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Sample records for nitrosomonas europaea reporter

  1. Transformations of aromatic compounds by nitrosomonas europaea

    SciTech Connect

    Keener, W.K.; Arp, D.J.

    1994-06-01

    The soil bacterium Nitrosomonas europaea is an obligate autotroph which uses O2 as an electron acceptor and ammonia as its sole natural energy source. The ubiquity of nitrifying bacteria may facilitate their use in bioremediation applications, but such applications will require a thorough knowledge of the substrate range of Ammonia monooxygenase (AMO) (catalyzing the oxidation of ammonia). This study extends the know substrate range of N. europaea to include alkylbenzenes, halobenzenes, and various N- and O-containing aromatics. Evidence is also presented that oxidation of p-cresol and ring-substituted benzylic alcohols to corresponding aldehydes joccures even in the absence of AMO activity. 33 refs., 7 figs.

  2. Chemoorganoheterotrophic growth of Nitrosomonas europaea and Nitrosomonas eutropha.

    PubMed

    Schmidt, Ingo

    2009-08-01

    The ammonia oxidizers Nitrosomonas europaea and Nitrosomonas eutropha are able to grow chemoorganotrophically under anoxic conditions with pyruvate, lactate, acetate, serine, succinate, alpha-ketoglutarate, or fructose as substrate and nitrite as terminal electron acceptor. The growth yield of both bacteria is about 3.5 mg protein (mmol pyruvate)(-1) and the maximum growth rates of N. europaea and N. eutropha are 0.094 d(-1) and 0.175 d(-1), respectively. In the presence of pyruvate and CO2 about 80% of the incorporated carbon derives from pyruvate and about 20% from CO2. Pyruvate is used as energy and only carbon source in the absence of CO2 (chemoorganoheterotrophic growth). CO2 stimulates the chemoorganotrophic growth of both ammonia oxidizers and the expression of ribulose bisphosphate carboxylase/oxygenase is down-regulated at increasing CO2 concentration. Ammonium, although required as nitrogen source, is inhibitory for the chemoorganotrophic metabolism of N. europaea and N. eutropha. In the presence of ammonium pyruvate consumption and the expression of the genes aceE, ppc, gltA, odhA, and ppsA (energy conservation) as well as nirK, norB, and nsc (denitrification) are reduced.

  3. Structure of the Nitrosomonas Europaea Rh Protein

    SciTech Connect

    Li, X.; Jayachandran, S.; Nguyen, H.-H.T.; Chan, M.K.

    2009-06-01

    Amt/MEP/Rh proteins are a family of integral membrane proteins implicated in the transport of NH3, CH(2)NH2, and CO2. Whereas Amt/MEP proteins are agreed to transport ammonia (NH3/NH4+), the primary substrate for Rh proteins has been controversial. Initial studies suggested that Rh proteins also transport ammonia, but more recent evidence suggests that they transport CO2. Here we report the first structure of an Rh family member, the Rh protein from the chemolithoautotrophic ammonia-oxidizing bacterium Nitrosomonas europaea. This Rh protein exhibits a number of similarities to its Amt cousins, including a trimeric oligomeric state, a central pore with an unusual twin-His site in the middle, and a Phe residue that blocks the channel for small-molecule transport. However, there are some significant differences, the most notable being the presence of an additional cytoplasmic C-terminal alpha-helix, an increased number of internal proline residues along the transmembrane helices, and a specific set of residues that appear to link the C-terminal helix to Phe blockage. This latter linkage suggests a mechanism in which binding of a partner protein to the C terminus could regulate channel opening. Another difference is the absence of the extracellular pi-cation binding site conserved in Amt/Mep structures. Instead, CO2 pressurization experiments identify a CO2 binding site near the intracellular exit of the channel whose residues are highly conserved in all Rh proteins, except those belonging to the Rh30 subfamily. The implications of these findings on the functional role of the human Rh antigens are discussed.

  4. High cell density cultivation of the chemolithoautotrophic bacterium Nitrosomonas europaea.

    PubMed

    Papp, Benedek; Török, Tibor; Sándor, Erzsébet; Fekete, Erzsébet; Flipphi, Michel; Karaffa, Levente

    2016-05-01

    Nitrosomonas europaea is a chemolithoautotrophic nitrifier, a gram-negative bacterium that can obtain all energy required for growth from the oxidation of ammonia to nitrite, and this may be beneficial for various biotechnological and environmental applications. However, compared to other bacteria, growth of ammonia oxidizing bacteria is very slow. A prerequisite to produce high cell density N. europaea cultures is to minimize the concentrations of inhibitory metabolic by-products. During growth on ammonia nitrite accumulates, as a consequence, N. europaea cannot grow to high cell concentrations under conventional batch conditions. Here, we show that single-vessel dialysis membrane bioreactors can be used to obtain substantially increased N. europaea biomasses and substantially reduced nitrite levels in media initially containing high amounts of the substrate. Dialysis membrane bioreactor fermentations were run in batch as well as in continuous mode. Growth was monitored with cell concentration determinations, by assessing dry cell mass and by monitoring ammonium consumption as well as nitrite formation. In addition, metabolic activity was probed with in vivo acridine orange staining. Under continuous substrate feed, the maximal cell concentration (2.79 × 10(12)/L) and maximal dry cell mass (0.895 g/L) achieved more than doubled the highest values reported for N. europaea cultivations to date.

  5. Detection and characterization of a multicopper oxidase from Nitrosomonas europaea.

    PubMed

    Lawton, Thomas J; Rosenzweig, Amy C

    2011-01-01

    Blue copper oxidase (BCO) is a multicopper oxidase (MCO) found in Nitrosomonas europaea as well as in other ammonia-oxidizing organisms. In this chapter, we detail methods used to detect, isolate, and characterize BCO from N. europaea. A method for identifying and classifying MCOs commonly found in nitrifiers based on primary sequence is also described.

  6. A Specific Inorganic Triphosphatase from Nitrosomonas europaea

    PubMed Central

    Delvaux, David; Murty, Mamidanna R. V. S.; Gabelica, Valérie; Lakaye, Bernard; Lunin, Vladimir V.; Skarina, Tatiana; Onopriyenko, Olena; Kohn, Gregory; Wins, Pierre; De Pauw, Edwin; Bettendorff, Lucien

    2011-01-01

    The CYTH superfamily of proteins is named after its two founding members, the CyaB adenylyl cyclase from Aeromonas hydrophila and the human 25-kDa thiamine triphosphatase. Because these proteins often form a closed β-barrel, they are also referred to as triphosphate tunnel metalloenzymes (TTM). Functionally, they are characterized by their ability to bind triphosphorylated substrates and divalent metal ions. These proteins exist in most organisms and catalyze different reactions depending on their origin. Here we investigate structural and catalytic properties of the recombinant TTM protein from Nitrosomonas europaea (NeuTTM), a 19-kDa protein. Crystallographic data show that it crystallizes as a dimer and that, in contrast to other TTM proteins, it has an open β-barrel structure. We demonstrate that NeuTTM is a highly specific inorganic triphosphatase, hydrolyzing tripolyphosphate (PPPi) with high catalytic efficiency in the presence of Mg2+. These data are supported by native mass spectrometry analysis showing that the enzyme binds PPPi (and Mg-PPPi) with high affinity (Kd < 1.5 μm), whereas it has a low affinity for ATP or thiamine triphosphate. In contrast to Aeromonas and Yersinia CyaB proteins, NeuTTM has no adenylyl cyclase activity, but it shares several properties with other enzymes of the CYTH superfamily, e.g. heat stability, alkaline pH optimum, and inhibition by Ca2+ and Zn2+ ions. We suggest a catalytic mechanism involving a catalytic dyad formed by Lys-52 and Tyr-28. The present data provide the first characterization of a new type of phosphohydrolase (unrelated to pyrophosphatases or exopolyphosphatases), able to hydrolyze inorganic triphosphate with high specificity. PMID:21840996

  7. Dissecting iron uptake and homeostasis in Nitrosomonas europaea.

    PubMed

    Sayavedra-Soto, Luis A; Vajrala, Neeraja; Arp, Daniel J

    2011-01-01

    The chemolithoautotroph Nitrosomonas europaea oxidizes about 25 mol of NH(3) for each mole of CO(2) that is converted to biomass using an array of heme and nonheme Fe-containing proteins. Hence mechanisms of efficient iron (Fe) uptake and homeostasis are particularly important for this Betaproteobacterium. Among nitrifiers, N.europaea has been the most studied to date. Characteristics that make N.europaea a suitable model to study Fe uptake and homeostasis are as follows: (a) its sequenced genome, (b) its capability to grow relatively well in 0.2 μM Fe in the absence of heterologous siderophores, and (c) its amenability to mutagenesis. In this chapter, we describe the methodology we use in our laboratory to dissect Fe uptake and homeostasis in the ammonia oxidizer N. europaea.

  8. Test Medium for the Growth of Nitrosomonas europaea

    PubMed Central

    Sato, Chikashi; Schnoor, Jerald L.; McDonald, Donald B.; Huey, Jon

    1985-01-01

    A mineral medium for studying the growth of Nitrosomonas europaea was developed and examined. The medium was defined in terms of chemical speciation by using chemical equilibrium computer models. The medium significantly increased the metabolic activity of the organisms compared with previously developed media, yielding a specific growth rate as high as 3.0 day−1 (generation time, 5.5 h). The specific growth rate was enhanced by increasing the inoculum and was linearly correlated with the inoculum-to-total-culture volume ratio on a semilog scale. A reproducible growth rate for N. europaea was obtained with this medium under controlled experimental conditions. PMID:16346783

  9. Global analysis of the Nitrosomonas europaea iron starvation stimulon.

    PubMed

    Vajrala, Neeraja; Sayavedra-Soto, Luis A; Bottomley, Peter J; Arp, Daniel J

    2012-04-01

    The importance of iron to the metabolism of the ammonia-oxidizing bacterium Nitrosomonas europaea is well known. However, the mechanisms by which N. europaea acquires iron under iron limitation are less well known. To obtain insight into these mechanisms, transcriptional profiling of N. europaea was performed during growth under different iron availabilities. Of 2,355 N. europaea genes on DNA microarrays, transcripts for 247 genes were identified as differentially expressed when cells were grown under iron limitation compared to cells grown under iron-replete conditions. Genes with higher transcript levels in response to iron limitation included those with confirmed or assigned roles in iron acquisition. Genes with lower transcript levels included those encoding iron-containing proteins. Our analysis identified several potentially novel iron acquisition systems in N. europaea and provided support for the primary involvement of a TonB-dependent heme receptor gene in N. europaea iron homeostasis. We demonstrated that hemoglobin can act as an iron source under iron-depleted conditions for N. europaea. In addition, we identified a hypothetical protein carrying a lipocalin-like domain that may have the ability to chelate iron for growth in iron-limited media.

  10. Solid-Phase Contact Assay That Uses a lux-Marked Nitrosomonas europaea Reporter Strain To Estimate Toxicity of Bioavailable Linear Alkylbenzene Sulfonate in Soil

    PubMed Central

    Brandt, Kristian K.; Pedersen, Anders; Sørensen, Jan

    2002-01-01

    Information about in situ toxicity of the bioavailable pools of adsorptive soil pollutants is a prerequisite for proper ecological risk assessment in contaminated soils. Such toxicity data may be obtained by assays allowing for direct exposure of introduced test microorganisms to the toxicants, as they appear in solid solution equilibria in the natural soil. We describe a novel sensitive solid-phase contact assay for in situ toxicity testing of soil pollutants based on a recombinant bioluminescent reporter strain of Nitrosomonas europaea. A slurry of the reporter strain and soil sample was shaken for 1 h, after which bioluminescence was measured either directly (soil slurry protocol) or in the supernatant obtained after centrifugation (soil extract protocol). The assay was validated for both protocols by using linear alkylbenzene sulfonate (LAS) as a toxic and adsorptive model compound in the soil samples. Interestingly, LAS showed the same toxicity to the reporter strain with either soil incubation (both protocols) or pure culture, suggesting that adsorbed LAS pools contributed to the observed toxicity. The solid-phase contact assay that used the reporter strain of lux-marked N. europaea was slightly more sensitive for the detection of LAS toxicity in soil than activity-based assays targeting indigenous nitrifiers and much more sensitive than assays targeting indigenous heterotrophic microbes. We conclude that the new solid-phase contact assay, which is based on direct interaction of the test microorganisms with bioavailable pools of the toxicants in soil, provides a most sensitive and relevant method for evaluating the in situ toxicity and assessing the risks of soil contaminants. PMID:12089034

  11. Global transcriptional response of Nitrosomonas europaea to chloroform and chloromethane.

    PubMed

    Gvakharia, Barbara O; Permina, Elizabeth A; Gelfand, Mikhail S; Bottomley, Peter J; Sayavedra-Soto, Luis A; Arp, Daniel J

    2007-05-01

    Upon exposure of Nitrosomonas europaea to chloroform (7 microM, 1 h), transcripts for 175 of 2,460 genes were found at higher levels in treated cells than in untreated cells and transcripts for 501 genes were found at lower levels. With chloromethane (3.2 mM, 1 h), transcripts for 67 genes were at higher levels and transcripts for 148 genes were at lower levels. Transcripts for 37 genes were at higher levels following both treatments and included genes for heat shock proteins, sigma-factors of the extracytoplasmic function subfamily, and toxin-antitoxin loci. N. europaea has higher levels of transcripts for a variety of defense genes when exposed to chloroform or chloromethane.

  12. Gene expression profiles of Nitrosomonas europaea, an obligate chemolitotroph

    SciTech Connect

    Daniel J. Arp

    2005-05-25

    Nitrosomonas europaea is an aerobic lithoautotrophic bacterium that uses ammonia (NH3) as its energy source. As a nitrifier, it is an important participant in the nitrogen cycle, which can also influence the carbon cycle. The focus of this work was to explore the genetic structure and mechanisms underlying the lithoautotrophic growth style of N. europaea. Whole genome gene expression: The gene expression profile of cells in exponential growth and during starvation was analyzed using microarrays. During growth, 98% of the genes increased in expression at least two fold compared to starvation conditions. In growing cells, approximately 30% of the genes were expressed eight fold higher, Approximately 10% were expressed more than 15 fold higher. Approximately 3% (91 genes) were expressed to more than 20 fold of their levels in starved cells. Carbon fixation gene expression: N. europaea fixes carbon via the Calvin-Benson-Bassham (CBB) cycle via a type I ribulose bisphosphate carboxylase/oxygenase (RubisCO). This study showed that transcription of cbb genes was up-regulated when the carbon source was limited, while amo, hao and other energy harvesting related genes were down-regulated. Iron related gene expression: Because N. europaea has a relatively high content of hemes, sufficient Fe must be available in the medium for it to grow. The genome revealed that approximately 5% of the coding genes in N. europaea are dedicated to Fe transport and assimilation. Nonetheless, with the exception of citrate biosynthesis genes, N. europaea lacks genes for siderophore production. The Fe requirements for growth and the expression of the putative membrane siderophore receptors were determined. The N. europaea genome has over 100 putative genes ({approx}5% of the coding genes) related to Fe uptake and its siderophore receptors could be grouped phylogenetically in four clusters. Fe related genes, such as a number of TonB-dependent Fe-siderophore receptors for ferrichrome and

  13. Gene expression profiles of Nitrosomonas europaea, an obligate chemolitotroph

    SciTech Connect

    Daniel J Arp

    2005-06-15

    Nitrosomonas europaea is an aerobic lithoautotrophic bacterium that uses ammonia (NH3) as its energy source. As a nitrifier, it is an important participant in the nitrogen cycle, which can also influence the carbon cycle. The focus of this work was to explore the genetic structure and mechanisms underlying the lithoautotrophic growth style of N. europaea. Whole genome gene expression. The gene expression profile of cells in exponential growth and during starvation was analyzed using microarrays. During growth, 98% of the genes increased in expression at least two fold compared to starvation conditions. In growing cells, approximately 30% of the genes were expressed eight fold higher, Approximately 10% were expressed more than 15 fold higher. Approximately 3% (91 genes) were expressed to more than 20 fold of their levels in starved cells. Carbon fixation gene expression. N. europaea fixes carbon via the Calvin-Benson-Bassham (CBB) cycle via a type I ribulose bisphosphate carboxylase/oxygenase (RubisCO). This study showed that transcription of cbb genes was up-regulated when the carbon source was limited, while amo, hao and other energy harvesting related genes were down-regulated. Iron related gene expression. Because N. europaea has a relatively high content of hemes, sufficient Fe must be available in the medium for it to grow. The genome revealed that approximately 5% of the coding genes in N. europaea are dedicated to Fe transport and assimilation. Nonetheless, with the exception of citrate biosynthesis genes, N. europaea lacks genes for siderophore production. The Fe requirements for growth and the expression of the putative membrane siderophore receptors were determined. The N. europaea genome has over 100 putative genes ({approx}5% of the coding genes) related to Fe uptake and its siderophore receptors could be grouped phylogenetically in four clusters. Fe related genes, such as a number of TonB-dependent Fe-siderophore receptors for ferrichrome and

  14. The transcription of the cbb operon in Nitrosomonas europaea.

    PubMed

    Wei, Xueming; Sayavedra-Soto, Luis A; Arp, Daniel J

    2004-06-01

    Nitrosomonas europaea is an aerobic ammonia-oxidizing bacterium that participates in the C and N cycles. N. europaea utilizes CO(2) as its predominant carbon source, and is an obligate chemolithotroph, deriving all the reductant required for energy and biosynthesis from the oxidation of ammonia (NH(3)) to nitrite (). This bacterium fixes carbon via the Calvin-Benson-Bassham (CBB) cycle via a type I ribulose bisphosphate carboxylase/oxygenase (RubisCO). The RubisCO operon is composed of five genes, cbbLSQON. This gene organization is similar to that of the operon for 'green-like' type I RubisCOs in other organisms. The cbbR gene encoding the putative regulatory protein for RubisCO transcription was identified upstream of cbbL. This study showed that transcription of cbb genes was upregulated when the carbon source was limited, while amo, hao and other energy-harvesting-related genes were downregulated. N. europaea responds to carbon limitation by prioritizing resources towards key components for carbon assimilation. Unlike the situation for amo genes, NH(3) was not required for the transcription of the cbb genes. All five cbb genes were only transcribed when an external energy source was provided. In actively growing cells, mRNAs from the five genes in the RubisCO operon were present at different levels, probably due to premature termination of transcription, rapid mRNA processing and mRNA degradation.

  15. Characterization of the ferrioxamine uptake system of Nitrosomonas europaea.

    PubMed

    Wei, Xueming; Sayavedra-Soto, Luis A; Arp, Daniel J

    2007-12-01

    The chemolithoautotroph Nitrosomonas europaea has two genes predicted to encode outer-membrane (OM) ferrioxamine transporters. Expression of the ferrioxamine uptake system required induction, as shown by the shorter lag phase in ferrioxamine-containing cultures when ferrioxamine-exposed cells were used as an inoculum. The two OM ferrioxamine siderophore transporters encoded by foxA(1) (NE1097) and foxA(2) (NE1088) were produced only in cells grown in Fe-limited ferrioxamine-containing medium. The inactivation of foxA(1), singly or in combination with foxA(2), prevented growth in Fe-limited medium containing excess desferrioxamine (DFX). The foxA(2)-disrupted single mutant grew poorly in the regular Fe-limited (0.2 microM) medium with 10 microM DFX, but grew well when the Fe level was raised to 1.0 microM with 10 microM DFX. For efficient acquisition of Fe-loaded ferrioxamine, N. europaea needs both ferrioxamine transporters FoxA(1) and FoxA(2). FoxA(1) probably regulates its own production, and it controls the production of FoxA(2) as well.

  16. Genome-wide transcriptional responses of Nitrosomonas europaea to zinc.

    PubMed

    Park, Sunhwa; Ely, Roger L

    2008-06-01

    Nitrosomonas europaea, a Gram-negative obligate chemolithoautotroph, participates in global nitrogen cycling by carrying out nitrification and derives energy for growth through oxidation of ammonia. In this work, the physiological, proteomic, and transcriptional responses of N. europaea to zinc stress were studied. The nitrite production rate and ammonia-dependent oxygen uptake rate of the cells exposed to 3.4 microM ZnCl2 decreased about 61 and 69% within 30 min, respectively. Two proteins were notably up regulated in zinc treatment and the mRNA levels of their encoding genes started to increase by 1 h after the addition of zinc. A total of 27 genes were up regulated and 30 genes were down regulated. Up-regulated genes included mercury resistance genes (merTPCAD), inorganic ion transport genes, oxidative stress genes, toxin-antitoxin genes, and two-component signal transduction systems genes. merTPCAD was the highest up-regulated operon (46-fold). Down-regulated genes included the RubisCO operon (cbbO), biosynthesis (mrsA), and amino acid transporter.

  17. A soluble form of ammonia monooxygenase in Nitrosomonas europaea.

    PubMed

    Gilch, Stefan; Meyer, Ortwin; Schmidt, Ingo

    2009-09-01

    Ammonia monooxygenase (AMO) of Nitrosomonas europaea is a metalloenzyme that catalyzes the oxidation of ammonia to hydroxylamine. This study shows that AMO resides in the cytoplasm of the bacteria in addition to its location in the membrane and is distributed approximately equally in both subcellular fractions. AMO in both fractions catalyzes the oxidation of ammonia and binds [(14)C]acetylene, a mechanism-based inhibitor which specifically interacts with catalytically active AMO. Soluble AMO was purified 12-fold to electrophoretic homogeneity with a yield of 8%. AMO has a molecular mass of approximately 283 kDa with subunits of ca. 27 kDa (alpha-subunit, AmoA), ca. 42 kDa (beta-subunit, AmoB), and ca. 24 kDa (gamma-subunit, cytochrome c(1)) in an alpha(3)beta(3)gamma(3) sub-unit structure. Different from the beta-subunit of membrane-bound AMO, AmoB of soluble AMO possesses an N-terminal signal sequence. AMO contains Cu (9.4+/-0.6 mol per mol AMO), Fe (3.9+/-0.3 mol per mol AMO), and Zn (0.5 to 2.6 mol per mol AMO). Upon reduction the visible absorption spectrum of AMO reveals absorption bands characteristic of cytochrome c. Electron para-magnetic resonance spectroscopy of air-oxidized AMO at 50 K shows a paramagnetic signal originating from Cu(2+) and at 10 K a paramagnetic signal characteristic of heme-Fe.

  18. Monochloramine cometabolism by Nitrosomonas europaea under drinking water conditions.

    PubMed

    Maestre, Juan P; Wahman, David G; Speitel, Gerald E

    2013-09-01

    Chloramine is widely used in United States drinking water systems as a secondary disinfectant, which may promote the growth of nitrifying bacteria because ammonia is present. At the onset of nitrification, both nitrifying bacteria and their products exert a monochloramine demand, decreasing the residual disinfectant concentration in water distribution systems. This work investigated another potentially significant mechanism for residual disinfectant loss: monochloramine cometabolism by ammonia-oxidizing bacteria (AOB). Monochloramine cometabolism was studied with the pure culture AOB Nitrosomonas europaea (ATCC 19718) in batch kinetic experiments under drinking water conditions. Three batch reactors were used in each experiment: a positive control to estimate the ammonia kinetic parameters, a negative control to account for abiotic reactions, and a cometabolism reactor to estimate the cometabolism kinetic constants. Kinetic parameters were estimated in AQUASIM with a simultaneous fit to all experimental data. The cometabolism reactors showed a more rapid monochloramine decay than in the negative controls, demonstrating that cometabolism occurs. Cometabolism kinetics were best described by a pseudo first order model with a reductant term to account for ammonia availability. Monochloramine cometabolism kinetics were similar to those of ammonia metabolism, and monochloramine cometabolism was a significant loss mechanism (30-60% of the observed monochloramine decay). These results suggest that monochloramine cometabolism should occur in practice and may be a significant contribution to monochloramine decay during nitrification episodes in drinking water distribution systems.

  19. Degradation of halogenated aliphatic compounds by the ammonia-oxidizing bacterium nitrosomonas europaea

    SciTech Connect

    Vannelli, T.; Logan, M.; Arciero, D.M.; Hooper, A.B. )

    1990-04-01

    Suspensions of Nitrosomonas europaea catalyzed the ammonia-stimulated aerobic transformation of the halogenated aliphatic compounds dichloromethane, dibromomethane, trichloromethane (chloroform), bromoethane, 1,2-dibromoethane (ethylene dibromide), 1,1,2-trichloroethane, 1,1,1-trichloroethane, monochloroethylene (vinyl chloride), gem-dichloroethylene, cis- and trans-dichloroethylene, cis-dibromoethylene, trichloroethylene, and 1,2,3-trichloropropane. Tetrachloromethane (carbon tetrachloride), tetrachloroethylene (perchloroethylene), and trans-dibromoethylene were not degraded.

  20. Degradation of halogenated aliphatic compounds by the ammonia-oxidizing bacterium Nitrosomonas europaea

    SciTech Connect

    Vannelli, T.; Logan, M.; Arciero, D.M.; Hooper, A.B.

    1990-01-01

    Suspensions of Nitrosomonas europaea catalyzed the ammonia-stimulated aerobic transformation of the halogenated aliphatic compounds dichloromethane, dibromomethane, trichloromethane (chloroform), bromoethane, 1,2-dibromoethane (ethylene dibromide), 1,1,2-trichloroethane, 1,1,1-trichloroethane, monochloroethylene (vinyl chloride), gem-dichloroethylene, cis- and trans-dichloroethylene, cis-dibromoethylene, trichloroethylene, and 1,2,3-trichloropropane. Tetrachloromethane (carbon tetrachloride), tetrachloroethylene (perchloroethylene), and trans-dibromoethylene were not degraded.

  1. Quantitative proteomic analysis of the chemolithoautotrophic bacterium Nitrosomonas europaea: comparison of growing- and energy-starved cells.

    PubMed

    Pellitteri-Hahn, Molly C; Halligan, Brian D; Scalf, Mark; Smith, Lloyd; Hickey, William J

    2011-04-01

    Obligately aerobic ammonia-oxidizing bacteria (AOB) like Nitrosomonas europaea play a pivotal role in the global nitrogen cycle. Although starvation tolerance is a key environmental adaptation, little is known about this response in AOB. The goal of these studies was to compare the composition of the N. europaea proteome in growing- and energy-starved cells using ¹⁵N labeling and HPLC-ESI-MS/MS. More than 6500 peptides were sequenced with high confidence, and matched to 876 proteins (34% of the protein coding genes). Of these, 126 proteins had two or more peptide forms identified by 10 or more scans, and were used in quantitative analysis and 27 were found to be significantly different in abundance between growing and starved cells. Proteins showing greater abundance in growing cells are geared toward biosynthesis, particularly DNA replication. Energy-starved cells were shifted away from biosynthesis and toward survival functions that included: cell envelope modification, protein protection/degradation, detoxification, and implementation of alternative energy generation mechanisms. Most of these activities have not previously been reported as associated with energy-starvation stress in N. europaea. This study provides insights into the potential effects of fluctuating environmental conditions on the regulation of physiological networks in N. europaea.

  2. Investigating Nitrosomonas europaea stress biomarkers in batch, continuous culture, and biofilm reactors.

    PubMed

    Radniecki, Tyler S; Lauchnor, Ellen G

    2011-01-01

    The understanding of nitrification inhibition in ammonia oxidizing bacteria (AOB) by priority pollutants and emerging contaminants is critical in managing the nitrogen cycle to preserve current water supplies, one of the National Academy of Engineers Grand Challenges in Engineering for the twenty-first century. Nitrosomonas europaea is an excellent model AOB for nitrification inhibition experimentation due to its well-defined NH(3) metabolism and the availability of a wide range of physiological and transcriptional tools that can characterize the mechanism of nitrification inhibition and probe N. europaea's response to the inhibitor. This chapter is a compilation of the physiological and transcriptional methods that have been used to characterize nitrification inhibition of N. europaea under a wide variety of growth conditions including batch, continuously cultured, and in biofilms. The protocols presented here can be applied to other AOB, and may be readily adapted for other autotrophic bacteria (e.g., nitrite oxidizing bacteria).

  3. Iron nutrition and physiological responses to iron stress in Nitrosomonas europaea.

    PubMed

    Wei, Xueming; Vajrala, Neeraja; Hauser, Loren; Sayavedra-Soto, Luis A; Arp, Daniel J

    2006-08-01

    Nitrosomonas europaea, as an ammonia-oxidizing bacterium, has a high Fe requirement and has 90 genes dedicated to Fe acquisition. Under Fe-limiting conditions (0.2 microM Fe), N. europaea was able to assimilate up to 70% of the available Fe in the medium even though it is unable to produce siderophores. Addition of exogenous siderophores to Fe-limited medium increased growth (final cell mass). Fe-limited cells had lower heme and cellular Fe contents, reduced membrane layers, and lower NH3- and NH2OH-dependent O2 consumption activities than Fe-replete cells. Fe acquisition-related proteins, such as a number of TonB-dependent Fe-siderophore receptors for ferrichrome and enterobactin and diffusion protein OmpC, were expressed to higher levels under Fe limitation, providing biochemical evidence for adaptation of N. europaea to Fe-limited conditions.

  4. DNA microarray mediated transcriptional profiling of Nitrosomonas europaea in response to linear alkylbenzene sulfonates.

    PubMed

    Urakawa, Hidetoshi; Matsumoto, Junpei; Inaba, Kazuho; Tsuneda, Satoshi

    2008-05-01

    Linear alkylbenzene sulfonates (LAS) constitute, quantitatively, the most important group of synthetic surfactants used today. We studied the gene expression of Nitrosomonas europaea in response to LAS using a DNA microarray because ammonia-oxidizers are thought to be more sensitive to LAS than other microorganisms. Our objective was to elucidate which genes are expressed for N. europaea in response to LAS exposure. Microarray analysis and real-time PCR assay revealed that c. 30 genes were significantly expressed after LAS exposure, in particular genes associated with energy production and conversion. Our findings demonstrate that physical disruption of membrane structures, which contain enzymes associated with energy production and conversion, might be an important explanation for the high sensitivity of N. europaea to LAS exposure.

  5. Cytotoxicity of sulfurous acid on cell membrane and bioactivity of Nitrosomonas europaea.

    PubMed

    Jiang, Ruiyu; Wang, Mingqing; Xue, Jianliang; Xu, Ning; Hou, Guihua; Zhang, Wubing

    2015-01-01

    Nitrosomonas europaea, an ammonia oxidizing bacterium, was chosen as a research model to study the alteration of cell membrane in the presence of sulfurous acid and biodegradation of acetochlor. Significant changes of the outer cell membrane were observed in the presence of sulfurous acid using scanning electron microscopy (SEM) and Atomic Force Microscopy (AFM). The fluorescence polarization has shown a significant decrease in membrane fluidity and the increase of permeability of cell membrane. Lysozyme experiment show the cell becomes easily influenced by substance in medium. Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) measurements show considerable amount of Ca(2+) and Mg(2+) in the supernatant from the sulfurous acid exposed cells. Sulfurous acid treatment enhanced the ability of N. europaea to degrade acetochlor. On this basis, it can be concluded that the increased cell permeability is favor for the absorbability of nutrition. As a result, N. europaea grows faster and the biodegradation efficiency was improved.

  6. Structural characterization of nitrosomonas europaea cytochrome c-552 variants with marked differences in electronic structure.

    PubMed

    Can, Mehmet; Krucinska, Jolanta; Zoppellaro, Giorgio; Andersen, Niels H; Wedekind, Joseph E; Hersleth, Hans-Petter; Andersson, K Kristoffer; Bren, Kara L

    2013-09-23

    Nitrosomonas europaea cytochrome c-552 (Ne c-552) variants with the same His/Met axial ligand set but with different EPR spectra have been characterized structurally, to aid understanding of how molecular structure determines heme electronic structure. Visible light absorption, Raman, and resonance Raman spectroscopy of the protein crystals was performed along with structure determination. The structures solved are those of Ne c-552, which displays a "HALS" (or highly anisotropic low-spin) EPR spectrum, and of the deletion mutant Ne N64Δ, which has a rhombic EPR spectrum. Two X-ray crystal structures of wild-type Ne c-552 are reported; one is of the protein isolated from N. europaea cells (Ne c-552n, 2.35 Å resolution), and the other is of recombinant protein expressed in Escherichia coli (Ne c-552r, 1.63 Å resolution). Ne N64Δ crystallized in two different space groups, and two structures are reported [monoclinic (2.1 Å resolution) and hexagonal (2.3 Å resolution)]. Comparison of the structures of the wild-type and mutant proteins reveals that heme ruffling is increased in the mutant; increased ruffling is predicted to yield a more rhombic EPR spectrum. The 2.35 Å Ne c-552n structure shows 18 molecules in the asymmetric unit; analysis of the structure is consistent with population of more than one axial Met configuration, as seen previously by NMR. Finally, the mutation was shown to yield a more hydrophobic heme pocket and to expel water molecules from near the axial Met. These structures reveal that heme pocket residue 64 plays multiple roles in regulating the axial ligand orientation and the interaction of water with the heme. These results support the hypothesis that more ruffled hemes lead to more rhombic EPR signals in cytochromes c with His/Met axial ligation.

  7. Cometabolism of Monochloramine by Nitrosomonas europaea under Distribution System Conditions

    EPA Science Inventory

    Batch kinetic experiments were carried out with a pure culture of N. europaea to characterize the kinetics of NH2Cl cometabolism. Nitrite, nitrate, NH2Cl, ammonia and pH were measured. The experiments were performed at a variety of conditions relevant to distribution system nitri...

  8. Nitrosomonas europaea cytochrome P460 is a direct link between nitrification and nitrous oxide emission.

    PubMed

    Caranto, Jonathan D; Vilbert, Avery C; Lancaster, Kyle M

    2016-12-20

    Ammonia oxidizing bacteria (AOB) are major contributors to the emission of nitrous oxide (N2O). It has been proposed that N2O is produced by reduction of NO. Here, we report that the enzyme cytochrome (cyt) P460 from the AOB Nitrosomonas europaea converts hydroxylamine (NH2OH) quantitatively to N2O under anaerobic conditions. Previous literature reported that this enzyme oxidizes NH2OH to nitrite ([Formula: see text]) under aerobic conditions. Although we observe [Formula: see text] formation under aerobic conditions, its concentration is not stoichiometric with the NH2OH concentration. By contrast, under anaerobic conditions, the enzyme uses 4 oxidizing equivalents (eq) to convert 2 eq of NH2OH to N2O. Enzyme kinetics coupled to UV/visible absorption and electron paramagnetic resonance (EPR) spectroscopies support a mechanism in which an Fe(III)-NH2OH adduct of cyt P460 is oxidized to an {FeNO}(6) unit. This species subsequently undergoes nucleophilic attack by a second equivalent of NH2OH, forming the N-N bond of N2O during a bimolecular, rate-determining step. We propose that [Formula: see text] results when nitric oxide (NO) dissociates from the {FeNO}(6) intermediate and reacts with dioxygen. Thus, [Formula: see text] is not a direct product of cyt P460 activity. We hypothesize that the cyt P460 oxidation of NH2OH contributes to NO and N2O emissions from nitrifying microorganisms.

  9. Interactions of Nitrosomonas europaea and Nitrobacter winogradskyi grown in co-culture.

    PubMed

    Pérez, José; Buchanan, Alex; Mellbye, Brett; Ferrell, Rebecca; Chang, Jeffrey H; Chaplen, Frank; Bottomley, Peter J; Arp, Daniel J; Sayavedra-Soto, Luis A

    2015-01-01

    Nitrosomonas europaea and Nitrobacter winogradskyi were grown singly and in co-culture in chemostats to probe for physiological differences between the two growth conditions. Co-culture growth medium containing 60 mM NH4 (+) resulted in a cell density (0.20-0.29 OD600) greater than the sum of the densities in single chemostat cultures, i.e., 0.09-0.14 OD600 for N. europaea with 60 mM NH4 (+)and 0.04-0.06 OD600 for N. winogradskyi with 60 mM NO2 (-). The NO2 (-)- and NH4 (+)-dependent O2 uptake rates, qRT-PCR, and microscopic observations indicated that in co-culture, N. europaea contributed ~0.20 OD600 (~80 %) and N. winogradskyi ~0.05 OD600 (~20 %). In co-culture, the transcriptomes showed that the mRNA levels of 773 genes in N. europaea (30.2 % of the genes) and of 372 genes in N. winogradskyi (11.8 % of the genes) changed significantly. Total cell growth and the analysis of the transcriptome revealed that in co-culture, N. europaea benefits more than N. winogradskyi.

  10. Functional and physiological evidence for a rhesus-type ammonia transporter in Nitrosomonas europaea.

    PubMed

    Weidinger, Kerstin; Neuhäuser, Benjamin; Gilch, Stefan; Ludewig, Uwe; Meyer, Ortwin; Schmidt, Ingo

    2007-08-01

    Ammonium transporters form a conserved family of transport proteins and are widely distributed among all domains of life. The genome of Nitrosomonas europaea codes for a single gene (rh1) that belongs to the family of the AMT/Rh ammonium transporters. For the first time, this study provides functional and physiological evidence for a rhesus-type ammonia transporter in bacteria (N. europaea). The methylammonium (MA) transport activity of N. europaea correlated with the Rh1 expression. The K(m) value for the MA uptake of N. europaea was 1.8+/-0.2 mM (pH 7.25), and the uptake was competitively inhibited by ammonium [K(i)(NH(4) (+)) 0.3+/-0.1 mM at pH 7.25]. The MA uptake rate was pH dependent, indicating that the uncharged form of MA is transported by Rh1. An effect of the glutamine synthetase on the MA uptake was not observed. When expressed in Saccharomyces cerevisiae, the function of Rh1 from N. europaea as an ammonia/MA transporter was confirmed. The results suggest that Rh1 equilibrates the uncharged substrate species. A low pH value in the periplasmic space during ammonia oxidation seems to be responsible for the ammonium accumulation functioning as an acid NH(4) (+) trap.

  11. Complete genome sequence of the ammonia-oxidizing bacterium and obligate chemolithoautotroph Nitrosomonas europaea.

    PubMed

    Chain, Patrick; Lamerdin, Jane; Larimer, Frank; Regala, Warren; Lao, Victoria; Land, Miriam; Hauser, Loren; Hooper, Alan; Klotz, Martin; Norton, Jeanette; Sayavedra-Soto, Luis; Arciero, Dave; Hommes, Norman; Whittaker, Mark; Arp, Daniel

    2003-05-01

    Nitrosomonas europaea (ATCC 19718) is a gram-negative obligate chemolithoautotroph that can derive all its energy and reductant for growth from the oxidation of ammonia to nitrite. Nitrosomonas europaea participates in the biogeochemical N cycle in the process of nitrification. Its genome consists of a single circular chromosome of 2,812,094 bp. The GC skew analysis indicates that the genome is divided into two unequal replichores. Genes are distributed evenly around the genome, with approximately 47% transcribed from one strand and approximately 53% transcribed from the complementary strand. A total of 2,460 protein-encoding genes emerged from the modeling effort, averaging 1,011 bp in length, with intergenic regions averaging 117 bp. Genes necessary for the catabolism of ammonia, energy and reductant generation, biosynthesis, and CO(2) and NH(3) assimilation were identified. In contrast, genes for catabolism of organic compounds are limited. Genes encoding transporters for inorganic ions were plentiful, whereas genes encoding transporters for organic molecules were scant. Complex repetitive elements constitute ca. 5% of the genome. Among these are 85 predicted insertion sequence elements in eight different families. The strategy of N. europaea to accumulate Fe from the environment involves several classes of Fe receptors with more than 20 genes devoted to these receptors. However, genes for the synthesis of only one siderophore, citrate, were identified in the genome. This genome has provided new insights into the growth and metabolism of ammonia-oxidizing bacteria.

  12. Biotreatment of ammonia in air by an immobilized Nitrosomonas europaea biofilter

    SciTech Connect

    Chung, Y.C.; Huang, C.

    1998-09-01

    The chemoautotrophic microorganism Nitrosomonas europaea has been utilized to remove gaseous ammonia in a continuous reactor. Extensive tests including removal characteristics, metabolic products, and removal efficiencies of ammonia by N. europaea were conducted. The operational principles governing the biofilter and the question of the heterotroph contamination were also studied. The optimum pH value and operating temperature required to effectively remove ammonia were found to be pH 7.5 and 30 C, respectively. When the diluted inlet ammonia concentration was 10 or 20 ppm, the biofilter achieved a 99% removal efficiency after 4 days of operation. However, higher ammonia inlet concentrations and heterotroph contamination resulted in a lower removal efficiency. The results showed that the maximum removal rate and apparent saturation constant were 1.11 g-N/day/kg-bead and 63.67 ppm, respectively. The mainly metabolic product of ammonia oxidation was determined to be nitrite, but the conversion ratio was dependent on whether the contaminations by heterotrophic bacteria were present. From an operating perspective, if the ammonia emission limit (i.e., 1 ppm) was to be achieved, the maximum inlet concentration could not exceed 75 ppm. These results suggest that the immobilized Nitrosomonas europaea biofilter provides a significant potential for treating ammonia in the gaseous phase.

  13. Factors limiting aliphatic chlorocarbon degradation by Nitrosomonas europaea: Cometabolic inactivation of ammonia monooxygenase and substrate specificity

    SciTech Connect

    Rasche, M.E.; Hyman, M.R.; Arp, D.J. )

    1991-10-01

    The soil nitrifying bacterium Nitrosomonas europaea is capable of degrading trichloroethylene (TCE) and other halogenated hydrocarbons. TCE cometabolism by N. europaea resulted in an irreversible loss of TCE biodegradative capacity, ammonia-oxidizing activity, and ammonia-dependent O{sub 2} uptake by the cells. Inactivation was not observed in the presence of allylthiourea, a specific inhibitor of enzyme ammonia monooxygenase, or under anaerobic conditions, indicating that the TCE-mediated inactivation required ammonia monooxygenase activity. When N. europaea cells were incubated with ({sup 14}C)TCE under conditions which allowed turnover of ammonia monooxygenase, a number of cellular proteins were covalently labeled with {sup 14}C. Treatment of cells with allylthiourea or acetylene prior to incubation with ({sup 14}C)TCE prevented incorporation of {sup 14}C into proteins. The ammonia-oxidizing activity of cells inactivated in the presence of TCE could be recovered through a process requiring de novo protein synthesis. In addition to TCE, a series of chlorinated methanes, ethanes, and other ethylenes were screened as substrates for ammonia monooxygenase and for their ability to inactivate the ammonia-oxidizing system of N. europaea. The chlorocarbons would be divided into three classes depending on their biodegradability and inactivating potential: (1) compounds which were not biodegradable by N. europaea and which had no toxic effect on the cells (2) compounds which were cooxidized by N. europaea and had little or no toxic effect on the cells; and (3) compounds which were cooxidized and produced a turnover-dependent inactivation of ammonia oxidation by N. europaea.

  14. Nitrogen isotopomer site preference of N2O produced by Nitrosomonas europaea and Methylococcus capsulatus Bath.

    PubMed

    Sutka, R L; Ostrom, N E; Ostrom, P H; Gandhi, H; Breznak, J A

    2003-01-01

    The relative importance of individual microbial pathways in nitrous oxide (N(2)O) production is not well known. The intramolecular distribution of (15)N in N(2)O provides a basis for distinguishing biological pathways. Concentrated cell suspensions of Methylococcus capsulatus Bath and Nitrosomonas europaea were used to investigate the site preference of N(2)O by microbial processes during nitrification. The average site preference of N(2)O formed during hydroxylamine oxidation by M. capsulatus Bath (5.5 +/- 3.5 per thousand) and N. europaea (-2.3 +/- 1.9 per thousand) and nitrite reduction by N. europaea (-8.3 +/- 3.6 per thousand) differed significantly (ANOVA, f((2,35)) = 247.9, p = 0). These results demonstrate that the mechanisms for hydroxylamine oxidation are distinct in M. capsulatus Bath and N. europaea. The average delta(18)O-N(2)O values of N(2)O formed during hydroxylamine oxidation for M. capsulatus Bath (53.1 +/- 2.9 per thousand) and N. europaea (-23.4 +/- 7.2 per thousand) and nitrite reduction by N. europaea (4.6 +/- 1.4 per thousand) were significantly different (ANOVA, f((2,35)) = 279.98, p = 0). Although the nitrogen isotope value of the substrate, hydroxylamine, was similar in both cultures, the observed fractionation (delta(15)N) associated with N(2)O production via hydroxylamine oxidation by M. capsulatus Bath and N. europaea (-2.3 and 26.0 per thousand, respectively) provided evidence that differences in isotopic fractionation were associated with these two organisms. The site preferences in this study are the first measured values for isolated microbial processes. The differences in site preference are significant and indicate that isotopomers provide a basis for apportioning biological processes producing N(2)O.

  15. Methane oxidation by Nitrosococcus oceanus and Nitrosomonas europaea

    SciTech Connect

    Jones, R.D.; Morita, R.Y.

    1983-02-01

    Chemolithotrophic ammonium-oxidizing bacteria were examined as to their ability to oxidize methane in the absence of ammonium or nitrite. The addition of ammonium stimulated both CO/sub 2/ production and cellular incorporation of methane-carbon by N. oceanus and N. europaea. Less than 0.1 mM CH/sub 4/ in solution inhibited the oxidation of ammonium by N. oceanus by 87% but had no inhibitory effects on N. europaea. In the absence of NH/sub 4/-N, N. oceanus achieved a maximum methane oxidation rate of 2.20 x 10/sup -2/ ..mu..mol of CH/sub 4/ h/sup -1/ mg (dry weight) of cells/sup -1/, which remained constant as the methane concentration was increased. In the presence of NH/sub 4/-N (10 ppm (10 ..mu..g/ml)), its maximum rate was 26.4 x 10/sup -2/ ..mu..mol of CH/sub 4/ h/sup -1/ mg (dry weight) of cells/sup -1/ at a methane concentration of 1.19 x 10/sup -1/ mM. Increasing the methane concentrations above this level decreased CO/sub 2/ production, whereas cellular incorporation of methane-carbon continued to increase. N. europaea showed a linear response throughout the test range, with an activity of 196.0 x 10/sup -2/ ..mu..mol of CH/sub 4/ h/sup -1/ mg (dry weight) of cells/sup -1/ at a methane concentration of 1.38 x 10/sup -1/ mM. Both nitrite and nitrate stimulated the oxidation of methane. The pH range was similar to that for ammonium oxidation, but the points of maximum activity were at lower values for the oxidation of methane. (JMT)

  16. Interaction of the mechanism-based inactivator acetylene with ammonia monooxygenase of Nitrosomonas europaea.

    PubMed

    Gilch, Stefan; Vogel, Manja; Lorenz, Matthias W; Meyer, Ortwin; Schmidt, Ingo

    2009-01-01

    The ammonia monooxygenase (AMO) of Nitrosomonas europaea is a metalloenzyme that catalyses the oxidation of ammonia to hydroxylamine. We have identified histidine 191 of AmoA as the binding site for the oxidized mechanism-based inactivator acetylene. Binding of acetylene changed the molecular mass of His-191 from 155.15 to 197.2 Da (+42.05), providing evidence that acetylene was oxidized to ketene (CH2CO; 42.04 Da) which binds specifically to His-191. It must be assumed that His-191 is part of the acetylene-activating site in AMO or at least directly neighbours this site.

