Polyamine Compounds Research Articles

A novel zinc-chelating compound has antifungal activity against a wide range of Candida species, including multidrug-resistant Candida auris.

In recent years, the incidence of invasive fungal infections has increased, resulting in considerable morbidity and mortality, particularly among immunocompromised individuals. Potential challenges in treating these infections with the few existing antifungal agents highlight the urgency of developing new ones. Here, we evaluated six alkyl polyamine compounds (APCs), not previously reported as antifungal drugs to our knowledge, that could deprive fungi of essential transition metals. The APC with confirmed antifungal activity against Candida spp. was analysed by using transcriptomics, followed by metal-addition experiments, mass spectrometric analyses and intracellular zinc quantification with a fluorescent probe. A cyclic APC with three pyridylmethyl groups, APC6, had high antifungal activity against a wide range of Candida species, including MDR Candida auris. We conclusively demonstrated that APC6 was able to capture zinc within fungal cells. APC6 not only exhibited activity against C. auris as a single agent but also enhanced the efficacy of an azole antifungal agent, voriconazole, in vitro and in vivo. APC6 disrupted the biofilms formed by Candida species. This zinc-chelating compound has potential as an antifungal agent, and the control of zinc levels in Candida species could be a powerful approach to treating drug-resistant candidiasis.

Optimization of hydrodynamic degumming of flax fiber for improved biochemical profile

Flax fibers have bioactive properties due to their biochemical composition. The quality of the fibers is the main parameter that determines the application, and the process of obtaining fibers has a crucial impact on the composition and properties of fibers. Therefore, this study aimed to enhance the quality of flax fibers by optimizing the hydrodynamic degumming process of decorticated flax fibers. Flax fibers, both non-transgenic (Nike) and transgenic (B14) fibers with overexpression of the β-1,3-glucanase gene from potato, were obtained through nine processes that varied in the degumming temperature, degumming time, and rinsing temperature. The content of phenolic, terpene and polyamine compounds as well as antioxidant activity was determined in the fibers. Two processes, due to having the highest content of bioactive compounds, were selected for further analyses: determination of the chemical composition and structure of plant cell walls, and in vitro tests on the culture of the V79 hamster lung fibroblast cell line. Both processes led to an increase in the content of cellulose and hemicellulose, along with a decrease in the amount of pectin in B14 fibers, indicating changes in the structure of the cell wall. Water extract containing phenolic compounds obtained from flax fiber resulted in increased viability of the V79 fibroblasts and did not show changes in the level of transcripts of inflammatory genes. Based on the obtained results, process VI was identified as the most effective for obtaining flax fibers of the best quality. Additionally, the study confirmed that transgenic B14 fibers exhibited better quality than non-transgenic fibers. The findings highlight the potential of the methods used to obtain flax fibers, which may significantly impact their properties.

The polyamine compound to response for biotic and abiotic stresses in Zea mays plant

Zea mays L. is the main multipurpose plant for feed energy, food and highly a susceptible for the environmental stresses to agricultural biotechnology. The plant triggers for the main factor in limited Z. mays yield. Recently, it was obtain a crop yields to be significan reduced, and stray due to environmental factor also biotic stresses. Moreover, it was confirm the security of live cells under non-adverse shapes, the polyamine compound was regulate most important roles to responses under abiotic and biotic stresses. The climate change for increasing to demand in maize production plants have been urged to increase for the stress in the tolerance investigation to that crop, although it was certainly realize and assignment of the polyamine compounds for responses for variety environmental stresses. In this study, we were describe a review and summarize the recent literature on the role for the polyamine compound with conferring stress tolerance to Z. mays plants. To the accumulation of polyamine compounds, that mechanism and behavior, recently to genetic the manipulation studied it was perform to pathway to the polyamine metabolism, it was improved the abiotic and biotic stress distance have been research. Then, the polyamine compound metabolism under stress term was not operate personally in that cells, and it was associated to other metabolic pathways in Z. mays plants. On the other hand, the complex joining and a role was a signaling to molecules have been reported.

