisms throughout their life cycle, and some interactions result on plant benefits. Trichoderma species are plant beneficial fungi that enhance plant growth and development, contribute to plant nutrition and induce defense responses. Nevertheless, the molecules involved in these beneficial effects still need to be identify. Polyamines are ubiquitous molecules implicated in plant growth and development, and in the establishment of plant microbe interactions. In this study, we assessed the polyamine profile in Arabidopsis plants during the interaction with Trichoderma virens and Trichoderma atroviride, using a system that allows direct plant-fungal contact or avoids their physical interaction (split system). The plantlets that grew in the split system exhibited higher biomass than the ones in direct contact with Trichoderma species. After 3 days of interaction, a significant decrease in Arabidopsis polyamine levels was observed in both systems (direct contact and split). After 5 days of interaction polyamine levels were increased. The highest levels were observed with T. atroviride (split system), and with T. virens (direct contact). The expression levels of Arabidopsis ADC1 and ADC2 genes during the interaction with the fungi were also assessed. We observed a time dependent regulation of ADC1 and ADC2 genes, which correlates with polyamine levels. Our data show an evident change in polyamine profile during Arabidopsis - Trichoderma interaction, accompanied by evident alterations in plant root architecture. Polyamines could be involved in the changes undergone by plant during the interaction with this beneficial fungus. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Atiya Ali, M; Strandvik, B; Sabel, K-G; Palme Kilander, C; Strömberg, R; Yngve, A
2014-10-01
Polyamine intake from milk is considered essential for post-natal maturation of the immune system and small intestine. The present study aimed to determine polyamine content in human milk after preterm delivery and the association with mothers' dietary intake. In comparison, the polyamine levels were compared with those in term breast milk and some corresponding formulas. Transitional breast milk was collected from 40 mothers delivering after 24-36 weeks of gestation, and from 12 mothers delivering after full term. Food intake was assessed in mothers delivering preterm babies using a 3-day diary. Polyamines were analysed by high-performance liquid chromatography. The dietary intake of polyamines was significantly associated with breast milk content but weaker for spermine than for spermidine and putrescine. Total polyamine level was higher in preterm than term milk and lower in the corresponding formulas. Putrescine, spermidine and spermine contents [mean (SEM)] in preterm milk were 165.6 (25), 615.5 (80) and 167.7 (16) nmol dL⁻¹, respectively, with the levels of putrescine and spermidine being 50% and 25% higher than in term milk. The content of spermine did not differ. Dietary intake of polyamines has an impact on the content in breast milk. The difference between human milk after preterm and term delivery might be considered when using donor human milk for preterm infants. The corresponding formulas had lower contents. Further studies are important for determining the relationship between tissue growth and maturation and optimal intake. © 2013 The British Dietetic Association Ltd.
Role of polyamines at the G1/S boundary and G2/M phase of the cell cycle.
Yamashita, Tomoko; Nishimura, Kazuhiro; Saiki, Ryotaro; Okudaira, Hiroyuki; Tome, Mayuko; Higashi, Kyohei; Nakamura, Mizuho; Terui, Yusuke; Fujiwara, Kunio; Kashiwagi, Keiko; Igarashi, Kazuei
2013-06-01
The role of polyamines at the G1/S boundary and in the G2/M phase of the cell cycle was studied using synchronized HeLa cells treated with thymidine or with thymidine and aphidicolin. Synchronized cells were cultured in the absence or presence of α-difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase, plus ethylglyoxal bis(guanylhydrazone) (EGBG), an inhibitor of S-adenosylmethionine decarboxylase. When polyamine content was reduced by treatment with DFMO and EGBG, the transition from G1 to S phase was delayed. In parallel, the level of p27(Kip1) was greatly increased, so its mechanism was studied in detail. Synthesis of p27(Kip1) was stimulated at the level of translation by a decrease in polyamine levels, because of the existence of long 5'-untranslated region (5'-UTR) in p27(Kip1) mRNA. Similarly, the transition from the G2/M to the G1 phase was delayed by a reduction in polyamine levels. In parallel, the number of multinucleate cells increased by 3-fold. This was parallel with the inhibition of cytokinesis due to an unusual distribution of actin and α-tubulin at the M phase. Since an association of polyamines with chromosomes was not observed by immunofluorescence microscopy at the M phase, polyamines may have only a minor role in structural changes of chromosomes at the M phase. In general, the involvement of polyamines at the G2/M phase was smaller than that at the G1/S boundary. Copyright © 2013 Elsevier Ltd. All rights reserved.
40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polymer of poly-ethylene-polyamine and... New Uses for Specific Chemical Substances § 721.7260 Polymer of poly-ethylene-polyamine and alkanediol... chemical substance identified generically as polymer of polyethylenepolyamine and alkanediol diglycidyl...
USDA-ARS?s Scientific Manuscript database
Polyamines (PA) involve in the gene regulation by interacting with various anionic macromolecules such as DNA, RNA and proteins and modulating their structure and function. Previous studies have showed that changing in polyamine biosynthesis alters plant response to different abiotic stresses. Here,...
40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Polymer of poly-ethylene-polyamine and... New Uses for Specific Chemical Substances § 721.7260 Polymer of poly-ethylene-polyamine and alkanediol... chemical substance identified generically as polymer of polyethylenepolyamine and alkanediol diglycidyl...
Ornithine: the overlooked molecule in the regulation of polyamine metabolism
Rajtilak Majumdar; Lin Shao; Rakesh Minocha; Stephanie Long; Subhash C. Minocha
2013-01-01
We overexpressed a mouse ornithine decarboxylase gene under the control of a constitutive and an estradiol-inducible promoter in Arabidopsis thaliana to increase our understanding of the regulation of polyamine metabolism. Of particular interest was the role of the substrate ornithine not only in the regulation of polyamine biosynthesis, but also in...
40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Polymer of poly-ethylene-polyamine and... New Uses for Specific Chemical Substances § 721.7260 Polymer of poly-ethylene-polyamine and alkanediol... chemical substance identified generically as polymer of polyethylenepolyamine and alkanediol diglycidyl...
40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Polymer of poly-ethylene-polyamine and... New Uses for Specific Chemical Substances § 721.7260 Polymer of poly-ethylene-polyamine and alkanediol... chemical substance identified generically as polymer of polyethylenepolyamine and alkanediol diglycidyl...
40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Polymer of poly-ethylene-polyamine and... New Uses for Specific Chemical Substances § 721.7260 Polymer of poly-ethylene-polyamine and alkanediol... chemical substance identified generically as polymer of polyethylenepolyamine and alkanediol diglycidyl...
Liu, Taibo; Wook Kim, Dong; Niitsu, Masaru; Berberich, Thomas; Kusano, Tomonobu
2014-01-01
POLYAMINE OXIDASE 1 (OsPAO1), from rice (Oryza sativa), and POLYAMINE OXIDASE 5 (AtPAO5), from Arabidopsis (Arabidopsis thaliana), are enzymes sharing high identity at the amino acid level and with similar characteristics, such as polyamine specificity and pH preference; furthermore, both proteins localize to the cytosol. A loss-of-function Arabidopsis mutant, Atpao5-2, was hypersensitive to low doses of exogenous thermospermine but this phenotype could be rescued by introduction of the wild-type AtPAO5 gene. Introduction of OsPAO1, under the control of a constitutive promoter, into Atpao5-2 mutants also restored normal thermospermine sensitivity, allowing growth in the presence of low levels of thermospermine, along with a concomitant decrease in thermospermine content in plants. By contrast, introduction of OsPAO3, which encodes a peroxisome-localized polyamine oxidase, into Atpao5-2 plants could not rescue any of the mutant phenotypes in the presence of thermospermine. These results suggest that OsPAO1 is the functional ortholog of AtPAO5.
Igarashi, K; Porter, C W; Morris, D R
1984-11-01
Ethylglyoxal bis(guanylhydrazone) (EGBG) was compared as an inhibitor of polyamine biosynthesis with methylglyoxal bis(guanylhydrazone) (MGBG) in bovine small lymphocytes stimulated by concanavalin A. EGBG brought about a decrease in spermidine and spermine levels equal to that found with MGBG, but at a 5-fold lower intracellular drug concentration. Despite identical polyamine levels, the degree of inhibition of DNA and protein synthesis by EGBG was smaller than that observed with MGBG, in either the presence or absence of the ornithine decarboxylase inhibitor, alpha-difluoromethylornithine. It was found that in vitro protein synthesis and in vivo mitochondrial function were inhibited by concentrations of MGBG necessary to inhibit polyamine synthesis in cells (1 to 3 mM), but not by efficacious levels of EGBG (0.2 to 0.6 mM). These results suggest that EGBG is more suitable as a specific inhibitor of polyamine biosynthesis and that use of this drug, rather than MGBG, in combination with alpha-difluoromethylornithine may be useful for studying the physiological functions of polyamines in animal cells.
Dynamic changes in plant secondary metabolites during UV acclimation in Arabidopsis thaliana.
Hectors, Kathleen; Van Oevelen, Sandra; Geuns, Jan; Guisez, Yves; Jansen, Marcel A K; Prinsen, Els
2014-10-01
Plants respond to environmental stress by synthesizing a range of secondary metabolites for defense purposes. Here we report on the effect of chronic ultraviolet (UV) radiation on the accumulation of plant secondary metabolites in Arabidopsis thaliana leaves. In the natural environment, UV is a highly dynamic environmental parameter and therefore we hypothesized that plants are continuously readjusting levels of secondary metabolites. Our data show distinct kinetic profiles for accumulation of tocopherols, polyamines and flavonoids upon UV acclimation. The lipid-soluble antioxidant α-tocopherol accumulated fast and remained elevated. Polyamines accumulated fast and transiently. This fast response implies a role for α-tocopherol and polyamines in short-term UV response. In contrast, an additional sustained accumulation of flavonols took place. The distinct accumulation patterns of these secondary metabolites confirm that the UV acclimation process is a dynamic process, and indicates that commonly used single time-point analyses do not reveal the full extent of UV acclimation. We demonstrate that UV stimulates the accumulation of specific flavonol glycosides, i.e. kaempferol and (to a lesser extent) quercetin di- and triglycosides, all specifically rhamnosylated at position seven. All metabolites were identified by Ultra Performance Liquid Chromatography (UPLC)-coupled tandem mass spectrometry. Some of these flavonol glycosides reached steady-state levels in 3-4 days, while concentrations of others are still increasing after 12 days of UV exposure. A biochemical pathway for these glycosides is postulated involving 7-O-rhamnosylation for the synthesis of all eight metabolites identified. We postulate that this 7-O-rhamnosylation has an important function in UV acclimation. © 2014 Scandinavian Plant Physiology Society.
Kabir, Ayesha; Suresh Kumar, Gopinatha
2013-01-01
Background The thermodynamics of the base pair specificity of the binding of the polyamines spermine, spermidine, putrescine, and cadaverine with three genomic DNAs Clostridium perfringens, 27% GC, Escherichia coli, 50% GC and Micrococcus lysodeikticus, 72% GC have been studied using titration calorimetry and the data supplemented with melting studies, ethidium displacement and circular dichroism spectroscopy results. Methodology/Principal Findings Isothermal titration calorimetry, differential scanning calorimetry, optical melting studies, ethidium displacement, circular dichroism spectroscopy are the various techniques employed to characterize the interaction of four polyamines, spermine, spermidine, putersine and cadaverine with the DNAs. Polyamines bound stronger with AT rich DNA compared to the GC rich DNA and the binding varied depending on the charge on the polyamine as spermine>spermidine >putrescine>cadaverine. Thermodynamics of the interaction revealed that the binding was entropy driven with small enthalpy contribution. The binding was influenced by salt concentration suggesting the contribution from electrostatic forces to the Gibbs energy of binding to be the dominant contributor. Each system studied exhibited enthalpy-entropy compensation. The negative heat capacity changes suggested a role for hydrophobic interactions which may arise due to the non polar interactions between DNA and polyamines. Conclusion/Significance From a thermodynamic analysis, the AT base specificity of polyamines to DNAs has been elucidated for the first time and supplemented by structural studies. PMID:23894663
40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject to...
R. Minocha; S.C. Minocha; A. Komamine; W.C. Shortle
1991-01-01
Various inhibitors of polyamine biosynthesis were used to study the role of polyamines in DNA synthesis and cell division in suspension cultures of Catharanthus roseus (L) G. Don. Arginine decarboxylase (ADC; EC 4.1.1.19) was the major enzyme responsible for putrescine production. DL α-difluoromethylarginine inhibited ADC activity, cellular...
40 CFR 721.10410 - Polyether ester acid compound with a polyamine amide (generic) (P-05-714).
Code of Federal Regulations, 2014 CFR
2014-07-01
... polyamine amide (generic) (P-05-714). 721.10410 Section 721.10410 Protection of Environment ENVIRONMENTAL... polyamine amide (generic) (P-05-714). (a) Chemical substance and significant new uses subject to reporting... amide (PMN P-05-714) is subject to reporting under this section for the significant new uses described...
40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject to...
Acosta-Andrade, Carlos; Lambertos, Ana; Urdiales, José L; Sánchez-Jiménez, Francisca; Peñafiel, Rafael; Fajardo, Ignacio
2016-10-01
Antizymes and antizyme inhibitors are key regulatory proteins of polyamine levels by affecting ornithine decarboxylase and polyamine uptake. Our previous studies indicated a metabolic interplay among polyamines, histamine and serotonin in mast cells, and demonstrated that polyamines are present in mast cell secretory granules, being important for histamine storage and serotonin levels. Recently, the novel antizyme inhibitor-2 (AZIN2) was proposed as a local regulator of polyamine biosynthesis in association with mast cell serotonin-containing granules. To gain insight into the role of AZIN2 in the biosynthesis and storage of serotonin and histamine, we have generated bone marrow derived mast cells (BMMCs) from both wild-type and transgenic Azin2 hypomorphic mice, and have analyzed polyamines, serotonin and histamine contents, and some elements of their metabolisms. Azin2 hypomorphic BMMCs did not show major mast cell phenotypic alterations as judged by morphology and specific mast cell proteases. However, compared to wild-type controls, these cells showed reduced spermidine and spermine levels, and diminished growth rate. Serotonin levels were also reduced, whereas histamine levels tended to increase. Accordingly, tryptophan hydroxylase-1 (TPH1; the key enzyme for serotonin biosynthesis) mRNA expression and protein levels were reduced, whereas histidine decarboxylase (the enzyme responsible for histamine biosynthesis) enzymatic activity was increased. Furthermore, microphtalmia-associated transcription factor, an element involved in the regulation of Tph1 expression, was reduced. Taken together, our results show, for the first time, an element of polyamine metabolism -AZIN2-, so far described as exclusively devoted to the control of polyamine concentrations, involved in regulating the biosynthesis and content of other amines like serotonin and histamine.
Polyamines and abiotic stress in plants: a complex relationship1
Minocha, Rakesh; Majumdar, Rajtilak; Minocha, Subhash C.
2014-01-01
The physiological relationship between abiotic stress in plants and polyamines was reported more than 40 years ago. Ever since there has been a debate as to whether increased polyamines protect plants against abiotic stress (e.g., due to their ability to deal with oxidative radicals) or cause damage to them (perhaps due to hydrogen peroxide produced by their catabolism). The observation that cellular polyamines are typically elevated in plants under both short-term as well as long-term abiotic stress conditions is consistent with the possibility of their dual effects, i.e., being protectors from as well as perpetrators of stress damage to the cells. The observed increase in tolerance of plants to abiotic stress when their cellular contents are elevated by either exogenous treatment with polyamines or through genetic engineering with genes encoding polyamine biosynthetic enzymes is indicative of a protective role for them. However, through their catabolic production of hydrogen peroxide and acrolein, both strong oxidizers, they can potentially be the cause of cellular harm during stress. In fact, somewhat enigmatic but strong positive relationship between abiotic stress and foliar polyamines has been proposed as a potential biochemical marker of persistent environmental stress in forest trees in which phenotypic symptoms of stress are not yet visible. Such markers may help forewarn forest managers to undertake amelioration strategies before the appearance of visual symptoms of stress and damage at which stage it is often too late for implementing strategies for stress remediation and reversal of damage. This review provides a comprehensive and critical evaluation of the published literature on interactions between abiotic stress and polyamines in plants, and examines the experimental strategies used to understand the functional significance of this relationship with the aim of improving plant productivity, especially under conditions of abiotic stress. PMID:24847338
Lower polyamine levels in breast milk of obese mothers compared to mothers with normal body weight.
Ali, M Atiya; Strandvik, B; Palme-Kilander, C; Yngve, A
2013-07-01
Obesity is associated with risks for mother and infant, and the mothers' dietary habits influence breast milk composition. Polyamines are secreted in breast milk and are essential for the regulation of intestinal and immune function in newborns and infants. The present study aimed to investigate the level of polyamines in human milk obtained from obese and normal weight mothers at different times of lactation. Breast milk from 50 mothers was obtained at day 3, and at 1 and 2 months after delivery. The mothers had normal body weight [body mass index (BMI) < 25 kg m(-2) ] or were obese (BMI > 30 kg/m(2) ). A subgroup of obese mothers participated in a weight reduction programme during pregnancy. Polyamines were analysed using high-performance liquid chromatography. The total polyamine content was significantly lower at all times in breast milk from obese mothers compared to milk from controls. Spermine levels did not differ between groups at any time in contrast to the levels of putrescine and spermidine. Putrescine concentrations were highest on day 3 and spermidine and spermine were highest at 1 month of lactation. The obese mothers, who received dietary advice during pregnancy based on the Nordic Nutrition Recommendations, had higher concentrations of putrescine and spermidine in their milk than the obese mothers without any intervention. Polyamine concentrations were lower in breast milk from obese mothers compared to mothers with a normal weight. General dietary intervention in obese mothers increased the polyamine levels, suggesting that the low levels in obesity were at least partly associated with food habits. However, the consistency of spermine suggests a special metabolic function of this polyamine. © 2013 The Authors Journal of Human Nutrition and Dietetics © 2013 The British Dietetic Association Ltd.
Uma Maheswar Rao, J L; Satyanarayana, T
2004-01-01
Effect of polyamines and their biosynthesis inhibitors on the production of hyperthermostable and Ca2+ -independent alpha-amylase by Geobacillus thermoleovorans MTCC 4220. The alpha-amylase was produced in starch-yeast extract-tryptone (SYT) broth with different polyamines (PA) and polyamine biosynthesis inhibitors, methylglyoxal-bis-guanylhydrazone (MGBG) and cyclohexylammonium sulphate (CHA) at 70 degrees C. The bacterial pellets were obtained after growing G. thermoleovorans at different temperatures, and used in determining total PA. The cell-free culture filtrates were used in alpha-amylase assays. During growth, total polyamines in biomass increased till 2 h, and thereafter, decreased gradually. The total polyamine content was very high in the biomass cultivated at 55 degrees C when compared with that of higher temperatures. Enzyme titre enhanced up to 70 degrees C, and thereafter declined. Extracellular enzyme and protein levels declined in the presence of exogenously added PA. The intracellular enzyme titres, however, were higher in putrescine (put) and spermidine (spd) than in spermine (spm). Polyamine biosynthesis inhibitor, MGBG enhanced secretion of alpha-amylase in a laboratory fermentor as well as shake flasks, although CHA did not affect it. The intracellular accumulation of put in the presence of MGBG appeared to enhance synthesis and secretion of alpha-amylase. Extracellular enzyme and protein levels were low in the presence of exogenously added PA, but their intracellular levels, however, were higher in put and spd than in spm. A substantial increase in the synthesis and secretion of alpha-amylase was attained in G. thermoleovorans in the presence of polyamine biosynthesis inhibitor MGBG.
Sudhakar, Chinta; Veeranagamallaiah, Gounipalli; Nareshkumar, Ambekar; Sudhakarbabu, Owku; Sivakumar, M; Pandurangaiah, Merum; Kiranmai, K; Lokesh, U
2015-01-01
Polyamines can regulate the expression of antioxidant enzymes and impart plants tolerance to abiotic stresses. A comparative analysis of polyamines, their biosynthetic enzymes at kinetic and at transcriptional level, and their role in regulating the induction of antioxidant defense enzymes under salt stress condition in two foxtail millet (Setaria italica L.) cultivars, namely Prasad, a salt-tolerant, and Lepakshi, a salt-sensitive cultivar was conducted. Salt stress resulted in elevation of free polyamines due to increase in the activity of spermidine synthase and S-adenosyl methionine decarboxylase enzymes in cultivar Prasad compared to cultivar Lepakshi under different levels of NaCl stress. These enzyme activities were further confirmed at the transcript level via qRT-PCR analysis. The cultivar Prasad showed a greater decrease in diamine oxidase and polyamine oxidase activity, which results in the accumulation of polyamine pools over cultivar Lepakshi. Generation of free radicals, such as O 2 (·-) and H2O2, was also analyzed quantitatively. A significant increase in O 2 (·-) and H2O2 in the cultivar Lepakshi compared with cultivar Prasad was recorded in overall pool sizes. Further, histochemical staining showed lesser accumulation of O 2 (·-) and of H2O2 in the leaves of cultivar Prasad than cultivar Lepakshi. Our results also suggest the ability of polyamine oxidation in regulating the induction of antioxidative defense enzymes, which involve in the elimination of toxic levels of O 2 (·-) and H2O2, such as Mn-superoxide dismutase, catalase and ascorbate peroxidase. The contribution of polyamines in modulating antioxidative defense mechanism in NaCl stress tolerance is discussed.
Histone deacetylase 10 structure and molecular function as a polyamine deacetylase
NASA Astrophysics Data System (ADS)
Hai, Yang; Shinsky, Stephen A.; Porter, Nicholas J.; Christianson, David W.
2017-05-01
Cationic polyamines such as spermidine and spermine are critical in all forms of life, as they regulate the function of biological macromolecules. Intracellular polyamine metabolism is regulated by reversible acetylation and dysregulated polyamine metabolism is associated with neoplastic diseases such as colon cancer, prostate cancer and neuroblastoma. Here we report that histone deacetylase 10 (HDAC10) is a robust polyamine deacetylase, using recombinant enzymes from Homo sapiens (human) and Danio rerio (zebrafish). The 2.85 Å-resolution crystal structure of zebrafish HDAC10 complexed with a transition-state analogue inhibitor reveals that a glutamate gatekeeper and a sterically constricted active site confer specificity for N8-acetylspermidine hydrolysis and disfavour acetyllysine hydrolysis. Both HDAC10 and spermidine are known to promote cellular survival through autophagy. Accordingly, this work sets a foundation for studying the chemical biology of autophagy through the structure-based design of inhibitors that may also serve as new leads for cancer chemotherapy.
Design and multi-step synthesis of chalcone-polyamine conjugates as potent antiproliferative agents.
Rioux, Benjamin; Pouget, Christelle; Fidanzi-Dugas, Chloë; Gamond, Aurélie; Laurent, Aurélie; Semaan, Josiane; Pinon, Aline; Champavier, Yves; Léger, David Y; Liagre, Bertrand; Duroux, Jean-Luc; Fagnère, Catherine; Sol, Vincent
2017-09-15
The aim of this study is to synthesize chalcone-polyamine conjugates in order to enhance bioavailability and selectivity of chalcone core towards cancer cells, using polyamine-based vectors. 3-hydroxy-3',4,4',5'-tetramethoxychalcone (1) and 3',4,4',5'-tetramethoxychalcone (2) were selected as parent chalcones since they were found to be efficient anti-proliferative agents on various cancer cells. A series of ten chalcone-polyamine conjugates was obtained by reacting carboxychalcones with different polyamine tails. Chalcones 1 and 2 showed a strong cytotoxic activity against two prostatic cancer (PC-3 and DU-145) and two colorectal cancer (HT-29 and HCT-116) cell lines. Then, chalcone-spermine conjugates 7d and 8d were shown to be the most active of the series and could be considered as promising compounds for colon and prostatic cancer adjuvant therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.
Zurková, E; Drobník, J; Kálal, J; Svec, F; Tyrácková, V; Vojtísek, V; Zeman, R
1983-09-01
Whole cells of Escherichia coli containing the enzyme penicillinamidohydrolase EC 3.5.1.11 were immobilized on the surface of modified macroporous copolymers of glycidylmethacrylate with ethylenedimethacrylate and of copolymers of methacrylaldehyde (MA) with divinylbenzene (DVB) by means of glutaraldehyde. These polymeric carriers were modified before cell binding by using ammonia or polyamines, especially ethylenediamine and hexamethylenediamine (HMDA). The highest specific activity and the largest yield in cell immobilization were achieved with the macroporous copolymer of MA and DVB modified with HMDA. The material thus obtained was used in repeated conversions of benzylpenicillin to 6-aminopenicillanic acid in a stirred batch reactor.
VLBI2010 Receiver Back End Comparison
NASA Technical Reports Server (NTRS)
Petrachenko, Bill
2013-01-01
VLBI2010 requires a receiver back-end to convert analog RF signals from the receiver front end into channelized digital data streams to be recorded or transmitted electronically. The back end functions are typically performed in two steps: conversion of analog RF inputs into IF bands (see Table 2), and conversion of IF bands into channelized digital data streams (see Tables 1a, 1b and 1c). The latter IF systems are now completely digital and generically referred to as digital back ends (DBEs). In Table 2 two RF conversion systems are compared, and in Tables 1a, 1b, and 1c nine DBE systems are compared. Since DBE designs are advancing rapidly, the data in these tables are only guaranteed to be current near the update date of this document.
Polyamines and inorganic ions extracted from woody tissues by freeze-thawing
Rakesh Minocha; Walter C. Shortle
1994-01-01
A simple and fast method for extraction of major inorganic ions (Ca, Mg, Mn, K, and P) and cellular polyamines from small quantities of wood and woody plant tissues is described. The method involves repeated freezing and thawing of samples instead of homogenization or wet ash digestion. The efficiency of extraction of both polyamines and inorganic ions by these methods...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (PMN...
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (PMN...
Role of polyamines in DNA synthesis of Catharanthus roseus cells grown in suspension culture
Rakesh Minocha; Subhash C. Minocha; Atsushi Komamine; Walter C. Shortle
1990-01-01
The requirement for polyamines in the proliferation of cells was first demonstrated in bacteria (3). While significant progress has been made in this field using animal cell cultures, only preliminary studies have been reported with plant tissues. Serafini-Fracassini et al. (9) showed a marked increase in polyamine synthesis early during the G 1 phase, concomitant with...
USDA-ARS?s Scientific Manuscript database
Tuber wound-healing processes are complex, and the associated regulation and modulation of these processes are poorly understood. Polyamines (PA) have been shown to be involved in modulating a variety of responses to biotic and abiotic plant stresses and have been suggested to be involved in tuber ...
Polyamine Analogues as Novel Anti-HER Family Agents in Human Breast Cancer
2008-09-01
Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Elevated levels of all three naturally occurring polyamines, spermine, spermidine ...11 Appendices����������������������������� N/A 4 INTRODUCTION The polyamines, spermine, spermidine and
Pavlov, V; Lin, P Kong Thoo; Rodilla, V
2002-04-01
The novel polyamine derivatives sulphonamido oxa-spermine (oxa-Spm) and sulphonamido oxa-spermidine (oxa-Spd) exhibited rapid cytotoxic action towards MCF-7 human breast cancer cells with IC50 values of 4.35 and 6.47 pM, respectively, after 24-h drug exposure. Neither compound is a substrate of serum amine oxidase. Both oxa-Spm and oxa-Spd caused cell shrinkage, as determined by phase-contrast microscopy. After incubation with 10 microM of either compound for 8 h, the cells underwent chromatin condensation and nuclear fragmentation. However, no clear DNA ladder was obtained by electrophoresis. The sulphonamido oxa-polyamine derivatives and especially oxa-Spd enhanced the activity of polyamine oxidase (PAO), an enzyme capable of oxidising N1-acetylated spermine and spermidine to spermidine and putrescine, respectively, generating cytotoxic H2O2 and 3-acetamidopropanal as by-products. The intracellular polyamine content was only marginally reduced in response to drug treatment. In conclusion, our data show that these novel sulphonamido oxa-polyamine derivatives possess high cytotoxic activity against MCF-7 cells and indicate that induction of PAO may mediate their cytotoxicity via apoptosis.
Wang, Qian; Wang, Yixiang; Liu, Ran; Yan, Xu; Li, Yujiao; Fu, Hui; Bi, Kaishun; Li, Qing
2013-02-01
A simple and sensitive method for the simultaneous determination of plasma concentrations of five polyamines in normal and Hepatoma-22 mice, and mice treated with Mylabris and Acanthopanax senticosus was developed by HPLC-ESI-MS. Male Kunming mice were divided into nine groups, a control group (inoculation without treatment), a positive group (Cyclophosphamide), treatment groups [Mylabris (4, 8, 16 mg/kg), Acanthopanax senticosus (6, 12, 24 g/kg)] and a normal group (without inoculation). Twenty-four hours after the last administration, plasma samples were collected. The derived polyamines were separated on a C(18) column by a gradient elution using methanol-water with excellent linearity within the range from 2.5 to 1000 ng/mL. Polyamines were confirmed as useful biochemical markers of hepatoma. The differences in anti-cancer therapeutic efficacy between Mylabris and Acanthopanax senticosus might contribute to the variability of polyamine levels in vivo. This HPLC-ESI-MS method was successfully applied to investigate the relationship between polyamines and cancer in mice and might be a useful method to test the activity of potential anti-tumor drugs. Copyright © 2012 John Wiley & Sons, Ltd.
Breitbeil, Fred; Kaur, Navneet; Delcros, Jean-Guy; Martin, Bénédicte; Abboud, Khalil A; Phanstiel, Otto
2006-04-20
Preferred conformers generated from motuporamine and anthracene-polyamine derivatives provided insight into the shapes associated with polyamine transporter (PAT) recognition and potentially dihydromotuporamine C (4a) bioactivity. Molecular modeling revealed that N(1)-(anthracen-9-ylmethyl)-3,3-triamine (6a), N(1)-(anthracen-9-ylmethyl)-4,4-triamine (6b), N(1)-(anthracen-9-ylmethyl)-N(1)-ethyl-3,3-triamine (7a), N(1)-(anthracen-9-ylmethyl)-N(1)-ethyl-4,4-triamine (7b), and 4a all preferred a hoe motif. This hoe shape was defined by the all-anti polyamine shaft extending above the relatively flat, appended ring system. The hoe geometry was also inferred by the (1)H NMR spectrum of the free amine of 7a (CDCl(3)), which showed a strong shielding effect of the anthracene ring on the chemical shifts associated with the appended polyamine chain. This shielding effect was found to be independent over a broad concentration range of 7a, which also supported an intramolecular phenomenon. The degree of substitution at the N(1)-position seems to be an important determinant of both the molecular shape preferences and biological activity of anthracenylmethyl-polyamine conjugates.
Polyamines and plant stress - Activation of putrescine biosynthesis by osmotic shock
NASA Technical Reports Server (NTRS)
Flores, H. E.; Galston, A. W.
1982-01-01
The putrescine content of oat leaf cells and protoplasts increases up to 60-fold within 6 hours of exposure to osmotic stress (0.4 to 0.6 molar sorbitol). Barley, corn, wheat, and wild oat leaves show a similar response. Increased arginine decarboxylase activity parallels the rise in putrescine, whereas ornithine decarboxylase remains unchanged. DL-alpha-Difluoromethylarginine, a specific irreversible inhibitor of arginine decarboxylase, prevents the stress-induced rise in increase in arginine decarboxylase activity and putrescine synthesis, indicating the preferential activation of this pathway.
Polyamines and abiotic stress in plants: a complex relationship Frontiers in Plant Science
Rakesh Minocha; Rajtilak Majumdar; Subhash C. Minocha
2014-01-01
The physiological relationship between abiotic stress in plants and polyamines was reported more than 40 years ago. Ever since there has been a debate as to whether increased polyamines protect plants against abiotic stress (e.g., due to their ability to deal with oxidative radicals) or cause damage to them (perhaps due to hydrogen peroxide produced by their catabolism...
Michelle J. Serapiglia; Rakesh Minocha; Subhash C. Minocha
2008-01-01
We analyzed effects of nitrogen availability and form on growth rates, concentrations of polyamines and inorganic ions and glutamine synthetase activity in in-vitro-cultured red spruce (Picea rubens Sarg.) cells. Growth rates, concentrations of polyamines and glutamine synthetase activity declined when either the amount of nitrate or the total amount...
Gulshan, Mst Ara; Matsumura, Shigeyoshi; Higuchi, Tsunehiko; Umezawa, Naoki; Ikawa, Yoshiya
2018-04-26
Polyamines are a promising class of molecules that can modulate RNA enzyme activities. To analyze the effects of the number of amine moieties systematically, we employed four polyamines sharing dimethylene units to connect amine moieties. As a model RNA enzyme, we used a structurally unstable group I ribozyme, which was activated most and least efficiently by tetraethylenepentamine and diethylenetriamine respectively.
Rakesh Minocha; Walter C. Shortle; Stephanie L. Long; Subhash C. Minocha
1994-01-01
A fast and reliable method for the extraction of cellular polyamines and major inorganic ions (Ca, Mg, Mn, K, and P) from several plant tissues is described. The method involves repeated freezing and thawing of samples instead of homogenization. The efficiency of extraction of both the polyamines and inorganic ions by these two methods was compared for 10 different...
Jänne, Juhani; Hovi, Tapani; Hölttä, Erkki
1979-01-01
1. The activation of human peripheral blood lymphocytes by phytohaemagglutinin in vitro was accompanied by striking increases in the concentrations of the natural polyamines putrescine, spermidine and spermine. 2. The enhanced accumulation of polyamines could be almost totally abolished by dl-α-difluoromethylornithine, a newly discovered irreversible inhibitor of l-ornithine decarboxylase (EC 4.1.1.17), or by methylglyoxal bis(guanylhydrazone) {1,1′-[(methylethanediylidene)dinitrilo]diguanidine}, an inhibitor of S-adenosyl-l-methionine decarboxylase (EC 4.1.1.50). The inhibition of polyamine accumulation was associated with a marked suppression of DNA synthesis, which was partially or totally reversed by low concentrations of exogenous putrescine, spermidine, spermine and cadaverine and by higher concentrations of 1,3-diaminopropane. 3. In contrast with some earlier studies, we found that methylglyoxal bis(guanylhydrazone), at concentrations that were sufficient to prevent polyamine accumulation, also caused a clear inhibition of protein synthesis in the activated lymphocytes. Similar results were obtained with difluoromethylornithine. The decrease in protein synthesis caused by both compounds preceded the impairment of DNA synthesis. The inhibition of protein synthesis by difluoromethylornithine was fully reversed by exogenous putrescine, spermidine and spermine, and that caused by methylglyoxal bis(guanylhydrazone) by spermidine and spermine. In further support of the idea that the inhibition of protein synthesis by these compounds was related to the polyamine depletion, we found that difluoromethylornithine caused a dose-dependent decrease in the incorporation of [14C]leucine into lymphocyte proteins which closely correlated with the decreased concentrations of cellular spermidine. 4. Difluoromethylornithine and methylglyoxal bis(guanylhydrazone) also elicited a variable depression in the incorporation of [3H]uridine and [14C]adenine into total RNA. The apparent turnover of lymphocyte RNA remained essentially unchanged in spite of severe polyamine depletion brought about by difluoromethylornithine. 5. The present results, as well as confirming the anti-proliferative action of the inhibitors of polyamine biosynthesis, suggest that polyamine depletion may interfere with reactions at different levels of gene expression. PMID:435270
Hölttä, E; Jänne, J; Hovi, T
1979-01-15
1. The activation of human peripheral blood lymphocytes by phytohaemagglutinin in vitro was accompanied by striking increases in the concentrations of the natural polyamines putrescine, spermidine and spermine. 2. The enhanced accumulation of polyamines could be almost totally abolished by dl-alpha-difluoromethylornithine, a newly discovered irreversible inhibitor of l-ornithine decarboxylase (EC 4.1.1.17), or by methylglyoxal bis(guanylhydrazone) {1,1'-[(methylethanediylidene)dinitrilo]diguanidine}, an inhibitor of S-adenosyl-l-methionine decarboxylase (EC 4.1.1.50). The inhibition of polyamine accumulation was associated with a marked suppression of DNA synthesis, which was partially or totally reversed by low concentrations of exogenous putrescine, spermidine, spermine and cadaverine and by higher concentrations of 1,3-diaminopropane. 3. In contrast with some earlier studies, we found that methylglyoxal bis(guanylhydrazone), at concentrations that were sufficient to prevent polyamine accumulation, also caused a clear inhibition of protein synthesis in the activated lymphocytes. Similar results were obtained with difluoromethylornithine. The decrease in protein synthesis caused by both compounds preceded the impairment of DNA synthesis. The inhibition of protein synthesis by difluoromethylornithine was fully reversed by exogenous putrescine, spermidine and spermine, and that caused by methylglyoxal bis(guanylhydrazone) by spermidine and spermine. In further support of the idea that the inhibition of protein synthesis by these compounds was related to the polyamine depletion, we found that difluoromethylornithine caused a dose-dependent decrease in the incorporation of [(14)C]leucine into lymphocyte proteins which closely correlated with the decreased concentrations of cellular spermidine. 4. Difluoromethylornithine and methylglyoxal bis(guanylhydrazone) also elicited a variable depression in the incorporation of [(3)H]uridine and [(14)C]adenine into total RNA. The apparent turnover of lymphocyte RNA remained essentially unchanged in spite of severe polyamine depletion brought about by difluoromethylornithine. 5. The present results, as well as confirming the anti-proliferative action of the inhibitors of polyamine biosynthesis, suggest that polyamine depletion may interfere with reactions at different levels of gene expression.