  17. Computational prediction and transcriptional analysis of sRNAs in Nitrosomonas europaea.

    PubMed

    Gvakharia, Barbara O; Tjaden, Brian; Vajrala, Neeraja; Sayavedra-Soto, Luis A; Arp, Daniel J

    2010-11-01

    Bacterial small noncoding RNAs (sRNAs) have been discovered in many genetically well-studied microorganisms and have been shown to regulate critical cellular processes at the post-transcriptional level. In this study, we used comparative genomics and microarray data to analyze the genome of the ammonia-oxidizing bacterium Nitrosomonas europaea for the presence and expression of sRNAs. Fifteen genes encoding putative sRNAs (psRNAs) were identified. Most of these genes showed altered expression in a variety of experimental conditions. The transcripts of two psRNAs were further characterized by mapping their 5'- and 3'-ends and by real-time PCR. The results of these analyses suggested that one of them, psRNA11, is involved in iron homeostasis in N. europaea.

  18. AAU-Specific RNA Cleavage Mediated by MazF Toxin Endoribonuclease Conserved in Nitrosomonas europaea

    PubMed Central

    Miyamoto, Tatsuki; Yokota, Akiko; Tsuneda, Satoshi; Noda, Naohiro

    2016-01-01

    Nitrosomonas europaea carries numerous toxin-antitoxin systems. However, despite the abundant representation in its chromosome, studies have not surveyed the underlying molecular functions in detail, and their biological roles remain enigmatic. In the present study, we found that a chromosomally-encoded MazF family member, predicted at the locus NE1181, is a functional toxin endoribonuclease, and constitutes a toxin-antitoxin system, together with its cognate antitoxin, MazE. Massive parallel sequencing provided strong evidence that this toxin endoribonuclease exhibits RNA cleavage activity, primarily against the AAU triplet. This sequence-specificity was supported by the results of fluorometric assays. Our results indicate that N. europaea alters the translation profile and regulates its growth using the MazF family of endoribonuclease under certain stressful conditions. PMID:27271670

  19. AAU-Specific RNA Cleavage Mediated by MazF Toxin Endoribonuclease Conserved in Nitrosomonas europaea.

    PubMed

    Miyamoto, Tatsuki; Yokota, Akiko; Tsuneda, Satoshi; Noda, Naohiro

    2016-06-04

    Nitrosomonas europaea carries numerous toxin-antitoxin systems. However, despite the abundant representation in its chromosome, studies have not surveyed the underlying molecular functions in detail, and their biological roles remain enigmatic. In the present study, we found that a chromosomally-encoded MazF family member, predicted at the locus NE1181, is a functional toxin endoribonuclease, and constitutes a toxin-antitoxin system, together with its cognate antitoxin, MazE. Massive parallel sequencing provided strong evidence that this toxin endoribonuclease exhibits RNA cleavage activity, primarily against the AAU triplet. This sequence-specificity was supported by the results of fluorometric assays. Our results indicate that N. europaea alters the translation profile and regulates its growth using the MazF family of endoribonuclease under certain stressful conditions.

  20. Physiological and transcriptional responses of Nitrosomonas europaea to toluene and benzene inhibition.

    PubMed

    Radniecki, Tyler S; Dolan, Mark E; Semprini, Lewis

    2008-06-01

    Ammonia oxidizing bacteria (AOB) are inhibited by many compounds found in wastewater treatment plant (WWTP) influent, including aromatic hydrocarbons. The detection of "sentinel genes" to identify the presence of aromatic hydrocarbons could be useful to WWTP operators. In this study, the transcriptomic responses of Nitrosomonas europaea during the cometabolism of benzene to phenol and toluene to benzyl alcohol and benzaldehyde were evaluated using whole genome Affymetrix microarrays and qRT-PCR. Benzyl alcohol and benzaldehyde were found not to inhibit N. europaea. However, phenol concentrations as low as 5 microM directly inhibited ammonia oxidation. Surprisingly, there were no significant up- or down-regulation of genes in N. europaea cells exposed to 20 microM toluene, which caused 50% inhibition of ammonia oxidation. Exposing N. europaea to 40 microM benzene, which caused a similar degree of inhibition, resulted in the up-regulation of seven adjacent genes, including NE 1545 (a putative pirin protein) and NE 1546 (a putative membrane protein), that appear to be involved with fatty-acid metabolism, lipid biosynthesis, and membrane protein synthesis. qRT-PCR analysis revealed that NE 1545 and NE 1546 were significantly up-regulated upon exposure to benzene and phenol, but not upon exposure to toluene. Transmission electron microscope images revealed a shift in outer cell structure in response to benzene exposure.

  1. Inactivation of Nitrosomonas europaea and pathogenic Escherichia coli by chlorine and monochloramine.

    PubMed

    Chauret, Christian; Smith, Curtis; Baribeau, Hélène

    2008-09-01

    The purpose of this study was to measure the chlorine and monochloramine inactivation kinetics of Nitrosomonas europaea at 21 degrees C in the presence and absence of particles. The inactivation kinetics rates were compared with those obtained with Escherichia coli O157:H7. The results show that, in pure water, the use of free chlorine produced 4 log10 of N. europaea inactivation at a CT value of 0.8 mg.min l(-1), whereas monochloramine yielded 4 log10 of inactivation at CT values of approximately 9.9-16.4mg.min l(-1). With E. coli, chlorine produced approximately 4 1og10 of inactivation at a CT of 0.13 mg.min l(-1), whereas monochloramine resulted in 4 logo10 of inactivation at a CT of approximately 9.2 mg.min l(-1). These results suggest that N. europaea is more resistant to monochloramine and chlorine than E. coli. Corrosion debris, soil material and wastewater had no statistically significant (p < 0.05) impact on the inactivation of N. europaea by either chlorine or monochloramine. It seems likely that the CT values present in distribution systems would be sufficient to control suspended cells of these two organisms, especially under conditions of breakpoint chlorination, which could be used to control nitrification. Adequate disinfection should prevent the growth of these organisms in a distribution system.

  2. Inhibition, Inactivation, and Recovery of Ammonia-Oxidizing Activity in Cometabolism of Trichloroethylene by Nitrosomonas europaea

    PubMed Central

    Hyman, M. R.; Russell, S. A.; Ely, R. L.; Williamson, K. J.; Arp, D. J.

    1995-01-01

    The kinetics of the cometabolism of trichloroethylene (TCE) by the ammonia-oxidizing soil bacterium Nitrosomonas europaea in short-term (<10-min) incubations were investigated. Three individual effects of TCE cometabolism on this bacterium were characterized. First, we observed that TCE is a potent competitive inhibitor of ammonia oxidation by N. europaea. The K(infi) value for TCE (30 (mu)M) is similar to the K(infm) for ammonia (40 (mu)M). Second, we examined the toxicity associated with TCE cometabolism by N. europaea. Stationary-phase cells of N. europaea oxidized approximately 60 nmol of TCE per mg of protein before ammonia-oxidizing activity was completely inactivated by reactive intermediates generated during TCE oxidation. At the TCE concentrations used in these experiments, ammonia did not provide significant protection against inactivation. Third, we have determined the ability of cells to recover ammonia-oxidizing activity after exposure to TCE. Cells recovering from TCE inactivation were compared with cells recovering from the specific inactivation of ammonia-oxidizing activity by light. The recovery kinetics were indistinguishable when 40% or less of the activity was inactivated. However, at increased levels of inactivation, TCE-inactivated cells did not recover as rapidly as light-inactivated cells. The kinetics of recovery appear to be dependent on both the extent of inactivation of ammonia-oxidizing activity and the degree of specificity of the inactivating treatment. PMID:16534997

  3. Respiration-dependent proton translocation in Nitrosomonas europaea and its apparent absence in Nitrobacter agilis during inorganic oxidations.

    PubMed Central

    Hollocher, T C; Kumar, S; Nicholas, D J

    1982-01-01

    Oxygen pulse experiments were carried out with the nitrifying bacteria Nitrosomonas europaea and Nitrobacter agilis and with spheroplasts and everted vesicles prepared from Nitrobacter agilis. In addition to thiocyanate, the salting-in anions perchlorate and trichloroacetate proved to be permeant and effective in allowing respiration-dependent proton translocation with Nitrosomonas europaea. Valinomycin-K+, however, was generally ineffective in this respect with Nitrosomonas europaea. The observed leads to H+/O ratio for ammonium ion oxidation by Nitrosomonas europaea was 3.4; that for hydroxylamine and hydrazine cation oxidation was 4.4. These values, when corrected for production of stoichiometric protons and for the fact that the first step in ammonium ion oxidation (hydroxylamine production) is mediated by a monooxygenase, give effective leads to H+/O ratios of about 4 for these three substrates. This value compares favorably with those obtained with other aerobes. No convincing evidence was obtained for operation of a respiratory proton pump in Nitrobacter agilis during nitrite oxidation. Implications of this unexpected result are discussed. PMID:6277846

  4. Monochloramine disinfection kinetics of Nitrosomonas europaea by propidium monoazide quantitative PCR and Live/Dead BacLight Methods

    EPA Science Inventory

    Monochloramine disinfection kinetics were determined for the pure culture ammonia-oxidizing bacterium Nitrosomonas europaea (ATCC 19718) by two culture independent methods: (1) LIVE/DEAD® BacLight™ (LD) and (2) propidium monoazide quantitative PCR (PMA-qPCR). Both methods were f...

  5. Role of nitrite reductase in the ammonia-oxidizing pathway of Nitrosomonas europaea.

    PubMed

    Cantera, J Jason L; Stein, Lisa Y

    2007-10-01

    Metabolism of ammonia (NH(3)) and hydroxylamine (NH(2)OH) by wild-type and a nitrite reductase (nirK) deficient mutant of Nitrosomonas europaea was investigated to clarify the role of NirK in the NH(3) oxidation pathway. NirK-deficient N. europaea grew more slowly, consumed less NH(3), had a lower rate of nitrite (NO(2) (-)) production, and a significantly higher rate of nitrous oxide (N(2)O) production than the wild-type when incubated with NH(3) under high O(2) tension. In incubations with NH(3) under low O(2) tension, NirK-deficient N. europaea grew more slowly, but had only modest differences in NH(3) oxidation and product formation rates relative to the wild-type. In contrast, the nirK mutant oxidized NH(2)OH to NO(2) (-) at consistently slower rates than the wild-type, especially under low O(2) tension, and lost a significant pool of NH(2)OH-N to products other than NO(2) (-) and N(2)O. The rate of N(2)O production by the nirK mutant was ca. three times higher than the wild-type during hydrazine-dependent NO(2) (-) reduction under both high and low O(2) tension. Together, the results indicate that NirK activity supports growth of N. europaea by supporting the oxidation of NH(3) to NO(2) (-) via NH(2)OH, and stimulation of hydrazine-dependent NO(2) (-) reduction by NirK-deficient N. europaea indicated the presence of an alternative, enzymatic pathway for N(2)O production.

  6. Hydroxylamine addition impact to Nitrosomonas europaea activity in the presence of monochloramine.

    PubMed

    Wahman, David G; Speitel, Gerald E

    2015-01-01

    In drinking water, monochloramine may promote ammonia–oxidizing bacteria (AOB) growth because of concurrent ammonia presence. AOB use (i) ammonia monooxygenase for biological ammonia oxidation to hydroxylamine and (ii) hydroxylamine oxidoreductase for biological hydroxylamine oxidation to nitrite. In addition, monochloramine and hydroxylamine abiotically react, providing AOB a potential benefit by removing the disinfectant (monochloramine) and releasing growth substrate (ammonia). Alternatively and because biological hydroxylamine oxidation supplies the electrons (reductant) required for biological ammonia oxidation, the monochloramine/hydroxylamine abiotic reaction represents a possible inactivation mechanism by consuming hydroxylamine and inhibiting reductant generation. To investigate the abiotic monochloramine and hydroxylamine reaction's impact on AOB activity, the current study used batch experiments with Nitrosomonas europaea (AOB pure culture), ammonia, monochloramine, and hydroxylamine addition. To decipher whether hydroxylamine addition benefitted N. europaea activity by (i) removing monochloramine and releasing free ammonia or (ii) providing an additional effect (possibly the aforementioned reductant source), a previously developed cometabolism model was coupled with an abiotic monochloramine and hydroxylamine model for data interpretation. N. europaea maintained ammonia oxidizing activity when hydroxylamine was added before complete ammonia oxidation cessation. The impact could not be accounted for by monochloramine removal and free ammonia release alone and was concentration dependent for both monochloramine and hydroxylamine. In addition, a preferential negative impact occurred for ammonia versus hydroxylamine oxidation. These results suggest an additional benefit of exogenous hydroxylamine addition beyond monochloramine removal and free ammonia release, possibly providing reductant generation.

  7. Copper toxicity to bioluminescent Nitrosomonas europaea in soil is explained by the free metal ion activity in pore water.

    PubMed

    Ore, S; Mertens, J; Brandt, K K; Smolders, E

    2010-12-01

    The terrestrial biotic ligand model (BLM) for metal toxicity in soil postulates that metal toxicity depends on the free metal ion activity in solution and on ions competing for metal sorption to the biotic ligand. Unequivocal evidence for the BLM assumptions is most difficult to obtain for native soil microorganisms because the abiotic and biotic compartments cannot be experimentally separated. Here, we report copper (Cu) toxicity to a bioluminescent Nitrosomonas europaea reporter strain that was used in a solid phase-contact assay and in corresponding soil extracts and artificial soil solutions. The Cu(2+) ion activities that halve bioluminescence (EC50) in artificial solutions ranged 10(-5) to 10(-7) M and increased with increasing activities of H(+), Ca(2+) and Mg(2+) according to the BLM concept. The solution based Cu(2+) EC50 values of N. europaea in six contaminated soils ranged 2 × 10(-6) to 2 × 10(-9) M and these thresholds for both solid phase or soil extract based assays were well predicted by the ion competition model fitted to artificial solution data. In addition, solution based Cu(2+) EC50 of the solid phase-contact assay were never smaller than corresponding values in soil extracts suggesting no additional solid phase toxic route. By restricting the analysis to the same added species, we show that the Cu(2+) in solution represents the toxic species to this bacterium.

  8. MELiSSA third compartment: Nitrosomonas europaea and Nitrobacter winogradskyi axenic cultures in bioreactors

    NASA Astrophysics Data System (ADS)

    Cruvellier, Nelly; Lasseur, Christophe; Poughon, Laurent; Creuly, Catherine; Dussap, Gilles

    Nitrogen is a key element for the life and its balance on Earth is regulated by the nitrogen cycle. This loop includes several steps among which nitrification that permits the transformation of the ammonium into nitrate. The MELiSSA loop is an artificial ecosystem designed for life support systems (LSS). It is based on the carbon and nitrogen cycles and the recycling of the non-edible part of the higher plants and the waste produced by the crew. In this order, all the wastes are collected in the first compartment to degrade them into organic acids and CO2. These compounds are joining the second compartment which is a photoheterotrophic compartment where at the outlet an organic-free medium containing ammonium is produced. This solution will be the substrate of the third compartment where nitrification is done. This compartment has to oxidize the ammonium into nitrate, and this biological reaction needs two steps. In the MELiSSA loop, the nitrification is carried out by two bacteria: Nitrosomonas europaea ATCC® 19718™ which is oxidizing ammonia into nitrite and Nitrobacter winogradskyi ATCC® 25391™ which is producing nitrate from nitrite in the third compartment. These two bacteria are growing in axenic conditions on a fixed bed bioreactor filled with Biostyr® beads. The nitrogen compounds are controlled by Ionic Chromatography and colorimetric titration for each sample. The work presented here deals with the culture of both bacteria in pure cultures and mixed cultures in stirred and aerated bioreactors of different volumes. The first aim of our work is the characterization of the bacteria growth in bioreactors and in the nitrifying fixed-bed column. The experimental results confirm that the growth is slow; the maximal growth rate in suspended cultures is 0.054h-1 for Nitrosomonas europaea and 0.022h-1 for Nitrobacter winogradskyi. Mixed cultures are difficult to control and operate but one could be done for more than 500 hours. The characterization of the

  9. Influence of liberated silver from silver nanoparticles on nitrification inhibition of Nitrosomonas europaea.

    PubMed

    Radniecki, Tyler S; Stankus, Dylan P; Neigh, Arianne; Nason, Jeffrey A; Semprini, Lewis

    2011-09-01

    The ecotoxicity of silver nanoparticles (Ag-NPs) to wastewater biota, including ammonia oxidizing bacteria (AOB), is gaining increasing interest as the number of products containing Ag-NPs continues to rise exponentially and they are expected to accumulate in wastewater treatment plants. This research demonstrated that the addition order of Ag-NP and the media constituents had a profound influence on the stability of the Ag-NP suspension and the corresponding repeatability of results and sensitivity of Nitrosomonas europaea. N. europaea, a model AOB, was found to be extremely sensitive to ionic silver (Ag(+)) and two sizes of Ag-NPs (20 and 80 nm). Ag(+) exposures resulted in the highest level of toxicity with smaller Ag-NPs (20 nm) being more toxic than larger Ag-NPs (80 nm). The increased sensitivity of N. europaea to smaller Ag-NPs was caused by their higher rates of dissolved silver (dAg) release, via dissolution, due to a greater surface area to volume ratio. dAg was shown to be responsible for the vast majority of the observed Ag-NP toxicity, as determined by abiotic Ag-NP dissolution tests. For the sizes of Ag-NP studied (20 and 80 nm), there appears to be a negligible nanoparticle-specific toxicity. This was further supported by similarities in inhibition mechanisms between Ag(+) and Ag-NP, with both causing decreases in AMO activity and destabilization of the outer-membrane of N. europaea. Finally, equal concentrations of total silver were found to be tightly associated to both Ag(+) and Ag-NP-exposed cells despite Ag-NP concentrations being five times greater, by mass, than Ag(+) concentrations.

  10. Influence of Water Hardness on Silver Ion and Silver Nanoparticle Fate and Toxicity Toward Nitrosomonas europaea.

    PubMed

    Anderson, Joseph W; Semprini, Lewis; Radniecki, Tyler S

    2014-07-01

    This study investigated the influence of water hardness (Mg(2+) and Ca(2+)) on the fate and toxicity of 20 nm citrate silver nanoparticles (AgNPs) and Ag(+) toward Nitrosomonas europaea, a model ammonia-oxidizing bacterium. Nitrification inhibition of N. europaea by 1 ppm AgNPs and 0.5 ppm Ag(+) was reduced from 80% and 83%, respectively, in the absence of Mg(2+) to 2% and 33%, respectively, in the presence of 730 μM Mg(2+). Introduction of Mg(2+) resulted in the rapid aggregation of the AgNP suspensions and reduced the 3 h Ag(+) dissolution rates from 30%, in the absence of Mg(2+), to 9%, in the presence of 730 μM Mg(2+). Reduced AgNP dissolution rates resulted in decreased concentrations of silver that were found adsorbed to N. europaea cells. Increasing AgNP concentrations in the presence of Mg(2+) increased the observed inhibition of nitrification, but was always less than what was observed in the absence of Mg(2+). The presence of Mg(2+) also reduced the adsorption of Ag(+) to cells, possibly due to multiple mechanisms, including a reduction in the negative surface charge of the N. europaea membrane and a competition between Mg(2+) and Ag(+) for membrane binding sites and transport into the cells. Ca(2+) demonstrated similar protection mechanisms, as Ag(+) toxicity was reduced and AgNP suspensions aggregated and decreased their dissolution rates. These results indicate that the toxicity of Ag(+) and AgNPs to nitrifying bacteria in wastewater treatment would be less pronounced in systems with hard water.

  11. Inhibition and gene expression of Nitrosomonas europaea biofilms exposed to phenol and toluene.

    PubMed

    Lauchnor, Ellen G; Radniecki, Tyler S; Semprini, Lewis

    2011-04-01

    Pure culture biofilms of the ammonia-oxidizing bacterium Nitrosomonas europaea were grown in a Drip Flow Biofilm Reactor and exposed to the aromatic hydrocarbons phenol and toluene. Ammonia oxidation rates, as measured by nitrite production in the biofilms, were inhibited 50% when exposed to 56 µM phenol or 100 µM toluene, while 50% inhibition of suspended cells occurred at 8 µM phenol or 20 µM toluene. Biofilm-grown cells dispersed into liquid medium and immediately exposed to phenol or toluene experienced similar inhibition levels as batch grown cells, indicating that mass transfer may be a factor in N. europaea biofilm resistance. Whole genome microarray analysis of gene expression was used to detect genes up-regulated in biofilms during toluene and phenol exposure. Two genes, a putative pirin protein (NE1545) and a putative inner membrane protein (NE1546) were up-regulated during phenol exposure, but no genes were up-regulated during toluene exposure. Using qRT-PCR, up-regulation of NE1545 was detected in biofilms and suspended cells exposed to a range of phenol concentrations and levels of inhibition. In the biofilms, NE1545 expression was up-regulated an average of 13-fold over the range of phenol concentrations tested, and was essentially independent of phenol concentration. However, the expression of NE1545 in suspended cells increased from 20-fold at 7 µM phenol up to 80-fold at 30 µM phenol. This study demonstrates that biofilms of N. europaea are more resistant than suspended cells to inhibition of ammonia oxidation by phenol and toluene, even though the global transcriptional responses to the inhibitors do not differ in N. europaea between the suspended and attached growth states.

  12. Global metabolomic responses of Nitrosomonas europaea 19718 to cold stress and altered ammonia feeding patterns.

    PubMed

    Lu, Huijie; Ulanov, Alexander V; Nobu, Masaru; Liu, Wen-Tso

    2016-02-01

    The model ammonia-oxidizing bacterium Nitrosomonas europaea represents one of the environmentally and biotechnologically significant microorganisms. Genome-based studies over the last decade have led to many intriguing discoveries about its cellular biochemistry and physiology. However, knowledge regarding the regulation of overall metabolic routes in response to various environmental stresses is limited due to a lack of comprehensive, time-resolved metabolomic analyses. In this study, gas chromatography-mass spectrometry (GC-MS)-based metabolic profiling was performed to characterize the temporal variations of N. europaea 19718 intercellular metabolites in response to varied temperature (23 and 10 °C) and ammonia feeding patterns (shock loading and continuous feeding of 20 mg N/L). Approximately 87 metabolites were successfully identified and mapped to the existing pathways of N. europaea 19718, allowing interpretation of the influence of temperature and feeding pattern on metabolite levels. In general, varied temperature had a more profound influence on the overall metabolism than varied feeding patterns. Total extracellular metabolite concentrations (relative to internal standards and normalized to biomass weight) were lower under cold stress and shock loading conditions compared with the control (continuous feeding at 23 °C). Cold stress caused the widespread downregulation of metabolites involved in central carbon metabolism, amino acid, and lipid synthesis (e.g., malonic acid, succinic acid, putrescine, and phosphonolpyruvate). Metabolites that showed differences under varied feeding patterns were mainly involved in nucleotide acid, amino acid, and lipid metabolism (e.g., adenine, uracil, and spermidine). This study highlighted the roles of central carbon and nitrogen metabolism in countering cold stress and altered ammonia availability. In addition, transcriptomic, proteomic, and metabolomic data from three studies on N. europaea were compared to achieve a

  13. Oxidation of nitrapyrin to 6-chloropicolinic acid by the ammonia-oxidizing bacterium nitrosomonas europaea

    SciTech Connect

    Vannelli, T.; Hooper, A.B.

    1992-07-01

    Suspensions of Nitrosomonas europaea catalyzed the oxidation of the commercial nitrification inhibitor nitrapyrin (2-chloro-6-(trichloromethyl)-pyridine). Rapid oxidation of nitrapyrin (at a concentration of 10 microM) required the concomitant oxidation of ammonia, hydroxylamine, or hydrazine. The turnover rate was highest in the presence of 10 mM ammonia (0.8 nmol of nitrapyrin per min/mg of protein). The product of the reaction was 6-chloropicolinic acid. By the use of (18)O2, it was shown that one of the oxygens in 6-chloropicolinic acid came from diatomic oxygen and that the other came from water. Approximately 13% of the radioactivity of (2,6-(14)C) nitrapyrin was shown to bind to cells. Most (94%) of the latter was bound indiscriminately to membrane proteins. The nitrapyrin bound to membrane proteins may account for the observed inactivation of ammonia oxidation. (Copyright (c) 1992, American Society for Microbiology.)

  14. Redox state dependence of axial ligand dynamics in Nitrosomonas europaea cytochrome c552.

    PubMed

    Kaur, Ravinder; Bren, Kara L

    2013-12-12

    Analysis of NMR spectra reveals that the heme axial Met ligand orientation and dynamics in Nitrosomonas europaea cytochrome c552 (Ne cyt c) are dependent on the heme redox state. In the oxidized state, the heme axial Met is fluxional, interconverting between two conformers related to each other by inversion through the Met δS atom. In the reduced state, there is no evidence of fluxionality, with the Met occupying one conformation similar to that seen in the homologous Pseudomonas aeruginosa cytochrome c551. Comparison of the observed and calculated pseudocontact shifts for oxidized Ne cyt c using the reduced protein structure as a reference structure reveals a redox-dependent change in the structure of the loop bearing the axial Met (loop 3). Analysis of nuclear Overhauser effects (NOEs) and existing structural data provides further support for the redox state dependence of the loop 3 structure. Implications for electron transfer function are discussed.

  15. Removal of ammonia by immobilized Nitrosomonas europaea in a biotrickling filter packed with polyurethane foam.

    PubMed

    Ramírez, Martín; Gómez, José Manuel; Aroca, Germán; Cantero, Domingo

    2009-03-01

    A biotrickling filter with Nitrosomonas europaea immobilized on polyurethane foam is proposed for treating ammonia contaminated air. The effect of the surface velocity of the recirculation medium, nitrite concentration, pH, empty bed residence time (EBRT) and ammonia inlet load on the NH(3) removal process was investigated. The total amount of biomass immobilized on the carrier was 3.29+/-0.52 x 10(10) cells g(-1) dry carrier. The maximum elimination capacity of the biotrickling filter was 270 g Nm(-3)h(-1) at pH 7.5, an EBRT of 11s, and nitrite concentrations below 100mM. These results show that system studied can be considered as a viable alternative for the treatment of gaseous emissions containing high concentrations of ammonia.

  16. Identification of the sources of nitrous oxide produced by oxidative and reductive processes in Nitrosomonas europaea

    PubMed Central

    Ritchie, G. A. F.; Nicholas, D. J. D.

    1972-01-01

    1. Cells of Nitrosomonas europaea produced N2O during the oxidation of ammonia and hydroxylamine. 2. The end-product of ammonia oxidation, nitrite, was the predominant source of N2O in cells. 3. Cells also produced N2O, but not N2 gas, by the reduction of nitrite under anaerobic conditions. 4. Hydroxylamine was oxidized by cell-free extracts to yield nitrite and N2O aerobically, but to yield N2O and NO anaerobically. 5. Cell extracts reduced nitrite both aerobically and anaerobically to NO and N2O with hydroxylamine as an electron donor. 6. The relative amounts of NO and N2O produced during hydroxylamine oxidation and/or nitrite reduction are dependent on the type of artificial electron acceptor utilized. 7. Partially purified hydroxylamine oxidase retained nitrite reductase activity but cytochrome oxidase was absent. 8. There is a close association of hydroxylamine oxidase and nitrite reductase activities in purified preparations. PMID:5073730

  17. Physiologic and proteomic evidence for a role of nitric oxide in biofilm formation by Nitrosomonas europaea and other ammonia oxidizers.

    PubMed

    Schmidt, Ingo; Steenbakkers, Peter J M; op den Camp, Huub J M; Schmidt, Katrin; Jetten, Mike S M

    2004-05-01

    NO, a free radical gas, is the signal for Nitrosomonas europaea cells to switch between different growth modes. At an NO concentration of more than 30 ppm, biofilm formation by N. europaea was induced. NO concentrations below 5 ppm led to a reversal of the biofilm formation, and the numbers of motile and planktonic (motile-planktonic) cells increased. In a proteomics approach, the proteins expressed by N. europaea were identified. Comparison studies of the protein patterns of motile-planktonic and attached (biofilm) cells revealed several clear differences. Eleven proteins were found to be up or down regulated. Concentrations of other compounds such as ammonium, nitrite, and oxygen as well as different temperatures and pH values had no significant effect on the growth mode of and the proteins expressed by N. europaea.

  18. Physiologic and Proteomic Evidence for a Role of Nitric Oxide in Biofilm Formation by Nitrosomonas europaea and Other Ammonia Oxidizers

    PubMed Central

    Schmidt, Ingo; Steenbakkers, Peter J. M.; op den Camp, Huub J. M.; Schmidt, Katrin; Jetten, Mike S. M.

    2004-01-01

    NO, a free radical gas, is the signal for Nitrosomonas europaea cells to switch between different growth modes. At an NO concentration of more than 30 ppm, biofilm formation by N. europaea was induced. NO concentrations below 5 ppm led to a reversal of the biofilm formation, and the numbers of motile and planktonic (motile-planktonic) cells increased. In a proteomics approach, the proteins expressed by N. europaea were identified. Comparison studies of the protein patterns of motile-planktonic and attached (biofilm) cells revealed several clear differences. Eleven proteins were found to be up or down regulated. Concentrations of other compounds such as ammonium, nitrite, and oxygen as well as different temperatures and pH values had no significant effect on the growth mode of and the proteins expressed by N. europaea. PMID:15090520

  19. Monochloramine disinfection kinetics of Nitrosomonas europaea by propidium monoazide quantitative PCR and Live/dead BacLight methods.

    PubMed

    Wahman, David G; Wulfeck-Kleier, Karen A; Pressman, Jonathan G

    2009-09-01

    Monochloramine disinfection kinetics were determined for the pure-culture ammonia-oxidizing bacterium Nitrosomonas europaea (ATCC 19718) by two culture-independent methods, namely, Live/Dead BacLight (LD) and propidium monoazide quantitative PCR (PMA-qPCR). Both methods were first verified with mixtures of heat-killed (nonviable) and non-heat-killed (viable) cells before a series of batch disinfection experiments with stationary-phase cultures (batch grown for 7 days) at pH 8.0, 25 degrees C, and 5, 10, and 20 mg Cl(2)/liter monochloramine. Two data sets were generated based on the viability method used, either (i) LD or (ii) PMA-qPCR. These two data sets were used to estimate kinetic parameters for the delayed Chick-Watson disinfection model through a Bayesian analysis implemented in WinBUGS. This analysis provided parameter estimates of 490 mg Cl(2)-min/liter for the lag coefficient (b) and 1.6 x 10(-3) to 4.0 x 10(-3) liter/mg Cl(2)-min for the Chick-Watson disinfection rate constant (k). While estimates of b were similar for both data sets, the LD data set resulted in a greater k estimate than that obtained with the PMA-qPCR data set, implying that the PMA-qPCR viability measure was more conservative than LD. For N. europaea, the lag phase was not previously reported for culture-independent methods and may have implications for nitrification in drinking water distribution systems. This is the first published application of a PMA-qPCR method for disinfection kinetic model parameter estimation as well as its application to N. europaea or monochloramine. Ultimately, this PMA-qPCR method will allow evaluation of monochloramine disinfection kinetics for mixed-culture bacteria in drinking water distribution systems.

  20. A Bioluminescence Assay Using Nitrosomonas europaea for Rapid and Sensitive Detection of Nitrification Inhibitors

    PubMed Central

    Iizumi, Taro; Mizumoto, Masahiro; Nakamura, Kanji

    1998-01-01

    An expression vector for the luxAB genes, derived from Vibrio harveyi, was introduced into Nitrosomonas europaea. Although the recombinant strain produced bioluminescence due to the expression of the luxAB genes under normal growing conditions, the intensity of the light emission decreased immediately, in a time-and dose-dependent manner, with the addition of ammonia monooxygenase inhibitors, such as allylthiourea, phenol, and nitrapyrin. When whole cells were challenged with several nitrification inhibitors and toxic compounds, a close relationship was found between the change in the intensity of the light emission and the level of ammonia-oxidizing activity. The response of bioluminescence to the addition of allylthiourea was considerably faster than the change in the ammonia-oxidizing rate, measured as both the O2 uptake and NO2− production rates. The bioluminescence of cells inactivated by ammonia monooxygenase inhibitor was recovered rapidly by the addition of certain substrates for hydroxylamine oxidoreductase. These results suggested that the inhibition of bioluminescence was caused by the immediate decrease of reducing power in the cell due to the inactivation of ammonia monooxygenase, as well as by the destruction of other cellular metabolic pathways. We conclude that the assay system using luminous Nitrosomonas can be applied as a rapid and sensitive detection test for nitrification inhibitors, and it will be used to monitor the nitrification process in wastewater treatment plants. PMID:9758781

  1. Effects of selected pharmaceutically active compounds on the ammonia oxidizing bacterium Nitrosomonas europaea.

    PubMed

    Wang, Shuyi; Gunsch, Claudia K

    2011-01-01

    Pharmaceutically active compounds (PhACs) are commonly found in wastewater influent. However, little research has focused on determining their impact on fundamental processes in wastewater treatment such as nitrogen removal. In this study, focus was placed on 4 commonly occurring PhACs (ketoprofen, naproxen, carbamazepine and gemfibrozil). Their effect was ascertained in the ammonia oxidizing bacterium (AOB), Nitrosomonas europaea in terms of membrane integrity and nitrite production. These PhACs were shown to inhibit nitrite production at concentrations of 1 and 10 μM while no effect was observed at 0.1 μM. The maximum observed nitrification inhibition was 25%, 29%, 22% and 26% for ketoprofen, naproxen, carbamazepine and gemfibrozil, respectively. A decrease in the live/dead ratio ranging from 10% to 16% suggests that these PhACs affect membrane integrity in N.europaea. The difference in nitrite production between PhACs treated cells and non PhAC treated controls was still significant following washing suggesting that inhibition is irreversible. Finally, nitrite production when adjusted to the live fraction of cells was also found to decrease suggesting that PhACs inhibited the activity of surviving cells. These results suggest that the presence of PhACs may affect AOB activity and may impact nitrogen removal, a key function in wastewater treatment. Follow up studies with additional AOB and in mixed culture are needed to further confirm these results.

  2. Rapid and sensitive Nitrosomonas europaea biosensor assay for quantification of bioavailable ammonium sensu strictu in soil.

    PubMed

    Nguyen, Minh Dong; Risgaard-Petersen, Nils; Sørensen, Jan; Brandt, Kristian K

    2011-02-01

    Knowledge on bioavailable ammonium sensu strictu (i.e., immediately available for cellular uptake) in soil is required to understand nutrient uptake processes in microorganisms and thus of vital importance for plant production. We here present a novel ammonium biosensor approach based on the lithoautotrophic ammonia-oxidizing bacterium Nitrosomonas europaea transformed with a luxAB sensor plasmid. Bioluminescence-based ammonium detection was achieved within 10 min with a quantification limit in liquid samples of ∼20 μM and a linear response range up to 400 μM. Biosensor and conventional chemical quantification of ammonium in soil solutions agreed well across a range of sample and assay conditions. The biosensor was subsequently applied for a solid phase-contact assay allowing for direct interaction of biosensor cells with soil particle-associated (i.e., exchangeable plus fixed) ammonium. The assay successfully quantified bioavailable ammonium even in unfertilized soil and demonstrated markedly higher ratios of bioavailable ammonium to water- or 2 M KCl-exchangeable ammonium in anoxic soil than in corresponding oxic soil. Particle-associated ammonium contributed by at least 74% and 93% of the total bioavailable pool in oxic and anoxic soil, respectively. The N. europaea biosensor should have broad relevance for environmental monitoring of bioavailable ammonium and processes depending on ammonium bioavailability.

  3. Influence of bovine serum albumin and alginate on silver nanoparticle dissolution and toxicity to Nitrosomonas europaea.

    PubMed

    Ostermeyer, Ann-Kathrin; Kostigen Mumuper, Cameron; Semprini, Lewis; Radniecki, Tyler

    2013-12-17

    Bovine serum albumin (BSA), a model protein, reduced the toxicity of 20 nm citrate silver nanoparticles (AgNP) toward Nitrosomonas europaea, a model ammonia oxidizing bacteria, through a dual-mode protection mechanism. BSA reduced AgNP toxicity by chelating the silver ions (Ag(+)) released from the AgNPs. BSA further reduced AgNP toxicity by binding to the AgNP surface thus preventing NH3-dependent dissolution from occurring. Due to BSA's affinity toward Ag(+) chemisorbed on the AgNP surface, increased concentrations of BSA lead to increased AgNP dissolution rates. This, however, did not increase AgNP toxicity as the dissolved Ag(+) were adsorbed onto the BSA molecules. Alginate, a model extracellular polysaccharide (EPS), lacks strong Ag(+) ligands and was unable to protect N. europaea from Ag(+) toxicity. However, at high concentrations, alginate reduced AgNP toxicity by binding to the AgNP surface and reducing AgNP dissolution rates. Unlike BSA, alginate only weakly interacted with the AgNP surface and was unable to completely prevent NH3-dependent AgNP dissolution from occurring. Based on these results, AgNP toxicity in high protein environments (e.g., wastewater) is expected to be muted while the EPS layers of wastewater biofilms may provide additional protection from AgNPs, but not from Ag(+) that have already been released.

  4. Transcription of genes coding for metabolic key functions in Nitrosomonas europaea during aerobic and anaerobic growth.

    PubMed

    Beyer, Sonja; Gilch, Stefan; Meyer, Ortwin; Schmidt, Ingo

    2009-01-01

    Nitrosomonas europaea can grow under conditions of chemolithoautotrophic aerobic (oxygen as oxidant) as well as anaerobic [nitrogen dioxide (NO(2)) as oxidant] nitrification or chemoorganotrophic anaerobic pyruvate-dependent denitrification. In this study, the adaptation of the transcription (mRNA synthesis/concentration) of N. europaea to aerobic and anaerobic growth conditions was evaluated and the transcription of genes coding for metabolic key functions was analyzed: nitrogen and energy metabolism (amoA, hao, rh1, nirK, norB, nsc, aceE, ldhA, ppc, gltA, odhA, coxA), carbon dioxide fixation (cbbL), gluconeogenesis (ppsA), cell growth (ftsZ), and oxidative stress (sodB). During aerobic ammonia oxidation the specific activities of ammonia oxidation, nitrite reduction, and the growth rates correlated with the transcription level of the corresponding genes amoA/hao, nirK/norB/nsc, and cbbL/ftsZ. In anaerobically ammonia-oxidizing cells of N. europaea, the cellular mRNA concentrations of amoA, hao, rh1,coxA, cbbL, ftsZ, and sodB were reduced compared with aerobically nitrifying cells, but the mRNA levels of nirK, norB, and nsc were significantly increased. During anaerobic pyruvate-dependent denitrification, the mRNA abundance of nirK, norB, nsc, aceE, gltA, and odhA was increased, while the concentrations of amoA,hao, rh1, coxAcbbL, ftsZ, and sodB were significantly reduced. Temperature, pH value, and NH(4)(+), O(2), NO, and NO(2) concentrations had comparatively small effects on the transcription of the studied genes.

  5. Candidate stress genes of Nitrosomonas europaea for monitoring inhibition of nitrification by heavy metals.

    PubMed

    Park, Sunhwa; Ely, Roger L

    2008-09-01

    Heavy metals have been shown to be strong inhibitors of nitrification in wastewater treatment plants. In this research, the effects of cadmium, copper, and mercury on Nitrosomonas europaea were studied in quasi-steady-state batch reactors. When cells were exposed to 1 microM CdCl2, 6 microM HgCl2, or 8 microM CuCl2, ammonia oxidation rates were decreased by about 90%. Whole-genome transcriptional and proteomic responses of N. europaea to cadmium were used to identify heavy metal stress response genes. When cells were exposed to 1 microM CdCl2 for 1 h, 66 genes (of the total of 2,460 genes) were upregulated, and 50 genes were downregulated more than twofold. Of these, the mercury resistance genes (merTPCADE) averaged 277-fold upregulation under 1 microM CdCl2, with merA (mercuric reductase) showing 297-fold upregulation. In N. europaea cells exposed to 6 microM HgCl2 or to 8 microM CuCl2, merA showed 250-fold and 1.7-fold upregulation, respectively. Cells showed the ability to recover quickly from Hg2+-related toxic effects, apparently associated with upregulation of the mercury resistance genes and amoA, but no such recovery was evident in Cd2+-exposed cells even though merTPCADE were highly upregulated. We suggest that the upregulation of merA in response to CdCl2 and HgCl2 exposure may provide a means to develop an early-warning indicator for inhibition of nitrification by these metals.

  6. Candidate Stress Genes of Nitrosomonas europaea for Monitoring Inhibition of Nitrification by Heavy Metals ▿

    PubMed Central

    Park, Sunhwa; Ely, Roger L.

    2008-01-01

    Heavy metals have been shown to be strong inhibitors of nitrification in wastewater treatment plants. In this research, the effects of cadmium, copper, and mercury on Nitrosomonas europaea were studied in quasi-steady-state batch reactors. When cells were exposed to 1 μM CdCl2, 6 μM HgCl2, or 8 μM CuCl2, ammonia oxidation rates were decreased by about 90%. Whole-genome transcriptional and proteomic responses of N. europaea to cadmium were used to identify heavy metal stress response genes. When cells were exposed to 1 μM CdCl2 for 1 h, 66 genes (of the total of 2,460 genes) were upregulated, and 50 genes were downregulated more than twofold. Of these, the mercury resistance genes (merTPCADE) averaged 277-fold upregulation under 1 μM CdCl2, with merA (mercuric reductase) showing 297-fold upregulation. In N. europaea cells exposed to 6 μM HgCl2 or to 8 μM CuCl2, merA showed 250-fold and 1.7-fold upregulation, respectively. Cells showed the ability to recover quickly from Hg2+-related toxic effects, apparently associated with upregulation of the mercury resistance genes and amoA, but no such recovery was evident in Cd2+-exposed cells even though merTPCADE were highly upregulated. We suggest that the upregulation of merA in response to CdCl2 and HgCl2 exposure may provide a means to develop an early-warning indicator for inhibition of nitrification by these metals. PMID:18606795

  7. Engineering of Nitrosomonas europaea to express Vitreoscilla hemoglobin enhances oxygen uptake and conversion of ammonia to nitrite.

    PubMed

    Kunkel, Stephanie A; Pagilla, Krishna R; Stark, Benjamin C

    2015-12-01

    Nitrosomonas europaea was transformed with a recombinant plasmid bearing the gene (vgb) encoding the hemoglobin (VHb) from the bacterium Vitreoscilla under control of the N. europaea amoC P1 promoter. Vgb was maintained stably and appeared to be expressed in the transformants at VHb levels of about 0.75 nmol/g wet weight. Expression of VHb in the N. europaea transformants was correlated with an approximately 2 fold increase in oxygen uptake rate by whole cells at oxygen concentrations in the range of 75-100% saturation, but no change in oxygen uptake rate at oxygen concentrations below 25% saturation. VHb expression was also correlated with an increase of as much as about 30% in conversion of ammonia to nitrite by growing cells. The results suggest that engineering of key aerobic wastewater bacteria to express bacterial hemoglobins may be a useful strategy to produce species with enhanced respiratory abilities.

  8. Activity-Based Protein Profiling of Ammonia Monooxygenase in Nitrosomonas europaea.

    PubMed

    Bennett, Kristen; Sadler, Natalie C; Wright, Aaron T; Yeager, Chris; Hyman, Michael R

    2016-04-01

    Nitrosomonas europaea is an aerobic nitrifying bacterium that oxidizes ammonia (NH3) to nitrite (NO2 (-)) through the sequential activities of ammonia monooxygenase (AMO) and hydroxylamine dehydrogenase (HAO). Many alkynes are mechanism-based inactivators of AMO, and here we describe an activity-based protein profiling method for this enzyme using 1,7-octadiyne (17OD) as a probe. Inactivation of NH4 (+)-dependent O2 uptake by N. europaea by 17OD was time- and concentration-dependent. The effects of 17OD were specific for ammonia-oxidizing activity, andde novoprotein synthesis was required to reestablish this activity after cells were exposed to 17OD. Cells were reacted with Alexa Fluor 647 azide using a copper-catalyzed azide-alkyne cycloaddition (CuAAC) (click) reaction, solubilized, and analyzed by SDS-PAGE and infrared (IR) scanning. A fluorescent 28-kDa polypeptide was observed for cells previously exposed to 17OD but not for cells treated with either allylthiourea or acetylene prior to exposure to 17OD or for cells not previously exposed to 17OD. The fluorescent polypeptide was membrane associated and aggregated when heated with β-mercaptoethanol and SDS. The fluorescent polypeptide was also detected in cells pretreated with other diynes, but not in cells pretreated with structural homologs containing a single ethynyl functional group. The membrane fraction from 17OD-treated cells was conjugated with biotin-azide and solubilized in SDS. Streptavidin affinity-purified polypeptides were on-bead trypsin-digested, and amino acid sequences of the peptide fragments were determined by liquid chromatography-mass spectrometry (LC-MS) analysis. Peptide fragments from AmoA were the predominant peptides detected in 17OD-treated samples. In-gel digestion and matrix-assisted laser desorption ionization-tandem time of flight (MALDI-TOF/TOF) analyses also confirmed that the fluorescent 28-kDa polypeptide was AmoA.

  9. Electron paramagnetic studies of the copper and iron containing soluble ammonia monooxygenase from Nitrosomonas europaea.

    PubMed

    Gilch, Stefan; Meyer, Ortwin; Schmidt, Ingo

    2010-08-01

    Soluble ammonia monooxygenase (AMO) from Nitrosomonas europaea was purified to homogeneity and metals in the active sites of the enzyme (Cu, Fe) were analyzed by electron paramagnetic resonance (EPR) spectroscopy. EPR spectra were obtained for a type 2 Cu(II) site with g(parallel) = 2.24, A(parallel) = 18.4 mT and g(perpendicular) = 2.057 as well as for heme and non heme iron present in purified soluble AMO from N. europaea. A second type 2 Cu(II) EPR signal with g(parallel) = 2.29, A(parallel) = 16.1 mT and g(perpendicular) = 2.03 appeared in the spectrum of the ferricyanide oxidized enzyme and was attributed to oxidation of cuprous sites. Comparison of EPR-detectable Cu(2+) with total copper determined by inductively coupled plasma-mass spectrometry (ICP-MS) suggests that there are six paramagnetic Cu(2+) and three diamagnetic Cu(1+) per heterotrimeric soluble AMO (two paramagnetic and one diamagnetic Cu per alphabetagamma-protomer). A trigonal EPR signal at g = 6.01, caused by a high-spin iron, indicative for cytochrome bound iron, and a rhombic signal at g = 4.31, characteristic of specifically bound Fe(3+) was detectable. The binding of nitric oxide in the presence of reductant resulted in a ferrous S = 3/2 signal, characteristic of a ferrous nitrosyl complex. Inactivation of soluble AMO with acetylene did neither diminish the ferrous signal nor the intensity of the Cu(2+)-EPR signal.