Effect of polyamines and zeolites on the protein profile of leaves of the date palm cuttings Phoenix dactylifera L. grown under heavy metal stress conditions

This study was conducted on the five to six years old offshoots of date palm (Jebjab) cultivar planted in sustainable land, using an environment contaminated with heavy elements, with irrigation water contaminated with heavy elements Pb(NO3)2 300 mg.kg-1 and cadmium chloride CdCl2 3 mmol, as well as the comparison treatment. Then the treatment was with some polyamine compounds Putrescine 500 mg L-1, coumaric acid 500 mg L-1, and a zeolite compound at a rate of 10 kg Palm-1, in addition to the comparison treatment in the form of ground addition to the soil of the off shoots samples were taken from palm fronds, samples were dried using Freeze-dryer (Lyophilization technique), the protein was extracted from samples, and protein migration was carried out on Polyacrylamide gel using Slab-Electrophoresis method in the presence of SDS denaturants. The molecular weights of proteins were estimated and plotted using PhotoCapt Mw. The results of the study showed that the protein pattern of the leaves show up that all the trees of the study had taken part (identical) with the first protein bundle and the fifth protein bundle on the polyacrylamide gel, as the molecular weights of the proteins of the first bundle ranged between (222.136-243.750) kDa, while the molecular weights of the proteins of the bundle ranged. The fifth is between (24.843-50.386) kDa. This coincidence or participation in the molecular weights of the protein bundles of all the study trees may indicate that these trees belong to one plant origin (which is the Jebjab variety), as these plants share close molecular weights. Keywords: Date Palm, molecular weights, polyacrylamide gel, polyamine compounds.

Identification of polyamine compounds and characterization of polyamine oxidase from sheep's brain tissue

The study included partially purified of polyamine oxidase (PAO) from sheep's brain tissue by dialysis and ion exchange chromatography using DEAE-cellulose techniques. Isoenzymes (I and II) were obtained with specific activities 3.876 and 2.856 units/ mg of protein and purification folds 11 and 8 times respectively compared with crude enzyme.The specific activity of PAO I was better than PAO II, thus we considered it for following studying. The optimal conditions were 40 C and pH=9. Some of properties of partially purified PAO I enzyme were studied and the specificity was found to be superior to the substrate, where it was given the highest activity when using spermidine. The results showed the presence of cupper ion at a concentration of 0.1437 mg / mL in PAO I using an atomic absorption. The presence of the coenzyme conjugate flavin adenine dinucleotide (FAD) was also detected by using UV-Vis spectrum from (325-430) nm. The inhibitory effect of carbamazepine on the activity of homozygous PAO I was studied, and it was found that there was a decrease in the activity of the enzyme at different inhibitor concentrations. The type of inhibition of the drug was also studied, and it was found non-competitive, and that the value of the inhibition constant Ki was 1.8 mM. The polyamines in the crude extract of Sheep's brain were diagnosed with HPLC technique, and the results of the analysis indicated the presence of spermine, spermidine, cadavarin, diamino propane and hexylamine as well as the presence of other polymines.

SAR11 Cells Rely on Enzyme Multifunctionality To Metabolize a Range of Polyamine Compounds.

