Putrescine

The present study was designed to analyze the regulation of the levels of the polyamines and their biosynthetic enzymes during embryonic development of Xenopus laet:is. The activity of omithine decarboxylase (ODC), a rate-controlling enzyme in polyamine biosynthesis, is elevated until, during gastrulation, there is a precipitous drop in activity. This is not attributable to a decrease in ODC mRNA content and polysome profiles reveal no apparent decrease in ODC message associated with polysomes. ODC synthesis seems to be maintained at a low, relatively constant rate until neurulation whereupon ribosome loading of ODC mRNA increases. During gastrulation the rate of ODC degradation increases dramatically, which can account for the decrease in ODC. S-Adenosylmethionine decarboxylase (AdoMetDC), another rate-controlling enzyme in polyamine biosynthesis, shows a low and constant activity from cleavage to neurulation. Subsequently, the AdoMetDC activity increases dramatically. The changes in AdoMetDC activity parallel the changes in AdoMetDC mRNA levels, suggesting a transcriptional control of AdoMetDC expression during this developmental period. The activities of ODC and AdoMetDC produce a steady increase in putrescine and spermidine content of the embryo. The spermine content also increases until gastrulation, but then decreases until the tailbud stage. . Fax: + 46 90 16669 I. 0167-4781/95/$09.50 © 1995 Elsevier Science B.V. All rights reserved SSDI 01 67-4781 (95)001 36-0

Polyamines play a critical role in the development of intestinal and immune systems during the infant breastfeeding period, but the effect of polyamines on the microbiota has not been reported. The aim of our study was to characterize the impact on the colonization pattern in neonatal BALB/cOlaHsd mice after supplementing an infant formula (IF) with a mixture of putrescine (PUT), spermidine (SPD) and spermine (SPM). A total of 48 pups (14 days old) were randomly assigned to 4-day intervention groups as follows: breast-fed (unweaned) pups (n=12); weaned pups (n=12) fed an infant formula (IF); weaned pups (n=12) fed an IF enriched with a low concentration of PUT, SPD and SPM (2.10, 22.05 and 38.00 μg/day, respectively); and weaned pups (n=12) fed with IF enriched with a high concentration of PUT, SPD and SPM (8.40, 88.20 and 152.00 μg/day, respectively) of polyamines in accordance with normal proportions found in human milk. Microbiota composition was analyzed by fluorescent in situ hybridization (FISH) with flow cytometry detection. Microbiota changes in formula-fed mice were significantly greater following supplementation with polyamines (Pb.01). Bifidobacterium group bacteria, Akkermansia-like bacteria and Lactobacillus-Enterococcus group levels were higher in the groups fed infant formula supplemented with polyamines, resulting in even higher numbers of bacteria than in the breastfed pups. Our findings indicate that infant formulas enriched with polyamines may interact with gut microbiota, suggesting that further studies in human infants are required to assess the impact of polyamines on both growth and microbiota levels.

Here, we report the engineering of the industrially relevant Corynebacterium glutamicum for putrescine production. C. glutamicum grew well in the presence of up to 500 mM of putrescine. A reduction of the growth rate by 34% and of biomass formation by 39% was observed at 750 mM of putrescine. C. glutamicum was enabled to produce putrescine by heterologous expression of genes encoding enzymes of the arginine-and ornithine decarboxylase pathways from Escherichia coli. The results showed that the putrescine yield by recombinant C. glutamicum strains provided with the arginine-decarboxylase pathway was 40 times lower than the yield by strains provided with the ornithine decarboxylase pathway. The highest production efficiency was reached by overexpression of speC, encoding the ornithine decarboxylase from E. coli, in combination with chromosomal deletion of genes encoding the arginine repressor ArgR and the ornithine carbamoyltransferase ArgF. In shake-flask batch cultures this strain produced putrescine up to 6 g/L with a space time yield of 0.1 g/L/h. The overall product yield was about 24 mol% (0.12 g/g of glucose).

Rhodococcus fascians is a gram-positive phytopathogen that induces differentiated galls, known as leafy galls, on a wide variety of plants, employing virulence genes located on a linear plasmid. The pathogenic strategy consists of the production of a mixture of six synergistically acting cytokinins that overwhelm the plant's homeostatic mechanisms, ensuring the activation of a signaling cascade that targets the plant cell cycle and directs the newly formed cells to differentiate into shoot meristems. The shoots that are formed upon infection remain immature and never convert to source tissues resulting in the establishment of a nutrient sink that is a niche for the epiphytic and endophytic R. fascians subpopulations. Niche formation is accompanied by modifications of the transcriptome, metabolome, physiology, and morphology of both host and pathogen. Here, we review a decade of research and set the outlines of the molecular basis of the leafy gall syndrome.