  10. NO Reductase Activity of the Tetraheme Cytochrome c554 of Nitrosomonas europaea

    PubMed Central

    Upadhyay, Anup K.; Hooper, Alan B.; Hendrich, Michael P.

    2009-01-01

    The tetraheme cytochrome c554 (cyt c554) from Nitrosomonas europaea is believed to function as an electron-transfer protein from hydroxylamine oxidoreductase (HAO). We show here that cyt c554 also has significant NO reductase activity. The protein contains one high-spin and three low-spin c-type hemes. HAO catalyzed reduction of the cyt c554, ligand binding, intermolecular electron transfer, and kinetics of NO reduction by cyt c554 have been investigated. We detect the formation of a NO-bound ferrous heme species in cyt c554 by EPR and Mössbauer spectroscopies during the HAO catalyzed oxidation of hydroxylamine, indicating that N-oxide intermediates produced from HAO readily bind to cyt c554. In the half-reduced state of cyt c554, we detect a spin interaction between the [FeNO]7 state of heme 2 and the low-spin ferric state of heme 4. We find that ferrous cyt c554 will reduce NO at a rate greater than 16 s−1, which is comparable to rates of other known NO reductases. Carbon monoxide or nitrite are shown not to bind to the reduced protein, and previous results indicate the reactions with O2 are slow and that a variety of ligands will not bind in the oxidized state. Thus, the enzymatic site is highly selective for NO. The NO reductase activity of cyt c554 may be important during ammonia oxidation in N. europaea at low oxygen concentrations to detoxify NO produced by reduction of nitrite or incomplete oxidation of hydroxylamine. PMID:16569009

  11. Activity-Based Protein Profiling of Ammonia Monooxygenase in Nitrosomonas europaea

    PubMed Central

    Bennett, Kristen; Sadler, Natalie C.; Wright, Aaron T.; Yeager, Chris

    2016-01-01

    Nitrosomonas europaea is an aerobic nitrifying bacterium that oxidizes ammonia (NH3) to nitrite (NO2−) through the sequential activities of ammonia monooxygenase (AMO) and hydroxylamine dehydrogenase (HAO). Many alkynes are mechanism-based inactivators of AMO, and here we describe an activity-based protein profiling method for this enzyme using 1,7-octadiyne (17OD) as a probe. Inactivation of NH4+-dependent O2 uptake by N. europaea by 17OD was time- and concentration-dependent. The effects of 17OD were specific for ammonia-oxidizing activity, and de novo protein synthesis was required to reestablish this activity after cells were exposed to 17OD. Cells were reacted with Alexa Fluor 647 azide using a copper-catalyzed azide-alkyne cycloaddition (CuAAC) (click) reaction, solubilized, and analyzed by SDS-PAGE and infrared (IR) scanning. A fluorescent 28-kDa polypeptide was observed for cells previously exposed to 17OD but not for cells treated with either allylthiourea or acetylene prior to exposure to 17OD or for cells not previously exposed to 17OD. The fluorescent polypeptide was membrane associated and aggregated when heated with β-mercaptoethanol and SDS. The fluorescent polypeptide was also detected in cells pretreated with other diynes, but not in cells pretreated with structural homologs containing a single ethynyl functional group. The membrane fraction from 17OD-treated cells was conjugated with biotin-azide and solubilized in SDS. Streptavidin affinity-purified polypeptides were on-bead trypsin-digested, and amino acid sequences of the peptide fragments were determined by liquid chromatography-mass spectrometry (LC-MS) analysis. Peptide fragments from AmoA were the predominant peptides detected in 17OD-treated samples. In-gel digestion and matrix-assisted laser desorption ionization–tandem time of flight (MALDI-TOF/TOF) analyses also confirmed that the fluorescent 28-kDa polypeptide was AmoA. PMID:26826234

  12. Axenic cultures of Nitrosomonas europaea and Nitrobacter winogradskyi in autotrophic conditions: a new protocol for kinetic studies.

    PubMed

    Farges, B; Poughon, L; Roriz, D; Creuly, C; Dussap, C-G; Lasseur, C

    2012-07-01

    As a part of a natural biological N-cycle, nitrification is one of the steps included in the conception of artificial ecosystems designed for extraterrestrial life support systems (LSS) such as Micro-Ecological Life Support System Alternative (MELiSSA) project, which is the LSS project of the European Space Agency. Nitrification in aerobic environments is carried out by two groups of bacteria in a two-step process. The ammonia-oxidizing bacteria (Nitrosomonas europaea) realize the oxidation of ammonia to nitrite, and the nitrite-oxidizing bacteria (Nitrobacter winogradskyi), the oxidation of nitrite to nitrate. In both cases, the bacteria achieve these oxidations to obtain an energy and reductant source for their growth and maintenance. Furthermore, both groups also use CO₂ predominantly as their carbon source. They are typically found together in ecosystems, and consequently, nitrite accumulation is rare. Due to the necessity of modeling accurately conversion yields and transformation rates to achieve a complete modeling of MELiSSA, the present study focuses on the experimental determination of nitrogen to biomass conversion yields. Kinetic and mass balance studies for axenic cultures of Nitrosomonas europaea and Nitrobacter winogradskyi in autotrophic conditions are performed. The follow-up of these cultures is done using flow cytometry for assessing biomass concentrations and ionic chromatography for ammonium, nitrite, and nitrate concentrations. A linear correlation is observed between cell count and optical density (OD) measurement (within a 10 % accuracy) validating OD measurements for an on-line estimation of biomass quantity even at very low biomass concentrations. The conversion between cell count and biomass concentration has been determined: 7.1 × 10¹² cells g dry matter (DM)⁻¹ for Nitrobacter and 6.3 × 10¹² cells g DM⁻¹ for Nitrosomonas. Nitrogen substrates and products are assessed redundantly showing excellent agreement for mass

  13. Influence of ammonia on silver nanoparticle dissolution and toxicity to Nitrosomonas europaea.

    PubMed

    Kostigen Mumper, Cameron; Ostermeyer, Ann-Kathrin; Semprini, Lewis; Radniecki, Tyler S

    2013-11-01

    Nitrosomonas europaea, a model ammonia oxidizing bacterium, was sensitive to both ionic silver (Ag(+)) and 20 nm citrate capped silver nanoparticles (AgNPs). AgNP toxicity has been previously shown to be primarily due to the dissolution of Ag(+). The rate of AgNP dissolution dramatically increased in test medium containing ammonium sulfate ((NH4)2SO4) and HEPES buffer compared to test medium containing either deionized water or HEPES buffer alone. The AgNP dissolution rates accelerated with increases in ammonia (NH3) concentrations either through increases in pH or through higher (NH4)2SO4 concentrations. Ammonia likely participated in the oxidation of the AgNP to form [Formula: see text] in solution leading to the observed increase in AgNP dissolution rates. AgNP toxicity was enhanced as NH3 concentrations increased. However, Ag(+) toxicity was constant at all NH3 concentrations tested. Therefore, it can be concluded that the increased AgNP toxicity was due to increased Ag(+) release and not due to a synergistic effect between NH3 and Ag(+). The results of this study may provide insights in the fate and toxicity of AgNPs in high NH3 environments including wastewater treatment plants, eutrophic waterways and alkaline environments.

  14. Impacts of silver nanoparticle coating on the nitrification potential of Nitrosomonas europaea.

    PubMed

    Arnaout, Christina L; Gunsch, Claudia K

    2012-05-15

    Silver nanoparticles (AgNPs) are increasingly used as bacteriostatic agents to prevent microbial growth. AgNPs are manufactured with a variety of coatings, and their potential impacts on wastewater treatment in general are poorly understood. In the present study, Nitrosomonas europaea, a model ammonia oxidizing bacterium, was exposed to AgNPs with citrate, gum arabic (GA), and polyvinylpyrrolidone (PVP). GA and citrate AgNPs inhibited nitrification most strongly (67.9 ± 3.6% and 91.4 ± 0.2%, respectively at 2 ppm). Our data indicate that Ag(+) dissolution and colloid stability of AgNPs were the main factors in AgNP toxicity. In general, low amounts of dissolved Ag initially caused a post-transcriptional interruption of membrane-bound nitrifying enzyme function, reducing nitrification by 10% or more. A further increase in dissolved Ag resulted in heavy metal stress response (e.g., merA up-regulation) and ultimately led to membrane disruption. The highest effect on membrane disruption was observed for citrate AgNPs (64 ± 11% membranes compromised at 2 ppm), which had high colloidal stability. This study demonstrates that coating plays a very important role in determining Ag dissolution and ultimately toxicity to nitrifiers. More research is needed to characterize these parameters in complex growth media such as wastewater.

  15. Crystal structure of a novel red copper protein from Nitrosomonas europaea

    SciTech Connect

    Lieberman, R.L.; Arciero, D.M.; Hooper, A.B.; Rosenzweig, A.C.

    2010-03-08

    Nitrosocyanin (NC) is a mononuclear red copper protein isolated from the ammonia oxidizing bacterium Nitrosomonas europaea. Although NC exhibits some sequence homology to classic blue copper proteins, its spectroscopic and electrochemical properties are drastically different. The 1.65 {angstrom} resolution crystal structure of oxidized NC reveals an unprecedented trimer of single domain cupredoxins. Each copper center is partially covered by an unusual extended {beta}-hairpin structure from an adjacent monomer. The copper ion is coordinated by His 98, His 103, Cys 95, a single side chain oxygen of Glu 60, and a solvent molecule. In the 2.3 {angstrom} resolution structure of reduced NC, His 98 shifts away from the copper ion, and the solvent molecule is not observed. The arrangement of these ligands renders the coordination geometry of the NC red copper center distinct from that of blue copper centers. In particular, the red copper center has a higher coordination number and lacks the long Cu-S(Met) and short Cu-S(Cys) bond distances characteristic of blue copper. Moreover, the red copper center is square pyramidal whereas blue copper is typically distorted tetrahedral. Analysis of the NC structure provides insight into possible functions of this new type of biological copper center.

  16. X- and Q-band EPR Studies of the Tetraheme Cytochrome c554 from Nitrosomonas europaea

    NASA Astrophysics Data System (ADS)

    Petasis, Doros; Culver, Caleb; Hendrich, Michael

    2001-04-01

    Cytochrome c554 (cyt c554) is a tetraheme cytochrome from the bacteria Nitrosomonas europaea that participate in the assimilation of nitrogen into plants from industrially fixed Nsub2 by oxidizing ammonia to nitrite. These autotrophic bacteria metabolize ammonia as the sole source of energy through a two-step process. In the first step, the membrane-bound enzyme ammonia monooxygenase (AMO) catalyzes the oxidation of ammonia to hydroxylamine (NH3+O2+2e-+2H+ä_NH2OH+H2O). In the second step, hydroxylamine oxidoreductase (HAO) oxidizes hydroxylamine to nitrite (NH2OH+H2Oä_NO2-+4e-+5H+). Cyt c554 accepts electrons from HAO and transports them to either AMO or the ubiquinone pool. HAO is one of the most complicated heme systems known, consisting of 24 hemes in a circular arrangement. A large region of HAO matches the tertiary structure of cyt c554, so determining the electronic structure of the simpler protein cyt c554 will help in understanding the electronic structure of the active site of the more complex HAO enzyme. We have collected perpendicular and parallel mode EPR data at X- and Q-band frequencies (9 and 34 GHz respectively) of the native cyt c554 protein and a series of reduced samples in an effort to understand the role of each heme in electron transport. The novel features of these spectra were simulated using techniques developed at CMU and will be discussed.

  17. Changes in ammonia oxidiser population during transition to low pH in a biofilm reactor starting with Nitrosomonas europaea.

    PubMed

    Tarre, S; Shlafman, E; Beliavski, M; Green, M

    2007-01-01

    Recent experiments in our laboratory using both biofilm and suspended biomass reactors have demonstrated high rate nitrification at low pH with known autotrophic nitrifying bacteria originating from wastewater treatment plants refuting previous assumptions that nitrification is significantly inhibited at low pH. Since much of the earlier microbiological work regarding ammonia oxidising bacteria (AOB) physiology was carried out using Nitrosomonas europaea, this model bacterium's capability for high rate nitrification at low pH in a continuous biofilm reactor was tested. A biofilm reactor filled with sintered glass particles was inoculated with a pure culture of N. europaea. The reactor was first operated to high nitrification rates under conditions favourable to N. europaea (pH > 7; high ammonium concentrations). To eliminate inhibitory concentrations of nitrite at low pH, an enriched culture of Nitrospira (a nitrite oxidising bacterium) was then added. The transition from neutral to acidic conditions was attempted by sharply lowering the nitrification rate and by using a feeding solution containing insufficient buffer for complete nitrification. As opposed to other successful transitions, the pH in the N. europaea/Nitrospira reactor initially dropped only slightly and maintained pH > 6 for over two weeks. The reactor reached pH 4.5 only after four weeks. FISH results showed that while the percent of AOB and Nitrospira to eubacteria remained relatively constant at 51.1 +/- 8.2% and 40.8 +/- 6.4%, respectively, the AOB community changed completely in 60 days from 100% N. europaea to 100% Nitrosomonas oligotropha. Even though N. oligotropha was not intentionally introduced into the reactor, it is apparently much better adapted to conditions of low pH.

  18. Transcript Analysis of Multiple Copies of amo (Encoding Ammonia Monooxygenase) and hao (Encoding Hydroxylamine Oxidoreductase) in Nitrosomonas europaea

    PubMed Central

    Hommes, Norman G.; Sayavedra-Soto, Luis A.; Arp, Daniel J.

    2001-01-01

    The genes encoding ammonia monooxygenase (amoCAB), hydroxylamine oxidoreductase (hao), and the c-type cytochrome c-554 (hcy) are present in multiple copies in the genome of Nitrosomonas europaea. The upstream regions of the two copies of amoC, the three copies of hao, and one copy of hcy were cloned and sequenced. Primer extension reactions were done to identify transcription start sites for these genes, as well as for amoA. Putative ς70 promoter sequences were found associated with all but one of the mapped transcription start sites. Primer extensions were done with amoC primers using RNA harvested from cells incubated with and without ammonium. The experiments suggested that N. europaea cells may be able to use different promoters in the presence and absence of ammonium. PMID:11208810

  19. Activity-Based Protein Profiling of Ammonia Monooxygenase in Nitrosomonas europaea

    SciTech Connect

    Bennett, Kristen; Sadler, Natalie C.; Wright, Aaron T.; Yeager, Chris; Hyman, Michael R.; Löffler, F. E.

    2016-01-29

    Nitrosomonas europaeais an aerobic nitrifying bacterium that oxidizes ammonia (NH3) to nitrite (NO2) through the sequential activities of ammonia monooxygenase (AMO) and hydroxylamine dehydrogenase (HAO). Many alkynes are mechanism-based inactivators of AMO, and here we describe an activity-based protein profiling method for this enzyme using 1,7-octadiyne (17OD) as a probe. Inactivation of NH4+-dependent O2uptake byN. europaeaby 17OD was time- and concentration-dependent. The effects of 17OD were specific for ammonia-oxidizing activity, andde novoprotein synthesis was required to reestablish this activity after cells were exposed to 17OD. Cells were reacted with Alexa Fluor 647 azide using a copper-catalyzed azide-alkyne cycloaddition (CuAAC) (click) reaction, solubilized, and analyzed by SDS-PAGE and infrared (IR) scanning. A fluorescent 28-kDa polypeptide was observed for cells previously exposed to 17OD but not for cells treated with either allylthiourea or acetylene prior to exposure to 17OD or for cells not previously exposed to 17OD. The fluorescent polypeptide was membrane associated and aggregated when heated with β-mercaptoethanol and SDS. The fluorescent polypeptide was also detected in cells pretreated with other diynes, but not in cells pretreated with structural homologs containing a single ethynyl functional group. The membrane fraction from 17OD-treated cells was conjugated with biotin-azide and solubilized in SDS. Streptavidin affinity-purified polypeptides were on-bead trypsin-digested, and amino acid sequences of the peptide fragments were determined by liquid chromatography-mass spectrometry (LC-MS) analysis. Peptide fragments from AmoA were the predominant peptides detected in 17OD-treated samples. In-gel digestion and matrix

  20. Construction of recombinant Nitrosomonas europaea expressing green fluorescent protein in response to co-oxidation of chloroform.

    PubMed

    Gvakharia, Barbara O; Bottomley, Peter J; Arp, Daniel J; Sayavedra-Soto, Luis A

    2009-04-01

    Transcriptional fusions with gfp driven by the promoter region of mbla (NE2571) in pPRO/mbla4 and clpB (NE2402) in pPRO/clpb7 were used to transform the ammonia-oxidizing bacterium Nitrosomonas europaea (ATCC 19718). The two genes were chosen because their transcript levels were found at much higher levels in N. europaea in response to oxidation of chloroform and chloromethane. In N. europaea transformed with pPRO/mbla4, green fluorescent protein (GFP)-dependent fluorescence increased from 3- to 18-fold above control levels in response to increasing chloroform concentrations (7 to 28 microM), and from 8- to 10-fold in response to increasing hydrogen peroxide concentrations (2.5-7.5 mM). The GFP-dependent fluorescence of N. europaea transformed with pPRO/clpb7 also showed an increase of 6- to 10-fold in response to chloroform (28-100 microM) but did not respond to H(2)O(2). Our data provide proof of concept that biosensors can be fabricated in ammonia-oxidizing bacteria using "sentinel" genes that up-regulate in response to stress caused either by co-oxidation of chlorinated solvents or by the presence of H(2)O(2). The fabricated biosensors had a consistent concentration-dependent response to chloroform; however, these did not respond to other chlorinated compounds that cause similar cellular stress.

  1. Evolution and functional characterization of the RH50 gene from the ammonia-oxidizing bacterium Nitrosomonas europaea.

    PubMed

    Cherif-Zahar, Baya; Durand, Anne; Schmidt, Ingo; Hamdaoui, Nabila; Matic, Ivan; Merrick, Mike; Matassi, Giorgio

    2007-12-01

    The family of ammonia and ammonium channel proteins comprises the Amt proteins, which are present in all three domains of life with the notable exception of vertebrates, and the homologous Rh proteins (Rh50 and Rh30) that have been described thus far only in eukaryotes. The existence of an RH50 gene in bacteria was first revealed by the genome sequencing of the ammonia-oxidizing bacterium Nitrosomonas europaea. Here we have used a phylogenetic approach to study the evolution of the N. europaea RH50 gene, and we show that this gene, probably as a component of an integron cassette, has been transferred to the N. europaea genome by horizontal gene transfer. In addition, by functionally characterizing the Rh50(Ne) protein and the corresponding knockout mutant, we determined that NeRh50 can mediate ammonium uptake. The RH50(Ne) gene may thus have replaced functionally the AMT gene, which is missing in the genome of N. europaea and may be regarded as a case of nonorthologous gene displacement.

  2. Role of Nitrosomonas europaea NitABC iron transporter in the uptake of Fe3+-siderophore complexes.

    PubMed

    Vajrala, Neeraja; Sayavedra-Soto, Luis A; Bottomley, Peter J; Arp, Daniel J

    2010-11-01

    Nitrosomonas europaea has a single three-gene operon (nitABC) encoding an iron ABC transporter system (NitABC). Phylogenetic analysis clustered the subunit NitB with Fe(3+)-ABC transporter permease components from other organisms. The N. europaea strain deficient in nitB (nitB::kan) grew well in either Fe-replete or Fe-limited media and in Fe-limited medium containing the catecholate-type siderophore, enterobactin or the citrate-based dihydroxamate-type siderophore, aerobactin. However, the nitB::kan mutant strain was unable to grow in Fe-limited media containing either the hydroxamate-type siderophores, ferrioxamine and ferrichrome or the mixed-chelating type siderophore, pyoverdine. Exposure of N. europaea cells to a ferrichrome analog coupled to the fluorescent moiety naphthalic diimide (Fhu-NI) led to increase in fluorescence in the wild type but not in nitB::kan mutant cells. Spheroplasts prepared from N. europaea wild type exposed to Fhu-NI analog retained the fluorescence, while spheroplasts of the nitB::kan mutant were not fluorescent. NitABC transports intact Fe(3+)-ferrichrome complex into the cytoplasm and is an atypical ABC type iron transporter for Fe(3+) bound to ferrioxamine, ferrichrome or pyoverdine siderophores into the cytoplasm. The mechanisms to transport iron in either the Fe(3+) or Fe(2+) forms or Fe(3+) associated with enterobactin or aerobactin siderophores into the cell across the cytoplasmic membrane are as yet undetermined.

  3. Toxicity of binary mixtures of metal oxide nanoparticles to Nitrosomonas europaea.

    PubMed

    Yu, Ran; Wu, Junkang; Liu, Meiting; Zhu, Guangcan; Chen, Lianghui; Chang, Yan; Lu, Huijie

    2016-06-01

    Although the widely used metal oxide nanoparticles (NPs) titanium dioxide NPs (n-TiO2), cerium dioxide NPs (n-CeO2), and zinc oxide NPs (n-ZnO) have been well known for their potential cytotoxicities to environmental organisms, their combined effects have seldom been investigated. In this study, the short-term binary effect of n-CeO2 and n-TiO2 or n-ZnO on a model ammonia oxidizing bacterium, Nitrosomonas europaea were evaluated based on the examinations of cells' physiological, metabolic, and transcriptional responses. The addition of n-TiO2 mitigated the negative effect of more toxic n-CeO2 and the binary toxicity (antagonistic toxicity) of n-TiO2 and n-CeO2 was generally lower than the single NPs induced one. While the n-CeO2/n-ZnO mixture exerted higher cytotoxicity (synergistic cytotoxicity) than that from single NPs. The increased addition of the less toxic n-CeO2 exaggerated the binary toxicity of n-CeO2/n-ZnO mixture although the solubility of n-ZnO was not significantly affected, which excluded the contribution of the dissolved Zn ions to the enhancement of the combined cytotoxicity. The cell membrane disturbances and NP internalizations were detected for all the NP impacted cultures and the electrostatic interactions among the two distinct NPs and the cells were expected to play a key role in mediating their direct contacts and the eventual binary nanotoxicity to the cells.

  4. Kinetic and product distribution analysis of NO* reductase activity in Nitrosomonas europaea hydroxylamine oxidoreductase.

    PubMed

    Kostera, Joshua; Youngblut, Matthew D; Slosarczyk, Jeffrey M; Pacheco, A Andrew

    2008-09-01

    Hydroxylamine oxidoreductase (HAO) from the ammonia-oxidizing bacterium Nitrosomonas europaea normally catalyzes the four-electron oxidation of hydroxylamine to nitrite, which is the second step in ammonia-dependent respiration. Here we show that, in the presence of methyl viologen monocation radical (MV(red)), HAO can catalyze the reduction of nitric oxide to ammonia. The process is analogous to that catalyzed by cytochrome c nitrite reductase, an enzyme found in some bacteria that use nitrite as a terminal electron acceptor during anaerobic respiration. The availability of a reduction pathway to ammonia is an important factor to consider when designing in vitro studies of HAO, and may also have some physiological relevance. The reduction of nitric oxide to ammonia proceeds in two kinetically distinct steps: nitric oxide is first reduced to hydroxylamine, and then hydroxylamine is reduced to ammonia at a tenfold slower rate. The second step was investigated independently in solutions initially containing hydroxylamine, MV(red), and HAO. Both steps show first-order dependence on nitric oxide and HAO concentrations, and zero-order dependence on MV(red) concentration. The rate constants governing each reduction step were found to have values of (4.7 +/- 0.3) x 10(5) and (2.06 +/- 0.04) x 10(4) M(-1) s(-1), respectively. A second reduction pathway, with second-order dependence on nitric oxide, may become available as the concentration of nitric oxide is increased. Such a pathway might lead to production of nitrous oxide. We estimate a maximum value of (1.5 +/- 0.05) x 10(10) M(-2) s(-1) for the rate constant of the alternative pathway, which is small and suggests that the pathway is not physiologically important.

  5. A specific inorganic triphosphatase from Nitrosomonas europaea: structure and catalytic mechanism.

    PubMed

    Delvaux, David; Murty, Mamidanna R V S; Gabelica, Valérie; Lakaye, Bernard; Lunin, Vladimir V; Skarina, Tatiana; Onopriyenko, Olena; Kohn, Gregory; Wins, Pierre; De Pauw, Edwin; Bettendorff, Lucien

    2011-09-30

    The CYTH superfamily of proteins is named after its two founding members, the CyaB adenylyl cyclase from Aeromonas hydrophila and the human 25-kDa thiamine triphosphatase. Because these proteins often form a closed β-barrel, they are also referred to as triphosphate tunnel metalloenzymes (TTM). Functionally, they are characterized by their ability to bind triphosphorylated substrates and divalent metal ions. These proteins exist in most organisms and catalyze different reactions depending on their origin. Here we investigate structural and catalytic properties of the recombinant TTM protein from Nitrosomonas europaea (NeuTTM), a 19-kDa protein. Crystallographic data show that it crystallizes as a dimer and that, in contrast to other TTM proteins, it has an open β-barrel structure. We demonstrate that NeuTTM is a highly specific inorganic triphosphatase, hydrolyzing tripolyphosphate (PPP(i)) with high catalytic efficiency in the presence of Mg(2+). These data are supported by native mass spectrometry analysis showing that the enzyme binds PPP(i) (and Mg-PPP(i)) with high affinity (K(d) < 1.5 μm), whereas it has a low affinity for ATP or thiamine triphosphate. In contrast to Aeromonas and Yersinia CyaB proteins, NeuTTM has no adenylyl cyclase activity, but it shares several properties with other enzymes of the CYTH superfamily, e.g. heat stability, alkaline pH optimum, and inhibition by Ca(2+) and Zn(2+) ions. We suggest a catalytic mechanism involving a catalytic dyad formed by Lys-52 and Tyr-28. The present data provide the first characterization of a new type of phosphohydrolase (unrelated to pyrophosphatases or exopolyphosphatases), able to hydrolyze inorganic triphosphate with high specificity.

  6. Growth modelling of Nitrosomonas europaea ATCC® 19718 and Nitrobacter winogradskyi ATCC® 25391: A new online indicator of the partial nitrification.

    PubMed

    Cruvellier, Nelly; Poughon, Laurent; Creuly, Catherine; Dussap, C-Gilles; Lasseur, Christophe

    2016-11-01

    The aim of the present work was to study the growth of two nitrifying bacteria. For modelling the nitrifying subsystem of the MELiSSA loop, Nitrosomonas europaea ATCC® 19718 and Nitrobacter winogradskyi ATCC® 25931 were grown separately and in cocultures. The kinetic parameters of a stoichiometric mass balanced Pirt model were identified: μmax=0.054h(-1), decay rate b=0.003h(-1) and maintenance rate m=0.135gN-NH4(+)·gX(-1)·h(-1) for Nitrosomonas europaea; μmax=0.024h(-1), b=0.001h(-1) and m=0.467gN-NO2(-)·gX(-1)·h(-1) for Nitrobacter winogradskyi. A predictive structured model of nitrification in co-culture was developed. The online evolution of the addition of KOH is correlated to the nitritation; the dissolved oxygen concentration is correlated to both nitritation and nitratation. The model suitably represents these two variables so that transient partial nitrification is assessed. This is a clue for avoiding partial nitrification by predictive functional control.

  7. MeLiSSA third compartment: a kinetic and stoichiometric study for Nitrosomonas europaea and Nitrobacter winogradskyi axenic cultures

    NASA Astrophysics Data System (ADS)

    Creuly, Catherine; Poughon, Laurent; Dussap, Claude-Gilles; Farges, Berangere

    2012-07-01

    As a part of a natural biological N-cycle, nitrification is one of the steps included in the conception of artificial ecosystems designed for extraterrestrial life support systems (LSS). In MELiSSA loop, which is based on carbon and nitrogen recycling, the non-edible part of the higher plants and the waste produced by the crew are collected in the liquefying compartment that degrades the chemically complex wastes into simpler building blocks (organic acids and CO2). The organic acids are eliminated in the second photoheterotrophic compartment letting an organic free medium mostly containing minerals and N-NH+4 nitrogen. The third compartment is in charge to re-oxidize N-NH+4 in order to make nitrogen usable by the following compartments. In MELiSSA, the constraint is to perform axenic cultures in order to fully control the genetic status of the culture and a thorough modelling for developing a control strategy of the compartment and of the loop, knowing that the reliability of the production of oxidized forms of nitrogen NO3- directly impacts the behaviour of the following compartments. Nitrification in aerobic environments is carried out by two groups of bacteria in co-cultures in a two-step process. The ammonia-oxidizing bacteria (Nitrosomonas europaea) realize the oxidation of ammonia to nitrite and the nitrite-oxidizing bacteria (Nitrobacter winogradskyi) the oxidation of nitrite to nitrate. In both cases, the bacteria achieve the oxidations to obtain an energy and reductant source for their growth and maintenance. Both groups use CO2 predominantly as their carbon source. They are typically found together in ecosystems and, consequently, nitrite accumulation is rare. This study concerns kinetic and mass balances studies of axenic cultures of Ns. europaea and Nb. winogradskyi in autotrophic conditions. The daily follow-up of these cultures is done using a new protocol involving flow cytometry and ionic chromatography. Nitrogen substrates and products are

  8. /sup 15/N kinetic analysis of N/sub 2/O production by Nitrosomonas europaea: an examination of nitrifier denitrification

    SciTech Connect

    Poth, M.; Focht, D.D.

    1985-05-01

    A series of /sup 15/N isotope tracer experiments showed that Nitrosomonas europaea produces nitrous oxide only under oxygen-limiting conditions and that the labeled N from nitrite, but not nitrate, is incorporated into nitrous oxide, indicating the presence of the denitrifying enzyme nitrite reductase. A kinetic analysis of the m/z 44, 45, and 46 nitrous oxide produced by washed cell suspensions of N. europaea when incubated with 4 mM ammonium (99% /sup 14/N) and 0.4 mM nitrite (99% /sup 15/N) was performed. No labeled nitirte was reduced to ammonium. All labeled material added was accounted for as either nitrite or nitrous oxide. The hypothesis that nitrous oxide is produced directly from nitrification was rejected since (i) it does not allow for the large amounts of double-labeled (m/z 46) nitrous oxide observed; (ii) the observed patterns of m/z 44, 45, 46 nitrous oxide were completely consistent with a kinetic analysis based on denitrification as the sole mechanism of nitrous oxide production but not with a kinetic analysis based on both mechanisms; (iii) the asymptotic ratio of m/z 45 to m/z 46 nitrous oxide was consistent with denitrification kinetics but inconsistent with nitrification kinetics, which predicted no limit to m/z 45 production. It is concluded that N. europaea is a denitrifier which, under conditions of oxygen stress, uses nitrite as a terminal electron acceptor and produces nitrous oxide.

  9. Linking NE1545 gene expression with cell volume changes in Nitrosomonas europaea cells exposed to aromatic hydrocarbons.

    PubMed

    Radniecki, Tyler S; Gilroy, Caslin A; Semprini, Lewis

    2011-01-01

    Nitrosomonas europaea, a model ammonia oxidizing bacterium, was exposed to a wide variety of aromatic hydrocarbons in 3 h batch assays. The expression of NE1545, a phenol sentinel gene involved in fatty acid metabolism, was monitored via quantitative real-time polymerase chain reaction (qRT-PCR) and a Coulter Counter technique was used to monitor changes in cell volume. Decreases in cell volume and NE1545 gene expression correlated strongly with exposure to aromatic hydrocarbons that possessed a single polar group substitution (e.g. phenol and aniline). Aromatic hydrocarbons that contain no polar group substitutions (e.g. toluene) or multiple polar group substitutions (e.g. p-hydroquinone) caused negligible changes in NE1545 expression and cell volume. The oxidation of aromatic hydrocarbons by N. europaea from configurations without a single polar group to one with two polar groups (e.g. p-cresol oxidized to 4-hydroxybenzyl alcohol) and from configurations with no polar groups to one with a single polar group (e.g. ethylbenzene oxidized to 4-ethylphenol) greatly influenced NE1545 gene expression and observed changes in cell volume. Nitrification inhibition in N. europaea by the aromatic hydrocarbons was found to be completely reversible; however, the decreases in cell volume were not reversible suggesting a physical change in cell membrane composition. Ammonia monooxygenase blocking studies showed that the chemical exposure that was responsible for the cell volume decrease and up-regulation in gene expression and not the observed inhibition. N. europaea is the first bacterium shown to experience significant changes in cell volume when exposed to μM concentrations of aromatic hydrocarbons, three orders of magnitude lower than previous studies with other bacteria.

  10. Characterizing the metabolic trade-off in Nitrosomonas europaea in response to changes in inorganic carbon supply.

    PubMed

    Jiang, D; Khunjar, W O; Wett, B; Murthy, S N; Chandran, K

    2015-02-17

    The link between the nitrogen and one-carbon cycles forms the metabolic basis for energy and biomass synthesis in autotrophic nitrifying organisms, which in turn are crucial players in engineered nitrogen removal processes. To understand how autotrophic nitrifying organisms respond to inorganic carbon (IC) conditions that could be encountered in engineered partially nitrifying systems, we investigated the response of one of the most extensively studied model ammonia oxidizing bacteria, Nitrosomonas europaea (ATCC19718), to three IC availability conditions: excess gaseous and excess ionic IC supply (40× stoichiometric requirement), excess gaseous IC supply (4× stoichiometric requirement in gaseous form only), and limiting IC supply (0.25× stoichiometric requirement). We found that, when switching from excess gaseous and excess ionic IC supply to excess gaseous IC supply, N. europaea chemostat cultures demonstrated an acclimation period that was characterized by transient decreases in the ammonia removal efficiency and transient peaks in the specific oxygen uptake rate. Limiting IC supply led to permanent reactor failures (characterized by biomass washout and failure of ammonia removal) that were preceded by similar decreases in the ammonia removal efficiency and peaks in the specific oxygen uptake rate. Notably, both excess gaseous IC supply and limiting IC supply elicited a previously undocumented increase in nitric and nitrous oxide emissions. Further, gene expression patterns suggested that excess gaseous IC supply and limiting IC supply led to consistent up-regulation of ammonia respiration genes and carbon assimilation genes. Under these conditions, interrogation of the N. europaea proteome revealed increased levels of carbon fixation and transport proteins and decreased levels of ammonia oxidation proteins (active in energy synthesis pathways). Together, the results indicated that N. europaea mobilized enhanced IC scavenging pathways for biosynthesis and

  11. Revision of N2O-producing pathways in the ammonia-oxidizing bacterium Nitrosomonas europaea ATCC 19718.

    PubMed

    Kozlowski, Jessica A; Price, Jennifer; Stein, Lisa Y

    2014-08-01

    Nitrite reductase (NirK) and nitric oxide reductase (NorB) have long been thought to play an essential role in nitrous oxide (N2O) production by ammonia-oxidizing bacteria. However, essential gaps remain in our understanding of how and when NirK and NorB are active and functional, putting into question their precise roles in N2O production by ammonia oxidizers. The growth phenotypes of the Nitrosomonas europaea ATCC 19718 wild-type and mutant strains deficient in expression of NirK, NorB, and both gene products were compared under atmospheric and reduced O2 tensions. Anoxic resting-cell assays and instantaneous nitrite (NO2 (-)) reduction experiments were done to assess the ability of the wild-type and mutant N. europaea strains to produce N2O through the nitrifier denitrification pathway. Results confirmed the role of NirK for efficient substrate oxidation of N. europaea and showed that NorB is involved in N2O production during growth at both atmospheric and reduced O2 tensions. Anoxic resting-cell assays and measurements of instantaneous NO2 (-) reduction using hydrazine as an electron donor revealed that an alternate nitrite reductase to NirK is present and active. These experiments also clearly demonstrated that NorB was the sole nitric oxide reductase for nitrifier denitrification. The results of this study expand the enzymology for nitrogen metabolism and N2O production by N. europaea and will be useful to interpret pathways in other ammonia oxidizers that lack NirK and/or NorB genes.

  12. L-Malate dehydrogenase activity in the reductive arm of the incomplete citric acid cycle of Nitrosomonas europaea.

    PubMed

    Deutch, Charles E

    2013-11-01

    The autotrophic nitrifying bacterium Nitrosomonas europaea does not synthesize 2-oxoglutarate (α-ketoglutarate) dehydrogenase under aerobic conditions and so has an incomplete citric acid cycle. L-malate (S-malate) dehydrogenase (MDH) from N. europaea was predicted to show similarity to the NADP(+)-dependent enzymes from chloroplasts and was separated from the NAD(+)-dependent proteins from most other bacteria or mitochondria. MDH activity in a soluble fraction from N. europaea ATCC 19718 was measured spectrophotometrically and exhibited simple Michaelis-Menten kinetics. In the reductive direction, activity with NADH increased from pH 6.0 to 8.5 but activity with NADPH was consistently lower and decreased with pH. At pH 7.0, the K m for oxaloacetate was 20 μM; the K m for NADH was 22 μM but that for NADPH was at least 10 times higher. In the oxidative direction, activity with NAD(+) increased with pH but there was very little activity with NADP(+). At pH 7.0, the K m for L-malate was 5 mM and the K m for NAD(+) was 24 μM. The reductive activity was quite insensitive to inhibition by L-malate but the oxidative activity was very sensitive to oxaloacetate. MDH activity was not strongly activated or inhibited by glycolytic or citric acid cycle metabolites, adenine nucleotides, NaCl concentrations, or most metal ions, but increased with temperature up to about 55 °C. The reductive activity was consistently 10-20 times higher than the oxidative activity. These results indicate that the L-malate dehydrogenase in N. europaea is similar to other NAD(+)-dependent MDHs (EC 1.1.1.37) but physiologically adapted for its role in a reductive biosynthetic sequence.

  13. Revision of N2O-Producing Pathways in the Ammonia-Oxidizing Bacterium Nitrosomonas europaea ATCC 19718

    PubMed Central

    Kozlowski, Jessica A.; Price, Jennifer

    2014-01-01

    Nitrite reductase (NirK) and nitric oxide reductase (NorB) have long been thought to play an essential role in nitrous oxide (N2O) production by ammonia-oxidizing bacteria. However, essential gaps remain in our understanding of how and when NirK and NorB are active and functional, putting into question their precise roles in N2O production by ammonia oxidizers. The growth phenotypes of the Nitrosomonas europaea ATCC 19718 wild-type and mutant strains deficient in expression of NirK, NorB, and both gene products were compared under atmospheric and reduced O2 tensions. Anoxic resting-cell assays and instantaneous nitrite (NO2−) reduction experiments were done to assess the ability of the wild-type and mutant N. europaea strains to produce N2O through the nitrifier denitrification pathway. Results confirmed the role of NirK for efficient substrate oxidation of N. europaea and showed that NorB is involved in N2O production during growth at both atmospheric and reduced O2 tensions. Anoxic resting-cell assays and measurements of instantaneous NO2− reduction using hydrazine as an electron donor revealed that an alternate nitrite reductase to NirK is present and active. These experiments also clearly demonstrated that NorB was the sole nitric oxide reductase for nitrifier denitrification. The results of this study expand the enzymology for nitrogen metabolism and N2O production by N. europaea and will be useful to interpret pathways in other ammonia oxidizers that lack NirK and/or NorB genes. PMID:24907318

  14. Clarifying the regulation of NO/N2O production in Nitrosomonas europaea during anoxic-oxic transition via flux balance analysis of a metabolic network model.

    PubMed

    Perez-Garcia, Octavio; Villas-Boas, Silas G; Swift, Simon; Chandran, Kartik; Singhal, Naresh

    2014-09-01

    The metabolic mechanism regulating the production of nitric and nitrous oxide (NO, N2O) in ammonia oxidizing bacteria (AOB) was characterized by flux balance analysis (FBA) of a stoichiometric metabolic network (SMN) model. The SMN model was created using 51 reactions and 44 metabolites of the energy metabolism in Nitrosomonas europaea, a widely studied AOB. FBA of model simulations provided estimates for reaction rates and yield ratios of intermediate metabolites, substrates, and products. These estimates matched well, deviating on average by 15% from values for 17 M yield ratios reported for non-limiting oxygen and ammonium concentrations. A sensitivity analysis indicated that the reactions catalysed by cytochromes aa3 and P460 principally regulate the pathways of NO and N2O production (hydroxylamine oxidoreductase mediated and nitrifier denitrification). FBA of simulated N. europaea exposure to oxic-anoxic-oxic transition indicated that NO and N2O production primarily resulted from an intracellular imbalance between the production and consumption of electron equivalents during NH3 oxidation, and that NO and N2O are emitted when the sum of their production rates is greater than half the rate of NO oxidation by cytochrome P460.

  15. Crystallization and preliminary X-ray crystallographic analysis of a new crystal form of hydroxylamine oxidoreductase from Nitrosomonas europaea.

    PubMed

    Cedervall, Peder E; Hooper, Alan B; Wilmot, Carrie M

    2009-12-01

    Hydroxylamine oxidoreductase (HAO) from Nitrosomonas europaea is a homotrimeric protein that catalyzes the oxidation of hydroxylamine to nitrite. Each monomer, with a molecular weight of 67.1 kDa, contains seven c-type hemes and one heme P460, the porphyrin ring of which is covalently linked to a tyrosine residue from an adjacent subunit. HAO was first crystallized and structurally characterized at a resolution of 2.8 A in 1997. The structure was solved in space group P6(3) and suffered from merohedral twinning. Here, a crystallization procedure is presented that yielded untwinned crystals belonging to space group P2(1)2(1)2, which diffracted to 2.25 A resolution and contained one trimer in the asymmetric unit. The unit-cell parameters were a = 140.7, b = 142.6, c = 107.4 A.

  16. The influence of Corexit 9500A and weathering on Alaska North Slope crude oil toxicity to the ammonia oxidizing bacterium, Nitrosomonas europaea.

    PubMed

    Radniecki, Tyler S; Schneider, Margaret C; Semprini, Lewis

    2013-03-15

    The toxicity of the water associated fraction (WAF) of Alaska North Slope Crude oil (ANSC), Corexit 9500A and the dispersant enhanced WAF (DEWAF) of ANSC:Corexit 9500A mixtures were examined on the model ammonia oxidizing bacterium, Nitrosomonas europaea. Corexit 9500A was not toxic at environmentally relevant concentrations. Corexit 9500A greatly increased the toxicity of ANSC by increasing the chemical oxygen demand (COD) of the DEWAF. However, a majority of the DEWAF compounds were not toxic to N. europaea. Weathered WAF and DEWAF were not toxic to N. europaea even though their COD did not change compared to non-weathered controls, suggesting that toxicity was due to a small volatile fraction of the ANSC. The over-expression of the NE1545 gene, a marker for aromatic hydrocarbon exposure, in N. europaea cells exposed to WAF and DEWAF suggests that aromatic hydrocarbons are bioavailable to the cells and may play a role in the observed toxicity.

  17. Whole-genome transcriptional and physiological responses of Nitrosomonas europaea to cyanide: identification of cyanide stress response genes.

    PubMed

    Park, Sunhwa; Ely, Roger L

    2009-04-15

    Nitrosomonas europaea (ATCC 19718) is one of several nitrifying species that participate in the biological removal of nitrogen from wastewater by oxidizing ammonia to nitrite, the first step in nitrification. Because nitrification is quite sensitive to cyanide, a compound often encountered in wastewater treatment plants, we characterized the physiological and transcriptional responses of N. europaea cells to cyanide. The cells were extremely sensitive to low concentrations of cyanide, with NO-(2)production and ammonia-dependent oxygen uptake rates decreasing by 50% within 30 min of exposure to 1 microM NaCN. Whole-genome transcriptional responses of cells exposed to 1 microM NaCN were examined using Affymetrix microarrays to identify stress-induced genes. The transcript levels of 35 genes increased more than 2-fold while transcript levels of 29 genes decreased more than 20-fold. A gene cluster that included moeZ (NE2353), encoding a rhodanese homologue and thought to be involved in detoxification of cyanide, showed the highest up-regulation (7-fold). The down-regulated genes included genes encoding proteins involved in the sulfate reduction pathway, signal transduction mechanisms, carbohydrate transport, energy production, coenzyme metabolism, and amino acid transport.

  18. Testing Silver Nanoparticle Toxicity Using the Ammonia Oxidizing Bacteria Nitrosomonas Europaea and a High-throughput Assay

    NASA Astrophysics Data System (ADS)

    Semprini, L.; Bartow, S.; Radniecki, T.

    2012-04-01

    Understanding the toxicity of nanoparticles on ecologically significant wastewater microbiota, specifically ammonia oxidizing bacteria (AOB), is critical due to the exponential increase in commercialization of nanoparticles as well as the sensitivity of AOB to inhibitors. A high-throughput activity assay was developed to rapidly screen for nanoparticle toxicity on AOB, using a multi-well plate method and AOB Nitrosomonas Europaea. This method demonstrated good agreement with previously established batch bottle assays utilizing both silver ions (Ag+) and nanoparticles (Ag-NPs) as nitrification inhibitors. The method was used to study the inhibition of Ag+ and Ag-NPs (20 nm) on the nitrification by N. Europaea cells grown in fill-and-draw reactors compared exponentially grown batch cells. Results indicate longer hydraulic residence times increased some protection against inhibition as measured by the production of nitrite over a three hour assay. The cells were more sensitive to Ag+ than Ag-NP, which is consistent with our past observations. Studies are currently being conducted to determine the effects that the presence of humic acid and cations on the inhibition and toxicity. Our initial results show that the presence of Mg++ provides protect from Ag-NP inhibition, which partly results from the aggregation of the Ag-NP and a decrease in the rate of oxidation of the Ag-NP to Ag+. The presence of humic acid also provides for some protection from Ag-NP inhibition.

  19. Expression, purification, crystallization and preliminary X-ray diffraction of a novel Nitrosomonas europaea cytochrome, cytochrome P460

    SciTech Connect

    Elmore, Bradley O.; Pearson, Arwen R.; Wilmot, Carrie M.; Hooper, Alan B.

    2006-04-01

    Cytochrome P460 from N. europaea, a novel mono-heme protein containing an unusual lysine cross-link to the porphyrin ring, has been recombinantly expressed and purified from E. coli and crystallized. The crystals belong to the trigonal space group P3{sub 1/2}21, with unit-cell parameters a = b = 53.3, c = 127.1 Å, one monomer in the asymmetric unit and diffract to 1.7 Å on a Cu Kα rotating-anode X-ray source. Cytochrome P460 from Nitrosomonas europaea, a novel mono-heme protein containing an unusual cross-link between a conserved lysine and the porphyrin ring, has been recombinantly expressed and purified from Escherichia coli. The protein crystallizes readily and diffraction to 1.7 Å has been obtained in-house. The crystals belong to the trigonal space group P3{sub 1/2}21, with unit-cell parameters a = b = 53.3, c = 127.1 Å, and contain one monomer in the asymmetric unit.