Alhonen-Hongisto, L; Seppänen, P; Jänne, J
1980-01-01
Inhibition of polyamine synthesis by alpha-difluoromethylornithine in cultured Ehrlich ascites-carcinoma cells rapidly enhanced the uptake of exogenous putrescine, spermidine and spermine from the culture medium. In tumour cells exposed to the drug for 2 days, the intracellular concentration of spermidine was decreased to less than 10% of that found in untreated cells. However, the strikingly stimulated transport system brought the concentration of spermidine to the control values in less than 2h after supplementation of the cells with micromolar concentrations of the polyamine. In the absence of polyamine deprivation, tumour cells did not accumulate extracellular polyamines to any appreciable extent. Ascites-tumour cells deprived of putrescine and spermidine likewise concentrated methylglyoxal bis(guanylhydrazone) [1,1'-[methylethanedylidine)dinitrilo]diguanidine] at a greatly enhanced rate. A previous "priming of tumour cells with difluoromethylornithine followed by an exposure of the cells to methylglyoxal bis(guanylhydrazone) resulted in a marked and rapid anti-proliferative effect. PMID:6786285
Hudec, Jozef; Bakos, Dusan; Mravec, Dusan; Kobida, L'ubomír; Burdová, Maria; Turianica, Ivan; Hlusek, Jaroslav
2006-05-17
The total contents of anthocyanins, flavonoids, and phenolics in 60 samples of black chokeberries (Aronia melanocarpa), after treating with catabolites of polyamine biosynthesis (KPAb) and ornithine decarboxylase inhibitor, were analyzed spectrophotometrically, and quercetin and free polyamine contents were analyzed by RP-HPLC with UV detection. The average total contents of the individual substances and phenolic subgroups in control berries were as follows (mg x kg(-1)): anthocyanines, 6408; flavonoids, 664; phenolics, 37,600; quercetin, 349. KPAb decreased total contents of anthocyanines and phenolics only slightly but significantly increased the content of flavonoids. This caused an important change in the abundance of flavonoids in the pigment complex. The absolute content of quercetin was increased, but its ratio to flavonoids content was decreased. Ornithine decarboxylase inhibitor had a markedly different effect as it significantly increased total content of anthocyanins and total phenolics, inhibited the total content of free polyamines, and stimulated the processes of saccharides transformation to phenolic pigments.
Agmatine is transported into liver mitochondria by a specific electrophoretic mechanism
Salvi, Mauro; Battaglia, Valentina; Mancon, Mario; Colombatto, Sebastiano; Cravanzola, Carlo; Calheiros, Rita; Marques, Maria P. M.; Grillo, Maria A.; Toninello, Antonio
2006-01-01
Agmatine, a divalent diamine with two positive charges at physiological pH, is transported into the matrix of liver mitochondria by an energy-dependent mechanism the driving force of which is ΔΨ (electrical membrane potential). Although this process showed strict electrophoretic behaviour, qualitatively similar to that of polyamines, agmatine is most probably transported by a specific uniporter. Shared transport with polyamines by means of their transporter is excluded, as divalent putrescine and cadaverine are ineffective in inhibiting agmatine uptake. Indeed, the use of the electroneutral transporter of basic amino acids can also be discarded as ornithine, arginine and lysine are completely ineffective at inducing the inhibition of agmatine uptake. The involvement of the monoamine transporter or the existence of a leak pathway are also unlikely. Flux-voltage analysis and the determination of activation enthalpy, which is dependent upon the valence of agmatine, are consistent with the hypothesis that the mitochondrial agmatine transporter is a channel or a single-binding centre-gated pore. The transport of agmatine was non-competitively inhibited by propargylamines, in particular clorgilyne, that are known to be inhibitors of MAO (monoamine oxidase). However, agmatine is normally transported in mitoplasts, thus excluding the involvement of MAO in this process. The I2 imidazoline receptor, which binds agmatine to the mitochondrial membrane, can also be excluded as a possible transporter since its inhibitor, idazoxan, was ineffective at inducing the inhibition of agmatine uptake. Scatchard analysis of membrane binding revealed two types of binding site, S1 and S2, both with mono-co-ordination, and exhibiting high-capacity and low-affinity binding for agmatine compared with polyamines. Agmatine transport in liver mitochondria may be of physiological importance as an indirect regulatory system of cytochrome c oxidase activity and as an inducer mechanism of mitochondrial-mediated apoptosis. PMID:16509824
Madka, Venkateshwar; Mohammed, Altaf; Li, Qian; Zhang, Yuting; Kumar, Gaurav; Lightfoot, Stan; Wu, Xueru; Steele, Vernon; Kopelovich, Levy; Rao, Chinthalapally V
2015-01-01
Mutations of the tumor suppressor p53 and elevated levels of polyamines are known to play key roles in urothelial tumorigenesis. We investigated the inhibition of polyamines biosynthesis and the restoration of p53 signaling as a possible means of preventing muscle invasive urothelial tumors using DFMO, an ODC-inhibiting agent, and CP-31398 (CP), a p53 stabilizing agent. Transgenic UPII-SV40T male mice at 6weeks age (n=15/group) were fed control diet (AIN-76A) or experimental diets containing DFMO (1000 and 2000 ppm) or 150 ppm CP or both. At 40 weeks of age, all mice were euthanized and urinary bladders were evaluated to determine tumor weight and histopathology. Low-dose DFMO had a moderate significant inhibitory effect on tumor growth (38%, P<0.02) and tumor invasion (23%). High-dose DFMO had a 47% tumor inhibition (P<0.0001) and 40% inhibition tumor invasion. There was no significant difference between 1000 and 2000 ppm doses of DFMO (P>0.05). CP at 150 ppm alone had a strong inhibitory effect on tumor growth by 80% (P<0.0001); however, no effect on tumor invasion was observed. Interestingly, the combination of DFMO (1000 ppm) and CP (150 ppm) led to significant decrease in tumor weight (70%, P<0.0001) and tumor invasion (62.5%; P<0.005). Molecular analysis of the urothelial tumors suggested a modulation of polyamine biosynthesis, proliferation, cell cycle regulators resulting from the use of these agents. These results suggest that targeting two or more pathways could be an effective approach for chemoprevention. A combination of CP and DFMO appears to be a promising strategy for urothelial TCC prevention.
Liu, Hua-Ying; Xiao, Lang-Tao; Lu, Xu-Dong; Hu, Jia-Jin; Wu, Shun; He, Chang-Zheng; Deng, Xiu-Xin
2005-06-01
Somatic embryogenetic capability and changes in polyamine level and their relationship were analyzed using the long-term (8 years) subcultured calli of Citrus sinensis Osb. cv. Valencia as materials. The results showed that endogenous polyamine contents in embryogenic calli were higher than those in non-embryogenic calli, and the embryogenetic capability was positively correlated to the levels of endogenous polyamines. When the calli were transferred to a differentiation medium, the putrescine content rapidly increased and reached a peak, then fell gradually. Applying exogenous putrescine raised the embryogenesis frequency and endogenous putrescine level. It indicated that increase in putrescine content at early stage of differentiation promoted embryogenesis. With the development of somatic embryo, spermidine content reached its the highest level at globular embryo stage, spermine content rose and reached a peak at a later stage of globular embryo development. Furthermore, changes of the putrescine, spermidine and spermine contents during somatic embryogenesis were similar in Valencia calli which had different ploidy levels, but their contents decreased following the increasing of ploidy level. Changes in arginine decarboxylase activity were positively correlated to the polyamine levels, which suggest that the later is a key factor in regulating the polyamine levels during somatic embryogenesis in citrus plants.
Polyamine-Blocking Therapy Reverses Immunosuppression in the Tumor Microenvironment
Hayes, Candace S.; Shicora, Allyson C.; Keough, Martin P.; Snook, Adam E.; Burns, Mark R.; Gilmour, Susan K.
2014-01-01
Correcting T cell immunosuppression may unleash powerful antitumor responses, however, knowledge about the mechanisms and modifiers that may be targeted to improve therapy remains incomplete. Here we report that polyamine elevation in cancer, a common metabolic aberration in aggressive lesions, contributes significantly to tumor immunosuppression and that a polyamine depletion strategy can exert antitumor effects that may also promote immunity. A polyamine-blocking therapy (PBT) that combines the well-characterized ornithine decarboxylase (ODC) inhibitor difluoromethylornithine (DFMO) with AMXT1501, a novel inhibitor of the polyamine transport system, blocked tumor growth in immunocompetent mice but not in athymic nude mice lacking T cells. PBT had little effect on the proliferation of epithelial tumor cells but it increased the number of apoptotic cells. Analysis of CD45+ tumor immune infiltrates revealed that PBT decreased levels of Gr-1+CD11b+ myeloid suppressor cells and increased CD3+ T cells. Strikingly, in a model of neoadjuvant therapy, mice administered PBT one week before surgical resection of engrafted mammary tumors exhibited resistance to subsequent tumor re-challenge. Collectively, our results indicate that therapies targeting polyamine metabolism do not act exclusively as anti-proliferative agents, but also act strongly to prevent immune escape by the tumor. PBT may offer a general approach to heighten immune responses in cancer. PMID:24778323
Krammer, Eva-Maria; Ghaddar, Kassem; André, Bruno
2016-01-01
Commensal and pathogenic enteric bacteria have developed several systems to adapt to proton leakage into the cytoplasm resulting from extreme acidic conditions. One such system involves arginine uptake followed by export of the decarboxylated product agmatine, carried out by the arginine/agmatine antiporter (AdiC), which thus works as a virtual proton pump. Here, using classical and targeted molecular dynamics, we investigated at the atomic level the mechanism of arginine transport through AdiC of E. coli. Overall, our MD simulation data clearly demonstrate that global rearrangements of several transmembrane segments are necessary but not sufficient for achieving transitions between structural states along the arginine translocation pathway. In particular, local structural changes, namely rotameric conversions of two aromatic residues, are needed to regulate access to both the outward- and inward-facing states. Our simulations have also enabled identification of a few residues, overwhelmingly aromatic, which are essential to guiding arginine in the course of its translocation. Most of them belong to gating elements whose coordinated motions contribute to the alternating access mechanism. Their conservation in all known E. coli acid resistance antiporters suggests that the transport mechanisms of these systems share common features. Last but not least, knowledge of the functional properties of AdiC can advance our understanding of the members of the amino acid-carbocation-polyamine superfamily, notably in eukaryotic cells. PMID:27482712
Methanol-based cadaverine production by genetically engineered Bacillus methanolicus strains.
Naerdal, Ingemar; Pfeifenschneider, Johannes; Brautaset, Trygve; Wendisch, Volker F
2015-03-01
Methanol is regarded as an attractive substrate for biotechnological production of value-added bulk products, such as amino acids and polyamines. In the present study, the methylotrophic and thermophilic bacterium Bacillus methanolicus was engineered into a microbial cell factory for the production of the platform chemical 1,5-diaminopentane (cadaverine) from methanol. This was achieved by the heterologous expression of the Escherichia coli genes cadA and ldcC encoding two different lysine decarboxylase enzymes, and by increasing the overall L-lysine production levels in this host. Both CadA and LdcC were functional in B. methanolicus cultivated at 50°C and expression of cadA resulted in cadaverine production levels up to 500 mg l(-1) during shake flask conditions. A volume-corrected concentration of 11.3 g l(-1) of cadaverine was obtained by high-cell density fed-batch methanol fermentation. Our results demonstrated that efficient conversion of L-lysine into cadaverine presumably has severe effects on feedback regulation of the L-lysine biosynthetic pathway in B. methanolicus. By also investigating the cadaverine tolerance level, B. methanolicus proved to be an exciting alternative host and comparable to the well-known bacterial hosts E. coli and Corynebacterium glutamicum. This study represents the first demonstration of microbial production of cadaverine from methanol. © 2015 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.
Methanol-based cadaverine production by genetically engineered Bacillus methanolicus strains
Nærdal, Ingemar; Pfeifenschneider, Johannes; Brautaset, Trygve; Wendisch, Volker F
2015-01-01
Methanol is regarded as an attractive substrate for biotechnological production of value-added bulk products, such as amino acids and polyamines. In the present study, the methylotrophic and thermophilic bacterium Bacillus methanolicus was engineered into a microbial cell factory for the production of the platform chemical 1,5-diaminopentane (cadaverine) from methanol. This was achieved by the heterologous expression of the Escherichia coli genes cadA and ldcC encoding two different lysine decarboxylase enzymes, and by increasing the overall L-lysine production levels in this host. Both CadA and LdcC were functional in B. methanolicus cultivated at 50°C and expression of cadA resulted in cadaverine production levels up to 500 mg l−1 during shake flask conditions. A volume-corrected concentration of 11.3 g l−1 of cadaverine was obtained by high-cell density fed-batch methanol fermentation. Our results demonstrated that efficient conversion of L-lysine into cadaverine presumably has severe effects on feedback regulation of the L-lysine biosynthetic pathway in B. methanolicus. By also investigating the cadaverine tolerance level, B. methanolicus proved to be an exciting alternative host and comparable to the well-known bacterial hosts E. coli and Corynebacterium glutamicum. This study represents the first demonstration of microbial production of cadaverine from methanol. PMID:25644214
Xie, Ying; Murray-Stewart, Tracy; Wang, Yazhe; Yu, Fei; Li, Jing; Marton, Laurence J; Casero, Robert A; Oupický, David
2017-01-28
Combination of anticancer drugs with therapeutic microRNA (miRNA) has emerged as a promising anticancer strategy. However, the promise is hampered by a lack of desirable delivery systems. We report on the development of self-immolative nanoparticles capable of simultaneously delivering miR-34a mimic and targeting dysregulated polyamine metabolism in cancer. The nanoparticles were prepared from a biodegradable polycationic prodrug, named DSS-BEN, which was synthesized from a polyamine analog N 1 ,N 11 -bisethylnorspermine (BENSpm). The nanoparticles were selectively disassembled in the cytoplasm where they released miRNA. Glutathione (GSH)-induced degradation of self-immolative linkers released BENSpm from the DSS-BEN polymers. MiR-34a mimic was effectively delivered to cancer cells as evidenced by upregulation of intracellular miR-34a and downregulation of Bcl-2 as one of the downstream targets of miR-34a. Intracellular BENSpm generated from the degraded nanoparticles induced the expression of rate-limiting enzymes in polyamine catabolism (SMOX, SSAT) and depleted cellular natural polyamines. Simultaneous regulation of polyamine metabolism and miR-34a expression by DSS-BEN/miR-34a not only enhanced cancer cell killing in cultured human colon cancer cells, but also improved antitumor activity in vivo. The reported findings validate the self-immolative nanoparticles as delivery vectors of therapeutic miRNA capable of simultaneously targeting dysregulated polyamine metabolism in cancer, thereby providing an elegant and efficient approach to combination nanomedicines. Copyright © 2016 Elsevier B.V. All rights reserved.
Shen, Yun; Ruan, Qingxia; Chai, Haoxi; Yuan, Yongze; Yang, Wannian; Chen, Junping; Xin, Zhanguo; Shi, Huazhong
2016-12-01
Polyamines involve in gene regulation by interacting with and modulating the functions of various anionic macromolecules such as DNA, RNA and proteins. In this study, we identified an important function of the polyamine transporter LHR1 (LOWER EXPRESSION OF HEAT RESPONSIVE GENE1) in heat-inducible gene expression in Arabidopsis thaliana. The lhr1 mutant was isolated through a forward genetic screening for altered expression of the luciferase reporter gene driven by the promoter from the heat-inducible gene AtHSP18.2. The lhr1 mutant showed reduced induction of the luciferase gene in response to heat stress and was more sensitive to high temperature than the wild type. Map-based cloning identified that the LHR1 gene encodes the polyamine transporter PUT3 (POLYAMINE UPTAKE TRANSPORTER 3) localized in the plasma membrane. The LHR1/PUT3 is required for the uptake of extracellular polyamines and plays an important role in stabilizing the mRNAs of several crucial heat stress responsive genes under high temperature. Genome-wide gene expression analysis using RNA-seq identified an array of differentially expressed genes, among which the transcript levels of some of the heat shock protein genes significantly reduced in response to prolonged heat stress in the lhr1 mutant. Our findings revealed an important heat stress response and tolerance mechanism involving polyamine influx which modulates mRNA stability of heat-inducible genes under heat stress conditions. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.
Pottosin, Igor; Velarde-Buendía, Ana María; Bose, Jayakumar; Fuglsang, Anja T; Shabala, Sergey
2014-06-01
Polyamines regulate a variety of cation and K(+) channels, but their potential effects on cation-transporting ATPases are underexplored. In this work, noninvasive microelectrode ion flux estimation and conventional microelectrode techniques were applied to study the effects of polyamines on Ca(2+) and H(+) transport and membrane potential in pea roots. Externally applied spermine or putrescine (1mM) equally activated eosin yellow (EY)-sensitive Ca(2+) pumping across the root epidermis and caused net H(+) influx or efflux. Proton influx induced by spermine was suppressed by EY, supporting the mechanism in which Ca(2+) pump imports 2 H(+) per each exported Ca(2+). Suppression of the Ca(2+) pump by EY diminished putrescine-induced net H(+) efflux instead of increasing it. Thus, activities of Ca(2+) and H(+) pumps were coupled, likely due to the H(+)-pump inhibition by intracellular Ca(2+). Additionally, spermine but not putrescine caused a direct inhibition of H(+) pumping in isolated plasma membrane vesicles. Spermine, spermidine, and putrescine (1mM) induced membrane depolarization by 70, 50, and 35 mV, respectively. Spermine-induced depolarization was abolished by cation transport blocker Gd(3+), was insensitive to anion channels' blocker niflumate, and was dependent on external Ca(2+). Further analysis showed that uptake of polyamines but not polyamine-induced cationic (K(+)+Ca(2+)+H(+)) fluxes were a main cause of membrane depolarization. Polyamine increase is a common component of plant stress responses. Activation of Ca(2+) efflux by polyamines and contrasting effects of polyamines on net H(+) fluxes and membrane potential can contribute to Ca(2+) signalling and modulate a variety of transport processes across the plasma membrane under stress. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Dunford, Louise J; Sinclair, Kevin D; Kwong, Wing Y; Sturrock, Craig; Clifford, Bethan L; Giles, Tom C; Gardner, David S
2014-11-01
This paper identifies a common nutritional pathway relating maternal through to fetal protein-energy malnutrition (PEM) and compromised fetal kidney development. Thirty-one twin-bearing sheep were fed either a control (n=15) or low-protein diet (n=16, 17 vs. 8.7 g crude protein/MJ metabolizable energy) from d 0 to 65 gestation (term, ∼ 145 d). Effects on the maternal and fetal nutritional environment were characterized by sampling blood and amniotic fluid. Kidney development was characterized by histology, immunohistochemistry, vascular corrosion casts, and molecular biology. PEM had little measureable effect on maternal and fetal macronutrient balance (glucose, total protein, total amino acids, and lactate were unaffected) or on fetal growth. PEM decreased maternal and fetal urea concentration, which blunted fetal ornithine availability and affected fetal hepatic polyamine production. For the first time in a large animal model, we associated these nutritional effects with reduced micro- but not macrovascular development in the fetal kidney. Maternal PEM specifically impacts the fetal ornithine cycle, affecting cellular polyamine metabolism and microvascular development of the fetal kidney, effects that likely underpin programming of kidney development and function by a maternal low protein diet. © FASEB.
Ioannidis, Nikolaos E.; Malliarakis, Dimitris; Torné, Josep M.; Santos, Mireya; Kotzabasis, Kiriakos
2016-01-01
Plastidial transglutaminase is one of the most promising enzymes in chloroplast bioenergetics due to its link with polyamine pathways and the cross talk with signals such as Ca2+ and GTP. Here, we show the effect of the increase of transglutaminase activity in Arabidopsis by using genetic transformation techniques. These lines fulfill their biological cycle normally (normal growth in soil, production of viable seeds) and show a relatively mild increase in transglutaminase activity (127%). These overexpressors of transglutaminase (OE TGase) have an extended stroma thylakoid network (71% higher number of PSIIβ centers), similar chlorophyll content (-4%), higher linear electron flow (+13%), and higher threshold of photoprotection activation (∼100%). On the other hand OE TGase showed a reduced maximum photochemistry of PSII (-6.5%), a smaller antenna per photosystem II (-25%), a lower photoprotective “energization” quenching or qE (-77% at 490 μmol photons m-2 s-1) due to a higher threshold of qE activation and slightly lower light induced proton motive force (-17%). The role of the polyamines and of the transglutaminase in the regulation of chemiosmosis and photoprotection in chloroplasts is discussed. PMID:27242838
Polyamine Analogues as Novel Anti-HER Family Agents in Human Breast Cancer
2007-09-01
Davidson NE, & Casero RA Jr. Spermine oxidase SMO(PAOh1), not N1-acetylpolyamine oxidase PAO, is the primary source of cytotoxic H2O2 in polyamine...Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Elevated levels of all three naturally occurring polyamines, spermine , spermidine and...protein in multiple human breast cancer cell lines. This suppression is both time and dose dependent. A relationship between oligoamine structure , growth
Rakesh Minocha; Stephanie Long; Alison H. Magill; John Aber; William H. McDowell
2000-01-01
Polyamines (putrescine, spermidine, and spermine) are low molecular weight, open-chained, organic polycations which are found in all organisms and have been linked with stress responses in plants. The objectives of our study were to investigate the effects of chronic N additions to pine and hardwood stands at Harvard Forest, Petersham, MA on foliar polyamine and...
Suicide and the Polyamine System
Gross, Jeffrey A.; Turecki, Gustavo
2017-01-01
Suicide is a significant worldwide public health problem. Understanding the neurobiology is important as it can help us to better elucidate underlying etiological factors and provide opportunities for intervention. In recent years, many lines of research have suggested that the polyamine system may be dysregulated in suicidal behaviors. Initial research in animals provided evidence of a dysfunctional polyamine stress response system, while later work using post-mortem human brain tissue has suggested that molecular mechanisms may be at play in the suicide brain. In this review, we will describe the research that suggests the presence of alterations in the polyamine system in mental disorders and behavioral phenotypes, with particular attention to work on suicide. In addition, we will also describe potential avenues for future work. PMID:24040803
Samejima, Keijiro; Otani, Masahiro; Murakami, Yasuko; Oka, Takami; Kasai, Misao; Tsumoto, Hiroki; Kohda, Kohfuku
2007-10-01
A sensitive method for the determination of polyamines in mammalian cells was described using electrospray ionization and time-of-flight mass spectrometer. This method was 50-fold more sensitive than the previous method using ionspray ionization and quadrupole mass spectrometer. The method employed the partial purification and derivatization of polyamines, but allowed a measurement of multiple samples which contained picomol amounts of polyamines. Time required for data acquisition of one sample was approximately 2 min. The method was successfully applied for the determination of reduced spermidine and spermine contents in cultured cells under the inhibition of aminopropyltransferases. In addition, a new proper internal standard was proposed for the tracer experiment using (15)N-labeled polyamines.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tan, Eric; Snowden-Swan, Lesley J.; Talmadge, Michael
This paper presents a comparative techno-economic analysis of five conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with specific focus on pathways utilizing oxygenated intermediates (derived either via thermochemical or biochemical conversion steps). The four emerging pathways of interest are compared with one conventional pathway (Fischer-Tropsch) for the production of the hydrocarbon blendstocks. The processing steps of the four emerging pathways include: biomass-to-syngas via indirect gasification, gas cleanup, conversion of syngas to alcohols/oxygenates, followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation. We show that the emerging pathways via oxygenated intermediatesmore » have the potential to be cost competitive with the conventional Fischer-Tropsch process. The evaluated pathways and the benchmark process generally exhibit similar fuel yields and carbon conversion efficiencies. The resulting minimum fuel selling prices are comparable to the benchmark at approximately $3.60 per gallon-gasoline equivalent, with potential for two new pathways to be more economically competitive. Additionally, the coproduct values can play an important role in the economics of the processes with oxygenated intermediates derived via syngas fermentation. Major cost drivers for the integrated processes are tied to achievable fuel yields and conversion efficiency of the intermediate steps, i.e., the production of oxygenates/alcohols from syngas and the conversion of oxygenates/alcohols to hydrocarbon fuels.« less
12 CFR 708b.301 - Conversion of insurance (State Chartered Credit Union).
Code of Federal Regulations, 2012 CFR
2012-01-01
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12 CFR 708b.301 - Conversion of insurance (State Chartered Credit Union).
Code of Federal Regulations, 2013 CFR
2013-01-01
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12 CFR 708b.301 - Conversion of insurance (State Chartered Credit Union).
Code of Federal Regulations, 2014 CFR
2014-01-01
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Translational development of difluoromethylornithine (DFMO) for the treatment of neuroblastoma
Bassiri, Hamid; Benavides, Adriana; Haber, Michelle; Gilmour, Susan K.; Norris, Murray D.
2015-01-01
Neuroblastoma is a childhood tumor in which MYC oncogenes are commonly activated to drive tumor progression. Survival for children with high-risk neuroblastoma remains poor despite treatment that incorporates high-dose chemotherapy, stem cell support, surgery, radiation therapy and immunotherapy. More effective and less toxic treatments are sought and one approach under clinical development involves re-purposing the anti-protozoan drug difluoromethylornithine (DFMO; Eflornithine) as a neuroblastoma therapeutic. DFMO is an irreversible inhibitor of ornithine decarboxylase (Odc), a MYC target gene, bona fide oncogene, and the rate-limiting enzyme in polyamine synthesis. DFMO is approved for the treatment of Trypanosoma brucei gambiense encephalitis (“African sleeping sickness”) since polyamines are essential for the proliferation of these protozoa. However, polyamines are also critical for mammalian cell proliferation and the finding that MYC coordinately regulates all aspects of polyamine metabolism suggests polyamines may be required to support cancer promotion by MYC. Pre-emptive blockade of polyamine synthesis is sufficient to block tumor initiation in an otherwise fully penetrant transgenic mouse model of neuroblastoma driven by MYCN, underscoring the necessity of polyamines in this process. Moreover, polyamine depletion regimens exert potent anti-tumor activity in pre-clinical models of established neuroblastoma as well, in combination with numerous chemotherapeutic agents and even in tumors with unfavorable genetic features such as MYCN, ALK or TP53 mutation. This has led to the testing of DFMO in clinical trials for children with neuroblastoma. Current trial designs include testing lower dose DFMO alone (2,000 mg/m2/day) starting at the completion of standard therapy, or higher doses combined with chemotherapy (up to 9,000 mg/m2/day) for patients with relapsed disease that has progressed. In this review we will discuss important considerations for the future design of DFMO-based clinical trials for neuroblastoma, focusing on the need to better define the principal mechanisms of anti-tumor activity for polyamine depletion regimens. Putative DFMO activities that are both cancer cell intrinsic (targeting the principal oncogenic driver, MYC) and cancer cell extrinsic (altering the tumor microenvironment to support anti-tumor immunity) will be discussed. Understanding the mechanisms of DFMO activity are critical in determining how it might be best leveraged in upcoming clinical trials. This mechanistic approach also provides a platform by which iterative pre-clinical testing using translational tumor models may complement our clinical approaches. PMID:26835380
A quantitative analysis of the polyamine in lung cancer patient fingernails by LC-ESI-MS/MS.
Min, Jun Zhe; Matsumoto, Akihito; Li, Gao; Jiang, Ying-Zi; Yu, Hai-Fu; Todoroki, Kenichiro; Inoue, Koichi; Toyo'oka, Toshimasa
2014-04-01
A quantitative analysis of polyamines in lung cancer patient fingernails by the combination of 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole derivatives and liquid chromatography-electrospray ionization tandem mass spectrometry is described. The reaction of the reagent with eight kinds of polyamines, that is, N(1) -acetylputrescine (N(1) -actPUT), N(8) -acetylspermidine, N(1) -acetylspermine, 1,3-diaminopropane, putrescine (PUT), cadaverine, spermidine and spermine (SPM) effectively occurs at 60 °C for 30 min. The detection limits (signal-to-noise ratio 5) were 5-100 fmol. A good linearity was achieved from the calibration curves, which was obtained by plotting the peak area ratios of the analytes relative to the internal standard (IS), that is, 1,6-diaminohexane, vs the injected amounts of polyamines (r(2) > 0.996), and the intra-day and inter-day assay precisions were <9.84%. Furthermore, the recoveries (%) of the polyamines spiked in the human fingernails were 89.14-110.64. The present method was applied to human fingernail samples from 17 lung cancer patients and 39 healthy volunteers. The polyamine concentration was different based on the gender, that is, the N(1) -actPUT and PUT contents were 3.10 times and 2.56 times higher in healthy men than in women, respectively. Additionally, in the lung cancer patient group, as compared with the healthy volunteers, the concentrations of SPM had a statistically significant (p < 0.05) correlation. Therefore, because the proposed method provides a good mass accuracy and the trace detection of the polyamines in human fingernails, this analytical technique could be a noninvasive technique to assist in the diagnosis and assessment of disease activity in lung cancer patients. Copyright © 2013 John Wiley & Sons, Ltd.
Li, Shucheng; Jin, Han; Zhang, Qiang
2016-01-01
Salt stress, particularly short-term salt stress, is among the most serious abiotic factors limiting plant survival and growth in China. It has been established that exogenous spermidine (Spd) stimulates plant tolerance to salt stress. The present study utilized two zoysiagrass cultivars commonly grown in China that exhibit either sensitive (cv. Z081) or tolerant (cv. Z057) adaptation capacity to salt stress. The two cultivars were subjected to 200 mM salt stress and treated with different exogenous Spd concentrations for 8 days. Polyamine [diamine putrescine (Put), tetraamine spermine (Spm), and Spd], H2O2 and malondialdehyde (MDA) contents and polyamine metabolic (ADC, ODC, SAMDC, PAO, and DAO) and antioxidant (superoxide dismutase, catalase, and peroxidase) enzyme activities were measured. The results showed that salt stress induced increases in Spd and Spm contents and ornithine decarboxylase (ODC), S-adenosylmethionine decarboxylase (SAMDC), and diamine oxidase (DAO) activities in both cultivars. Exogenous Spd application did not alter polyamine contents via regulation of polyamine-degrading enzymes, and an increase in polyamine biosynthetic enzyme levels was observed during the experiment. Increasing the concentration of exogenous Spd resulted in a tendency of the Spd and Spm contents and ODC, SAMDC, DAO, and antioxidant enzyme activities to first increase and then decrease in both cultivars. H2O2 and MDA levels significantly decreased in both cultivars treated with Spd. Additionally, in both cultivars, positive correlations between polyamine biosynthetic enzymes (ADC, SAMDC), DAO, and antioxidant enzymes (SOD, POD, CAT), but negative correlations with H2O2 and MDA levels, and the Spd + Spm content were observed with an increase in the concentration of exogenous Spd.
Li, Shucheng; Jin, Han; Zhang, Qiang
2016-01-01
Salt stress, particularly short-term salt stress, is among the most serious abiotic factors limiting plant survival and growth in China. It has been established that exogenous spermidine (Spd) stimulates plant tolerance to salt stress. The present study utilized two zoysiagrass cultivars commonly grown in China that exhibit either sensitive (cv. Z081) or tolerant (cv. Z057) adaptation capacity to salt stress. The two cultivars were subjected to 200 mM salt stress and treated with different exogenous Spd concentrations for 8 days. Polyamine [diamine putrescine (Put), tetraamine spermine (Spm), and Spd], H2O2 and malondialdehyde (MDA) contents and polyamine metabolic (ADC, ODC, SAMDC, PAO, and DAO) and antioxidant (superoxide dismutase, catalase, and peroxidase) enzyme activities were measured. The results showed that salt stress induced increases in Spd and Spm contents and ornithine decarboxylase (ODC), S-adenosylmethionine decarboxylase (SAMDC), and diamine oxidase (DAO) activities in both cultivars. Exogenous Spd application did not alter polyamine contents via regulation of polyamine-degrading enzymes, and an increase in polyamine biosynthetic enzyme levels was observed during the experiment. Increasing the concentration of exogenous Spd resulted in a tendency of the Spd and Spm contents and ODC, SAMDC, DAO, and antioxidant enzyme activities to first increase and then decrease in both cultivars. H2O2 and MDA levels significantly decreased in both cultivars treated with Spd. Additionally, in both cultivars, positive correlations between polyamine biosynthetic enzymes (ADC, SAMDC), DAO, and antioxidant enzymes (SOD, POD, CAT), but negative correlations with H2O2 and MDA levels, and the Spd + Spm content were observed with an increase in the concentration of exogenous Spd. PMID:27582752
Suppola, S; Heikkinen, S; Parkkinen, J J; Uusi-Oukari, M; Korhonen, V P; Keinänen, T; Alhonen, L; Jänne, J
2001-01-01
We have generated a hybrid transgenic mouse line overexpressing both ornithine decarboxylase (ODC) and spermidine/spermine N(1)-acetyltransferase (SSAT) under the control of the mouse metallothionein (MT) I promoter. In comparison with singly transgenic animals overexpressing SSAT, the doubly transgenic mice unexpectedly displayed much more striking signs of activated polyamine catabolism, as exemplified by a massive putrescine accumulation and an extreme reduction of hepatic spermidine and spermine pools. Interestingly, the profound depletion of the higher polyamines in the hybrid animals occurred in the presence of strikingly high ODC activity and tremendous putrescine accumulation. Polyamine catabolism in the doubly transgenic mice could be enhanced further by administration of zinc or the polyamine analogue N(1),N(11)-diethylnorspermine. In tracer experiments with [(14)C]spermidine we found that, in comparison with syngenic animals, both MT-ODC and MT-SSAT mice possessed an enhanced efflux mechanism for hepatic spermidine. In the MT-ODC animals this mechanism apparently operated in the absence of measurable SSAT activity. In the hybrid animals, spermidine efflux was stimulated further in comparison with the singly transgenic animals. In spite of a dramatic accumulation of putrescine and a profound reduction of the spermidine and spermine pools, only marginal changes were seen in the level of ODC antizyme. Even though the hybrid animals showed no liver or other organ-specific overt toxicity, except an early and permanent loss of hair, their life span was greatly reduced. These results can be understood from the perspective that catabolism is the overriding regulatory mechanism in the metabolism of the polyamines and that, even under conditions of severe depletion of spermidine and spermine, extremely high tissue pools of putrescine are not driven further to replenish the pools of the higher polyamines. PMID:11513732
Sunkara, P S; Chang, C C; Prakash, N J; Lachmann, P J
1985-09-01
The objective of the present study was to investigate the effect of polyamine depletion by alpha-difluoromethylornithine (DFMO), a specific irreversible inhibitor of ornithine decarboxylase, on the growth and differentiation of B16 melanoma cells grown in culture and also as solid tumors in mice. Polyamine depletion by DFMO (2.5 mM) resulted in a complete inhibition of cell growth in culture and a 90% inhibition of viability of melanoma cells as determined by clonogenic assay at the end of 7 days after DFMO treatment. These results indicate that polyamine depletion induced by DFMO is cytotoxic to B16 melanoma cells in culture. Furthermore a 2- to 5-fold increase in tyrosinase activity and 10-fold accumulation of melanine were observed in polyamine depleted cells compared to control cultures. These effects of DFMO could easily be reversed by the addition of putrescine simultaneously with DFMO. Administration of different doses of DFMO in drinking water to B16 melanoma tumor bearing mice also resulted in an increase in tyrosinase activity and a dose dependent inhibition (86-90%) of tumor growth. Although one cannot rule out the possibility of induction of differentiated phenotype as a result of antiproliferative activity of DFMO, the data presented indicate that the unique sensitivity of melanoma to DFMO may be due to a combination of cell growth inhibition and concomitant induction of differentiation upon polyamine depletion. The results of the present study indicate that polyamines play an important role in growth and differentiation of melanoma and also provide an example of inhibition of tumor cell growth by induction of cellular differentiation.
Baumgärtner, Benjamin; Möller, Hendrik; Neumann, Thomas
2017-01-01
A facile method to coat carbon fibers with a silica shell is presented in this work. By immobilizing linear polyamines on the carbon fiber surface, the high catalytic activity of polyamines in the sol–gel-processing of silica precursors is used to deposit a silica coating directly on the fiber’s surface. The surface localization of the catalyst is achieved either by attaching short-chain polyamines (e.g., tetraethylenepentamine) via covalent bonds to the carbon fiber surface or by depositing long-chain polyamines (e.g., linear poly(ethylenimine)) on the carbon fiber by weak non-covalent bonding. The long-chain polyamine self-assembles onto the carbon fiber substrate in the form of nanoscopic crystallites, which serve as a template for the subsequent silica deposition. The silicification at close to neutral pH is spatially restricted to the localized polyamine and consequently to the fiber surface. In case of the linear poly(ethylenimine), silica shells of several micrometers in thickness can be obtained and their morphology is easily controlled by a considerable number of synthesis parameters. A unique feature is the hierarchical biomimetic structure of the silica coating which surrounds the embedded carbon fiber by fibrillar and interconnected silica fine-structures. The high surface area of the nanostructured composite fiber may be exploited for catalytic applications and adsorption purposes. PMID:28685115
Michail, Karim; Aljuhani, Naif; Siraki, Arno G
2013-03-01
Synthetic and biological amines such as ethylenediamine (EDA), spermine, and spermidine have not been previously investigated in free-radical biochemical systems involving aniline-based drugs or xenobiotics. We aimed to study the influence of polyamines in the modulation of aromatic amine radical metabolites in peroxidase-mediated free radical reactions. The aniline compounds tested caused a relatively low oxidation rate of glutathione in the presence of horseradish peroxidase (HRP), and H2O2; however, they demonstrated marked oxygen consumption when a polyamine molecule was present. Next, we characterized the free-radical products generated by these reactions using spin-trapping and electron paramagnetic resonance (EPR) spectrometry. Primary and secondary but not tertiary polyamines dose-dependently enhanced the N-centered radicals of different aniline compounds catalyzed by either HRP or myeloperoxidase, which we believe occurred via charge transfer intermediates and subsequent stabilization of aniline-derived radical species as suggested by isotopically labeled aniline. Aniline/peroxidase reaction product(s) were monitored at 435 nm by kinetic spectrophotometry in the presence and absence of a polyamine additive. Using gas chromatography-mass spectrometry, the dimerziation product of aniline, azobenzene, was significantly amplified when EDA was present. In conclusion, di- and poly-amines are capable of enhancing the formation of aromatic-amine-derived free radicals, a fact that is expected to have toxicological consequences.