Biogenic amines (BAs) represent a considerable toxicological risk in some food products. Putrescine is one of the most common BAs in food. Its increased occurrence in food may lead to alimentary poisoning, due to enhancement of the toxic effects of other BAs, and also to lower quality of food, this amine is potentially carcinogenic. Increased occurrence of putrescine in food is mainly due to the bacterial metabolism of the Gram-negative as well as Gram-positive bacteria present. The bacterial metabolism of putrescine is very specific due to its complexity (in comparison with the metabolism of other BAs). There are 3 distinct known pathways leading toward the formation of putrescine, in some splices involving up to 6 different enzymes. The existence of more metabolic pathways and the possibility of their simultaneous use by different bacteria complicate the specification of the best conditions for food production and storage, which could lead to a lower content of putrescine. This review provides a summary of the existing knowledge about putrescine production and detection (mainly detection of specific genes for different enzymes using polymerase chain reaction) in both starter and contaminating microorganisms. Thus, this comprehensive review gives a useful overview for further research.

A novel dinuclear cobalt(III) complex with the condensation product of 2-acetylpyridine and malonic acid dihydrazide, N′,N′2-bis[(1E)-1-(2-pyridyl)ethylidene]propanedihydrazide was synthesized and characterized by elemental analysis, spectroscopy (NMR and infrared), and X-ray crystal analysis. The complex showed a moderate activity towards Artemia salina. The highest cytotoxic potential of the complex was observed on the epithelial breast cancer (MDA-361) cell line. The investigated complex induced apoptosis, the early apoptotic cells comprising 28.18%, compared to 5.64% of control cells in the same phase. The interaction of the complex with calf thymus DNA (CT-DNA) was monitored by blue shift and hyperchromism in the UV–vis spectra. The observed intrinsic binding constant (Kb = 4.2 × 105 M− 1) together with structural analysis of the complex indicate the groove binding.A novel binuclear cobalt(III) complex with the condensation product of 2-acetylpyridine and malonic acid dihydrazide was synthesized and characterized. The complex showed biological activity, including cytotoxity to MDA-361 breast cancer cell line, induced apoptosis, and bound to DNA.► A dinuclear Co(III) complex with the condensation product of 2-acetylpyridine and malonic acid dihydrazide. ► Cytotoxic action to the epithelial breast cancer MDA-361 cell line. ► Induction of apoptosis by the complex. ► DNA groove binding of the complex.

In this paper we describe the synthesis and characterization of a series of simple spermine/ amino acid conjugates, some of which potently inhibit the uptake of spermidine into MDA-MB-231 breast cancer cells. The presence of an amide in the functionalized polyamine appeared to add to the affinity for the polyamine transporter. The extensive biological characterization of an especially potent analogue from this series, the Lys-Spm conjugate (31), showed this molecule will be an extremely useful tool for use in polyamine research. It was shown that the use of 31 in combination with DFMO led to a cytostatic growth inhibition of a variety of cancer cells, even when used in the presence of an extracellular source of transportable spermidine. It was furthermore shown that this combination effectively reduced the cellular levels of putrescine and spermidine while not affecting the levels of spermine. These facts together with the nontoxic nature of 31 make it a novel lead for further anticancer development.

Some lactic acid bacteria (LAB) isolated from fermented foods have been proven to degrade biogenic amines through the production of amine oxidase enzymes. Since little is known about this in relation to wine micro-organisms, this work examined the ability of LAB strains (n=85) isolated from wines and other related enological sources, as well as commercial malolactic starter cultures (n=3) and type strains (n=2), to degrade histamine, tyramine and putrescine. The biogenic amine-degrading ability of the strains was evaluated by RP-HPLC in culture media and wine malolactic fermentation laboratory experiments. Although at different extend, 25% of the LAB isolates were able to degrade histamine, 18% tyramine and 18% putrescine, whereas none of the commercial malolactic starter cultures or type strains were able to degrade any of the tested amines. The greatest biogenic amine-degrading ability was exhibited by 9 strains belonging to the Lactobacillus and Pediococcus groups, and most of them were able to simultaneously degrade at least two of the three studied biogenic amines.

Biotechnological uses of plant cell-tissue culture usually rely on constitutive transgene expression. However, such expression of transgenes may not always be desirable. In those cases, the use of an inducible promoter could be an alternative approach. To test this hypothesis, we developed two binary vectors harboring a stress-inducible promoter from Arabidopsis thaliana, driving the β-glucuronidase reporter gene and the oat arginine decarboxylase. Transgenic hairy roots of Lotus corniculatus were obtained with osmotic-and cold-inducible β-glucuronidase and arginine decarboxylase activities. The increase in the activity of the latter was accompanied by a significant rise in total free polyamines level. Through an organogenesis process, we obtained L. corniculatus transgenic plants avoiding deleterious phenotypes frequently associated with the constitutive over-expression of arginine decarboxylation and putrescine accumulation.