  20. Denitrification and ammonia oxidation by Nitrosomonas europaea wild-type, and NirK- and NorB-deficient mutants.

    PubMed

    Schmidt, Ingo; van Spanning, Rob J M; Jetten, Mike S M

    2004-12-01

    The phenotypes of three different Nitrosomonas europaea strains--wild-type, nitrite reductase (NirK)-deficient and nitric oxide reductase (NorB)-deficient strains--were characterized in chemostat cell cultures, and the effect of nitric oxide (NO) on metabolic activities was evaluated. All strains revealed similar aerobic ammonia oxidation activities, but the growth rates and yields of the knock-out mutants were significantly reduced. Dinitrogen (N2) was the main gaseous product of the wild-type, produced via its denitrification activity. The mutants were unable to reduce nitrite to N2, but excreted more hydroxylamine leading to the formation of almost equal amounts of NO, nitrous oxide (N2O) and N2 by chemical auto-oxidation and chemodenitrification of hydroxylamine. Under anoxic conditions Nsm. europaea wild-type gains energy for growth via nitrogen dioxide (NO2)-dependent ammonia oxidation or hydrogen-dependent denitrification using nitrite as electron acceptor. The mutant strains were restricted to NO and/or N2O as electron acceptor and consequently their growth rates and yields were much lower compared with the wild-type. When cells were transferred from anoxic (denitrification) to oxic conditions, the wild-type strain endogenously produced NO and recovered ammonia oxidation within 8 h. In contrast, the mutant strains remained inactive. For recovery of ammonia oxidation activity the NO concentration had to be adjusted to about 10 p.p.m. in the aeration gas.

  1. Silver nanoparticles temporarily retard NO2 - production without significantly affecting N2 O release by Nitrosomonas europaea.

    PubMed

    Michels, Camila; Yang, Yu; Moreira Soares, Hugo; Alvarez, Pedro J J

    2015-10-01

    Nitrifying bacteria are highly susceptible to silver nanoparticles (AgNPs). However, the effect of sublethal exposure to AgNPs after their release of nitrogenous compounds of environmental concern (e.g., the greenhouse gas nitrous oxide [N2 O] and the common water pollutant nitrite [NO2 -]) has not been systematically investigated. The present study reports the effect of AgNPs (and potentially released silver ions [Ag(+) ]) on NO2 - and N2 O production by Nitrosomonas europaea, and on the transcription of the associated genes. The release of NO2 - was more negatively affected than the production of N2 O. For example, exposure to AgNPs at 0.075 mg/L temporarily enhanced N2 O production (by 12%) without affecting nitrite release, whereas higher AgNP concentrations (>0.25 mg/L) inhibited NO2 - release (by >12%) but not N2 O production. Transcriptomic analyses corroborated these trends; AgNPs at 0.075 mg/L increased the expression of the nitric oxide reductase gene (norQ) associated with N2 O production (by 5.3-fold to 12.8-fold), whereas both 0.075 mg/L of Ag(+) and 0.75 mg/L of AgNPs down-regulated the ammonia monooxygenase gene (amoA2; by 0.08-fold to 0.15-fold and 0.32-fold to 0.64-fold, respectively), the nitrite reductase gene (nirK; by 0.01-fold to 0.02-fold and 0.22-fold to 0.44-fold, respectively), and norQ (by 0.11-fold to 0.15-fold and 0.32-fold to 0.57-fold, respectively). These results suggest that AgNP release to sewage treatment plants and land application of AgNP-containing biosolids should be minimized because of their potential temporary stimulation of N2 O release and interference with nitrification. Environ Toxicol Chem 2015;34:2231-2235. © 2015 SETAC.

  2. Inhibition of phenol on the rates of ammonia oxidation by Nitrosomonas europaea grown under batch, continuous fed, and biofilm conditions.

    PubMed

    Lauchnor, Ellen G; Semprini, Lewis

    2013-09-01

    Ammonia oxidation by Nitrosomonas europaea, an ammonia oxidizing bacterium prevalent in wastewater treatment, is inhibited in the presence of phenol, due to interaction of the phenol with the ammonia monooxygenase enzyme. Suspended cells of N. europaea were cultured in batch reactors and continuous flow reactors at dilution rates of 0.01-0.2 d(-1). The rate of ammonia oxidation in the continuous cultures correlated to the dilution rate in the reactor. The batch and continuous cultures were exposed to 20 μM phenol and ammonia oxidation activity was measured by specific oxygen uptake rates (SOURs). Inhibition of NH3 oxidation by 20 μM phenol ranged from a 77% reduction of SOUR observed with suspended cells harvested during exponential growth, to 26% in biofilms. The extent of inhibition was correlated with ammonia oxidation rates in both suspended and biofilm cells, with greater percent inhibition observed with higher initial rates of NH3 oxidation. In biofilm grown cells, an increase in activity and phenol inhibition were both observed upon dispersing the biofilm cells into fresh, liquid medium. Under higher oxygen tension, an increase in the NO2(-) production of the biofilms was observed and biofilms were more susceptible to phenol inhibition. Dissolved oxygen microsensor measurements showed oxygen limited conditions existed in the biofilms. The ammonia oxidation rate was much lower in biofilms, which were less inhibited during phenol exposure. The results clearly indicate in both suspended and attached cells of N. europaea that a higher extent of phenol inhibition is positively correlated with a higher rate of NH3 oxidation (enzyme turnover).

  3. Physiological state, growth mode, and oxidative stress play a role in Cd(II)-mediated inhibition of Nitrosomonas europaea 19718.

    PubMed

    Chandran, Kartik; Love, Nancy G

    2008-04-01

    The goal of this study was to determine the impact of physiological growth states (batch exponential and batch stationary growth) and growth modes (substrate-limited chemostat, substrate-sufficient exponential batch, and substrate-depleted stationary batch growth) on several measures of growth and responses to Cd(II)-mediated inhibition of Nitrosomonas europaea strain 19718. The specific oxygen uptake rate (sOUR) was the most sensitive indicator of inhibition among the different responses analyzed, including total cell abundance, membrane integrity, intracellular 16S rRNA/DNA ratio, and amoA expression. This observation remained true irrespective of the physiological state, the growth mode, or the mode of Cd(II) exposure. Based on the sOUR, a strong time-dependent exacerbation of inhibition (in terms of an inhibition coefficient [K(i)]) in exponential batch cultures was observed. Long-term inhibition levels (based on K(i) estimates) in metabolically active chemostat and exponential batch cultures were also especially severe and comparable. In contrast, the inhibition level in stationary-phase cultures was 10-fold lower and invariable with exposure time. Different strategies for surviving substrate limitation (a 10-fold increase in amoA expression) and starvation (the retention of 16S rRNA levels) in N. europaea cultures were observed. amoA expression was most negatively impacted by Cd(II) exposure in the chemostat cultures, was less impacted in exponential batch cultures, and was least impacted in stationary batch cultures. Although the amoA response was consistent with that of the sOUR, the amoA response was not as strong. The intracellular 16S rRNA/DNA ratio, as determined by fluorescence in situ hybridization, also did not uniformly correlate with the sOUR under conditions of inhibition or no inhibition. Finally, Cd(II)-mediated inhibition of N. europaea was attributed partially to oxidative stress.

  4. Distribution of Nitrosomonas europaea and Nitrobacter winogradskyi in an autotrophic nitrifying biofilm reactor as depicted by molecular analyses and mathematical modelling.

    PubMed

    Montràs, Anna; Pycke, Benny; Boon, Nico; Gòdia, Francesc; Mergeay, Max; Hendrickx, Larissa; Pérez, Julio

    2008-03-01

    The autotrophic two-species biofilm from the packed bed reactor of a life-support system, containing Nitrosomonas europaea ATCC 19718 and Nitrobacter winogradskyi ATCC 25391, was analysed after 4.8 years of continuous operation performing complete nitrification. Real-time quantitative polymerase chain reaction (Q-PCR) was used to quantify N. europaea and N. winogradskyi along the vertical axis of the reactor, revealing a spatial segregation of N. europaea and N. winogradskyi. The main parameters influencing the spatial segregation of both nitrifiers along the bed were assessed through a multi-species one-dimensional biofilm model generated with AQUASIM software. The factor that contributed the most to this distribution profile was a small deviation from the flow pattern of a perfectly mixed tank towards plug-flow. The results indicate that the model can estimate the impact of specific biofilm parameters and predict the nitrification efficiency and population dynamics of a multispecies biofilm.

  5. A rapid and simple respirometric biosensor with immobilized cells of Nitrosomonas europaea for detecting inhibitors of ammonia oxidation.

    PubMed

    Cui, Rong; Chung, Wook-Jin; Jahng, Deokjin

    2005-03-15

    As obligate chemolithotrophs, ammonia-oxidizing bacteria (AOB) grow very slowly and are known to be extremely sensitive to a wide variety of inhibitors. Since it is generally accepted that inhibition of ammonia oxidation by AOB results in a total failure of nitrogen removal, it is necessary to develop a method to detect inhibitors of ammonia oxidation in wastewater. Since ammonia oxidation accompanies oxygen consumption, ammonia oxidation can be easily evaluated by measuring oxygen consumption rate using a dissolved oxygen (DO) probe. In this study, a rapid and simple respirometric biosensor using the pure culture of Nitrosomonas europaea was developed. N. europaea was cultivated in a continuous fermentor operating at the dilution rate of 0.008 h(-1) to obtain physiologically constant cells and was immobilized onto the dialysis membrane through filtration. DO, determined by the biosensor, started to increase 30 s later after ammonia oxidation inhibitor was fed, and a new steady-state DO was obtained in 10-30 min. For this DO profile, steady-state kinetics was applied to evaluate ammonia oxidation efficiency. The concentration of a toxic compound causing 50% decrease of oxygen-consumption activity (EC50) was determined for different chemicals. The EC50 values obtained with the biosensor (0.018 mg l(-1) for allylthiourea, 0.027 mg l(-1) for thioacetamide, 1.10 mg l(-1) for phenol and 0.0 1mg l(-1) for thiourea) indicated that the developed biosensor was highly sensitive to a variety of the inhibitors. It was also shown that the biosensor is applicable for on-line real time monitoring.

  6. Transcription of all amoC copies is associated with recovery of Nitrosomonas europaea from ammonia starvation.

    PubMed

    Berube, Paul M; Samudrala, Ram; Stahl, David A

    2007-06-01

    The chemolithotrophic ammonia-oxidizing bacterium Nitrosomonas europaea is known to be highly resistant to starvation conditions. The transcriptional response of N. europaea to ammonia addition following short- and long-term starvation was examined by primer extension and S1 nuclease protection analyses of genes encoding enzymes for ammonia oxidation (amoCAB operons) and CO(2) fixation (cbbLS), a third, lone copy of amoC (amoC(3)), and two representative housekeeping genes (glyA and rpsJ). Primer extension analysis of RNA isolated from growing, starved, and recovering cells revealed two differentially regulated promoters upstream of the two amoCAB operons. The distal sigma(70) type amoCAB promoter was constitutively active in the presence of ammonia, but the proximal promoter was only active when cells were recovering from ammonia starvation. The lone, divergent copy of amoC (amoC(3)) was expressed only during recovery. Both the proximal amoC(1,2) promoter and the amoC(3) promoter are similar to gram-negative sigma(E) promoters, thus implicating sigma(E) in the regulation of the recovery response. Although modeling of subunit interactions suggested that a nonconservative proline substitution in AmoC(3) may modify the activity of the holoenzyme, characterization of a DeltaamoC(3) strain showed no significant difference in starvation recovery under conditions evaluated. In contrast to the amo transcripts, a delayed appearance of transcripts for a gene required for CO(2) fixation (cbbL) suggested that its transcription is retarded until sufficient energy is available. Overall, these data revealed a programmed exit from starvation likely involving regulation by sigma(E) and the coordinated regulation of catabolic and anabolic genes.

  7. Transcription of All amoC Copies Is Associated with Recovery of Nitrosomonas europaea from Ammonia Starvation▿

    PubMed Central

    Berube, Paul M.; Samudrala, Ram; Stahl, David A.

    2007-01-01

    The chemolithotrophic ammonia-oxidizing bacterium Nitrosomonas europaea is known to be highly resistant to starvation conditions. The transcriptional response of N. europaea to ammonia addition following short- and long-term starvation was examined by primer extension and S1 nuclease protection analyses of genes encoding enzymes for ammonia oxidation (amoCAB operons) and CO2 fixation (cbbLS), a third, lone copy of amoC (amoC3), and two representative housekeeping genes (glyA and rpsJ). Primer extension analysis of RNA isolated from growing, starved, and recovering cells revealed two differentially regulated promoters upstream of the two amoCAB operons. The distal σ70 type amoCAB promoter was constitutively active in the presence of ammonia, but the proximal promoter was only active when cells were recovering from ammonia starvation. The lone, divergent copy of amoC (amoC3) was expressed only during recovery. Both the proximal amoC1,2 promoter and the amoC3 promoter are similar to gram-negative σE promoters, thus implicating σE in the regulation of the recovery response. Although modeling of subunit interactions suggested that a nonconservative proline substitution in AmoC3 may modify the activity of the holoenzyme, characterization of a ΔamoC3 strain showed no significant difference in starvation recovery under conditions evaluated. In contrast to the amo transcripts, a delayed appearance of transcripts for a gene required for CO2 fixation (cbbL) suggested that its transcription is retarded until sufficient energy is available. Overall, these data revealed a programmed exit from starvation likely involving regulation by σE and the coordinated regulation of catabolic and anabolic genes. PMID:17384196

  8. Steady-State Growth under Inorganic Carbon Limitation Conditions Increases Energy Consumption for Maintenance and Enhances Nitrous Oxide Production in Nitrosomonas europaea

    PubMed Central

    Giguere, Andrew; Chaplen, Frank; Bottomley, Peter J.

    2016-01-01

    on ammonia-oxidizing microorganisms and nitrite-oxidizing bacteria. Most nitrifiers are chemolithoautotrophs that fix inorganic carbon (CO2) for growth. Here, we investigate how inorganic carbon limitation modifies the physiology and transcriptome of Nitrosomonas europaea, a model ammonia-oxidizing bacterium, and report on increased production of N2O, a potent greenhouse gas. This study, along with previous work, suggests that inorganic carbon limitation may be an important factor in controlling N2O emissions from nitrification in soils and wastewater treatment. PMID:27016565

  9. New Insights into Methyl Bromide Cooxidation by Nitrosomonas europaea Obtained by Experimenting with Moderately Low Density Cell Suspensions†

    PubMed Central

    Duddleston, Khrystyne N.; Bottomley, Peter J.; Porter, Angela J.; Arp, Daniel J.

    2000-01-01

    We examined the rates and sustainability of methyl bromide (MeBr) oxidation in moderately low density cell suspensions (∼6 × 107 cells ml−1) of the NH3-oxidizing bacterium Nitrosomonas europaea. In the presence of 10 mM NH4+ and 0.44, 0.22, and 0.11 mM MeBr, the initial rates of MeBr oxidation were sustained for 12, 12, and 24 h, respectively, despite the fact that only 10% of the NH4+, 18% of the NH4+, and 35% of the NH4+, respectively, were consumed. Although the duration of active MeBr oxidation generally decreased as the MeBr concentration increased, similar amounts of MeBr were oxidized with a large number of the NH4+-MeBr combinations examined (10 to 20 μmol mg [dry weight] of cells−1). Approximately 90% of the NH3-dependent O2 uptake activity and the NO2−-producing activity were lost after N. europaea was exposed to 0.44 mM MeBr for 24 h. After MeBr was removed and the cells were resuspended in fresh growth medium, NO2− production increased exponentially, and 48 to 60 h was required to reach the level of activity observed initially in control cells that were not exposed to MeBr. It is not clear what percentage of the cells were capable of cell division after MeBr oxidation because NO2− accumulated more slowly in the exposed cells than in the unexposed cells despite the fact that the latter were diluted 10-fold to create inocula which exhibited equal initial activities. The decreases in NO2−-producing and MeBr-oxidizing activities could not be attributed directly to NH4+ or NH3 limitation, to a decrease in the pH, to the composition of the incubation medium, or to toxic effects caused by accumulation of the end products of oxidation (NO2− and formaldehyde) in the medium. Additional cooxidation-related studies of N. europaea are needed to identify the mechanism(s) responsible for the MeBr-induced loss of cell activity and/or viability, to determine what percentages of cells damaged by cooxidative activities are culturable, and to determine if

  10. Expression and purification of recombinant proteins in Escherichia coli tagged with a small metal-binding protein from Nitrosomonas europaea.

    PubMed

    Vargas-Cortez, Teresa; Morones-Ramirez, Jose Ruben; Balderas-Renteria, Isaias; Zarate, Xristo

    2016-02-01

    Escherichia coli is still the preferred organism for large-scale production of recombinant proteins. The use of fusion proteins has helped considerably in enhancing the solubility of heterologous proteins and their purification with affinity chromatography. Here, the use of a small metal-binding protein (SmbP) from Nitrosomonas europaea is described as a new fusion protein for protein expression and purification in E. coli. Fluorescent proteins tagged at the N-terminal with SmbP showed high levels of solubility, compared with those of maltose-binding protein and glutathione S-transferase, and low formation of inclusion bodies. Using commercially available IMAC resins charged with Ni(II), highly pure recombinant proteins were obtained after just one chromatography step. Proteins may be purified from the periplasm of E. coli if SmbP contains the signal sequence at the N-terminal. After removal of the SmbP tag from the protein of interest, high-yields are obtained since SmbP is a protein of just 9.9 kDa. The results here obtained suggest that SmbP is a good alternative as a fusion protein/affinity tag for the production of soluble recombinant proteins in E. coli.

  11. Application of an integrated statistical design for optimization of culture condition for ammonium removal by Nitrosomonas europaea.

    PubMed

    Bao, Yingling; Zhengfang, Ye

    2013-01-01

    Statistical methodology was applied to the optimization of the ammonium oxidation by Nitrosomonas europaea for biomass concentration (C(B)), nitrite yield (Y(N)) and ammonium removal (R(A)). Initial screening by Plackett-Burman design was performed to select major variables out of nineteen factors, among which NH4Cl concentration (C(N)), trace element solution (TES), agitation speed (AS), and fermentation time (T) were found to have significant effects. Path of steepest ascent and response surface methodology was applied to optimize the levels of the selected factors. Finally, multi-objective optimization was used to obtain optimal condition by compromise of the three desirable objectives through a combination of weighted coefficient method coupled with entropy measurement methodology. These models enabled us to identify the optimum operation conditions (C(N)= 84.1 mM; TES = 0.74 ml; AS= 100 rpm and T = 78 h), under which C(B)= 3.386×10(8) cells/ml; Y(N)= 1.98 mg/mg and R(A) = 97.76% were simultaneously obtained. The optimized conditions were shown to be feasible through verification tests.

  12. Application of an Integrated Statistical Design for Optimization of Culture Condition for Ammonium Removal by Nitrosomonas europaea

    PubMed Central

    yingling, Bao; zhengfang, Ye

    2013-01-01

    Statistical methodology was applied to the optimization of the ammonium oxidation by Nitrosomonas europaea for biomass concentration (CB), nitrite yield (YN) and ammonium removal (RA). Initial screening by Plackett-Burman design was performed to select major variables out of nineteen factors, among which NH4Cl concentration (CN), trace element solution (TES), agitation speed (AS), and fermentation time (T) were found to have significant effects. Path of steepest ascent and response surface methodology was applied to optimize the levels of the selected factors. Finally, multi-objective optimization was used to obtain optimal condition by compromise of the three desirable objectives through a combination of weighted coefficient method coupled with entropy measurement methodology. These models enabled us to identify the optimum operation conditions (CN = 84.1 mM; TES = 0.74 ml; AS = 100 rpm and T = 78 h), under which CB = 3.386×108 cells/ml; YN = 1.98 mg/mg and RA = 97.76% were simultaneously obtained. The optimized conditions were shown to be feasible through verification tests. PMID:23565225

  13. Disruption of sucA, which encodes the E1 subunit of alpha-ketoglutarate dehydrogenase, affects the survival of Nitrosomonas europaea in stationary phase.

    PubMed

    Hommes, Norman G; Kurth, Elizabeth G; Sayavedra-Soto, Luis A; Arp, Daniel J

    2006-01-01

    Although Nitrosomonas europaea lacks measurable alpha-ketoglutarate dehydrogenase activity, the recent completion of the genome sequence revealed the presence of the genes encoding the enzyme. A knockout mutation was created in the sucA gene encoding the E1 subunit. Compared to wild-type cells, the mutant strain showed an accelerated loss of ammonia monooxygenase and hydroxylamine oxidoreductase activities upon entering stationary phase. In addition, unlike wild-type cells, the mutant strain showed a marked lag in the ability to resume growth in response to pH adjustments in late stationary phase.

  14. Membrane tetraheme cytochrome c(m552) of the ammonia-oxidizing nitrosomonas europaea: a ubiquinone reductase.

    PubMed

    Kim, Hyung J; Zatsman, Anna; Upadhyay, Anup K; Whittaker, Mark; Bergmann, David; Hendrich, Michael P; Hooper, Alan B

    2008-06-24

    Cytochrome c(m552) (cyt c(m552)) from the ammonia-oxidizing Nitrosomonas europaea is encoded by the cycB gene, which is preceded in a gene cluster by three genes encoding proteins involved in the oxidation of hydroxylamine: hao, hydroxylamine oxidoreductase; orf2, a putative membrane protein; cycA, cyt c(554). By amino acid sequence alignment of the core tetraheme domain, cyt c(m552) belongs to the NapC/TorC family of tetra- or pentaheme cytochrome c species involved in electron transport from membrane quinols to a variety of periplasmic electron shuttles leading to terminal reductases. However, cyt c(m552) is thought to reduce quinone with electrons originating from HAO. In this work, the tetrahemic 27 kDa cyt c(m552) from N. europaea was purified after extraction from membranes using Triton X-100 with subsequent exchange into n-dodecyl beta-d-maltoside. The cytochrome had a propensity to form strong SDS-resistant dimers likely mediated by a conserved GXXXG motif present in the putative transmembrane segment. Optical spectra of the ferric protein contained a broad ligand-metal charge transfer band at approximately 625 nm indicative of a high-spin heme. Mossbauer spectroscopy of the reduced (57)Fe-enriched protein revealed the presence of high-spin and low-spin hemes in a 1:3 ratio. Multimode EPR spectroscopy of the native state showed signals from an electronically interacting high-spin/low-spin pair of hemes. Upon partial reduction, a typical high-spin heme EPR signal was observed. No EPR signals were observed from the other two low-spin hemes, indicating an electronic interaction between these hemes as well. UV-vis absorption data indicate that CO (ferrous enzyme) or CN(-) (ferric or ferrous enzyme) bound to more than one and possibly all hemes. Other anionic ligands did not bind. The four ferrous hemes of the cytochrome were rapidly oxidized in the presence of oxygen. Comparative modeling, based on the crystal structure and conserved residues of the homologous

  15. A comparison of NO and N2O production by the autotrophic nitrifier Nitrosomonas europaea and the heterotrophic nitrifier Alcaligenes faecalis.

    PubMed Central

    Anderson, I C; Poth, M; Homstead, J; Burdige, D

    1993-01-01

    Soil microorganisms are important sources of the nitrogen trace gases NO and N2O for the atmosphere. Present evidence suggests that autotrophic nitrifiers such as Nitrosomonas europaea are the primary producers of NO and N2O in aerobic soils, whereas denitrifiers such as Pseudomonas spp. or Alcaligenes spp. are responsible for most of the NO and N2O emissions from anaerobic soils. It has been shown that Alcaligenes faecalis, a bacterium common in both soil and water, is capable of concomitant heterotrophic nitrification and denitrification. This study was undertaken to determine whether heterotrophic nitrification might be as important a source of NO and N2O as autotrophic nitrification. We compared the responses of N. europaea and A. faecalis to changes in partial O2 pressure (pO2) and to the presence of typical nitrification inhibitors. Maximal production of NO and N2O occurred at low pO2 values in cultures of both N. europaea (pO2, 0.3 kPa) and A. faecalis (pO2, 2 to 4 kPa). With N. europaea most of the NH4+ oxidized was converted to NO2-, with NO and N2O accounting for 2.6 and 1% of the end product, respectively. With A. faecalis maximal production of NO occurred at a pO2 of 2 kPa, and maximal production of N2O occurred at a pO2 of 4 kPa. At these low pO2 values there was net nitrite consumption. Aerobically, A. faecalis produced approximately the same amount of NO but 10-fold more N2O per cell than N. europaea did. Typical nitrification inhibitors were far less effective for reducing emissions of NO and N2O by A. faecalis than for reducing emissions of NO and N2O by N. europaea.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8285659

  16. Physiological and transcriptional responses of Nitrosomonas europaea to TiO2 and ZnO nanoparticles and their mixtures.

    PubMed

    Yu, Ran; Wu, Junkang; Liu, Meiting; Chen, Lianghui; Zhu, Guangcan; Lu, Huijie

    2016-07-01

    The short-term combined effects of two most extensively used nanoparticles (NPs) TiO2 NPs (n-TiO2) and ZnO NPs (n-ZnO) versus their individual cytotoxicities on a model ammonia-oxidizing bacterium, Nitrosomonas europaea, were investigated at both physiological and transcriptional levels. n-ZnO exerted more serious impairment effects on cell morphology, cell density, membrane integrity, and ammonia monooxygenase activity than n-TiO2. However, the co-existing n-TiO2 displayed a dose-dependent mitigation effect on n-ZnO cytotoxicity. Consistently, the n-TiO2 and n-ZnO mixture-impacted global transcriptional expression profile, obtained with the whole-genome microarray technique, was more comparable to the n-TiO2-impacted one than that impacted by n-ZnO. The expressions of numerous genes associated with heavy metal scavenging, DNA repair, and oxidative stress response were less up-regulated under the binary impacts of NP mixture than n-ZnO. Moreover, only n-ZnO alone stimulated the up-regulations of heavy metal resistance genes, which further implied the capacity of co-existing n-TiO2 to alleviate n-ZnO cytotoxicity. In addition, the damage of cell membrane structures and the suppression of cell membrane biogenesis-related gene expressions under the influence of either individual NPs or their combinations strongly suggested that the interruption of cell membranes and the associated metabolic activities would probably be one of NPs' critical cytotoxicity mechanisms.

  17. The partial characterization of purified nitrite reductase and hydroxylamine oxidase from Nitrosomonas europaea

    PubMed Central

    Ritchie, G. A. F.; Nicholas, D. J. D.

    1974-01-01

    Nitrite reductase has been separated from cell-free extracts of Nitrosomonas and partially purified from hydroxylamine oxidase by polyacrylamide-gel electrophoresis. In its oxidized state the enzyme, which did not contain haem, had an extinction maximum at 590nm, which was abolished on reduction. Sodium diethyldithiocarbamate was a potent inhibitor of nitrite reductase. Enzyme activity was stimulated 2.5-fold when remixed with hydroxylamine oxidase, but was unaffected by mammalian cytochrome c. The enzyme also exhibited a low hydroxylamine-dependent nitrite reductase activity. The results suggest that this enzyme is similar to the copper-containing `denitrifying enzyme' of Pseudomonas denitrificans. A dithionite-reduced, 465nm-absorbing haemoprotein was associated with homogeneous preparations of hydroxylamine oxidase. The band at 465nm maximum was not reduced during the oxidation of hydroxylamine although the extinction was abolished on addition of hydroxylamine, NO2− or CO. These last-named compounds when added to the oxidized enzyme precluded the appearance of the 465nm-absorption band on addition of dithionite. Several properties of 465nm-absorbing haemoprotein are described. PMID:4154745

  18. Determination of the Effects of Medium Composition on the Monochloramine Disinfection Kinetics of Nitrosomonas europaea by the Propidium Monoazide Quantitative PCR and Live/Dead BacLight Methods

    EPA Science Inventory

    Various media compositions (phosphate 1-50 mM; ionic strength 2.8-150 meq/L) significantly affected Nitrosomonas europaea monochloramine disinfection kinetics determined by Live/Dead BacLight (LD) and propidium monoazide quantitative PCR (PMA-qPCR) methods (lag coefficient 37-490...

  19. The divergent AmoC3 subunit of ammonia monooxygenase functions as part of a stress response system in Nitrosomonas europaea.

    PubMed

    Berube, Paul M; Stahl, David A

    2012-07-01

    The ammonia monooxygenase of chemolithotrophic ammonia-oxidizing bacteria (AOB) catalyzes the first step in ammonia oxidation by converting ammonia to hydroxylamine. The monooxygenase of Nitrosomonas europaea is encoded by two nearly identical operon copies (amoCAB(1,2)). Several AOB, including N. europaea, also possess a divergent monocistronic copy of amoC (amoC(3)) of unknown function. Previous work suggested a possible functional role for amoC(3) as part of the σ(E) stress response regulon during the recovery of N. europaea from extended ammonia starvation, thus indicating its importance during the exit of cells from starvation. We here used global transcription analysis to show that expression of amoC(3) is part of a general poststarvation cellular response system in N. europaea. We also found that amoC(3) is required for an efficient response to some stress conditions, as deleting this gene impaired growth at elevated temperatures and recovery following starvation under high oxygen tensions. Deletion of the σ(32) global stress response regulator demonstrated that the heat shock regulon plays a significant role in mediating the recovery of N. europaea from starvation. These findings provide the first described phenotype associated with the divergent AmoC(3) subunit which appears to function as a stress-responsive subunit capable of maintaining ammonia oxidation activity under stress conditions. While this study was limited to starvation and heat shock, it is possible that the AmoC(3) subunit may be responsive to other membrane stressors (e.g., solvent or osmotic shocks) that are prevalent in the environments of AOB.

  20. The Divergent AmoC3 Subunit of Ammonia Monooxygenase Functions as Part of a Stress Response System in Nitrosomonas europaea

    PubMed Central

    Berube, Paul M.

    2012-01-01

    The ammonia monooxygenase of chemolithotrophic ammonia-oxidizing bacteria (AOB) catalyzes the first step in ammonia oxidation by converting ammonia to hydroxylamine. The monooxygenase of Nitrosomonas europaea is encoded by two nearly identical operon copies (amoCAB1,2). Several AOB, including N. europaea, also possess a divergent monocistronic copy of amoC (amoC3) of unknown function. Previous work suggested a possible functional role for amoC3 as part of the σE stress response regulon during the recovery of N. europaea from extended ammonia starvation, thus indicating its importance during the exit of cells from starvation. We here used global transcription analysis to show that expression of amoC3 is part of a general poststarvation cellular response system in N. europaea. We also found that amoC3 is required for an efficient response to some stress conditions, as deleting this gene impaired growth at elevated temperatures and recovery following starvation under high oxygen tensions. Deletion of the σ32 global stress response regulator demonstrated that the heat shock regulon plays a significant role in mediating the recovery of N. europaea from starvation. These findings provide the first described phenotype associated with the divergent AmoC3 subunit which appears to function as a stress-responsive subunit capable of maintaining ammonia oxidation activity under stress conditions. While this study was limited to starvation and heat shock, it is possible that the AmoC3 subunit may be responsive to other membrane stressors (e.g., solvent or osmotic shocks) that are prevalent in the environments of AOB. PMID:22544266

  1. Insights into glycogen metabolism in chemolithoautotrophic bacteria from distinctive kinetic and regulatory properties of ADP-glucose pyrophosphorylase from Nitrosomonas europaea.

    PubMed

    Machtey, Matías; Kuhn, Misty L; Flasch, Diane A; Aleanzi, Mabel; Ballicora, Miguel A; Iglesias, Alberto A

    2012-11-01

    Nitrosomonas europaea is a chemolithoautotroph that obtains energy by oxidizing ammonia in the presence of oxygen and fixes CO(2) via the Benson-Calvin cycle. Despite its environmental and evolutionary importance, very little is known about the regulation and metabolism of glycogen, a source of carbon and energy storage. Here, we cloned and heterologously expressed the genes coding for two major putative enzymes of the glycogen synthetic pathway in N. europaea, ADP-glucose pyrophosphorylase and glycogen synthase. In other bacteria, ADP-glucose pyrophosphorylase catalyzes the regulatory step of the synthetic pathway and glycogen synthase elongates the polymer. In starch synthesis in plants, homologous enzymes play similar roles. We purified to homogeneity the recombinant ADP-glucose pyrophosphorylase from N. europaea and characterized its kinetic, regulatory, and oligomeric properties. The enzyme was allosterically activated by pyruvate, oxaloacetate, and phosphoenolpyruvate and inhibited by AMP. It had a broad thermal and pH stability and used different divalent metal ions as cofactors. Depending on the cofactor, the enzyme was able to accept different nucleotides and sugar phosphates as alternative substrates. However, characterization of the recombinant glycogen synthase showed that only ADP-Glc elongates the polysaccharide, indicating that ATP and glucose-1-phosphate are the physiological substrates of the ADP-glucose pyrophosphorylase. The distinctive properties with respect to selectivity for substrates and activators of the ADP-glucose pyrophosphorylase were in good agreement with the metabolic routes operating in N. europaea, indicating an evolutionary adaptation. These unique properties place the enzyme in a category of its own within the family, highlighting the unique regulation in these organisms.

  2. Expression of merA, amoA and hao in continuously cultured Nitrosomonas europaea cells exposed to zinc chloride additions.

    PubMed

    Radniecki, Tyler S; Semprini, Lewis; Dolan, Mark E

    2009-02-01

    The effects of ZnCl2 additions on a mercuric reductase, merA, ammonia monooxygenase, amoA, and hydroxylamine (NH2OH) oxidoreductase, hao, gene expression were examined in continuously cultured Nitrosomonas europaea cells. The reactor was operated for 85 days with a 6.9 d hydraulic retention time and with four successive additions of ZnCl2 achieving maximum concentrations from 3 to 90 microM Zn2+. Continuously cultured N. europaea cells were more resistant to Zn2+ inhibition than previously examined batch cultured cells due to the presence of Mg2+ in the growth media, suggesting that Zn2+ enters the cell through Mg2+ import channels. The maximum merA up-regulation was 45-fold and expression increased with increases in Zn2+ concentration and decreased as Zn2+ concentrations decreased. Although Zn2+ irreversibly inactivated ammonia oxidation in N. europaea, the addition of either 600 microM CuSO4 or 2250 microM MgSO4 protected N. europaea from ZnCl2 inhibition, indicating a competition between Zn2+ and Cu2+/Mg2+ for uptake and/or AMO active sites. Since ZnCl2 inhibition is irreversible and amoA was up-regulated at 30 and 90 microM additions, it is hypothesized that de novo synthesis of the AMO enzyme is needed to overcome inhibition. The up-regulation of merA during exposure to non-inhibitory Zn2+ levels indicates that merA is an excellent early warning signal for Zn2+ inhibition.

  3. Insights into Glycogen Metabolism in Chemolithoautotrophic Bacteria from Distinctive Kinetic and Regulatory Properties of ADP-Glucose Pyrophosphorylase from Nitrosomonas europaea

    PubMed Central

    Machtey, Matías; Kuhn, Misty L.; Flasch, Diane A.; Aleanzi, Mabel; Ballicora, Miguel A.

    2012-01-01

    Nitrosomonas europaea is a chemolithoautotroph that obtains energy by oxidizing ammonia in the presence of oxygen and fixes CO2 via the Benson-Calvin cycle. Despite its environmental and evolutionary importance, very little is known about the regulation and metabolism of glycogen, a source of carbon and energy storage. Here, we cloned and heterologously expressed the genes coding for two major putative enzymes of the glycogen synthetic pathway in N. europaea, ADP-glucose pyrophosphorylase and glycogen synthase. In other bacteria, ADP-glucose pyrophosphorylase catalyzes the regulatory step of the synthetic pathway and glycogen synthase elongates the polymer. In starch synthesis in plants, homologous enzymes play similar roles. We purified to homogeneity the recombinant ADP-glucose pyrophosphorylase from N. europaea and characterized its kinetic, regulatory, and oligomeric properties. The enzyme was allosterically activated by pyruvate, oxaloacetate, and phosphoenolpyruvate and inhibited by AMP. It had a broad thermal and pH stability and used different divalent metal ions as cofactors. Depending on the cofactor, the enzyme was able to accept different nucleotides and sugar phosphates as alternative substrates. However, characterization of the recombinant glycogen synthase showed that only ADP-Glc elongates the polysaccharide, indicating that ATP and glucose-1-phosphate are the physiological substrates of the ADP-glucose pyrophosphorylase. The distinctive properties with respect to selectivity for substrates and activators of the ADP-glucose pyrophosphorylase were in good agreement with the metabolic routes operating in N. europaea, indicating an evolutionary adaptation. These unique properties place the enzyme in a category of its own within the family, highlighting the unique regulation in these organisms. PMID:22961847

  4. Regulation of membrane fixation and energy production/conversion for adaptation and recovery of ZnO nanoparticle impacted Nitrosomonas europaea.

    PubMed

    Wu, Junkang; Lu, Huijie; Zhu, Guangcan; Chen, Lianghui; Chang, Yan; Yu, Ran

    2017-04-01

    The ZnO nanoparticle (NP) effects on typical ammonia-oxidizing bacteria, Nitrosomonas europaea in a chemostat bioreactor, and the cells' toxicity adaptation and recovery potentials were explored. Hardly any inhibition was observed when the NP concentration was high up to 10 mg/L. The cells exposed to 50 mg/L ZnO NPs displayed time-dependent impairment and recovery potentials in terms of cell density, membrane integrity, nitrite production rate, and ammonia monooxygenase activity. The 6-h NP stress impaired cells were nearly completely restored during a 12-h recovery incubation, while the longer exposure time would cause irretrievable cell damage. Microarray analysis further indicated the transcriptional adaptation of N. europaea to NP stress. The regulations of genes encoding for membrane permeability or osmoprotectant, membrane integrity preservation, and inorganic ion transport during NP exposure and cell recovery revealed the importance of membrane fixation and the associated metabolisms for cells' self-protection and the following recovery from NP stress. The oxidative phosphorylation, carbon assimilation, and tricarboxylic acid (TCA) cycling pathways involved in the cells' antitoxicity activities and would promote the energy production/conversion efficiency for cell recovery. The heavy metal resistance, histidine metabolism, toxin-antitoxin defense, glycolysis, and sulfate reduction pathways were also suggested to participate in the cell detoxication and recovery processes. All these findings provided valuable insights into the mechanisms of cell-mediated ZnO NP cytotoxicity and their potential impacts on wastewater nitrogen removal system.

  5. Short-term effects of TiO2, CeO2, and ZnO nanoparticles on metabolic activities and gene expression of Nitrosomonas europaea.

    PubMed

    Yu, Ran; Fang, Xiaohua; Somasundaran, Ponisseril; Chandran, Kartik

    2015-06-01

    Nanosized TiO2 (n-TiO2), CeO2 (n-CeO2), and ZnO (n-ZnO) and bulk ZnO were chosen for a 4-h exposure study on a model ammonia oxidizing bacterium, Nitrosomonas europaea. n-ZnO displayed the most serious cytotoxicity while n-TiO2 was the least toxic one. The change of cell morphologies, the retardance of specific oxygen uptake rates and ammonia oxidation rates, and the depression of amoA gene expressions under NP stresses were generally observed when the cell densities and membrane integrities were not significantly impaired yet. The TEM imaging and the synchrotron X-ray fluorescence microscopy of the NPs impacted cells revealed the increase of the corresponding intracellular Ti, Ce or Zn contents and suggested the intracellular NP accumulation. The elevation of intracellular S contents accompanied with higher K contents implied the possible activation of thiol-containing glutathione and thioredoxin production for NP stress alleviation. The NP cytotoxicity was not always a function of NP concentration. The 200 mg L(-1) n-TiO2 or n-CeO2 impacted cells displayed the similar ammonia oxidation activities but higher amoA gene expression levels than the 20 mg L(-1) NPs impacted ones. Such phenomenon further indicated the possible establishment of an anti-toxicity mechanism in N. europaea at the genetic level to redeem the weakened AMO activities along with the NP aggregation effects.

  6. Effect of Low-Density Static Magnetic Field on the Oxidation of Ammonium by Nitrosomonas europaea and by Activated Sludge in Municipal Wastewater.

    PubMed

    Filipič, Jasmina; Kraigher, Barbara; Tepuš, Brigita; Kokol, Vanja; Mandić-Mulec, Ines

    2015-06-01

    Ammonium removal is a key step in biological wastewater treatment and novel approaches that improve this process are in great demand. The aim of this study is to test the hypothesis that ammonium removal from wastewater can be stimulated by static magnetic fields. This was achieved by analysis of the effects of static magnetic field (SMF) on the growth and activity of Nitrosomonas europaea, a key ammonia-oxidising bacterium, where increased growth and increased ammonia oxidation rate were detected when bacteria were exposed to SMF at 17 mT. Additionally, the effect of SMF on mixed cultures of ammonia oxidisers in activated sludge, incubated in sequencing batch bioreactors simulating wastewater treatment process, was assessed. SMFs of 30 and 50 mT, but not of 10 mT, increased ammonium oxidation rate in municipal wastewater by up to 77% and stimulated ammonia oxidiser growth. The results demonstrate the potential for use of static magnetic fields in increasing ammonium removal rates in biological wastewater treatment plants.

  7. Stresses exerted by ZnO, CeO2 and anatase TiO2 nanoparticles on the Nitrosomonas europaea.

    PubMed

    Fang, Xiaohua; Yu, Ran; Li, Bingquan; Somasundaran, Ponisseril; Chandran, Kartik

    2010-08-15

    Recent studies have shown that nano-bio interfaces are the most complex and the least understood. Notably, nanotoxicity of these nanoparticles is not even well recognized. In this work, we examined the toxic effects of different nanoparticles on bacteria cells (Nitrosomonas europaea). The four nanoparticles involved are: 25 nm anatase TiO(2), 200 nm anatase TiO(2), ZnO and CeO(2) particles. These particles will have different electrical charges in the cell cultivating media. It has been observed that even with only 4 h of dosing, all of the particles caused apparent morphological damage to the cells. Experimental results suggest that ZnO particles exert the stress on cells by its dissolution and releasing of Zn(2+) ions. The TEM and AUC (analytical ultracentrifuge) result suggest that cells become heavier in presence of CeO(2) and TiO(2) particles. No visible clear intrusions of bulk nanoparticles were observed. However, both the analytical ultracentrifuge and TEM results show that cells are heavier when being damaged.

  8. Characterization of metabolites formed during the biotransformation of 17alpha-ethinylestradiol by Nitrosomonas europaea in batch and continuous flow bioreactors.

    PubMed

    Skotnicka-Pitak, J; Khunjar, W O; Love, N G; Aga, D S

    2009-05-15

    The biotransformation of 17alpha-ethinylestradiol (EE2) by an ammonia oxidizing bacteria, Nitrosomonas europaea, grown in batch (ammonia-rich) and continuous flow (chemostat, ammonia-limited) reactors was investigated. Both C-14 labeled EE2 (10 gammag/L) and unlabeled EE2 (1 mg/L) were used to facilitate metabolite identification under environmentally relevant physiological conditions. Whole cell ammonia monooxygenase (AMO) activity was not inhibited at the EE2 concentrations used in this study. Characterization of the primary metabolite formed during batch cultivation by liquid chromatography/ion-trap mass spectrometry (LC-ITMS) and nuclear magnetic resonance (NMR) spectroscopy showed modification at the ethinyl group and addition of a carboxyl group. This metabolite (M386) (revealed by m/z 385 in negative mode electrospray LC/ MS) was not formed in the abiotic control. In contrast, biotransformation of EE2 under continuous flow conditions showed formation of a monohydroxylated EE2 (revealed by m/z 311), but not M386. Furthermore, nitrated EE2 derivatives were formed in both batch and continuous flow cultures, as a result of abiotic transformation of EE2 in the presence of high concentrations of nitrite in the bioreactors. Results from this study underscore the importance of physiological state and growth conditions as critical variables that can dictate the metabolic pathway for EE2 biodegradation and the nature of byproducts formed.

  9. Identification of function and mechanistic insights of guanine deaminase from Nitrosomonas europaea: role of the C-terminal loop in catalysis.

    PubMed

    Bitra, Aruna; Hussain, Bhukya; Tanwar, Ajay Singh; Anand, Ruchi

    2013-05-21

    NE0047 from Nitrosomonas europaea has been annotated as a zinc-dependent deaminase; however, the substrate specificity is unknown because of the low level of structural similarity and sequence identity compared to other family members. In this study, the function of NE0047 was established as a guanine deaminase (catalytic efficiency of 1.2 × 10(5) M(-1) s(-1)), exhibiting secondary activity towards ammeline. The structure of NE0047 in the presence of the substrate analogue 8-azaguanine was also determined to a resolution of 1.9 Å. NE0047 crystallized as a homodimer in an asymmetric unit. It was found that the extreme nine-amino acid C-terminal loop forms an active site flap; in one monomer, the flap is in the closed conformation and in the other in the open conformation with this loop region exposed to the solvent. Calorimetric data obtained using the full-length version of the enzyme fit to a sequential binding model, thus supporting a cooperative mode of ligand occupancy. In contrast, the mutant form of the enzyme (ΔC) with the deletion of the extreme nine amino acids follows an independent model of ligand occupancy. In addition, the ΔC mutant also does not exhibit any enzyme activity. Therefore, we propose that the progress of the reaction is communicated via changes in the conformation of the C-terminal flap and the closed form of the enzyme is the catalytically active form, while the open form allows for product release. The catalytic mechanism of deamination was also investigated, and we found that the mutagenesis of the highly conserved active site residues Glu79 and Glu143 resulted in a complete loss of activity and concluded that they facilitate the reaction by serving as proton shuttles.

  10. An electrophoretic study of the thermal- and reductant-dependent aggregation of the 27 kDa component of ammonia monooxygenase from Nitrosomonas europaea.

    PubMed

    Hyman, M R; Arp, D J

    1993-07-01

    Standard protocols for sample preparation for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) typically involve the combined use of heat and a reductant to fully disrupt protein-protein interactions and allow for constant ratios of SDS-binding to individual polypeptides. However, 14C-labeled forms of the membrane-bound, active-site-containing 27 kDa polypeptide of ammonia monooxygenase from Nitrosomonas europaea undergo an aggregation reaction when cells or membranes are heated in the presence of SDS-PAGE sample buffer. The aggregate produced after heating at 100 degrees C is a soluble complex which fails to enter the stacking gel in discontinuous SDS-PAGE gels. The extent of the aggregation reaction is dependent on the temperature of sample preparation, and the reaction exhibits first-order kinetics at 65 degrees C and 100 degrees C (rates constants = 0.07 and 0.35 min-1, respectively). The rate of the aggregation reaction is further dependent on the concentration of reductant used in the sample buffer. However, the concentration of SDS does not significantly affect the rate of aggregation. The aggregated form of the 27 kDA polypeptide can be isolated by gel-permeation chromatography in the presence of SDS. The aggregated protein can also be returned to the monomeric state by incubation at high pH in the presence of SDS. The aggregation reaction also occurs with 14C2H2-labeled polypeptides in other species of autotrophic nitrifiers and a methanotrophic bacterium which expresses the particulate form of methane monooxygenase. We conclude that strongly hydrophobic amino acid sequences present in ammonia monooxygenase are responsible for the aggregation phenomenon.