ABSTRACTIn the ocean surface layer and cell culture, the polyamine transport protein PotD of SAR11 bacteria is often one of the most abundant proteins detected. Polyamines are organic cations at seawater pH produced by all living organisms and are thought to be an important component of dissolved organic matter (DOM) produced in planktonic ecosystems. We hypothesized that SAR11 cells uptake and metabolize multiple polyamines and use them as sources of carbon and nitrogen. Metabolic footprinting and fingerprinting were used to measure the uptake of five polyamine compounds (putrescine, cadaverine, agmatine, norspermidine, and spermidine) in two SAR11 strains that represent the majority of SAR11 cells in the surface ocean environment, “Candidatus Pelagibacter” strain HTCC7211 and “Candidatus Pelagibacter ubique” strain HTCC1062. Both strains took up all five polyamines and concentrated them to micromolar or millimolar intracellular concentrations. Both strains could use most of the polyamines to meet their nitrogen requirements, but polyamines did not fully substitute for their requirements of glycine (or related compounds) or pyruvate (or related compounds). Our data suggest that potABCD transports all five polyamines and that spermidine synthase, speE, is reversible, catalyzing the breakdown of spermidine and norspermidine, in addition to its usual biosynthetic role. These findings provide support for the hypothesis that enzyme multifunctionality enables streamlined cells in planktonic ecosystems to increase the range of DOM compounds they metabolize.

Chitosan crosslinked with polyamine-co-melamine for adsorption of Hg2+: Application in purification of polluted water

A batch experiment was carried out in order to remove Hg2+ from the aqueous solution as well as the polluted water using modified chitosan (CS) with polyamine compounds (triethylenetetramine (TETA), tetraethylenepentamine (TEPA)), and melamine. The obtained polyamine-co-melamine crosslinked CS derivatives (MCS-4N and MCS-5N) were characterized and used as adsorbents. In comparison to the raw CS, the modification significantly promoted the adsorption of Hg2+ ions. The results of the pseudo-second-order kinetic model revealed that pH-dependent derivatives adsorbents achieved the equilibrium state within 12 h. The Langmuir model was best fitted with the Hg2+ adsorption isotherm and showed the highest adsorption capacities of 140.3 and 109.7 mg/g for MCS-4N and MCS-5N, respectively. A slight decrease in the adsorption efficiency of Hg2+ was noticed with the increment of the ionic strength of the solution. However, the studied adsorbents were easily regenerated and presented adequate reusability. The Hg2+ adsorption was regulated by the combined process of coordination reaction and electrostatic attraction as well. The as-prepared polyamine-co-melamine crosslinked CS derivatives were found potential adsorbents for the adsorptive capture of Hg2+ ions from aqueous solutions and polluted waters.

Evaluation of changes in fatty acid profile, grain, and oil yield of Carthamus tinctorius L. in response to foliar application of polyamine compounds under deficit irrigation conditions

Safflower is an oilseed plant rich source of omega 3 and 6 whose fatty acids composition may be affected by water deficit stress. Thus, filed experiments were conducted in Tehran, Iran during 2017 and 2018 growing seasons to investigate the influence of foliar application polyamines on fatty acid compositions and agronomic traits under deficit irrigation stress as a split plot with four replications. The studied treatments included irrigation at two levels of normal irrigation (I1, 50 %) and deficit irrigation at flowering stage (I2, 75 %) (irrigation after depletion of 50 % and 75 % moisture of field capacity, respectively) as the main plot and foliar application treatments at 10 levels included (water foliar application or control, foliar application putrescine, spermidine and spermine each in concentrations (50, 100, 200 μmol L−1)) as the subplot. Foliar application of putrescine under I2 enhanced grain and oil yield by 721.7 and 120.7 kg ha-1, respectively, on average in the two years of experiment compared with the control treatment. The total polyunsaturated and unsaturated fatty acids (∑PUFA and ∑UFA), UFA (omega 3 and 6), ratio of ∑PUFA to saturated fatty acids (∑SFA), harvest index and oil content rose under I2 conditions in both years of the experiment with spermine foliar application. Foliar application of putrescine also increased omega 6, ∑PUFA and ∑UFA under I1 conditions in both years. The results of this experiment indicate that foliar application of polyamines can improve grain and oil yield and quality of fatty acids of safflower under irrigation regimes.