Synthesis, characterization, cytotoxic activity and crystal structures of tri-and di-organotin(IV) complexes constructed from the b-{[(E)-1-(2hydroxyaryl)alkylidene]amino}propionate and b-{[(2Z)-(3-hydroxy-1methyl-2-butenylidene)]amino}propionate skeletons Abstract Reactions of potassium b-{[(E)-1-(2-hydroxyaryl)alkylidene]amino}propionates (L 1 HK-L 3 HK) and potassium b-{[(2Z)-(3-hydroxy-1-methyl-2-butenylidene)]amino}propionate (L 4 HK) with R These complexes have been characterized by 1 H, 13 C, 119 Sn NMR, ESI-MS, IR and 119m Sn Mö ssbauer spectroscopic techniques in combination with elemental analyses. The crystal structures of 1, 4, 5 and 6 were determined. In the solid state, compound 1 is a one-dimensional polymer built from SnPh 3 moieties bridged by single carboxylate ligands, but two alternating modes of bridging are present along the polymeric chain. Compound 4 is also a one-dimensional polymer built from SnBu 3 moieties bridged by the two carboxylate O-atoms of a single ligand, but only one mode of bridging is present. Di-n-butyltin compounds 5 and 6 are centrosymmetric tetranuclear bis(dicarboxylatotetrabutyldistannoxane) complexes containing a planar Sn 4 O 2 core in which two l 3 -oxo O-atoms connect an Sn 2 O 2 ring to two exocyclic Sn-atoms. The four carboxylate ligands display two different modes of coordination where both modes involve bridging of two Sn-atoms. The solution structures were predicted by 119 Sn NMR spectroscopy. The in vitro cytotoxic activity of compound 5 against WIDR, M19 MEL, A498, IGROV, H226, MCF7 and EVSA-T human tumor cell lines is reported.

One hundred and sixty-three wines from La Rioja, Utiel-Requena, and Tarragona were analyzed to determine if there were any differences in the concentrations of six biogenic amines that are found in these three regions. The influence of grape variety, type of vinification, wine pH, malolactic fermentation, and storage in bottle on biogenic amine concentrations was studied. Results show important differences in putrescine and histamine concentrations among regions, varieties of grape, and type of wine; differences were less appreciable for the remaining biogenic amines studied. Low pH prevented biogenic amine formation. Malolactic fermentation and short storage periods in bottle (3-6 months) showed increases in histamine concentration, whereas longer periods of storage led to a general decrease in histamine. Several strains of lactic acid bacteria were isolated in this work, and their ability to form biogenic amines was assayed in synthetic media, grape must, and wine. Grape varieties, different types of winemaking, pH, and lactic acid bacteria may be responsible for the differences observed in the biogenic amine concentrations of the wines analyzed.

Paraquat is still a widely used herbicide in several countries. Its toxic action on plants occurs through a one-electron reduction interfering with the photosynthesis process. By a similar reaction, the herbicide may induce peroxidation processes in non-target animal species. Furthermore, paraquat may interfere with the cellular transport of polyamines. The aim of this work was to investigate some aspects related to paraquat-induction of oxidative stress (lipoperoxidation, enzymatic activities of catalase and superoxide dismutase) and also the levels of polyamines (putrescine, spermidine and spermine) in two species of freshwater invertebrates, the oligochaete Lumbriculus variegatus and the gastropod Biomphalaria glabrata. The results showed that both organisms elicited differential responses. In addition, the data suggested that polyamines may play an important role against lipoperoxidation processes.

To ascertain the role of spermidine/spermine N-1acetyl-transferase (SSAT; the rate-limiting enzyme in polyamine catabolism) in cell injury, cultured kidney (HEK 293) cells conditionally overexpressing SSAT were generated. The SSAT expression was induced and its enzymatic activity increased 24 h after addition of tetracycline and remained elevated over the length of the experiments. Induction of SSAT upregulated the expression of polyamine oxidase and resulted in the reduction of cellular concentration of spermidine and spermine, increased concentration of putrescine, and inhibited cell growth. SSAT overexpression increased the expression of heme oxygenase-1 (HO-1) by 350% 24 h after addition of tetracycline, indicating the induction of oxidative stress. The presence of catalase significantly prevented the upregulation of HO-1 in SSAT overexpressing cells, indicating that generation of H 2 O 2 is partially responsible for the induction of oxidative stress. Overexpression of SSAT caused rounding and loss of cell anchorage and significantly altered the morphology of actin-containing filopodia, suggesting an adhesion defect. SSAT upregulation may mediate majority of the oxidative stress in kidney ischemia-reperfusion injury (IRI) as manifested by decreased cell growth, generation of toxic metabolites (H 2 O 2 and putrescine), upregulation of HO-1, disruption of cell anchorage, and defect in cell adhesion. These data point to the inhibition of polyamine catabolism as a therapeutic approach for the prevention of tissue injury in kidney IRI.