  11. Kinetic Studies of Ammonia Monooxygenase Inhibition in Nitrosomonas europaea by Hydrocarbons and Halogenated Hydrocarbons in an Optimized Whole-Cell Assay

    PubMed Central

    Keener, William K.; Arp, Daniel J.

    1993-01-01

    The inhibitory effects of 15 hydrocarbons and halogenated hydrocarbons on NH3 oxidation by ammonia monooxygenase (AMO) in intact cells of the nitrifying bacterium Nitrosomonas europaea were determined. Determination of AMO activity, measured as NO2- production, required coupling of hydroxylamine oxidoreductase (HAO) activity with NH3-dependent NH2OH production by AMO. Hydrazine, an alternate substrate for HAO, was added to the reaction mixtures as a source of reductant for AMO. Most inhibitors exhibited competitive or noncompetitive inhibition patterns. The competitive character generally decreased (KiE/KiES increased) as the molecular size of the inhibitors increased. For example, CH4 and C2H4 were competitive inhibitors of NH3 oxidation, whereas the remaining alkanes (up to C4) and monohalogenated (Cl, Br, I) alkanes were noncompetitive. Oxidation of C2H5Br (noncompetitive) increased as the NH4+ concentration increased up to 40 mM, whereas oxidations of inhibitors with competitive character (KiE ≪ KiES) were diminished at 40 mM NH4+. Multichlorinated compounds produced nonlinear Lineweaver-Burk plots. Iodinated alkanes (CH3I, C2H5I) and C2Cl4 were potent inhibitors of NH3 oxidation. Maximum rates of NH3, C2H4, and C2H6 oxidations were approximately equivalent, suggesting a common rate-determining step. These data support an active-site model for AMO consisting of an NH3-binding site and a second site that binds noncompetitive inhibitors, with oxidation occurring at either site. PMID:16349014

  12. OXIDATION OF METHYL FLUORIDE AND DIMETHYL ETHER BY AMMONIA MONOOXYGENASE IN NITROSOMONAS EUROPAEA. (R825689C009)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  13. Determination of the effects of medium composition on the monochloramine disinfection kinetics of Nitrosomonas europaea by the propidium monoazide quantitative PCR and Live/Dead BacLight methods.

    PubMed

    Wahman, David G; Schrantz, Karen A; Pressman, Jonathan G

    2010-12-01

    Various medium compositions (phosphate, 1 to 50 mM; ionic strength, 2.8 to 150 meq/liter) significantly affected Nitrosomonas europaea monochloramine disinfection kinetics, as determined by the Live/Dead BacLight (LD) and propidium monoazide quantitative PCR (PMA-qPCR) methods (lag coefficient, 37 to 490 [LD] and 91 to 490 [PMA-qPCR] mg·min/liter; Chick-Watson rate constant, 4.0 × 10(-3) to 9.3 × 10(-3) [LD] and 1.6 × 10(-3) to 9.6 × 10(-3) [PMA-qPCR] liter/mg·min). Two competing effects may account for the variation in disinfection kinetic parameters: (i) increasing kinetics (disinfection rate constant [k] increased, lag coefficient [b] decreased) with increasing phosphate concentration and (ii) decreasing kinetics (k decreased, b increased) with increasing ionic strength. The results support development of a standard medium for evaluating disinfection kinetics in drinking water.

  14. Expression of merA, trxA, amoA, and hao in continuously cultured Nitrosomonas europaea cells exposed to cadmium sulfate additions.

    PubMed

    Radniecki, Tyler S; Semprini, Lewis; Dolan, Mark E

    2009-12-01

    The effects of CdSO(4) additions on the gene expressions of a mercury reductase, merA, an oxidative stress protein, trxA, the ammonia-monooxygenase enzyme (AMO), amoA, and the hydroxylamine oxidoreductase enzyme (HAO), hao, were examined in continuously cultured N. europaea cells. The reactor was fed 50 mM NH(4)+ and was operated for 78 days with a 6.9 days hydraulic retention time. Over this period, six successive batch additions of CdSO(4) were made with increasing maximum concentrations ranging from 1 to 60 microM Cd(2+). The expression of merA was highly correlated with the level of Cd(2+) within the reactor (Rs = 0.90) with significant up-regulation measured at non-inhibitory Cd(2+) concentrations. Cd(2+) appears to target AMO specifically at lower concentrations and caused oxidative stress at higher concentrations, as indicated by the SOURs (specific oxygen uptake rates) and the up-regulation of trxA. Since Cd(2+) inhibition is irreversible and amoA was up-regulated in response to Cd(2+) inhibition, it is hypothesized that de novo synthesis of the AMO enzyme occurred and was responsible for the observed recovery in activity. Continuously cultured N. europaea cells were more resistant to Cd(2+) inhibition than previously examined batch cultured cells due to the presence of Mg(2+) and Ca(2+) in the growth media, suggesting that Cd(2+) enters the cell through Mg(2+) and Ca(2+) import channels. The up-regulation of merA during exposure to non-inhibitory Cd(2+) levels indicates that merA is an excellent early warning signal for Cd(2+) inhibition.

  15. Modulation of the ligand-field anisotropy in a series of ferric low-spin cytochrome c mutants derived from Pseudomonas aeruginosa cytochrome c-551 and Nitrosomonas europaea cytochrome c-552: a nuclear magnetic resonance and electron paramagnetic resonance study.

    PubMed

    Zoppellaro, Giorgio; Harbitz, Espen; Kaur, Ravinder; Ensign, Amy A; Bren, Kara L; Andersson, K Kristoffer

    2008-11-19

    Cytochromes of the c type with histidine-methionine (His-Met) heme axial ligation play important roles in electron-transfer reactions and in enzymes. In this work, two series of cytochrome c mutants derived from Pseudomonas aeruginosa (Pa c-551) and from the ammonia-oxidizing bacterium Nitrosomonas europaea (Ne c-552) were engineered and overexpressed. In these proteins, point mutations were induced in a key residue (Asn64) near the Met axial ligand; these mutations have a considerable impact both on heme ligand-field strength and on the Met orientation and dynamics (fluxionality), as judged by low-temperature electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectra. Ne c-552 has a ferric low-spin (S = 1/2) EPR signal characterized by large g anisotropy with g(max) resonance at 3.34; a similar large g(max) value EPR signal is found in the mitochondrial complex III cytochrome c1. In Ne c-552, deletion of Asn64 (NeN64Delta) changes the heme ligand field from more axial to rhombic (small g anisotropy and g(max) at 3.13) and furthermore hinders the Met fluxionality present in the wild-type protein. In Pa c-551 (g(max) at 3.20), replacement of Asn64 with valine (PaN64V) induces a decrease in the axial strain (g(max) at 3.05) and changes the Met configuration. Another set of mutants prepared by insertion (ins) and/or deletion (Delta) of a valine residue adjacent to Asn64, resulting in modifications in the length of the axial Met-donating loop (NeV65Delta, NeG50N/V65Delta, PaN50G/V65ins), did not result in appreciable alterations of the originally weak (Ne c-552) or very weak (Pa c-551) axial field but had an impact on Met orientation, fluxionality, and relaxation dynamics. Comparison of the electronic fingerprints in the overexpressed proteins and their mutants reveals a linear relationship between axial strain and average paramagnetic heme methyl shifts, irrespective of Met orientation or dynamics. Thus, for these His-Met axially coordinated Fe

  16. Genome sequence of Nitrosomonas sp. strain AL212, an ammonia-oxidizing bacterium sensitive to high levels of ammonia.

    PubMed

    Suwa, Yuichi; Yuichi, Suwa; Norton, Jeanette M; Bollmann, Annette; Klotz, Martin G; Stein, Lisa Y; Laanbroek, Hendrikus J; Arp, Daniel J; Goodwin, Lynne A; Chertkov, Olga; Held, Brittany; Bruce, David; Detter, J Chris; Detter, Janine C; Tapia, Roxanne; Han, Cliff S

    2011-09-01

    Nitrosomonas sp. strain AL212 is an obligate chemolithotrophic ammonia-oxidizing bacterium (AOB) that was originally isolated in 1997 by Yuichi Suwa and colleagues. This organism belongs to Nitrosomonas cluster 6A, which is characterized by sensitivity to high ammonia concentrations, higher substrate affinity (lower K(m)), and lower maximum growth rates than strains in Nitrosomonas cluster 7, which includes Nitrosomonas europaea and Nitrosomonas eutropha. Genome-informed studies of this ammonia-sensitive cohort of AOB are needed, as these bacteria are found in freshwater environments, drinking water supplies, wastewater treatment systems, and soils worldwide.

  17. Nitrosomonas communis strain YNSRA, an ammonia-oxidizing bacterium, isolated from the reed rhizoplane in an aquaponics plant.

    PubMed

    Tokuyama, Tatsuaki; Mine, Atsusi; Kamiyama, Kaoru; Yabe, Ryuichi; Satoh, Kazuo; Matsumoto, Hirotoshi; Takahashi, Reiji; Itonaga, Koji

    2004-01-01

    An ammonia-oxidizing bacterium (strain YNSRA) was isolated from the rhizoplane of the reed (Phragmites communis) used in an aquaponics plant which is a wastewater treatment plant. Strain YNSRA was identified as Nitrosomonas communis by taxonomic studies. The hydroxylamine-cytochrome c reductase (HCR) of strain YNSRA was found to have a higher activity (25.60 u/mg) than that of Nitrosomonas europaea ATCC25978T (8.94 u/mg). Ribulose-1,5-bisphosphate carboxylase (RubisCO) activity was detected at very low levels in strain YNSRA, whereas strain ATCC25978T had definite activity.

  18. US EPA Research on Monochloramine Disinfection Kinetics of Nitrosomonas europaea

    EPA Science Inventory

    Based on utility surveys, 30 to 63% of utilities practicing chloramination for secondary disinfection experience nitrification episodes (American Water Works Association 2006). Nitrification in drinking water distribution systems is undesirable and may result in water quality deg...

  19. USEPA Research on Monochloramine Disinfection Kinetics of Nitrosomonas Europaea

    EPA Science Inventory

    Based on utility surveys, 30 to 63% of utilities practicing chloramination for secondary disinfection experience nitrification episodes (American Water Works Association 2006). Nitrification in drinking water distribution systems is undesirable and may result in water quality deg...

  20. Monochloramine Cometabolism by Nitrosomonas europaea under Drinking Water Conditions

    EPA Science Inventory

    Chloramine use is widespread in United States drinking water systems as a secondary disinfectant. While beneficial from the perspective of controlling disinfectant by-product formation, chloramination may promote the growth of nitrifying bacteria because ammonia is present. At ...

  1. Complete Genome Sequence of the Ammonia-Oxidizing Bacterium and Obligate Chemolithoautotroph Nitrosomonas europaea†

    PubMed Central

    Chain, Patrick; Lamerdin, Jane; Larimer, Frank; Regala, Warren; Lao, Victoria; Land, Miriam; Hauser, Loren; Hooper, Alan; Klotz, Martin; Norton, Jeanette; Sayavedra-Soto, Luis; Arciero, Dave; Hommes, Norman; Whittaker, Mark; Arp, Daniel

    2003-01-01

    Nitrosomonas europaea (ATCC 19718) is a gram-negative obligate chemolithoautotroph that can derive all its energy and reductant for growth from the oxidation of ammonia to nitrite. Nitrosomonas europaea participates in the biogeochemical N cycle in the process of nitrification. Its genome consists of a single circular chromosome of 2,812,094 bp. The GC skew analysis indicates that the genome is divided into two unequal replichores. Genes are distributed evenly around the genome, with ∼47% transcribed from one strand and ∼53% transcribed from the complementary strand. A total of 2,460 protein-encoding genes emerged from the modeling effort, averaging 1,011 bp in length, with intergenic regions averaging 117 bp. Genes necessary for the catabolism of ammonia, energy and reductant generation, biosynthesis, and CO2 and NH3 assimilation were identified. In contrast, genes for catabolism of organic compounds are limited. Genes encoding transporters for inorganic ions were plentiful, whereas genes encoding transporters for organic molecules were scant. Complex repetitive elements constitute ca. 5% of the genome. Among these are 85 predicted insertion sequence elements in eight different families. The strategy of N. europaea to accumulate Fe from the environment involves several classes of Fe receptors with more than 20 genes devoted to these receptors. However, genes for the synthesis of only one siderophore, citrate, were identified in the genome. This genome has provided new insights into the growth and metabolism of ammonia-oxidizing bacteria. PMID:12700255

  2. Complete Genome Sequence of Nitrosomonas ureae Strain Nm10, an Oligotrophic Group 6a Nitrosomonad

    PubMed Central

    Kozlowski, Jessica A.; Kits, K. Dimitri

    2016-01-01

    The complete genome of Nitrosomonas ureae strain Nm10, a mesophilic betaproteobacterial ammonia oxidizer isolated from Mediterranean soils in Sardinia, Italy, is reported here. This genome represents a cluster 6a nitrosomonad. PMID:26966201

  3. Genome Sequence of Nitrosomonas communis Strain Nm2, a Mesophilic Ammonia-Oxidizing Bacterium Isolated from Mediterranean Soil

    PubMed Central

    Kozlowski, Jessica A.; Kits, K. Dimitri

    2016-01-01

    The complete genome sequence of Nitrosomonas communis strain Nm2, a mesophilic betaproteobacterial ammonia oxidizer isolated from Mediterranean soils in Corfu, Greece, is reported here. This is the first genome to describe a cluster 8 Nitrosomonas species and represents an ammonia-oxidizing bacterium commonly found in terrestrial ecosystems. PMID:26769932

  4. Whole-genome analysis of the ammonia-oxidizing bacterium, Nitrosomonas eutropha C91: implications for niche adaptation

    SciTech Connect

    Stein, Lisa Y; Arp, D J; Berube, PM; Chain, Patrick S. G.; Hauser, Loren John; Jetten, MSM; Klotz, Martin G; Larimer, Frank W; Norton, Jeanette M.; Op den Camp, HJM; Shin, M; Wei, Xueming

    2007-12-01

    Analysis of the structure and inventory of the genome of Nitrosomonas eutropha C91 revealed distinctive features that may explain the adaptation of N. eutropha-like bacteria to N-saturated ecosystems. Multiple gene-shuffling events are apparent, including mobilized and replicated transposition, as well as plasmid or phage integration events into the 2.66 Mbp chromosome and two plasmids (65 and 56 kbp) of N. eutropha C91. A 117 kbp genomic island encodes multiple genes for heavy metal resistance, including clusters for copper and mercury transport, which are absent from the genomes of other ammonia-oxidizing bacteria (AOB). Whereas the sequences of the two ammonia monooxygenase and three hydroxylamine oxidoreductase gene clusters in N. eutropha C91 are highly similar to those of Nitrosomonas europaea ATCC 19718, a break of synteny in the regions flanking these clusters in each genome is evident. Nitrosomonas eutropha C91 encodes four gene clusters for distinct classes of haem-copper oxidases, two of which are not found in other aerobic AOB. This diversity of terminal oxidases may explain the adaptation of N. eutropha to environments with variable O2 concentrations and/or high concentrations of nitrogen oxides. As with N. europaea, the N. eutropha genome lacks genes for urease metabolism, likely disadvantaging nitrosomonads in low-nitrogen or acidic ecosystems. Taken together, this analysis revealed significant genomic variation between N. eutropha C91 and other AOB, even the closely related N. europaea, and several distinctive properties of the N. eutropha genome that are supportive of niche specialization.

  5. Whole-genome analysis of the ammonia-oxidizing bacterium, Nitrosomonas eutropha C91: implications for niche adaptation.

    PubMed

    Stein, Lisa Y; Arp, Daniel J; Berube, Paul M; Chain, Patrick S G; Hauser, Loren; Jetten, Mike S M; Klotz, Martin G; Larimer, Frank W; Norton, Jeanette M; Op den Camp, Huub J M; Shin, Maria; Wei, Xueming

    2007-12-01

    Analysis of the structure and inventory of the genome of Nitrosomonas eutropha C91 revealed distinctive features that may explain the adaptation of N. eutropha-like bacteria to N-saturated ecosystems. Multiple gene-shuffling events are apparent, including mobilized and replicated transposition, as well as plasmid or phage integration events into the 2.66 Mbp chromosome and two plasmids (65 and 56 kbp) of N. eutropha C91. A 117 kbp genomic island encodes multiple genes for heavy metal resistance, including clusters for copper and mercury transport, which are absent from the genomes of other ammonia-oxidizing bacteria (AOB). Whereas the sequences of the two ammonia monooxygenase and three hydroxylamine oxidoreductase gene clusters in N. eutropha C91 are highly similar to those of Nitrosomonas europaea ATCC 19718, a break of synteny in the regions flanking these clusters in each genome is evident. Nitrosomonas eutropha C91 encodes four gene clusters for distinct classes of haem-copper oxidases, two of which are not found in other aerobic AOB. This diversity of terminal oxidases may explain the adaptation of N. eutropha to environments with variable O(2) concentrations and/or high concentrations of nitrogen oxides. As with N. europaea, the N. eutropha genome lacks genes for urease metabolism, likely disadvantaging nitrosomonads in low-nitrogen or acidic ecosystems. Taken together, this analysis revealed significant genomic variation between N. eutropha C91 and other AOB, even the closely related N. europaea, and several distinctive properties of the N. eutropha genome that are supportive of niche specialization.

  6. Effects of Soil and Water Content on Methyl Bromide Oxidation by the Ammonia-Oxidizing Bacterium Nitrosomonas europaea†

    PubMed Central

    Duddleston, Khrystyne N.; Bottomley, Peter J.; Porter, Angela; Arp, Daniel J.

    2000-01-01

    Little information exists on the potential of NH3-oxidizing bacteria to cooxidize halogenated hydrocarbons in soil. A study was conducted to examine the cooxidation of methyl bromide (MeBr) by an NH3-oxidizing bacterium, Nitrosomonas europaea, under soil conditions. Soil and its water content modified the availability of NH4+ and MeBr and influenced the relative rates of substrate (NH3) and cosubstrate (MeBr) oxidations. These observations highlight the complexity associated with characterizing soil cooxidative activities when soil and water interact to differentially affect substrate and cosubstrate availabilities. PMID:10831449

  7. Fauna Europaea - Orthopteroid orders.

    PubMed

    Heller, Klaus-Gerhard; Bohn, Horst; Haas, Fabian; Willemse, Fer; de Jong, Yde

    2016-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant European terrestrial and freshwater animals, their geographical distribution at the level of countries and major islands (west of the Urals and excluding the Caucasus region), and some additional information. The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. The "Orthopteroid orders" is one of the 58 Fauna Europaea major taxonomic groups. It contains series of mostly well-known insect orders: Embiodea (webspinners), Dermaptera (earwigs), Phasmatodea (walking sticks), Orthoptera s.s. (grasshoppers, crickets, bush-crickets) and Dictyoptera with the suborders Mantodea (mantids), Blattaria (cockroaches) and Isoptera (termites). For the Orthopteroid orders, data from 35 families containing 1,371 species are included in this paper.

  8. Effect of free ammonia and free nitrous acid concentration on the anabolic and catabolic processes of an enriched Nitrosomonas culture.

    PubMed

    Vadivelu, Vel M; Keller, Jurg; Yuan, Zhiguo

    2006-12-05

    The effects of free ammonia (FA; NH(3)) and free nitrous acid (FNA; HNO(2)) concentrations on the metabolisms of an enriched ammonia oxidizing bacteria (AOB) culture were investigated using a method allowing the decoupling of growth and energy generation processes. A lab-scale sequencing batch reactor (SBR) was operated for the enrichment of an AOB culture. Fluorescent in-situ hybridization (FISH) analysis showed that 82% of the bacterial population in the SBR bound to the NEU probe specifically designed for Nitrosomonas europaea. Batch tests were carried out to measure the oxygen and ammonium consumption rates by the culture at various FA and FNA levels, in the presence or absence of inorganic carbon (CO(2), HCO(3) (-), and CO(3) (2-)). It was revealed that FA of up to 16.0 mgNH(3)-N . L(-1), which was the highest concentration used in this study, did not have any inhibitory effect on either the catabolic or anabolic processes of the Nitrosomonas culture. In contrast, FNA inhibited both the growth and energy production capabilities of the Nitrosomonas culture. The inhibition on growth initiated at approximately 0.10 mgHNO(2)-N . L(-1), and the data suggested that the biosynthesis was completely stopped at an FNA concentration of 0.40 mgHNO(2)-N . L(-1). The inhibition on energy generation initiated at a slightly lower level but the Nitrosomonas culture was still oxidizing ammonia at half of the maximum rate at an FNA concentration of 0.50-0.63 mgHNO(2)-N . L(-1). The affinity constant of the Nitrosomonas culture with respect to ammonia was determined to be 0.36 mgNH(3)-N . L(-1), independent of the presence or absence of inorganic carbon.

  9. Fauna Europaea: Gastrotricha

    PubMed Central

    d`Hondt, Jean-Loup; Kisielewski, Jacek; Todaro, M. Antonio; Tongiorgi, Paolo; Guidi, Loretta; Grilli, Paolo

    2015-01-01

    Abstract Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Gastrotricha are a meiobenthic phylum composed of 813 species known so far (2 orders, 17 families) of free-living microinvertebrates commonly present and actively moving on and into sediments of aquatic ecosystems, 339 of which live in fresh and brackish waters. The Fauna Europaea database includes 214 species of Chaetonotida (4 families) plus a single species of Macrodasyida incertae sedis. This paper deals with the 224 European freshwater species known so far, 9 of which, all of Chaetonotida, have been described subsequently and will be included in the next database version. Basic information on their biology and ecology are summarized, and a list of selected, main references is given. As a general conclusion the gastrotrich fauna from Europe is the best known compared with that of other continents, but shows some important gaps of knowledge in Eastern and Southern regions. PMID:26379467

  10. Fauna Europaea: Gastrotricha.

    PubMed

    Balsamo, Maria; D Hondt, Jean-Loup; Kisielewski, Jacek; Todaro, M Antonio; Tongiorgi, Paolo; Guidi, Loretta; Grilli, Paolo; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Gastrotricha are a meiobenthic phylum composed of 813 species known so far (2 orders, 17 families) of free-living microinvertebrates commonly present and actively moving on and into sediments of aquatic ecosystems, 339 of which live in fresh and brackish waters. The Fauna Europaea database includes 214 species of Chaetonotida (4 families) plus a single species of Macrodasyida incertae sedis. This paper deals with the 224 European freshwater species known so far, 9 of which, all of Chaetonotida, have been described subsequently and will be included in the next database version. Basic information on their biology and ecology are summarized, and a list of selected, main references is given. As a general conclusion the gastrotrich fauna from Europe is the best known compared with that of other continents, but shows some important gaps of knowledge in Eastern and Southern regions.

  11. Fauna europaea: Diptera - brachycera.

    PubMed

    Pape, Thomas; Beuk, Paul; Pont, Adrian Charles; Shatalkin, Anatole I; Ozerov, Andrey L; Woźnica, Andrzej J; Merz, Bernhard; Bystrowski, Cezary; Raper, Chris; Bergström, Christer; Kehlmaier, Christian; Clements, David K; Greathead, David; Kameneva, Elena Petrovna; Nartshuk, Emilia; Petersen, Frederik T; Weber, Gisela; Bächli, Gerhard; Geller-Grimm, Fritz; Van de Weyer, Guy; Tschorsnig, Hans-Peter; de Jong, Herman; van Zuijlen, Jan-Willem; Vaňhara, Jaromír; Roháček, Jindřich; Ziegler, Joachim; Majer, József; Hůrka, Karel; Holston, Kevin; Rognes, Knut; Greve-Jensen, Lita; Munari, Lorenzo; de Meyer, Marc; Pollet, Marc; Speight, Martin C D; Ebejer, Martin John; Martinez, Michel; Carles-Tolrá, Miguel; Földvári, Mihály; Chvála, Milan; Barták, Miroslav; Evenhuis, Neal L; Chandler, Peter J; Cerretti, Pierfilippo; Meier, Rudolf; Rozkosny, Rudolf; Prescher, Sabine; Gaimari, Stephen D; Zatwarnicki, Tadeusz; Zeegers, Theo; Dikow, Torsten; Korneyev, Valery A; Richter, Vera Andreevna; Michelsen, Verner; Tanasijtshuk, Vitali N; Mathis, Wayne N; Hubenov, Zdravko; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant multicellular European terrestrial and freshwater animals and their geographical distribution at the level of countries and major islands (east of the Urals and excluding the Caucasus region). The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing taxonomic specialists throughout Europe and is a unique (standard) reference suitable for many user communities in science, government, industry, nature conservation and education. The Diptera-Brachycera is one of the 58 Fauna Europaea major taxonomic groups, and data have been compiled by a network of 55 specialists. Within the two-winged insects (Diptera), the Brachycera constitute a monophyletic group, which is generally given rank of suborder. The Brachycera may be classified into the probably paraphyletic 'lower brachyceran grade' and the monophyletic Eremoneura. The latter contains the Empidoidea, the Apystomyioidea with a single Nearctic species, and the Cyclorrhapha, which in turn is divided into the paraphyletic 'aschizan grade' and the monophyletic Schizophora. The latter is traditionally divided into the paraphyletic 'acalyptrate grade' and the monophyletic Calyptratae. Our knowledge of the European fauna of Diptera-Brachycera varies tremendously among families, from the reasonably well known hoverflies (Syrphidae) to the extremely poorly known scuttle flies (Phoridae). There has been a steady growth in our knowledge of European Diptera for the last two centuries, with no apparent slow down, but there is a shift towards a larger fraction of the new species being found among the families of the nematoceran grade (lower Diptera), which due to a larger number of small

  12. Fauna Europaea: Mollusca - Bivalvia.

    PubMed

    Araujo, Rafael; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. For the Mollusca-Bivalvia, data from 5 families (Margaritiferidae, Unionidae, Sphaeriidae, Cyrenidae, Dreissenidae) containing 55 species are included in this paper. European freshwater bivalves belong to the Orders Unionoida and Cardiida. All the European unionoids are included in the superfamily Unionoidea, the freshwater mussels or naiads. The European cardiids belong to the following three superfamilies: Cardioidea, Cyrenoidea and Dreissenoidea. Among the Unionoidea there are the most imperilled animal groups on the planet while the Cardioidea includes the cosmopolitan genus Pisidium, the Cyrenoidea the Asiatic clam (Corbiculafluminea) and the Dreissenoidea the famous invasive zebra mussel (Dreissenapolymorpha). Basic information is summarized on their taxonomy and biology. Tabulations include a complete list of the current estimated families, genera and species.

  13. Traditional Uses, Phytochemistry, and Pharmacology of Olea europaea (Olive)

    PubMed Central

    Hashmi, Muhammad Ali; Khan, Afsar; Hanif, Muhammad; Farooq, Umar; Perveen, Shagufta

    2015-01-01

    Aim of the Review. To grasp the fragmented information available on the botany, traditional uses, phytochemistry, pharmacology, and toxicology of Olea europaea to explore its therapeutic potential and future research opportunities. Material and Methods. All the available information on O. europaea was collected via electronic search (using Pubmed, Scirus, Google Scholar, and Web of Science) and a library search. Results. Ethnomedical uses of O. europaea are recorded throughout the world where it has been used to treat various ailments. Phytochemical research had led to the isolation of flavonoids, secoiridoids, iridoids, flavanones, biophenols, triterpenes, benzoic acid derivatives, isochromans, and other classes of secondary metabolites from O. europaea. The plant materials and isolated components have shown a wide spectrum of in vitro and in vivo pharmacological activities like antidiabetic, anticonvulsant, antioxidant, anti-inflammatory, immunomodulatory, analgesic, antimicrobial, antiviral, antihypertensive, anticancer, antihyperglycemic, antinociceptive, gastroprotective, and wound healing activities. Conclusions. O. europaea emerged as a good source of traditional medicine for the treatment of various ailments. The outcomes of phytochemical and pharmacological studies reported in this review will further expand its existing therapeutic potential and provide a convincing support to its future clinical use in modern medicine. PMID:25802541

  14. Effects of Soil on Ammonia, Ethylene, Chloroethane, and 1,1,1-Trichloroethane Oxidation by Nitrosomonas europaea†

    PubMed Central

    Hommes, Norman G.; Russell, Sterling A.; Bottomley, Peter J.; Arp, Daniel J.

    1998-01-01

    Ammonia monooxygenase (AMO) from Nitrosomonas europaea catalyzes the oxidation of ammonia to hydroxylamine and has been shown to oxidize a variety of halogenated and nonhalogenated hydrocarbons. As part of a program focused upon extending these observations to natural systems, a study was conducted to examine the influence of soil upon the cooxidative abilities of N. europaea. Small quantities of Willamette silt loam (organic carbon content, 1.8%; cation-exchange capacity, 15 cmol/kg of soil) were suspended with N. europaea cells in a soil-slurry-type reaction mixture. The oxidations of ammonia and three different hydrocarbons (ethylene, chloroethane, and 1,1,1-trichloroethane) were compared to results for controls in which no soil was added. The soil significantly inhibited nitrite production from 10 mM ammonium by N. europaea. Inhibition resulted from a combination of ammonium adsorption onto soil colloids and the exchangeable acidity of the soil lowering the pH of the reaction mixture. These phenomena resulted in a substantial drop in the concentration of NH4+ in solution (10 to 4.5 mM) and, depending upon the pH, in a reduction in the amount of available NH3 to concentrations (8 to 80 μM) similar to the Ks value of AMO for NH3 (∼29 μM). At a fixed initial pH (7.8), the presence of soil also modified the rates of oxidation of ethylene and chloroethane and changed the concentrations at which their maximal rates of oxidation occurred. The modifying effects of soil on nitrite production and on the cooxidation of ethylene and chloroethane could be circumvented by raising the ammonium concentration in the reaction mixture from 10 to 50 mM. Soil had virtually no effect on the oxidation of 1,1,1-trichloroethane. PMID:16349541

  15. Media Effects on Nitrosomonas Europaea Monochloramine Disinfection Kinetics Using Propidium Monoazide Quantitative Real-time PCR

    EPA Science Inventory

    Monochloramine use as a secondary disinfectant in the United States is predicted to increase to 57% of all surface and 7% of all ground water systems. With monochloramine addition, there is a risk of nitrification in the distribution system by ammonia-oxidizing bacteria (AOB). Ni...

  16. Media Effects on Nitrosomonas Europaea Monochloramine Disinfection Kinetics Using Propidium Monoazide Quantitative Real-time PCR

    EPA Science Inventory

    Monochloramine use as a secondary disinfectant in the United States is predicted to increase to 57% of all surface and 7% of all ground water systems. With monochloramine addition, there is a risk of nitrification in the distribution system by ammonia-oxidizing bacteria (AOB). Ba...

  17. Assessing variability in gel-based proteomic analysis of Nitrosomonas europaea.

    PubMed

    Burton, Emily O; Hickey, William J

    2011-01-01

    Proteomics offers a unique look at the way protein expression changes in response to stimuli, and "gel-based" methods that utilize two-dimensional gel electrophoresis (2-DE) are key technologies in such studies. However, the many steps involved can be technically complex, and the resulting data are subject to variability from both technical and biological sources. Designing 2-DE proteomic studies can be challenging, as a set of standard methods or experimental designs has not been established. This being the case, it is especially important to identify and control sources of variability. Statistically significant results can be obtained if the experimental design includes a sufficient number of replicate 2-DE gels, and if the replicate gels are similar enough to be analyzed in the same experiment. While three or four replicates are often sufficient for compensation of variability, the pilot study illustrated in this chapter showed that statistically significant expression differences could be detected for 90% of the spots matched if six replicate experiments were done.

  18. Media effects on Nitrosomonas Europaea Monochloramine Disinfection Kinetics using Propidium Monoazide Quantitative Real-time PCR

    EPA Science Inventory

    Monochloramine use as a secondary disinfectant in the United States is predicted to increase to 57% of all surface and 7% of all ground water systems. With monochloramine addition, there is a risk of nitrification in the distribution system by ammonia-oxidizing bacteria (AOB). Ba...

  19. Hydroxylamine addition impact to Nitrosomonas europaea activity in the presence of monochloramine

    EPA Science Inventory

    In drinking water, monochloramine may promote ammonia–oxidizing bacteria (AOB) growth because of concurrent ammonia presence. AOB use (i) ammonia monooxygenase for biological ammonia oxidation to hydroxylamine and (ii) hydroxylamine oxidoreductase for hydroxylamine oxidation to ...

  20. Isolation and characterization of a thermotolerant ammonia-oxidizing bacterium Nitrosomonas sp. JPCCT2 from a thermal power station.

    PubMed

    Itoh, Yoshikane; Sakagami, Keiko; Uchino, Yoshihito; Boonmak, Chanita; Oriyama, Tetsuro; Tojo, Fuyumi; Matsumoto, Mitsufumi; Morikawa, Masaaki

    2013-01-01

    A thermotolerant ammonia-oxidizing bacterium strain JPCCT2 was isolated from activated sludge in a thermal power station. Cells of JPCCT2 are short non-motile rods or ellipsoidal. Molecular phylogenetic analysis of 16S rRNA gene sequences demonstrated that JPCCT2 belongs to the genus Nitrosomonas with the highest similarity to Nitrosomonas nitrosa Nm90 (100%), Nitrosomonas sp. Nm148 (99.7%), and Nitrosomonas communis Nm2 (97.7%). However, G+C content of JPCCT2 DNA was 49.1 mol% and clearly different from N. nitrosa Nm90, 47.9%. JPCCT2 was capable of growing at temperatures up to 48 °C, while N. nitrosa Nm90 and N. communis Nm2 could not grow at 42°C. Moreover, JPCCT2 grew similarly at concentrations of carbonate 0 and 5 gL(-1). This is the first report that Nitrosomonas bacterium is capable of growing at temperatures higher than 37°C.

  1. Isolation and Characterization of a Thermotolerant Ammonia-Oxidizing Bacterium Nitrosomonas sp. JPCCT2 from a Thermal Power Station

    PubMed Central

    Itoh, Yoshikane; Sakagami, Keiko; Uchino, Yoshihito; Boonmak, Chanita; Oriyama, Tetsuro; Tojo, Fuyumi; Matsumoto, Mitsufumi; Morikawa, Masaaki

    2013-01-01

    A thermotolerant ammonia-oxidizing bacterium strain JPCCT2 was isolated from activated sludge in a thermal power station. Cells of JPCCT2 are short non-motile rods or ellipsoidal. Molecular phylogenetic analysis of 16S rRNA gene sequences demonstrated that JPCCT2 belongs to the genus Nitrosomonas with the highest similarity to Nitrosomonas nitrosa Nm90 (100%), Nitrosomonas sp. Nm148 (99.7%), and Nitrosomonas communis Nm2 (97.7%). However, G+C content of JPCCT2 DNA was 49.1 mol% and clearly different from N. nitrosa Nm90, 47.9%. JPCCT2 was capable of growing at temperatures up to 48°C, while N. nitrosa Nm90 and N. communis Nm2 could not grow at 42°C. Moreover, JPCCT2 grew similarly at concentrations of carbonate 0 and 5 gL−1. This is the first report that Nitrosomonas bacterium is capable of growing at temperatures higher than 37°C. PMID:24256971

  2. Fauna Europaea – Orthopteroid orders

    PubMed Central

    Bohn, Horst; Haas, Fabian; Willemse, Fer

    2016-01-01

    Abstract Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant European terrestrial and freshwater animals, their geographical distribution at the level of countries and major islands (west of the Urals and excluding the Caucasus region), and some additional information. The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. The “Orthopteroid orders“ is one of the 58 Fauna Europaea major taxonomic groups. It contains series of mostly well-known insect orders: Embiodea (webspinners), Dermaptera (earwigs), Phasmatodea (walking sticks), Orthoptera s.s. (grasshoppers, crickets, bush-crickets) and Dictyoptera with the suborders Mantodea (mantids), Blattaria (cockroaches) and Isoptera (termites). For the Orthopteroid orders, data from 35 families containing 1,371 species are included in this paper. PMID:27660531

  3. Ecophysiology and Comparative Genomics of Nitrosomonas mobilis Ms1 Isolated from Autotrophic Nitrifying Granules of Wastewater Treatment Bioreactor.

    PubMed

    Thandar, Soe Myat; Ushiki, Norisuke; Fujitani, Hirotsugu; Sekiguchi, Yuji; Tsuneda, Satoshi

    2016-01-01

    Ammonia-oxidizing bacteria (AOB), which oxidize ammonia to nitrite in the first step of nitrification, play an important role in biological wastewater treatment systems. Nitrosomonas mobilis is an important and dominant AOB in various wastewater treatment systems. However, the detailed physiological and genomic properties of N. mobilis have not been thoroughly investigated because of limited success isolating pure cultures. This study investigated the key physiological characteristics of N. mobilis Ms1, which was previously isolated into pure culture from the nitrifying granules of wastewater treatment bioreactor. The pure culture of N. mobilis Ms1 was cultivated in liquid mineral medium with 30 mg-N L(-1) (2.14 mM) of ammonium at room temperature under dark conditions. The optimum growth of N. mobilis Ms1 occurred at 27°C and pH 8, with a maximum growth rate of 0.05-0.07 h(-1), which corresponded to a generation time of 10-14 h. The half saturation constant for ammonium uptake rate and the maximum ammonium uptake rate of N. mobilis Ms1 were 30.70 ± 0.51 μM NH4(+) and 0.01 ± 0.002 pmol NH4(+) cells(-1) h(-1), respectively. N. mobilis Ms1 had higher ammonia oxidation activity than N. europaea in this study. The oxygen uptake activity kinetics of N. mobilis Ms1 were Km(O2) = 21.74 ± 4.01 μM O2 and V max(O2) = 0.06 ± 0.02 pmol O2 cells(-1) h(-1). Ms1 grew well at ammonium and NaCl concentrations of up to 100 and 500 mM, respectively. The nitrite tolerance of N. mobilis Ms1 was extremely high (up to 300 mM) compared to AOB previously isolated from activated sludge and wastewater treatment plants. The average nucleotide identity between the genomes of N. mobilis Ms1 and other Nitrosomonas species indicated that N. mobilis Ms1 was distantly related to other Nitrosomonas species. The organization of the genes encoding protein inventory involved in ammonia oxidation and nitrifier denitrification processes were different from other Nitrosomonas species. The current

  4. Ecophysiology and Comparative Genomics of Nitrosomonas mobilis Ms1 Isolated from Autotrophic Nitrifying Granules of Wastewater Treatment Bioreactor

    PubMed Central

    Thandar, Soe Myat; Ushiki, Norisuke; Fujitani, Hirotsugu; Sekiguchi, Yuji; Tsuneda, Satoshi

    2016-01-01

    Ammonia-oxidizing bacteria (AOB), which oxidize ammonia to nitrite in the first step of nitrification, play an important role in biological wastewater treatment systems. Nitrosomonas mobilis is an important and dominant AOB in various wastewater treatment systems. However, the detailed physiological and genomic properties of N. mobilis have not been thoroughly investigated because of limited success isolating pure cultures. This study investigated the key physiological characteristics of N. mobilis Ms1, which was previously isolated into pure culture from the nitrifying granules of wastewater treatment bioreactor. The pure culture of N. mobilis Ms1 was cultivated in liquid mineral medium with 30 mg-N L-1 (2.14 mM) of ammonium at room temperature under dark conditions. The optimum growth of N. mobilis Ms1 occurred at 27°C and pH 8, with a maximum growth rate of 0.05–0.07 h-1, which corresponded to a generation time of 10–14 h. The half saturation constant for ammonium uptake rate and the maximum ammonium uptake rate of N. mobilis Ms1 were 30.70 ± 0.51 μM NH4+ and 0.01 ± 0.002 pmol NH4+ cells-1 h-1, respectively. N. mobilis Ms1 had higher ammonia oxidation activity than N. europaea in this study. The oxygen uptake activity kinetics of N. mobilis Ms1 were Km(O2) = 21.74 ± 4.01 μM O2 and V max(O2) = 0.06 ± 0.02 pmol O2 cells-1 h-1. Ms1 grew well at ammonium and NaCl concentrations of up to 100 and 500 mM, respectively. The nitrite tolerance of N. mobilis Ms1 was extremely high (up to 300 mM) compared to AOB previously isolated from activated sludge and wastewater treatment plants. The average nucleotide identity between the genomes of N. mobilis Ms1 and other Nitrosomonas species indicated that N. mobilis Ms1 was distantly related to other Nitrosomonas species. The organization of the genes encoding protein inventory involved in ammonia oxidation and nitrifier denitrification processes were different from other Nitrosomonas species. The current study

  5. Kinetic parameter estimation in N. europaea biofilms using a 2-D reactive transport model.

    PubMed

    Lauchnor, Ellen G; Semprini, Lewis; Wood, Brian D

    2015-06-01

    Biofilms of the ammonia oxidizing bacterium Nitrosomonas europaea were cultivated to study microbial processes associated with ammonia oxidation in pure culture. We explored the hypothesis that the kinetic parameters of ammonia oxidation in N. europaea biofilms were in the range of those determined with batch suspended cells. Oxygen and pH microelectrodes were used to measure dissolved oxygen (DO) concentrations and pH above and inside biofilms and reactive transport modeling was performed to simulate the measured DO and pH profiles. A two dimensional (2-D) model was used to simulate advection parallel to the biofilm surface and diffusion through the overlying fluid while reaction and diffusion were simulated in the biofilm. Three experimental studies of microsensor measurements were performed with biofilms: i) NH3 concentrations near the Ksn value of 40 μM determined in suspended cell tests ii) Limited buffering capacity which resulted in a pH gradient within the biofilms and iii) NH3 concentrations well below the Ksn value. Very good fits to the DO concentration profiles both in the fluid above and in the biofilms were achieved using the 2-D model. The modeling study revealed that the half-saturation coefficient for NH3 in N. europaea biofilms was close to the value measured in suspended cells. However, the third study of biofilms with low availability of NH3 deviated from the model prediction. The model also predicted shifts in the DO profiles and the gradient in pH that resulted for the case of limited buffering capacity. The results illustrate the importance of incorporating both key transport and chemical processes in a biofilm reactive transport model.

  6. Molecular studies in olive (Olea europaea L.): overview on DNA markers applications and recent advances in genome analysis.

    PubMed

    Bracci, T; Busconi, M; Fogher, C; Sebastiani, L

    2011-04-01

    Olive (Olea europaea L.) is one of the oldest agricultural tree crops worldwide and is an important source of oil with beneficial properties for human health. This emblematic tree crop of the Mediterranean Basin, which has conserved a very wide germplasm estimated in more than 1,200 cultivars, is a diploid species (2n = 2x = 46) that is present in two forms, namely wild (Olea europaea subsp. europaea var. sylvestris) and cultivated (Olea europaea subsp. europaea var. europaea). In spite of its economic and nutritional importance, there are few data about the genetic of olive if compared with other fruit crops. Available molecular data are especially related to the application of molecular markers to the analysis of genetic variability in Olea europaea complex and to develop efficient molecular tools for the olive oil origin traceability. With regard to genomic research, in the last years efforts are made for the identification of expressed sequence tag, with particular interest in those sequences expressed during fruit development and in pollen allergens. Very recently the sequencing of chloroplast genome provided new information on the olive nucleotide sequence, opening the olive genomic era. In this article, we provide an overview of the most relevant results in olive molecular studies. A particular attention was given to DNA markers and their application that constitute the most part of published researches. The first important results in genome analysis were reported.

  7. Fauna Europaea: Diptera – Brachycera

    PubMed Central

    Beuk, Paul; Pont, Adrian Charles; Shatalkin, Anatole I.; Ozerov, Andrey L.; Woźnica, Andrzej J.; Merz, Bernhard; Bystrowski, Cezary; Raper, Chris; Bergström, Christer; Kehlmaier, Christian; Clements, David K.; Greathead, David; Kameneva, Elena Petrovna; Nartshuk, Emilia; Petersen, Frederik T.; Weber, Gisela; Bächli, Gerhard; Geller-Grimm, Fritz; Van de Weyer, Guy; Tschorsnig, Hans-Peter; de Jong, Herman; van Zuijlen, Jan-Willem; Vaňhara, Jaromír; Roháček, Jindřich; Ziegler, Joachim; Majer, József; Hůrka, Karel; Holston, Kevin; Rognes, Knut; Greve-Jensen, Lita; Munari, Lorenzo; de Meyer, Marc; Pollet, Marc; Speight, Martin C. D.; Ebejer, Martin John; Martinez, Michel; Carles-Tolrá, Miguel; Földvári, Mihály; Chvála, Milan; Barták, Miroslav; Evenhuis, Neal L.; Chandler, Peter J.; Cerretti, Pierfilippo; Meier, Rudolf; Rozkosny, Rudolf; Prescher, Sabine; Gaimari, Stephen D.; Zatwarnicki, Tadeusz; Zeegers, Theo; Dikow, Torsten; Korneyev, Valery A.; Richter, Vera Andreevna; Michelsen, Verner; Tanasijtshuk, Vitali N.; Mathis, Wayne N.; Hubenov, Zdravko

    2015-01-01

    Abstract Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant multicellular European terrestrial and freshwater animals and their geographical distribution at the level of countries and major islands (east of the Urals and excluding the Caucasus region). The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing taxonomic specialists throughout Europe and is a unique (standard) reference suitable for many user communities in science, government, industry, nature conservation and education. The Diptera–Brachycera is one of the 58 Fauna Europaea major taxonomic groups, and data have been compiled by a network of 55 specialists. Within the two-winged insects (Diptera), the Brachycera constitute a monophyletic group, which is generally given rank of suborder. The Brachycera may be classified into the probably paraphyletic 'lower brachyceran grade' and the monophyletic Eremoneura. The latter contains the Empidoidea, the Apystomyioidea with a single Nearctic species, and the Cyclorrhapha, which in turn is divided into the paraphyletic 'aschizan grade' and the monophyletic Schizophora. The latter is traditionally divided into the paraphyletic 'acalyptrate grade' and the monophyletic Calyptratae. Our knowledge of the European fauna of Diptera–Brachycera varies tremendously among families, from the reasonably well known hoverflies (Syrphidae) to the extremely poorly known scuttle flies (Phoridae). There has been a steady growth in our knowledge of European Diptera for the last two centuries, with no apparent slow down, but there is a shift towards a larger fraction of the new species being found among the families of the nematoceran grade (lower Diptera), which due to a larger

  8. Fauna Europaea: Helminths (Animal Parasitic)

    PubMed Central

    Bray, Rodney A.; Hunt, David; Georgiev, Boyko B.; Scholz, Tomaš; Harris, Philip D.; Bakke, Tor A.; Pojmanska, Teresa; Niewiadomska, Katarzyna; Kostadinova, Aneta; Tkach, Vasyl; Bain, Odile; Durette-Desset, Marie-Claude; Gibbons, Lynda; Moravec, František; Petter, Annie; Dimitrova, Zlatka M.; Buchmann, Kurt; Valtonen, E. Tellervo; de Jong, Yde

    2014-01-01

    Abstract Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Helminths parasitic in animals represent a large assemblage of worms, representing three phyla, with more than 200 families and almost 4,000 species of parasites from all major vertebrate and many invertebrate groups. A general introduction is given for each of the major groups of parasitic worms, i.e. the Acanthocephala, Monogenea, Trematoda (Aspidogastrea and Digenea), Cestoda and Nematoda. Basic information for each group includes its size, host-range, distribution, morphological features, life-cycle, classification, identification and recent key-works. Tabulations include a complete list of families dealt with, the number of species in each and the name of the specialist responsible for data acquisition, a list of additional specialists who helped with particular groups, and a list of higher taxa dealt with down to the family level. A compilation of useful references is appended. PMID:25349520

  9. Fauna Europaea: Mollusca – Bivalvia

    PubMed Central

    2015-01-01

    Abstract Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. For the Mollusca-Bivalvia, data from 5 families (Margaritiferidae, Unionidae, Sphaeriidae, Cyrenidae, Dreissenidae) containing 55 species are included in this paper. European freshwater bivalves belong to the Orders Unionoida and Cardiida. All the European unionoids are included in the superfamily Unionoidea, the freshwater mussels or naiads. The European cardiids belong to the following three superfamilies: Cardioidea, Cyrenoidea and Dreissenoidea. Among the Unionoidea there are the most imperilled animal groups on the planet while the Cardioidea includes the cosmopolitan genus Pisidium, the Cyrenoidea the Asiatic clam (Corbicula fluminea) and the Dreissenoidea the famous invasive zebra mussel (Dreissena polymorpha). Basic information is summarized on their taxonomy and biology. Tabulations include a complete list of the current estimated families, genera and species. PMID:26311403

  10. Fauna europaea: helminths (animal parasitic).

    PubMed

    Gibson, David I; Bray, Rodney A; Hunt, David; Georgiev, Boyko B; Scholz, Tomaš; Harris, Philip D; Bakke, Tor A; Pojmanska, Teresa; Niewiadomska, Katarzyna; Kostadinova, Aneta; Tkach, Vasyl; Bain, Odile; Durette-Desset, Marie-Claude; Gibbons, Lynda; Moravec, František; Petter, Annie; Dimitrova, Zlatka M; Buchmann, Kurt; Valtonen, E Tellervo; de Jong, Yde

    2014-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Helminths parasitic in animals represent a large assemblage of worms, representing three phyla, with more than 200 families and almost 4,000 species of parasites from all major vertebrate and many invertebrate groups. A general introduction is given for each of the major groups of parasitic worms, i.e. the Acanthocephala, Monogenea, Trematoda (Aspidogastrea and Digenea), Cestoda and Nematoda. Basic information for each group includes its size, host-range, distribution, morphological features, life-cycle, classification, identification and recent key-works. Tabulations include a complete list of families dealt with, the number of species in each and the name of the specialist responsible for data acquisition, a list of additional specialists who helped with particular groups, and a list of higher taxa dealt with down to the family level. A compilation of useful references is appended.