Vapor phase assembly of urea–amine compounds and their protection against the atmospheric corrosion of carbon steel

Two kinds of polyamine compounds, bis-cyclohexylaminoethylurea (BCAU) and monocyclohexylaminoethylurea (MCAU), are synthesized via Mannich reaction. The anticorrosion films on carbon steel surface are prepared by the vapor phase assembly method. After 72 h volatilization at 50°C, the mass-loss for BCAU and MCAU in the closed space are 1.13% and 1.45%. The volatile-inhibiting sieve (VIS) test, the volatile-inhibiting ability test and the electrochemical impedance spectroscopy measurement are used to compare the prevention of the atmospheric corrosion by the assembly film. BCAU and MCAU have 92.44% and 87.56% inhibition efficiency for carbon steel in VIS test. On the basis of theoretical calculation and surface analysis, the protective film structures on carbon surface from the vapor phase assembly are proposed.

Polyamine-co-2, 6-diaminopyridine covalently bonded on chitosan for the adsorptive removal of Hg(II) ions from aqueous solution.

In the present study, 2, 6-diaminopyridine (PD) and polyamine compounds (ethylenediamine (EDA), triethylenetetramine (TETA), and tetraethylenepentamine (TEPA)) were used to modify chitosan (CS). The obtained derivatives (PD-CS, PD-EDA-CS, PD-TETA-CS, and PD-TEPA-CS) were identified and employed as adsorbents in batch experiments for the removal of Hg(II) from aqueous solutions. The results confirmed that successful modification improves the Hg(II) adsorption significantly compared to pristine CS. The adsorbed amounts of Hg(II) increased gradually and reached maxima at pH values above 4.0 for all derivatives. The Hg(II) adsorption equilibrium state was achieved within 12 h, with the process driven by a pseudo-second-order kinetic model. The Langmuir model effectively interpreted the Hg(II) adsorption isotherms; the maximum adsorption capacities for Hg(II) ions at 295 K were 172.7, 303.6, 276.0, and 230.6 mg/g for PD-CS, PD-EDA-CS, PD-TETA-CS, and PD-TEPA-CS, respectively. High temperature and low ionic strength favored Hg(II) adsorption. The Hg(II)-loaded CS derivative was easily regenerated and showed acceptable reusability. The further FT-IR and XPS analyses indicate that the Hg(II) adsorption is governed by a process combining electrostatic attraction and a coordination reaction. The CS derivatives produced from polyamine-co-2, 6-diaminopyridine covalently bonded onto CS are promising adsorbents for the adsorptive removal of Hg(II) from an aqueous solution.

Phosphorus Dendrimer Derived Solid Sorbents for CO2 Capture from Post-Combustion Gas Streams

Solid amine sorbents were prepared via cross-linking of polyamine compounds and polyaldehyde phosphorus dendrimers through a reductive amination approach. The CO2 adsorption capacities from inert gas streams and simulated flue gas were determined using a thermogravimetric analyzer (TGA) and a packed-bed reactor, (PBR) respectively. The sorbents adsorbed CO2 from inert CO2 gas streams up to 7.3 wt % at 65 °C and 10.7 wt % at 25 °C, while adsorbing CO2 from simulated flue gas up to 7.4 wt % at 65 °C. The amines are covalently bound in the sorbent, providing a robust material that is stable at elevated temperatures and does not leach upon exposure to moisture. The sorbents underwent extensive cycle testing, with no degradation observed up to 45 cycles on the TGA and up to 25 cycles on the PBR, while displaying rapid kinetics for both adsorption and desorption of CO2.

Tuning Zeolite Precursor Interactions by Switching the Valence of Polyamine Modifiers.