Aim:  To evaluate the biodiversity of lactobacilli from slightly fermented sausages (chorizo, fuet and salchichon) by molecular typing, while considering their safety aspects.Methods and Results:  Species-specific PCR, plasmid profiling and randomly amplified polymorphic DNA (RAPD)-PCR were used to characterize 250 lactic acid bacteria (LAB) isolated from 21 low acid Spanish fermented sausages. Lactobacillus sakei was the predominant species (74%) followed by Lactobacillus curvatus (21·2%) and Leuconostoc mesenteroides (4·8%). By plasmid profiling and RAPD-PCR 144 different strains could be differentiated, 112 belonging to Lact. sakei, 23 to Lact. curvatus and 9 to Leuc. mesenteroides. Ion-pair high performance liquid chromatography was used to detect biogenic amine production. Tyramine and phenylethylamine were produced by 14·4 and 12·4% of the isolates, respectively, all belonging to the species Lact. curvatus. The production of tyramine was stronger than that of phenylethylamine. Partial sequencing of the tyrosine decarboxylase gene from Lact. curvatus was achieved. A specific PCR assay to detect the Lact. curvatus tyramine-producers was designed. The disc diffusion test was used to detect antibiotic resistance among the isolates. Most isolates displayed resistance to vancomycin and gentamicin. Only four strains were resistant to most of the antibiotics tested. None of the isolates were resistant to erythromycin.Conclusions: Lactobacillus sakei would be the species of choice for further use as starter culture in fermented sausage production. Strain typing and characterization of biogenic amine production together with antibiotic susceptibility testing for the selection of starter cultures could help to increase the quality and safety of the products.Significance and Impact of the Study:  Species-specific PCR, RAPD and plasmid profiling proved to be efficient at typing LAB at species and strain level. Information on biogenic amine production and transferable antibiotic resistance is important in order to avoid selection of strains with undesirable properties as starter cultures.

Depletion of intracellular polyamine pools invariably inhibits cell growth. Although this is usually accomplished by inhibiting polyamine biosynthesis, we reasoned that this might be more effectively achieved by activation of polyamine catabolism at the level of spermidine/spermine N 1 -acetyltransferase (SSAT); a strategy first validated in MCF-7 breast carcinoma cells. We now examine the possibility that, due to unique aspects of polyamine homeostasis in the prostate gland, tumor cells derived from it may be particularly sensitive to activated polyamine catabolism. Thus, SSAT was conditionally overexpressed in LNCaP prostate carcinoma cells via a tetracycline-regulatable (Tet-off) system. Tetracycline removal resulted in a rapid ϳ10-fold increase in SSAT mRNA and an increase of ϳ20-fold in enzyme activity. SSAT products N 1 -acetylspermidine, N 1 -acetylspermine, and N 1 ,N 12 -diacetylspermine accumulated intracellularly and extracellularly. SSAT induction also led to a growth inhibition that was not accompanied by polyamine pool depletion as it was in MCF-7 cells. Rather, intracellular spermidine and spermine pools were maintained at or above control levels by a robust compensatory increase in ornithine decarboxylase and S-adenosylmethionine decarboxylase activities. This, in turn, gave rise to a high rate of metabolic flux through both the biosynthetic and catabolic arms of polyamine metabolism. Treatment with the biosynthesis inhibitor ␣-difluoromethylornithine during tetracycline removal interrupted flux and prevented growth inhibition. Thus, flux-induced growth inhibition appears to derive from overaccumulation of metabolic products and/or from depletion of metabolic precursors. Metabolic effects that were not excluded as possible contributing factors include high levels of putrescine and acetylated polyamines, a 50% reduction in S-adenosylmethionine, and a 45% decline in the SSAT cofactor acetyl-CoA. Overall, the study demonstrates that activation of polyamine catabolism in LNCaP cells elicits a compensatory increase in polyamine biosynthesis and downstream metabolic events that culminate in growth inhibition.

The cellular polyamines putrescine, spermidine, and spermine accelerate the aggregation and fibrillization of ␣-synuclein, the major protein component of Lewy bodies associated with Parkinson's disease. Circular dichroism and fluorometric thioflavin T kinetic studies showed a transition of ␣-synuclein from unaggregated to highly aggregated states, characterized by lag and transition phases. In the presence of polyamines, both the lag and transition times were significantly shorter. All three polyamines accelerated the aggregation and fibrillization of ␣-synuclein to a degree that increased with the total charge, length, and concentration of the polyamine. Electron and scanning force microscopy of the reaction products after the lag phase revealed the presence of aggregated particles (protofibrils) and small fibrils. At the end of the transition phase, ␣-synuclein formed long fibrils in all cases, although some morphological variations were apparent. In the presence of polyamines, fibrils formed large networks leading ultimately to condensed aggregates. In the absence of polyamines, fibrils were mostly isolated. We conclude that the polyamines at physiological concentrations can modulate the propensity of ␣-synuclein to form fibrils and may hence play a role in the formation of cytosolic ␣-synuclein aggregates.