  11. Dictyophara europaea (Hemiptera: Fulgoromorpha: Dictyopharidae): description of immatures, biology and host plant associations.

    PubMed

    Krstić, O; Cvrković, T; Mitrović, M; Toševski, I; Jović, J

    2016-06-01

    The European lantern fly Dictyophara europaea (Linnaeus, 1767), is a polyphagous dictyopharid planthopper of Auchenorrhyncha commonly found throughout the Palaearctic. Despite abundant data on its distribution range and reports on its role in the epidemiology of plant-pathogenic phytoplasmas (Flavescence dorée, FD-C), literature regarding the biology and host plants of this species is scarce. Therefore, the aims of our study were to investigate the seasonal occurrence, host plant associations, oviposition behaviour and immature stages of this widespread planthopper of economic importance. We performed a 3-year field study to observe the spatio-temporal distribution and feeding sources of D. europaea. The insects's reproductive strategy, nymphal molting and behaviour were observed under semi-field cage conditions. Measurement of the nymphal vertex length was used to determine the number of instars, and the combination of these data with body length, number of pronotal rows of sensory pits and body colour pattern enabled the discrimination of each instar. We provide data showing that D. europaea has five instars with one generation per year and that it overwinters in the egg stage. Furthermore, our study confirmed highly polyphagous feeding nature of D. europaea, for all instars and adults, as well as adult horizontal movement during the vegetation growing season to the temporarily preferred feeding plants where they aggregate during dry season. We found D. europaea adult aggregation in late summer on Clematis vitalba L. (Ranunculaceae), a reservoir plant of FD-C phytoplasma strain; however, this appears to be a consequence of forced migration due to drying of herbaceous vegetation rather than to a high preference of C. vitalba as a feeding plant. Detailed oviposition behaviour and a summary of the key discriminatory characteristics of the five instars are provided. Emphasis is placed on the economic importance of D. europaea because of its involvement in

  12. Monochloramine disinfection kinetics of Nitrosomonas europaea using propidium monoazide quantitative real-time PCR (PMA-qPCR)

    EPA Science Inventory

    As a result of the implementation of the Stage 1 and Stage 2 Disinfectants and Disinfection Byproduct Rules, monochloramine use as a secondary disinfectant in the United States is predicted to increase to 57% of all surface and 7% of all ground water treatment systems. In additi...

  13. Yeast functional screen to identify genes conferring salt stress tolerance in Salicornia europaea

    PubMed Central

    Nakahara, Yoshiki; Sawabe, Shogo; Kainuma, Kenta; Katsuhara, Maki; Shibasaka, Mineo; Suzuki, Masanori; Yamamoto, Kosuke; Oguri, Suguru; Sakamoto, Hikaru

    2015-01-01

    Salinity is a critical environmental factor that adversely affects crop productivity. Halophytes have evolved various mechanisms to adapt to saline environments. Salicornia europaea L. is one of the most salt-tolerant plant species. It does not have special salt-secreting structures like a salt gland or salt bladder, and is therefore a good model for studying the common mechanisms underlying plant salt tolerance. To identify candidate genes encoding key proteins in the mediation of salt tolerance in S. europaea, we performed a functional screen of a cDNA library in yeast. The library was screened for genes that allowed the yeast to grow in the presence of 1.3 M NaCl. We obtained three full-length S. europaea genes that confer salt tolerance. The genes are predicted to encode (1) a novel protein highly homologous to thaumatin-like proteins, (2) a novel coiled-coil protein of unknown function, and (3) a novel short peptide of 32 residues. Exogenous application of a synthetic peptide corresponding to the 32 residues improved salt tolerance of Arabidopsis. The approach described in this report provides a rapid assay system for large-scale screening of S. europaea genes involved in salt stress tolerance and supports the identification of genes responsible for such mechanisms. These genes may be useful candidates for improving crop salt tolerance by genetic transformation. PMID:26579166

  14. Fauna Europaea: Neuropterida (Raphidioptera, Megaloptera, Neuroptera)

    PubMed Central

    2015-01-01

    Abstract Fauna Europaea provides a public web-service with an index of scientific names of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. For Neuropterida, data from three Insect orders (Raphidioptera, Megaloptera, Neuroptera), comprising 15 families and 397 species, are included. PMID:25941450

  15. Fauna europaea: neuropterida (raphidioptera, megaloptera, neuroptera).

    PubMed

    Aspöck, Ulrike; Aspöck, Horst; Letardi, Agostino; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. For Neuropterida, data from three Insect orders (Raphidioptera, Megaloptera, Neuroptera), comprising 15 families and 397 species, are included.

  16. Fauna Europaea: Hymenoptera - Apocrita (excl. Ichneumonoidea).

    PubMed

    Mitroiu, Mircea-Dan; Noyes, John; Cetkovic, Aleksandar; Nonveiller, Guido; Radchenko, Alexander; Polaszek, Andrew; Ronquist, Fredrick; Forshage, Mattias; Pagliano, Guido; Gusenleitner, Josef; Bartalucci, Mario Boni; Olmi, Massimo; Fusu, Lucian; Madl, Michael; Johnson, Norman F; Jansta, Petr; Wahis, Raymond; Soon, Villu; Rosa, Paolo; Osten, Till; Barbier, Yvan; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Hymenoptera is one of the four largest orders of insects, with about 130,000 described species. In the Fauna Europaea database, 'Hymenoptera - Apocrita (excluding Ichneumonoidea)' comprises 13 superfamilies, 52 families, 91 subfamilies, 38 tribes and 13,211 species. The paper includes a complete list of taxa dealt with, the number of species in each and the name of the specialist responsible for data acquisition. As a general conclusion about the European fauna of Hymenoptera, the best known countries in terms of recorded species are those from northwestern Europe, with the least known fauna probably in the more eastern and southeastern parts of Europe.

  17. Prevalence of Nitrosomonas cluster 7 populations in the ammonia-oxidizing community of a submerged membrane bioreactor treating urban wastewater under different operation conditions.

    PubMed

    Cerrone, F; Poyatos, J M; Molina-Muñoz, M; Cortés-Lorenzo, C; González-López, J; Rodelas, B

    2013-07-01

    A pilot-scale ultrafiltration membrane bioreactor (MBR) was used for the aerobic treatment of urban wastewater in four experimental stages influenced by seasonal temperature and different sets of operation conditions. The structure of the ammonia-oxidizing bacteria (AOB) community was profiled by temperature gradient gel electrophoresis (TGGE), based on the amplification and separation of partial ammonia-monoxygenase subunit A (amoA) genes. Canonical correspondence analysis revealed that temperature, hydraulic retention time and percentage of ammonia removal had a significant effect on the fingerprints of AOB communities. Phylogenetic analysis conducted on amoA/AmoA sequences of reamplified TGGE bands showed, however, that closely related ammonia-oxidizing populations inhabited the sludge of the MBR in all experimental stages. Nitrosomonas cluster 7 populations (N. europaea-N. eutropha cluster) prevailed under all conditions tested, even when the MBR was operated under complete biomass retention or at low temperatures, suggesting that the high ammonia concentrations in the system were determinant to select r-strategist AOB.

  18. Somatic Embryogenesis in Olive (Olea europaea L. subsp. europaea var. sativa and var. sylvestris).

    PubMed

    Rugini, Eddo; Silvestri, Cristian

    2016-01-01

    Protocols for olive somatic embryogenesis from zygotic embryos and mature tissues have been described for both Olea europaea sub. europaea var. sativa and var. sylvestris. Immature zygotic embryos (no more than 75 days old), used after fruit collection or stored at 12-14 °C for 2-3 months, are the best responsive explants and very slightly genotype dependent, and one single protocol can be effective for a wide range of genotypes. On the contrary, protocols for mature zygotic embryos and for mature tissue of cultivars are often genotype specific, so that they may require many adjustments according to genotypes. The use of thidiazuron and cefotaxime seems to be an important trigger for induction phase particularly for tissues derived from cultivars. Up to now, however, the application of this technique for large-scale propagation is hampered also by the low rate of embryo germination; it proves nonetheless very useful for genetic improvement.

  19. Fauna Europaea - all European animal species on the web.

    PubMed

    de Jong, Yde; Verbeek, Melina; Michelsen, Verner; Bjørn, Per de Place; Los, Wouter; Steeman, Fedor; Bailly, Nicolas; Basire, Claire; Chylarecki, Przemek; Stloukal, Eduard; Hagedorn, Gregor; Wetzel, Florian Tobias; Glöckler, Falko; Kroupa, Alexander; Korb, Günther; Hoffmann, Anke; Häuser, Christoph; Kohlbecker, Andreas; Müller, Andreas; Güntsch, Anton; Stoev, Pavel; Penev, Lyubomir

    2014-01-01

    Fauna Europaea is Europe's main zoological taxonomic index, making the scientific names and distributions of all living, currently known, multicellular, European land and freshwater animals species integrally available in one authoritative database. Fauna Europaea covers about 260,000 taxon names, including 145,000 accepted (sub)species, assembled by a large network of (>400) leading specialists, using advanced electronic tools for data collations with data quality assured through sophisticated validation routines. Fauna Europaea started in 2000 as an EC funded FP5 project and provides a unique taxonomic reference for many user-groups such as scientists, governments, industries, nature conservation communities and educational programs. Fauna Europaea was formally accepted as an INSPIRE standard for Europe, as part of the European Taxonomic Backbone established in PESI. Fauna Europaea provides a public web portal at faunaeur.org with links to other key biodiversity services, is installed as a taxonomic backbone in wide range of biodiversity services and actively contributes to biodiversity informatics innovations in various initiatives and EC programs.

  20. Fauna Europaea – all European animal species on the web

    PubMed Central

    Verbeek, Melina; Michelsen, Verner; Bjørn, Per de Place; Los, Wouter; Steeman, Fedor; Bailly, Nicolas; Basire, Claire; Chylarecki, Przemek; Stloukal, Eduard; Hagedorn, Gregor; Wetzel, Florian Tobias; Glöckler, Falko; Kroupa, Alexander; Korb, Günther; Hoffmann, Anke; Häuser, Christoph; Kohlbecker, Andreas; Müller, Andreas; Güntsch, Anton; Stoev, Pavel; Penev, Lyubomir

    2014-01-01

    Abstract Fauna Europaea is Europe's main zoological taxonomic index, making the scientific names and distributions of all living, currently known, multicellular, European land and freshwater animals species integrally available in one authoritative database. Fauna Europaea covers about 260,000 taxon names, including 145,000 accepted (sub)species, assembled by a large network of (>400) leading specialists, using advanced electronic tools for data collations with data quality assured through sophisticated validation routines. Fauna Europaea started in 2000 as an EC funded FP5 project and provides a unique taxonomic reference for many user-groups such as scientists, governments, industries, nature conservation communities and educational programs. Fauna Europaea was formally accepted as an INSPIRE standard for Europe, as part of the European Taxonomic Backbone established in PESI. Fauna Europaea provides a public web portal at faunaeur.org with links to other key biodiversity services, is installed as a taxonomic backbone in wide range of biodiversity services and actively contributes to biodiversity informatics innovations in various initiatives and EC programs. PMID:25349527

  1. Development of the plerocercoid I of Ophiotaenia europaea in reptiles.

    PubMed

    Biserkov, V; Kostadinova, A

    1997-12-01

    The existence of a two-host life-cycle in ophiotaeniid proteocephalideans was tested experimentally using Ophiotaenia europaea as a model. Three species of reptiles, Natrix natrix, Natrix tessellata and Lacerta viridis, were fed with experimentally infected copepods containing a large number of infective plerocercoids I. A few plerocercoids, most of which were dead, corresponding morphologically to the plerocercoid II developmental stage of O. europaea, were found encysted in the intestinal wall of N. natrix (8 days p.i.), N. tessellata (5 and 150 days p.i.) and L. viridis (40 days p.i.), while no plerocercoids or adult worms were recovered from their intestines. The results indicate that the infective plerocercoid I of O. europaea cannot undergo further development when ingested directly by the final host (a reptile), and that environmental temperature stimuli cannot initiate a reverse plerocercoid migration to the gut followed by strobilization.

  2. Ammonia-Oxidizing Bacteria in Biofilters Removing Trihalomethanes Are Related to Nitrosomonas oligotropha ▿

    PubMed Central

    Wahman, David G.; Kirisits, Mary Jo; Katz, Lynn E.; Speitel, Gerald E.

    2011-01-01

    Ammonia-oxidizing bacteria (AOB) in nitrifying biofilters degrading four regulated trihalomethanes—trichloromethane, bromodichloromethane, dibromochloromethane, and tribromomethane—were related to Nitrosomonas oligotropha. N. oligotropha is associated with chloraminated drinking water systems, and its presence in the biofilters might indicate that trihalomethane tolerance is another reason that this bacterium is dominant in chloraminated systems. PMID:21278264

  3. Proteome Regulation during Olea europaea Fruit Development

    PubMed Central

    Bianco, Linda; Alagna, Fiammetta; Baldoni, Luciana; Finnie, Christine; Svensson, Birte; Perrotta, Gaetano

    2013-01-01

    Background Widespread in the Mediterranean basin, Olea europaea trees are gaining worldwide popularity for the nutritional and cancer-protective properties of the oil, mechanically extracted from ripe fruits. Fruit development is a physiological process with remarkable impact on the modulation of the biosynthesis of compounds affecting the quality of the drupes as well as the final composition of the olive oil. Proteomics offers the possibility to dig deeper into the major changes during fruit development, including the important phase of ripening, and to classify temporal patterns of protein accumulation occurring during these complex physiological processes. Methodology/Principal Findings In this work, we started monitoring the proteome variations associated with olive fruit development by using comparative proteomics coupled to mass spectrometry. Proteins extracted from drupes at three different developmental stages were separated on 2-DE and subjected to image analysis. 247 protein spots were revealed as differentially accumulated. Proteins were identified from a total of 121 spots and discussed in relation to olive drupe metabolic changes occurring during fruit development. In order to evaluate if changes observed at the protein level were consistent with changes of mRNAs, proteomic data produced in the present work were compared with transcriptomic data elaborated during previous studies. Conclusions/Significance This study identifies a number of proteins responsible for quality traits of cv. Coratina, with particular regard to proteins associated to the metabolism of fatty acids, phenolic and aroma compounds. Proteins involved in fruit photosynthesis have been also identified and their pivotal contribution in oleogenesis has been discussed. To date, this study represents the first characterization of the olive fruit proteome during development, providing new insights into fruit metabolism and oil accumulation process. PMID:23349718

  4. Multiple compartmentalization of sodium conferred salt tolerance in Salicornia europaea.

    PubMed

    Lv, Sulian; Jiang, Ping; Chen, Xianyang; Fan, Pengxiang; Wang, Xuchu; Li, Yinxin

    2012-02-01

    Euhalophyte Salicornia europaea L., one of the most salt-tolerant plant species in the world, can tolerate more than 1000 mM NaCl. To study the salt tolerance mechanism of this plant, the effects of different NaCl concentrations on plant growth, as well as Na(+) accumulation and distribution at organ, tissue, and subcellular levels, were investigated. Optimal growth and an improved photosynthetic rate were observed with the plant treated with 200-400 mM NaCl. The Na(+) content in the shoots was considerably higher than that in the roots of S. europaea. The Na(+) in S. europaea cells may act as an effective osmotic adjuster to maintain cell turgor, promoting photosynthetic competence and plant growth. The results from the SEM-X-ray and TEM-X-ray microanalyses demonstrate that Na(+) was compartmentalized predominantly into the cell vacuoles of shoot endodermis tissues. Accordingly, the transcript amounts of SeNHX1, SeVHA-A, and SeVP1 increased significantly with increased NaCl concentration, suggesting their important roles in Na(+) sequestration into the vacuoles. Therefore, a multiple sodium compartmentalization mechanism is proposed to enhance further the salt tolerance of S. europaea.

  5. Antimicrobial potential of green synthesized CeO2 nanoparticles from Olea europaea leaf extract

    PubMed Central

    Maqbool, Qaisar; Nazar, Mudassar; Naz, Sania; Hussain, Talib; Jabeen, Nyla; Kausar, Rizwan; Anwaar, Sadaf; Abbas, Fazal; Jan, Tariq

    2016-01-01

    This article reports the green fabrication of cerium oxide nanoparticles (CeO2 NPs) using Olea europaea leaf extract and their applications as effective antimicrobial agents. O. europaea leaf extract functions as a chelating agent for reduction of cerium nitrate. The resulting CeO2 NPs exhibit pure single-face cubic structure, which is examined by X-ray diffraction, with a uniform spherical shape and a mean size 24 nm observed through scanning electron microscopy and transmission electron microscopy. Ultraviolet-visible spectroscopy confirms the characteristic absorption peak of CeO2 NPs at 315 nm. Fourier transform infrared spectroscopy reflects stretching frequencies at 459 cm−1, showing utilization of natural components for the production of NPs. Thermal gravimetric analysis predicts the successful capping of CeO2 NPs by bioactive molecules present in the plant extract. The antimicrobial studies show significant zone of inhibition against bacterial and fungal strains. The higher activities shown by the green synthesized NPs than the plant extract lead to the conclusion that they can be effectively used in biomedical application. Furthermore, reduction of cerium salt by plant extract will reduce environmental impact over chemical synthesis. PMID:27785011

  6. Antimicrobial potential of green synthesized CeO2 nanoparticles from Olea europaea leaf extract.

    PubMed

    Maqbool, Qaisar; Nazar, Mudassar; Naz, Sania; Hussain, Talib; Jabeen, Nyla; Kausar, Rizwan; Anwaar, Sadaf; Abbas, Fazal; Jan, Tariq

    This article reports the green fabrication of cerium oxide nanoparticles (CeO2 NPs) using Olea europaea leaf extract and their applications as effective antimicrobial agents. O. europaea leaf extract functions as a chelating agent for reduction of cerium nitrate. The resulting CeO2 NPs exhibit pure single-face cubic structure, which is examined by X-ray diffraction, with a uniform spherical shape and a mean size 24 nm observed through scanning electron microscopy and transmission electron microscopy. Ultraviolet-visible spectroscopy confirms the characteristic absorption peak of CeO2 NPs at 315 nm. Fourier transform infrared spectroscopy reflects stretching frequencies at 459 cm(-1), showing utilization of natural components for the production of NPs. Thermal gravimetric analysis predicts the successful capping of CeO2 NPs by bioactive molecules present in the plant extract. The antimicrobial studies show significant zone of inhibition against bacterial and fungal strains. The higher activities shown by the green synthesized NPs than the plant extract lead to the conclusion that they can be effectively used in biomedical application. Furthermore, reduction of cerium salt by plant extract will reduce environmental impact over chemical synthesis.

  7. Fauna Europaea: Annelida - Hirudinea, incl. Acanthobdellea and Branchiobdellea.

    PubMed

    Minelli, Alessandro; Sket, Boris; de Jong, Yde

    2014-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Hirudinea is a fairly small group of Annelida, with about 680 described species, most of which live in freshwater habitats, but several species are (sub)terrestrial or marine. In the Fauna Europaea database the taxon is represented by 87 species in 6 families. Two closely related groups, currently treated as distinct lineages within the Annelida, are the Acanthobdellea (2 species worldwide, of which 1 in Europe) and the Branchiobdellea (about 140 species worldwide, of which 10 in Europe). This paper includes a complete list of European taxa belonging to the Hirudinea, Acanthobdellea and Branchiobdellea. Recent research on a limited number of taxa suggests that our current appreciation of species diversity of Hirudinea in Europe is still provisional: on the one hand, cryptic, unrecognised taxa are expected to emerge; on the other, the status of some taxa currently treated as distinct species deserves revisiting.

  8. Molecular characterization of genetic diversity, structure, and differentiation in the olive (Olea europaea L.) germplasm collection of the united states department of agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fifteen microsatellite loci were used to genotype 108 accessions of cultivated olive, Olea europaea L. ssp. europaea var. europaea, and eight of O. europaea L. ssp. cuspidata (Wall. ex G. Don) Ciferri from the germplasm collection of the United States Department of Agriculture in Davis, California. ...

  9. Complete genome sequence of Nitrosomonas sp. Is79, an ammonia oxidizing bacterium adapted to low ammonium concentrations

    PubMed Central

    Bollmann, Annette; Sedlacek, Christopher J.; Norton, Jeanette; Laanbroek, Hendrikus J.; Suwa, Yuichi; Stein, Lisa Y.; Klotz, Martin G.; Arp, Daniel; Sayavedra-Soto, Luis; Lu, Megan; Bruce, David; Detter, Chris; Tapia, Roxanne; Han, James; Woyke, Tanja; Lucas, Susan M.; Pitluck, Sam; Pennacchio, Len; Nolan, Matt; Land, Miriam L.; Huntemann, Marcel; Deshpande, Shweta; Han, Cliff; Chen, Amy; Kyrpides, Nikos; Mavromatis, Konstantinos; Markowitz, Victor; Szeto, Ernest; Ivanova, Natalia; Mikhailova, Natalia; Pagani, Ioanna; Pati, Amrita; Peters, Lin; Ovchinnikova, Galina; Goodwin, Lynne A.

    2013-01-01

    Nitrosomonas sp. Is79 is a chemolithoautotrophic ammonia-oxidizing bacterium that belongs to the family Nitrosomonadaceae within the phylum Proteobacteria. Ammonia oxidation is the first step of nitrification, an important process in the global nitrogen cycle ultimately resulting in the production of nitrate. Nitrosomonas sp. Is79 is an ammonia oxidizer of high interest because it is adapted to low ammonium and can be found in freshwater environments around the world. The 3,783,444-bp chromosome with a total of 3,553 protein coding genes and 44 RNA genes was sequenced by the DOE-Joint Genome Institute Program CSP 2006. PMID:24019993

  10. Complete genome sequence of Nitrosomonas sp. Is79, an ammonia oxidizing bacterium adapted to low ammonium concentrations

    SciTech Connect

    Bollmann, Annette; Sedlacek, Christopher J; Laanbroek, Hendrikus J; Suwa, Yuichi; Stein, Lisa Y; Klotz, Martin G; Arp, D J; Sayavedra-Soto, LA; Lu, Megan; Bruce, David; Detter, J. Chris; Tapia, Roxanne; Han, James; Woyke, Tanja; Lucas, Susan; Pitluck, Sam; Pennacchio, Len; Nolan, Matt; Land, Miriam L; Huntemann, Marcel; Deshpande, Shweta; Han, Cliff; Chen, Amy; Kyrpides, Nikos C; Mavromatis, K; Markowitz, Victor; Szeto, Ernest; Ivanova, N; Mikhailova, Natalia; Pagani, Ioanna; Pati, Amrita; Peters, Lin; Ovchinnikova, Galina; Goodwin, Lynne A.

    2013-01-01

    Nitrosomonas sp. Is79 is a chemolithoautotrophic ammonia-oxidizing bacterium that belongs to the family Nitrosomonadaceae within the phylum Proteobacteria. Ammonia oxidation is the first step of nitrification, an important process in the global nitrogen cycle ultimately resulting in the production of nitrate. Nitrosomonas sp. Is79 is an ammonia oxidizer of high interest because it is adapted to low ammonium and can be found in freshwater environments around the world. The 3,783,444-bp chromosome with a total of 3,553 protein coding genes and 44 RNA genes was sequenced by the DOE-Joint Genome Institute Program CSP 2006.

  11. Isolation of Endophytic Plant Growth-Promoting Bacteria Associated with the Halophyte Salicornia europaea and Evaluation of their Promoting Activity Under Salt Stress.

    PubMed

    Zhao, Shuai; Zhou, Na; Zhao, Zheng-Yong; Zhang, Ke; Wu, Guo-Hua; Tian, Chang-Yan

    2016-10-01

    Several reports have highlighted that many plant growth-promoting endophytic bacteria (PGPE) can assist their host plants in coping with various biotic and abiotic stresses. However, information about the PGPE colonizing in the halophytes is still scarce. This study was designed to isolate and characterize PGPE from salt-accumulating halophyte Salicornia europaea grown under extreme salinity and to evaluate in vitro the bacterial mechanisms related to plant growth promotion. A total of 105 isolates were obtained from the surface-sterilized roots, stems, and assimilation twigs of S. europaea. Thirty-two isolates were initially selected for their ability to produce 1-aminocyclopropane-1-carboxylate deaminase as well as other properties such as production of indole-3-acetic acid and phosphate-solubilizing activities. The 16S rRNA gene-sequencing analysis revealed that these isolates belong to 13 different genera and 19 bacterial species. For these 32 strains, seed germination and seedling growth in axenically grown S. europaea seedlings at different NaCl concentrations (50-500 mM) were quantified. Five isolates possessing significant stimulation of the host plant growth were obtained. The five isolates were identified as Bacillus endophyticus, Bacillus tequilensis, Planococcus rifietoensis, Variovorax paradoxus, and Arthrobacter agilis. All the five strains could colonize and can be reisolated from the host plant interior tissues. These results demonstrate that habitat-adapted PGPE isolated from halophyte could enhance plant growth under saline stress conditions.

  12. Comparative evaluation of Melissa officinalis L., Tilia europaea L., Passiflora edulis Sims. and Hypericum perforatum L. in the elevated plus maze anxiety test.

    PubMed

    Coleta, M; Campos, M G; Cotrim, M D; Proença da Cunha, A

    2001-07-01

    There are numerous plants that have been used for their 'tranquillising' properties in Portuguese folk medicine. This report will describe a comparative analysis of the effects of Melissa officinalis L., Tilia europaea L., Passiflora edulis Sims. and Hypericum perforatum L. on the performance of mice in the elevated plus maze, open-field, and horizontal-wire tests. We have tested lyophilised aqueous extracts with doses ranging from 5-100 mg/kg prepared according to traditional folk medicine. The results indicate that Hypericum perforatum L. and Tilia europaea L. induced significant raise in immobility time, diminution of rearing and other parameters, suggesting a clear sedative effect at doses ranging from 10-100 mg/kg. Below these doses, Tilia europaea L. did not induce any significant change in the tests mentioned, while Hypericum perforatum L. (5 mg/kg) increased the time spent in the open areas of the elevated plus maze and the percentage of unprotected head-dips and stretch-approach postures, thus indicating an anxiolytic effect. For this dose, there were no significant changes in motor activity as measured by classical parameters for the tests used. As the infused H. perforatum L. tested was devoid of hyperforin, it can be stated that the observed effects cannot be attributed to this substance.

  13. Complete Genome Sequence of Nitrosomonas cryotolerans ATCC 49181, a Phylogenetically Distinct Ammonia-Oxidizing Bacterium Isolated from Arctic Waters.

    PubMed

    Rice, Marlen C; Norton, Jeanette M; Stein, Lisa Y; Kozlowski, Jessica; Bollmann, Annette; Klotz, Martin G; Sayavedra-Soto, Luis; Shapiro, Nicole; Goodwin, Lynne A; Huntemann, Marcel; Clum, Alicia; Pillay, Manoj; Varghese, Neha; Mikhailova, Natalia; Palaniappan, Krishna; Ivanova, Natalia; Mukherjee, Supratim; Reddy, T B K; Yee Ngan, Chew; Daum, Chris; Kyrpides, Nikos; Woyke, Tanja

    2017-03-16

    Nitrosomonas cryotolerans ATCC 49181 is a cold-tolerant marine ammonia-oxidizing bacterium isolated from seawater collected in the Gulf of Alaska. The high-quality complete genome contains a 2.87-Mbp chromosome and a 56.6-kbp plasmid. Chemolithoautotrophic modules encoding ammonia oxidation and CO2 fixation were identified.

  14. Nitrosomonas stercoris sp. nov., a Chemoautotrophic Ammonia-Oxidizing Bacterium Tolerant of High Ammonium Isolated from Composted Cattle Manure

    PubMed Central

    Nakagawa, Tatsunori; Takahashi, Reiji

    2015-01-01

    Among ammonia-oxidizing bacteria, Nitrosomonas eutropha-like microbes are distributed in strongly eutrophic environments such as wastewater treatment plants and animal manure. In the present study, we isolated an ammonia-oxidizing bacterium tolerant of high ammonium levels, designated strain KYUHI-ST, from composted cattle manure. Unlike the other known Nitrosomonas species, this isolate grew at 1,000 mM ammonium. Phylogenetic analyses based on 16S rRNA and amoA genes indicated that the isolate belonged to the genus Nitrosomonas and formed a unique cluster with the uncultured ammonia oxidizers found in wastewater systems and animal manure composts, suggesting that these ammonia oxidizers contributed to removing higher concentrations of ammonia in strongly eutrophic environments. Based on the physiological and phylogenetic data presented here, we propose and call for the validation of the provisional taxonomic assignment Nitrosomonas stercoris, with strain KYUHI-S as the type strain (type strain KYUHI-ST = NBRC 110753T = ATCC BAA-2718T). PMID:26156554

  15. Complete Genome Sequence of Nitrosomonas cryotolerans ATCC 49181, a Phylogenetically Distinct Ammonia-Oxidizing Bacterium Isolated from Arctic Waters

    PubMed Central

    Rice, Marlen C.; Stein, Lisa Y.; Kozlowski, Jessica; Bollmann, Annette; Sayavedra-Soto, Luis; Shapiro, Nicole; Goodwin, Lynne A.; Huntemann, Marcel; Clum, Alicia; Pillay, Manoj; Varghese, Neha; Mikhailova, Natalia; Palaniappan, Krishna; Ivanova, Natalia; Mukherjee, Supratim; Reddy, T. B. K.; Yee Ngan, Chew; Daum, Chris; Kyrpides, Nikos; Woyke, Tanja

    2017-01-01

    ABSTRACT Nitrosomonas cryotolerans ATCC 49181 is a cold-tolerant marine ammonia-oxidizing bacterium isolated from seawater collected in the Gulf of Alaska. The high-quality complete genome contains a 2.87-Mbp chromosome and a 56.6-kbp plasmid. Chemolithoautotrophic modules encoding ammonia oxidation and CO2 fixation were identified. PMID:28302769

  16. Effects of Bacterial Community Members on the Proteome of the Ammonia-Oxidizing Bacterium Nitrosomonas sp. Strain Is79

    PubMed Central

    Sedlacek, Christopher J.; Nielsen, Susanne; Greis, Kenneth D.; Haffey, Wendy D.; Revsbech, Niels Peter; Ticak, Tomislav; Laanbroek, Hendrikus J.

    2016-01-01

    ABSTRACT Microorganisms in the environment do not exist as the often-studied pure cultures but as members of complex microbial communities. Characterizing the interactions within microbial communities is essential to understand their function in both natural and engineered environments. In this study, we investigated how the presence of a nitrite-oxidizing bacterium (NOB) and heterotrophic bacteria affect the growth and proteome of the chemolithoautotrophic ammonia-oxidizing bacterium (AOB) Nitrosomonas sp. strain Is79. We investigated Nitrosomonas sp. Is79 in co-culture with Nitrobacter winogradskyi, in co-cultures with selected heterotrophic bacteria, and as a member of the nitrifying enrichment culture G5-7. In batch culture, N. winogradskyi and heterotrophic bacteria had positive effects on the growth of Nitrosomonas sp. Is79. An isobaric tag for relative and absolute quantification (iTRAQ) liquid chromatography-tandem mass spectrometry (LC-MS/MS) proteomics approach was used to investigate the effect of N. winogradskyi and the co-cultured heterotrophic bacteria from G5-7 on the proteome of Nitrosomonas sp. Is79. In co-culture with N. winogradskyi, several Nitrosomonas sp. Is79 oxidative stress response proteins changed in abundance, with periplasmic proteins increasing and cytoplasmic proteins decreasing in abundance. In the presence of heterotrophic bacteria, the abundance of proteins directly related to the ammonia oxidation pathway increased, while the abundance of proteins related to amino acid synthesis and metabolism decreased. In summary, the proteome of Nitrosomonas sp. Is79 was differentially influenced by the presence of either N. winogradskyi or heterotrophic bacteria. Together, N. winogradskyi and heterotrophic bacteria reduced the oxidative stress for Nitrosomonas sp. Is79, which resulted in more efficient metabolism. IMPORTANCE Aerobic ammonia-oxidizing microorganisms play an important role in the global nitrogen cycle, converting ammonia to

  17. Antimicrobial activity of commercial Olea europaea (olive) leaf extract.

    PubMed

    Sudjana, Aurelia N; D'Orazio, Carla; Ryan, Vanessa; Rasool, Nooshin; Ng, Justin; Islam, Nabilah; Riley, Thomas V; Hammer, Katherine A

    2009-05-01

    The aim of this research was to investigate the activity of a commercial extract derived from the leaves of Olea europaea (olive) against a wide range of microorganisms (n=122). Using agar dilution and broth microdilution techniques, olive leaf extract was found to be most active against Campylobacter jejuni, Helicobacter pylori and Staphylococcus aureus [including meticillin-resistant S. aureus (MRSA)], with minimum inhibitory concentrations (MICs) as low as 0.31-0.78% (v/v). In contrast, the extract showed little activity against all other test organisms (n=79), with MICs for most ranging from 6.25% to 50% (v/v). In conclusion, olive leaf extract was not broad-spectrum in action, showing appreciable activity only against H. pylori, C. jejuni, S. aureus and MRSA. Given this specific activity, olive leaf extract may have a role in regulating the composition of the gastric flora by selectively reducing levels of H. pylori and C. jejuni.

  18. Metabolomic Functional Analysis of Bacterial Genomes: Final Report

    SciTech Connect

    Arp, Daniel J; Sayavedra-Soto, Luis A

    2008-01-01

    The availability of the complete DNA sequence of the bacterial genome of Nitrosomonas europaea offered the opportunity for unprecedented and detailed investigations of function. We studied the function of genes involved in carbohydrate and Fe metabolism. N. europaea has genes for the synthesis and degradation of glycogen and sucrose but cannot grow on substrates other than ammonia and CO2. Granules of glycogen were detected in whole cells by electron microscopy and quantified in cell-free extracts by enzymatic methods. The cellular glycogen and sucrose content varied depending on the composition of the growth medium and cellular growth stage. N. europaea also depends heavily on iron for metabolism of ammonia, is particularly interesting since it lacks genes for siderophore production, and has genes with only low similarity to known iron reductases, yet grows relatively well in medium containing low Fe. By comparing the transcriptomes of cells grown in iron-replete medium versus iron-limited medium, 247 genes were identified as differentially expressed. Mutant strains deficient in genes for sucrose, glycogen and iron metabolism were created and are being used to further our understanding of ammonia oxidizing bacteria.

  19. Modeling the low pH limit of Nitrosomonas eutropha in high-strength nitrogen wastewaters.

    PubMed

    Fumasoli, Alexandra; Morgenroth, Eberhard; Udert, Kai M

    2015-10-15

    In wastewater treatment, the rate of ammonia oxidation decreases with pH and stops very often slightly below a pH of 6. Free ammonia (NH3) limitation, inhibition by nitrous acid (HNO2), limitation by inorganic carbon or direct effect of high proton concentrations have been proposed to cause the rate decrease with pH as well as the cessation of ammonia oxidation. In this study, we compare an exponential pH term common for food microbiology with conventionally applied rate laws based on Monod-type kinetics for NH3 limitation and non-competitive HNO2 inhibition as well as sigmoidal pH functions to model the low pH limit of ammonia oxidizing bacteria (AOB). For this purpose we conducted well controlled batch experiments which were then simulated with a computer model. The results showed that kinetics based on NH3 limitation and HNO2 inhibition can explain the rate decrease of ammonia oxidation between pH 7 and 6, but fail in predicting the pH limit of Nitrosomonas eutropha at pH 5.4 and rates close to that limit. This is where the exponential pH term becomes important: this term decreases the rate of ammonia oxidation to zero, as the pH limit approaches. Previously proposed sigmoidal pH functions that affect large pH regions, however, led to an overestimation of the pH effect and could therefore not be applied successfully. We show that the proposed exponential pH term can be explained quantitatively with thermodynamic principles: at low pH values, the energy available from the proton motive force is too small for the NADH production in Nitrosomonas eutropha and related AOB causing an energy limited state of the bacterial cell. Hence, energy limitation and not inhibition or limitation of enzymes is responsible for the cessation of the AOB activity at low pH values.

  20. Conveyor Cultivation of the Halophytic Plant Salicornia europaea for the Recycling of NaCl from Human Liquid Waste in a Biological Life Support System.

    NASA Astrophysics Data System (ADS)

    Balnokin, Yurii; Myasoedov, Nikolay; Popova, Larissa; Tikhomirov, Alexander A.; Ushakova, Sofya; Tikhomirova, Natalia; Lasseur, Christophe; Gros, Jean-Bernard

    One problem in designing bioregenerative life support systems (BLSS) is developing technolo-gies to include human liquid and solid waste in intrasystem recycling. A specific task is recycling of NaCl excreted in urine by humans. We showed recently that this could be achieved through inclusion of the salt accumulating halophyte Salicornia europaea in the autotrophic compart-ment of the BLSS (Balnokin et al., ASR, 2010, in press). A model of NaCl circulation in BLSS with inclusion of S. europaea was based on the NaCl turnover in the human -urine -nutrient solution -S. europaea -human cycle. Mineralized urine was used as a basis for preparation of a nutrient solution for the halophyte cultivation. The shoots of the halophyte cultivated in the mineralized urine and containing NaCl could to be used by the BLSS inhabitants in their diets. In this report we describe cultivation of S. europaea which allows turnover of NaCl and produces daily shoot biomass containing Na+ and Cl- in quantities approximately equal to those excreted in daily human urine. The plants were grown in water culture in a climatic chamber under controlled conditions. A solution simulating mineralized urine (SSMU) was used as a basis for preparation of a nutri-ent solution for S. europaea cultivation. For continuous biomass production, seedlings of S. europaea, germinated preliminary in moist sand, were being transferred to the nutrient solu-tion at regular intervals (every two days). Duration of the conveyor operation was 112 days. During the first 56 days, the seedlings were being planted in SSMU diluted by a factor of 1.5 (2/3 SSMU). The same solution was introduced into the growth vessels as volumes of growth medium decreased due to plant transpiration. Starting from the 56th day as conveyor operation was initiated, the plants were being harvested every two days; the solutions from the discharged vessels were mixed with the fresh SSMU and the mixture was introduced into all other growth vessels of

  1. Possibility of Salicornia europaea use for the human liquid wastes inclusion into BLSS intrasystem mass exchange

    NASA Astrophysics Data System (ADS)

    Tikhomirova, Natalia A.; Ushakova, Sofya A.; Tikhomirov, Alexander A.; Kalacheva, Galina S.; Gros, Jean-Bernard

    One of the ways of solving the problem of the human liquid wastes utilization in bioregenerative life support systems (BLSS) can be the use of halophytic vegetable plant Salicornia europaea capable of accumulating sodium chloride in rather high concentrations. Since the most specific higher plant function in BLSS, which at present cannot be substituted by physicochemical processes, appears to be the biosynthesis of a wide spectrum of nutritive substances necessary for a human, the object of the given work was the investigation of the S. europaea productivity, biochemical and mineral composition when grown under close to optimal BLSS vegetative component conditions. As the use of human urine after its preliminary physicochemical processing is supposed to be the mineral solution basis for the S. europaea cultivation, it is necessary to clear up the effect of reduced nitrogen on plants growth. Ground research was carried out. Biochemical composition of the S. europaea edible part showed that crude protein was contained in the highest degree. At that the content of crude protein (24% per dry weight) and cellulose (4.7% per dry weight) was higher in the plants grown on solutions containing amide nitrogen in comparison with the plants grown on solutions with nitrate nitrogen (15.4%—3.1% correspondingly). The water-soluble sugar contents were not high in the S. europaea edible part and depending on the nitrogen nutrition form they amounted to 1.1% (amide nitrogen) and 1.5% (nitrate nitrogen). The polysaccharide number (except cellulose) was rather higher and varied from 7.7% to 8.2%. Although the lipid content in the S. europaea plants was relatively low (7% per dry weight), it was shown that the plant lipids are characterized by a high nonsaturation degree mainly due to alpha linolenic and linoleic acids. Nitrogen nutrition form did not significantly affect the S. europaea productivity, and dry edible biomass of one plant was 8.6 g. Sodium and its concentrations

  2. The Peculiar Landscape of Repetitive Sequences in the Olive (Olea europaea L.) Genome

    PubMed Central

    Barghini, Elena; Natali, Lucia; Cossu, Rosa Maria; Giordani, Tommaso; Pindo, Massimo; Cattonaro, Federica; Scalabrin, Simone; Velasco, Riccardo; Morgante, Michele; Cavallini, Andrea

    2014-01-01

    Analyzing genome structure in different species allows to gain an insight into the evolution of plant genome size. Olive (Olea europaea L.) has a medium-sized haploid genome of 1.4 Gb, whose structure is largely uncharacterized, despite the growing importance of this tree as oil crop. Next-generation sequencing technologies and different computational procedures have been used to study the composition of the olive genome and its repetitive fraction. A total of 2.03 and 2.3 genome equivalents of Illumina and 454 reads from genomic DNA, respectively, were assembled following different procedures, which produced more than 200,000 differently redundant contigs, with mean length higher than 1,000 nt. Mapping Illumina reads onto the assembled sequences was used to estimate their redundancy. The genome data set was subdivided into highly and medium redundant and nonredundant contigs. By combining identification and mapping of repeated sequences, it was established that tandem repeats represent a very large portion of the olive genome (∼31% of the whole genome), consisting of six main families of different length, two of which were first discovered in these experiments. The other large redundant class in the olive genome is represented by transposable elements (especially long terminal repeat-retrotransposons). On the whole, the results of our analyses show the peculiar landscape of the olive genome, related to the massive amplification of tandem repeats, more than that reported for any other sequenced plant genome. PMID:24671744

  3. 454 Pyrosequencing of Olive (Olea europaea L.) Transcriptome in Response to Salinity

    PubMed Central

    Bazakos, Christos; Manioudaki, Maria E.; Sarropoulou, Elena; Spano, Thodhoraq; Kalaitzis, Panagiotis

    2015-01-01

    Olive (Olea europaea L.) is one of the most important crops in the Mediterranean region. The expansion of cultivation in areas irrigated with low quality and saline water has negative effects on growth and productivity however the investigation of the molecular basis of salt tolerance in olive trees has been only recently initiated. To this end, we investigated the molecular response of cultivar Kalamon to salinity stress using next-generation sequencing technology to explore the transcriptome profile of olive leaves and roots and identify differentially expressed genes that are related to salt tolerance response. Out of 291,958 obtained trimmed reads, 28,270 unique transcripts were identified of which 35% are annotated, a percentage that is comparable to similar reports on non-model plants. Among the 1,624 clusters in roots that comprise more than one read, 24 were differentially expressed comprising 9 down- and 15 up-regulated genes. Respectively, inleaves, among the 2,642 clusters, 70 were identified as differentially expressed, with 14 down- and 56 up-regulated genes. Using next-generation sequencing technology we were able to identify salt-response-related transcripts. Furthermore we provide an annotated transcriptome of olive as well as expression data, which are both significant tools for further molecular studies in olive. PMID:26576008

  4. The peculiar landscape of repetitive sequences in the olive (Olea europaea L.) genome.

    PubMed

    Barghini, Elena; Natali, Lucia; Cossu, Rosa Maria; Giordani, Tommaso; Pindo, Massimo; Cattonaro, Federica; Scalabrin, Simone; Velasco, Riccardo; Morgante, Michele; Cavallini, Andrea

    2014-04-01

    Analyzing genome structure in different species allows to gain an insight into the evolution of plant genome size. Olive (Olea europaea L.) has a medium-sized haploid genome of 1.4 Gb, whose structure is largely uncharacterized, despite the growing importance of this tree as oil crop. Next-generation sequencing technologies and different computational procedures have been used to study the composition of the olive genome and its repetitive fraction. A total of 2.03 and 2.3 genome equivalents of Illumina and 454 reads from genomic DNA, respectively, were assembled following different procedures, which produced more than 200,000 differently redundant contigs, with mean length higher than 1,000 nt. Mapping Illumina reads onto the assembled sequences was used to estimate their redundancy. The genome data set was subdivided into highly and medium redundant and nonredundant contigs. By combining identification and mapping of repeated sequences, it was established that tandem repeats represent a very large portion of the olive genome (∼31% of the whole genome), consisting of six main families of different length, two of which were first discovered in these experiments. The other large redundant class in the olive genome is represented by transposable elements (especially long terminal repeat-retrotransposons). On the whole, the results of our analyses show the peculiar landscape of the olive genome, related to the massive amplification of tandem repeats, more than that reported for any other sequenced plant genome.