Baumgärtner, Benjamin; Möller, Hendrik; Neumann, Thomas; Volkmer, Dirk
2017-01-01
A facile method to coat carbon fibers with a silica shell is presented in this work. By immobilizing linear polyamines on the carbon fiber surface, the high catalytic activity of polyamines in the sol-gel-processing of silica precursors is used to deposit a silica coating directly on the fiber's surface. The surface localization of the catalyst is achieved either by attaching short-chain polyamines (e.g., tetraethylenepentamine) via covalent bonds to the carbon fiber surface or by depositing long-chain polyamines (e.g., linear poly(ethylenimine)) on the carbon fiber by weak non-covalent bonding. The long-chain polyamine self-assembles onto the carbon fiber substrate in the form of nanoscopic crystallites, which serve as a template for the subsequent silica deposition. The silicification at close to neutral pH is spatially restricted to the localized polyamine and consequently to the fiber surface. In case of the linear poly(ethylenimine), silica shells of several micrometers in thickness can be obtained and their morphology is easily controlled by a considerable number of synthesis parameters. A unique feature is the hierarchical biomimetic structure of the silica coating which surrounds the embedded carbon fiber by fibrillar and interconnected silica fine-structures. The high surface area of the nanostructured composite fiber may be exploited for catalytic applications and adsorption purposes.
Park, Ju Yeon; Kang, Beom Ryong; Ryu, Choong-Min; Anderson, Anne J; Kim, Young Cheol
2018-05-01
The Gac/Rsm network regulates, at the transcriptional level, many beneficial traits in biocontrol-active pseudomonads. In this study, we used Phenotype MicroArrays, followed by specific growth studies and mutational analysis, to understand how catabolism is regulated by this sensor kinase system in the biocontrol isolate Pseudomonas chlororaphis O6. The growth of a gacS mutant was decreased significantly relative to that of the wild-type on ornithine and arginine, and on the precursor of these amino acids, N-acetyl-l-glutamic acid. The gacS mutant also showed reduced production of polyamines. Expression of the genes encoding arginine decarboxylase (speA) and ornithine decarboxylases (speC) was controlled at the transcriptional level by the GacS sensor of P. chlororaphis O6. Polyamine production was reduced in the speC mutant, and was eliminated in the speAspeC mutant. The addition of exogenous polyamines to the speAspeC mutant restored the in vitro growth inhibition of two fungal pathogens, as well as the secretion of three biological control-related factors: pyrrolnitrin, protease and siderophore. These results extend our knowledge of the regulation by the Gac/Rsm network in a biocontrol pseudomonad to include polyamine synthesis. Collectively, our studies demonstrate that bacterial polyamines act as important regulators of bacterial cell growth and biocontrol potential. © 2017 BSPP AND JOHN WILEY & SONS LTD.
Nikolic, Goran; Zlatkovic, Sasa; Cakic, Milorad; Cakic, Suzana; Lacnjevac, Caslav; Rajic, Zoran
2010-01-01
The use of fast FT-IR spectroscopy as a sensitive method to estimate a change of the crosslinking kinetics of epoxy resin with polyamine adducts is described in this study. A new epoxy formulation based on the use of polyamine adducts as the hardeners was analyzed. Crosslinking reactions of the different stoichiometric mixtures of the unmodified GY250 epoxy resin with the aliphatic EH606 and the cycloaliphatic EH637 polyamine adducts were studied using mid FT-IR spectroscopic techniques. As the crosslinking proceeded, the primary amine groups in polyamine adduct are converted to secondary and the tertiary amines. The decrease in the IR band intensity of epoxy groups at about 915 cm−1, as well as at about 3,056 cm−1, was observed due to process. Mid IR spectral analysis was used to calculate the content of the epoxy groups as a function of crosslinking time and the crosslinking degree of resin. The amount of all the epoxy species was estimated from IR spectra to changes during the crosslinking kinetics of epichlorhydrin. PMID:22315562
Academic Conversations: Classroom Talk That Fosters Critical Thinking and Content Understandings
ERIC Educational Resources Information Center
Zwiers, Jeff; Crawford, Marie
2011-01-01
Where would we be without conversation? Throughout history, conversations have allowed us to see different perspectives, build ideas, and solve problems. Conversations, particularly those referred to in this book as academic conversations, push students to think and learn in lasting ways. Academic conversations are back-and-forth dialogues in…
Antineoplastic Efficacy of Novel Polyamine Analogues in Human Breast Cancer
2005-06-01
Davidson, N.E., and Casero, R.A.. Spermine oxidase SMO(PAOh1), not N1-acetylpolyamine oxidase (PAO) is the primary source of cytotoxic H2O2 in polyamine... spermine oxidase (PAOh1/SMO) mRNA and activity by a polyamine analogue in human breast cancer cell lines. The fourth Era of Hope meeting for the...SMO/PAOh1 Spermine Oxidase DFMO α-difluoromethylornithine BENSpm N1, N11-bis(ethyl)norspermine CHEMSpm N1-(cycloheptylmethyl)-N11-ethyl- 4,8
Simoni, Elena; Bergamini, Christian; Fato, Romana; Tarozzi, Andrea; Bains, Sandip; Motterlini, Roberto; Cavalli, Andrea; Bolognesi, Maria Laura; Minarini, Anna; Hrelia, Patrizia; Lenaz, Giorgio; Rosini, Michela; Melchiorre, Carlo
2010-10-14
Mitochondria-directed antioxidants 2-5 were designed by conjugating curcumin congeners with different polyamine motifs as vehicle tools. The conjugates emerged as efficient antioxidants in mitochondria and fibroblasts and also exerted a protecting role through heme oxygenase-1 activation. Notably, the insertion of a polyamine function into the curcumin-like moiety allowed an efficient intracellular uptake and mitochondria targeting. It also resulted in a significant decrease in the cytotoxicity effects. 2-5 are therefore promising molecules for neuroprotectant lead discovery.
Unal, Meral; Palavan-Unsal, Narcin; Tufekci, M A
2008-03-01
The genotoxic and cytotoxic effects of exogenous polyamines (PAs), putrescine (Put), spermidine (Spd), spermine (Spm) and PA biosynthetic inhibitors, alpha-difluoromethylornithine (DFMO), cyclohexilamine (CHA), methylglioxal bis-(guanylhydrazone) (MGBG) were investigated in the root meristems of Allium cepa L. The reduction of mitotic index and the induction of chromosomal aberrations such as bridges, stickiness, c-mitotic anaphases, micronuclei, endoredupliction by PAs and PA biosynthetic inhibitors were observed and these were used as evidence of genotoxicity and cytotoxicity.
Meana, Clara; Rubín, José Manuel; Bordallo, Carmen; Suárez, Lorena; Bordallo, Javier; Sánchez, Manuel
2016-02-01
Polyamines contribute to several physiological and pathological processes, including cardiac hypertrophy in experimental animals. This involves an increase in ornithine decarboxylase (ODC) activity and intracellular polyamines associated with cyclic adenosine monophosphate (cAMP) increases. The aim of the study was to establish the role of these in the human heart in living patients. For this, polyamines (by high performance liquid chromatography) and the activity of ODC and N(1)-acetylpolyamine oxidases (APAO) were determined in the right atrial appendage of 17 patients undergoing extracorporeal circulation to correlate with clinical parameters. There existed enzymatic activity associated with the homeostasis of polyamines. Left atria size was positively associated with ODC (r = 0.661, P = 0.027) and negatively with APAO-N(1) -acetylspermine (r = -0.769, P = 0.026), suggesting that increased levels of polyamines are associated with left atrial hemodynamic overload. Left ventricular ejection fraction (LVEF) and heart rate were positively associated with spermidine (r = 0.690, P = 0.003; r = 0.590, P = 0.021) and negatively with N(1)-acetylspermidine (r = -0.554, P = 0.032; r = -0.644, P = 0.018). LVEF was negatively correlated with cAMP levels (r = -0.835, P = 0.001) and with cAMP/ODC (r = -0.794, P = 0.011), cAMP/spermidine (r = -0.813, P = 0.001) and cAMP/spermine (r = -0.747, P = 0.003) ratios. Abnormal LVEF patients showed decreased ODC activity and spermidine, and increased N(1) -acetylspermidine, and cAMP. Spermine decreased in congestive heart failure patients. The trace amine isoamylamine negatively correlated with septal wall thickness (r = -0.634, P = 0.008) and was increased in cardiac heart failure. The results indicated that modifications in polyamine homeostasis might be associated with cardiac function and remodelling. Increased cAMP might have a deleterious effect on function. Further studies should confirm these findings and the involvement of polyamines in different stages of heart failure. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.
Targeting a Novel Plasmodium falciparum Purine Recycling Pathway with Specific Immucillins
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ting, L; Shi, W; Lewandowicz, A
Plasmodium falciparum is unable to synthesize purine bases and relies upon purine salvage and purine recycling to meet its purine needs. We report that purines formed as products of the polyamine pathway are recycled in a novel pathway in which 5'-methylthioinosine is generated by adenosine deaminase. The action of P. falciparum purine nucleoside phosphorylase is a convergent step of purine salvage, converting both 5'-methylthioinosine and inosine to hypoxanthine. We used accelerator mass spectrometry to verify that 5'-methylthioinosine is an active nucleic acid precursor in P. falciparum. Prior studies have shown that inhibitors of purine salvage enzymes kill malaria, but potentmore » malaria-specific inhibitors of these enzymes have not previously been described. 5'-methylthio-Immucillin-H, a transition state analogue inhibitor that is selective for malarial over human purine nucleoside phosphorylase, kills P. falciparum in culture. Immucillins are currently in clinical trials for other indications and may have application as antimalarials.« less
BET, thermal degradation, and FTIR spectras of triazine polyamine polymers.
Can, Mustafa
2017-04-01
Here we show effect of the polyamine polymer chain length to BET isotherms. According to IUPAC classification [1], all three polymers are fitting type 1 physical adsorption isotherm with H3 hysteresis (except for EDA having H2 hysteresis). Moreover, TG and TGA analysis of polymers triazine-ethylenediamine (EDA) and triazine-triethylenetetramine (TETA) are provided. Due to the similarities of the structure, main decomposition temperatures are close to each other (between 593 K and 873 K). In order to understand change of FTIR spectra with adsorption and stripping Au(III), fresh, Au(III) adsorbed and recycled spectras of polymers measured. For further discussions about the effect of chain length to adsorption of Au(III) onto triazine polyamine polymer particles "Au (III) Uptake by Triazine Polyamine Polymers: Mechanism, Kinetic and Equilibrium Studies" Can et al. [2] (article in press).
Improved method for HPLC analysis of polyamines, agmatine and aromatic monoamines in plant tissue
NASA Technical Reports Server (NTRS)
Slocum, R. D.; Flores, H. E.; Galston, A. W.; Weinstein, L. H.
1989-01-01
The high performance liquid chromatographic (HPLC) method of Flores and Galston (1982 Plant Physiol 69: 701) for the separation and quantitation of benzoylated polyamines in plant tissues has been widely adopted by other workers. However, due to previously unrecognized problems associated with the derivatization of agmatine, this important intermediate in plant polyamine metabolism cannot be quantitated using this method. Also, two polyamines, putrescine and diaminopropane, also are not well resolved using this method. A simple modification of the original HPLC procedure greatly improves the separation and quantitation of these amines, and further allows the simulation analysis of phenethylamine and tyramine, which are major monoamine constituents of tobacco and other plant tissues. We have used this modified HPLC method to characterize amine titers in suspension cultured carrot (Daucas carota L.) cells and tobacco (Nicotiana tabacum L.) leaf tissues.
Gómez-Gallego, C; Recio, I; Gómez-Gómez, V; Ortuño, I; Bernal, M J; Ros, G; Periago, M J
2016-02-01
This study examined the influence of processing on polyamines and peptide release after the digestion of a commercial infant formula designed for children during the first months of life. Polyamine oxidase activity was not suppressed during the manufacturing process, which implicates that polyamine concentrations were reduced over time and during infant formula self-life. In gel electrophoresis, in vitro gastrointestinal digestion of samples with reduced amount of enzymes and time of digestion shows an increase in protein digestibility, reflected in the increase in nonprotein nitrogen after digestion and the disappearance of β-lactoglobulin and α-lactalbumin bands in gel electrophoresis. Depending on the sample, between 22 and 87 peptides were identified after gastrointestinal digestion. A peptide from β-casein f(98-105) with the sequence VKEAMAPK and antioxidant activity appeared in all of the samples. Other peptides with antioxidant, immunomodulatory, and antimicrobial activities were frequently found, which could have an effect on infant health. The present study confirms that the infant formula manufacturing process determines the polyamine content and peptidic profile after digestion of the infant formula. Because compositional dissimilarity between human milk and infant formula in polyamines and proteins could be responsible for some of the differences in health reported between breast-fed and formula-fed children, these changes must be taken into consideration because they may have a great effect on infant nutrition and development. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Arndt, Mary Ann; Battaglia, Valentina; Parisi, Eva; Lortie, Mark J.; Isome, Masato; Baskerville, Christopher; Pizzo, Donald P.; Ientile, Riccardo; Colombatto, Sebastiano; Toninello, Antonio; Satriano, Joseph
2009-01-01
Agmatine, an endogenous metabolite of arginine, selectively suppresses growth in cells with high proliferative kinetics, such as transformed cells, through depletion of intracellular polyamine levels. In the present study, we depleted intracellular polyamine content with agmatine to determine if attrition by cell death contributes to the growth-suppressive effects. We did not observe an increase in necrosis, DNA fragmentation, or chromatin condensation in Ha-Ras-transformed NIH-3T3 cells administered agmatine. In response to Ca2+-induced oxidative stress in kidney mitochondrial preparations, agmatine demonstrated attributes of a free radical scavenger by protecting against the oxidation of sulfhydryl groups and decreasing hydrogen peroxide content. The functional outcome was a protective effect against Ca2+-induced mitochondrial swelling and mitochondrial membrane potential collapse. We also observed decreased expression of proapoptotic Bcl-2 family members and of execution caspase-3, implying antiapoptotic potential. Indeed, we found that apoptosis induced by camptothecin or 5-fluorourocil was attenuated in cells administered agmatine. Agmatine may offer an alternative to the ornithine decarboxylase inhibitor difluoromethyl ornithine for depletion of intracellular polyamine content while avoiding the complications of increasing polyamine import and reducing the intracellular free radical scavenger capacity of polyamines. Depletion of intracellular polyamine content with agmatine suppressed cell growth, yet its antioxidant capacity afforded protection from mitochondrial insult and resistance to cellular apoptosis. These results could explain the beneficial outcomes observed with agmatine in models of injury and disease. PMID:19321739
Polyamine regulation of ornithine decarboxylase and its antizyme in intestinal epithelial cells.
Yuan, Q; Ray, R M; Viar, M J; Johnson, L R
2001-01-01
Ornithine decarboxylase (ODC) is feedback regulated by polyamines. ODC antizyme mediates this process by forming a complex with ODC and enhancing its degradation. It has been reported that polyamines induce ODC antizyme and inhibit ODC activity. Since exogenous polyamines can be converted to each other after they are taken up into cells, we used an inhibitor of S-adenosylmethionine decarboxylase, diethylglyoxal bis(guanylhydrazone) (DEGBG), to block the synthesis of spermidine and spermine from putrescine and investigated the specific roles of individual polyamines in the regulation of ODC in intestinal epithelial crypt (IEC-6) cells. We found that putrescine, spermidine, and spermine inhibited ODC activity stimulated by serum to 85, 46, and 0% of control, respectively, in the presence of DEGBG. ODC activity increased in DEGBG-treated cells, despite high intracellular putrescine levels. Although exogenous spermidine and spermine reduced ODC activity of DEGBG-treated cells close to control levels, spermine was more effective than spermidine. Exogenous putrescine was much less effective in inducing antizyme than spermidine or spermine. High putrescine levels in DEGBG-treated cells did not induce ODC antizyme when intracellular spermidine and spermine levels were low. The decay of ODC activity and reduction of ODC protein levels were not accompanied by induction of antizyme in the presence of DEGBG. Our results indicate that spermine is the most, and putrescine the least, effective polyamine in regulating ODC activity, and upregulation of antizyme is not required for the degradation of ODC protein.
design TEA LCA Biochemical conversion process pathways Algal biomass production and conversion pathways Production," Green Chemistry (2015) Process Design and Economics for the Conversion of Lignocellulosic Production," Applied Energy (2011) Process Design and Economics for Biochemical Conversion of
Synthesis and Application of Pyrrolidone-containing Shale Inhibitors
NASA Astrophysics Data System (ADS)
Liu, Yonggui; Hou, Jie; Zhang, Yang; Yan, Jing; Song, Tao; Xu, Yongjun
2018-03-01
New generation polyamine inhibitors are amino-terminated polyethers with excellent inhibiting capabilities; they play a key role in borehole stabilization and reservoir protection. However, polyamine inhibitors are limited by their poor thermal stability, which can be attributed to the presence of ether bonds in their molecular structures. We propose a three-step synthesis approach fora novel pyrrolidone-containing polyamine inhibitor (DYNP) by introducing N-vinyl-2-pyrrolidone (NVP) on divinyloxyethane. This polyamine inhibitor exhibits an optimized molecular structure and has enhanced heat resistance. Characterizations by infrared (IR) spectroscopy and evaluation tests demonstrate several advantages of DYNP inhibitors, including excellent inhibiting capability (superior to similar materials such as polyamines), improved heat resistance (reasonable stability at temperatures up to 240°C), and good compatibility with both fresh water and salt water drilling fluids. These can be attributed to the presence of considerable amounts of amino groups in the repeating unit of DYNP molecules. The DYNP inhibitor was applied in over 20 boreholes in tight oil blocks in Daqing Oilfield to relieve hydration of formations with high shale contents. For instance, drilling in the 2033.5m horizontal section of Dragon 2 borehole was smooth, with a borehole diameter expansion ratio below 10%.
Nuclear aggregates of polyamines in a radiation-induced DNA damage model.
Iacomino, Giuseppe; Picariello, Gianluca; Stillitano, Ilaria; D'Agostino, Luciano
2014-02-01
Polyamines (PA) are believed to protect DNA minimizing the effect of radiation damage either by inducing DNA compaction and aggregation or acting as scavengers of free radicals. Using an in vitro pDNA double strand breakage assay based on gel electrophoretic mobility, we compared the protective capability of PA against γ-radiation with that of compounds generated by the supramolecular self-assembly of nuclear polyamines and phosphates, named Nuclear Aggregates of Polyamines (NAPs). Both unassembled PA and in vitro produced NAPs (ivNAPs) were ineffective in conferring pDNA protection at the sub-mM concentration. Single PA showed an appreciable protective effect only at high (mM) concentrations. However, concentrations of spermine (4+) within a critical range (0.481 mM) induced pDNA precipitation, an event that was not observed with NAPs-pDNA interaction. We conclude that the interaction of individual PA is ineffective to assure DNA protection, simultaneously preserving the flexibility and charge density of the double strand. Furthermore, data obtained by testing polyamine and ivNAPS with the current radiation-induced DNA damage model support the concept that PA-phosphate aggregates are the only forms through which PA interact with DNA. Copyright © 2013 Elsevier Ltd. All rights reserved.
Maddox, A M; Freireich, E J; Keating, M J; Haddox, M K
1988-03-01
Nine patients with hematological malignancies were treated with difluoromethylornithine and methylglyoxal bis(guanylhydrazone). The number of circulating blast cells decreased in all of the patients treated with DFMO and MGBG for longer than 1 wk. Morphological evidence of myeloid maturation was evident in four patients with leukemia and the circulating M Protein decreased in one patient with multiple myeloma. The polyamine content of the mononuclear cells in both the peripheral blood and bone marrow was transiently increased after the initial MGBG dose. During administration of DFMO decreases were achieved in the peripheral blood mononuclear cell putrescine levels in 7 patients, spermidine levels in 5 patients, and spermine levels in 4 patients. Alterations in bone marrow mononuclear cell polyamine levels were similar to those which occurred in the peripheral cells. An average of 9 days of DFMO treatment was required to lower mononuclear cell polyamine levels. Three of the 4 evaluable patients receiving multiple MGBG doses had an increased mononuclear cell content of MGBG after DFMO pretreatment. Enhancement of cellular MGBG levels was not directly correlated to the degree of cellular polyamine depletion.
Polyamine interactions with plant hormones: crosstalk at several levels
USDA-ARS?s Scientific Manuscript database
Polyamines play important roles in diverse plant growth and development processes including seed germination, tissue lignification, organogenesis, flowering, pollination, embryogenesis, fruit development, ripening, abscission, senescence and stress responses. In all these processes, synergistic and ...
Polyamine sensitization in offshore workers handling drilling muds.
Ormerod, A D; Wakeel, R A; Mann, T A; Main, R A; Aldridge, R D
1989-11-01
Oil-based mud, a complex mixture containing amines in emulsifiers, is used in offshore drilling operations. It is a skin irritant that occasionally gives rise to allergic contact sensitivity. In patch testing patients with allergy to drilling mud, we have identified polyamine (diethylenetriamine and triethylenetetramine) sensitivity in 5 patients. All 5 patients were also allergic to emulsifiers. These emulsifiers are cross-linked fatty acid amido-amines, in which unreacted amine groups are thought to cross-sensitize with these constituent polyamines. Cross-reactivity between ethylenediamine, diethylenetetramine and triethylenetetramine was found in 9 subjects.
Gong, Xiaoqing; Liu, Ji-Hong
2017-01-01
High-performance liquid chromatography (HPLC) is a sensitive, rapid, and accurate technique to detect and characterize various metabolites from plants. The metabolites are extracted with different solvents and eluted with appropriate mobile phases in a designed HPLC program. Polyamines are known to accumulate under abiotic stress conditions in various plant species and thought to provide protection against oxidative stress by scavenging reactive oxygen species. Here, we describe a common method to detect the free polyamines in plant tissues both qualitatively and quantitatively.
Okada, Kazuma; Hidese, Ryota; Fukuda, Wakao; Niitsu, Masaru; Takao, Koichi; Horai, Yuhei; Umezawa, Naoki; Higuchi, Tsunehiko; Oshima, Tairo; Yoshikawa, Yuko; Imanaka, Tadayuki
2014-01-01
Longer- and/or branched-chain polyamines are unique polycations found in thermophiles. N4-aminopropylspermine is considered a major polyamine in Thermococcus kodakarensis. To determine whether a quaternary branched penta-amine, N4-bis(aminopropyl)spermidine, an isomer of N4-aminopropylspermine, was also present, acid-extracted cytoplasmic polyamines were analyzed by high-pressure liquid chromatography, gas chromatography (HPLC), and gas chromatography-mass spectrometry. N4-bis(aminopropyl)spermidine was an abundant cytoplasmic polyamine in this species. To identify the enzyme that catalyzes N4-bis(aminopropyl)spermidine synthesis, the active fraction was concentrated from the cytoplasm and analyzed by linear ion trap–time of flight mass spectrometry with an electrospray ionization instrument after analysis by the MASCOT database. TK0545, TK0548, TK0967, and TK1691 were identified as candidate enzymes, and the corresponding genes were individually cloned and expressed in Escherichia coli. Recombinant forms were purified, and their N4-bis(aminopropyl)spermidine synthesis activity was measured. Of the four candidates, TK1691 (BpsA) was found to synthesize N4-bis(aminopropyl)spermidine from spermidine via N4-aminopropylspermidine. Compared to the wild type, the bpsA-disrupted strain DBP1 grew at 85°C with a slightly longer lag phase but was unable to grow at 93°C. HPLC analysis showed that both N4-aminopropylspermidine and N4-bis(aminopropyl)spermidine were absent from the DBP1 strain grown at 85°C, demonstrating that the branched-chain polyamine synthesized by BpsA is important for cell growth at 93°C. Sequence comparison to orthologs from various microorganisms indicated that BpsA differed from other known aminopropyltransferases that produce spermidine and spermine. BpsA orthologs were found only in thermophiles, both in archaea and bacteria, but were absent from mesophiles. These findings indicate that BpsA is a novel aminopropyltransferase essential for the synthesis of branched-chain polyamines, enabling thermophiles to grow in high-temperature environments. PMID:24610711
Focused Review: Agmatine in Fermented Foods
Galgano, Fernanda; Caruso, Marisa; Condelli, Nicola; Favati, Fabio
2012-01-01
Polyamines (PAs) are ubiquitous substances considered to be bioregulators of numerous cell functions; they take part in cell growth, division, and differentiation. These biogenic amines are also involved in tissue repair and in intracellular signaling; in fact, because of their polycationic character, they interact to a large extent with membrane phospholipids and may play an important role in the regulation of membrane-linked enzymes. The intracellular polyamine content derives from the simultaneous regulation of the synthesis, catabolism, uptake, and elimination of the polyamines; furthermore, PAs are present in all cell types at different concentrations, but the highest levels are found in rapid-turnover tissues. In addition to spermidine, spermine, and putrescine, also agmatine (AGM), deriving from arginine and identified in mammals in the 1990s, is a polyamine and several studies have reported its potentially positive role in the production of secretagogues, and in neuronal, vascular, metabolic, and therapeutic functions. Because of the low arginine decarboxylase (ADC) activity in mammalians, the amounts of AGM found in their tissues can be only minimally ascribed to an endogenous de novo synthesis by ADC, while a substantial quantity of AGM may be of dietary origin. Several food products contain only small amounts of polyamines, while higher concentrations can be found in fermented foods. PAs could also be considered as indicators of freshness in fish and meat products; as these moieties are produced during food storage, it would seem to confirm the main role of microorganisms in their synthesis. In particular, high levels of AGM are present in alcoholic beverages, such as wine, beer, sake, which would seem to confirm the role of yeasts in AGM production. Although many biological functions have been attributed to polyamines, high levels of these compounds in foodstuffs can have toxicological effects; however, no safe level for the intake of polyamines in a diet has yet been established. In this paper the presence of AGM in different foodstuffs is discussed, also taking into account the various factors affecting its presence and concentration. PMID:22701114
Effect of MeJA treatment on polyamine, energy status and anthracnose rot of loquat fruit.
Cao, Shifeng; Cai, Yuting; Yang, Zhenfeng; Joyce, Daryl C; Zheng, Yonghua
2014-02-15
The effect of methyl jasmonate (MeJA) on changes in polyamines content and energy status and their relation to disease resistance was investigated. Freshly harvested loquat fruit were treated with 10 μmol l(-1) MeJA and wound inoculated with Colletotrichum acutatum spore suspension (1.0 × 10(5) spores ml(-1)) after 24h, and then stored at 20 °C for 6 days. MeJA treatment significantly reduced decay incidence. MeJA treated fruit manifested higher contents of polyamines (putrescine, spermidine and spermine) compared with the control fruit, during storage. MeJA treatment also maintained higher levels of adenosine triphosphate, and suppressed an increase in adenosine monophosphate content in loquat fruit. These results suggest that MeJA treatment may inhibit anthracnose rot by increasing polyamine content and maintaining the energy status. Copyright © 2013. Published by Elsevier Ltd.
Kurauchi, Isao; Shigemi, Kazutaka; Kabuki, Yusuke; Hamasu, Kousuke; Yamane, Haruka; Aoki, Mami; Kawada, Yoko; Morishita, Koji; Denbow, D Michael; Furuse, Mitsuhiro
2010-02-01
To clarify whether L-ornithine and/or its metabolite involves sedative and hypnotic effects under social separation stress, the effects of intracerebroventricular (i.c.v.) injection of L-ornithine and polyamines (putrescine, spermidine and spermine) were compared in chicks. Birds were injected i.c.v. with 0.5 mumol of L-ornithine, putrescine, spermidine, spermine or saline (control). After injection, chicks were immediately separated from the flock and monitored for the number of distress vocalizations and various postures. L-Ornithine greatly attenuated the stress response and caused sedative and hypnotic effects. Among the polyamines, only putrescine attenuated distress vocalizations but did not induce sleep. In conclusion, the sedative and hypnotic effect of L-ornithine was mainly induced by L-ornithine itself, while the polyamines contributed to the sedative, but not hypnotic, effect under social separation stress.
Verlinden, Bianca K; Niemand, Jandeli; Snyman, Janette; Sharma, Shiv K; Beattie, Ross J; Woster, Patrick M; Birkholtz, Lyn-Marie
2011-10-13
A series of alkylated (bis)urea and (bis)thiourea polyamine analogues were synthesized and screened for antimalarial activity against chloroquine-sensitive and -resistant strains of Plasmodium falciparum in vitro. All analogues showed growth inhibitory activity against P. falciparum at less than 3 μM, with the majority having effective IC(50) values in the 100-650 nM range. Analogues arrested parasitic growth within 24 h of exposure due to a block in nuclear division and therefore asexual development. Moreover, this effect appears to be cytotoxic and highly selective to malaria parasites (>7000-fold lower IC(50) against P. falciparum) and is not reversible by the exogenous addition of polyamines. With this first report of potent antimalarial activity of polyamine analogues containing 3-7-3 or 3-6-3 carbon backbones and substituted terminal urea- or thiourea moieties, we propose that these compounds represent a structurally novel class of antimalarial agents.
Influence of breast milk polyamines on suckling rat immune system maturation.
Pérez-Cano, Francisco J; González-Castro, Ana; Castellote, Cristina; Franch, Angels; Castell, Margarida
2010-02-01
The aim of this study was to ascertain whether the supplementation of polyamines present in breast milk, i.e. spermine (SPM) and spermidine (SPD), influenced the post-natal maturation of the systemic and intestinal immune system in rats. From birth, pups daily received SPM or SPD. At 5, 11 and 18 days old, small intestine intraepithelial lymphocytes (IEL), lamina propria lymphocytes (LPL) and splenocytes were phenotypically characterized. SPM and, less evidently, SPD accelerated the maturation of CD8+ IEL, and enhanced the presence of intraepithelial NK cells and IEL related with specific immune responses on the proximal and distal small intestine, respectively. Polyamines increased the percentage of more mature CD4+ LPL and enhanced the early presence of splenic B cells and, later, that of NK cells. However, no effect on Ig-secretory function was detected. These results suggest that breast milk polyamines improve the maturation of the rat intestinal and systemic immune system.
5 CFR 362.107 - Conversion to the competitive service.
Code of Federal Regulations, 2013 CFR
2013-01-01
... REGULATIONS PATHWAYS PROGRAMS General Provisions § 362.107 Conversion to the competitive service. (a) Subject... Pathways Program, an agency may noncompetitively convert an eligible Pathways Participant to a term or permanent competitive service position. (b) A Pathways Participant who is noncompetitively converted to a...
5 CFR 362.107 - Conversion to the competitive service.
Code of Federal Regulations, 2014 CFR
2014-01-01
... REGULATIONS PATHWAYS PROGRAMS General Provisions § 362.107 Conversion to the competitive service. (a) Subject... Pathways Program, an agency may noncompetitively convert an eligible Pathways Participant to a term or permanent competitive service position. (b) A Pathways Participant who is noncompetitively converted to a...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hai, Yang; Christianson, David W.
Leishmaniaarginase is a potential drug target for the treatment of leishmaniasis because this binuclear manganese metalloenzyme initiatesde novopolyamine biosynthesis by catalyzing the hydrolysis of L-arginine to generate L-ornithine and urea. The product L-ornithine subsequently undergoes decarboxylation to yield putrescine, which in turn is utilized for spermidine biosynthesis. Polyamines such as spermidine are essential for the growth and survival of the parasite, so inhibition of enzymes in the polyamine-biosynthetic pathway comprises an effective strategy for treating parasitic infections. To this end, two X-ray crystal structures ofL. mexicanaarginase complexed with α,α-disubstituted boronic amino-acid inhibitors based on the molecular scaffold of 2-(S)-amino-6-boronohexanoic acidmore » are now reported. Structural comparisons with human and parasitic arginase complexes reveal interesting differences in the binding modes of the additional α-substituents,i.e.the D side chains, of these inhibitors. Subtle differences in the three-dimensional contours of the outer active-site rims among arginases from different species lead to different conformations of the D side chains and thus different inhibitor-affinity trends. The structures suggest that it is possible to maintain affinity while fine-tuning intermolecular interactions of the D side chain of α,α-disubstituted boronic amino-acid inhibitors in the search for isozyme-specific and species-specific arginase inhibitors.« less
Diao, Qian-Nan; Song, Yong-Jun; Shi, Dong-Mei; Qi, Hong-Yan
Polyamines (PAs) and nitric oxide (NO) are vital signals in modulating plant response to abiotic stress. However, to our knowledge, studies on the relationship between NO and PAs in response to cold stress in tomato are limited. Accordingly, in this study, we investigated the effects of putrescine (Put) and spermidine (Spd) on NO generation and the function of Spd-induced NO in the tolerance of tomato seedling under chilling stress. Spd increased NO release via the nitric oxide synthase (NOS)-like and nitrate reductase (NR) enzymatic pathways in the seedlings, whereas Put had no such effect. Moreover, H 2 O 2 might act as an upstream signal to stimulate NO production. Both exogenous NO donor (sodium nitroprusside (SNP)) and Spd enhanced chilling tolerance in tomato, thereby protecting the photosynthetic system from damage. Compared to chilling treatment alone, Spd enhanced the gene expressions of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), and their enzyme activities in tomato leaves. However, a scavenger or inhibitor of NO abolished Spd-induced chilling tolerance and blocked the increased expression and activity due to Spd of these antioxidant enzymes in tomato leaves under chilling stress. The results showed that NO induced by Spd plays a crucial role in tomato's response to chilling stress.
Diao, Qian-Nan; Song, Yong-Jun; Shi, Dong-Mei; Qi, Hong-Yan
2016-01-01
Polyamines (PAs) and nitric oxide (NO) are vital signals in modulating plant response to abiotic stress. However, to our knowledge, studies on the relationship between NO and PAs in response to cold stress in tomato are limited. Accordingly, in this study, we investigated the effects of putrescine (Put) and spermidine (Spd) on NO generation and the function of Spd-induced NO in the tolerance of tomato seedling under chilling stress. Spd increased NO release via the nitric oxide synthase (NOS)-like and nitrate reductase (NR) enzymatic pathways in the seedlings, whereas Put had no such effect. Moreover, H2O2 might act as an upstream signal to stimulate NO production. Both exogenous NO donor (sodium nitroprusside (SNP)) and Spd enhanced chilling tolerance in tomato, thereby protecting the photosynthetic system from damage. Compared to chilling treatment alone, Spd enhanced the gene expressions of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), and their enzyme activities in tomato leaves. However, a scavenger or inhibitor of NO abolished Spd-induced chilling tolerance and blocked the increased expression and activity due to Spd of these antioxidant enzymes in tomato leaves under chilling stress. The results showed that NO induced by Spd plays a crucial role in tomato’s response to chilling stress. PMID:27921397
Polyamines are traps for reactive intermediates in furan metabolism
Peterson, Lisa A.; Phillips, Martin B.; Lu, Ding; Sullivan, Mathilde M.
2011-01-01
Furan is toxic and carcinogenic in rodents. Because of the large potential for human exposure, furan is classified as a possible human carcinogen. The detailed mechanism by which furan causes toxicity and cancer is not yet known. Since furan toxicity requires cytochrome P450-catalyzed oxidation of furan, we have characterized the urinary and hepatocyte metabolites of furan to gain insight into the chemical nature of the reactive intermediate. Previous studies in hepatocytes indicated that furan is oxidized to the reactive α,β-unsaturated dialdehyde, cis-2-butene-1,4-dial (BDA), which reacts with glutathione (GSH) to form 2-(S-glutathionyl)-succinaldehyde (GSH-BDA). This intermediate forms pyrrole cross-links with cellular amines such as lysine and glutamine. In this report, we demonstrate that GSH-BDA also forms cross-links with ornithine, putrescine and spermidine when furan is incubated with rat hepatocytes. The relative levels of these metabolites are not completely explained by hepatocellular levels of the amines or by their reactivity with GSH-BDA. Mercapturic acid derivatives of the spermidine cross-links were detected in the urine of furan-treated rats, which indicates that this metabolic pathway occurs in vivo. Their detection in furan-treated hepatocytes and in urine from furan-treated rats indicates that polyamines may play an important role in the toxicity of furan PMID:21842885
Gong, Biao; Li, Xiu; Bloszies, Sean; Wen, Dan; Sun, Shasha; Wei, Min; Li, Yan; Yang, Fengjuan; Shi, Qinghua; Wang, Xiufeng
2014-06-01
Nitric oxide (NO) and polyamines (PAs) are two kinds of important signal in mediating plant tolerance to abiotic stress. In this study, we observed that both NO and PAs decreased alkaline stress in tomato plants, which may be a result of their role in regulating nutrient balance and reactive oxygen species (ROS), thereby protecting the photosynthetic system from damage. Further investigation indicated that NO and PAs induced accumulation of each other. Furthermore, the function of PAs could be removed by a NO scavenger, cPTIO. On the other hand, application of MGBG, a PA synthesis inhibitor, did little to abolish the function of NO. To further elucidate the mechanism by which NO and PAs alleviate alkaline stress, the expression of several genes associated with abiotic stress was analyzed by qRT-PCR. NO and PAs significantly upregulated ion transporters such as the plasma membrane Na(+)/H(+) antiporter (SlSOS1), vacuolar Na(+)/H(+) exchanger (SlNHX1 and SlNHX2), and Na(+) transporter and signal components including ROS, MAPK, and Ca(2+) signal pathways, as well as several transcription factors. All of these play important roles in plant adaptation to stress conditions. Copyright © 2014 Elsevier Inc. All rights reserved.
Patel, C.; Xu, Z.; Shosha, E.; Xing, J.; Lucas, R.; Caldwell, R.W.; Caldwell, R.B.; Narayanan, S.P.