A Gram-stain-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacterium (strain 280 T ) isolated from a chicken was studied for its taxonomic allocation. 16S rRNA gene sequence analyses clearly allocated the isolate in the genus Paenochrobactrum group with a 16S rRNA gene sequence similarity of 98.8 % to the currently recognized species, Paenochrobactrum gallinarii and Paenochrobactrum glaciei. This allocation was confirmed by the fatty acid data (major fatty acids: C 18 : 1 v7c and C 19 : 0 cyclo v8c) and a polyamine pattern with the major compound putrescine and relatively high amounts of spermidine. Also, the polar lipid profile with phosphatidylethanolamine, phosphatiylmonomethylethanolamine, phosphatidylglycerol, phosphatidylcholine and the genus-specific 'stretched aminolipid' was well in line with the description of the genus Paenochrobactrum. The quinone system consisted predominantly of ubiquinone Q-10 with traces of Q-9 and Q-11. DNA-DNA hybridization of strain 280 T with Paenochrobactrum gallinarii Sa25 T and Paenochrobactrum glaciei KMM 3858 T showed relatedness values of 38.8 % (reciprocal 20.2 %) and 30.2 % (reciprocal 29.8 %), respectively. These results in combination with differentiating physiological and biochemical data clearly showed that strain 280 T merits species status. We propose the name Paenochrobactrum pullorum sp. nov. to accommodate this strain with the type strain 280 T (5LMG 28095 T 5CIP 110700 T ).

BioLure, a synthetic food attractant for Mediterranean fruit ßy [Ceratitis capitata (Wiedemann)], is composed of three chemicals (ammonium acetate, trimethylamine hydrochloride, and putrescine). We deployed these components together and in separate MultiLure traps across predominantly native forests, non-native forests, farmlands, orchards, and residential areas on the islands of Hawaii and Maui, to evaluate attraction of C. capitata and nontarget insects. Large numbers (as many as 186 per trap per day) of mainly saprophagous nontarget ßies (primarily Drosophilidae, Chloropidae, Lonchaeidae, Neriidae, Otitidae, and Calliphoridae) were attracted to BioLure. Very few predators, parasitoids, or pollinators were attracted. Native species, predominantly drosophilid and calliphorid ßies, were attracted in large numbers in endemic forests, but mostly (at least 88%) introduced species were collected in orchards, backyards, and non-native forest. A comparison of attraction to the three separate components versus combined components in traps revealed that ammonium acetate and, to a lesser extent, putrescine are the key components attractive to nontarget species. Omitting the putrescine ingredient from BioLure did not drastically decrease C. capitata catches but reduced nontarget captures by 20%.

The polyamines, spermine and spermidine -small organic polycations that are absolutely required for eukaryotic cell growth -are shown here to function in Trypanosoma cruzi epimastigotes, as protectors of membrane lipoperoxidation by reactive oxygen species generated either by H 2 O 2 /Fe 2+ or nifurtimox. In vitro, spermine and spermidine inhibited lipoperoxidation in a dose dependent manner. Spermine was more efficient than spermidine in its inhibitory effect. Lipid peroxidation induced by H 2 O 2 showed an IC 50 of 0.55 mM for spermine and 0.9 mM for spermidine while an IC 50 of 0.8 mM for spermine and 1.5 mM for spermidine were observed when lipoperoxidation was elicited by nifurtimox. Likewise in vivo, both exogenously added spermine and spermidine or endogenous increase of spermine levels induced by phorbol ester, protected against lipoperoxidation and decreased citotoxicity provoked by nifurtimox. Putrescine and cadaverine, also present in T. cruzi had no effect at all. None of the polyamines had any effect neither on the scavenging of superoxide anion nor on the regulation of antioxidant enzymes such as superoxide dismutase and peroxidases involved in H 2 O 2 detoxification.

Studies of the molecular basis of microbial metabolic activities that are important for the changes in food quality are valuable in order to help in understanding the behavior of spoiling bacteria in food. The growth of a psychrotrophic Serratia proteamaculans strain was monitored in vitro and in artificially inoculated raw beef. Two growth temperatures (25°C and 4°C) were tested in vitro, while growth at 15°C and 4°C was monitored in beef. During growth, the expression of inducible lysine and ornithine-decarboxylase genes was evaluated by quantitative reverse transcription-PCR (qRT-PCR), while the presence of cadaverine and putrescine was quantified by LC-ESI-MS/MS. The expression of the decarboxylase genes, and the consequent production of cadaverine and putrescine were shown to be influenced by the temperature, as well as by the complexity of the growth medium. Generally, the maximum gene expression and amine production took place during the exponential and early stationary phase, respectively. In addition, lower temperatures caused slower growth and gene downregulation. Higher amounts of cadaverine compared to putrescine were found during growth in beef with the highest concentrations corresponding to microbial loads of ca. 9 CFU/g. The differences found in gene expression evaluated in vitro and in beef suggested that such activities are more reliably investigated in situ in specific food matrices.