Nonclassical mechanisms of crystal growth often involve the formation of amorphous precursors that play a direct role in what is generally referred to as crystallization by particle attachment (or CPA). One of the most studied CPA systems in the literature is zeolite MFI, which is a microporous crystal with siliceous (silicalite-1) and aluminosilicate (ZSM-5) isostructures. The self-assembly, microstructural evolution, and mechanistic role of nanoparticle precursors (1-6 nm) during silicalite-1 crystallization have been the subjects of prior investigation by combined experimental and modeling techniques. Here we investigate for the first time the effects of zeolite growth modifiers (ZGMs) on MFI precursors. ZGMs are organic molecules that alter the anisotropic rate(s) of crystal growth as a means of tailoring crystal size and/or habit. We show that most ZGMs have little effect on precursor assembly and evolution during the prenucleation stages of silicalite-1 and ZSM-5 synthesis; however, studies at varying alkalinity reveal that pH can be used as a "switch" to tune ZGM speciation and concurrently the colloidal stability of precursors. This has been proven effective for various polyamine compounds, such as spermine, that exhibit divalent (positive) charge near negatively charged nanoparticle surfaces. Our finding is consistent with colloidal models that predict a higher concentration of divalent modifiers within the diffuse double layer surrounding the surfaces of (alumino)silicate precursors. Multivalent polyamines seemingly promote precursor-precursor aggregation at elevated temperature, which is consistent with a proposed hypothesis that modifiers with two or more sufficiently spaced cationic functional moieties are capable of bridging neighboring precursor surfaces, thus overcoming an electrostatic repulsive force that contributes to their colloidal stability. Given the importance of precursor-precursor and precursor-crystal interactions in zeolite nucleation and growth, respectively, our observations provide additional insight into the role of organics in zeolite crystallization.

Pacificimonas aurantium sp. nov., Isolated from the Seawater of the Pacific Ocean.

A Gram-negative bacterium, denoted JLT2012(T), was isolated from the surface water of the Pacific Ocean. This aerobic bacterium was rod shaped and devoid of flagella, displayed gliding motility, and grew in characteristic orange colonies. The bacterium contained ubiquinone Q-10 as the major respiratory quinone, and spermidine and spermine as the major polyamine compounds. The dominant fatty acids were C18:1ω7c and/or C18:1ω6c (34.7%), C16:0 (21.3%), and C18:0 (15.9%), whereas the polar lipids consisted mainly of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four sphingoglycolipids, and several unknown glycolipids. The G+C content DNA was found to be 65.5mol%. Comparative 16S rRNA gene sequence analysis revealed that strain JLT2012(T) formed a distinct lineage within the genus Pacificimonas (formerly known asPacificamonas) and shared the highest sequence similarity with the type strain of Pacificimonas flava JLT2015(T) (96.0%). Data combined from different studies on the phenotypic, phylogenetic, and genomic characteristics indicated that strain JLT2012(T) is a representative of a novel species within Pacificimonas for which the name Pacificimonas aurantium sp. nov. (type strain JLT2012(T)=LMG 27361(T)=CGMCC 1.12399(T)) is proposed.

Role of polyamines in abiotic stress responses.

Abstract Many secondary metabolites in plants are involved in a range of plant physiological processes including abiotic stress tolerance. Major polyamine (PA) compounds including putrescine (Put), spermidine (Spd) and spermine (Spm) have structural, functional and regulatory activities that allow them to play a major role in abiotic stress tolerance. A thorough understanding of PA function in plant stress tolerance is important for improving plant stress responses, breeding, biomarker development and other purposes. In this review, I discuss the role of PA in several types of abiotic stress and the mechanisms associated with dynamic changes in PA content. Major methods to evaluate PA function are discussed including biosynthetic gene expression, exogenous application of PA, use of PA biosynthesis inhibitors, transgenic manipulation and development of gain or loss of function mutants.

An outbreak of swimming-pool related respiratory symptoms: An elusive source of trichloramine in a municipal indoor swimming pool.