2016-01-01
Retinal vascular injury is a major cause of vision impairment in ischemic retinopathies. Insults such as hyperoxia, oxidative stress and inflammation contribute to this pathology. Previously, we showed that hyperoxia-induced retinal neurodegeneration is associated with increased polyamine oxidation. Here, we are studying the involvement of polyamine oxidases in hyperoxia-induced injury and death of retinal vascular endothelial cells. Newborn C57BL6/J mice were exposed to hyperoxia (70% O2) from postnatal day (P) 7 to 12 and were treated with the polyamine oxidase inhibitor MDL 72527 or vehicle starting at P6. Mice were sacrificed after different durations of hyperoxia and their retinas were analyzed to determine the effects on vascular injury, microglial cell activation, and inflammatory cytokine profiling. The results of this analysis showed that MDL 72527 treatment significantly reduced hyperoxia-induced retinal vascular injury and enhanced vascular sprouting as compared with the vehicle controls. These protective effects were correlated with significant decreases in microglial activation as well as levels of inflammatory cytokines and chemokines. In order to model the effects of polyamine oxidation in causing microglial activation in vitro, studies were performed using rat brain microvascular endothelial cells treated with conditioned-medium from rat retinal microglia stimulated with hydrogen peroxide. Conditioned-medium from activated microglial cultures induced cell stress signals and cell death in microvascular endothelial cells. These studies demonstrate the involvement of polyamine oxidases in hyperoxia-induced retinal vascular injury and retinal inflammation in ischemic retinopathy, through mechanisms involving cross-talk between endothelial cells and resident retinal microglia. PMID:27239699
Inhibition of polyamine and spermine oxidases by polyamine analogues.
Bianchi, Marzia; Polticelli, Fabio; Ascenzi, Paolo; Botta, Maurizio; Federico, Rodolfo; Mariottini, Paolo; Cona, Alessandra
2006-03-01
Polyamine oxidase (PAO) and spermine oxidase (SMO) are involved in the catabolism of polyamines--basic regulators of cell growth and proliferation. The discovery of selective inhibitors of PAO and SMO represents an important tool in studying the involvement of these enzymes in polyamine homeostasis and a starting point for the development of novel antineoplastic drugs. Here, a comparative study on murine PAO (mPAO) and SMO (mSMO) inhibition by the polyamine analogues 1,8-diaminooctane, 1,12-diaminododecane, N-prenylagmatine (G3), guazatine and N,N1-bis(2,3-butadienyl)-1,4-butanediamine (MDL72527) is reported. Interestingly, 1,12-Diaminododecane and G3 behave as specific inhibitors of mPAO, values of K(i) for mPAO inhibition being lower than those for mSMO inactivation by several orders of magnitude. The analysis of molecular models of mPAO and mSMO indicates a significant reduction of the hydrophobic pocket located in maize PAO (MPAO) at the wider catalytic tunnel opening. This observation provides a rationale to explain the lower affinity displayed by G3, guazatine and MDL72527 for mPAO and mSMO as compared to MPAO. The different behaviour displayed by 1,12-diaminododecane towards mPAO and mSMO reveals the occurrence of basic differences in the ligand binding mode of the two enzymes, the first enzyme interacting mainly with substrate secondary amino groups and the second one with substrate primary amino groups. Thus, the data reported here provide the basis for the development of novel and selective inhibitors able to discriminate between mammalian SMO and PAO activities.
Directed deposition of inorganic oxide networks on patterned polymer templates
NASA Astrophysics Data System (ADS)
Ford, Thomas James Robert
Inspired by nature, we have successfully directed the deposition of inorganic oxide materials on polymer templates via a combination of top-down and bottom-up fabrication methods. We have functionally mimicked the hierarchical silica exoskeletons of diatoms, where specialized proteins chaperone the condensation of silicic acid into nanoscale silica networks confined by microscopic vesicle walls. We replaced the proteins with functionally analogous polyamines and vesicles with lithographically defined polymer templates. We grafted the polyamines either to the surface or throughout the template by changing the template chemistry and altering our grafting strategy. Exposure to an inorganic oxide precursor solution led to electrostatic aggregation at the polyamine chains, catalyzing hydrolysis and condensation to form long-range inorganic oxide nanoparticle networks. Grafted to epoxy surfaces, swelling effects and the hyperbranched brush morphology lead to the formation of nanofruit features that generated thin, conformal inorganic coatings. When the polyamines were grafted throughout hydrogel templates, we obtained composite networks that yielded faithful inorganic replicas of the original patterns. By varying the polyamine chain length and combustion parameters, we controlled the nanoparticle size, morphology, and crystalline phase. The polyamine morphology affected the resulting inorganic network in both fabrication schemes and we could control the depostion over multiple length scales. Because our methods were compatible with a variety of lithographic methods, we were able to generate inorganic replicas of 1D, 2D, and 3D polymer structures. These may be used for a wide range of applications, including sensing, catalysis, photonic, phononic, photovoltaic, and others that require well-defined inorganic structures.
Sugiura, Koichi; Min, Jun Zhe; Toyo'oka, Toshimasa; Inagaki, Shinsuke
2008-09-26
The rapid, sensitive and simultaneous determination of six polyamines, i.e., ornithine (ORN), 1,3-diaminopropane (DAP), putrescine (PUT), cadaverine (CAD), spermidine (SPD) and spermine (SPM), in human hairs was performed by ultra-performance liquid chromatography (UPLC) with fluorescence (FL) detection and electrospray-ionization time-of-flight mass spectrometry (ESI-TOF-MS). The primary (-NH(2)) and secondary (-NH) amines in the polyamine structures were first labeled with 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F) at 60 degrees C for 30 min in the mixture of 0.1M borax (pH 9.3) and acetonitrile (CH(3)CN). The resulting derivatives were perfectly separated using an ACQUITY UPLC BEH C(18) column (1.7 microm, 100 mm x 2.1mm i.d.) by a gradient elution with a mixture of water-acetonitrile containing 0.1% formic acid (HCOOH). The separated polyamine derivatives were sensitively detected with both FL and TOF-MS. The detection limits in FL and TOF-MS were 11-86 and 2-5 fmol, respectively. However, the determination of several polyamines by FL detection was interfered with by endogenous substances in the hair. Therefore, the simultaneous determination in hair was carried out by the combination of UPLC separation and the ESI-TOF-MS detection. The structures of the polyamines were identified from the protonated-molecular ions [M+H](+) obtained from the TOF-MS measurement. A good linearity was achieved from the calibration curves, that was obtained by plotting the peak area ratios of the analytes relative to the internal standard (IS), i.e., 1,6-diaminohexane (DAH), against the injected amounts of each polyamine (0.05-50 pmol, r(2)>0.999). The proposed method was applied to the determination in the hairs of healthy volunteers. The mean concentrations of ORN, DAP, PUT, CAD, SPD and SPM in 1mg of human hairs (n=20) were 1.46, 0.18, 1.18, 0.11, 1.97 and 0.98 pmol, respectively. Because the proposed method provides a good mass accuracy and the trace detection of the polyamines in hair, this analytical technique seems to be applicable for the determination of various biological compounds in hair.
Oyanagui, Y
1984-02-01
Serotonin paw edema of mice and carrageenan paw edema of rats were inhibited by subcutaneously or orally administered certain polyamines. They must be given at least 2 h before serotonin challenge to get inhibitions which were blocked by the concomitant injections of cycloheximide. Thirty percent inhibitory dose (ID30) of polyamines (s.c.) 3 h before serotonin (s.c.) were: spermidine (8 mg/kg), spermine 28 mg/kg) and putrescine (55 mg/kg). Agmatine, cadaverine, ornithine, citrulline, lysine and arginine were not inhibitory even at 200 mg/kg. Three inhibitory polyamines were effective by oral administration but were not inhibitory by local administration into the paws. Intravenous injections of spermidine also required 2 h of lag period for inhibitions. Serotonin edema was inhibited by dexamethasone (1 mg/kg), prednisolone (1 mg/kg) or by superoxide dismutase (SOD, 5 mg/kg) in lag period requiring manner (s.c. and i.v.). High dose of cyclo-oxygenase inhibitors indomethacin and diclofenac sodium, lipo-oxygenase inhibitor BW755C (30 mg/kg s.c., respectively) and phospholipase A2 inhibitor quinacrine (100 mg/kg s.c.) failed to inhibit serotonin edema, suggesting that arachidonate metabolites are not participating in this model. ID30 of polyamines which were administered (s.c. and oral) to rats 3 h before carrageenan and determined at 3 h by paw weight were: spermidine (28 and 100 mg/kg), spermine (18 and 90 mg/kg) and putrescine (both greater than 200 mg/kg). Adrenalectomized rats responded to polyamines just as normal rats. Local vascular permeability, irritancy and acute toxicity were also tested in mice. Polyamines were proved to be glucocorticoid-type anti-inflammatory drugs. Polyamines may be mediators of glucocorticoids for the synthesis of the postulated vascular permeability inhibitory protein (called as 'vasoregulin' for convenience). Anti-inflammatory effect of glucocorticoid is recently explained by its capacity to induce phospholipase A2 inhibitory protein(s) (macrocortin or lipomodulin). However, this hypothesis has not yet been proved by in vivo experiment and our data suggest that there is induction by glucocorticoid of another kind of protein which does not inhibit phospholipase A2 activity.
The afferent pathways of discogenic low-back pain. Evaluation of L2 spinal nerve infiltration.
Nakamura, S I; Takahashi, K; Takahashi, Y; Yamagata, M; Moriya, H
1996-07-01
The afferent pathways of discogenic low-back pain have not been fully investigated. We hypothesised that this pain was transmitted mainly by sympathetic afferent fibres in the L2 nerve root, and in 33 patients we used selective local anaesthesia of this nerve. Low-back pain disappeared or significantly decreased in all patients after the injection. Needle insertion provoked pain which radiated to the low back in 23 patients and the area of skin hypoalgesia produced included the area of pre-existing pain in all but one. None of the nine patients with related sciatica had relief of that component of their symptoms. Our findings show that the main afferent pathways of pain from the lower intervertebral discs are through the L2 spinal nerve root, presumably via sympathetic afferents from the sinuvertebral nerves. Discogenic low-back pain should be regarded as a visceral pain in respect of its neural pathways. Infiltration of the L2 nerve is a useful diagnostic test and also has some therapeutic value.
[Polyamines and cell growth: specific aspects in Amoeba proteus and in certain cancer cell lines].
Dubois, J; Schenkel, E; Hanocq, M
1995-01-01
The differences between the metabolic schemes of polyamines can be the starting point to investigate the discovery of new antiparasitic or anticancer drugs which would be cell type specific. The studies, which were undertaken with the P388 cancer cells and Amoeba proteus, have shown that the pool of polyamine was very different in both cell types. Moreover, the cytotoxicity of putrescine, spermidine, spermine and 1-3 diaminopropane was found to be dependent of the activity of cell enzymes which could play a role to control cell proliferation by producing toxic metabolites.
Melvin, M A; Keir, H M
1978-01-01
Methylglyoxal bis(guanylhydrazone) (1,1'-[methylethanediylidine)dinitrilo]diguanidine) inhibited the growth of BHK-21/C13 cells in monolayer cultures. Accumulation of spermidine and spermine was inhibited, whereas the accumulation of putrescine was increased. The intracellular spermidine/spermine molar ratio decreased conly slightly after exposure of the cells to 20 micrometer-methylglyoxal bis(guanylhydrazone) for 1 day. Cells incubated in the presence of the drug released less polyamine into the culture medium that did control cells, the polyamine released consisting almost exclusively of spermidine, both free and as a conjugated form. PMID:697761
Polycatecholamide chelating agents
Weitl, Frederick L.; Raymond, Kenneth N.
1984-01-01
Novel polybenzamide compounds useful for in vitro or in vivo chelation are described. The compounds have the formula ##STR1## Polyamines are reacted with 2,3-dimethoxy benzoyl chloride unsubstituted or substituted with SO.sub.3 H, SO.sub.3 M, NO.sub.2, CO.sub.2 H or CO.sub.2 M as desired is reacted with a polyamine in an inert solvent then demethylated with BBr.sub.3 or BCl.sub.3 in an inert solvent. Where compounds symmetrically substituted on the terminal N's are desired, the polyamine is first reductively alkylated by reaction with an aldehyde or ketone and the resulting Schiff base is hydrogenated.
2015-01-01
Polycations are explored as carriers to deliver therapeutic nucleic acids. Polycations are conventionally pharmacological inert with the sole function of delivering therapeutic cargo. This study reports synthesis of a self-immolative polycation (DSS-BEN) based on a polyamine analogue drug N1,N11-bisethylnorspermine (BENSpm). The polycation was designed to function dually as a gene delivery carrier and a prodrug targeting dysregulated polyamine metabolism in cancer. Using a combination of NMR and HPLC, we confirm that the self-immolative polycation undergoes intracellular degradation into the parent drug BENSpm. The released BENSpm depletes cellular levels of spermidine and spermine and upregulates polyamine catabolic enzymes spermine/spermidine N1-acetyltransferase (SSAT) and spermine oxidase (SMO). The synthesized polycations form polyplexes with DNA and facilitate efficient transfection. Taking advantage of the ability of BENSpm to sensitize cancer cells to TNFα-induced apoptosis, we show that DSS-BEN enhances the cell killing activity of TNFα gene therapy. The reported findings validate DSS-BEN as a dual-function delivery system that can deliver a therapeutic gene and improve the outcome of gene therapy as a result of the intracellular degradation of DSS-BEN to BENSpm and the subsequent beneficial effect of BENSpm on dysregulated polyamine metabolism in cancer. PMID:25153488
Hydroxylamine derivatives for regulation of spermine and spermidine metabolism.
Khomutov, M A; Weisell, J; Hyvönen, M; Keinänen, T A; Vepsäläinen, J; Alhonen, L; Khomutov, A R; Kochetkov, S N
2013-12-01
The biogenic polyamines spermine, spermidine, and their precursor putrescine are present in micro-to-millimolar concentrations in all cell types and are vitally important for their normal growth. High intracellular content of spermine and spermidine determines the multiplicity of the cellular functions of the polyamines. Many of these functions are not well characterized at the molecular level, ensuring the ongoing development of this field of biochemistry. Tumor cells have elevated polyamine level if compared with normal cells, and this greatly stimulates the search for new opportunities to deplete the intracellular pool of spermine and spermidine resulting in decrease in cell growth and even cell death. O-Substituted hydroxylamines occupy their own place among chemical regulators of the activity of the enzymes of polyamine metabolism. Varying the structure of the alkyl substituent made it possible to obtain within one class of chemical compounds highly effective inhibitors and regulators of the activity of all the enzymes of putrescine, spermine and spermidine metabolism (with the exception of FAD-dependent spermine oxidase and acetylpolyamine oxidase), effectors of the polyamine transport system, and even actively transported in cells "proinhibitor" of ornithine decarboxylase. Some principles for the design of specific inhibitors of these enzymes as well as the peculiarities of cellular effects of corresponding O-substituted hydroxylamines are discussed.
Verkoelen, C F; Romijn, J C; Schroeder, F H; van Schalkwijk, W P; Splinter, T A
1988-04-08
A rapid and simple method, originally described by Redmond and Tseng [J. Chromatogr., 170 (1979) 479] was applied to the analysis of di- and polyamines in cultured human tumour cells and human tumour xenografts. Optimization of the procedures and evaluation of the characteristic features of the assay are described. The (modified) procedure employs precolumn derivatization with benzoyl chloride, extraction of the derivatives by chloroform, separation by reversed-phase high-performance liquid chromatography under isocratic conditions and detection by ultraviolet absorbance measurement at 229 nm. The complete analysis was accomplished within 10 min per sample. The detection limit was ca. 1 pmol. The intra- and inter-assay coefficients of variation were 2.5-4.4% and 3.4-13.1%, respectively. The presence of well known inhibitors of polyamine biosynthesis, such as DL-alpha-difluoromethylornithine and methylglyoxal bis(guanylhydrazone), did not interfere with the assay, and disturbance by cyclohexylamine could be avoided by changing the polarity of the mobile phase. The method proved to be very suitable because it is rapid, simple, requires a minimum of sample pretreatment, and still provides sufficient sensitivity to quantitate polyamines in relatively small amounts of cells (10(5) cells) or tumour tissues (less than 1 mg), even after treatment with inhibitors of polyamine biosynthesis.
Ziosi, Vanina; Bregoli, Anna Maria; Bonghi, Claudio; Fossati, Tiziana; Biondi, Stefania; Costa, Guglielmo; Torrigiani, Patrizia
2006-01-01
The time course of ethylene biosynthesis and perception was investigated in ripening peach fruit (Prunus persica) following treatments with the polyamines putrescine (Pu) and spermidine (Sd), and with aminoethoxyvinylglycine (AVG). Fruit treatments were performed in planta. Ethylene production was measured by gas chromatography, and polyamine content by high-performance liquid chromatography; expression analyses were performed by Northern blot or real-time polymerase chain reaction. Differential increases in the endogenous polyamine pool in the epicarp and mesocarp were induced by treatments; in both cases, ethylene production, fruit softening and abscission were greatly inhibited. The rise in 1-aminocyclopropane-1-carboxylate oxidase (PpACO1) mRNA was counteracted and delayed in polyamine-treated fruit, whereas transcript abundance of ethylene receptors PpETR1 (ethylene receptor 1) and PpERS1 (ethylene sensor 1) was enhanced at harvest. Transcript abundance of arginine decarboxylase (ADC) and S-adenosylmethionine decarboxylase (SAMDC) was transiently reduced in both the epicarp and mesocarp. AVG, here taken as a positive control, exerted highly comparable effects to those of Pu and Sd. Thus, in peach fruit, increasing the endogenous polyamine pool in the epicarp or in the mesocarp strongly interfered, both at a biochemical and at a biomolecular level, with the temporal evolution of the ripening syndrome.
Ethylglyoxal bis(guanylhydrazone) as an inhibitor of polyamine biosynthesis in L1210 leukemia cells.
Seppänen, P; Ruohola, H; Jänne, J
1984-04-16
Ethylglyoxal bis(guanylhydrazone), a close derivative of the known anti-cancer drug methylglyoxal bis(guanylhydrazone), is also a powerful inhibitor of S-adenosylmethionine decarboxylase (EC 4.1.1.50), the enzyme needed for the synthesis of spermidine and spermine. There were, however, marked differences between the ethyl and methyl derivatives of glyoxal bis(guanylhydrazone) when tested in cultured L1210 cells. The cellular accumulation of ethylglyoxal bis(guanylhydrazone) represented only a fraction (20-25%) of that of the methyl derivative. Moreover, polyamine depletion, which is known to strikingly stimulate the uptake of methylglyoxal bis(guanylhydrazone), decreased, if anything, the uptake of ethylglyoxal bis(guanylhydrazone) by L1210 cells. The compound produced spermidine and spermine depletion fully comparable to that achieved with methylglyoxal bis(guanylhydrazone) at micromolar concentrations. Ethylglyoxal bis(guanylhydrazone) was growth-inhibitory to L1210 cells and produced an additive antiproliferative action when used together with 2-difluoromethylornithine. Ethylglyoxal bis(guanylhydrazone) was distinctly less effective than methylglyoxal bis(guanylhydrazone) in releasing bound polyamines from isolated cell organelles in vitro. Ethylglyoxal bis(guanylhydrazone) was also devoid of the early and profound mitochondrial toxicity typical to methylglyoxal bis(guanylhydrazone). These findings may indicate that this compound is a more specific inhibitor of polyamine biosynthesis with less intracellular polyamine 'receptor-site' activity than methylglyoxal bis(guanylhydrazone).
Verbascoside Inhibits Promastigote Growth and Arginase Activity of Leishmania amazonensis.
Maquiaveli, Claudia C; Lucon-Júnior, João F; Brogi, Simone; Campiani, Giuseppe; Gemma, Sandra; Vieira, Paulo C; Silva, Edson R
2016-05-27
Verbascoside (1) is a phenylethanoid glycoside that has antileishmanial activity against Leishmania infantum and Leishmania donovani. In this study, we verified the activity of 1 on Leishmania amazonensis and arginase inhibition. Compound 1 showed an EC50 of 19 μM against L. amazonensis promastigotes and is a competitive arginase inhibitor (Ki = 0.7 μM). Docking studies were performed to assess the interaction of 1 with arginase at the molecular level. Arginase is an enzyme of the polyamine biosynthesis pathway that is important to parasite infectivity, and the results of our study suggest that 1 could be useful to develop new approaches for treating leishmaniasis.
The methionine salvage pathway in Bacillus subtilis
Sekowska, Agnieszka; Danchin, Antoine
2002-01-01
Background Polyamine synthesis produces methylthioadenosine, which has to be disposed of. The cell recycles it into methionine through methylthioribose (MTR). Very little was known about MTR recycling for methionine salvage in Bacillus subtilis. Results Using in silico genome analysis and transposon mutagenesis in B. subtilis we have experimentally uncovered the major steps of the dioxygen-dependent methionine salvage pathway, which, although similar to that found in Klebsiella pneumoniae, recruited for its implementation some entirely different proteins. The promoters of the genes have been identified by primer extension, and gene expression was analyzed by Northern blotting and lacZ reporter gene expression. Among the most remarkable discoveries in this pathway is the role of an analog of ribulose diphosphate carboxylase (Rubisco, the plant enzyme used in the Calvin cycle which recovers carbon dioxide from the atmosphere) as a major step in MTR recycling. Conclusions A complete methionine salvage pathway exists in B. subtilis. This pathway is chemically similar to that in K. pneumoniae, but recruited different proteins to this purpose. In particular, a paralogue or Rubisco, MtnW, is used at one of the steps in the pathway. A major observation is that in the absence of MtnW, MTR becomes extremely toxic to the cell, opening an unexpected target for new antimicrobial drugs. In addition to methionine salvage, this pathway protects B. subtilis against dioxygen produced by its natural biotope, the surface of leaves (phylloplane). PMID:12022921
The Photoconversion of Phytochrome Includes an Unproductive Shunt Reaction Pathway.
Buhrke, David; Kuhlmann, Uwe; Michael, Norbert; Hildebrandt, Peter
2018-03-05
Phytochromes are modular bimodal photoswitches that control gene expression for morphogenetic processes in plants. These functions are triggered by photoinduced conversions between the inactive and active states of the photosensory module, denoted as Pr and Pfr, respectively. In the present time-resolved resonance Raman spectroscopic study of bacterial representatives of this photoreceptor family, we demonstrate that these phototransformations do not represent linear processes but include a branching reaction back to the initial state, prior to (de)activation of the output module. Thus, only a fraction of the photoreceptors undergoing the phototransformations can initiate the downstream signaling process, consistent with phytochrome's function as a sensor for more durable changes of light conditions. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Block of high-threshold calcium channels by the synthetic polyamines sFTX-3.3 and FTX-3.3.
Norris, T M; Moya, E; Blagbrough, I S; Adams, M E
1996-10-01
A polyamine component of Agelenopsis aperta spider venom designated FTX is reported to be a selective antagonist of P-type calcium channels in the mammalian brain. Consequently, this component has frequently been used as a pharmacological tool to determine the presence, distribution, and function of P-type channels in physiological systems. We describe antagonism of calcium channels by the synthesized polyamine FTX-3.3, which has the proposed structure of natural FTX. We also examined a corresponding polyamine amide, sFTX-3.3. These polyamines are critically evaluated for antagonism of three high-threshold calcium channel subtypes in rat neurons through the use of the whole-cell patch-clamp technique. FTX-3.3 (IC50 = approximately 0.13 mM) is approximately twice as potent as sFTX-3.3 (IC50 = approximately 0.24 mM) against P-type channels and approximately 3-fold more potent against N-type channels (FTX-3.3, IC50 = approximately 0.24 mM; sFTX-3.3, IC50 = approximately 0.70 mM). Both polyamines also block L-type calcium channels with similar potencies. sFTX-3.3 (1 mM) and FTX-3.3 (0.5 mM) typically block 50% and 65% of Bay K8644-enhanced L-type current, respectively. Antagonism of each calcium channel subtype is voltage dependent, with less inhibition of Ba2+ currents at more-positive potentials. These data show that both sFTX-3.3 and FTX-3.3 antagonize P-, N-, and L-type calcium channels in mammalian Purkinje and superior cervical ganglia neurons with similar IC50 values.
Lenis, Yasser Y; Wang, Xiaoqiu; Tang, Wanjin; Wu, Guoyao; Bazer, Fuller W
2016-10-01
Embryonic survival requires histotrophic nutrition, including molecules secreted or transported into the uterine lumen by uterine epithelia. L-Arginine (Arg) is a common substrate for synthesis of nitric oxide, ornithine, proline, glutamate, creatinine, urea, polyamines and agmatine. Agmatine (Agm) is a product of arginine decarboxylation and it is a substrate for agmatinase for synthesis of putrescine and other polyamines in the ovine conceptus. Polyamines are essential for conceptus development. Therefore, this study compared effects of Arg and Agm on the behavior of ovine trophectoderm (oTr1) cells cultured in vitro. Arg, but not Agm, increased proliferation and migration of oTr1 cells, but neither Arg nor Agm affected cell adhesion. The total amount of IFNT in culture medium of oTr1 cells was increased by Arg, but Agm increased the IFNT production per oTr1 cell. Arg and Agm plus Arg decreased secretion of dopamine and norepinephrine by oTr1 cells. Agm upregulates expression of mRNAs SLC7A1, agmatinase and OAZ2 while the combination of Arg and Agm decreased expression of mRNAs for ODC1, SLC7A1, OAZ1 and OAZ3 by oTr1 cells. Although Agm does not stimulate proliferation, migration or adhesion of oTr1 cells or their secretion of catecholamines, Agm did increase transcription of SLC7A1, agmatinase and OAZ2 genes which would increase the capacity of oTr1 cells to produce polyamines. Collectively, our findings suggest a role for Arg and Agm in the regulation of transport of basic amino acids (including Arg), polyamine synthesis, and secretion of catecholamines by oTr1 cells.
Seppänen, P; Alhonen-Hongisto, L; Jänne, J
1980-09-01
Enzymic determinations of intracellular concentrations of methylglyoxal-bis(guanylhydrazone), an anticancer drug which inhibits the synthesis of the polyamines spermidine and spermine, in cultured tumor cells revealed that the drug was remarkably effectively concentrated inside the cell. A concentration gradient across the cell membrane as great as 500--1000-fold was formed in cells exposed to the drug for 1-2 days. An exposure of cultured Ehrlich ascites carcinoma cells to increasing concentrations of the drug indicated that the cells could tolerate intracellular concentrations up to 1 mM with only slight changes in their proliferation rate. Micromolar concentrations of spermidine or spermine, but not putrescine, effectively blocked the uptake of methylglyoxal-bis(guanylhydrazone) and reduced the intracellular concentration of the drug below the levels required for growth inhibition. Analysis of cellular polyamine contents in Ehrlich ascites cells exposed to rising concentrations of methylglyoxal-bis(guanylhydrazone) gave little support to the view that the drug-induced growth inhibition was solely produced by an intracellular polyamine deprivation. Not only was the uptake of the drug inhibited in the presence of spermidine and spermine, but it was likewise washed out by polyamines from the cells that had been previously exposed to the drug and then transferred into drug-free medium in the presence of polyamines. For the inhibition of methylglyoxal-bis(guanylhydrazone) uptake by amines, three or more amino/imino groups were apparently required, since low concentrations of aliphatic diamines were either without any effect (short-chain diamines) or only marginally prevented (long-chain diamines) the uptake of the drug. High concentrations of Mg2+ ions, however, markedly inhibited the transport of the drug into Ehrlich ascites tumor cells.
Kim, Jin Sik; Lee, Jin; Chung, Hai Won; Choi, Han; Paik, Sang Gi; Kim, In Gyu
2006-09-01
Methylglyoxal-bis(guanylhydrazone) (MGBG), a polyamine analogue, has been known to inhibit the biosynthesis of polyamines, which are important in cell proliferation. We showed that MGBG treatment significantly affected γ-radiation-induced cell cycle transition (G(1)/G(0)→S→G(2)/M) and thus γ-radiation-induced cell death. As determined by micronuclei and comet assay, we showed that it sensitized the cytotoxic effect induced by γ-radiation. One of the reasons is that polyamine depletion by MGBG treatment did not effectively protect against the chemical (OH) or physical damage to DNA caused by γ-radiation. Through in vitro experiment, we confirmed that DNA strand breaks induced by γ-radiation was prevented more effectively in the presence of polyamines (spermine and spermidine) than in the absence of polyamines. MGBG also blocks the cell cycle transition caused by γ-radiation (G(2) arrest), which helps protect cells by allowing time for DNA repair before entry into mitosis or apoptosis, via the down regulation of cyclin D1, which mediates the transition from G(1) to S phase of cell cycle, and ataxia telangiectasia mutated, which is involved in the DNA sensing, repair and cell cycle check point. Therefore, the abrogation of G(2) arrest sensitizes cells to the effect of γ-radiation. As a result, γ-radiation-induced cell death increased by about 2.5-3.0-fold in cells treated with MGBG. However, exogenous spermidine supplement partially relieved this γ-radiation-induced cytotoxicity and cell death. These findings suggest a potentially therapeutic strategy for increasing the cytotoxic efficacy of γ-radiation.
Molecular strategies of the Caenorhabditis elegans dauer larva to survive extreme desiccation.
Erkut, Cihan; Vasilj, Andrej; Boland, Sebastian; Habermann, Bianca; Shevchenko, Andrej; Kurzchalia, Teymuras V
2013-01-01
Massive water loss is a serious challenge for terrestrial animals, which usually has fatal consequences. However, some organisms have developed means to survive this stress by entering an ametabolic state called anhydrobiosis. The molecular and cellular mechanisms underlying this phenomenon are poorly understood. We recently showed that Caenorhabditis elegans dauer larva, an arrested stage specialized for survival in adverse conditions, is resistant to severe desiccation. However, this requires a preconditioning step at a mild desiccative environment to prepare the organism for harsher desiccation conditions. A systems approach was used to identify factors that are activated during this preconditioning. Using microarray analysis, proteomics, and bioinformatics, genes, proteins, and biochemical pathways that are upregulated during this process were identified. These pathways were validated via reverse genetics by testing the desiccation tolerances of mutants. These data show that the desiccation response is activated by hygrosensation (sensing the desiccative environment) via head neurons. This leads to elimination of reactive oxygen species and xenobiotics, expression of heat shock and intrinsically disordered proteins, polyamine utilization, and induction of fatty acid desaturation pathway. Remarkably, this response is specific and involves a small number of functional pathways, which represent the generic toolkit for anhydrobiosis in plants and animals.
Muscle mitohormesis promotes cellular survival via serine/glycine pathway flux.
Ost, Mario; Keipert, Susanne; van Schothorst, Evert M; Donner, Verena; van der Stelt, Inge; Kipp, Anna P; Petzke, Klaus-Jürgen; Jove, Mariona; Pamplona, Reinald; Portero-Otin, Manuel; Keijer, Jaap; Klaus, Susanne
2015-04-01
Recent studies on mouse and human skeletal muscle (SM) demonstrated the important link between mitochondrial function and the cellular metabolic adaptation. To identify key compensatory molecular mechanisms in response to chronic mitochondrial distress, we analyzed mice with ectopic SM respiratory uncoupling in uncoupling protein 1 transgenic (UCP1-TG) mice as model of muscle-specific compromised mitochondrial function. Here we describe a detailed metabolic reprogramming profile associated with mitochondrial perturbations in SM, triggering an increased protein turnover and amino acid metabolism with induced biosynthetic serine/1-carbon/glycine pathway and the longevity-promoting polyamine spermidine as well as the trans-sulfuration pathway. This is related to an induction of NADPH-generating pathways and glutathione metabolism as an adaptive mitohormetic response and defense against increased oxidative stress. Strikingly, consistent muscle retrograde signaling profiles were observed in acute stress states such as muscle cell starvation and lipid overload, muscle regeneration, and heart muscle inflammation, but not in response to exercise. We provide conclusive evidence for a key compensatory stress-signaling network that preserves cellular function, oxidative stress tolerance, and survival during conditions of increased SM mitochondrial distress, a metabolic reprogramming profile so far only demonstrated for cancer cells and heart muscle. © FASEB.
Molecular Strategies of the Caenorhabditis elegans Dauer Larva to Survive Extreme Desiccation
Erkut, Cihan; Vasilj, Andrej; Boland, Sebastian; Habermann, Bianca; Shevchenko, Andrej; Kurzchalia, Teymuras V.
2013-01-01
Massive water loss is a serious challenge for terrestrial animals, which usually has fatal consequences. However, some organisms have developed means to survive this stress by entering an ametabolic state called anhydrobiosis. The molecular and cellular mechanisms underlying this phenomenon are poorly understood. We recently showed that Caenorhabditis elegans dauer larva, an arrested stage specialized for survival in adverse conditions, is resistant to severe desiccation. However, this requires a preconditioning step at a mild desiccative environment to prepare the organism for harsher desiccation conditions. A systems approach was used to identify factors that are activated during this preconditioning. Using microarray analysis, proteomics, and bioinformatics, genes, proteins, and biochemical pathways that are upregulated during this process were identified. These pathways were validated via reverse genetics by testing the desiccation tolerances of mutants. These data show that the desiccation response is activated by hygrosensation (sensing the desiccative environment) via head neurons. This leads to elimination of reactive oxygen species and xenobiotics, expression of heat shock and intrinsically disordered proteins, polyamine utilization, and induction of fatty acid desaturation pathway. Remarkably, this response is specific and involves a small number of functional pathways, which represent the generic toolkit for anhydrobiosis in plants and animals. PMID:24324795
Gonzalez-Esquerra, R; Leeson, S
2006-08-01
An experiment was designed to investigate the effect of Arg, Lys, Met, and environmental temperature on broiler performance and associated changes in duodenal and pancreatic polyamines. Two groups of 26-d-old Ross male broilers raised under thermoneutral (TN) conditions were reallocated to 4 rooms kept at heat stress (HS) or TN. Birds were fed equimolar amounts of 2-hydroxy-4-(methylthio) butanoic acid (HMB) or DL-Met (DLM) at requirement levels with Arg:Lys at 0.95 or 1.40. Twelve replicates of 4 birds were offered each diet ad libitum. Body weight gain, efficiency of dietary CP accretion (CPE), feed intake, and feed conversion ratio were ascertained from 26 to 33 d and from 34 to 47 d of age. One bird per cage was killed at 33 and 47 d, and samples of duodenum and pancreas were assayed for putrescine, spermidine, and spermine (Spm), together with estimates of duodenal villus height. From 26 to 33 d, birds fed HMB performed better than those fed DLM, but only at TN conditions. From 34 to 47 d, feeding HMB tended to optimize CPE when added to diets high in Arg. However, lower CPE was obtained when HMB was added to low-Arg diets, whereas birds fed DLM were unaffected by these treatments (P < 0.10). Methionine source, Arg:Lys, or both affected the concentrations of duodenal and pancreatic polyamines, with some changes correlating with performance variables during HS (P > 0.05). It was found that HS caused lower tissue spermidine (P < 0.001) and higher pancreatic Spm (P = 0.08) from 34 to 47 d. Putrescine concentrations were affected by diet and HS, depending on tissue and experimental period. Pancreatic Spm correlated negatively with changes in CPE influenced by Arg:Lys by Met source interaction in chronically heat-stressed birds. The possible association between polyamine metabolism and some of the effects of the Arg:Lys by Met source interaction observed in chronically stressed birds deserves further investigation.
Mono- and multimeric ferrocene congeners of quinoline-based polyamines as potential antiparasitics
USDA-ARS?s Scientific Manuscript database
A series of mono- and multimeric polyamine-containing ferrocenyl complexes bearing a quinoline motif were prepared. The complexes were characterised by standard techniques. The molecular structure of the monomeric salicylaldimine derivative was elucidated using single crystal X-ray diffraction and w...
Kallio, A; Jänne, J
1983-01-01
Treatment of mice bearing L1210 leukaemia with 2-difluoromethylornithine, a specific inhibitor of ornithine decarboxylase (EC 4.1.1.17), produced a profound depletion of putrescine and spermidine in the tumour cells. Sequential combination of methylglyoxal bis(guanylhydrazone), an inhibitor of adenosylmethionine decarboxylase (EC 4.1.1.50), with difluoromethylornithine largely reversed the polyamine depletion and led to a marked accumulation of cadaverine in the tumour cells. Experiments carried out with the combination of difluoromethylornithine and aminoguanidine, a potent inhibitor of diamine oxidase (EC 1.4.3.6), indicated that the methylglyoxal bis(guanylhydrazone)-induced reversal of polyamine depletion was mediated by the known inhibition of diamine oxidase by the diguanidine. In spite of the normalization of the tumour cell polyamine pattern upon administration of methylglyoxal bis(guanylhydrazone) to difluoromethylornithine-treated animals, the combination of these two drugs produced a growth-inhibitory effect not achievable with either of the compounds alone. PMID:6411077
Activation of ADP-ribosyltransferase in polyamine-depleted mammalian cells.
Wallace, H M; Gordon, A M; Keir, H M; Pearson, C K
1984-01-01
Mammalian fibroblasts were cultured in the presence of alpha-methylornithine and/or methylglyoxal bis(guanylhydrazone), which inhibit the synthesis of polyamines. This led to a decrease in the cellular content of the polyamines spermine and spermidine by up to 60% when the cells were grown in the presence of both drugs together. The activity of the chromatin-associated enzyme ADP-ribosyltransferase was enhanced 2-3-fold in the drug-treated cells when measured in cells subsequently rendered permeable to exogenous NAD+, the substrate for the transferase. This is a novel and surprising observation, since the transferase is invariably activated by the addition of polyamines to a suitable incubation system such as permeabilized cells, isolated nuclei or the purified enzyme. We found no evidence that the activation was due to the appearance of DNA strand breaks, by using a variety of procedures including both neutral [the 'nucleoid' technique of Cook & Brazell [(1975) J. Cell Sci. 19, 261-279; (1976) J. Cell Sci. 22, 287-302
Penesyan, Anahit; Kumar, Sheemal S.; Kamath, Karthik; Shathili, Abdulrahman M.; Venkatakrishnan, Vignesh; Krisp, Christoph; Packer, Nicolle H.; Molloy, Mark P.; Paulsen, Ian T.