Grapevine (Vitis species) is the most economically important fruit crop worldwide. Ripening of nonclimacteric fruits such as grapes has been the subject of intense research. Despite this interest, little is known on the role played by polyamines in the onset of ripening of non-climacteric fruits. These growth regulators have been involved in plant development and stress responses.

In this work, production of the biogenic amines histamine, tyramine and putrescine by a collection of 74 lactic acid bacteria (LAB) of aquatic origin has been investigated by means of three different methodologies: agar plate assay in decarboxylase differential growth medium, thin-layer chromatography (TLC) and PCR. None of the evaluated LAB strains showed neither production of histamine and putrescine, nor presence of the genetic determinants encoding the corresponding decarboxylase activities. However, the tyrosine decarboxylase gene (tyrDC) was present in all the enterococcal strains, and tyramine production was detected by TLC in all of them but in E. faecium BCS59 and MV5. Analysis of the tyrosine decarboxylase operon of these strains revealed the presence of an insertion sequence upstream tyrDC that could be responsible for their lack of tyrosine decarboxylase activity.

The present work investigated whether polyamines play a role in the control of the innate immune response in the brain. The first evidence that these molecules may be involved in such a process was based on the robust increase in the expression of the first and rate-limiting enzyme of biosynthesis of polyamines during immune stimuli. Indeed, systemic lipopolysaccharide (LPS) administration increased ornithine decarboxylase (ODC) mRNA and protein within neurons and microglia across the mouse central nervous system (CNS). This treatment was also associated with a robust and transient transcriptional activation of genes encoding pro-inflammatory cytokines and toll-like receptor 2 (TLR2) in microglial cells. The endotoxin increased the cerebral activity of ODC, which was abolished by a suicide inhibitor of ODC. The decrease in putrescine levels largely prevented the ability of LPS to trigger tumor necrosis factor α and TLR2 gene transcription in the mouse brain. In contrast, expression ...

A highly selective, sensitive, specific and rapid electrochemical putrescine biosensor was constructed by covalently immobilizing diamine oxidase purified from Pisum sativum  leaves on polypyrrole 3-carboxylic acid (PPy-3C) with zinc oxide nanoparticles ( ZnONps) using N-ethyl-N-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxy succinimide (NHS) modified platinum electrode.Transmission electron microscopy (TEM), X-ray diffraction (XRD), UV spectroscopy and Dynamic light scattering (DLS) were used for characterization of ZnONps. The modified enzyme electrode was characterized by cyclic voltammetry (CV), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and electrochemical impedance spectroscopy (EIS).The experimental variables that can affect the putrescine amperometric response, such as the applied potential, pH and temperature have been optimized to perform a selective determination of putrescine.The optimized putrescine biosensor showed linear response range of 0.1–750µM and rapid response within 4s at a potential of 0.4V vs Ag/AgCl. The sensitivity was approximately 40µA/mM/cm2 with a detection limit of 0.1µM. Proposed putrescine biosensor was successfully applied to cancer patients urine sample, which correlated well with a standard enzymic colorimetric method (r = 0.98).

Unlike other eukaryotes, which synthesize polyamines (PA) only from ornithine, plants possess an additional pathway utilizing arginine as a precursor. In this study, we have identified cDNA clones coding for a Glycine max ornithine decarboxylase (ODC, EC 4.1.1.7) and an arginine decarboxylase (ADC, EC 4.1.1.19). Expression analysis using semi-quantitative RT-PCR approach revealed that both genes coding for enzymes involved in putrescine biosynthesis (ODC and ADC) were found in most plant organs examined. Significant expression levels of both genes were detected in root tips and hypocotyls. The spatial distribution of GmODC and GmADC transcripts in primary and lateral roots and hypocotyls revealed that these genes are co-expressed in expanding cells of cortex parenchyma, expanding cells of central cylinder in main roots and in developing tissues and expanding cells of soybean hypocotyls. The data point out a correlation of the expression patterns of GmODC and GmADC gene to certain physiological roles such as organ development and cell expansion.