Several members of a swimming club complained of respiratory symptoms associated with attending a municipal indoor swimming pool. Trichloramine, a volatile chlorination by-product and a potent respiratory irritant, was the most probable culprit, but the exact cause for its presence in excessive concentrations remained elusive. Twenty-two competitive swimmers and six coaches were evaluated during the outbreak and nine swimmers and four coaches were re-evaluated one year later. Symptoms were recorded by non-standardized history taking; pulmonary function testing included spirometry, measurement of fraction of exhaled nitric oxide (FENO) and histamine provocation. Concentrations of trichloramine in air were measured repeatedly by the method of Héry. The most commonly reported symptoms consisted of cough (n=16), dyspnoea (n=13), tearing eyes (n=10) and blocked or runny nose (n=6). Mean FEV1% predicted was 109.1%. Mean FENO level was 19.7 ppb (higher than 25 ppb in 3 subjects). Airway hyperreactivity to histamine (PC20 ≤ 8 mg/ml) was detected in 22/26 subjects. Measured trichloramine concentrations in air exceeded the maximal concentration (WHO) of 0.5mg/m(3) four times between May and October 2011 and four times between January and March 2012. Polyamine compounds, present in glue used for repairing pipework, were identified as a probable external source of nitrogen resulting in increasing trichloramine concentrations. After the removal of the presumed cause of the excessive trichloramine concentrations, most subjects improved clinically, but several subjects remained symptomatic and had bronchial hyperreactivity. A high prevalence of airway hyperreactivity, accompanied by symptoms of upper and lower airways, was detected in swimmers who had been repeatedly exposed to high trichloramine concentrations. A glue containing polyamines, used to repair a pipework, was suspected to be the source of this excessive production of trichloramine.

Molecular Determinants of Substrate Selectivity in OCT3 (SLC22A3)

Organic cation transporters (OCTs) are polyspecific, facilitative transporters with major roles in metabolite and drug clearance. OCT1 and OCT2 are expressed in hepatocytes and proximal tubular cells, whereas OCT3 is in astrocytes. OCT1 and OCT2 have been well-studied, but the pharmacology and structure-function relationships of OCT3 remain obscure. Previously, we screened polyamine compounds for transport and competition against model substrate methyl-4-phenylpyridinium (MPP+) in OCT-expressing Xenopus oocytes, and established that polyamines are transported substrates for OCTs, and that hydrophobicity is a principal requirement for recognition of polycationic substrates and inhibitors. OCT3 exhibited significantly higher requirements for hydrophobicity than other isoforms. Here, we investigated the implications of key residues in shaping the distinct selectivity profile of rat and human OCT3. Homology modeling identified a putative hydrophobic cleft in OCTs capable of accommodating a wide variety of structures and that all isoforms share a conserved Asp within this pocket (D478). Replacement of this residue with Arg, Asn or even Glu drastically reduced MPP+ uptake, suggesting that this Asp residue is obligatory for OCT3-mediated transport, and may help stabilize positively charged substrates. Several key residues within the OCT1 and OCT2 binding pocket are not conserved in OCT3, and these differences might account for more stringent requirements in OCT3. Mutations at these sites in OCT3 to the corresponding residue in OCT1 and OCT2 (L166F, F450L and E451Q) intrinsically decreased MPP+ uptake rate. Potent OCT1 and OCT2 blockers tetraethylammonium (TEA) and 1,10-diaminodecane (DA10) interact weakly with wild-type OCT3. There was no enhancement of TEA or DA10 block in mutant OCT3; rather, MPP+ uptake rate increased in presence of these compounds. These results suggest that these residues may help stabilize substrates within the transporter and imply a more complex interaction between substrates than simple competition for a single site.