2015-01-01
The opportunistic pathogen Pseudomonas aeruginosa is among the main colonizers of the lungs of cystic fibrosis (CF) patients. We have isolated and sequenced several P. aeruginosa isolates from the sputum of CF patients and compared them with each other and with the model strain PAO1. Phenotypic analysis of CF isolates showed significant variability in colonization and virulence-related traits suggesting different strategies for adaptation to the CF lung. Genomic analysis indicated these strains shared a large set of core genes with the standard laboratory strain PAO1, and identified the genetic basis for some of the observed phenotypic differences. Proteomics revealed that in a conventional laboratory medium PAO1 expressed 827 proteins that were absent in the CF isolates while the CF isolates shared a distinctive signature set of 703 proteins not detected in PAO1. PAO1 expressed many transporters for the uptake of organic nutrients and relatively few biosynthetic pathways. Conversely, the CF isolates expressed a narrower range of transporters and a broader set of metabolic pathways for the biosynthesis of amino acids, carbohydrates, nucleotides and polyamines. The proteomic data suggests that in a common laboratory medium PAO1 may transport a diverse set of “ready-made” nutrients from the rich medium, whereas the CF isolates may only utilize a limited number of nutrients from the medium relying mainly on their own metabolism for synthesis of essential nutrients. These variations indicate significant differences between the metabolism and physiology of P. aeruginosa CF isolates and PAO1 that cannot be detected at the genome level alone. The widening gap between the increasing genomic data and the lack of phenotypic data means that researchers are increasingly reliant on extrapolating from genomic comparisons using experimentally characterized model organisms such as PAO1. While comparative genomics can provide valuable information, our data suggests that such extrapolations may be fraught with peril. PMID:26431321
Polycatecholamide chelating agents
Weitl, F.L.; Raymond, K.N.
1984-04-10
Novel polybenzamide compounds useful for in vitro or in vivo chelation are described. The compounds have the formula given in patent. Polyamines are reacted with 2,3-dimethoxy benzoyl chloride unsubstituted or substituted with SO[sub 3]H, SO[sub 3]M, NO[sub 2], CO[sub 2]H or CO[sub 2]M as desired is reacted with a polyamine in an inert solvent then demethylated with BBr[sub 3] or BCl[sub 3] in an inert solvent. Where compounds symmetrically substituted on the terminal N's are desired, the polyamine is first reductively alkylated by reaction with an aldehyde or ketone and the resulting Schiff base is hydrogenated. No Drawings
Novel polycatecholamide chelating agents
Weitl, F.L.; Raymond, K.N.
1981-08-24
Novel polybenzamide compounds useful for in vitro or in vivo chelation are described. Formulas of the compounds are given. To prepare them polyamines are reacted with 2,3-dimethoxy benzoyl chloride unsubstituted or substituted with SO/sub 3/H, SO/sub 3/M, NO/sub 2/, CO/sub 2/H or CO/sub 2/M as desired is reacted with a polyamine in an inert solvent then demethylated with BBr/sub 3/ or BCl/sub 3/ in an inert solvent. Where compounds symmetrically substituted on the terminal N's are desired, the polyamine is first reductively alkylated by reaction with an aldehyde or ketone and the resulting Schiff base is hydrogenated.
Role of polyamines in somatic embryogenesis
S.C. Minocha; R. Minocha
1995-01-01
The aliphatic amines putrescine, spermidine, and spermine are present in all living organisms. Since the demonstration of "an essential nutritional function" for putrescine in the bacterium Hemophilus parainfluenzae (Herbst and Snell 1948), polyamines have attracted a great deal of attention from workers in diverse fields of the life...
Polyamines: Biomolecules with diverse functions in plant and human health and disease
USDA-ARS?s Scientific Manuscript database
The literature abounds with solid evidence that affirms the ubiquitous presence of biogenic amines - polyamines, particularly spermidine and spermine, in all living cells together with their indispensable roles in many biochemical and physiological processes beneficial to plants as well as human hea...
5 CFR 315.713 - Conversion based on service in a Pathways Program under part 362 of this chapter.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Conversion based on service in a Pathways... in a Pathways Program under part 362 of this chapter. (a) Agency authority. An agency may convert to..., the following Pathways Participants: (1) An Intern who has satisfactorily completed the Internship...
5 CFR 315.713 - Conversion based on service in a Pathways Program under part 362 of this chapter.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Conversion based on service in a Pathways... in a Pathways Program under part 362 of this chapter. (a) Agency authority. An agency may convert to..., the following Pathways Participants: (1) An Intern who has satisfactorily completed the Internship...
Masalova, O V; Lesnova, E I; Samokhvalov, E I; Permyakova, K Yu; Ivanov, A V; Kochetkov, S N; Kushch, A A
2017-01-01
Hepatitis C virus (HCV) induces the expression of the genes of proinflammatory cytokines, the excessive production of which may cause cell death, and contribute to development of liver fibrosis and hepatocarcinoma. The relationship between cytokine production and metabolic disorders in HCV-infected cells remains obscure. The levels of biogenic polyamines, spermine, spermidine, and their precursor putrescine, may be a potential regulator of these processes. The purpose of the present work was to study the effects of the compounds which modulate biogenic polyamines metabolism on cytokine production and HCV proteins expression. Human hepatocarcinoma Huh7.5 cells have been transfected with the plasmids that encode HCV proteins and further incubated with the following low-molecular compounds that affect different stages of polyamine metabolism: (1) difluoromethylornithine (DFMO), the inhibitor of ornithine decarboxylase, the enzyme that catalyzes the biosynthesis of polyamines; (2) N,N'-bis(2,3-butane dienyl)-1,4-diaminobutane (MDL72.527), the inhibitor of proteins involved in polyamine degradation; and (3) synthetic polyamine analog N^(I),N^(II)-diethylnorspermine (DENSpm), an inducer of polyamine degradation enzyme. The intracellular accumulation and secretion of cytokines (IL-6, IL-1β, TNF-α, and TGF-β) was assessed by immunocytochemistry and in the immunoenzyme assay, while the cytokine gene expression was studied using reverse transcription and PCR. The effects of the compounds under analysis on the expression of HCV proteins were analyzed using the indirect immunofluorescence with anti-HCV monoclonal antibodies. It has been demonstrated that, in cells transfected with HCV genes, DFMO reduces the production of three out of four tested cytokines, namely, TNF-α and TGF-β in cells that express HCV core, Е1Е2, NS3, NS5A, and NS5B proteins, and IL-1β in the cells that express HCV core, Е1Е2, and NS3 proteins. MDL72527 and DENSpm decreased cytokine production to a lesser extent. Incubation with DFMO led to a 28-32% decrease in the number of cells expressing NS5B or NS5A, both of which are key components of the HCV replication complex. The results obtained in the work indicate that a further detailed study of the antiviral activity of DFMO is required in order to assess its potential as an anti-hepatitis C therapeutic agent.
Increased integrity of white matter pathways after dual n-back training.
Salminen, Tiina; Mårtensson, Johan; Schubert, Torsten; Kühn, Simone
2016-06-01
Dual n-back WM training has been shown to produce broad transfer effects to different untrained cognitive functions. The task is demanding to the cognitive system because it includes a bi-modal (auditory and visual) dual-task component. A previous WM training study showed increased white matter integrity in the parietal lobe as well as the anterior part of the corpus callosum after visual n-back training. We investigated dual n-back training-related changes in white matter pathways. We anticipated dual n-back training to increase white matter integrity in pathways that connect brain regions related to WM processes. Additionally, we hypothesized that dual n-back training would produce more brain-wide white matter changes than single n-back training because of the involvement of two modalities and the additional dual-task coordination component of the task. The dual n-back training group showed increased white matter integrity (reflected as increased fractional anisotropy, FA) after training. The effects were mostly left lateralized as compared with changes from pretest to posttest in the passive and active control groups. Additionally, significant effects were observed in the anterior part of the corpus callosum, when the training group was compared with the passive control group. There were no changes in pretest to posttest FA changes between the passive and active control groups. The results therefore show that dual n-back training produces increased integrity in white matter pathways connecting different brain regions. The results are discussed in reference to the bi-modal dual-task component of the training task. Copyright © 2016 Elsevier Inc. All rights reserved.
Snezhkina, Anastasiya V; Krasnov, George S; Lipatova, Anastasiya V; Sadritdinova, Asiya F; Kardymon, Olga L; Fedorova, Maria S; Melnikova, Nataliya V; Stepanov, Oleg A; Zaretsky, Andrew R; Kaprin, Andrey D; Alekseev, Boris Y; Dmitriev, Alexey A; Kudryavtseva, Anna V
2016-01-01
Colorectal cancer is one of the most common cancers in the world. It is well known that the chronic inflammation can promote the progression of colorectal cancer (CRC). Recently, a number of studies revealed a potential association between colorectal inflammation, cancer progression, and infection caused by enterotoxigenic Bacteroides fragilis (ETBF). Bacterial enterotoxin activates spermine oxidase (SMO), which produces spermidine and H2O2 as byproducts of polyamine catabolism, which, in turn, enhances inflammation and tissue injury. Using qPCR analysis, we estimated the expression of SMOX gene and ETBF colonization in CRC patients. We found no statistically significant associations between them. Then we selected genes involved in polyamine metabolism, metabolic reprogramming, and inflammation regulation and estimated their expression in CRC. We observed overexpression of SMOX, ODC1, SRM, SMS, MTAP, c-Myc, C/EBPβ (CREBP), and other genes. We found that two mediators of metabolic reprogramming, inflammation, and cell proliferation c-Myc and C/EBPβ may serve as regulators of polyamine metabolism genes (SMOX, AZIN1, MTAP, SRM, ODC1, AMD1, and AGMAT) as they are overexpressed in tumors, have binding site according to ENCODE ChIP-Seq data, and demonstrate strong coexpression with their targets. Thus, increased polyamine metabolism in CRC could be driven by c-Myc and C/EBPβ rather than ETBF infection.
Snezhkina, Anastasiya V.; Lipatova, Anastasiya V.; Sadritdinova, Asiya F.; Kardymon, Olga L.; Fedorova, Maria S.; Kaprin, Andrey D.
2016-01-01
Colorectal cancer is one of the most common cancers in the world. It is well known that the chronic inflammation can promote the progression of colorectal cancer (CRC). Recently, a number of studies revealed a potential association between colorectal inflammation, cancer progression, and infection caused by enterotoxigenic Bacteroides fragilis (ETBF). Bacterial enterotoxin activates spermine oxidase (SMO), which produces spermidine and H2O2 as byproducts of polyamine catabolism, which, in turn, enhances inflammation and tissue injury. Using qPCR analysis, we estimated the expression of SMOX gene and ETBF colonization in CRC patients. We found no statistically significant associations between them. Then we selected genes involved in polyamine metabolism, metabolic reprogramming, and inflammation regulation and estimated their expression in CRC. We observed overexpression of SMOX, ODC1, SRM, SMS, MTAP, c-Myc, C/EBPβ (CREBP), and other genes. We found that two mediators of metabolic reprogramming, inflammation, and cell proliferation c-Myc and C/EBPβ may serve as regulators of polyamine metabolism genes (SMOX, AZIN1, MTAP, SRM, ODC1, AMD1, and AGMAT) as they are overexpressed in tumors, have binding site according to ENCODE ChIP-Seq data, and demonstrate strong coexpression with their targets. Thus, increased polyamine metabolism in CRC could be driven by c-Myc and C/EBPβ rather than ETBF infection. PMID:27433286
Filippova, Ekaterina V; Weigand, Steven; Osipiuk, Jerzy; Kiryukhina, Olga; Joachimiak, Andrzej; Anderson, Wayne F
2015-11-06
The spermidine N-acetyltransferase SpeG is a dodecameric enzyme that catalyzes the transfer of an acetyl group from acetyl coenzyme A to polyamines such as spermidine and spermine. SpeG has an allosteric polyamine-binding site and acetylating polyamines regulate their intracellular concentrations. The structures of SpeG from Vibrio cholerae in complexes with polyamines and cofactor have been characterized earlier. Here, we present the dodecameric structure of SpeG from V. cholerae in a ligand-free form in three different conformational states: open, intermediate and closed. All structures were crystallized in C2 space group symmetry and contain six monomers in the asymmetric unit cell. Two hexamers related by crystallographic 2-fold symmetry form the SpeG dodecamer. The open and intermediate states have a unique open dodecameric ring. This SpeG dodecamer is asymmetric except for the one 2-fold axis and is unlike any known dodecameric structure. Using a fluorescence thermal shift assay, size-exclusion chromatography with multi-angle light scattering, small-angle X-ray scattering analysis, negative-stain electron microscopy and structural analysis, we demonstrate that this unique open dodecameric state exists in solution. Our combined results indicate that polyamines trigger conformational changes and induce the symmetric closed dodecameric state of the protein when they bind to their allosteric sites. Copyright © 2015. Published by Elsevier Ltd.
Sotomayor, Verónica; Lascano, Cecilia; de D'Angelo, Ana María Pechen; Venturino, Andrés
2012-09-01
Organophosphorus pesticides (OPs) are widely applied in the Alto Valle of Río Negro and Neuquén, Argentina, due to intensive fruit growing. Amphibians are particularly sensitive to environmental pollution, and OPs may transiently accumulate in ponds and channels of the region during their reproductive season. Organophosphorus pesticide exposure may alter amphibian embryonic development and the reproductive success of autochthonous species. In the present study, embryos of the common toad Rhinella arenarum were employed to assess developmental alterations and to study polyamine metabolism, which is essential to normal growth, as a possible target underlying the effects of the OP chlorpyrifos. As the duration of chlorpyrifos exposure increased and embryonic development progressed, the median lethal concentration (LC50) values decreased, and the percentage of malformed embryos increased. Developmental arrest was also observed and several morphological alterations were recorded, such as incomplete and abnormal closure of the neural tube, dorsal curvature of the caudal fin, reduction of body size and caudal fin length, atrophy, and edema. An early decrease in ornithine decarboxylase (ODC) activity and polyamine levels was also observed in embryos exposed to chlorpyrifos. The decrease in polyamine contents in tail bud embryos might be a consequence of the reduction in ODC activity. The alteration of polyamine metabolism occurred before embryonic growth was interrupted and embryonic malformations were observed and may be useful as a biomarker in environmental studies. Copyright © 2012 SETAC.
Zhou, Cheng; Liu, Zhi; Zhu, Lin; Ma, Zhongyou; Wang, Jianfei; Zhu, Jian
2016-10-25
Melatonin has recently been demonstrated to play important roles in the regulation of plant growth, development, and abiotic and biotic stress responses. However, the possible involvement of melatonin in Fe deficiency responses and the underlying mechanisms remained elusive in Arabidopsis thaliana . In this study, Fe deficiency quickly induced melatonin synthesis in Arabidopsis plants. Exogenous melatonin significantly increased the soluble Fe content of shoots and roots, and decreased the levels of root cell wall Fe bound to pectin and hemicellulose, thus alleviating Fe deficiency-induced chlorosis. Intriguingly, melatonin treatments induced a significant increase of nitric oxide (NO) accumulation in roots of Fe-deficient plants, but not in those of polyamine-deficient ( adc2-1 and d-arginine-treated) plants. Moreover, the melatonin-alleviated leaf chlorosis was blocked in the polyamine- and NO-deficient ( nia1nia2noa1 and c-PTIO-treated) plants, and the melatonin-induced Fe remobilization was largely inhibited. In addition, the expression of some Fe acquisition-related genes, including FIT1 , FRO2 , and IRT1 were significantly up-regulated by melatonin treatments, whereas the enhanced expression of these genes was obviously suppressed in the polyamine- and NO-deficient plants. Collectively, our results provide evidence to support the view that melatonin can increase the tolerance of plants to Fe deficiency in a process dependent on the polyamine-induced NO production under Fe-deficient conditions.
Wang, Wei; Liu, Ji-Hong
2016-08-18
Polyamine oxidase (PAO) is a key enzyme catalyzing polyamine catabolism leading to H2O2 production. We previously demonstrated that Citrus sinensis contains six putative PAO genes, but their functions are not well understood. In this work, we reported functional elucidation of CsPAO4 in polyamine catabolism and salt stress response. CsPAO4 was localized to the apoplast and used both spermidine (Spd) and spermine (Spm) as substrates for terminal catabolism. Transgenic plants overexpressing CsPAO4 displayed prominent increase in PAO activity, concurrent with marked decrease of Spm and Spd and elevation of H2O2. Seeds of transgenic lines displayed better germination when compared with wild type (WT) under salt stress. However, both vegetative growth and root elongation of the transgenic lines were prominently inhibited under salt stress, accompanied by higher level of H2O2 and more conspicuous programmed cell death (PCD). Exogenous supply of catalase (CAT), a H2O2 scavenger, partially recovered the vegetative growth and root elongation. In addition, spermine inhibited root growth of transgenic plants. Taken together, these data demonstrated that CsPAO4 accounts for production of H2O2 causing oxidative damages under salt stress and that down-regulation of a PAO gene involved in polyamine terminal catabolism may be an alternative approach for improving salt stress tolerance.
Renaud, Stéphanie; Corcé, Vincent; Cannie, Isabelle; Ropert, Martine; Lepage, Sylvie; Loréal, Olivier; Deniaud, David; Gaboriau, François
2015-08-01
Tumor cell growth requires large iron quantities and the deprivation of this metal induced by synthetic metal chelators is therefore an attractive method for limiting the cancer cell proliferation. The antiproliferative effect of the Quilamine HQ1-44, a new iron chelator vectorized toward tumor cells by a polyamine chain, is related to its high selectivity for the Polyamine Transport System (PTS), allowing its preferential uptake by tumoral cells. The difference in PTS activation between healthy cells and tumor cells enables tumor cells to be targeted, whereas the strong dependence of these cells on iron ensures a secondary targeting. Here, we demonstrated in vitro that HQ1-44 inhibits DNA synthesis and cell proliferation of HCT116 cells by modulating the intracellular metabolism of both iron and polyamines. Moreover, in vivo, in xenografted athymic nude mice, we found that HQ1-44 was as effective as cis-platin in reducing HCT116 tumor growth, without its side effects. Furthermore, as suggested by in vitro data, the depletion in exogenous or endogenous polyamines, known to activate the PTS, dramatically enhanced the antitumor efficiency of HQ1-44. These data support the need for further studies to assess the value of HQ1-44 as an adjuvant treatment in cancer. Copyright © 2015 Elsevier Inc. All rights reserved.
Glucocorticoids and Polyamine Inhibitors Synergize to Kill Human Leukemic CEM Cells1
Miller, Aaron L; Johnson, Betty H; Medh, Rheem D; Townsend, Courtney M; Thompson, E Brad
2002-01-01
Abstract Glucocorticoids are well-known apoptotic agents in certain classes of lymphoid cell malignancies. Reduction of intracellular polyamine levels by use of inhibitors that block polyamine synthesis slows or inhibits growth of many cells in vitro. Several such inhibitors have shown efficacy in clinical trials, though the toxicity of some compounds has limited their usefulness. We have tested the effects of combinations of the glucocorticoid dexamethasone (Dex) and two polyamine inhibitors, difluoromethylornithine (DFMO) and methyl glyoxal bis guanylhydrazone (MGBG), on the clonal line of human acute lymphoblastic leukemia cells, CEM-C7-14. Dex alone kills these cells, though only after a delay of at least 24 hours. We also evaluated a partially glucocorticoid-resistant c-Myc-expressing CEM-C7-14 clone. We show that Dex downregulates ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine synthesis. Pretreatment with the ODC inhibitor DFMO, followed by addition of Dex, enhances steroid-evoked kill slightly. The combination of pretreatment with sublethal concentrations of both DFMO and the inhibitor of S-adenosylmethionine decarboxylase, MGBG, followed by addition of Dex, results in strong synergistic cell kill. Both the rapidity and extent of cell kill are enhanced compared to the effects of Dex alone. These results suggest that use of such combinations in vivo may result in apoptosis of malignant cells with lower overall toxicity. PMID:11922393
Filippova, Ekaterina V.; Weigand, Steven J.; Osipiuk, Jerzy; ...
2015-09-26
The spermidine N-acetyltransferase SpeG is a dodecameric enzyme that catalyzes the transfer of an acetyl group from acetyl coenzyme A to polyamines such as spermidine and spermine. SpeG has an allosteric polyamine-binding site and acetylating polyamines regulate their intracellular concentrations. The structures of SpeG from Vibrio cholerae in complexes with polyamines and cofactor have been characterized earlier. Here, we present the dodecameric structure of SpeG from V. cholerae in a ligand-free form in three different conformational states: open, intermediate and closed. All structures were crystallized in C2 space group symmetry and contain six monomers in the asymmetric unit cell. Twomore » hexamers related by crystallographic 2-fold symmetry form the SpeG dodecamer. The open and intermediate states have a unique open dodecameric ring. This SpeG dodecamer is asymmetric except for the one 2-fold axis and is unlike any known dodecameric structure. Using a fluorescence thermal shift assay, size-exclusion chromatography with multi-angle light scattering, small-angle X-ray scattering analysis, negative-stain electron microscopy and structural analysis, we demonstrate that this unique open dodecameric state exists in solution. As a result, our combined results indicate that polyamines trigger conformational changes and induce the symmetric closed dodecameric state of the protein when they bind to their allosteric sites.« less
Yuan, Jian-Jun; Kimitsuka, Nobuo; Jin, Ren-Hua
2013-04-24
The synthesis of polysilsesquioxanes coating with controllable one-dimensional nanostructure on substrates remains a major long-term challenge by conventional solution-phase method. The hydrolytic polycondensation of organosilanes in solution normally produces a mixture of incomplete cages, ladderlike, and network structures, resulting in the poor control of the formation of specific nanostructure. This paper describes a simple aqueous process to synthesize nanofilament-based coatings of polysilsesquioxanes possessing various organo-functional groups (for example, thiol, methyl, phenyl, vinyl, and epoxy). We utilized a self-assembled nanostructured polyamine layer as a biomimetically catalytic scaffold/template to direct the formation of one-dimensional nanofilament of polysilsesquioxanes by temporally and spatially controlled hydrolytic polycondensation of organosilane. The surface nanostructure and morphology of polysilsesquioxane coating could be modulated by changing hydrolysis and condensation reaction conditions, and the orientation of nanofilaments of polysilsesquioxanes on substrates could be controlled by simply adjusting the self-assembly conditions of polyamine layer. The nanostructure and polyamine@polysilsesquioxane hybrid composition of nanofilament-based coatings were examined by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The template role of nanostructured polyamine layer for the formation of polysilsesquioxane nanofilament was confirmed by combining thin film X-ray diffraction (XRD) and XPS measurements. Moreover, these nanotextured coatings with various organo-functional groups could be changed into superhydrophobic surfaces after surface modification with fluorocarbon molecule.
Fatima, Tahira; Sobolev, Anatoly P; Teasdale, John R; Kramer, Matthew; Bunce, Jim; Handa, Avtar K; Mattoo, Autar K
Metabolomics provides a view of endogenous metabolic patterns not only during plant growth, development and senescence but also in response to genetic events, environment and disease. The effects of the field environment on plant hormone-specific metabolite profiles are largely unknown. Few studies have analyzed useful phenotypes generated by introducing single or multiple gene events alongside the non-engineered wild type control at field scale to determine the robustness of the genetic trait and its modulation in the metabolome as a function of specific agroecosystem environments. We evaluated the influence of genetic background (high polyamine lines; low methyl jasmonate line; low ethylene line; and isogenic genotypes carrying double transgenic events) and environments (hairy vetch, rye, plastic black mulch and bare soil mulching systems) on the metabolomic profile of isogenic reverse genetic mutations and selected mulch based cropping systems in tomato fruit. Net photosynthesis and fruit yield were also determined. NMR spectroscopy was used for quantifying metabolites that are central to primary metabolism. We analyzed both the first moment (means) of metabolic response to genotypes and agroecosystems by traditional univariate/multivariate methods, and the second moment (covariances) of responses by creating networks that depicted changes in correlations of paired metabolites. This particular approach is novel and was necessary because our experimental material yielded highly variable metabolic responses that could not be easily understood using the traditional analytical approaches for first moment statistics. High endogenous spermidine and spermine content exhibited strong effects on amino acids, Krebs cycle intermediates and energy molecules (ADP + ATP) in ripening fruits of plants grown under different agroecosystem environments. The metabolic response to high polyamine genotypes was similar to the response to hairy vetch cover crop mulch; supported by the pattern of changes in correlation between metabolites. Changes in primary metabolites of genotypes mutated for the deficiency of ethylene or methyl jasmonate were unique under all growth conditions and opposite of high polyamine genotype results. The high polyamine trait was found to dominate the low ethylene and low jasmonate mutations under field conditions. For several metabolites low ethylene and low methyl jasmonate genotypes had an inverse relationship. Collectively, these results affirm that interactions between metabolite pathways and growth environments are affected by genotype, and influence the metabolite quality of a crop. This study portrays how metabolite relationships change, both in mean and in correlation, under different genotypic and environmental conditions. Although these networks are surprisingly dynamic, we also find examples of selectively conserved associations.
Sahin, Ceren; Albayrak, Ozgur; Akdeniz, Tuğba F; Akbulut, Zeynep; Yanikkaya Demirel, Gulderen; Aricioglu, Feyza
2016-10-01
The activation of Nod-like receptor protein 3 (NLRP3) has lately been implicated in stress and depression as an initiator mechanism required for the production of interleukin (IL)-1β and IL-18. Agmatine, an endogenous polyamine widely distributed in mammalian brain, is a novel neurotransmitter/neuromodulator, with antistress, anxiolytic and antidepressant-like effects. In this study, we examined the effect of exogenously administered agmatine on NLRP3 inflammasome pathway/cytokine responses in rats exposed to restraint stress for 7 days. The rats were divided into three groups: stress, stress+agmatine (40 mg/kg; i.p.) and control groups. Agmatine significantly down-regulated the gene expressions of all stress-induced NLRP3 inflammasome components (NLRP3, NF-κB, PYCARD, caspase-1, IL-1β and IL-18) in the hippocampus and prefrontal cortex (PFC) and reduced pro-inflammatory cytokine levels not only in both brain regions, but also in serum. Stress-reduced levels of IL-4 and IL-10, two major anti-inflammatory cytokines, were restored back to normal by agmatine treatment in the PFC. The findings of the present study suggest that stress-activated NLRP3 inflammasome and cytokine responses are reversed by an acute administration of agmatine. Whether antidepressant-like effect of agmatine can somehow, at least partially, be mediated by the inhibition of NLRP3 inflammasome cascade and relevant inflammatory responses requires further studies in animal models of depression. © 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).
SEDIMENT-MEDIATED REDUCTION OF 2,4,6-TRINITROTOLUENE AND FATE OF THE RESULTING AROMATIC (POLY)AMINES
2,4,6-Trinitrotoluene is a major surface and subsurface contaminant found at numerous munitions production and storage facilities. The reductive transformation of 2,4,6-trinitrotoluene (TNT) to aromatic (poly)amines and the consequent fate of these products were studied in anaer...
Li, Guiyang; Zhang, Biao; Yan, Jun; Wang, Zhonggang
2016-01-21
This work reveals that furfural and 2-thenaldehyde can readily react with melamine via "one-step" polycondensation to yield hyper-cross-linked sulfur-, nitrogen- and oxygen-rich microporous polyaminals with promising applications in adsorption of gases and toxic organic vapors.
USDA-ARS?s Scientific Manuscript database
Transgenic tomato (Solanum lycopersicum) lines over-expressing yeast spermidine synthase (ySpdSyn), an enzyme involved in polyamine (PA) biosynthesis, were developed. These transgenic lines accumulate higher levels of spermidine (Spd) than the wild type plants and were examined for responses to the...
USDA-ARS?s Scientific Manuscript database
Polyamines are biogenic polycationic compounds implicated in a number of processes including plant cell division, cell elongation, flowering, fruit set and development, fruit ripening, senescence and responses to abiotic stresses. Comparatively, little is known about their role in plant-microbe int...
Zhang, Xue; Zhang, Chenxi; Sun, Xiaomin; Kang, Lingyan; Zhao, Yan
2015-01-01
As a widely used antimicrobial additive in daily consumption, attention has been paid to the degradation and conversion of triclosan for a long time. The quantum chemistry calculation and the canonical variational transition state theory are employed to investigate the mechanism and kinetic property. Besides addition and abstraction, oxidation pathways and further conversion pathways are also considered. The OH radicals could degrade triclosan to phenols, aldehydes, and other easily degradable substances. The conversion mechanisms of triclosan to the polychlorinated dibenzopdioxin and furan (PCDD/Fs) and polychlorinated biphenyls (PCBs) are clearly illustrated and the toxicity would be strengthened in such pathways. Single radical and diradical pathways are compared to study the conversion mechanism of dichlorodibenzo dioxin (DCDD). Furthermore, thermochemistry is discussed in detail. Kinetic property is calculated and the consequent ratio of kadd/ktotal and kabs/ktotal at 298.15 K are 0.955 and 0.045, respectively. Thus, the OH radical addition reactions are predominant, the substitute position of OH radical on triclosan is very important to generate PCDD and furan, and biradical is also a vital intermediate to produce dioxin. PMID:25867482
Characterization and redox regulation of Plasmodium falciparum methionine adenosyltransferase.
Pretzel, Jette; Gehr, Marina; Eisenkolb, Maike; Wang, Lihui; Fritz-Wolf, Karin; Rahlfs, Stefan; Becker, Katja; Jortzik, Esther
2016-12-01
As a methyl group donor for biochemical reactions, S-adenosylmethionine plays a central metabolic role in most organisms. Depletion of S-adenosylmethionine has downstream effects on polyamine metabolism and methylation reactions, and is an effective way to combat pathogenic microorganisms such as malaria parasites. Inhibition of both the methylation cycle and polyamine synthesis strongly affects Plasmodium falciparum growth. Despite its central position in the methylation cycle, not much is currently known about P. falciparum methionine adenosyltransferase (PfalMAT). Notably, however, PfalMAT has been discussed as a target of different redox regulatory modifications. Modulating the redox state of critical cysteine residues is a way to regulate enzyme activity in different pathways in response to changes in the cellular redox state. In the present study, we optimized an assay for detailed characterization of enzymatic activity and redox regulation of PfalMAT. While the presence of reduced thioredoxin increases the activity of the enzyme, it was found to be inhibited upon S-glutathionylation and S-nitrosylation. A homology model and site-directed mutagenesis studies revealed a contribution of the residues Cys52, Cys113 and Cys187 to redox regulation of PfalMAT by influencing its structure and activity. This phenomenon connects cellular S-adenosylmethionine synthesis to the redox state of PfalMAT and therefore to the cellular redox homeostasis. © The Authors 2016. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.
Physiological and molecular implications of plant polyamine metabolism during biotic interactions
Jiménez-Bremont, Juan F.; Marina, María; Guerrero-González, María de la Luz; Rossi, Franco R.; Sánchez-Rangel, Diana; Rodríguez-Kessler, Margarita; Ruiz, Oscar A.; Gárriz, Andrés
2014-01-01
During ontogeny, plants interact with a wide variety of microorganisms. The association with mutualistic microbes results in benefits for the plant. By contrast, pathogens may cause a remarkable impairment of plant growth and development. Both types of plant–microbe interactions provoke notable changes in the polyamine (PA) metabolism of the host and/or the microbe, being each interaction a complex and dynamic process. It has been well documented that the levels of free and conjugated PAs undergo profound changes in plant tissues during the interaction with microorganisms. In general, this is correlated with a precise and coordinated regulation of PA biosynthetic and catabolic enzymes. Interestingly, some evidence suggests that the relative importance of these metabolic pathways may depend on the nature of the microorganism, a concept that stems from the fact that these amines mediate the activation of plant defense mechanisms. This effect is mediated mostly through PA oxidation, even though part of the response is activated by non-oxidized PAs. In the last years, a great deal of effort has been devoted to profile plant gene expression following microorganism recognition. In addition, the phenotypes of transgenic and mutant plants in PA metabolism genes have been assessed. In this review, we integrate the current knowledge on this field and analyze the possible roles of these amines during the interaction of plants with microbes. PMID:24672533
Walczak, Karl; Chen, Yikai; Karp, Christoph; Beeman, Jeffrey W; Shaner, Matthew; Spurgeon, Joshua; Sharp, Ian D; Amashukeli, Xenia; West, William; Jin, Jian; Lewis, Nathan S; Xiang, Chengxiang
2015-02-01
A fully integrated solar-driven water-splitting system comprised of WO3 /FTO/p(+) n Si as the photoanode, Pt/TiO2 /Ti/n(+) p Si as the photocathode, and Nafion as the membrane separator, was simulated, assembled, operated in 1.0 M HClO4 , and evaluated for performance and safety characteristics under dual side illumination. A multi-physics model that accounted for the performance of the photoabsorbers and electrocatalysts, ion transport in the solution electrolyte, and gaseous product crossover was first used to define the optimal geometric design space for the system. The photoelectrodes and the membrane separators were then interconnected in a louvered design system configuration, for which the light-absorbing area and the solution-transport pathways were simultaneously optimized. The performance of the photocathode and the photoanode were separately evaluated in a traditional three-electrode photoelectrochemical cell configuration. The photocathode and photoanode were then assembled back-to-back in a tandem configuration to provide sufficient photovoltage to sustain solar-driven unassisted water-splitting. The current-voltage characteristics of the photoelectrodes showed that the low photocurrent density of the photoanode limited the overall solar-to-hydrogen (STH) conversion efficiency due to the large band gap of WO3 . A hydrogen-production rate of 0.17 mL hr(-1) and a STH conversion efficiency of 0.24 % was observed in a full cell configuration for >20 h with minimal product crossover in the fully operational, intrinsically safe, solar-driven water-splitting system. The solar-to-hydrogen conversion efficiency, ηSTH , calculated using the multiphysics numerical simulation was in excellent agreement with the experimental behavior of the system. The value of ηSTH was entirely limited by the performance of the photoelectrochemical assemblies employed in this study. The louvered design provides a robust platform for implementation of various types of photoelectrochemical assemblies, and can provide an approach to significantly higher solar conversion efficiencies as new and improved materials become available. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Geerts, R; van Ginkel, C G; Plugge, C M
2017-04-01
The biodegradation of N-alkyl polypropylene polyamines (NAPPs) was studied using pure and mixed cultures to enable read-across of ready biodegradability test results. Two Pseudomonas spp. were isolated from activated sludge with N-oleyl alkyl propylene diamine and N-coco alkyl dipropylene triamine, respectively. Both strains utilized all NAPPs tested as the sole source of carbon, nitrogen and energy for growth. Mineralization of NAPPs was independent of the alkyl chain length and the size of the polyamine moiety. NAPPs degraded in closed bottle tests (CBTs) using both river water and activated sludge. However, ready biodegradability of NAPPs with alkyl chain lengths of 16-18 carbon atoms and polyamine moieties with three and four nitrogen atoms could not be demonstrated. Biodegradation in the CBT was hampered by their limited bioavailability, making assessment of the true ready biodegradability of these highly adsorptive surfactants impossible. All NAPPs are therefore classified as readily biodegradable through read-across. Read-across is justified by the broad substrate specificity of NAPP-degrading microorganisms, their omnipresence and the mineralization of NAPPs.
Enzymes loaded chitosan/coconut fibre/zinc oxide nanoparticles strip for polyamine determination.
Hooda, Vinita; Archita
2018-01-15
Most often, the immobilized enzyme based quantification is an attractive alternative to other chromatographic, electrochemical and mass spectrometry based methods due to its specificity and simplicity. In the present study, polyamine oxidase specific for spermine and spermidine and diamine oxidase specific for putrescine, were co-immobilized onto a novel chitosan/coconut fibre/zinc oxide nanoparticles (CS/CF/nZnO) hybrid support to yield a polyamine sensing strip. The strip worked optimally at pH 7.0, temperature 25°C and 6min of incubation time. Pretty good values for kinetic constants Km app (6.60mM), Vmax (17.69μmol/min mg protein) and kcat app (1987.64s -1 ) as well as for thermal (<50 % activity retained at 40°C), storage (half life-40days) and operational stabilities (<90 % activity retained after 20 reuses) were obtained. The strip was employed for polyamine determination in some of the locally grown fruit and vegetables and the results were found to be comparable, reliable and reproducible. Copyright © 2017 Elsevier Ltd. All rights reserved.
Insights on ornithine decarboxylase silencing as a potential strategy for targeting retinoblastoma.
Muthukumaran, Sivashanmugam; Bhuvanasundar, Renganathan; Umashankar, Vetrivel; Sulochana, K N
2018-02-01
Ornithine Decarboxylase (ODC) is a key enzyme involved in polyamine synthesis and is reported to be up regulated in several cancers. However, the effect of ODC gene silencing in retinoblastoma is to be understood for utilization in therapeutic applications. Hence, in this study, a novel siRNA (small interference RNA) targeting ODC was designed and validated in Human Y79 retinoblastoma cells for its effects on intracellular polyamine levels, Matrix Metalloproteinase 2 & 9 activity and Cell cycle. The designed siRNA showed efficient silencing of ODC mRNA expression and protein levels in Y79 cells. It also showed significant reduction of intracellular polyamine levels and altered levels of oncogenic LIN28b expression. By this study, a regulatory loop is proposed, wherein, ODC silencing in Y79 cells to result in decreased polyamine levels, thereby, leading to altered protein levels of Lin28b, MMP-2 and MMP-9, which falls in line with earlier studies in neuroblastoma. Thus, by this study, we propose ODC silencing as a prospective strategy for targeting retinoblastoma. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Chilivery, Rakesh; Rana, Rohit Kumar
2017-01-25
A polyamine-mediated bioinspired strategy to assemble Keggin-type phosphomolybdic acid (PMA) clusters is demonstrated for the fabrication of microcapsule (MC) structures with unique surface textures. It involves supramolecular aggregation of polyamines with multivalent anions, which then allows the assembly of negatively charged PMA into MCs in an aqueous medium under ambient conditions. Resembling the role of polyamines in biosilicification of diatoms, the polyamine-anion interaction is shown to be the key for the assembly process. It not only provides structural stability but also facilitates an interesting transition from a smooth to a wrinkled surface alongside a change in the Keggin form to its lacunary form depending on the pH of the medium. Moreover, the presence of isolated PMA units in the hybrid structure enables them to be active in catalyzing the aerobic oxidation of alkenes under solvent-free conditions with better selectivity and reusability. Hence, the assembly approach represents an effective way for heterogenization of PMA-based materials and is expected to find considerable application in the wider hybrid-cluster field.