A Gram-staining-negative, rod-shaped, non-spore-forming bacterium, designated strain E103 T , was isolated from the skin of the medical leech Hirudo verbana. 16S rRNA gene sequence analysis showed that the isolate was closely related to species of the genus Castellaniella. Castellaniella ginsengisoli DCY36 T was shown to be the most closely related (98.4 % 16S rRNA gene sequence similarity), followed by Castellaniella denitrificans NKNTAU T and Castellaniella daejeonensis MJ06 T (both 97.8 %), then Castellaniella caeni Ho-11 T (97.5 %). Chemotaxonomic data (major ubiquinone, Q-8; major polar lipids, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylserine; predominant polyamine, putrescine with a moderate amount of 2hydroxyputrescine; and major fatty acids, C 17 : 0 cyclo, C 16 : 0 and summed feature 4 comprising C 16 : 1 v7c and/or iso-C 15 : 0 2-OH) supported the affiliation of the isolate to the genus Castellaniella. DNA-DNA hybridization values with the type strains of all species of the genus Castellaniella were 23 % (reciprocal, 18 %) with C. ginsengisoli KCTC 22398 T , 20 % (26 %) with C. daejeonensis KCTC 22454 T , 11 % (58 %) with C. denitrificans DSM 11046 T and 13 % (12 %) with C. caeni KCTC 12197 T . Phenotypic differentiation of strain E103 T from its closest neighbours was possible. Strain E103 T therefore represents a novel species of the genus Castellaniella, for which the name Castellaniella hirudinis sp. nov. is proposed, with the type strain E103 T (5CCUG 62394 T 5LMG 26910 T ).

Biogenic amines (BA) are toxic nitrogenous compounds that can be accumulated in foods via the microbial decarboxylation of certain amino acids. Lactic acid bacteria (LAB) strains belonging to different species and genera have been described as BA producers and are mainly responsible for their synthesis in fermented foods. It is generally accepted that the capacity to produced BAs is strain-dependent. However, the large number of enterococci identified as BA producers suggests that the aminogenic trait may be a species-level characteristic. Enterococcus faecalis, Enterococcus faecium and Enterococcus durans strains of different origin were analysed to determine their capacity to produce tyramine and putrescine. The presence of the genes responsible for this and the identity of their flanking regions were checked by PCR. The results suggest that tyramine biosynthesis is a species-level characteristic in E. faecalis, E. faecium and E. durans. Putrescine synthesis was found to be a species-level trait of E. faecalis, with production occurring via the agmatine deamination pathway. Some E. faecium strains of human origin also produced putrescine; this trait was probably acquired via horizontal gene transfer.

The polyamines spermidine, spermine, and putrescine are known to be deeply linked with growth processes, gene expression, and extracellular matrix synthesis. Their cellular content depends primarily on the activity of the enzyme ornithine decarboxylase. High levels of ornithine decarboxylase and polyamines have been found in proliferative, inflammatory, and neoplastic pathologies of the oral cavity and in gingival fluid. Difluoromethylornithine (DFMO) selectively inhibits ornithine decarboxylase, thus depleting polyamine content and preventing cell proliferation and synthesis activity. The aim of this study was to investigate whether DFMO treatment could modify the genes involved in cell proliferation and extracellular matrix turnover.

As a result of bioassay-guided fractionation, betulinic acid, a pentacyclic triterpene, was identified as a melanoma-specific cytotoxic agent. In follow-up studies conducted with athymic mice carrying human melanomas, tumour growth was completely inhibited without toxicity. As judged by a variety of cellular responses, antitumour activity was mediated by the induction of apoptosis. Betulinic acid is inexpensive and available in abundant supply from common natural sources, notably the bark of white birch trees. The compound is currently undergoing preclinical development for the treatment or prevention of malignant melanoma.

Polyamines are essential for cell proliferation; therefore, we hypothesized that arginase I or arginase II activities, via production of ornithine for polyamine synthesis, may be limiting for proliferation of endothelial cells (EC). Bovine coronary venular EC stably transfected with a lacZ gene (lacZ-EC, control), rat arginase I cDNA (AI-EC), or mouse arginase II cDNA (AII-EC) were utilized to test this hypothesis. Cell-proliferation assays showed that EC proliferation was markedly increased in AI-EC and AII-EC compared with lacZ-EC. Expression of proliferating cell nuclear antigen was also enhanced in AI-EC and AII-EC. DL-alpha-difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase, was used to establish that increased polyamine synthesis was involved in mediating the enhanced growth of AI-EC and AII-EC. Addition of 5 mM DFMO to the culture medium completely abolished the differences in cellular putrescine concentrations and reduced the differences in ...