  5. 454 Pyrosequencing of Olive (Olea europaea L.) Transcriptome in Response to Salinity.

    PubMed

    Bazakos, Christos; Manioudaki, Maria E; Sarropoulou, Elena; Spano, Thodhoraq; Kalaitzis, Panagiotis

    2015-01-01

    Olive (Olea europaea L.) is one of the most important crops in the Mediterranean region. The expansion of cultivation in areas irrigated with low quality and saline water has negative effects on growth and productivity however the investigation of the molecular basis of salt tolerance in olive trees has been only recently initiated. To this end, we investigated the molecular response of cultivar Kalamon to salinity stress using next-generation sequencing technology to explore the transcriptome profile of olive leaves and roots and identify differentially expressed genes that are related to salt tolerance response. Out of 291,958 obtained trimmed reads, 28,270 unique transcripts were identified of which 35% are annotated, a percentage that is comparable to similar reports on non-model plants. Among the 1,624 clusters in roots that comprise more than one read, 24 were differentially expressed comprising 9 down- and 15 up-regulated genes. Respectively, inleaves, among the 2,642 clusters, 70 were identified as differentially expressed, with 14 down- and 56 up-regulated genes. Using next-generation sequencing technology we were able to identify salt-response-related transcripts. Furthermore we provide an annotated transcriptome of olive as well as expression data, which are both significant tools for further molecular studies in olive.

  6. Characterization of antioxidant enzymes and peroxisomes of olive (Olea europaea L.) fruits.

    PubMed

    Lopez-Huertas, Eduardo; del Río, Luis A

    2014-10-15

    The presence of peroxisomes in olive (Olea europaea L.) fruits and different antioxidant enzymes occurring in this plant tissue is reported for the first time. Ultrastructural analysis showed that olive cells were characterized by the presence of large vacuoles and lipid drops. Plastids, mitochondria and peroxisomes were placed near the cell wall, showing some type of association with it. Olive fruit peroxisomes were purified by sucrose density-gradient centrifugation, and catalase, glutathione reductase and ascorbate peroxidase were found in peroxisomes. In olive fruit tissue the presence of a battery of antioxidant enzymes was demonstrated, including catalase, four superoxide dismutase isozymes (mainly an Fe-SOD plus 2 Cu,Zn-SOD and a Mn-SOD), all the enzymes of the ascorbate-glutathione cycle, reduced and oxidized glutathione, ascorbate, and four NADPH-recycling dehydrogenases. The knowledge of the full composition of antioxidants (enzymatic and non-enzymatic) in olive fruits is crucial to be able to understand the processes regulating the antioxidant composition of olive oil.

  7. Neighboring Deschampsia flexuosa and Trientalis europaea harbor contrasting root fungal endophytic communities.

    PubMed

    Tejesvi, Mysore V; Sauvola, Tiina; Pirttilä, Anna Maria; Ruotsalainen, Anna Liisa

    2013-01-01

    Fungal endophytic communities and potential host preference of root-inhabiting fungi of boreal forest understory plants are poorly known. The objective of this study was to find out whether two neighboring plant species, Deschampsia flexuosa (Poaceae) and Trientalis europaea (Primulaceae), share similar root fungal endophytic communities and whether the communities differ between two sites. The study was carried out by analysis of pure culture isolates and root fungal colonization percentages. A total of 84 isolates from D. flexuosa and 27 isolates from T. europaea were obtained. The roots of D. flexuosa harbored 16 different isolate types based on macromorphological characteristics, whereas only 4 isolate types were found in T. europaea. The root colonization by dark septate and hyaline septate hyphae correlated with isolate numbers being higher in D. flexuosa compared to T. europaea. The different isolate types were further identified on the basis of internal transcribed spacer sequence and phylogenetic analysis. An isolate type identified as dark septate endophyte Phialocephala fortinii colonized 50 % of the T. europaea and 21 % of the D. flexuosa specimens. In addition, Meliniomyces variabilis, Phialocephala sphaeroides, and Umbelopsis isabellina were found colonizing the grass, D. flexuosa, for the first time and Mycena sp. was confirmed as an endophyte of D. flexuosa. Site-specific differences were observed in the abundance and diversity of endophytic fungi in the roots of both study plants, but the differences were not as predominant as those between plant species. It is concluded that D. flexuosa harbors both higher amount and more diverse community of endophytic fungi in its roots compared to T. europaea.

  8. Olive plants (Olea europaea L.) as a bioindicator for pollution.

    PubMed

    Eliwa, Amal Mohamed; Kamel, Ehab Abdel-Razik

    2013-06-15

    In the present work, olive plant (Olea europaea L.) was used as a biological indicator for pollution in which, molecular and physiological parameters were studied. Olive plants were collected from polluted and non-polluted areas in Jeddah - Saudi Arabia, traffic area as an air polluted area, sewage treatment station as water polluted area, industrial area as solid waste polluted, costal area as marine polluted area and an area without a direct source of pollution far away from the city center, which was used as control. These changes conducted with nucleic acid content, minerals content, pigments and some growth parameters. Results showed significant reductions in DNA and RNA contents under all polluted sites. Mineral contents were varied widely depending on the different pollutants and locations of olive plant. Generally, micro-elements varied (increase/decrease) significantly within collected samples and the source of pollution. All growth parameters were decreased significantly within the studied samples of all pollutant areas except the relative water content was increased. The content of chlorophyll a has decreased highly significantly in all polluted leaves. While the content of chlorophyll b has increased significantly in all polluted leaves especially in air polluted leaves. The total content of carotenoid pigments has decreased highly significantly in all polluted leaves. It was concluded that olive plant can be used as a biological indicator to the environmental pollutants.

  9. Volatile constituents of commercial imported and domestic black-ripe table olives (Olea europaea)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Volatile constituents of commercial black-ripe table olives (Olea europaea) from the United States, Spain, Egypt and Morocco were analyzed by gas chromatography and gas chromatography-mass spectrometry (GC-MS). Dynamic headspace sampling was used to isolate a variety of aldehydes, alcohols, esters, ...

  10. Whole-Genome Sequence of a Novel Hantavirus Isolated from the European Mole (Talpa europaea)

    PubMed Central

    Gu, Se Hun; Hejduk, Janusz; Markowski, Janusz; Markowski, Marcin; Liberski, Paweł P.

    2015-01-01

    The complete genome sequence of Nova virus, a novel hantavirus isolated from a European mole (Talpa europaea) captured in central Poland, was determined. The availability of this sequence will facilitate the search for other mole-borne hantaviruses and will accelerate the acquisition of new knowledge about their phylogeography and evolutionary origin. PMID:26021917

  11. Characterization of Libyan olive, olea europaea L., cultivars using morpholigical data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Olive (Olea europaea L.) consumption and production are important socially and economically in Libya. Olive cultivars that are adapted to local conditions produce olives that have high quality and quantities of oil. Many of the important Libyan olive cultivars were included in this research. One goa...

  12. Headspace volatile composition of the flowers of Caralluma europaea N.E.Br. (Apocynaceae).

    PubMed

    Formisano, Carmen; Senatore, Felice; Della Porta, Giovanna; Scognamiglio, Mariarosa; Bruno, Maurizio; Maggio, Antonella; Rosselli, Sergio; Zito, Pietro; Sajeva, Maurizio

    2009-11-11

    The volatile constituents of the flowers of Caralluma europaea (Guss.) N.E.Br (Apocynaceae) from Lampedusa Island were analyzed by a headspace GC method. The analyses allowed the identification and quantification of 41 compounds. The main components were, among the monoterpenoids, terpinolene (23.3%), alpha-terpinene (19.1%) and linalool (18.4%), whereas, among the carbonylic compounds the major constituents were heptanal (2.0%), octanoic acid (2.4%) and hexanoic acid (1.7%). The presence of a nitrogen containing compound, indole (0.8%) and of a sulphur containing compound, dimethylsulphide (t), noteworthy. The compounds found in the flowers of C. europaea have been compared with data available in the literature as regard to their odor, presence in other sapromyiophilous taxa, possible role as semiochemicals, and presence in decaying organic matter. 89.3% of total constituents have been described in other sapromyiophilous taxa. Some of the compounds are present in several types of decaying organic matter (excrements, decomposing bodies, and spoiled fish, etc). Several volatiles found in C. europaea flowers are used as semiochemicals by Hymenoptera, Coleoptera, Diptera, Lepidoptera and other insects. Sixteen volatiles, accounting for 32.4% of the total constituents, are described as attractants of some Diptera families, with a biology linked to decaying organic matter. Our data thus confirm that C. europaea floral bouquet falls within the sapromyiophilous pollination syndrome.

  13. High-Throughput Sequencing of RNA Silencing-Associated Small RNAs in Olive (Olea europaea L.)

    PubMed Central

    Donaire, Livia; Pedrola, Laia; de la Rosa, Raúl; Llave, César

    2011-01-01

    Small RNAs (sRNAs) of 20 to 25 nucleotides (nt) in length maintain genome integrity and control gene expression in a multitude of developmental and physiological processes. Despite RNA silencing has been primarily studied in model plants, the advent of high-throughput sequencing technologies has enabled profiling of the sRNA component of more than 40 plant species. Here, we used deep sequencing and molecular methods to report the first inventory of sRNAs in olive (Olea europaea L.). sRNA libraries prepared from juvenile and adult shoots revealed that the 24-nt class dominates the sRNA transcriptome and atypically accumulates to levels never seen in other plant species, suggesting an active role of heterochromatin silencing in the maintenance and integrity of its large genome. A total of 18 known miRNA families were identified in the libraries. Also, 5 other sRNAs derived from potential hairpin-like precursors remain as plausible miRNA candidates. RNA blots confirmed miRNA expression and suggested tissue- and/or developmental-specific expression patterns. Target mRNAs of conserved miRNAs were computationally predicted among the olive cDNA collection and experimentally validated through endonucleolytic cleavage assays. Finally, we use expression data to uncover genetic components of the miR156, miR172 and miR390/TAS3-derived trans-acting small interfering RNA (tasiRNA) regulatory nodes, suggesting that these interactive networks controlling developmental transitions are fully operational in olive. PMID:22140484

  14. Bacterial Toxicity and Metabolism of Three Hydrazine Fuels.

    DTIC Science & Technology

    1980-09-01

    34 Journal of Bacteriology, 115, 480-485. 22. Nicholas, D.J. and Jones, O.T., 1960, "Oxidation of Hydroxylamine in Cell-Free Extracts of Nitrosomonas Europaea ...34 Nature, 185, 512. 23. Rees, M.K., 1968, "Studies of the Hydroxylamine Metabolism of Nitrosomonas Europaea : I. Purification of Hydroxylamine Oxidase...Intermediate in Nitrification," Nature, 169, 156-157. 55. Yoshida, T. and Alexander, M., 1964, "Hydroxylamine Formation by Nitrosomonas Europaea

  15. Proteomic platform for the identification of proteins in olive (Olea europaea) pulp.

    PubMed

    Capriotti, Anna Laura; Cavaliere, Chiara; Foglia, Patrizia; Piovesana, Susy; Samperi, Roberto; Stampachiacchiere, Serena; Laganà, Aldo

    2013-10-24

    The nutritional and cancer-protective properties of the oil extracted mechanically from the ripe fruits of Olea europaea trees are attracting constantly more attention worldwide. The preparation of high-quality protein samples from plant tissues for proteomic analysis poses many challenging problems. In this study we employed a proteomic platform based on two different extraction methods, SDS and CHAPS based protocols, followed by two precipitation protocols, TCA/acetone and MeOH precipitation, in order to increase the final number of identified proteins. The use of advanced MS techniques in combination with the Swissprot and NCBI Viridiplantae databases and TAIR10 Arabidopsis database allowed us to identify 1265 proteins, of which 22 belong to O. europaea. The application of this proteomic platform for protein extraction and identification will be useful also for other proteomic studies on recalcitrant plant/fruit tissues.

  16. Comparative cytogenetics of moles (Eulipotyphla, Talpidae): chromosomal differences in Talpa romana and T. europaea.

    PubMed

    Gornung, E; Volleth, M; Capanna, E; Castiglia, R

    2008-01-01

    The genus Talpa is the most specious and widespread one in the family Talpidae. The existing karyological records are predominantly basic morphological descriptions. To further investigate the case in point, we performed a comparative cytogenetic study in the genus by comparing G- and C-chromosome banding and NOR patterns of the two European species, T. romana and T. europaea, along with available data regarding several other mole species. Chromosomal hybridization patterns for telomeric repeats and major and 5S ribosomal RNA genes were obtained in T. romana and T. europaea for the first time. The comparison of these patterns revealed differences in distribution of interstitial telomeric repeats and 5S ribosomal RNA genes in the two species with apparently identical karyotypes but different evolutionary histories.

  17. Fauna Europaea: Coleoptera 2 (excl. series Elateriformia, Scarabaeiformia, Staphyliniformia and superfamily Curculionoidea).

    PubMed

    Audisio, Paolo; Alonso Zarazaga, Miguel-Angel; Slipinski, Adam; Nilsson, Anders; Jelínek, Josef; Taglianti, Augusto Vigna; Turco, Federica; Otero, Carlos; Canepari, Claudio; Kral, David; Liberti, Gianfranco; Sama, Gianfranco; Nardi, Gianluca; Löbl, Ivan; Horak, Jan; Kolibac, Jiri; Háva, Jirí; Sapiejewski, Maciej; Jäch, Manfred; Bologna, Marco Alberto; Biondi, Maurizio; Nikitsky, Nikolai B; Mazzoldi, Paolo; Zahradnik, Petr; Wegrzynowicz, Piotr; Constantin, Robert; Gerstmeier, Roland; Zhantiev, Rustem; Fattorini, Simone; Tomaszewska, Wioletta; Rücker, Wolfgang H; Vazquez-Albalate, Xavier; Cassola, Fabio; Angelini, Fernando; Johnson, Colin; Schawaller, Wolfgang; Regalin, Renato; Baviera, Cosimo; Rocchi, Saverio; Cianferoni, Fabio; Beenen, Ron; Schmitt, Michael; Sassi, David; Kippenberg, Horst; Zampetti, Marcello Franco; Trizzino, Marco; Chiari, Stefano; Carpaneto, Giuseppe Maria; Sabatelli, Simone; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Coleoptera represent a huge assemblage of holometabolous insects, including as a whole more than 200 recognized families and some 400,000 described species worldwide. Basic information is summarized on their biology, ecology, economic relevance, and estimated number of undescribed species worldwide. Little less than 30,000 species are listed from Europe. The Coleoptera 2 section of the Fauna Europaea database (Archostemata, Myxophaga, Adephaga and Polyphaga excl. the series Elateriformia, Scarabaeiformia, Staphyliniformia and the superfamily Curculionoidea) encompasses 80 families (according to the previously accepted family-level systematic framework) and approximately 13,000 species. Tabulations included a complete list of the families dealt with, the number of species in each, the names of all involved specialists, and, when possible, an estimate of the gaps in terms of total number of species at an European level. A list of some recent useful references is appended. Most families included in the Coleoptera 2 Section have been updated in the most recent release of the Fauna Europaea index, or are ready to be updated as soon as the FaEu data management environment completes its migration from Zoological Museum Amsterdam to Berlin Museum für Naturkunde.

  18. Fauna Europaea: Coleoptera 2 (excl. series Elateriformia, Scarabaeiformia, Staphyliniformia and superfamily Curculionoidea)

    PubMed Central

    Alonso Zarazaga, Miguel-Angel; Slipinski, Adam; Nilsson, Anders; Jelínek, Josef; Taglianti, Augusto Vigna; Turco, Federica; Otero, Carlos; Canepari, Claudio; Kral, David; Liberti, Gianfranco; Sama, Gianfranco; Nardi, Gianluca; Löbl, Ivan; Horak, Jan; Kolibac, Jiri; Háva, Jirí; Sapiejewski, Maciej; Jäch, Manfred; Bologna, Marco Alberto; Biondi, Maurizio; Nikitsky, Nikolai B.; Mazzoldi, Paolo; Zahradnik, Petr; Wegrzynowicz, Piotr; Constantin, Robert; Gerstmeier, Roland; Zhantiev, Rustem; Fattorini, Simone; Tomaszewska, Wioletta; Rücker, Wolfgang H.; Vazquez-Albalate, Xavier; Cassola, Fabio; Angelini, Fernando; Johnson, Colin; Schawaller, Wolfgang; Regalin, Renato; Baviera, Cosimo; Rocchi, Saverio; Cianferoni, Fabio; Beenen, Ron; Schmitt, Michael; Sassi, David; Kippenberg, Horst; Zampetti, Marcello Franco; Trizzino, Marco; Chiari, Stefano; Carpaneto, Giuseppe Maria; Sabatelli, Simone

    2015-01-01

    Abstract Fauna Europaea provides a public web-service with an index of scientific names (including synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. Coleoptera represent a huge assemblage of holometabolous insects, including as a whole more than 200 recognized families and some 400,000 described species worldwide. Basic information is summarized on their biology, ecology, economic relevance, and estimated number of undescribed species worldwide. Little less than 30,000 species are listed from Europe. The Coleoptera 2 section of the Fauna Europaea database (Archostemata, Myxophaga, Adephaga and Polyphaga excl. the series Elateriformia, Scarabaeiformia, Staphyliniformia and the superfamily Curculionoidea) encompasses 80 families (according to the previously accepted family-level systematic framework) and approximately 13,000 species. Tabulations included a complete list of the families dealt with, the number of species in each, the names of all involved specialists, and, when possible, an estimate of the gaps in terms of total number of species at an European level. A list of some recent useful references is appended. Most families included in the Coleoptera 2 Section have been updated in the most recent release of the Fauna Europaea index, or are ready to be updated as soon as the FaEu data management environment completes its migration from Zoological Museum Amsterdam to Berlin Museum für Naturkunde

  19. Fauna Europaea: Annelida - Terrestrial Oligochaeta (Enchytraeidae and Megadrili), Aphanoneura and Polychaeta

    PubMed Central

    2015-01-01

    Abstract Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. This paper provides updated information on the taxonomic composition and distribution of the Annelida - terrestrial Oligochaeta (Megadrili and Enchytraeidae), Aphanoneura and Polychaeta, recorded in Europe. Data on 18 families, 11 autochthonous and 7 allochthonous, represented in our continent by a total of 800 species, are reviewed, beginning from their distinctness, phylogenetic status, diversity and global distribution, and following with major recent developments in taxonomic and faunistic research in Europe. A rich list of relevant references is appended. The Fauna Europaea Annelida - terrestrial Oligochaeta data-set, as completed in 2004, will be updated accordingly. PMID:26379463

  20. Fauna Europaea: Annelida - Terrestrial Oligochaeta (Enchytraeidae and Megadrili), Aphanoneura and Polychaeta.

    PubMed

    Rota, Emilia; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all living European land and freshwater animals, their geographical distribution at country level (up to the Urals, excluding the Caucasus region), and some additional information. The Fauna Europaea project covers about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. This represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. This paper provides updated information on the taxonomic composition and distribution of the Annelida - terrestrial Oligochaeta (Megadrili and Enchytraeidae), Aphanoneura and Polychaeta, recorded in Europe. Data on 18 families, 11 autochthonous and 7 allochthonous, represented in our continent by a total of 800 species, are reviewed, beginning from their distinctness, phylogenetic status, diversity and global distribution, and following with major recent developments in taxonomic and faunistic research in Europe. A rich list of relevant references is appended. The Fauna Europaea Annelida - terrestrial Oligochaeta data-set, as completed in 2004, will be updated accordingly.

  1. Short communication: Promotion of glucagon-like peptide-2 secretion in dairy calves with a bioactive extract from Olea europaea.

    PubMed

    Morrison, S Y; Pastor, J J; Quintela, J C; Holst, J J; Hartmann, B; Drackley, J K; Ipharraguerre, I R

    2017-03-01

    Diarrhea episodes in dairy calves involve profound alterations in the mechanism controlling gut barrier function that ultimately compromise intestinal permeability to macromolecules, including pathogenic bacteria. Intestinal dysfunction models suggest that a key element of intestinal adaptation during the neonatal phase is the nutrient-induced secretion of glucagon-like peptide (GLP)-2 and associated effects on mucosal cell proliferation, barrier function, and inflammatory response. Bioactive molecules found in Olea europaea have been shown to induce the release of regulatory peptides from model enteroendocrine cells. The ability to enhance GLP-2 secretion via the feeding of putative GLP-2 secretagogues is untested in newborn calves. The objectives of this study were to determine whether feeding a bioactive extract from Olea europaea (OBE) mixed in the milk replacer (1) can stimulate GLP-2 secretion beyond the response elicited by enteral nutrients and, thereby, (2) improve intestinal permeability and animal growth as well as (3) reduce the incidence of diarrhea in preweaning dairy calves. Holstein heifer calves (n = 60) were purchased, transported to the research facility, and blocked by body weight and total serum protein and assigned to 1 of 3 treatments. Treatments were control (CON), standard milk replacer (MR) and ad libitum starter; CON plus OBE added into MR at 30 mg/kg of body weight (OBE30); and CON plus OBE added into MR at 60 mg/kg of body weight (OBE60). The concentration of GLP-2 was measured at the end of wk 2. Intestinal permeability was measured at the onset of the study and the end of wk 2 and 6, with lactulose and d-mannitol as markers. Treatments did not affect calf growth and starter intake. Compared with CON, administration of OBE60 increased the nutrient-induced response in GLP-2 by about 1 fold and reduced MR intake during the second week of study. Throughout the study, however, all calves had compromised intestinal permeability and a high

  2. Histochemical location of key enzyme activities involved in receptivity and self-incompatibility in the olive tree (Olea europaea L.).

    PubMed

    Serrano, Irene; Olmedilla, Adela

    2012-12-01

    Stigma-surface and style enzymes are important for pollen reception, selection and germination. This report deals with the histochemical location of the activity of four basic types of enzyme involved in these processes in the olive (Olea europaea L.). The detection of peroxidase, esterase and acid-phosphatase activities at the surface of the stigma provided evidence of early receptivity in olive pistils. The stigma maintained its receptivity until the arrival of pollen. Acid-phosphatase activity appeared in the style at the moment of anthesis and continued until the fertilization of the ovule. RNase activity was detected in the extracellular matrix of the styles of flowers just before pollination and became especially evident in pistils after self-pollination. This activity gradually decreased until it practically disappeared in more advanced stages. RNase activity was also detected in pollen tubes growing in pollinated pistils and appeared after in vitro germination in the presence of self-incompatible pistils. These findings suggest that RNases may well be involved in intraspecific pollen rejection in olive flowers. To the best of our knowledge this is the first time that evidence of enzyme activity in stigma receptivity and pollen selection has been described in this species.

  3. Nutrition metabolism plays an important role in the alternate bearing of the olive tree (Olea europaea L.).

    PubMed

    Turktas, Mine; Inal, Behcet; Okay, Sezer; Erkilic, Emine Gulden; Dundar, Ekrem; Hernandez, Pilar; Dorado, Gabriel; Unver, Turgay

    2013-01-01

    The olive tree (Olea europaea L.) is widely known for its strong tendency for alternate bearing, which severely affects the fruit yield from year to year. Microarray based gene expression analysis using RNA from olive samples (on-off years leaves and ripe-unripe fruits) are particularly useful to understand the molecular mechanisms influencing the periodicity in the olive tree. Thus, we carried out genome wide transcriptome analyses involving different organs and temporal stages of the olive tree using the NimbleGen Array containing 136,628 oligonucleotide probe sets. Cluster analyses of the genes showed that cDNAs originated from different organs could be sorted into separate groups. The nutritional control had a particularly remarkable impact on the alternate bearing of olive, as shown by the differential expression of transcripts under different temporal phases and organs. Additionally, hormonal control and flowering processes also played important roles in this phenomenon. Our analyses provide further insights into the transcript changes between "on year" and "off year" leaves along with the changes from unrpipe to ripe fruits, which shed light on the molecular mechanisms underlying the olive tree alternate bearing. These findings have important implications for the breeding and agriculture of the olive tree and other crops showing periodicity. To our knowledge, this is the first study reporting the development and use of an olive array to document the gene expression profiling associated with the alternate bearing in olive tree.

  4. Isolation and partial characterization of a highly divergent lineage of hantavirus from the European mole (Talpa europaea).

    PubMed

    Gu, Se Hun; Kumar, Mukesh; Sikorska, Beata; Hejduk, Janusz; Markowski, Janusz; Markowski, Marcin; Liberski, Paweł P; Yanagihara, Richard

    2016-02-19

    Genetically distinct hantaviruses have been identified in five species of fossorial moles (order Eulipotyphla, family Talpidae) from Eurasia and North America. Here, we report the isolation and partial characterization of a highly divergent hantavirus, named Nova virus (NVAV), from lung tissue of a European mole (Talpa europaea), captured in central Poland in August 2013. Typical hantavirus-like particles, measuring 80-120 nm in diameter, were found in NVAV-infected Vero E6 cells by transmission electron microscopy. Whole-genome sequences of the isolate, designated NVAV strain Te34, were identical to that amplified from the original lung tissue, and phylogenetic analysis of the full-length L, M and S segments, using maximum-likelihood and Bayesian methods, showed that NVAV was most closely related to hantaviruses harbored by insectivorous bats, consistent with an ancient evolutionary origin. Infant Swiss Webster mice, inoculated with NVAV by the intraperitoneal route, developed weight loss and hyperactivity, beginning at 16 days, followed by hind-limb paralysis and death. High NVAV RNA copies were detected in lung, liver, kidney, spleen and brain by quantitative real-time RT-PCR. Neuropathological examination showed astrocytic and microglial activation and neuronal loss. The first mole-borne hantavirus isolate will facilitate long-overdue studies on its infectivity and pathogenic potential in humans.

  5. Isolation and partial characterization of a highly divergent lineage of hantavirus from the European mole (Talpa europaea)

    PubMed Central

    Gu, Se Hun; Kumar, Mukesh; Sikorska, Beata; Hejduk, Janusz; Markowski, Janusz; Markowski, Marcin; Liberski, Paweł P.; Yanagihara, Richard

    2016-01-01

    Genetically distinct hantaviruses have been identified in five species of fossorial moles (order Eulipotyphla, family Talpidae) from Eurasia and North America. Here, we report the isolation and partial characterization of a highly divergent hantavirus, named Nova virus (NVAV), from lung tissue of a European mole (Talpa europaea), captured in central Poland in August 2013. Typical hantavirus-like particles, measuring 80–120 nm in diameter, were found in NVAV-infected Vero E6 cells by transmission electron microscopy. Whole-genome sequences of the isolate, designated NVAV strain Te34, were identical to that amplified from the original lung tissue, and phylogenetic analysis of the full-length L, M and S segments, using maximum-likelihood and Bayesian methods, showed that NVAV was most closely related to hantaviruses harbored by insectivorous bats, consistent with an ancient evolutionary origin. Infant Swiss Webster mice, inoculated with NVAV by the intraperitoneal route, developed weight loss and hyperactivity, beginning at 16 days, followed by hind-limb paralysis and death. High NVAV RNA copies were detected in lung, liver, kidney, spleen and brain by quantitative real-time RT-PCR. Neuropathological examination showed astrocytic and microglial activation and neuronal loss. The first mole-borne hantavirus isolate will facilitate long-overdue studies on its infectivity and pathogenic potential in humans. PMID:26892544

  6. Nutrition Metabolism Plays an Important Role in the Alternate Bearing of the Olive Tree (Olea europaea L.)

    PubMed Central

    Turktas, Mine; Inal, Behcet; Okay, Sezer; Erkilic, Emine Gulden; Dundar, Ekrem; Hernandez, Pilar; Dorado, Gabriel; Unver, Turgay

    2013-01-01

    The olive tree (Olea europaea L.) is widely known for its strong tendency for alternate bearing, which severely affects the fruit yield from year to year. Microarray based gene expression analysis using RNA from olive samples (on-off years leaves and ripe-unripe fruits) are particularly useful to understand the molecular mechanisms influencing the periodicity in the olive tree. Thus, we carried out genome wide transcriptome analyses involving different organs and temporal stages of the olive tree using the NimbleGen Array containing 136,628 oligonucleotide probe sets. Cluster analyses of the genes showed that cDNAs originated from different organs could be sorted into separate groups. The nutritional control had a particularly remarkable impact on the alternate bearing of olive, as shown by the differential expression of transcripts under different temporal phases and organs. Additionally, hormonal control and flowering processes also played important roles in this phenomenon. Our analyses provide further insights into the transcript changes between ”on year” and “off year” leaves along with the changes from unrpipe to ripe fruits, which shed light on the molecular mechanisms underlying the olive tree alternate bearing. These findings have important implications for the breeding and agriculture of the olive tree and other crops showing periodicity. To our knowledge, this is the first study reporting the development and use of an olive array to document the gene expression profiling associated with the alternate bearing in olive tree. PMID:23555820

  7. Aromadendrine, a new component of the flavonoid pattern of Olea europaea L. and its anti-inflammatory activity.

    PubMed

    Venditti, Alessandro; Serrilli, Anna Maria; Rizza, Luisa; Frasca, Giuseppina; Cardile, Venera; Bonina, Francesco Paolo; Bianco, Armandodoriano

    2013-03-01

    Leaves of Olea europaea, cultivar Nocellara del Belice, were examined with respect to the medium-polar fraction, obtained by an ethyl acetate extraction of the whole extract. In the medium polar fraction, we isolated the two hydroxy-phenyl-ethyl alcohols (hydroxyl-tyrosol and tyrosol) that are the main component of olives. In addition, we isolated a flavonoidic compound, aromadendrine, a dihydroflavonol yet known but quite rare in nature. It is the first time that aromadendrine is isolated in O. europaea and we studied the aromadendrine biological activity. In particular, the ability of aromadendrine to reduce the inflammation induced in normal keratinocytes using an in vitro cell model was evaluated. The results of the present research indicate aromadendrine as a novel component in O. europaea with effective activity against skin inflammation.

  8. Extraction and Characterization of Lipids from Salicornia virginica and Salicornia europaea

    NASA Technical Reports Server (NTRS)

    Kulis,Michael J.; Hepp, Aloysius F.; Pham, Phong X.; Ribita, Daniela; Bomani, Bilal M. M.; Duraj, Stan A.

    2010-01-01

    The lipid content from Salicornia virginica and Salicornia europaea is investigated. The plants are leafless halophytes with seeds contained in terminal nodes. The lipids, in the form of cell membranes and oil bodies that come directly from the node cells, are observed using fluorescence microscopy. Two extraction methods as well as the results of extracting from the seeds and from the entire nodes are described. Characterization of the fatty acid components of the lipids using Gas Chromatography in tandem with Mass Spectroscopy is also described. Comparisons are made between the two methods and between the two plant materials as lipid sources.

  9. Biosynthesis and biotransformations of phenol-conjugated oleosidic secoiridoids from Olea europaea L.

    PubMed

    Obied, Hassan K; Prenzler, Paul D; Ryan, Danielle; Servili, Maurizio; Taticchi, Agnese; Esposto, Sonia; Robards, Kevin

    2008-12-01

    The genus Olea contains the economically important European olive tree (Olea europaea L.). This species is also of chemotaxonomic interest because of the presence of various phenol-conjugated oleosidic secoiridoids or oleosides. The chemistry of these phenolic oleosides is diverse and complicated, and it is only in recent years that attention has been given to their biosynthesis and the biotransformations during the processing and storage of olive products. Many questions regarding these processes remain unanswered, and yet these have significant impact on the quality and value of olive products such as olive oil.

  10. Effect of NaCl concentration on productivity and mineral composition of Salicornia europaea as a potential crop for utilization NaCl in LSS

    NASA Astrophysics Data System (ADS)

    Ushakova, S. A.; Kovaleva, N. P.; Gribovskaya, I. V.; Dolgushev, V. A.; Tikhomirova, N. A.

    The accumulation of solid and liquid wastes in manmade ecosystems presents a problem that has not been efficiently solved yet. Urine, containing NaCl, are part of these products. This is an obstacle to the creation of biological systems with a largely closed material cycling, because the amount of solid and liquid wastes in them must be reduced to a minimum. A possible solution to the problem is to select plant species capable of utilizing sufficiently high concentrations of NaCl, edible for humans, and featuring high productivity. Until recently, the life support systems have included the higher plants that were either sensitive to salinization (wheat, many of the legumes, carrot, potato, maize) or relatively salt-resistant (barley, sugar beet, spinach). Salicomia europaea, whose above-ground part is fully edible for humans, is one of the most promising candidates to be included in life support systems. It is reported in the literature that this plant is capable of accumulating up to 50% NaCl (dry basis). Besides, excessive accumulation of sodium ions should bring forth a decrease in the uptake of potassium ions and other biogenic elements. The aim of this work is to study the feasibility of using S. europaea plants in growth chambers to involve NaCl into material cycling. Plants were grown in vegetation chambers at the irradiance of 100 or 150 W/m 2 PAR (photosynthetically active radiation) and the air temperature 24 °C, by two methods. The first method was to grow the plants on substrate - peat. The peat was supplemented with either 3% NaCl (Variant 1) or 6% NaCl (Variant 2) of the oven-dry mass of the peat. The second method was to grow the plants in water culture, using the solution with a full complement of nutrients, which contained 0.0005% of NaCl, 1% or 2%. The study showed that the addition of NaCl to the substrate or to the solution resulted in the formation of more succulent plants, which considerably increased their biomass. The amount of NaCl uptake

  11. Final Intrinsic Remediation Engineering Evaluation/Cost Analysis for the FT-002 Site, Plattsburg Air Force Base, New York

    DTIC Science & Technology

    1995-04-01

    of trichloroethylene by the ammonia-oxidizing bacterium Nitrosomonas europaea : Biochem. Biophys. Res. Commun., vol. 159, p. 640-643. I Atlas, R.M...aliphatic compounds by the ammonia-oxidizing bacterium Nitrosomonas europaea : Appl. Environ. Microbiol., vol. 56, no. 4, p. 1169-1171. * Verschueren, K

  12. Phenolic Compounds from Olea europaea L. Possess Antioxidant Activity and Inhibit Carbohydrate Metabolizing Enzymes In Vitro

    PubMed Central

    Dekdouk, Nadia; Malafronte, Nicola; Russo, Daniela; Faraone, Immacolata; De Tommasi, Nunziatina; Ameddah, Souad; Severino, Lorella; Milella, Luigi

    2015-01-01

    Phenolic composition and biological activities of fruit extracts from Italian and Algerian Olea europaea L. cultivars were studied. Total phenolic and tannin contents were quantified in the extracts. Moreover 14 different phenolic compounds were identified, and their profiles showed remarkable quantitative differences among analysed extracts. Moreover antioxidant and enzymatic inhibition activities were studied. Three complementary assays were used to measure their antioxidant activities and consequently Relative Antioxidant Capacity Index (RACI) was used to compare and easily describe obtained results. Results showed that Chemlal, between Algerian cultivars, and Coratina, among Italian ones, had the highest RACI values. On the other hand all extracts and the most abundant phenolics were tested for their efficiency to inhibit α-amylase and α-glucosidase enzymes. Leccino, among all analysed cultivars, and luteolin, among identified phenolic compounds, were found to be the best inhibitors of α-amylase and α-glucosidase enzymes. Results demonstrated that Olea europaea fruit extracts can represent an important natural source with high antioxidant potential and significant α-amylase and α-glucosidase inhibitory effects. PMID:26557862

  13. Genetic Diversity Among Historical Olive (Olea europaea L.) Genotypes from Southern Anatolia Based on SSR Markers.

    PubMed

    Sakar, Ebru; Unver, Hulya; Ercisli, Sezai

    2016-12-01

    Olive (Olea europaea) is an ancient and important crop in both olive oil production and table use. It is important to identify the genetic diversity of olive genetic resources for cultivar development and evaluation of olive germplasm. In the study, 14 microsatellite markers (UDO4, UDO8, UDO9, UDO11, UDO12, UDO22, UDO24, UDO26, UDO28, DCA9, DCA11, DCA13, DCA15, and DCA18) were used to assess the genetic variation on 76 olive (Olea europaea L.) genotypes from Mardin province together with 6 well-known Turkish and 4 well-known foreign reference cultivars. All microsatellite markers showed polymorphism and the number of alleles varied between 9 and 22, with an average of 14.57. The most informative loci were DCA 11 (22 alleles) and DCA 9 (21 alleles). Dendrogram based on genetic distances was constructed for the 86 olive genotypes/cultivars, which revealed the existence of different clusters. The high genetic similarity was evident between Bakırkire2 and Zinnar5 (0.74) genotypes, while the most genetically divergent genotypes were Gürmeşe5 and Yedikardeşler2 (0.19). It was concluded that there was abundant SSR polymorphism in olive germplasm in southern Anatolia in Turkey and could be important for future breeding activities.

  14. Bioactive derivatives from oleuropein by a biotransformation on Olea europaea leaf extracts.

    PubMed

    Briante, Raffaella; La Cara, Francesco; Febbraio, Ferdinando; Patumi, Maurizio; Nucci, Roberto

    2002-02-14

    A very simple method is proposed to produce, using non-homogeneous hyperthermophilic beta-glycosidase immobilised on chitosan, 3,4-dihydroxy-phenylethanol (hydroxytyrosol), a commercially unavailable compound with well known biological properties which justify a potential commercial application. Leaf extracts from Olea europaea with high oleuropein content are selected as substrate for biotransformation. Under the biotransformation conditions, high amounts of hydroxytyrosol are collected within a short space of time after being preliminarily purified by a non-treated chitosan column. This is possible due to the capacity of amino groups on the chitosan to bind aldehydic groups of molecules present at the end of the reaction. We have produced a natural and non-toxic product from vegetal source, as opposed to the molecule obtainable through chemical synthesis, as a candidate to test in vivo its biological properties. The proposed process may prove useful for a further application for recycling Olea europaea leaves. The radical-scavenging properties of the bioreactor eluates and their capacity to inhibit fatty acid peroxidation rates are characterized in order to make them candidates as substitutes for synthetic antioxidants commonly used to increase the shelf-life of food products as well as for their possible protective effect in human cells.

  15. Polyphenol deposition in leaf hairs of Olea europaea (Oleaceae) and Quercus ilex (Fagaceae).

    PubMed

    Karabourniotis, G; Kofidis, G; Fasseas, C; Liakoura, V; Drossopoulos, I

    1998-07-01

    The subcellular localization (cytoplasm, vacuoles, cell walls) of polyphenol compounds during the development of the multicellular nonglandular leaf hairs of Olea europaea (scales) and Quercus ilex (stellates), was investigated. Hairs of all developmental stages were treated with specific inducers of polyphenol fluorescence, and the bright yellow-green fluorescence of individual hairs was monitored with epifluorescence microscopy. During the early ontogenetic stages, bright fluorescence was emitted from the cytoplasm of the cells composing the multicellular shield of the scales of O. europaea. Transmission electron micrographs of the same stages showed that these cells possessed poor vacuolation and thin cell walls. The nucleus of these cells may be protected against ultraviolet-B radiation damage. The progressive vacuolation that occurred during maturation was followed by a shifting of the bright green-yellow fluorescence from the perinuclear region and the cytoplasm to the cell walls. The same trends were observed during the development of the nonglandular stellate hairs of Quercus ilex, in which maturation was also accompanied by a considerable secondary thickening of the cell walls. Despite the differences in morphology, high concentrations of polyphenol compounds are initially located mainly in the cytoplasm of the developing nonglandular hairs, and their deposition on the cell walls takes place during the secondary cell wall thickening. These structural changes during the development of the leaf hairs make them a very effective barrier against abiotic (uv-B radiation) and probably biotic (pathogenic) stresses.

  16. Essential oil composition of stems and fruits of Caralluma europaea N.E.Br. (Apocynaceae).

    PubMed

    Zito, Pietro; Sajeva, Maurizio; Bruno, Maurizio; Maggio, Antonella; Rosselli, Sergio; Formisano, Carmen; Senatore, Felice

    2010-01-27

    The essential oil of the stems and fruits of Caralluma europaea (Guss.) N.E.Br. (Apocynaceae) from Lampedusa Island has been obtained by hydrodistillation and its composition analyzed. The analyses allowed the identification and quantification of 74 volatile compounds, of which 16 were aromatic and 58 non-aromatic. Stems and fruits contained 1.4% and 2.7% of aromatic compounds respectively, while non-aromatic were 88.3% and 88.8%. Non-aromatic hydrocarbons were the most abundant compounds in both organs, followed by fatty acids. Data showed differences in the profiles between stems and fruits which shared only eighteen compounds; stems accounted for 38 compounds while fruits for 53. Fruits showed a higher diversity especially in aromatic compounds with twelve versus four in stems. Among the volatiles identified in stems and fruits of C. europaea 26 are present in other taxa of Apocynaceae, 52 are semiochemicals for many insects, and 21 have antimicrobial activity. The possible ecological role of the volatiles found is briefly discussed.

  17. The Response of Nitrifying Bacteria to Treatments of N-Serve and Roundup in Continuous-Flow Soil Columns

    DTIC Science & Technology

    1988-07-15

    Nitrosomonas europaea Soil Nitrosospira briensis Soil Nitrosococcus nitrosus Soil Nitrosococcus oceanus Atlantic and Pacific Oceans Nitrosolobus...Knowles (1987) found that nitrification was inhibited in a Humisol under conditions suitable for the active growth of methanotr!ophs, These investigators...alfalfa root extracts inhibited Nitrosomonas yet had no effect or. the growth of Nitrobacter. Corn root extracts also inhibited Nitrosomonas but

  18. Biological Degradation of Hydrazine.

    DTIC Science & Technology

    1979-10-01

    inhibition of ammonia oxidation at 32 mg/Z. 3 Yoshida and Alexander used neat hydrazine as a selective inhibitor in their studies with Nitrosomonas europaea ...Formation by Nitrosomonas europaea ", Canadian Journal of Microbiology, Vol 10, 1964. 4. Verstraete, W. and M. Alexander, "Heterotrophic Nitrification by...Nitrosgmonas sp. in activated sludge was in general agreement with Meyerhof- who studied pure cultures of Nitrosomonas sp. and found 20-percent

  19. Hot water dipping of olives (Olea europaea) for virgin oil debittering.

    PubMed

    García, José M; Yousfi, Khaled; Oliva, Jesús; García-Diaz, M Teresa; Pérez-Camino, M Carmen

    2005-10-19

    Olives (Olea europaea L.) of the Manzanilla, Picual, and Verdial varieties harvested at the green mature stage of ripening were dipped in hot water at a range of temperatures between 60 and 72 degrees C for 3 min. Immediately after treatment, oils were physically extracted from the olives. Olive heating promotes a reduction of oil bitterness in direct relationship to the temperature used. Fruit heating at > or =60 degrees C for 3 min did not cause significant changes in acidity, UV absorption, peroxide index, and panel test score of the oils obtained but decreased its oxidative stability. Oils extracted from heated fruit showed higher concentrations of chlorophylls and carotenes and lower total phenol content.

  20. Reduction of oil bitterness by heating of olive (Olea europaea) fruits.

    PubMed

    García, J M; Yousfi, K; Mateos, R; Olmo, M; Cert, A

    2001-09-01

    Olives (Olea europaea) of the Manzanilla and Verdial varieties, harvested at the green mature stage of ripening, were heated at 30, 40, 45, and 50 degrees C during 24 h and at 40 degrees C during 24, 48, and 72 h, respectively. Just after treatments, oils were physically extracted from the olives. Olive heating promotes a reduction of oil bitterness in direct relationship to the time and temperature used. Fruit heating at < or =40 degrees C during 24 h did not produce significant changes of acidity, UV absorption, peroxide index, panel test score, or oxidative stability of the obtained oils. Both longer treatments at 40 degrees C and heating at >40 degrees C yielded oils with less oxidative stability. Oils obtained from olives heated at > or =40 degrees C showed higher concentrations of chlorophylls and carotenes. For each olive variety, a good correlation between oil bitterness and content of hydroxytyrosol secoiridoid derivatives was found.

  1. H(+)-pyrophosphatase from Salicornia europaea enhances tolerance to low phosphate under salinity in Arabidopsis.

    PubMed

    Lv, Sulian; Jiang, Ping; Wang, Duoliya; Li, Yinxin

    2016-01-01

    Increasing soil salinity threatens crop productivity worldwide. High soil salinity is usually accompanied by the low availability of many mineral nutrients. Here, we investigated the potential role that the H(+)- PPase could play in optimizing P use efficiency under salinity in plants. Transgenic Arabidopsis plants overexpressing either SeVP1 or SeVP2 from Salicornia europaea outperformed the wild-types under low phosphate (Pi) as well as low Pi plus salt conditions. Our results suggested that H(+)-PPase could increase external Pi acquisition through promoting root development and upregulating phosphate transporters, thus to protect plants from Pi limiting stress. This study provides a potential strategy for improving crop yields challenged by the co-occurrence of abiotic stresses.

  2. Antigenicity of the pollen proteins of various cultivars of Olea europaea.

    PubMed

    Waisel, Y; Geller-Bernstein, C; Keynan, N; Arad, G

    1996-11-01

    The incidence of positive skin test responses among atopic subjects with suspected respiratory allergy was investigated with commercial and autochthonous pollen extracts of various cultivars of Olea europaea. Pollen was collected from olive trees of well-defined cultivars, extracted, and separated by SDS-PAGE. Immunoblots were used to identify the various IgE-binding proteins of the pollen extracts of the various cultivars. The results revealed six predominant IgE-binding bands, some of which appear in all the cultivars examined. The 18-20-kDa band (Ole e 1) appeared in only eight of the cultivars, but not in the nine others. The presence of specific IgE-binding bands in the various pollen extracts and their correlation with the incidence of positive skin tests are discussed.

  3. Genetic Diversity of Talpa Europaea and Nova Hanta Virus (NVAV) in France

    PubMed Central

    Hugot, Jean-Pierre; Gu, Se Hun; Feliu, Carlos; Ventur, Jacint; Ribas, Alexis; Dormion, Jerôme; Yanagihara, Richard; Nicolas, Violaine

    2014-01-01

    Summary Nova hantavirus (NVAV) was first identified in a single European mole (Talpa europaea), captured in Hungary. Analysis of lung tissues from 94 moles captured in France revealed NVAV in 50%. Based on the genetic diversity of the cytochrome b mtDNA, moles collected in Poitiers and Bordeaux were more closely related to the Iberian mole (T. occidentalis), a species previously assumed to be restricted to the Iberian Peninsula. Several hypotheses are discussed to explain these observations: 1) presence of hitherto unnoticed T. occidentalis in southwestern France; 2) existence of an ancient mitochondrial introgression phenomenon between the two Talpa species, producing a particular phenotype in some hybrids; 3) existence of a hybrid zone between the two species; and 4) existence of a new Talpa species. NVAV was not detected in the southwestern moles, which begs the question of the potential presence of a particular Hantavirus sp. in this population and/or in the Iberian moles. PMID:25530620

  4. Observation of eight ancient olive trees (Olea europaea L.) growing in the Garden of Gethsemane.

    PubMed

    Petruccelli, Raffaella; Giordano, Cristiana; Salvatici, Maria Cristina; Capozzoli, Laura; Ciaccheri, Leonardo; Pazzini, Massimo; Lain, Orietta; Testolin, Raffaele; Cimato, Antonio

    2014-05-01

    For thousands of years, olive trees (Olea europaea L.) have been a significant presence and a symbol in the Garden of Gethsemane, a place located at the foot of the Mount of Olives, Jerusalem, remembered for the agony of Jesus Christ before his arrest. This investigation comprises the first morphological and genetic characterization of eight olive trees in the Garden of Gethsemane. Pomological traits, morphometric, and ultrastructural observations as well as SSR (Simple Sequence Repeat) analysis were performed to identify the olive trees. Statistical analyses were conducted to evaluate their morphological variability. The study revealed a low morphological variability and minimal dissimilarity among the olive trees. According to molecular analysis, these trees showed the same allelic profile at all microsatellite loci analyzed. Combining the results of the different analyses carried out in the frame of the present work, we could conclude that the eight olive trees of the Gethsemane Garden have been propagated from a single genotype.