Cockerell, Steven R.; Rutkovsky, Alex C.; Zayner, Josiah P.; Cooper, Rebecca E.; Porter, Lindsay R.; Pendergraft, Sam S.; Parker, Zach M.; McGinnis, Marcus W.
2014-01-01
The polyamines norspermidine and spermidine are among the environmental signals that regulate Vibrio cholerae biofilm formation. The effects of these polyamines are mediated by NspS, a member of the bacterial periplasmic solute binding protein superfamily. Almost all members of this superfamily characterized to date are components of ATP-binding cassette-type transporters involved in nutrient uptake. Consequently, in the current annotation of the V. cholerae genome, NspS has been assigned a function in transport. The objective of this study was to further characterize NspS and investigate its potential role in transport. Our results support a role for NspS in signal transduction in response to norspermidine and spermidine, but not their transport. In addition, we provide evidence that these polyamine signals are processed by c-di-GMP signalling networks in the cell. Furthermore, we present comparative genomics analyses which reveal the presence of NspS-like proteins in a variety of bacteria, suggesting that periplasmic ligand binding proteins may be widely utilized for sensory transduction. PMID:24530989
Changes in polyamine levels in various organs of Bombyx mori during its life cycle.
Hamana, K; Matsuzaki, S; Inoue, K
1984-06-01
Polyamines in various organs of larval, pupal, and moth stages of Bombyx mori, were assayed by high-performance ion-exchange chromatography and paper and thin-layer chromatography. Putrescine and spermidine were especially abundant in the silk gland, gonads, mucous gland, and sucking stomach; spermine was also present in them, but at much lower concentrations. Both norspermidine and norspermine were detected in almost all organs examined, while their precursor 1,3-diaminopropane was found only in a limited number of organs. Low concentrations of sym-homospermidine were observed in the silk gland and ovary. Cadaverine content was particularly high in the mucous gland which contained diapause eggs and the sucking stomach. Diapause eggs contained much higher levels of cadaverine than non-diapause eggs. The concentrations of most polyamines in the silk glands remained rather constant during the larval stage, and decreased markedly at the pupal stage. Polyamines in gonads, in contrast, did not decrease at the pupal stage, but putrescine, diaminopropane, and norspermidine rather increased during the pupal and moth stages.
Morris, D R; Jorstad, C M; Seyfried, C E
1977-09-01
The cancer chemotherapeutic drug, methylglyoxal bis(guanylhydrazone), inhibits the synthesis of spermidine and spermine, but allows continued putrescine production in small lymphocytes stimulated by concanavalin A. DNA replication in these cells is inhibited 50% while the synthesis of protein and RNA continues normally. When excess putrescine accumulation in the presence of methylglyoxal bis(guanylhydrazone) was inhibited with alpha-methylornithine, a competitive inhibitor of ornithine decarboxylase, the inhibition of DNA replication was accentuated, with still no effect on protein or RNA synthesis. No inhibition of DNA synthesis by the combination of alpha-methylornithine and methylglyoxal bis(guanylhydrazone) was observed when the inhibitors were added after accumulation of cellular polyamines. In addition, inhibition was reversed by exogenous putrescine, spermidine, or spermine. We conclude that putrescine can fulfill in part the role normally played by spermidine and spermine in DNA replication, and that blocking putrescine synthesis in the presence of methylglyoxal bis(guanylhydrazone) amplifies the polyamine requirement. The implications of this with regard to polyamine synthesis as a site of chemotherapy are discussed.
Caldarera, C M; Casti, A; Guarnier, C; Moruzzi, G
1975-10-01
The relationship between polyamines and RNA synthesis was studied by considering the action of spermine on histone acetylation in perfused heart. In addition, the effect of methylglyoxal bis(guanylhydrazone), inhibitor of putrescine-activated S-adenosylmethionine decarboxylase activity, on RNA and polyamine specific radioactivity and on acetylation of histone fractions was also investigated in perfused heart. Different concentrations of spermine and/or methylglyoxas bis(guanylhydrazone) were injected into the heart, 15 min after beginning the perfusion. The results demonstrate that spermine stimulates the specific radioactivity of RNA of subcellular fractions. Acetylation of the arginine-rich histone fractions, involved in the regulation of RNA transcription, is enhanced by spermine. The perfusion with methylglyoxal bis(guanylhydrazone) causes a decrease in the specific radioactivity of polyamines and RNA, and in acetylation of histone fractions. However, spermine is able to reverse the methylglyoxal bis(guanylhydrazone) inhibition when injected simultaneously. From these results we may assume a possible role for spermine in the regulation of RNA transcription.
Caldarera, C M; Casti, A; Guarnier, C; Moruzzi, G
1975-01-01
The relationship between polyamines and RNA synthesis was studied by considering the action of spermine on histone acetylation in perfused heart. In addition, the effect of methylglyoxal bis(guanylhydrazone), inhibitor of putrescine-activated S-adenosylmethionine decarboxylase activity, on RNA and polyamine specific radioactivity and on acetylation of histone fractions was also investigated in perfused heart. Different concentrations of spermine and/or methylglyoxas bis(guanylhydrazone) were injected into the heart, 15 min after beginning the perfusion. The results demonstrate that spermine stimulates the specific radioactivity of RNA of subcellular fractions. Acetylation of the arginine-rich histone fractions, involved in the regulation of RNA transcription, is enhanced by spermine. The perfusion with methylglyoxal bis(guanylhydrazone) causes a decrease in the specific radioactivity of polyamines and RNA, and in acetylation of histone fractions. However, spermine is able to reverse the methylglyoxal bis(guanylhydrazone) inhibition when injected simultaneously. From these results we may assume a possible role for spermine in the regulation of RNA transcription. PMID:1212228
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rastogi, R.; Davies, P.J.
1991-01-01
The fruit of the Alcobaca landrace of tomato (Lycopersicon esculentum Mill.) have prolonged keeping qualities (determined by the allele alc) and contain three times as much putrescine as the standard Rutgers variety (Alc) at the ripe stage. Polyamine metabolism and biosynthesis were compared in fruit from Rutgers and Rutgers-alc-a near isogenic line possessing the allele alc, at four different stages of ripening. The levels of soluble polyamine conjugates as well as wall bound polyamines in the pericarp tissue and jelly were very low or nondetectable in both genotypes. The increase in putrescine content in alc pericarp is not related tomore » normal ripening as it occurred with time and whether or not the fruit ripened. Pericarp discs of both normal and alc fruit showed a decrease in the metabolism of (1,4-{sup 14}C)putrescine and (terminal labeled-{sup 3}H)spermidine with ripening, but there were no significant differences between the two genotypes. The activity of ornithine decarboxylase was similar in the fruit pericarp of the two lines. Arginine decarboxylase activity decreased during ripening in Rutgers but decreased and rose again in Rutgers-alc fruit, and as a result it was significantly higher in alc fruit than in the normal fruit at the ripe stage. The elevated putrescine levels in alc fruit appear, therefore, to be due to an increase in the activity of arginine decarboxylase.« less
Tolerance and efficacy of a polyamine-deficient diet for the treatment of perioperative pain.
Estebe, Jean-Pierre; Degryse, Cécile; Rezzadori, Gilles; Dimache, Florin; Daccache, Georges; Le Naoures, Alain; Belbachir, Anissa; Schoeffler, Pierre; Sérandour, Anne-Laure
2017-04-01
Polyamines have been identified as pain agonists and interact with N-methyl-D-aspartate receptors. A prospective, randomized, multicenter, and blinded phase II clinical trial was conducted to evaluate a polyamine-deficient diet for the treatment of perioperative pain in patients during spinal surgery. All analyses followed the intention-to-treat principle. The trial was designed to evaluate the dose-ranging effect of a low polyamine diet with respect to a total (group 1) or partial (group 2) polyamine diet on perioperative pain (7 d before and 5 d after surgery). Pain (numerical scale at rest and motion), quality of life questionnaires (Brief Pain Inventory, EIFEL questionnaire, and Short Form-12 acute questionnaire), and tolerance of and compliance with the nutritional program were measured. Compliance (preoperatively: 100% in group 1 and 83% in group 2; postoperatively: 83% in group 1 and 71% in group 2) and tolerance were good. After 7 d following the diet before surgery, decreased pain was observed in group 1 whereas no effect was observed in group 2 (P = 0.144). This analgesic effect became significant in group 1 in the subgroup of patients with initial high levels of pain (NS ≥ 4) at rest (P = 0.03) and during motion (P = 0.011). Quality of life was significantly improved in group 1 (P = 0.0465). In the postoperative period, pain was significantly decreased in group 1 compared to group 2 at rest (P = 0.022) and during motion (P = 0.029). The effect was significantly better on patients with higher initial pain both at rest (P = 0.013) and during motion (P = 0.005) in group 1 compared to group 2. Suppression of polyamines from the diet offers a nutrition-based treatment option for perioperative pain reduction independent of and complementary to typical analgesic approaches. Copyright © 2016 Elsevier Inc. All rights reserved.
Song, Hou-Pan; Li, Ru-Liu; Zhou, Chi; Cai, Xiong; Huang, Hui-Yong
2015-01-15
Atractylodes macrocephala Koidz (AMK), a valuable traditional Chinese herbal medicine, has been widely used in clinical practice for treating patients with disorders of the digestive system. AMK has shown noteworthy promoting effect on improving gastrointestinal function and immunity, which might represent a promising candidate for the treatment of intestinal mucosa injury. The aim of this study was to investigate the efficacy of AMK on intestinal mucosal restitution and the underlying mechanisms via intestinal epithelial (IEC-6) cell migration model. A cell migration model of IEC-6 cells was induced by a single-edge razor blade along the diameter of the cell layers in six-well polystyrene plates. After wounding, the cells were grown in control cultures and in cultures containing spermidine (5μM, SPD, reference drug), alpha-difluoromethylornithine (2.5mM, DFMO, polyamine inhibitor), AMK (50, 100, and 200mg/L), DFMO plus SPD and DFMO plus AMK for 12h. The polyamines content was detected by high-performance liquid chromatography (HPLC) with pre-column derivatization. The Rho mRNAs expression levels were assessed by Q-RT-PCR. The Rho and non-muscle myosin II proteins expression levels were analyzed by Western blot. The formation and distribution of non-muscle myosin II stress fibers were monitored with immunostaining techniques using specific antibodies and observed by confocal microscopy. Cell migration assay was carried out using inverted microscope and the Image-Pro Plus software. All of these indexes were used to evaluate the effectiveness of AMK. (1) Treatment with AMK caused significant increases in cellular polyamines content and Rho mRNAs and proteins expression levels, as compared to control group. Furthermore, AMK exposure increased non-muscle myosin II protein expression levels and formation of non-muscle myosin II stress fibers, and resulted in an acceleration of cell migration in IEC-6 cells. (2) Depletion of cellular polyamines by DFMO resulted in a decrease of cellular polyamines levels, Rho mRNAs and proteins expression, non-muscle myosin II protein formation and distribution, thereby inhibiting IEC-6 cell migration. AMK not only reversed the inhibitory effects of DFMO on the polyamines content, Rho mRNAs and proteins expression, non-muscle myosin II protein formation and distribution, but also restored cell migration to control levels. The results obtained from this study revealed that AMK significantly stimulates the migration of IEC-6 cells through a polyamine dependent mechanism, which could accelerate the healing of intestinal injury. These findings suggest the potential value of AMK in curing intestinal diseases characterized by injury and ineffective repair of the intestinal mucosa in clinical practice. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tan, Eric C.D.
This paper presents a comparative techno-economic analysis of four emerging conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with specific focus on pathways utilizing oxygenated intermediates. The processing steps include: biomass-to-syngas via indirect gasification, gas cleanup, conversion of syngas to alcohols/oxygenates followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation.
Zhang, Xue; Zhang, Chenxi; Sun, Xiaomin; Kang, Lingyan; Zhao, Yan
2015-04-10
As a widely used antimicrobial additive in daily consumption, attention has been paid to the degradation and conversion of triclosan for a long time. The quantum chemistry calculation and the canonical variational transition state theory are employed to investigate the mechanism and kinetic property. Besides addition and abstraction, oxidation pathways and further conversion pathways are also considered. The OH radicals could degrade triclosan to phenols, aldehydes, and other easily degradable substances. The conversion mechanisms of triclosan to the polychlorinated dibenzopdioxin and furan (PCDD/Fs) and polychlorinated biphenyls (PCBs) are clearly illustrated and the toxicity would be strengthened in such pathways. Single radical and diradical pathways are compared to study the conversion mechanism of dichlorodibenzo dioxin (DCDD). Furthermore, thermochemistry is discussed in detail. Kinetic property is calculated and the consequent ratio of k add/k total and k abs/k total at 298.15 K are 0.955 and 0.045, respectively. Thus, the OH radical addition reactions are predominant, the substitute position of OH radical on triclosan is very important to generate PCDD and furan, and biradical is also a vital intermediate to produce dioxin.
Polyamine levels during the development of zygotic and somatic embryos of Pinus radiata
Rakesh Minocha; Dale R. Smith; Cathie Reeves; Kevin D. Steele; Subhash C. Minocha
1999-01-01
Changes in the cellular content of three polyamines (putrescine, spermidine and spermine) were compared at different stages of development in zygotic and somatic embryos of Pinus radiata D. Don. During embryo development, both the zygotic and the somatic embryos showed a steady increase in spermidine content, with either a small decrease or no...
Andrew F. Page; Sridev Mohapatra; Rakesh Minocha; Subhash C. Minocha
2007-01-01
We have studied the effects of overproduction of putrescine (Put) via transgenic expression of a mouse ornithine decarboxylase (ODC) gene on the expression of native genes for four enzymes involved in polyamine biosynthesis in hybrid poplar (Populus nigra x maximowiczii) cells. An examination of the transcript levels of arginine...
USDA-ARS?s Scientific Manuscript database
Distribution of biogenic amines – the diamine putrescine (Put), triamine spermidine (Spd), and tetraamine spermine (Spm) - differs between species with Put and Spd being particularly abundant and Spm the least abundant in plant cells. These amines are important for cell viability and their intracel...
USDA-ARS?s Scientific Manuscript database
The effects of biotic and abiotic stresses on changes in amino acids and polyamine levels in Satsuma orange (Citrus unshiu; cultivar Owari) leaves were investigated. Asian citrus psyllids (Diaphorina citri (Kuwayama) (ACP) infestation was used to induce biotic stress while a water deficit was impos...
NASA Astrophysics Data System (ADS)
Shen, Zhi; Qin, Qi; Liao, Xiali; Yang, Bo
2017-12-01
The inclusion complexation behaviors of glycyrrhetic acid (CTA) with four polyamine-modified β-cyclodextrins (CDs) have been investigated by 1H and 2D NMR, thermal gravimetric analysis, X-ray power diffraction and scanning electron microscopy. The results showed that Glycyrrhetic acid was encapsulated into the cavity of cyclodextrin to form the complexes with 1:1 stoichiometry. The water solubility of GTA was significantly enhanced by inclusion complexation with polyamine-modified β-cyclodextrins. The calculated IC50 values indicated that the antitumor activities of inclusion complexes were better than that of GTA. Satisfactory aqueous solubility, along with high thermal stability of inclusion complexes will be potentially useful for their application on the formulation design of natural medicine.
Nitrogen recycling during phenylpropanoid metabolism in sweet potato tubers
NASA Technical Reports Server (NTRS)
Singh, S.; Lewis, N. G.; Towers, G. H.
1998-01-01
In the first step of the phenylpropanoid metabolic pathway, L-phenylalanine (L-Phe) is deaminated to form E-cinnamate, in a conversion catalyzed by phenylalanine ammonia-lyase (PAL; EC 4.3.1.5). The metabolic fate of the ammonium ion (NH4+) produced in this reaction was investigated in sweet potato (Ipomoea batatas) tuber discs. [15N]-Labeled substrates including L-Phe, in the presence or absence of specific enzyme inhibitors, were administered to sweet potato discs in light under aseptic conditions. 15N-Nuclear magnetic resonance spectroscopic analyses revealed that the 15NH4+ liberated during the PAL reaction is first incorporated into the amide nitrogen of L-glutamine (L-Gln) and then into L-glutamate (L-Glu). These results extend our previous observations in pine and potato that PAL-generated NH4+ is assimilated by the glutamine synthetase (GS; EC 6.3.1.2)/glutamate synthase (GOGAT; EC 1.4.1.13) pathway, with the NH4+ so formed ultimately being recycled back to L-Phe via L-Glu as aminoreceptor and donor.
Shi, Haitao; Wang, Xin; Tan, Dun-Xian; Reiter, Russel J; Chan, Zhulong
2015-08-01
The fact of melatonin as an important antioxidant in animals led plant researchers to speculate that melatonin also acts in the similar manner in plants. Although melatonin has significant effects on alleviating stress-triggered reactive oxygen species (ROS), the involvement of melatonin in direct oxidative stress and the underlying physiological and molecular mechanisms remain unclear in plants. In this study, we found that exogenous melatonin significantly alleviated hydrogen peroxide (H2O2)-modulated plant growth, cell damage, and ROS accumulation in Bermuda grass. Additionally, 76 proteins significantly influenced by melatonin during mock or H2O2 treatment were identified by gel-free proteomics using iTRAQ (isobaric tags for relative and absolute quantitation). Metabolic pathway analysis showed that several pathways were markedly enhanced by melatonin and H2O2 treatments, including polyamine metabolism, ribosome pathway, major carbohydrate metabolism, photosynthesis, redox, and amino acid metabolism. Taken together, this study provides more comprehensive insights into the physiological and molecular mechanisms of melatonin in Bermuda grass responses to direct oxidative stress. This may relate to the activation of antioxidants, modulation of metabolic pathways, and extensive proteome reprograming. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Pluripotency and a secretion mechanism of Drosophila transglutaminase.
Shibata, Toshio; Kawabata, Shun-Ichiro
2018-03-01
Transglutaminase (TG) catalyses the formation of an isopeptide bond between glutamine and lysine residues and amine incorporation into specific glutamine residues. TG is conserved in all metazoans and functions both intracellularly and extracellularly. Here we review the existing knowledge of Drosophila TG with an emphasis on its pluripotency: Drosophila TG (i) plays a key role in cuticular morphogenesis, haemolymph coagulation, and entrapment against invading pathogens, (ii) suppresses the immune deficiency pathway to enable immune tolerance against commensal bacteria through the incorporation of polyamines into the nuclear factor-κB-like transcription factor Relish as well as through the protein-protein cross-linking of Relish, (iii) forms a physical matrix in the gut through cross-linking of chitin-binding proteins and (iv) is involved in the maintenance of homeostasis in microbiota in the gut. Moreover, we review the evidence that TG-A, one of alternative splicing-derived isoforms of Drosophila TG, is secreted through an endoplasmic reticulum/Golgi-independent pathway involving exosomes and fatty acylations.
A model for evolution and regulation of nicotine biosynthesis regulon in tobacco.
Kajikawa, Masataka; Sierro, Nicolas; Hashimoto, Takashi; Shoji, Tsubasa
2017-06-03
In tobacco, the defense alkaloid nicotine is produced in roots and accumulates mainly in leaves. Signaling mediated by jasmonates (JAs) induces the formation of nicotine via a series of structural genes that constitute a regulon and are coordinated by JA-responsive transcription factors of the ethylene response factor (ERF) family. Early steps in the pyrrolidine and pyridine biosynthesis pathways likely arose through duplication of the polyamine and nicotinamide adenine dinucleotide (NAD) biosynthetic pathways, respectively, followed by recruitment of duplicated primary metabolic genes into the nicotine biosynthesis regulon. Transcriptional regulation of nicotine biosynthesis by ERF and cooperatively-acting MYC2 transcription factors is implied by the frequency of cognate cis-regulatory elements for these factors in the promoter regions of the downstream structural genes. Indeed, a mutant tobacco with low nicotine content was found to have a large chromosomal deletion in a cluster of closely related ERF genes at the nicotine-controlling NICOTINE2 (NIC2) locus.
An Arginine Deprivation Response Pathway Is Induced in Leishmania during Macrophage Invasion
Strasser, Rona; Zeituni-Molad, Michal; Bendelak, Keren; Rentsch, Doris; Ephros, Moshe; Wiese, Martin; Jardim, Armando; Myler, Peter J.; Zilberstein, Dan
2016-01-01
Amino acid sensing is an intracellular function that supports nutrient homeostasis, largely through controlled release of amino acids from lysosomal pools. The intracellular pathogen Leishmania resides and proliferates within human macrophage phagolysosomes. Here we describe a new pathway in Leishmania that specifically senses the extracellular levels of arginine, an amino acid that is essential for the parasite. During infection, the macrophage arginine pool is depleted due to its use to produce metabolites (NO and polyamines) that constitute part of the host defense response and its suppression, respectively. We found that parasites respond to this shortage of arginine by up-regulating expression and activity of the Leishmania arginine transporter (LdAAP3), as well as several other transporters. Our analysis indicates the parasite monitors arginine levels in the environment rather than the intracellular pools. Phosphoproteomics and genetic analysis indicates that the arginine-deprivation response is mediated through a mitogen-activated protein kinase-2-dependent signaling cascade. PMID:27043018
CO2-induced degradation of amine-containing adsorbents: reaction products and pathways.
Sayari, Abdelhamid; Heydari-Gorji, Aliakbar; Yang, Yong
2012-08-22
A comprehensive study was conducted to investigate the stability of a wide variety of mesoporous silica-supported amine-containing adsorbents in the presence of carbon dioxide under dry conditions. CO(2)-induced degradation of grafted primary and secondary monoamines (pMono, sMono), diamines with one primary and one secondary amines (Diamine) and triamine with one primary and two secondary amines (TRI) as well as different impregnated polyamines such as branched and linear polyethylenimine (BPEI and LPEI) and polyallylamine (PALL) was investigated using extensive CO(2) adsorption-desorption cycling as well as diffuse reflectance infrared Fourier transform (DRIFT) and (13)C CP MAS NMR measurements. Except for sMono, all other supported amines underwent significant deactivation in the presence of dry CO(2) under mild conditions. In all cases, the decrease in CO(2) uptake was associated with the formation of urea linkages at the expense of amine groups. The urea-containing species were identified, and the deactivation pathways were delineated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mishra, Vidhi; Ronning, Donald R.
2012-11-13
The bacterial 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase (MTAN) enzyme is a multifunctional enzyme that catalyzes the hydrolysis of the N-ribosidic bond of at least four different adenosine-based metabolites: S-adenosylhomocysteine (SAH), 5'-methylthioadenosine (MTA), 5'-deoxyadenosine (5'-DOA), and 6-amino-6-deoxyfutalosine. These activities place the enzyme at the hub of seven fundamental bacterial metabolic pathways: S-adenosylmethionine (SAM) utilization, polyamine biosynthesis, the purine salvage pathway, the methionine salvage pathway, the SAM radical pathways, autoinducer-2 biosynthesis, and menaquinone biosynthesis. The last pathway makes MTAN essential for Helicobacter pylori viability. Although structures of various bacterial and plant MTANs have been described, the interactions between the homocysteine moiety of SAH and themore » 5'-alkylthiol binding site of MTAN have never been resolved. We have determined crystal structures of an inactive mutant form of H. pylori MTAN bound to MTA and SAH to 1.63 and 1.20 Å, respectively. The active form of MTAN was also crystallized in the presence of SAH, allowing the determination of the structure of a ternary enzyme–product complex resolved at 1.50 Å. These structures identify interactions between the homocysteine moiety and the 5'-alkylthiol binding site of the enzyme. This information can be leveraged for the development of species-specific MTAN inhibitors that prevent the growth of H. pylori.« less
Tan, Eric C. D.; Snowden-Swan, Lesley J.; Talmadge, Michael; ...
2016-09-27
This paper presents a comparative techno-economic analysis (TEA) of five conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with a specific focus on pathways utilizing oxygenated intermediates. The four emerging pathways of interest are compared with one conventional pathway (Fischer-Tropsch) for the production of the hydrocarbon blendstocks. The processing steps of the four emerging pathways include biomass-to-syngas via indirect gasification, syngas clean-up, conversion of syngas to alcohols/oxygenates followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation. Conversion of biomass-derived syngas to oxygenated intermediates occurs via three different pathways, producing: (i) mixedmore » alcohols over a MoS 2 catalyst, (ii) mixed oxygenates (a mixture of C 2+ oxygenated compounds, predominantly ethanol, acetic acid, acetaldehyde, ethyl acetate) using an Rh-based catalyst, and (iii) ethanol from syngas fermentation. This is followed by the conversion of oxygenates/alcohols to fuel-range olefins in two approaches: (i) mixed alcohols/ethanol to 1-butanol rich mixture via Guerbet reaction, followed by alcohol dehydration, oligomerization, and hydrogenation, and (ii) mixed oxygenates/ethanol to isobutene rich mixture and followed by oligomerization and hydrogenation. The design features a processing capacity of 2000 tonnes/day (2205 short tons) of dry biomass. The minimum fuel selling prices (MFSPs) for the four developing pathways range from 3.40 dollars to 5.04 dollars per gasoline-gallon equivalent (GGE), in 2011 US dollars. Sensitivity studies show that MFSPs can be improved with co-product credits and are comparable to the commercial Fischer-Tropsch benchmark ($3.58/GGE). Altogether, this comparative TEA study documents potential economics for the developmental biofuel pathways via mixed oxygenates.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tan, Eric C. D.; Snowden-Swan, Lesley J.; Talmadge, Michael
This paper presents a comparative techno-economic analysis (TEA) of five conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with a specific focus on pathways utilizing oxygenated intermediates. The four emerging pathways of interest are compared with one conventional pathway (Fischer-Tropsch) for the production of the hydrocarbon blendstocks. The processing steps of the four emerging pathways include biomass-to-syngas via indirect gasification, syngas clean-up, conversion of syngas to alcohols/oxygenates followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation. Conversion of biomass-derived syngas to oxygenated intermediates occurs via three different pathways, producing: (i) mixedmore » alcohols over a MoS 2 catalyst, (ii) mixed oxygenates (a mixture of C 2+ oxygenated compounds, predominantly ethanol, acetic acid, acetaldehyde, ethyl acetate) using an Rh-based catalyst, and (iii) ethanol from syngas fermentation. This is followed by the conversion of oxygenates/alcohols to fuel-range olefins in two approaches: (i) mixed alcohols/ethanol to 1-butanol rich mixture via Guerbet reaction, followed by alcohol dehydration, oligomerization, and hydrogenation, and (ii) mixed oxygenates/ethanol to isobutene rich mixture and followed by oligomerization and hydrogenation. The design features a processing capacity of 2000 tonnes/day (2205 short tons) of dry biomass. The minimum fuel selling prices (MFSPs) for the four developing pathways range from 3.40 dollars to 5.04 dollars per gasoline-gallon equivalent (GGE), in 2011 US dollars. Sensitivity studies show that MFSPs can be improved with co-product credits and are comparable to the commercial Fischer-Tropsch benchmark ($3.58/GGE). Altogether, this comparative TEA study documents potential economics for the developmental biofuel pathways via mixed oxygenates.« less
Thermophotovoltaic in-situ mirror cell
Campbell, Brian C.
1997-01-01
A photovoltaic cell used in a direct energy conversion generator for converting heat to electricity includes a reflective layer disposed within the cell between the active layers of the cell and the cell substrate. The reflective layer reflects photons of low energy back to a photon producing emitter for reabsorption by the emitter, or reflects photons with energy greater than the cell bandgap back to the cell active layers for conversion into electricity. The reflective layer can comprise a reflective metal such as gold while the substrate can comprise heavily doped silicon or a metal.
Conversion of CO2 from Air into Methanol Using a Polyamine and a Homogeneous Ruthenium Catalyst.
Kothandaraman, Jotheeswari; Goeppert, Alain; Czaun, Miklos; Olah, George A; Prakash, G K Surya
2016-01-27
A highly efficient homogeneous catalyst system for the production of CH3OH from CO2 using pentaethylenehexamine and Ru-Macho-BH (1) at 125-165 °C in an ethereal solvent has been developed (initial turnover frequency = 70 h(-1) at 145 °C). Ease of separation of CH3OH is demonstrated by simple distillation from the reaction mixture. The robustness of the catalytic system was shown by recycling the catalyst over five runs without significant loss of activity (turnover number > 2000). Various sources of CO2 can be used for this reaction including air, despite its low CO2 concentration (400 ppm). For the first time, we have demonstrated that CO2 captured from air can be directly converted to CH3OH in 79% yield using a homogeneous catalytic system.
Correlations between polyamine ratios and growth patterns in seedling roots
NASA Technical Reports Server (NTRS)
Shen, H. J.; Galston, A. W.
1985-01-01
The levels of putrescine, cadaverine, spermidine and spermine were determined in seedling roots of pea, tomato, millet and corn, as well as in corn coleoptiles and pea internodes. In all roots, putrescine content increased as elongation progressed, and the putrescine/spermine ratio closely paralleled the sigmoid growth curve up until the time of lateral root initiation. Spermidine and spermine were most abundant near the apices and declined progressively with increasing age of the cells. In the zone of differentiation of root hairs in pea roots, putrescine rose progressively with increasing age, while cadaverine declined. In both pea internodes and corn coleoptiles, the putrescine/spermidine ratio rises with increasing age and elongation. Thus, a block in the conversion of the diamine putrescine to the triamine spermidine may be an important step in the change from cell division to cell elongation.
Demonstrating Energy Conversion with Piezoelectric Crystals and a Paddle Fan
ERIC Educational Resources Information Center
Rakbamrung, Prissana; Putson, Chatchai; Muensit, Nantakan
2014-01-01
A simple energy conversion system--particularly, the conversion of mechanical energy into electrical energy by using shaker flashlights--has recently been presented. This system uses hand generators, consisting of a magnet in a tube with a coil wrapped around it, and acts as an ac source when the magnet passes back and forth through the coil.…
Biological Conversion of Sugars to Hydrocarbons Technology Pathway
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, Ryan; Biddy, Mary J.; Tan, Eric
2013-03-31
In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This technology pathway case investigates the biological conversion of biomass derivedmore » sugars to hydrocarbon biofuels, utilizing data from recent literature references and information consistent with recent pilot scale demonstrations at NREL. Technical barriers and key research needs have been identified that should be pursued for the pathway to become competitive with petroleum-derived gasoline, diesel and jet range hydrocarbon blendstocks.« less
Heterologous expression and characterization of mouse spermine oxidase.
Cervelli, Manuela; Polticelli, Fabio; Federico, Rodolfo; Mariottini, Paolo
2003-02-14
Polyamine oxidases are key enzymes responsible of the polyamine interconversion metabolism in animal cells. Recently, a novel enzyme belonging to this class of enzymes has been characterized for its capability to oxidize preferentially spermine and designated as spermine oxidase. This is a flavin adenine dinucleotide-containing enzyme, and it has been expressed both in vitro and in vivo systems. The primary structure of mouse spermine oxidase (mSMO) was deduced from a cDNA clone (Image Clone 264769) recovered by a data base search utilizing the human counterpart of polyamine oxidases, PAOh1. The open reading frame predicts a 555-amino acid protein with a calculated M(r) of 61,852.30, which shows a 95.1% identity with PAOh1. To understand the biochemical properties of mSMO and its structure/function relationship, the mSMO cDNA has been subcloned and expressed in secreted and secreted-tagged forms into Escherichia coli BL21 DE3 cells. The recombinant enzyme shows an optimal pH value of 8.0 and is able to oxidize rapidly spermine to spermidine and 3-aminopropanal and fails to act upon spermidine and N(1)-acetylpolyamines. The purified recombinant-tagged form enzyme (M(r) approximately 68,000) has K(m) and k(cat) values of 90 microm and 4.5 s(-1), respectively, using spermine as substrate at pH 8.0. Molecular modeling of mSMO protein based on maize polyamine oxidase three-dimensional structure suggests that the general features of maize polyamine oxidase active site are conserved in mSMO.
Yordanova, Martina M; Wu, Cheng; Andreev, Dmitry E; Sachs, Matthew S; Atkins, John F
2015-07-17
The protein antizyme is a negative regulator of cellular polyamine concentrations from yeast to mammals. Synthesis of functional antizyme requires programmed +1 ribosomal frameshifting at the 3' end of the first of two partially overlapping ORFs. The frameshift is the sensor and effector in an autoregulatory circuit. Except for Saccharomyces cerevisiae antizyme mRNA, the frameshift site alone only supports low levels of frameshifting. The high levels usually observed depend on the presence of cis-acting stimulatory elements located 5' and 3' of the frameshift site. Antizyme genes from different evolutionary branches have evolved different stimulatory elements. Prior and new multiple alignments of fungal antizyme mRNA sequences from the Agaricomycetes class of Basidiomycota show a distinct pattern of conservation 5' of the frameshift site consistent with a function at the amino acid level. As shown here when tested in Schizosaccharomyces pombe and mammalian HEK293T cells, the 5' part of this conserved sequence acts at the nascent peptide level to stimulate the frameshifting, without involving stalling detectable by toe-printing. However, the peptide is only part of the signal. The 3' part of the stimulator functions largely independently and acts at least mostly at the nucleotide level. When polyamine levels were varied, the stimulatory effect was seen to be especially responsive in the endogenous polyamine concentration range, and this effect may be more general. A conserved RNA secondary structure 3' of the frameshift site has weaker stimulatory and polyamine sensitizing effects on frameshifting. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
Filippova, Ekaterina V.; Kuhn, Misty L.; Osipiuk, Jerzy; Kiryukhina, Olga; Joachimiak, Andrzej; Ballicora, Miguel A.
2015-01-01
Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence of a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase (GNAT) superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key towards understanding the regulation of polyamine levels in bacteria during pathogenesis. PMID:25623305
Independent roles of eIF5A and polyamines in cell proliferation
2004-01-01
To examine the roles of active hypusinated eIF5A (eukaryotic translation initiation factor 5A) and polyamines in cell proliferation, mouse mammary carcinoma FM3A cells were treated with an inhibitor of deoxyhypusine synthase, GC7 (N1-guanyl-1, 7-diaminoheptane), or with an inhibitor of ornithine decarboxylase, DFMO (α-difluoromethylornithine), or with DFMO plus an inhibitor of spermine synthase, APCHA [N1-(3-aminopropyl)-cyclohexylamine]. Treatment with GC7 decreased the level of active eIF5A on day 1 without affecting cellular polyamine content, and inhibition of cell growth occurred from day 2. This delay reflects the fact that eIF5A was present in excess and was very stable in these cells. Treatment with DFMO or with DFMO plus APCHA inhibited cell growth on day 1. DFMO considerably decreased the levels of putrescine and spermidine, and the formation of active eIF5A began to decrease when the level of spermidine fell below 8 nmol/mg of protein after 12 h of incubation with DFMO. The combination of DFMO and APCHA markedly decreased the levels of putrescine and spermine and significantly decreased the level of spermidine, but did not affect the level of active eIF5A until day 3 when spermidine level decreased to 7 nmol/mg of protein. The results show that a decrease in either active eIF5A or polyamines inhibits cell growth, indicating that eIF5A and polyamines are independently involved in cell growth. PMID:15377278
Polyamines and ethylene interact in rice grains in response to soil drying during grain filling.
Chen, Tingting; Xu, Yunji; Wang, Jingchao; Wang, Zhiqin; Yang, Jianchang; Zhang, Jianhua
2013-05-01
This study tested the hypothesis that the interaction between polyamines and ethylene may mediate the effects of soil drying on grain filling of rice (Oryza sativa L.). Two rice cultivars were pot grown. Three treatments, well-watered, moderate soil drying (MD), and severe soil drying (SD), were imposed from 8 d post-anthesis until maturity. The endosperm cell division rate, grain-filling rate, and grain weight of earlier flowering superior spikelets showed no significant differences among the three treatments. However, those of the later flowering inferior spikelets were significantly increased under MD and significantly reduced under SD when compared with those which were well watered. The two cultivars showed the same tendencies. MD increased the contents of free spermidine (Spd) and free spermine (Spm), the activities of S-adenosyl-L-methionine decarboxylase and Spd synthase, and expression levels of polyamine synthesis genes, and decreased the ethylene evolution rate, the contents of 1-aminocylopropane-1-carboxylic acid (ACC) and hydrogen peroxide, the activities of ACC synthase, ACC oxidase, and polyamine oxidase, and the expression levels of ethylene synthesis genes in inferior spikelets. SD exhibited the opposite effects. Application of Spd, Spm, or an inhibitor of ethylene synthesis to rice panicles significantly reduced ethylene and ACC levels, but significantly increased Spd and Spm contents, grain-filling rate, and grain weight of inferior spikelets. The results were reversed when ACC or an inhibitor of Spd and Spm synthesis was applied. The results suggest that a potential metabolic interaction between polyamines and ethylene biosynthesis responds to soil drying and mediates the grain filling of inferior spikelets in rice.
Fillingame, R H; Jorstad, C M; Morris, D R
1975-01-01
There are large increases in cellular levels of the polyamines spermidine and spermine in lymphocytes induced to transform by concanavalin A. The anti-leukemic agent methylglyoxal bis(guanylhydrazone) (MGBG) blocks synthesis of these polyamines by inhibiting S-adenosylmethionine decarboxylase. Previous results showed that when cells are activated in the presence of MGBG the synthesis and processing of RNA, as well as protein synthesis, proceed as in the absence of the drug. In contrast, the incorporation of [methyl-3H]thymidine into DNA and the rate of entry of the cells into mitosis are inhibited by 60% in the presence of MGBG. Several experiments suggest that MGBG inhibits cell proliferation by directly blocking polyamine synthesis and not by an unrelated pharmacological effect: (1) the inhibitory action of MGBG is reversed by exogenously added spermidine or spermine; (2) inhibition of DNA synthesis by MGBG shows the same dose-response curve as does inhibition of spermidine and spermine synthesis; and (3) if MGBG is added to cells which have been allowed to accumulate their maximum complement of polyamines, there is no inhibition of thymidine incorporation. MGBG-treated and control cultures initiate DNA synthesis at the same time and show the same percentage of labeled cells by autoradiography. Therefore, it appears that in the absence of increased cellular levels of polyamines, lymphocytes progress normally from G0 through G1 and into S-phase. Furthermore, these experiments suggest that the increased levels of spermidine and spermine generally seen in rapidly proliferating eukaryotic systems are necessary for enhanced rates of DNA replication. PMID:1060087
USDA-ARS?s Scientific Manuscript database
The study was conducted to investigate the optimal hormone treatment for rooting in bitter melon and the effect of defoliation on rooting and polyamine levels. Commercial preparation (diluted 1:10 and 1: 20) gave extensive rooting within five days after treatment. The presence of leaf with the stem ...