Cadaver dogs are trained on a variety of materials, including artificial or pseudo scents. The chemical components of commercially available pseudo scents are not known, so their accuracy as a decomposition odour mimic and their effectiveness as a canine training aid have not been evaluated. Two pseudo scents that are commercially available and used for training cadaver dogs were analysed using comprehensive two-dimensional gas chromatography–time of flight mass spectrometry (GC×GC–TOFMS). The two formulations were determined to be simplistic in their composition, compared to real cadaveric volatile organic compound (VOC) mixtures, with only a few major components. The enhanced GC×GC–TOFMS peak capacity was nevertheless useful to discriminate less intense peaks from large overloaded peaks. The availability of both dimension retention times combined with the peak finding and deconvolution algorithm, enabled the chemical characterization of the two formulations. Additionally, high resolution (HR) TOFMS was used to extract molecular formulae and confirm identities of analytes. The seven compounds identified by this work have not been reported previously as volatile products of decomposition, indicating that these pseudo scents are not to be considered as an accurate representation of cadaveric decomposition odour. Further research on the olfaction of scent detection canines and the chemical composition of their target odourants needs to be conducted to develop improved canine training aids.

Biogenic amines have been implicated in a malabsorption syndrome characterized by decreases in feed efficiency and enlargement of the proventriculus. Two studies were conducted to determine the effects of two common biogenic amines, histamine (HIS) and cadaverine (CAD), on broiler growth and the incidence of pathologies associated with proventriculitis. In the first experiment, broiler chicks were fed diets containing 0, 0.01, 0.05, 0.1, and 0.2% HIS, and in the second experiment chicks were fed diets containing 0, 0.1, and 0.2% HIS, 0.1% CAD, or a combination of 0.1% HIS and 0.1% CAD. Histamine at 0.1 and 0.2% or the combination of HIS and CAD (0.1% each) reduced body weight and feed conversion at 21 d of age. Histamine (0.2%) or the combination of 0.1% HIS and 0.1% CAD increased the circum-(Key words: biogenic amine, broiler, histamine, cadaverine, proventriculitus) 2001 Poultry Science 80:906-911 Abbreviation Key: CAD = cadaverine; HIS = histamine; PVG = proventriculus + gizzard. by guest on September 24, 2015 http://ps.oxfordjournals.org/ Downloaded from

Decarboxylation pathways are widespread among lactic acid bacteria; their physiological role is related to acid resistance through the regulation of the intracellular pH and to the production of metabolic energy via the generation of a proton motive force and its conversion into ATP. These pathways include, among others, biogenic amine (BA) production pathways. BA accumulation in foodstuffs is a health risk; thus, the study of the factors involved in their production is of major concern. The analysis of several lactic acid bacterial strains isolated from different environments, including fermented foods and beverages, revealed that the genes encoding these pathways are clustered on the chromosome, which suggests that these genes are part of a genetic hotspot related to acid stress resistance. Further attention was devoted to the ornithine decarboxylase pathway, which affords putrescine from ornithine. Studies were performed on three lactic acid bacteria belonging to different species. The ODC pathway was always shown to be involved in cytosolic pH alkalinisation and acid shock survival, which were observed to occur with a concomitant increase in putrescine production.

The first CO-releasing metallodendrimers, based on polypyridyl dendritic scaffolds functionalized with Mn(CO) 3 moieties, of the general formula [DAB-PPI-{MnBr-(bpy CH3,CHN )(CO) 3 } n ], where DAB = 1,4-diaminobutane, PPI = poly(propyleneimine), bpy = bipyridyl, and n = 4 for firstor n = 8 for second-generation dendrimers, were synthesized and comprehensively characterized by analytical (HR-ESI mass spectrometry and elemental analysis) and spectroscopic ( 1 H, 13 C{ 1 H}-NMR, infrared, and UV/vis spectroscopy) methods. The CO-release properties of these compounds were investigated in pure buffer and using the myoglobin assay. Both metallodendrimer generations are stable in the dark in aqueous buffer for up to 16 h but show photoactivated CO release upon excitation at 410 nm, representing a novel class of macromolecular photoactivatable CO-releasing molecules (PhotoCORMs). No scaling effects were observed since both metallodendrimers release ∼65% of the total number of CO ligands per molecule, regardless of the generation number. In addition, the mononuclear model complex [MnBr(bpy CH3,CHNCH2CH2CH3 )(CO) 3 ] was prepared and comprehensively studied, including DFT/TDDFT calculations. These metallodendrimer-based PhotoCORMs afford new methods of targeted delivery of large amounts of carbon monoxide to cellular systems.

Endogenous free polyamines (PAs), putrescine, spermidine and spermine, from developing fruitlets of Citrus species (Citrus unshiu Marc. and Citrus clementina Hort ex Tanaka) which differ in their parthenocarpic ability, and from uniflowered leafy and leafless inflorescences differing in their ability to set, have been determined by dansylation and separation of dansyl derivatives by HPLC. No significant differences in PAs content were observed between species or between leafy and leafless inflorescences which, nevertheless, significantly differed in fruit set. However, significant differences in their content were found in developing fruitlets, depending on the preceding flowering intensity of the tree and on the fruitlet load. These results suggest that, in Citrus, PAs may act as a nitrogen source rather than a regulator of fruit set.