Changes of polyamine pattern in digestive glands of mussel Mytilus galloprovincialis under exposure to cadmium

Polyamines, in particular spermidine and spermine, have been identified as important antioxidants, highly induced by oxidative stress in a variety of organisms. However, little is known about changes in polyamine content of metal-stressed marine organisms. In the present study, mussels (Mytilus galloprovincialis) were experimentally exposed to 25μg/L Cd2+ or 100μg/L Cd2+ for up to 15days. Cd2+ was progressively accumulated in mussel tissues, leading to a characteristic oxidative-stress status. Free putrescine (PUT) production was noticeably induced in response to Cd2+ at day 5 and then declined. In contrast, free spermidine (SPD) content was gradually reduced, whereas the concentration of free spermine (SPM) increased. In combination, these changes led to a 69% or 88% reduction in the ratio of (SPD+SPM)/PUT at day 5, dependent on the Cd2+ concentration used, which subsequently followed an upward trend in values, albeit not reaching those of controls. Conjugated polyamines constantly increased, in particular conjugated spermidine and spermine, tagging along with metallothionein production. Acetylated polyamines showed a diverse profile of changes, but their content was generally kept at low levels throughout the exposure period. Collectively, our results suggest that certain polyamine compounds could play a significant role in the tolerance of mussels against Cd2+-mediated stress, and that the ratio (SPD+SPM)/PUT could be a good indicator of the metal-stress status.

Molecular Chlorambucil-Methionine Conjugate: Novel Anti-cancer Agent against Breast MCF-7 Cell Model

Breast cancer is the most common type of cancer in women worldwide and it is the second cause of cancer death after lung cancer. There have been many efforts in producing various pharmaceuticals for breast cancer treatment and among them Nanopharmaceutical Sciences have been extremely of high importance. All the drugs used to treat a cancer were usually shown unpleasant side effects. Chlorambucil is an older antineoplastic (anticancer) drug that is an alkylating agent with many known side effects for the patients. Recent findings have shown that the uptake of polyamine compounds such as amino acids (e.g. Methionine) in cancer cells is mostly increased. In this study a molecular antineoplastic conjugate, Chlorambucil-Methionine was developed and evaluated on the breast cancer MCF-7 cell line. For evaluation MTT assay, apoptosis assay and necrosis assay were employed but the mechanism of cell death or toxicity comparison were investigated by apoptosis-necrosis assay or abnormal toxicity test. Chlorambucil-Methionine as a targeted antineoplastic conjugate has shown higher antineoplastic properties and had not shown abnormal toxicity. The conjugate showed very good anticancer effects same as Chlorambucil but it had less toxicity in comparison with Chlorambucil. Apoptosis was the mechanism for most cell death in this study. Based on the results Chlorambucil-Methionine conjugate may be a better option than Chlorambucil alone for the treatment of breast cancer. Further study is recommended to confirm these findings in clinical practice.

In situ proteo-metabolomics reveals metabolite secretion by the acid mine drainage bio-indicator, Euglena mutabilis

Euglena mutabilis is a photosynthetic protist found in acidic aquatic environments such as peat bogs, volcanic lakes and acid mine drainages (AMDs). Through its photosynthetic metabolism, this protist is supposed to have an important role in primary production in such oligotrophic ecosystems. Nevertheless, the exact contribution of E. mutabilis in organic matter synthesis remains unclear and no evidence of metabolite secretion by this protist has been established so far. Here we combined in situ proteo-metabolomic approaches to determine the nature of the metabolites accumulated by this protist or potentially secreted into an AMD. Our results revealed that the secreted metabolites are represented by a large number of amino acids, polyamine compounds, urea and some sugars but no fatty acids, suggesting a selective organic matter contribution in this ecosystem. Such a production may have a crucial impact on the bacterial community present on the study site, as it has been suggested previously that prokaryotes transport and recycle in situ most of the metabolites secreted by E. mutabilis. Consequently, this protist may have an indirect but important role in AMD ecosystems but also in other ecological niches often described as nitrogen-limited.

Preliminary Dynamics Analysis for Synthesis of Polyamide Polyamine Compounds (PPC)

In this paper, preliminary dynamics analysis of synthesis of polyamide polyamine compounds was deduced by kinetic equation. The dynamic analysis shows that the reaction of polyethylene polyamines with adipic acid belongs to typical three reactions. In the kinetic equation, the concentration of carboxyl failed to reflect the ability of provided protons that reaction system to amine.