S.C. Minocha; R. Minocha; A. Komamine
1991-01-01
Changes in the activites of S-adcnosylmethionine (SAM) synthetase (methionine adenosyltransferase, EC 2.5.1.6.) and SAM decarboxylase (EC 4.1.1.50) were studied in carrot (Daucus carota) cell cultures in response to 2,4-dichlorophenoxyacetic acid (2,4-D) and several inhibitors of polyamine biosynthesis. Activity of SAM synthetase increased...
High-performance liquid chromatographic method for the determination of dansyl-polyamines
Subhash C. Minocha; Rakesh Minocha; Cheryl A. Robie
1990-01-01
This paper describes a fast reliable, and a sensitive technique for the separation and quantification of dansylated polyamines by high-performance liquid chromatography. Using a small 33 x 4.6 mm I.D., 3 ?m particle size, C18 reversed-phase cartridge column and a linear gradient of acetonitrile-heptanesulfonate (10 mM, pH 3.4...
Rakesh Minocha; Subhash C. Minocha; Stephanie Long
2004-01-01
The major objective of this study was to determine if the observed changes in polyamines and their biosynthetic enzymes during somatic embryo development were specifically related to either the stage of the embryo development or to the duration of time spent on the maturation medium. Somatic embryos of red spruce (Picea rubens) at different...
Subhash C. Minocha; Cheryl A. Robie; Akhtar J. Khan; Nancy S. Papa; Andrew I. Samuelsen; Rakesh Minocha
1990-01-01
Carrot cell cultures provide a model experimental system for the analysis of biochemical and molecular events associated with morphogenesis in plants (3, 4, 5, 14). Among the biochemical changes accompanying somatic embryogenesis in this tissue is an increased biosynthesis ofpolyamines (1, 2, 7, 10, 11, 13). A variety of inhibitors of polyamine biosynthetic enzymes...
Gong, Xiaoqing; Shi, Shuting; Dou, Fangfang; Song, Yi; Ma, Fengwang
2017-09-13
Since melatonin was identified in plants decades ago, much attention has been devoted to discovering its role in plant science. There is still a great deal to learn about the functional importance of melatonin, as well as its functional mode. In this paper, we examine the role of melatonin treatment in the response of Malus hupehensis Rehd. to alkaline conditions. Stressed seedlings showed chlorosis and suppressed growth. However, this phenotype was ameliorated when 5 µM melatonin was added to the irrigation solution. This supplementation was also associated with a reduction in cell membrane damage and maintenance of a normal root system architecture. Fewer reactive oxygen species (ROS) were accumulated due to the enhanced scavenging activity of antioxidant enzymes superoxide dismutase, peroxidase, and catalase. In addition, alkaline-stressed seedlings that received the melatonin supplement accumulated more polyamines compared with untreated seedlings. Transcript levels of six genes involved in polyamine synthesis, including SAMDC1 , - 3 , and - 4 , and SPDS1 , - 3 , and - 5 , - 6 , were upregulated in response to melatonin application. All of these results demonstrate that melatonin has a positive function in plant tolerance to alkaline stress because it regulates enzyme activity and the biosynthesis of polyamines.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dermody, D.L.; Peez, R.F.; Bergbreiter, D.E.
1999-02-02
The authors report a new molecular-filter approach for enhancing the selectivity of chemical sensors. Specifically, they describe electrochemical sensors prepared from Au electrodes coated with {beta}-cyclodextrin-functionalized, hyperbranched poly(acrylic acid)(PAA) films capped with a chemically grafted, ultrathin polyamine layer. The hyperbranched PAA film is a highly functionalized framework for covalently binding the {beta}-cyclodextrin molecular receptors. The thin, grafted polyamine overlayer acts as a pH-sensitive molecular filter that selectively passes suitably charged analytes. Poly(amidoamine) dendrimers or poly-D-lysine is used as 10--15-nm-thick filter layers. The results show that at low pH, when the polyamines are fully protonated, positively charged redox probe molecules, suchmore » as benzyl viologen (BV), do not permeate the filter layer. However, at high pH, when the filter layer is uncharged, BV penetrates the filter layer and is reduced at the electrode. The opposite pH dependence is observed for negatively charged redox molecules such as anthraquinone-2-sulfonate (AQS). Both BV and AQS specifically interact with the {beta}-cyclodextrin receptors underlying the polyamine filter layers.« less
Role of Spermidine in Overwintering of Cyanobacteria
Zhu, Xiangzhi; Li, Qiong; Yin, Chuntao; Fang, Xiantao
2015-01-01
ABSTRACT Polyamines are found in all groups of cyanobacteria, but their role in environmental adaptation has been barely investigated. In Synechocystis sp. strain PCC 6803, inactivation of spermidine synthesis genes significantly reduced the survivability under chill (5°C)-light stress, and the survivability could be restored by addition of spermidine. To analyze the effects of spermidine on gene expression at 5°C, lacZ was expressed from the promoter of carboxy(nor)spermidine decarboxylase gene (CASDC) in Synechocystis. Synechocystis 6803::PCASDC-lacZ pretreated at 15°C showed a high level of LacZ activity for a long period of time at 5°C; without the pretreatment or with protein synthesis inhibited at 5°C, the enzyme activity gradually decreased. In a spermidine-minus mutant harboring PCASDC-lacZ, lacZ showed an expression pattern as if protein synthesis were inhibited at 5°C, even though the stability of its mRNA increased. Four other genes, including rpoA that encodes the α subunit of RNA polymerase, showed similar expression patterns. The chill-light stress led to a rapid increase of protein carbonylation in Synechocystis. The protein carbonylation then quickly returned to the background level in the wild type but continued to slowly increase in the spermidine-minus mutant. Our results indicate that spermidine promotes gene expression and replacement of damaged proteins in cyanobacteria under the chill-light stress in winter. IMPORTANCE Outbreak of cyanobacterial blooms in freshwater lakes is a worldwide environmental problem. In the annual cycle of bloom-forming cyanobacteria, overwintering is the least understood stage. Survival of Synechocystis sp. strain PCC 6803 under long-term chill (5°C)-light stress has been established as a model for molecular studies on overwintering of cyanobacteria. Here, we show that spermidine, the most common polyamine in cyanobacteria, promotes the survivability of Synechocystis under long-term chill-light stress and that the physiological function is based on its effects on gene expression and recovery from protein damage. This is the first report on the role of polyamines in survival of overwintering cyanobacteria. We also analyzed spermidine synthesis pathways in cyanobacteria on the basis of bioinformatic and experimental data. PMID:25917915
Biological Conversion of Sugars to Hydrocarbons Technology Pathway
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, R.; Biddy, M.; Tan, E.
2013-03-01
This technology pathway case investigates the biological conversion of biomass-derived sugars to hydrocarbon biofuels, utilizing data from recent literature references and information consistent with recent pilot-scale demonstrations at NREL. Technical barriers and key research needs have been identified that should be pursued for the pathway to become competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks.
Phytomonas: transport of amino acids, hexoses and polyamines.
Canepa, Gaspar E; Carrillo, Carolina; Armesto, Arnaldo R; Bouvier, León A; Miranda, Mariana R; Pereira, Claudio A
2007-09-01
Phytomonas cells (Phytomonas Jma) isolated from the latex of Jatropha macrantha were assayed for amino acid, hexose and polyamine transport. Results showed high transport rates for glucose and fructose (193 and 128 pmol min(-1) 10(-7) cells, respectively) and lower, but significant rates, for proline, arginine, cysteine and glutamate (between 1.7 and 5.8 pmol min(-1) 10(-7) cells). Minor transport activities were observed for serine, glycine and aspartate (<1 pmol min(-1) 10(-7) cells). Amino acid transport processes do not seem to be regulated by starvation or during the growth phases. Polyamine transport was also evaluated showing a clear preference for spermidine over putrescine (3.4 and 0.4 pmol min(-1) 10(-7) cells, respectively). This work represents the first report on metabolite transport in phytomonads.
Nakov, Natalija; Bogdanovska, Liljana; Acevska, Jelena; Tonic-Ribarska, Jasmina; Petkovska, Rumenka; Dimitrovska, Aneta; Kasabova, Lilia; Svinarov, Dobrin
2016-11-01
In this research, as a part of the development of fast and reliable HPLC-MS/MS method for quantification of ibuprofen (IBP) enantiomers in human plasma, the possibility of IBP acylglucoronide (IBP-Glu) back-conversion was assessed. This involved investigation of in source and in vitro back-conversion. The separation of IBP enantiomers, its metabolite and rac-IBP-d3 (internal standard), was achieved within 6 min using Chiracel OJ-RH chromatographic column (150 × 2.1 mm, 5 μm). The followed selected reaction monitoring transitions for IBP-Glu (m/z 381.4 → 205.4, m/z 381.4 → 161.4 and m/z 205.4 → 161.4) implied that under the optimized electrospray ionization parameters, in source back-conversion of IBP-Glu was insignificant. The results obtained after liquid-liquid extraction of plasma samples spiked with IBP-Glu revealed that the amount of IBP enantiomers generated by IBP-Glu back-conversion was far <20% of lower limit of quantification sample. These results indicate that the presence of IBP-Glu in real samples will not affect the quantification of the IBP enantiomers; thereby reliability of the method was improved. Additional advantage of the method is the short analysis time making it suitable for the large number of samples. The method was fully validated according to the EMA guideline and was shown to meet all requirements to be applied in a pharmacokinetic study. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Molecular evolution of the polyamine oxidase gene family in Metazoa
2012-01-01
Background Polyamine oxidase enzymes catalyze the oxidation of polyamines and acetylpolyamines. Since polyamines are basic regulators of cell growth and proliferation, their homeostasis is crucial for cell life. Members of the polyamine oxidase gene family have been identified in a wide variety of animals, including vertebrates, arthropodes, nematodes, placozoa, as well as in plants and fungi. Polyamine oxidases (PAOs) from yeast can oxidize spermine, N1-acetylspermine, and N1-acetylspermidine, however, in vertebrates two different enzymes, namely spermine oxidase (SMO) and acetylpolyamine oxidase (APAO), specifically catalyze the oxidation of spermine, and N1-acetylspermine/N1-acetylspermidine, respectively. Little is known about the molecular evolutionary history of these enzymes. However, since the yeast PAO is able to catalyze the oxidation of both acetylated and non acetylated polyamines, and in vertebrates these functions are addressed by two specialized polyamine oxidase subfamilies (APAO and SMO), it can be hypothesized an ancestral reference for the former enzyme from which the latter would have been derived. Results We analysed 36 SMO, 26 APAO, and 14 PAO homologue protein sequences from 54 taxa including various vertebrates and invertebrates. The analysis of the full-length sequences and the principal domains of vertebrate and invertebrate PAOs yielded consensus primary protein sequences for vertebrate SMOs and APAOs, and invertebrate PAOs. This analysis, coupled to molecular modeling techniques, also unveiled sequence regions that confer specific structural and functional properties, including substrate specificity, by the different PAO subfamilies. Molecular phylogenetic trees revealed a basal position of all the invertebrates PAO enzymes relative to vertebrate SMOs and APAOs. PAOs from insects constitute a monophyletic clade. Two PAO variants sampled in the amphioxus are basal to the dichotomy between two well supported monophyletic clades including, respectively, all the SMOs and APAOs from vertebrates. The two vertebrate monophyletic clades clustered strictly mirroring the organismal phylogeny of fishes, amphibians, reptiles, birds, and mammals. Evidences from comparative genomic analysis, structural evolution and functional divergence in a phylogenetic framework across Metazoa suggested an evolutionary scenario where the ancestor PAO coding sequence, present in invertebrates as an orthologous gene, has been duplicated in the vertebrate branch to originate the paralogous SMO and APAO genes. A further genome evolution event concerns the SMO gene of placental, but not marsupial and monotremate, mammals which increased its functional variation following an alternative splicing (AS) mechanism. Conclusions In this study the explicit integration in a phylogenomic framework of phylogenetic tree construction, structure prediction, and biochemical function data/prediction, allowed inferring the molecular evolutionary history of the PAO gene family and to disambiguate paralogous genes related by duplication event (SMO and APAO) and orthologous genes related by speciation events (PAOs, SMOs/APAOs). Further, while in vertebrates experimental data corroborate SMO and APAO molecular function predictions, in invertebrates the finding of a supported phylogenetic clusters of insect PAOs and the co-occurrence of two PAO variants in the amphioxus urgently claim the need for future structure-function studies. PMID:22716069
Molecular evolution of the polyamine oxidase gene family in Metazoa.
Polticelli, Fabio; Salvi, Daniele; Mariottini, Paolo; Amendola, Roberto; Cervelli, Manuela
2012-06-20
Polyamine oxidase enzymes catalyze the oxidation of polyamines and acetylpolyamines. Since polyamines are basic regulators of cell growth and proliferation, their homeostasis is crucial for cell life. Members of the polyamine oxidase gene family have been identified in a wide variety of animals, including vertebrates, arthropodes, nematodes, placozoa, as well as in plants and fungi. Polyamine oxidases (PAOs) from yeast can oxidize spermine, N1-acetylspermine, and N1-acetylspermidine, however, in vertebrates two different enzymes, namely spermine oxidase (SMO) and acetylpolyamine oxidase (APAO), specifically catalyze the oxidation of spermine, and N1-acetylspermine/N1-acetylspermidine, respectively. Little is known about the molecular evolutionary history of these enzymes. However, since the yeast PAO is able to catalyze the oxidation of both acetylated and non acetylated polyamines, and in vertebrates these functions are addressed by two specialized polyamine oxidase subfamilies (APAO and SMO), it can be hypothesized an ancestral reference for the former enzyme from which the latter would have been derived. We analysed 36 SMO, 26 APAO, and 14 PAO homologue protein sequences from 54 taxa including various vertebrates and invertebrates. The analysis of the full-length sequences and the principal domains of vertebrate and invertebrate PAOs yielded consensus primary protein sequences for vertebrate SMOs and APAOs, and invertebrate PAOs. This analysis, coupled to molecular modeling techniques, also unveiled sequence regions that confer specific structural and functional properties, including substrate specificity, by the different PAO subfamilies. Molecular phylogenetic trees revealed a basal position of all the invertebrates PAO enzymes relative to vertebrate SMOs and APAOs. PAOs from insects constitute a monophyletic clade. Two PAO variants sampled in the amphioxus are basal to the dichotomy between two well supported monophyletic clades including, respectively, all the SMOs and APAOs from vertebrates. The two vertebrate monophyletic clades clustered strictly mirroring the organismal phylogeny of fishes, amphibians, reptiles, birds, and mammals. Evidences from comparative genomic analysis, structural evolution and functional divergence in a phylogenetic framework across Metazoa suggested an evolutionary scenario where the ancestor PAO coding sequence, present in invertebrates as an orthologous gene, has been duplicated in the vertebrate branch to originate the paralogous SMO and APAO genes. A further genome evolution event concerns the SMO gene of placental, but not marsupial and monotremate, mammals which increased its functional variation following an alternative splicing (AS) mechanism. In this study the explicit integration in a phylogenomic framework of phylogenetic tree construction, structure prediction, and biochemical function data/prediction, allowed inferring the molecular evolutionary history of the PAO gene family and to disambiguate paralogous genes related by duplication event (SMO and APAO) and orthologous genes related by speciation events (PAOs, SMOs/APAOs). Further, while in vertebrates experimental data corroborate SMO and APAO molecular function predictions, in invertebrates the finding of a supported phylogenetic clusters of insect PAOs and the co-occurrence of two PAO variants in the amphioxus urgently claim the need for future structure-function studies.
Borole, Abhijeet P.
2015-08-25
Conversion of biomass into bioenergy is possible via multiple pathways resulting in production of biofuels, bioproducts and biopower. Efficient and sustainable conversion of biomass, however, requires consideration of many environmental and societal parameters in order to minimize negative impacts. Integration of multiple conversion technologies and inclusion of upcoming alternatives such as bioelectrochemical systems can minimize these impacts and improve conservation of resources such as hydrogen, water and nutrients via recycle and reuse. This report outlines alternate pathways integrating microbial electrolysis in biorefinery schemes to improve energy efficiency while evaluating environmental sustainability parameters.
Vilas-Boas, V; Silva, R; Guedes-de-Pinho, P; Carvalho, F; Bastos, M L; Remião, F
2014-09-01
Paraquat (PQ) is a widely used, highly toxic and non-selective contact herbicide, which has been associated with central neurotoxic effects, namely the development of Parkinson's disease, but whose effects to the blood-brain barrier (BBB) itself have rarely been studied. This work studied the mechanisms of PQ uptake and efflux in a rat's BBB cell model, the RBE4 cells. PQ is believed to enter cells using the basic or neutral amino acid or polyamine transport systems or through the choline-uptake system. In contrast, PQ efflux from cells is reported to be mediated by P-glycoprotein. Therefore, we evaluated PQ-induced cytotoxicity and the effect of some substrates/blockers of these transporters (such as arginine, L-valine, putrescine, hemicholinium-3 and GF120918) on such cytotoxicity. RBE4 cells were shown to be extremely resistant to PQ after 24 h of exposure; even at concentrations as high as 50 mM approximately 45% of the cells remained viable. Prolonging exposure until 48 h elicited significant cytotoxicity only for PQ concentrations above 5 mM. Although hemicholinium-3, a choline-uptake system inhibitor, significantly protected cells against PQ-induced toxicity, none of the effects were observed for arginine, L-valine or putrescine. Meanwhile, inhibiting the efflux pump P-glycoprotein using GF120918 significantly enhanced PQ-induced cytotoxicity. In conclusion, PQ used the choline-uptake system, instead of the transporters for the basic or neutral amino acids or for the polyamines, to enter RBE4 cells. P-glycoprotein extrudes PQ back to the extracellular medium. However, this efflux mechanism only partially explains the observed RBE4 resistance to PQ. Copyright © 2013 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Chee, Kuan W. A.; Hu, Yuning
2018-07-01
There has always been an inexorable interest in the solar industry in boosting the photovoltaic conversion efficiency. This paper presents a theoretical and numerical simulation study of the effects of key design parameters on the photoelectric performance of single junction (InGaP- or GaAs-based) and dual junction (InGaP/GaAs) inorganic solar cells. The influence of base layer thickness, base doping concentration, junction temperature, back surface field layer composition and thickness, and tunnel junction material, were correlated with open circuit voltage, short-circuit current, fill factor and power conversion efficiency performance. The InGaP/GaAs dual junction solar cell was optimized with the tunnel junction and back surface field designs, yielding a short-circuit current density of 20.71 mAcm-2 , open-circuit voltage of 2.44 V and fill factor of 88.6%, and guaranteeing an optimal power conversion efficiency of at least 32.4% under 1 sun AM0 illumination even without an anti-reflective coating.
Pledgie-Tracy, Allison; Billam, Madhavi; Hacker, Amy; Sobolewski, Michele D; Woster, Patrick M.; Zhang, Zhe; Casero, Robert A.; Davidson, Nancy E
2009-01-01
Polyamine analogues have demonstrated significant activity against human breast cancer cell lines as single agents as well as in combination with other cytotoxic drugs. This study evaluates the ability of a polyamine analogue N1, N11-bis(ethyl)norspermine (BENSpm) to synergize with six standard chemotherapeutic agents, 5-fluorouracil (FU), fluorodeoxyuridine, cis- diaminechloroplatinum(II) (DDP), paclitaxel, docetaxel, and vinorelbine, in four human breast cancer cell lines and one immortalized, non-tumorigenic mammary epithelial cell line. BENSpm exhibited synergistic inhibitory effect on cell proliferation in combination with 5-FU or paclitaxel in human breast cancer cell lines (MDA-MB-231 and MCF-7) and either antagonistic or less effective in the non-tumorigenic MCF-10A cell line. Synergism was highest with 120 hour concomitant treatment or pre-treatment with BENSpm for 24 hours followed by concomitant treatment for 96 additional hours. Since the cytotoxic effects of many polyamine analogues and cytotoxic agents are believed to act, in part, through induction of the polyamine catabolic enzymes SSAT and SMO, the role of these enzymes on synergistic response was evaluated in MDA-MB-231- and MCF-7-treated with BENSpm and 5-FU or paclitaxel. Combination treatments of BENSpm with 5-FU or paclitaxel resulted in induction of SSAT mRNA and activity in both cell lines compared to either drug alone, while SMO mRNA and activity were increased only in MDA-MB-231 cells. Induction was greater with BENSpm/paclitaxel combination than BENSpm/5-FU. Further, RNAi studies demonstrated that both SSAT and SMO play a significant role in the response of MDA-MB-231 cells to treatment with BENSpm and 5-FU or paclitaxel. In MCF-7 cells, only SSAT appears to be involved in the response to these treatments. In an effort to translate combination studies from in vitro to in vivo, and to form a basis for clinical setting, the in vivo therapeutic efficacy of BENSpm alone and in combination with paclitaxel on tumor regression was evaluated in xenograft mice models generated with MDA-MB-231 cells. Intraperitoneal exposure to BENSpm or taxol singly and in combination for 4 weeks resulted in significant inhibition in tumor growth These findings help elucidate the mechanisms involved in synergistic drug response and support combinations of polyamine analogues with chemotherapeutic agents which could potentially be used in the treatment of breast cancer. PMID:19727732
Li, Jianming; Hu, Lipan; Zhang, Li; Pan, Xiongbo; Hu, Xiaohui
2015-12-29
Salinity-alkalinity stress is known to adversely affect a variety of processes in plants, thus inhibiting growth and decreasing crop yield. Polyamines protect plants against a variety of environmental stresses. However, whether exogenous spermidine increases the tolerance of tomato seedlings via effects on chloroplast antioxidant enzymes and chlorophyll metabolism is unknown. In this study, we examined the effect of exogenous spermidine on chlorophyll synthesis and degradation pathway intermediates and related enzyme activities, as well as chloroplast ultrastructure, gene expression, and antioxidants in salinity-alkalinity-stressed tomato seedlings. Salinity-alkalinity stress disrupted chlorophyll metabolism and hindered uroorphyrinogen III conversion to protoporphyrin IX. These effects were more pronounced in seedlings of cultivar Zhongza No. 9 than cultivar Jinpengchaoguan. Under salinity-alkalinity stress, exogenous spermidine alleviated decreases in the contents of total chlorophyll and chlorophyll a and b in seedlings of both cultivars following 4 days of stress. With extended stress, exogenous spermidine reduced the accumulation of δ-aminolevulinic acid, porphobilinogen, and uroorphyrinogen III and increased the levels of protoporphyrin IX, Mg-protoporphyrin IX, and protochlorophyllide, suggesting that spermidine promotes the conversion of uroorphyrinogen III to protoporphyrin IX. The effect occurred earlier in cultivar Jinpengchaoguan than in cultivar Zhongza No. 9. Exogenous spermidine also alleviated the stress-induced increases in malondialdehyde content, superoxide radical generation rate, chlorophyllase activity, and expression of the chlorophyllase gene and the stress-induced decreases in the activities of antioxidant enzymes, antioxidants, and expression of the porphobilinogen deaminase gene. In addition, exogenous spermidine stabilized the chloroplast ultrastructure in stressed tomato seedlings. The tomato cultivars examined exhibited different capacities for responding to salinity-alkalinity stress. Exogenous spermidine triggers effective protection against damage induced by salinity-alkalinity stress in tomato seedlings, probably by maintaining chloroplast structural integrity and alleviating salinity-alkalinity-induced oxidative damage, most likely through regulation of chlorophyll metabolism and the enzymatic and non-enzymatic antioxidant systems in chloroplast. Exogenous spermidine also exerts positive effects at the transcription level, such as down-regulation of the expression of the chlorophyllase gene and up-regulation of the expression of the porphobilinogen deaminase gene.
Xinhua Zhou; Rakesh Minocha; Subhash C. Minocha
1995-01-01
The effects of aluminum (Al) treatment on polyamines were studied using suspension cultures of Madagascar periwinkle [Catharanthus roseus (L.) G. Don]. The addition of A1 (0.2, 0.5, 1.0 mM) to the suspension cultures caused a significant increase in putrescine within 24h only in freshly transferred cells. By contrast, Al treatment reduced putrescine...
Autar K. Mattoo; Subhash C. Minocha; Rakesh Minocha; Avtar K. Handa
2010-01-01
Distribution of biogenic amines--the diamine putrescine (Put), triamine spermidine (Spd), and tetraamine spermine (Spm)--differs between species with Put and Spd being particularly abundant and Spm the least abundant in plant cells. These amines are important for cell viability and their intracellular levels are tightly regulated, which have made it difficult to...
Ornithine: at the crossroads of multiple paths to amino acids and polyamines
Rajtilak Majumdar; Rakesh Minocha; Subhash Minocha
2015-01-01
After the 20 amino acids that make up the proteins in all living organisms, ornithine perhaps occupies the most critical position among the non-protein amino acids. It sits at the crossroads of interconversions of glutamate and arginine on the one hand and the production of proline, polyamines and several alkaloids on the other: all products of tremendous importance to...
The regulation of autophagy differentially affects Trypanosoma cruzi metacyclogenesis.
Vanrell, María Cristina; Losinno, Antonella Denisse; Cueto, Juan Agustín; Balcazar, Darío; Fraccaroli, Laura Virginia; Carrillo, Carolina; Romano, Patricia Silvia
2017-11-01
Autophagy is a cellular process required for the removal of aged organelles and cytosolic components through lysosomal degradation. All types of eukaryotic cells from yeasts to mammalian cells have the machinery to activate autophagy as a result of many physiological and pathological situations. The most frequent stimulus of autophagy is starvation and the result, in this case, is the fast generation of utilizable food (e.g. amino acids and basic nutrients) to maintain the vital biological processes. In some organisms, starvation also triggers other associated processes such as differentiation. The protozoan parasite Trypanosoma cruzi undergoes a series of differentiation processes throughout its complex life cycle. Although not all autophagic genes have been identified in the T. cruzi genome, previous works have demonstrated the presence of essential autophagic-related proteins. Under starvation conditions, TcAtg8, which is the parasite homolog of Atg8/LC3 in other organisms, is located in autophagosome-like vesicles. In this work, we have characterized the autophagic pathway during T. cruzi differentiation from the epimastigote to metacyclic trypomastigote form, a process called metacyclogenesis. We demonstrated that autophagy is stimulated during metacyclogenesis and that the induction of autophagy promotes this process. Moreover, with exception of bafilomycin, other classical autophagy modulators have similar effects on T. cruzi autophagy. We also showed that spermidine and related polyamines can positively regulate parasite autophagy and differentiation. We concluded that both polyamine metabolism and autophagy are key processes during T. cruzi metacyclogenesis that could be exploited as drug targets to avoid the parasite cycle progression.
Characterization of arginine decarboxylase from Dianthus caryophyllus.
Ha, Byung Hak; Cho, Ki Joon; Choi, Yu Jin; Park, Ky Young; Kim, Kyung Hyun
2004-04-01
Arginine decarboxylase (ADC, EC 4.1.1.9) is a key enzyme in the biosynthesis of polyamines in higher plants, whereas ornithine decarboxylase represents the sole pathway of polyamine biosynthesis in animals. Previously, we characterized a genomic clone from Dianthus caryophyllus, in which the deduced polypeptide of ADC was 725 amino acids with a molecular mass of 78 kDa. In the present study, the ADC gene was subcloned into the pGEX4T1 expression vector in combination with glutathione S-transferase (GST). The fusion protein GST-ADC was water-soluble and thus was purified by sequential GSTrap-arginine affinity chromatography. A thrombin-mediated on-column cleavage reaction was employed to release free ADC from GST. Hiload superdex gel filtration FPLC was then used to obtain a highly purified ADC. The identity of the ADC was confirmed by immunoblot analysis, and its specific activity with respect to (14)C-arginine decarboxylation reaction was determined to be 0.9 CO(2) pkat mg(-1) protein. K(m) and V(max) of the reaction between ADC and the substrate were 0.077 +/- 0.001 mM and 6.0 +/- 0.6 pkat mg(-1) protein, respectively. ADC activity was reduced by 70% in the presence of 0.1 mM Cu(2+) or CO(2+), but was only marginally affected by Mg(2+), or Ca(2+) at the same concentration. Moreover, spermine at 1 mM significantly reduced its activity by 30%.
Liu, Taibo; Huang, Binbin; Chen, Lin; Xian, Zhiqiang; Song, Shiwei; Chen, Riyuan; Hao, Yanwei
2018-06-30
Polyamines (PAs), including putrescine (Put), spermidine (Spd), spermine (Spm), and thermospermine (T-Spm), play key roles in plant development, including fruit setting and ripening, morphogenesis, and abiotic/biotic stress. Their functions appear to be intimately related to their synthesis, which occurs via arginine/ornithine decarboxylase (ADC/ODC), Spd synthase (SPDS), Spm synthase (SPMS), and Acaulis5 (ACL5), respectively. Unfortunately, the expression and function of these PA synthesis-relate genes during specific developmental process or under stress have not been fully elucidated. Here, we present the results of a genome-wide analysis of the PA synthesis genes (ADC, ODC, SPDS, SPMS, ACL5) in the tomato (Solanum lycopersicum). In total, 14 PA synthesis-related genes were identified. Further analysis of their structures, conserved domains, phylogenetic trees, predicted subcellular localization, and promoter cis-regulatory elements were analyzed. Furthermore, we also performed experiments to evaluate their tissue expression patterns and under hormone and various stress treatments. To our knowledge, this is the first study to elucidate the mechanisms underlying PA function in this variety of tomato. Taken together, these data provide valuable information for future functional characterization of specific genes in the PA synthesis pathway in this and other plant species. Although additional research is required, the insight gained by this and similar studies can be used to improve our understanding of PA metabolism ultimately leading to more effective and consistent plant cultivation. Copyright © 2018 Elsevier B.V. All rights reserved.
Interactive Behaviors in Adolescent Conversation Dyads.
ERIC Educational Resources Information Center
Turkstra, Lyn; Ciccia, Angela; Seaton, Christine
2003-01-01
This study collected normative behavioral data from extemporaneous 3-minute conversations of 50 typically developing adolescents. Analysis found the following high frequency behaviors: directing gaze at the partner, nodding and showing neutral and positive facial expressions, using back-channel responses, and giving contingent responses.…
NASA Astrophysics Data System (ADS)
Tomasi, Andrea; Paviet-Salomon, Bertrand; Jeangros, Quentin; Haschke, Jan; Christmann, Gabriel; Barraud, Loris; Descoeudres, Antoine; Seif, Johannes Peter; Nicolay, Sylvain; Despeisse, Matthieu; de Wolf, Stefaan; Ballif, Christophe
2017-04-01
For crystalline-silicon solar cells, voltages close to the theoretical limit are nowadays readily achievable when using passivating contacts. Conversely, maximal current generation requires the integration of the electron and hole contacts at the back of the solar cell to liberate its front from any shadowing loss. Recently, the world-record efficiency for crystalline-silicon single-junction solar cells was achieved by merging these two approaches in a single device; however, the complexity of fabricating this class of devices raises concerns about their commercial potential. Here we show a contacting method that substantially simplifies the architecture and fabrication of back-contacted silicon solar cells. We exploit the surface-dependent growth of silicon thin films, deposited by plasma processes, to eliminate the patterning of one of the doped carrier-collecting layers. Then, using only one alignment step for electrode definition, we fabricate a proof-of-concept 9-cm2 tunnel-interdigitated back-contact solar cell with a certified conversion efficiency >22.5%.
Harry-O'kuru, Rogers E; Biresaw, Girma; Murray, Rex E
2015-07-22
Renewable resources have evoked a new awakening in both scientific and industrial circles in the past decade. Vegetable oil is one category of renewables that is amenable as a source of new industrial products. Because the source feedstock, seeds, are environmentally friendly, the derivatized products from these at the end of their lifetime could also be benign when designed appropriately. Bioethanol and biodiesel are examples of biobased industrial products currently in the market place and have become resources for uplifting the rural economy. Biolubricants also are playing a more prominent role because they have become closely competitive with petroleum-based lubricants. These products are renewable because the crops from which the feedstuff for the biofuels and biolubricants are produced are grown annually in contrast to nonrenewable mineral sources. Added to their renewability is the inherent biodegradability of their end-use products after their useful lifetime. In a recent study of the lubricity characteristics of peracylated polyhydroxy milkweed oil, the derivatives were found to exhibit good oxidative stability as well as excellent antiwear properties. To further explore an expansion in the properties of such materials in lubrication and other applications, in this study the polyhydroxy (OH) moieties of derivatized milkweed triglycerides were replaced with -NHR groupings in the oil. In this process novel polyketo triglyceride intermediates leading to polyamine derivatives of the vegetable oil have been synthesized. The polyamine triglyceride markedly improved the stability of the parent oil to oxidative stress. It has also attenuated the extreme viscosity of the starting polyhydroxy oil to a more useful product that could be amenable for use as a lubricating agent, for example, hydraulic fluid. Both the polyketone and polyimine intermediates of the polyamine have chelating properties. The intermediates and the polyamine were characterized spectroscopically, tribologically, and rheologically for their intrinsic properties.
Controlling of N-alkylpolyamine analogue metabolism by selective deuteration.
Ucal, Sebahat; Häkkinen, Merja R; Alanne, Aino-Liisa; Alhonen, Leena; Vepsäläinen, Jouko; Keinänen, Tuomo A; Hyvönen, Mervi T
2018-02-14
Replacing protium with deuterium is an efficient method to modulate drug metabolism. N -alkylated polyamine analogues are polyamine antimetabolites with proven anticancer efficacy. We have characterized earlier the preferred metabolic routes of N 1 , N 12 -diethylspermine (DESpm), N 1 -benzyl- N 12 -ethylspermine (BnEtSpm) and N 1 , N 12 -dibenzylspermine (DBSpm) by human recombinant spermine oxidase (SMOX) and acetylpolyamine oxidase (APAO). Here, we studied the above analogues, their variably deuterated counterparts and their metabolites as substrates and inhibitors of APAO, SMOX, semicarbazide-sensitive amine oxidase (SSAO), diamine oxidase (DAO) and monoamine oxidases. We found that targeted deuteration efficiently redirected the preferable cleavage site and suppressed reaction rate by APAO and SMOX in vitro We found a three- to six-fold decline in V max with moderate variable effect on K m when deuterium was located at the preferred hydrogen abstraction site of the analogue. We also found some of the metabolites to be potent inhibitors of DAO and SSAO. Surprisingly, analogue deuteration did not markedly alter the anti-proliferative efficacy of the drugs in DU145 prostate cancer cells, while in mouse embryonic fibroblasts, which had higher basal APAO and SMOX activities, moderate effect was observed. Interestingly, the anti-proliferative efficacy of the analogues did not correlate with their ability to suppress polyamine biosynthetic enzymes, induce spermidine/spermine- N 1 -acetyltransferase or deplete intracellular polyamine levels, but correlated with their ability to induce SMOX. Our data show that selective deuteration of N -alkyl polyamine analogues enables metabolic switching, offering the means for selective generation of bioactive metabolites inhibiting, e.g. SSAO and DAO, thus setting a novel basis for in vivo studies of this class of analogues. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.
Filippova, Ekaterina V.; Kuhn, Misty L.; Osipiuk, Jerzy; ...
2015-01-23
Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence ofmore » a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key toward understanding the regulation of polyamine levels in bacteria during pathogenesis.« less
Barret, Jean-Marc; Kruczynski, Anna; Vispé, Stéphane; Annereau, Jean-Philippe; Brel, Viviane; Guminski, Yves; Delcros, Jean-Guy; Lansiaux, Amélie; Guilbaud, Nicolas; Imbert, Thierry; Bailly, Christian
2008-12-01
The polyamine transport system (PTS) is an energy-dependent machinery frequently overactivated in cancer cells with a high demand for polyamines. We have exploited the PTS to selectively deliver a polyamine-containing drug to cancer cells. F14512 combines an epipodophyllotoxin core-targeting topoisomerase II with a spermine moiety introduced as a cell delivery vector. The polyamine tail supports three complementary functions: (a) facilitate formulation of a water-soluble compound, (b) increase DNA binding to reinforce topoisomerase II inhibition, and (c) facilitate selective uptake by tumor cells via the PTS. F14512 is 73-fold more cytotoxic to Chinese hamster ovary cells compared with CHO-MG cells with a reduced PTS activity. A decreased sensitivity of L1210 leukemia cells to F14512 was observed in the presence of putrescine, spermidine, and spermine. In parallel, the spermine moiety considerably enhances the drug-DNA interaction, leading to a reinforced inhibition of topoisomerase II. The spermine tail of F14512 serves as a cell delivery vehicle as well as a DNA anchor, and this property translates at the cellular level into a distinct pharmacologic profile. Twenty-nine human solid or hematologic cell lines were used to characterize the high cytotoxic potential of F14512 (median IC50 of 0.18 micromol/L). Finally, the potent antitumor activity of F14512 in vivo was evidenced with a MX1 human breast tumor xenograft model, with partial and complete tumor regressions. This work supports the clinical development of F14512 as a novel targeted cytotoxic drug and sheds light on the concept of selective delivery of drugs to tumor cells expressing the PTS.
Fu, Xing-Zheng; Chen, Chuan-Wu; Wang, Yin; Liu, Ji-Hong; Moriguchi, Takaya
2011-03-28
Enormous work has shown that polyamines are involved in a variety of physiological processes, but information is scarce on the potential of modifying disease response through genetic transformation of a polyamine biosynthetic gene. In the present work, an apple spermidine synthase gene (MdSPDS1) was introduced into sweet orange (Citrus sinensis Osbeck 'Anliucheng') via Agrobacterium-mediated transformation of embryogenic calluses. Two transgenic lines (TG4 and TG9) varied in the transgene expression and cellular endogenous polyamine contents. Pinprick inoculation demonstrated that the transgenic lines were less susceptible to Xanthomonas axonopodis pv. citri (Xac), the causal agent of citrus canker, than the wild type plants (WT). In addition, our data showed that upon Xac attack TG9 had significantly higher free spermine (Spm) and polyamine oxidase (PAO) activity when compared with the WT, concurrent with an apparent hypersensitive response and the accumulation of more H₂O₂. Pretreatment of TG9 leaves with guazatine acetate, an inhibitor of PAO, repressed PAO activity and reduced H₂O₂ accumulation, leading to more conspicuous disease symptoms than the controls when both were challenged with Xac. Moreover, mRNA levels of most of the defense-related genes involved in synthesis of pathogenesis-related protein and jasmonic acid were upregulated in TG9 than in the WT regardless of Xac infection. Our results demonstrated that overexpression of the MdSPDS1 gene prominently lowered the sensitivity of the transgenic plants to canker. This may be, at least partially, correlated with the generation of more H₂O₂ due to increased production of polyamines and enhanced PAO-mediated catabolism, triggering hypersensitive response or activation of defense-related genes.
2011-01-01
Background Enormous work has shown that polyamines are involved in a variety of physiological processes, but information is scarce on the potential of modifying disease response through genetic transformation of a polyamine biosynthetic gene. Results In the present work, an apple spermidine synthase gene (MdSPDS1) was introduced into sweet orange (Citrus sinensis Osbeck 'Anliucheng') via Agrobacterium-mediated transformation of embryogenic calluses. Two transgenic lines (TG4 and TG9) varied in the transgene expression and cellular endogenous polyamine contents. Pinprick inoculation demonstrated that the transgenic lines were less susceptible to Xanthomonas axonopodis pv. citri (Xac), the causal agent of citrus canker, than the wild type plants (WT). In addition, our data showed that upon Xac attack TG9 had significantly higher free spermine (Spm) and polyamine oxidase (PAO) activity when compared with the WT, concurrent with an apparent hypersensitive response and the accumulation of more H2O2. Pretreatment of TG9 leaves with guazatine acetate, an inhibitor of PAO, repressed PAO activity and reduced H2O2 accumulation, leading to more conspicuous disease symptoms than the controls when both were challenged with Xac. Moreover, mRNA levels of most of the defense-related genes involved in synthesis of pathogenesis-related protein and jasmonic acid were upregulated in TG9 than in the WT regardless of Xac infection. Conclusion Our results demonstrated that overexpression of the MdSPDS1 gene prominently lowered the sensitivity of the transgenic plants to canker. This may be, at least partially, correlated with the generation of more H2O2 due to increased production of polyamines and enhanced PAO-mediated catabolism, triggering hypersensitive response or activation of defense-related genes. PMID:21439092
Wu, Jianqiang; Shu, Sheng; Li, Chengcheng; Sun, Jin; Guo, Shirong
2018-07-01
Hydrogen peroxide (H 2 O 2 ) is a key signaling molecule that mediates a variety of physiological processes and defense responses against abiotic stress in higher plants. In this study, our aims are to clarify the role of H 2 O 2 accumulation induced by the exogenous application of spermidine (Spd) to cucumber (Cucumis sativus) seedlings in regulating the antioxidant capacity of roots under salt stress. The results showed that Spd caused a significant increase in endogenous polyamines and H 2 O 2 levels, and peaked at 2 h after salt stress. Spd-induced H 2 O 2 accumulation was blocked under salt stress by pretreatment with a H 2 O 2 scavenger and respective inhibitors of cell wall peroxidase (CWPOD; EC: 1.11.1.7), polyamine oxidase (PAO; EC: 1.5.3.11) and NADPH oxidase (NOX; EC: 1.6.3.1); among these three inhibitors, the largest decrease was found in response to the addition of the inhibitor of polyamine oxidase. In addition, we observed that exogenous Spd could increase the activities of the enzymes superoxide dismutase (SOD; EC: 1.15.1.1), peroxidase (POD; EC: 1.11.1.7) and catalase (CAT; EC: 1.11.1.6) as well as the expression of their genes in salt-stressed roots, and the effects were inhibited by H 2 O 2 scavengers and polyamine oxidase inhibitors. These results suggested that, by regulating endogenous PAs-mediated H 2 O 2 signaling in roots, Spd could enhance antioxidant enzyme activities and reduce oxidative damage; the main source of H 2 O 2 was polyamine oxidation, which was associated with improved tolerance and root growth recovery of cucumber under salt stress. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
NASA Astrophysics Data System (ADS)
Alberca, Lucas N.; Sbaraglini, María L.; Balcazar, Darío; Fraccaroli, Laura; Carrillo, Carolina; Medeiros, Andrea; Benitez, Diego; Comini, Marcelo; Talevi, Alan
2016-04-01
Chagas disease is a parasitic infection caused by the protozoa Trypanosoma cruzi that affects about 6 million people in Latin America. Despite its sanitary importance, there are currently only two drugs available for treatment: benznidazole and nifurtimox, both exhibiting serious adverse effects and limited efficacy in the chronic stage of the disease. Polyamines are ubiquitous to all living organisms where they participate in multiple basic functions such as biosynthesis of nucleic acids and proteins, proliferation and cell differentiation. T. cruzi is auxotroph for polyamines, which are taken up from the extracellular medium by efficient transporters and, to a large extent, incorporated into trypanothione (bis-glutathionylspermidine), the major redox cosubstrate of trypanosomatids. From a 268-compound database containing polyamine analogs with and without inhibitory effect on T. cruzi we have inferred classificatory models that were later applied in a virtual screening campaign to identify anti-trypanosomal compounds among drugs already used for other therapeutic indications (i.e. computer-guided drug repositioning) compiled in the DrugBank and Sweetlead databases. Five of the candidates identified with this strategy were evaluated in cellular models from different pathogenic trypanosomatids ( T. cruzi wt, T. cruzi PAT12, T. brucei and Leishmania infantum), and in vitro models of aminoacid/polyamine transport assays and trypanothione synthetase inhibition assay. Triclabendazole, sertaconazole and paroxetine displayed inhibitory effects on the proliferation of T. cruzi (epimastigotes) and the uptake of putrescine by the parasite. They also interfered with the uptake of others aminoacids and the proliferation of infective T. brucei and L. infantum (promastigotes). Trypanothione synthetase was ruled out as molecular target for the anti-parasitic activity of these compounds.
Filippova, Ekaterina V; Kuhn, Misty L; Osipiuk, Jerzy; Kiryukhina, Olga; Joachimiak, Andrzej; Ballicora, Miguel A; Anderson, Wayne F
2015-03-27
Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence of a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key toward understanding the regulation of polyamine levels in bacteria during pathogenesis. Copyright © 2015. Published by Elsevier Ltd.
Evaluation and comparison of biochemical markers of anthropogenic stress in the sheepshead minnow
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stuck, K.; Furst, H.; Boyd, C.
1995-12-31
The utility of bioenergetic and growth-rate indices for assessing chemically induced stress in larval and juvenile sheepshead minnows (Cyprinodon variegatus) was investigated. Viable embryos were exposed to zinc chloride at concentrations of 0.6, 1.5 and 3.8 ppm over a period of 28 days. Samples were collected from each exposure group and a unexposed control group on days 7, 14 and 28 of the study. Individual fish were measured and weighed wet. Triacylglycerol (TAG) and sterol content of exposed and control fish was determined using a FID/TLC latroscan system, polyamines were quantified by HPLC, nucleic acids levels were determined using anmore » ethidium bromide fluorescence technique, and % tissue solids were estimated by dry weight analysis. A significant reduction in the TAG:sterol ratio was observed among fish exposed to 3.8 ppm ZnCl for 28 days. TAG:sterol was significantly correlated with growth-rate, % tissue solids, and concentration of ZnCl. RNA:DNA and polyamine (putrescine: spermine) ratios were significantly higher among day 7 control and exposed fish than those obtained from fish collected on days 14 and 28. RNA:DNA ratios of fish exposed to 3.8 ppm ZnCl for 28 days were significantly lower than those of fish in the control group. Polyamine ratios from fish exposed to 3.8 ppm ZnCl were significantly lower than control fish after 14 days of exposure. There was a significant correlation between polyamine ratios and concentration of ZnCl. TAG:sterol, RNA:DNA, and polyamine ratios can be used to biochemically assess anthropogenic stress; however, due to ontogenetic changes, these indicators are applicable only after endogenous yolk reserves have been depleted.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Filippova, Ekaterina V.; Kuhn, Misty L.; Osipiuk, Jerzy
Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence ofmore » a previously unknown allosteric site and an unusual dodecameric structure for a member of the Gcn5-related N-acetyltransferase superfamily. We show that SpeG forms dodecamers in solution and in crystals and describe its three-dimensional structure in several ligand-free and liganded structures. Importantly, these structural data define the first view of a polyamine bound in an allosteric site of an N-acetyltransferase. Kinetic characterization of SpeG from V. cholerae showed that it acetylates spermidine and spermine. The behavior of this enzyme is complex and exhibits sigmoidal curves and substrate inhibition. We performed a detailed non-linear regression kinetic analysis to simultaneously fit families of substrate saturation curves to uncover a simple kinetic mechanism that explains the apparent complexity of this enzyme. Our results provide a fundamental understanding of the bacterial SpeG enzyme, which will be key toward understanding the regulation of polyamine levels in bacteria during pathogenesis.« less
Defining the role of polyamines in colon carcinogenesis using mouse models
Ignatenko, Natalia A.; Gerner, Eugene W.; Besselsen, David G.
2011-01-01
Genetics and diet are both considered important risk determinants for colorectal cancer, a leading cause of death in the US and worldwide. Genetically engineered mouse (GEM) models have made a significant contribution to the characterization of colorectal cancer risk factors. Reliable, reproducible, and clinically relevant animal models help in the identification of the molecular events associated with disease progression and in the development of effictive treatment strategies. This review is focused on the use of mouse models for studying the role of polyamines in colon carcinogenesis. We describe how the available mouse models of colon cancer such as the multiple intestinal neoplasia (Min) mice and knockout genetic models facilitate understanding of the role of polyamines in colon carcinogenesis and help in the development of a rational strategy for colon cancer chemoprevention. PMID:21712957
Ramon, Mathew; Geuns, Jan M C; Swennen, Rony; Pannis, Bart
2002-01-01
Polyamines and fatty acids were studied in proliferating meristem cultures of 3 banana cultivars with high (Cachaco), medium (Williams Bronze free) and low (Mbwazirume) survival rates after cryopreservation. A 2-week preculture on medium containing 0.4 M sucrose which is essential to obtain survival after cryopreservation resulted in increased polyamine levels, especially putrescine. This increase in putrescine content was positively correlated with the survival rate after simple freezing or after vitrification. The total fatty acid content also increased after a 0.4 M sucrose pretreatment. However, only the ratio of unsaturated/saturated fatty acids correlated positively with the survival rate after cryopreservation. This is the first report showing a correlation of both putrescine increase and level of unsaturation of membrane lipids after sucrose treatment with survival rate after cryopreservation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tan, Eric C. D.; Snowden-Swan, Lesley J.; Talmadge, Michael
This paper presents a comparative techno-economic analysis (TEA) of five conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with specific focus on pathways utilizing oxygenated intermediates. The four emerging pathways of interest are compared with one conventional pathway (Fischer-Tropsch) for the production of the hydrocarbon blendstocks. The processing steps of the four emerging pathways include: biomass to syngas via indirect gasification, gas cleanup, conversion of syngas to alcohols/oxygenates followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation. Conversion of biomass-derived syngas to oxygenated intermediates occurs via three different pathways, producing: 1)more » mixed alcohols over a MoS2 catalyst, 2) mixed oxygenates (a mixture of C2+ oxygenated compounds, predominantly ethanol, acetic acid, acetaldehyde, ethyl acetate) using an Rh-based catalyst, and 3) ethanol from syngas fermentation. This is followed by the conversion of oxygenates/alcohols to fuel-range olefins in two approaches: 1) mixed alcohols/ethanol to 1-butanol rich mixture via Guerbet reaction, followed by alcohol dehydration, oligomerization, and hydrogenation, and 2) mixed oxygenates/ethanol to isobutene rich mixture and followed by oligomerization and hydrogenation. The design features a processing capacity of 2,000 tonnes/day (2,205 short tons) of dry biomass. The minimum fuel selling prices (MFSPs) for the four developing pathways range from $3.40 to $5.04 per gasoline-gallon equivalent (GGE), in 2011 US dollars. Sensitivity studies show that MFSPs can be improved with co-product credits and are comparable to the commercial Fischer-Tropsch benchmark ($3.58/GGE). Overall, this comparative TEA study documents potential economics for the developmental biofuel pathways via mixed oxygenates.« less
A concise entry into nonsymmetrical alkyl polyamines.
Pirali, Tracey; Callipari, Grazia; Ercolano, Emanuela; Genazzani, Armando A; Giovenzana, Giovanni Battista; Tron, Gian Cesare
2008-10-02
The synthesis of nonsymmetrical polyamines (PAs) has, up to now, been problematic due to lengthy synthetic procedures, lack of regioselectivity, and very poor atom economy. An innovative synthetic protocol for nonsymmetrical PAs using a modified Ugi reaction ( N-split Ugi) which simplifies the synthesis of these tricky compounds is described. We believe that this new synthesis may open the door for the generation of new and pharmacologically active PAs.
Tabor, Herbert; Tabor, Celia White; Cohn, Murray S.; Hafner, Edmund W.
1981-01-01
The presence of certain rpsL (strA) mutations in a strain of Escherichia coli that cannot synthesize putrescine or spermidine because of deletions in ornithine decarboxylase, arginine decarboxylase, and agmatine ureohydrolase, converts a partial requirement for polyamines for growth into an absolute requirement. PMID:7021537
Effect of polyamines on mechanical and structural properties of Bombyx mori silk.
Yerra, Aparna; Mysarla, Danti Kumari; Siripurapu, Prasanthi; Jha, Anjali; Valluri, Satyavathi V; Mamillapalli, Anitha
2017-01-01
Silkworm, Bombyx mori (B. mori) belongs to the Lepidoptera family. The silk produced from this insect, mulberry silk, gained lot of importance as a fabric. Silk is being exploited as a biomaterial due to its surprising strength and biocompatibility. Polyamines (PA) are important cell growth regulators. In the present work the effect of treatment of polyamines, putrescine (Put), spermidine (Spd), and spermine (Spm) on the quantity and quality of silk produced was assessed. Results showed that exogenous feeding of Spd at a concentration of 50 µM increased fiber length significantly. Analysis by Fourier transform infrared (FTIR) on the properties of silk obtained from Spd treated silkworms revealed an increase in percentage of absorption with no difference in peak positions of amide I and amide III groups. Scanning electron microscopy (SEM) revealed an increase in diameter of silk. Further, analysis at molecular level showed an increase in fibroin expression in Spd treated silk glands. However, the Spd treatment showed no significant difference with respect to fibroin to sericin ratio per unit weight of cocoon, silk tenacity, and percent elongation. Thus, the present results show that polyamine treatment would influence silk quality at structural, mechanical, and molecular level in the Bombyx mori, which can be exploited in silk biomaterial production. © 2016 Wiley Periodicals, Inc.
Teh, Huey Fang; Neoh, Bee Keat; Wong, Yick Ching; Kwong, Qi Bin; Ooi, Tony Eng Keong; Ng, Theresa Lee Mei; Tiong, Soon Huat; Low, Jaime Yoke Sum; Danial, Asma Dazni; Ersad, Mohd Amiron; Kulaveerasingam, Harikrishna; Appleton, David R
2014-08-13
Oil palm is one of the most productive oil-producing crops and can store up to 90% oil in its fruit mesocarp. Oil palm fruit is a sessile drupe consisting of a fleshy mesocarp from which palm oil is extracted. Biochemical changes in the mesocarp cell walls, polyamines, and hormones at different ripening stages of oil palm fruits were studied, and the relationship between the structural and the biochemical metabolism of oil palm fruits during ripening is discussed. Time-course analysis of the changes in expression of polyamines, hormones, and cell-wall-related genes and metabolites provided insights into the complex processes and interactions involved in fruit development. Overall, a strong reduction in auxin-responsive gene expression was observed from 18 to 22 weeks after pollination. High polyamine concentrations coincided with fruit enlargement during lipid accumulation and latter stages of maturation. The trend of abscisic acid (ABA) concentration was concordant with GA₄ but opposite to the GA₃ profile such that as ABA levels increase the resulting elevated ABA/GA₃ ratio clearly coincides with maturation. Polygalacturonase, expansin, and actin gene expressions were also observed to increase during fruit maturation. The identification of the master regulators of these coordinated processes may allow screening for oil palm variants with altered ripening profiles.
Breeding Perspectives and Programs at East Lansing
USDA-ARS?s Scientific Manuscript database
USDA-ARS sugar beet breeding activities for both Aphanomyces resistance and CMS/O-type conversion at East Lansing reach back to the 1940’s, with variety testing activities at Michigan State University reaching back to circa 1911. Many of those contributions are well known in the sugar beet breeding ...
Deciphering drought-induced metabolic responses and regulation in developing maize kernels.
Yang, Liming; Fountain, Jake C; Ji, Pingsheng; Ni, Xinzhi; Chen, Sixue; Lee, Robert D; Kemerait, Robert C; Guo, Baozhu
2018-02-12
Drought stress conditions decrease maize growth and yield, and aggravate preharvest aflatoxin contamination. While several studies have been performed on mature kernels responding to drought stress, the metabolic profiles of developing kernels are not as well characterized, particularly in germplasm with contrasting resistance to both drought and mycotoxin contamination. Here, following screening for drought tolerance, a drought-sensitive line, B73, and a drought-tolerant line, Lo964, were selected and stressed beginning at 14 days after pollination. Developing kernels were sampled 7 and 14 days after drought induction (DAI) from both stressed and irrigated plants. Comparative biochemical and metabolomic analyses profiled 409 differentially accumulated metabolites. Multivariate statistics and pathway analyses showed that drought stress induced an accumulation of simple sugars and polyunsaturated fatty acids and a decrease in amines, polyamines and dipeptides in B73. Conversely, sphingolipid, sterol, phenylpropanoid and dipeptide metabolites accumulated in Lo964 under drought stress. Drought stress also resulted in the greater accumulation of reactive oxygen species (ROS) and aflatoxin in kernels of B73 in comparison with Lo964 implying a correlation in their production. Overall, field drought treatments disordered a cascade of normal metabolic programming during development of maize kernels and subsequently caused oxidative stress. The glutathione and urea cycles along with the metabolism of carbohydrates and lipids for osmoprotection, membrane maintenance and antioxidant protection were central among the drought stress responses observed in developing kernels. These results also provide novel targets to enhance host drought tolerance and disease resistance through the use of biotechnologies such as transgenics and genome editing. © 2018 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Fukuwatari, Tsutomu; Toriochi, Mai; Ohta, Mari; Sasaki, Ryuzo; Shibata, Katsumi
2004-02-01
Bisphenol A, a monomer of polycarbonate plastics, disturbed the conversion pathway of the amino acid tryptophan to the vitamin nicotinamide. The conversion ratio of tryptophan to nicotinamide was reduced to 1/15 by feeding a diet containing 1% bisphenol A. A putative disturbing reaction is kynurenine-->3-hydroxykynurenine, which is catalyzed by kynurenine monohydroxylase. This is an FAD-enzyme and requires NADPH as a coenzyme. Styrene monomer (1% addition to a normal diet) did not affect the food intake or the body weight, but slightly reduced the conversion ratio of tryptophan-nicotinamide.
Rakesh Minocha; Walter C. Shortle; Daniel J. Jr. Coughin; Subhash C. Minocha
1996-01-01
The influence of age of red spruce (Picea rubens Sarg.) cell suspensions on aluminum (Al) effects was studied by adding AICI3 (0.2, 0.5, and 1.0 mM) to the media on each day of a 7-day culture period and analyzing for changes in total cell mass, polyamines, arginine decarboxylase activity, and inorganic ions after 24 h of...
Rakesh Minocha; Subhash C. Minocha; Stephanie L. Long; Walter C. Shortle
1992-01-01
Increased aluminum (Al) solubility in soil waters due to acid precipitation has aroused considerable interest in the problem of Al toxicity in plants. In the present study, an in vitro suspension culture system of Catharanthus roseus (L.) G. Don was used to analyze the effects of aluminum on several biochemical processes in these cells. The aliphatic...
Rakesh Minocha; Stephanie Long
2004-01-01
The objective of the present study was to develop a rapid HPLC method for simultaneous separation and quantitation of dansylated amino acids and common polyamines in the same matrix for analyzing forest tree tissues and cell cultures. The major modifications incorporated into this method as compared to previously published HPLC methods for separation of only dansyl...
Chou, Leo Y T; Song, Fayi; Chan, Warren C W
2016-04-06
DNA assembly of nanoparticles is a powerful approach to control their properties and prototype new materials. However, the structure and properties of DNA-assembled nanoparticles are labile and sensitive to interactions with counterions, which vary with processing and application environment. Here we show that substituting polyamines in place of elemental counterions significantly enhanced the structural rigidity and plasmonic properties of DNA-assembled metal nanoparticles. These effects arose from the ability of polyamines to condense DNA and cross-link DNA-coated nanoparticles. We further used polyamine wrapped DNA nanostructures as structural templates to seed the growth of polymer multilayers via layer-by-layer assembly, and controlled the degree of DNA condensation, plasmon coupling efficiency, and material responsiveness to environmental stimuli by varying polyelectrolyte composition. These results highlight counterion engineering as a versatile strategy to tailor the properties of DNA-nanoparticle assemblies for various applications, and should be applicable to other classes of DNA nanostructures.
Characterization of a Polyamine Microsphere and Its Adsorption for Protein
Wang, Feng; Liu, Pei; Nie, Tingting; Wei, Huixian; Cui, Zhenggang
2013-01-01
A novel polyamine microsphere, prepared from the water-in-oil emulsion of polyethylenimine, was characterized. The investigation of scanning electron microscopy showed that the polyamine microsphere is a regular ball with a smooth surface. The diameter distribution of the microsphere is 0.37–4.29 μm. The isoelectric point of the microsphere is 10.6. The microsphere can adsorb proteins through the co-effect of electrostatic and hydrophobic interactions. Among the proteins tested, the highest value of adsorption of microsphere, 127.8 mg·g−1 microsphere, was obtained with lipase. In comparison with other proteins, the hydrophobic force is more important in promoting the adsorption of lipase. The microsphere can preferentially adsorb lipase from an even mixture of proteins. The optimum temperature and pH for the selective adsorption of lipase by the microsphere was 35 °C and pH 7.0. PMID:23344018
Analysis of the reflective multibandgap solar cell concept
NASA Technical Reports Server (NTRS)
Stern, T. G.
1983-01-01
A new and unique approach to improving photovoltaic conversion efficiency, the reflective multiband gap solar cell concept, was examined. This concept uses back surface reflectors and light trapping with several physically separated cells of different bandgaps to make more effective use of energy from different portions of the solar spectrum. Preliminary tests performed under General Dynamics Independent Research and Development (IRAD) funding have demonstrated the capability for achieving in excess of 20% conversion efficiency with aluminum gallium arsenide and silicon. This study analyzed the ultimate potential for high conversion efficiency with 2, 3, 4, and 5 different bandgap materials, determined the appropriate bandgaps needed to achieve this optimized efficiency, and identified potential problems or constraints. The analysis indicated that an improvement in efficiency of better than 40% could be attained in this multibandgap approach, compared to a single bandgap converter under the same assumptions. Increased absorption loss on the back surface reflector was found to incur a minimal penalty on efficiency for two and three bandgap systems. Current models for bulk absorption losses in 3-5 materials were found to be inadequate for explaining laboratory observed transmission losses. Recommendations included the continued development of high bandgap back surface reflector cells and basic research on semiconductor absorption mechanisms.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weese, R K; Burnham, A K
Dimensional changes related to temperature cycling of the {beta} and {delta} polymorphs of HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) are important for a variety of applications. The coefficient of thermal expansion (CTE) of the {beta} and {delta} phases are measured over a temperature range of -20 C to 215 C by thermo-mechanical analysis (TMA). Dimensional changes associated with the phase transition were also measured, and the time-temperature dependence of the dimensional change is consistent with phase transition kinetics measured earlier by differential scanning calorimetry (DSC). One HMX sample measured by TMA during its initial heating and again three days later during a second heatingmore » showed the {beta}-to-{delta} phase transition a second time, thereby indicating back conversion from {delta}-to-{beta} phase HMX during those three days. DSC was used to measure kinetics of the {delta}-to-{beta} back conversion. The most successful approach was to first heat the material to create the {delta} phase, then after a given period at room temperature, measure the heat absorbed during a second pass through the {beta}-to-{delta} phase transition. Back conversion at room temperature follows nucleation-growth kinetics.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weese, R K; Burnham, A K; Maienschein, J L
Dimensional changes related to temperature cycling of the beta and delta polymorphs of HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) are important for a variety of applications. The coefficient of thermal expansion (CTE) of the beta and delta phases are measured and reported in this work over a temperature range of -20 C to 215 C. In addition, dimensional changes associated with the phase transition were measured, both through the transition and back down. Initially, differential scanning calorimetry (DSC) was used to investigate back conversion of the delta phase to the beta phase polymorph. The most successful approach was first to measure the amount ofmore » the beta to delta conversion, then after a given cooling period a repeat analysis, to measure the heat consumed by a second pass through the beta to delta phase transition. In addition, TMA is used to measure the dimensional change of a 0.20-gram sample of HMX during its initial heating and then three days later during a 2nd heating. This HMX shows the beta to delta phase transition a second time, thereby confirming the back conversion from delta to beta phase HMX.« less
Analysis of Triplet Exciton Loss Pathways in PTB7:PC71BM Bulk Heterojunction Solar Cells
NASA Astrophysics Data System (ADS)
Kraus, Hannes; Heiber, Michael C.; Väth, Stefan; Kern, Julia; Deibel, Carsten; Sperlich, Andreas; Dyakonov, Vladimir
2016-07-01
A strategy for increasing the conversion efficiency of organic photovoltaics has been to increase the VOC by tuning the energy levels of donor and acceptor components. However, this opens up a new loss pathway from an interfacial charge transfer state to a triplet exciton (TE) state called electron back transfer (EBT), which is detrimental to device performance. To test this hypothesis, we study triplet formation in the high performing PTB7:PC71BM blend system and determine the impact of the morphology-optimizing additive 1,8-diiodoctane (DIO). Using photoluminescence and spin-sensitive optically detected magnetic resonance (ODMR) measurements at low temperature, we find that TEs form on PC71BM via intersystem crossing from singlet excitons and on PTB7 via EBT mechanism. For DIO blends with smaller fullerene domains, an increased density of PTB7 TEs is observed. The EBT process is found to be significant only at very low temperature. At 300 K, no triplets are detected via ODMR, and electrically detected magnetic resonance on optimized solar cells indicates that TEs are only present on the fullerenes. We conclude that in PTB7:PC71BM devices, TE formation via EBT is impacted by fullerene domain size at low temperature, but at room temperature, EBT does not represent a dominant loss pathway.
Mishra, Arjun K; Agnihotri, Pragati; Srivastava, Vijay Kumar; Pratap, J Venkatesh
2015-01-09
Polyamine biosynthesis pathway has long been considered an essential drug target for trypanosomatids including Leishmania. S-adenosylmethionine decarboxylase (AdoMetDc) and spermidine synthase (SpdSyn) are enzymes of this pathway that catalyze successive steps, with the product of the former, decarboxylated S-adenosylmethionine (dcSAM), acting as an aminopropyl donor for the latter enzyme. Here we have explored the possibility of and identified the protein-protein interaction between SpdSyn and AdoMetDc. The protein-protein interaction has been identified using GST pull down assay. Isothermal titration calorimetry reveals that the interaction is thermodynamically favorable. Fluorescence spectroscopy studies also confirms the interaction, with SpdSyn exhibiting a change in tertiary structure with increasing concentrations of AdoMetDc. Size exclusion chromatography suggests the presence of the complex as a hetero-oligomer. Taken together, these results suggest that the enzymes indeed form a heteromer. Computational analyses suggest that this complex differs significantly from the corresponding human complex, implying that this complex could be a better therapeutic target than the individual enzymes. Copyright © 2014 Elsevier Inc. All rights reserved.
Minois, N; Carmona-Gutierrez, D; Bauer, M A; Rockenfeller, P; Eisenberg, T; Brandhorst, S; Sigrist, S J; Kroemer, G; Madeo, F
2012-10-11
The naturally occurring polyamine spermidine (Spd) has recently been shown to promote longevity across species in an autophagy-dependent manner. Here, we demonstrate that Spd improves both survival and locomotor activity of the fruit fly Drosophila melanogaster upon exposure to the superoxide generator and neurotoxic agent paraquat. Although survival to a high paraquat concentration (20 mM) was specifically increased in female flies only, locomotor activity and survival could be rescued in both male and female animals when exposed to lower paraquat levels (5 mM). These effects are dependent on the autophagic machinery, as Spd failed to confer resistance to paraquat-induced toxicity and locomotor impairment in flies deleted for the essential autophagic regulator ATG7 (autophagy-related gene 7). Spd treatment did also protect against mild doses of another oxidative stressor, hydrogen peroxide, but in this case in an autophagy-independent manner. Altogether, this study establishes that the protective effects of Spd can be exerted through different pathways that depending on the oxidative stress scenario do or do not involve autophagy.
Breanna L. Riedel; Kevin R. Russell; W. Mark Ford; Katherine P. O' Neill; Harry W. Godwin
2008-01-01
Woodland salamander responses to either traditional grazing or silvopasture systems are virtually unknown. An information-theoretic modelling approach was used to evaluate responses of red-backed salamanders (Plethodon cinereus) to silvopasture and meadow conversions in southern West Virginia. Searches of area-constrained plots and artificial...
Bringing Knowledge Back In: Perspectives from Liberal Education
ERIC Educational Resources Information Center
Deng, Zongyi
2018-01-01
From the vantage point of liberal education, this article attempts to contribute to the conversation initiated by Michael Young and his colleagues on 'bringing knowledge back' into the current global discourse on curriculum policy and practice. The contribution is made through revisiting the knowledge-its-own-end thesis associated with Newman and…
The complex spine: the multidimensional system of causal pathways for low-back disorders.
Marras, William S
2012-12-01
The aim of this study was to examine the logic behind the knowledge of low-back problem causal pathways. Low-back pain and low-back disorders (LBDs) continue to represent the major musculoskeletal risk problem in the workplace,with the prevalence and costs of such disorders increasing over time. In recent years, there has been much criticism of the ability of ergonomics methods to control the risk of LBDs. Logical assessment of the systems logic associated with our understanding and prevention of LBDs. Current spine loading as well as spine tolerance research efforts are bringing the field to the point where there is a better systems understanding of the inextricable link between the musculoskeletal system and the cognitive system. Loading is influenced by both the physical environment factors as well as mental demands, whereas tolerances are defined by both physical tissue tolerance and biochemically based tissue sensitivities to pain. However, the logic used in many low-back risk assessment tools may be overly simplistic, given what is understood about causal pathways. Current tools typically assess only load or position in a very cursory manner. Efforts must work toward satisfying both the physical environment and the cognitive environment for the worker if one is to reliably lower the risk of low-back problems. This systems representation of LBD development may serve as a guide to identify gaps in our understanding of LBDs.
Detection of Norspermidine and Norspermine in Medicago sativa L. (Alfalfa) 1
Rodriguez-Garay, Benjamin; Phillips, Gregory C.; Kuehn, Glenn D.
1989-01-01
Shoot meristem tissues of alfalfa, Medicago sativa L., were found by high performance liquid chromatography analyses to contain the uncommon polyamines, norspermidine and norspermine. The chemical structures of norspermidine and norspermine, purified from alfalfa, were confirmed by comparison of mass spectra with those from authentic standards. The discovery of norspermidine and norspermine in alfalfa implicates the presence of at least two biosynthetic enzymes, a polyamine oxidase and a previously uncharacterized aminopropyltransferase. PMID:16666576
The importance of the specific Z-DNA structure and polyamines in carcinogenesis: fact or fiction.
Juranic, Z; Kidric, M; Tomin, R; Juranić, I; Spuzić, I; Petrović, J
1991-08-01
In this work some aspects of carcinogenesis are given. The importance of the emergence of Z or H DNA structure in the gene, or in the flanking gene sequences for the gene deletion and unusual gene recombination, is discussed. Some considerations on the role of selective pressure (of polyamines, of Mg2+, of the various levels of topoisomerase II, and of ATP) in the process of oncogene amplification, are given too.
Method for regenerating magnetic polyamine-epichlorohydrin resin
Kochen, Robert L.; Navratil, James D.
1997-07-29
Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.
Method for regenerating magnetic polyamine-epichlorohydrin resin
Kochen, R.L.; Navratil, J.D.
1997-07-29
Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately. 9 figs.
Perturbation of polyamine catabolism affects grape ripening of Vitis vinifera cv. Trincadeira.
Agudelo-Romero, Patricia; Ali, Kashif; Choi, Young H; Sousa, Lisete; Verpoorte, Rob; Tiburcio, Antonio F; Fortes, Ana M
2014-01-01
Grapes are economically the most important fruit worldwide. However, the complexity of biological events that lead to ripening of nonclimacteric fruits is not fully understood, particularly the role of polyamines' catabolism. The transcriptional and metabolic profilings complemented with biochemical data were studied during ripening of Trincadeira grapes submitted to guazatine treatment, a potent inhibitor of polyamine oxidase activity. The mRNA expression profiles of one time point (EL 38) corresponding to harvest stage was compared between mock and guazatine treatments using Affymetrix GrapeGen(®) genome array. A total of 2113 probesets (1880 unigenes) were differentially expressed between these samples. Quantitative RT-PCR validated microarrays results being carried out for EL 35 (véraison berries), EL 36 (ripe berries) and EL 38 (harvest stage berries). Metabolic profiling using HPLC and (1)H NMR spectroscopy showed increase of putrescine, proline, threonine and 1-O-ethyl-β-glucoside in guazatine treated samples. Genes involved in amino acid, carbohydrate and water transport were down-regulated in guazatine treated samples suggesting that the strong dehydrated phenotype obtained in guazatine treated samples may be due to impaired transport mechanisms. Genes involved in terpenes' metabolism were differentially expressed between guazatine and mock treated samples. Altogether, results support an important role of polyamine catabolism in grape ripening namely in cell expansion and aroma development. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Löser, C; Fölsch, U R; Mustroph, D; Cantor, P; Wunderlich, U; Creutzfeldt, W
1988-01-01
We investigated the trophic effect on the pancreas of male Wistar rats fed up to 20 days with either raw soybean flour (RSF) containing an active trypsin inhibitor or heat-inactivated soybean flour (HSF). The concentrations of the polyamines putrescine, spermidine, and spermine in the pancreas as well as cholecystokinin (CCK) concentrations in arterial and portal vein plasma were measured. Plasma CCK concentrations were measured by a sensitive radioimmunoassay specific for the sulfated region of CCK, whereas polyamine concentrations are determined by reversed phase high-performance liquid chromatography. The levels of CCK in both arterial and portal vein plasma were significantly higher in RSF- compared with HSF-fed rats, the concentration in the portal vein being twice as high compared with the aorta. A significant increase in pancreatic weight and protein content was positively correlated to an increase in putrescine and spermidine in the pancreas of RSF-fed rats compared with HSF-fed controls, whereas the spermine content did not differ between the two groups. The pancreatic DNA content in RSF-fed rats was significantly above control values of day 20 only. These data support the hypothesis that the trophic effect of soybean trypsin inhibitor on the pancreas is mediated by CCK and that polyamines might play an important role in CCK-induced pancreatic growth.
Green, Robert; Hanfrey, Colin C.; Elliott, Katherine A.; McCloskey, Diane E.; Wang, Xiaojing; Kanugula, Sreenivas; Pegg, Anthony E.; Michael, Anthony J.
2011-01-01
Summary We have identified gene fusions of polyamine biosynthetic enzymes S-adenosylmethionine decarboxylase (AdoMetDC, speD) and aminopropyltransferase (speE) orthologues in diverse bacterial phyla. Both domains are functionally active and we demonstrate the novel de novo synthesis of the triamine spermidine from the diamine putrescine by fusion enzymes from β-proteobacterium Delftia acidovorans and δ-proteobacterium Syntrophus aciditrophicus, in a ΔspeDE gene deletion strain of Salmonella enterica sv. Typhimurium. Fusion proteins from marine α-proteobacterium Candidatus Pelagibacter ubique, actinobacterium Nocardia farcinica, chlorobi species Chloroherpeton thalassium, and β-proteobacterium Delftia acidovorans each produce a different profile of non-native polyamines including sym-norspermidine when expressed in Escherichia coli. The different aminopropyltransferase activities together with phylogenetic analysis confirm independent evolutionary origins for some fusions. Comparative genomic analysis strongly indicates that gene fusions arose by merger of adjacent open reading frames. Independent fusion events, and horizontal and vertical gene transfer contributed to the scattered phyletic distribution of the gene fusions. Surprisingly, expression of fusion genes in E. coli and S. Typhimurium revealed novel latent spermidine catabolic activity producing non-native 1,3-diaminopropane in these species. We have also identified fusions of polyamine biosynthetic enzymes agmatine deiminase and N-carbamoylputrescine amidohydrolase in archaea, and of S-adenosylmethionine decarboxylase and ornithine decarboxylase in the single-celled green alga Micromonas. PMID:21762220