  5. The antioxidant and anti-proliferative activity of the Lebanese Olea europaea extract.

    PubMed

    Fares, Rida; Bazzi, Samer; Baydoun, Serine E; Abdel-Massih, Roula M

    2011-03-01

    It is becoming increasingly evident that certain phytochemicals possess cancer chemopreventive properties. In this study, the anti-proliferative activity of plant extracts from olive (Olea europaea L.) leaves was tested on human leukemic cell line (Jurkat). Cytotoxicity of various concentrations of plant extracts was examined and the IC(50) was determined. Olive leaf extracts showed concentration-dependent anti-proliferative effect as determined by the WST-1 proliferation kit and [(3)H]-thymidine incorporation method. To study whether cell death was due to apoptosis, cells were stained with Annexin V-FITC and PI and the expression of important regulatory proteins (Bcl-2, Bax, and p53) involved in apoptosis were examined by Western blot. The antioxidant activity of olive leaves (SC(50) = 0.1 mg dry weight) was studied using the DPPH scavenging method. Present findings suggest that olive leaves extracts exhibit anti-proliferative effect on leukemic cells by inducing apoptosis.

  6. Olive tree (Olea europaea) leaves: potential beneficial effects on human health.

    PubMed

    El, Sedef N; Karakaya, Sibel

    2009-11-01

    Olive tree (Olea europaea L.) leaves have been widely used in traditional remedies in European and Mediterranean countries such as Greece, Spain, Italy, France, Turkey, Israel, Morocco, and Tunisia. They have been used in the human diet as an extract, an herbal tea, and a powder, and they contain many potentially bioactive compounds that may have antioxidant, antihypertensive, antiatherogenic, anti-inflammatory, hypoglycemic, and hypocholesterolemic properties. One of these potentially bioactive compounds is the secoiridoid oleuropein, which can constitute up to 6-9% of dry matter in the leaves. Other bioactive components found in olive leaves include related secoiridoids, flavonoids, and triterpenes. The evidence supporting the potentially beneficial effects of olive leaves on human health are presented in this brief review.

  7. A Comprehensive Toxicological Safety Assessment of an Extract of Olea Europaea L. Leaves (Bonolive™).

    PubMed

    Clewell, Amy E; Béres, Erzsébet; Vértesi, Adél; Glávits, Róbert; Hirka, Gábor; Endres, John R; Murbach, Timothy S; Szakonyiné, Ilona Pasics

    2016-01-01

    A battery of toxicological studies was conducted to investigate the genotoxicity and repeated-dose oral toxicity of Bonolive™, a proprietary water-soluble extract of the leaves of the olive tree (Olea europaea L.), in accordance with internationally accepted protocols. There was no evidence of mutagenicity in a bacterial reverse mutation test and in an vitro mammalian chromosomal aberration test nor was any genotoxic activity observed in an in vivo mouse micronucleus test at concentrations up to the limit dose of 2000 mg/kg bw/d. Bonolive™ did not cause mortality or toxic effects in Crl:(WI)BR Wistar rats in a 90-day repeated-dose oral toxicity study at doses of 360, 600, and 1000 mg/kg bw/d. The no observed adverse effect level in the 90-day study was 1000 mg/kg bw/d for both male and female rats, the highest dose tested.

  8. Factors influencing phenolic compounds in table olives (Olea europaea).

    PubMed

    Charoenprasert, Suthawan; Mitchell, Alyson

    2012-07-25

    The Mediterranean diet appears to be associated with a reduced risk of several chronic diseases including cancer and cardiovascular and Alzheimer's diseases. Olive products (mainly olive oil and table olives) are important components of the Mediterranean diet. Olives contain a range of phenolic compounds; these natural antioxidants may contribute to the prevention of these chronic conditions. Consequently, the consumption of table olives and olive oil continues to increase worldwide by health-conscious consumers. There are numerous factors that can affect the phenolics in table olives including the cultivar, degree of ripening, and, importantly, the methods used for curing and processing table olives. The predominant phenolic compound found in fresh olive is the bitter secoiridoid oleuropein. Table olive processing decreases levels of oleuropein with concomitant increases in the hydrolysis products hydroxytyrosol and tyrosol. Many of the health benefits reported for olives are thought to be associated with the levels of hydroxytyrosol. Herein the pre- and post-harvest factors influencing the phenolics in olives, debittering methods, and health benefits of phenolics in table olives are reviewed.

  9. Dried leaf extract of Olea europaea ameliorates islet-directed autoimmunity in mice.

    PubMed

    Cvjetićanin, Tamara; Miljković, Djordje; Stojanović, Ivana; Dekanski, Dragana; Stosić-Grujicić, Stanislava

    2010-05-01

    The health-promoting effects of various constituents of the olive tree (Olea europaea) are mainly associated with hypoglycaemic and insulin-sensitising activities and have been widely demonstrated in the metabolic syndrome and type 2 diabetes. However, their biological activity in autoimmune type 1 diabetes (T1D) is poorly characterised. Therefore, the influence of O. europaea-derived components present in dry olive leaf extract (DOLE) was examined in two established preclinical models of human T1D, which differ in some aspects of diabetogenesis: multiple low-dose streptozotocin-induced diabetes in susceptible C57BL/6 and CBA/H mouse strains; cyclophosphamide-accelerated diabetes in non-obese diabetic mice. In both T1D models, in vivo administration of DOLE significantly reduced clinical signs of diabetes (hyperglycaemia and body weight loss) and led to complete suppression of histopathological changes in pancreatic islets. In line with these, insulin expression and release were restored in DOLE-treated mice. Interestingly, inducible NO synthase expression and NO production were significantly elevated in peripheral tissues but were down-regulated within the local environment of the endocrine pancreas. This interference was reflected in NO-mediated suppression of T lymphocyte proliferation and lower production of the proinflammatory cytokines interferon-gamma, IL-17 and TNF-alpha in the spleen, with subsequent blockade of beta-cell destruction. The results suggest that DOLE interferes with development of autoimmune diabetes by down-regulating production of proinflammatory and cytotoxic mediators. Therefore, the potential use of a DOLE-enriched diet for prophylaxis/treatment of human T1D, and possibly other autoimmune diseases, is worthy of further investigation.

  10. Growth and nitrogen uptake by Salicornia europaea and Aster tripolium in nutrient conditions typical of aquaculture wastewater.

    PubMed

    Quintã, R; Santos, R; Thomas, D N; Le Vay, L

    2015-02-01

    The increasing need for environmentally sound aquaculture development can, in part, be addressed by using halophytic plants in integrated multitrophic aquaculture systems (IMTA) to remove waste dissolved nitrogen (N). However, knowledge of plant ability to take up nitrogen is of foremost importance to predict plants performance in such systems. Two species, Salicornia europaea and Aster tripolium, have been identified as potential candidates for IMTA due to their salt tolerance, potential N removal capabilities and their high commercial value as an additional crop. This study investigated the growth and N uptake rates of these two species under different N supply (NH4(+), NO3(-), NH4NO3). S. europaea plants produced a lower biomass when grown in NH4(+) compared to NO3(-) or NH4NO3, while A. tripolium biomass was not affected by the form in which N was supplied. N uptake in plants incubated at different concentrations of (15)N enriched solution (up to 2 mmol l(-1)) fitted the Michaelis-Menten model. While S. europaea NH4-N maximum uptake did not differ between starved and non-starved plants, A. tripolium NH4-N uptake was higher in starved plants when supplied alone. When NO3(-) was supplied alone, NO3-N maximum uptake was lower, for both species, when the plants were not starved. Comparison of starved and non-starved plants N uptake demonstrates the need for cautious interpretation of N uptake rates across different conditions. According to the observed results, both S. europaea and A. tripolium are capable of significantly high biomass production and N removal making them potential species for inclusion in efficient IMTA.

  11. Colonization of olive trees (Olea europaea L.) with the arbuscular mycorrhizal fungus Glomus sp. modified the glycolipids biosynthesis and resulted in accumulation of unsaturated fatty acids.

    PubMed

    Mechri, Beligh; Attia, Faouzi; Tekaya, Meriem; Cheheb, Hechmi; Hammami, Mohamed

    2014-09-01

    The influence of arbuscular mycorrhizal (AM) fungi colonization on photosynthesis, mineral nutrition, the amount of phospholipids and glycolipids in the leaves of olive (Olea europaea L.) trees was investigated. After six months of growth, the rate of photosynthesis, carboxylation efficiency, transpiration and stomatal conductance in mycorrhizal (M) plants was significantly higher than that of non-mycorrhizal (NM) plants. The inoculation treatment increased the foliar P and Mg but not N. The amount of glycolipids in the leaves of M plants was significantly higher than that of NM plants. However, the amount of phospholipids in the leaves of M plants was not significantly different to that in the leaves of NM plants. Also, we observed a significant increase in the level of α-linolenic acid (C18:3ω3) in glycolipids of M plants. This work supports the view that increased glycolipids level in the leaves of M plants could be involved, at least in part, in the beneficial effects of mycorrhizal colonization on photosynthesis performance of olive trees. To our knowledge, this is the first report on the effect of AM fungi on the amount of glycolipids in the leaves of mycorrhizal plants.

  12. Olive (Olea europaea) leaf extract effective in patients with stage-1 hypertension: comparison with Captopril.

    PubMed

    Susalit, Endang; Agus, Nafrialdi; Effendi, Imam; Tjandrawinata, Raymond R; Nofiarny, Dwi; Perrinjaquet-Moccetti, Tania; Verbruggen, Marian

    2011-02-15

    A double-blind, randomized, parallel and active-controlled clinical study was conducted to evaluate the anti-hypertensive effect as well as the tolerability of Olive leaf extract in comparison with Captopril in patients with stage-1 hypertension. Additionally, this study also investigated the hypolipidemic effects of Olive leaf extract in such patients. It consisted of a run-in period of 4 weeks continued subsequently by an 8-week treatment period. Olive (Olea europaea L.) leaf extract (EFLA(®)943) was given orally at the dose of 500 mg twice daily in a flat-dose manner throughout the 8 weeks. Captopril was given at the dosage regimen of 12.5 mg twice daily at start. After 2 weeks, if necessary, the dose of Captopril would be titrated to 25 mg twice daily, based on subject's response to treatment. The primary efficacy endpoint was reduction in systolic blood pressure (SBP) from baseline to week-8 of treatment. The secondary efficacy endpoints were SBP as well as diastolic blood pressure (DBP) changes at every time-point evaluation and lipid profile improvement. Evaluation of BP was performed every week for 8 weeks of treatment; while of lipid profile at a 4-week interval. Mean SBP at baseline was 149.3±5.58 mmHg in Olive group and 148.4±5.56 mmHg in Captopril group; and mean DBPs were 93.9±4.51 and 93.8±4.88 mmHg, respectively. After 8 weeks of treatment, both groups experienced a significant reduction of SBP as well as DBP from baseline; while such reductions were not significantly different between groups. Means of SBP reduction from baseline to the end of study were -11.5±8.5 and -13.7±7.6 mmHg in Olive and Captopril groups, respectively; and those of DBP were -4.8±5.5 and -6.4±5.2 mmHg, respectively. A significant reduction of triglyceride level was observed in Olive group, but not in Captopril group. In conclusion, Olive (Olea europaea) leaf extract, at the dosage regimen of 500 mg twice daily, was similarly effective in lowering systolic and

  13. Assessment of Olea europaea L. fruit extracts: Phytochemical characterization and anticancer pathway investigation.

    PubMed

    Maalej, Amina; Bouallagui, Zouhaier; Hadrich, Fatma; Isoda, Hiroko; Sayadi, Sami

    2017-03-27

    Olea europaea L. has been widely used as an advantageous rich source of bioactive compounds of high economic value leading to its use in pharmaceutical, cosmetic, and agriculture industries. Ethanolic extracts of olive fruits from three different cultivars (OFE) were studied for their phytochemical contents and were investigated for antioxidant activities and anticancer potential. Major polyphenols detected in these extracts were tyrosol, hydroxytyrosol, oleuropein, rutin, quercetin and glucoside forms of luteolin and apigenin. All these compounds have shown to significantly contribute to the antioxidant activity of OFE, which was evaluated by DPPH and ABTS assays. Proliferation of hepatic and colon cancer cells, HepG2 and Caco-2, were shown to be sensitive to OFE with IC50 less than 1.6mg/ml for all tested extracts. Moreover, flow cytometry analysis showed that OFE induced cell cycle arrest in the S-phase within both HepG2 and Caco-2 cells. This has triggered a cell death mechanism as shown by DNA fragmentation, expression of p53 and phosphorylation level of Akt and Erk proteins. Interestingly, these extracts could be further used as a potential source of natural compounds with both antioxidant and anticancer effects.

  14. Identification of ancient Olea europaea L. and Cornus mas L. seeds by DNA barcoding.

    PubMed

    Gismondi, Angelo; Rolfo, Mario Federico; Leonardi, Donatella; Rickards, Olga; Canini, Antonella

    2012-07-01

    The analysis of ancient DNA (aDNA) provides archaeologists and anthropologists with innovative, scientific and accurate data to study and understand the past. In this work, ancient seeds, found in the "Mora Cavorso" archaeological site (Latium, Central Italy), were analyzed to increase information about Italian Neolithic populations (plant use, agriculture, diet, trades, customs and ecology). We performed morphological and genetic techniques to identify fossil botanical species. In particular, this study also suggests and emphasizes the use of DNA barcode method for ancient plant sample analysis. Scanning electron microscope (SEM) observations showed seed compact structure and irregular surface but they did not permit a precise nor empirical classification: so, a molecular approach was necessary. DNA was extracted from ancient seeds and then it was used, as template, for PCR amplifications of standardized barcode genes. Although aDNA could be highly degraded by the time, successful PCR products were obtained, sequenced and compared to nucleotide sequence databases. Positive outcomes (supported by morphological comparison with modern seeds, geographical distribution and historical data) indicated that seeds could be identified as belonging to two plant species: Olea europaea L. and Cornus mas L.

  15. Temporal matching among diurnal photosynthetic patterns within the crown of the evergreen sclerophyll Olea europaea L.

    PubMed

    Granado-Yela, C; García-Verdugo, C; Carrillo, K; Rubio DE Casas, R; Kleczkowski, L A; Balaguer, L

    2011-05-01

    Trees are modular organisms that adjust their within-crown morphology and physiology in response to within-crown light gradients. However, whether within-plant variation represents a strategy for optimizing light absorption has not been formally tested. We investigated the arrangement of the photosynthetic surface throughout one day and its effects on the photosynthetic process, at the most exposed and most sheltered crown layers of a wild olive tree (Olea europaea L.). Similar measurements were made for cuttings taken from this individual and grown in a greenhouse at contrasted irradiance-levels (100 and 20% full sunlight). Diurnal variations in light interception, carbon fixation and carbohydrate accumulation in sun leaves were negatively correlated with those in shade leaves under field conditions when light intensity was not limiting. Despite genetic identity, these complementary patterns were not found in plants grown in the greenhouse. The temporal disparity among crown positions derived from specialization of the photosynthetic behaviour at different functional and spatial scales: architectural structure (crown level) and carbon budget (leaf level). Our results suggest that the profitability of producing a new module may not only respond to construction costs or light availability, but also rely on its spatio-temporal integration within the productive processes at the whole-crown level.

  16. Protective Effect of Salicornia europaea Extracts on High Salt Intake-Induced Vascular Dysfunction and Hypertension

    PubMed Central

    Panth, Nisha; Park, Sin-Hee; Kim, Hyun Jung; Kim, Deuk-Hoi; Oak, Min-Ho

    2016-01-01

    High salt intake causes and aggravates arterial hypertension and vascular dysfunction. We investigated the effect of Salicornia europaea extracts (SE) on vascular function and blood pressure. SE constituents were analyzed using high performance liquid chromatography, and SE’s effect on vascular function was evaluated in isolated porcine coronary arteries. SE’s vascular protective effect was also evaluated in vivo using normotensive and spontaneous hypertensive rats (SHRs). SE mainly contained sodium chloride (55.6%), 5-(hydroxymethyl)furfural, p-coumaric acid, and trans-ferulic acid. High sodium (160 mmol/L) induced vascular dysfunction; however, SE containing the same quantity of sodium did not cause vascular dysfunction. Among the compounds in SE, trans-ferulic acid accounts for the vascular protective effect. Normotensive rats fed a high-salt diet showed significantly increased systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP), which decreased significantly in the SE-treated groups. In SHRs, high edible salt intake significantly increased SBP, DBP, and MAP, but SE intake was associated with a significantly lower MAP. Thus, SE did not induce vascular dysfunction, and trans-ferulic acid might be at least partly responsible for the vasoprotective effect of SE. Taken together, SE could be used as an alternative to purified salt to prevent and ameliorate hypertension. PMID:27455235

  17. Epicuticular Wax in Developing Olives (Olea europaea) Is Highly Dependent upon Cultivar and Fruit Ripeness.

    PubMed

    Vichi, Stefania; Cortés-Francisco, Nuria; Caixach, Josep; Barrios, Gonçal; Mateu, Jordi; Ninot, Antonia; Romero, Agustí

    2016-08-03

    The epicuticular wax (EW) layer is located on the surface of most plant organs. It provides the cuticle with most of its properties and is the primary barrier against biotic and abiotic stress. Despite the importance of Olea europaea cultivation, few studies have characterized the EW covering leaves and olives, which could be involved in resistance to both infection and environmental conditions. In the present study, wide-ranging screening was carried out using direct-injection electrospray ionization coupled to high-resolution mass spectrometry to analyze EW in developing olives of nine varieties. The proportions of EW fractions [wax esters (WEs), diacylglycerols, triacylglycerols (TAGs), triterpenic acids, and aldehydes] strongly depended upon the olive cultivar and, in only a few cases, were influenced by the sampling date. The specific compositions of the major fractions, WEs and TAGs, were strictly related to the cultivar, while the degree of unsaturation and chain length of the WEs evolved throughout the 4 weeks prior to the olive turning color.

  18. Identification and Characterization of the Iridoid Synthase Involved in Oleuropein Biosynthesis in Olive (Olea europaea) Fruits*

    PubMed Central

    Kries, Hajo; Panara, Francesco; Baldoni, Luciana; O'Connor, Sarah E.; Osbourn, Anne

    2016-01-01

    The secoiridoids are the main class of specialized metabolites present in olive (Olea europaea L.) fruit. In particular, the secoiridoid oleuropein strongly influences olive oil quality because of its bitterness, which is a desirable trait. In addition, oleuropein possesses a wide range of pharmacological properties, including antioxidant, anti-inflammatory, and anti-cancer activities. In accordance, obtaining high oleuropein varieties is a main goal of molecular breeding programs. Here we use a transcriptomic approach to identify candidate genes belonging to the secoiridoid pathway in olive. From these candidates, we have functionally characterized the olive homologue of iridoid synthase (OeISY), an unusual terpene cyclase that couples an NAD (P)H-dependent 1,4-reduction step with a subsequent cyclization, and we provide evidence that OeISY likely generates the monoterpene scaffold of oleuropein in olive fruits. OeISY, the first pathway gene characterized for this type of secoiridoid, is a potential target for breeding programs in a high value secoiridoid-accumulating species. PMID:26709230

  19. Soil fluoride spiking effects on olive trees (Olea europaea L. cv. Chemlali).

    PubMed

    Zouari, M; Ben Ahmed, C; Fourati, R; Delmail, D; Ben Rouina, B; Labrousse, P; Ben Abdallah, F

    2014-10-01

    A pot experiment under open air conditions was carried out to investigate the uptake, accumulation and toxicity effects of fluoride in olive trees (Olea europaea L.) grown in a soil spiked with inorganic sodium fluoride (NaF). Six different levels (0, 20, 40, 60, 80 and 100mM NaF) of soil spiking were applied through NaF to irrigation water. At the end of the experiment, total fluoride content in soil was 20 and 1770mgFkg(-1) soil in control and 100mM NaF treatments, respectively. The comparative distribution of fluoride partitioning among the different olive tree parts showed that the roots accumulated the most fluoride and olive fruits were minimally affected by soil NaF spiking as they had the lowest fluoride content. In fact, total fluoride concentration varied between 12 and 1070µgFg(-1) in roots, between 9 and 570µgFg(-1) in shoots, between 12 and 290µgFg(-1) in leaves, and between 10 and 29µgFg(-1) in fruits, respectively for control and 100mM NaF treatments. Indeed, the fluoride accumulation pattern showed the following distribution: roots>shoots>leaves>fruits. On the other hand, fluoride toxicity symptoms such as leaf necrosis and leaf drop appeared only in highly spiked soils (60, 80 and 100mM NaF).

  20. Valuable nutrients and functional bioactives in different parts of olive (Olea europaea L.)-a review.

    PubMed

    Ghanbari, Rahele; Anwar, Farooq; Alkharfy, Khalid M; Gilani, Anwarul-Hassan; Saari, Nazamid

    2012-01-01

    The Olive tree (Olea europaea L.), a native of the Mediterranean basin and parts of Asia, is now widely cultivated in many other parts of the world for production of olive oil and table olives. Olive is a rich source of valuable nutrients and bioactives of medicinal and therapeutic interest. Olive fruit contains appreciable concentration, 1-3% of fresh pulp weight, of hydrophilic (phenolic acids, phenolic alchohols, flavonoids and secoiridoids) and lipophilic (cresols) phenolic compounds that are known to possess multiple biological activities such as antioxidant, anticarcinogenic, antiinflammatory, antimicrobial, antihypertensive, antidyslipidemic, cardiotonic, laxative, and antiplatelet. Other important compounds present in olive fruit are pectin, organic acids, and pigments. Virgin olive oil (VOO), extracted mechanically from the fruit, is also very popular for its nutritive and health-promoting potential, especially against cardiovascular disorders due to the presence of high levels of monounsaturates and other valuable minor components such as phenolics, phytosterols, tocopherols, carotenoids, chlorophyll and squalene. The cultivar, area of production, harvest time, and the processing techniques employed are some of the factors shown to influence the composition of olive fruit and olive oil. This review focuses comprehensively on the nutrients and high-value bioactives profile as well as medicinal and functional aspects of different parts of olives and its byproducts. Various factors affecting the composition of this food commodity of medicinal value are also discussed.

  1. Identification and Characterization of the Iridoid Synthase Involved in Oleuropein Biosynthesis in Olive (Olea europaea) Fruits.

    PubMed

    Alagna, Fiammetta; Geu-Flores, Fernando; Kries, Hajo; Panara, Francesco; Baldoni, Luciana; O'Connor, Sarah E; Osbourn, Anne

    2016-03-11

    The secoiridoids are the main class of specialized metabolites present in olive (Olea europaea L.) fruit. In particular, the secoiridoid oleuropein strongly influences olive oil quality because of its bitterness, which is a desirable trait. In addition, oleuropein possesses a wide range of pharmacological properties, including antioxidant, anti-inflammatory, and anti-cancer activities. In accordance, obtaining high oleuropein varieties is a main goal of molecular breeding programs. Here we use a transcriptomic approach to identify candidate genes belonging to the secoiridoid pathway in olive. From these candidates, we have functionally characterized the olive homologue of iridoid synthase (OeISY), an unusual terpene cyclase that couples an NAD (P)H-dependent 1,4-reduction step with a subsequent cyclization, and we provide evidence that OeISY likely generates the monoterpene scaffold of oleuropein in olive fruits. OeISY, the first pathway gene characterized for this type of secoiridoid, is a potential target for breeding programs in a high value secoiridoid-accumulating species.

  2. Making Mountains out of Molehills: Sediment Transport by the European Mole (Talpa europaea)

    NASA Astrophysics Data System (ADS)

    Milledge, D.; Loveless, J. C.; Warburton, J.; Densmore, A. L.

    2013-12-01

    Despite its widespread occurrence (across Europe and Eastern North America) the significance of the burrowing activity of the European Mole for sediment transport in the Northern Hemisphere has not been well quantified. In many areas this may have been the dominant mechanism of hillslope sediment transport over the last one to two millenia. The European Mole (Talpa europaea) is prevalent across the UK, particularly in fertile soils. It is highly fossorial, living almost its entire 3-6 year life in a network of tunnels that it maintains to catch prey. Moles can rapidly excavate large amounts of soil (~6 kg in 20 minutes) with waste soil generally pushed to the surface to form molehills. In this study we quantify sediment flux due to mole burrowing based on measured molehill sizes and geometries and estimates of mole hill production rates from time lapse photography. We examine the evolution of the molehills after production through repeat survey of in-situ molehills in the field and rainfall simulation experiments to accelerate degradation in the laboratory. Our initial findings suggest that: 1) molehill masses are generally log-normally distributed with a geometric mean ~1.4 kg; 2) moles move approximately 1.5 times as much soil as earthworms; and 3) the sediment flux due to moles is a non-linear function of the local slope.

  3. Genetic improvement of olive (Olea europaea L.) by conventional and in vitro biotechnology methods.

    PubMed

    Rugini, E; Cristofori, V; Silvestri, C

    2016-01-01

    In olive (Olea europaea L.) traditional methods of genetic improvement have up to now produced limited results. Intensification of olive growing requires appropriate new cultivars for fully mechanized groves, but among the large number of the traditional varieties very few are suitable. High-density and super high-density hedge row orchards require genotypes with reduced size, reduced apical dominance, a semi-erect growth habit, easy to propagate, resistant to abiotic and biotic stresses, with reliably high productivity and quality of both fruits and oil. Innovative strategies supported by molecular and biotechnological techniques are required to speed up novel hybridisation methods. Among traditional approaches the Gene Pool Method seems a reasonable option, but it requires availability of widely diverse germplasm from both cultivated and wild genotypes, supported by a detailed knowledge of their genetic relationships. The practice of "gene therapy" for the most important existing cultivars, combined with conventional methods, could accelerate achievement of the main goals, but efforts to overcome some technical and ideological obstacles are needed. The present review describes the benefits that olive and its products may obtain from genetic improvement using state of the art of conventional and unconventional methods, and includes progress made in the field of in vitro techniques. The uses of both traditional and modern technologies are discussed with recommendations.

  4. Isolation and characterization of a new hydroxytyrosol derivative from olive (Olea europaea) leaves.

    PubMed

    Paiva-Martins, Fátima; Pinto, Marisa

    2008-07-23

    A new secoiridoid compound was isolated from the leaves of Olea europaea. This compound, not previously identified, is the bis methylacetal of oleuropein aglycone, the 3,4-dihydroxyphenylethyl [(2,6-dimethoxy-3-ethylidene)-tetrahydropyran-4-yl]acetate (3,4-DHPEA-DETA), and was found in different olive cultivar phenolic extracts as one of the major secoiridoid components. This compound was shown to be easily transformed in acidic aqueous media into 3,4-DHPEA-EDA, the major polyphenolic compound found in olive oil, and permitted us to increase the yield of 3,4-DHPEA-EDA isolation from the olive leaf extract. The antiradical activity of this new compound, evaluated by scavenging of 2,2-diphenyl-1-picrylhydrazyl radicals, was much higher than the one found for 3,4-DHPEA-EDA or alpha-tocopherol. Results also call to attention the need for a careful identification of compounds by HPLC-MS, usually performed in acidic conditions.

  5. Triterpenes in the hexane extract of leaves of Olea europaea L.: analysis using 13C-NMR spectroscopy.

    PubMed

    Duquesnoy, Emilie; Castola, Vincent; Casanova, Joseph

    2007-01-01

    Two neutral triterpenes and a triterpene acid were identified and quantified directly, in the absence of any purification steps, in a precipitate obtained during the industrial extraction of the leaves of Olea europaea L. using 13C-NMR spectroscopy (spectrometer operating at 4.7 T equipped with a 10 mm probe). The method was optimised in order to reduce the duration of analysis with a routine NMR spectrometer. Together with long-chain linear compounds, erythrodiol, uvaol and oleanolic acid accounted for 27.3, 18.3 and 12.5% of the precipitate, respectively.

  6. The Skeletal Organic Matrix from Mediterranean Coral Balanophyllia europaea Influences Calcium Carbonate Precipitation

    PubMed Central

    Goffredo, Stefano; Vergni, Patrizia; Reggi, Michela; Caroselli, Erik; Sparla, Francesca; Levy, Oren; Dubinsky, Zvy; Falini, Giuseppe

    2011-01-01

    Scleractinian coral skeletons are made mainly of calcium carbonate in the form of aragonite. The mineral deposition occurs in a biological confined environment, but it is still a theme of discussion to what extent the calcification occurs under biological or environmental control. Hence, the shape, size and organization of skeletal crystals from the cellular level through the colony architecture, were attributed to factors as diverse as mineral supersaturation levels and organic mediation of crystal growth. The skeleton contains an intra-skeletal organic matrix (OM) of which only the water soluble component was chemically and physically characterized. In this work that OM from the skeleton of the Balanophyllia europaea, a solitary scleractinian coral endemic to the Mediterranean Sea, is studied in vitro with the aim of understanding its role in the mineralization of calcium carbonate. Mineralization of calcium carbonate was conducted by overgrowth experiments on coral skeleton and in calcium chloride solutions containing different ratios of water soluble and/or insoluble OM and of magnesium ions. The precipitates were characterized by diffractometric, spectroscopic and microscopic techniques. The results showed that both soluble and insoluble OM components influence calcium carbonate precipitation and that the effect is enhanced by their co-presence. The role of magnesium ions is also affected by the presence of the OM components. Thus, in vitro, OM influences calcium carbonate crystal morphology, aggregation and polymorphism as a function of its composition and of the content of magnesium ions in the precipitation media. This research, although does not resolve the controversy between environmental or biological control on the deposition of calcium carbonate in corals, sheds a light on the role of OM, which appears mediated by the presence of magnesium ions. PMID:21799830

  7. Polyphenols benefits of olive leaf (Olea europaea L) to human health.

    PubMed

    Vogel, Patrícia; Kasper Machado, Isabel; Garavaglia, Juliano; Zani, Valdeni Terezinha; de Souza, Daiana; Morelo Dal Bosco, Simone

    2014-12-17

    Introducción: Los compuestos fenólicos presentes en las hojas del olivo (olea europaea l.) conferir beneficios para la salud humana. Objetivos: Revisar la literatura científica sobre los beneficios de los polifenoles de hojas de olivo para la salud humana. Método: Revisión de la literatura en las bases de datos lilacs-bireme, scielo y medline para publicaciones en inglés, portugués y español con los descriptores “olea europaea”, “hojas de olivo”, “hoja de olivo”, “hojas de olivo extractos”, “los extractos de hoja de olivo”, “compuestos fenólicos”, “polifenoles”, “oleuropeína”, “composición química”, y “salud”. Se identificaron 92 artículos, pero sólo 38 en relación con los objetivos del estudio y 9 artículos citados en las obras se incluyeron debido a su relevancia. Resultados y discusión: Los compuestos fenólicos presentes en las hojas del olivo, especialmente la oleuropeína, se asocian a antioxidante, antihipertensivo, hipoglucemiante, actividad hipocolesterolémico y cardioprotector. además, los estudios asocian la oleuropeína a un efecto anti-inflamatorio en trauma de la médula ósea y como soporte en el tratamiento de la obesidad.

  8. Metabarcoding Analysis of Fungal Diversity in the Phyllosphere and Carposphere of Olive (Olea europaea).

    PubMed

    Abdelfattah, Ahmed; Li Destri Nicosia, Maria Giulia; Cacciola, Santa Olga; Droby, Samir; Schena, Leonardo

    2015-01-01

    The fungal diversity associated with leaves, flowers and fruits of olive (Olea europaea) was investigated in different phenological stages (May, June, October and December) using an implemented metabarcoding approach. It consisted of the 454 pyrosequencing of the fungal ITS2 region and the subsequent phylogenetic analysis of relevant genera along with validated reference sequences. Most sequences were identified up to the species level or were associated with a restricted number of related taxa enabling supported speculations regarding their biological role. Analyses revealed a rich fungal community with 195 different OTUs. Ascomycota was the dominating phyla representing 93.6% of the total number of detected sequences followed by unidentified fungi (3.6%) and Basidiomycota (2.8%). A higher level of diversity was revealed for leaves compared to flowers and fruits. Among plant pathogens the genus Colletotrichum represented by three species (C. godetiae syn. C. clavatum, C. acutatum s.s and C. karstii) was the most abundant on ripe fruits but it was also detected in other organs. Pseudocercospora cladosporioides was detected with a high frequency in all leaf samples and to a less extent in ripe fruits. A much lower relative frequency was revealed for Spilocaea oleagina and for other putative pathogens including Fusarium spp., Neofusicoccum spp., and Alternaria spp. Among non-pathogen taxa, Aureobasidium pullulans, the species complex of Cladosporium cladosporioides and Devriesia spp. were the most represented. This study highlights the existence of a complex fungal consortium including both phytopathogenic and potentially antagonistic microorganisms that can have a significant impact on olive productions.

  9. Identification and characterisation of Short Interspersed Nuclear Elements in the olive tree (Olea europaea L.) genome.

    PubMed

    Barghini, Elena; Mascagni, Flavia; Natali, Lucia; Giordani, Tommaso; Cavallini, Andrea

    2017-02-01

    Short Interspersed Nuclear Elements (SINEs) are nonautonomous retrotransposons in the genome of most eukaryotic species. While SINEs have been intensively investigated in humans and other animal systems, SINE identification has been carried out only in a limited number of plant species. This lack of information is apparent especially in non-model plants whose genome has not been sequenced yet. The aim of this work was to produce a specific bioinformatics pipeline for analysing second generation sequence reads of a non-model species and identifying SINEs. We have identified, for the first time, 227 putative SINEs of the olive tree (Olea europaea), that constitute one of the few sets of such sequences in dicotyledonous species. The identified SINEs ranged from 140 to 362 bp in length and were characterised with regard to the occurrence of the tRNA domain in their sequence. The majority of identified elements resulted in single copy or very lowly repeated, often in association with genic sequences. Analysis of sequence similarity allowed us to identify two major groups of SINEs showing different abundances in the olive tree genome, the former with sequence similarity to SINEs of Scrophulariaceae and Solanaceae and the latter to SINEs of Salicaceae. A comparison of sequence conservation between olive SINEs and LTR retrotransposon families suggested that SINE expansion in the genome occurred especially in very ancient times, before LTR retrotransposon expansion, and presumably before the separation of the rosids (to which Oleaceae belong) from the Asterids. Besides providing data on olive SINEs, our results demonstrate the suitability of the pipeline employed for SINE identification. Applying this pipeline will favour further structural and functional analyses on these relatively unknown elements to be performed also in other plant species, even in the absence of a reference genome, and will allow establishing general evolutionary patterns for this kind of repeats in

  10. Human absorption and metabolism of oleuropein and hydroxytyrosol ingested as olive (Olea europaea L.) leaf extract.

    PubMed

    de Bock, Martin; Thorstensen, Eric B; Derraik, José G B; Henderson, Harold V; Hofman, Paul L; Cutfield, Wayne S

    2013-11-01

    Phenolic compounds derived from the olive plant (Olea europaea L.), particularly hydroxytyrosol and oleuropein, have many beneficial effects in vitro. Olive leaves are the richest source of olive phenolic compounds, and olive leaf extract (OLE) is now a popular nutraceutical taken either as liquid or capsules. To quantify the bioavailability and metabolism of oleuropein and hydroxytyrosol when taken as OLE, nine volunteers (five males) aged 42.8 ± 7.4 years were randomized to receive either capsulated or liquid OLE as a single lower (51.1 mg oleuropein, 9.7 mg hydroxytyrosol) or higher (76.6 mg oleuropein, 14.5 mg hydroxytyrosol) dose, and then the opposite strength (but same formulation) a week later. Plasma and urine samples were collected at fixed intervals for 24 h post-ingestion. Phenolic content was analyzed by LC-ESI-MS/MS. Conjugated metabolites of hydroxytyrosol were the primary metabolites recovered in plasma and urine after OLE ingestion. Peak oleuropein concentrations in plasma were greater following ingestion of liquid than capsule preparations (0.47 versus 2.74 ng/mL; p = 0.004), but no such effect was observed for peak concentrations of conjugated (sulfated and glucuronidated) hydroxytyrosol (p = 0.94). However, the latter peak was reached earlier with liquid preparation (93 versus 64 min; p = 0.031). There was a gender effect on the bioavailability of phenolic compounds, with males displaying greater plasma area under the curve for conjugated hydroxytyrosol (11,600 versus 2550 ng/mL; p = 0.048). All conjugated hydroxytyrosol metabolites were recovered in the urine within 8 h. There was wide inter-individual variation. OLE effectively delivers oleuropein and hydroxytrosol metabolites to plasma in humans.

  11. Nondestructive evaluation of anthocyanins in olive (Olea europaea) fruits by in situ chlorophyll fluorescence spectroscopy.

    PubMed

    Agati, Giovanni; Pinelli, Patrizia; Cortés Ebner, Solange; Romani, Annalisa; Cartelat, Aurélie; Cerovic, Zoran G

    2005-03-09

    Anthocyanins (Anths) in olive (Olea europaea L.) fruits at different degrees of pigmentation were assessed nondestructively by measuring chlorophyll fluorescence (ChlF). The method is based on the comparison of the ChlF excitation spectra from olives with different pigmentation from green to green-red, reddish-purple, and purple. The logarithm of the ratio between the fluorescence excitation spectra (logFER) from two different colored zones gave the difference in the absorption spectrum between them. The absorbance spectrum derived from the logFER between a red olive and the same olive devoid of the skin showed the typical Anth green band (at 550 nm). It matched that recorded by microspectrophotometry on a single pulp cell and the in vitro absorbance spectrum of the olive skin extract. As expected, the in vivo Anths absorption maximum increased in intensity going from less to more mature olives and was higher in the sun-exposed olive side with respect to the sun-shaded side. Absolute quantitative nondestructive determination of Anths for each olive sample was obtained by the logFER calculated for two excitation wavelengths, 550 and 625 nm, of ChlF at 740 nm. Going from green to purple skin colors, the Log[ChlF(625)/ChlF(550)] was fairly well-correlated to the extract Anths concentration. Finally, the relationship between the Anths and the other main phenolics present in the olives analyzed by high-performance liquid chromatography was evaluated. The main result was a net increase of verbascoside with increasing Anths content. On the basis of our results, the development of a new rapid and noninvasive method for the monitoring of olive development and ripening can be envisaged.

  12. HPTLC Fingerprinting and Cholinesterase Inhibitory and Metal-Chelating Capacity of Various Citrus Cultivars and
Olea europaea

    PubMed Central

    Senol, Fatma Sezer; Ankli, Anita; Reich, Eike

    2016-01-01

    Summary Inhibitory activity of thirty-one ethanol extracts obtained from albedo, flavedo, seed and leaf parts of 17 cultivars of Citrus species from Turkey, the bark and leaves of Olea europaea L. from two locations (Turkey and Cyprus) as well as caffeic acid and hesperidin was tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), related to the pathogenesis of Alzheimer’s disease, using ELISA microtiter assays at 500 µg/mL. Metal-chelating capacity of the extracts was also determined. BChE inhibitory effect of the Citrus sp. extracts was from (7.7±0.7) to (70.3±1.1) %, whereas they did not show any inhibition against AChE. Cholinesterase inhibitory activity of the leaf and bark ethanol extracts of O. europaea was very weak ((10.2±3.1) to (15.0±2.3) %). The extracts had either no or low metal-chelating capacity at 500 µg/mL. HPTLC fingerprinting of the extracts, which indicated a similar phytochemical pattern, was also done using the standards of caffeic acid and hesperidin with weak cholinesterase inhibition. Among the screened extracts, the albedo extract of C. limon ‘Interdonato’, the flavedo extracts of ‘Kara Limon’ and ‘Cyprus’ cultivars and the seed extract of C. maxima appear to be promising as natural BChE inhibitors. PMID:27956858

  13. Oil, protein, antioxidants and free radical scavenging activity of stone from wild olive trees (Olea europaea L.).

    PubMed

    Hannachi, Hédia; Elfalleh, Walid; Marzouk, Sizaiem

    2013-05-01

    The wild olive trees or oleaster (var. sylvestris) and the cultivated olive trees (var. europaea) constitute the two botanical varieties of Olea europaea L. from Mediterranean. In this study, a partial chemical profile was conducted including the total lipids, the fatty acid profiles, soluble proteins, polyphenols, flavanoids contents and antioxidants activities of stone from six oleaster trees. The comparison was made by two olive cultivars cultivated in the same region. The oleaster and cultivar stones were richer in oil content having an average of 8.99 and 7.38 % dry weight basis (DW), respectively. Qualitatively, all studied oils have the same fatty acids profile with the oleic acid C18:1n-9 as the major fatty acid. The oleaster stone oils were richer in monounsaturated fatty acids having an average of 64.87%. They, also, richer in protein content with an average of 198.86 mg/g DW.The globulin is the major fraction, followed by the albumin, the prolamin and the glutemin fractions. The oleaster stone extracts contain polyphenols, flavonoids with an average of 151.14 and 11.91 mg gallic acid equivalent/100g of DW, respectively. The studied extracts showed antioxidant activity using the free radical scavenging activity determined by DPPH and ABTS. The unexploited oleaster stone seems to be a source of oil with good fatty acids balance, in protein and antioxidants metabolites and would be useful for the formulation of supplements and/or pharmaceutical ingredients.

  14. Plant-parasitic nematodes associated with olive tree (Olea europaea L.) with a focus on the Mediterranean Basin: a review.

    PubMed

    Ali, Nadine; Chapuis, Elodie; Tavoillot, Johannes; Mateille, Thierry

    2014-01-01

    The olive tree (Olea europaea ssp. europaea.) is one of the most ancient cultivated trees. It is an emblematic species owing to its ecological, economic and cultural importance, especially in the Mediterranean Basin. Plant-parasitic nematodes are major damaging pests on olive trees, mainly in nurseries. They significantly contribute to economic losses in the top-ten olive-producing countries in the world. However, the damages they induce in orchards and nurseries are specifically documented only in a few countries. This review aims to update knowledge about the olive-nematode pathosystem by: (1) updating the list of plant-parasitic nematodes associated with olive trees; (2) analysing their diversity (taxonomic level, trophic groups, dominance of taxa), which allowed us (i) to assess the richness observed in each country, and (ii) to exhibit and describe the most important taxa able to induce damages on olive trees such as: Meloidogyne, Pratylenchus, Helicotylenchus, Xiphinema, Tylenchulus, Rotylenchulus, Heterodera (distribution especially in the Mediterranean Basin, pathogenicity and reactions of olive trees); (3) describing some management strategies focusing on alternative control methods; (4) suggesting new approaches for controlling plant-parasitic nematodes based on the management of the diversity of their communities, which are structured by several environmental factors such as olive diversity (due to domestication of wild olive in the past, and to breeding now), cropping systems (from traditional to high-density orchards), irrigation, and terroirs.

  15. Transformation of beta-lycopene cyclase genes from Salicornia europaea and Arabidopsis conferred salt tolerance in Arabidopsis and tobacco.

    PubMed

    Chen, Xianyang; Han, Heping; Jiang, Ping; Nie, Lingling; Bao, Hexigeduleng; Fan, Pengxiang; Lv, Sulian; Feng, Juanjuan; Li, Yinxin

    2011-05-01

    Inhibition of lycopene cyclization decreased the salt tolerance of the euhalophyte Salicornia europaea L. We isolated a β-lycopene cyclase gene SeLCY from S. europaea and transformed it into Arabidopsis with stable expression. Transgenic Arabidopsis on post-germination exhibited enhanced tolerance to oxidative and salt stress. After 8 and 21 d recovery from 200 mM NaCl treatment, transgenic lines had a higher survival ratio than wild-type (WT) plants. Three-week-old transgenic plants treated with 200 mM NaCl showed better growth than the WT with higher photosystem activity and less H(2)O(2) accumulation. Determination of endogenous pigments of Arabidopsis treated with 200 mM NaCl for 0, 2 or 4 d demonstrated that the transgenic plants retained higher contents of carotenoids than the WT. Furthermore, to compare the difference between SeLCY and AtLCY from Arabidopsis, we used viral vector mediating ectopic expression of SeLCY and AtLCY in Nicotiana benthamiana. Although LCY genes transformation increased the salt tolerance in tobacco, there is no significant difference between SeLCY- and AtLCY-transformed plants. These findings indicate that SeLCY transgenic Arabidopsis improved salt tolerance by increasing synthesis of carotenoids, which impairs reactive oxygen species and protects the photosynthesis system under salt stress, and as a single gene, SeLCY functionally showed no advantage for salt tolerance improvement compared with AtLCY.

  16. Phytochemical properties and anti-proliferative activity of Olea europaea L. leaf extracts against pancreatic cancer cells.

    PubMed

    Goldsmith, Chloe D; Vuong, Quan V; Sadeqzadeh, Elham; Stathopoulos, Costas E; Roach, Paul D; Scarlett, Christopher J

    2015-07-17

    Olea europaea L. leaves are an agricultural waste product with a high concentration of phenolic compounds; especially oleuropein. Oleuropein has been shown to exhibit anti-proliferative activity against a number of cancer types. However, they have not been tested against pancreatic cancer, the fifth leading cause of cancer related death in Western countries. Therefore, water, 50% ethanol and 50% methanol extracts of Corregiola and Frantoio variety Olea europaea L. leaves were investigated for their total phenolic compounds, total flavonoids and oleuropein content, antioxidant capacity and anti-proliferative activity against MiaPaCa-2 pancreatic cancer cells. The extracts only had slight differences in their phytochemical properties, and at 100 and 200 μg/mL, all decreased the viability of the pancreatic cancer cells relative to controls. At 50 μg/mL, the water extract from the Corregiola leaves exhibited the highest anti-proliferative activity with the effect possibly due to early eluting HPLC peaks. For this reason, olive leaf extracts warrant further investigation into their potential anti-pancreatic cancer benefits.

  17. Adult neurogenesis in the hedgehog (Erinaceus concolor) and mole (Talpa europaea).

    PubMed

    Bartkowska, K; Turlejski, K; Grabiec, M; Ghazaryan, A; Yavruoyan, E; Djavadian, R L

    2010-01-01

    We investigated adult neurogenesis in two species of mammals belonging to the superorder Laurasiatheria, the southern white-breasted hedgehog (order Erinaceomorpha, species Erinaceus concolor) from Armenia and the European mole (order Soricomorpha, species Talpa europaea) from Poland. Neurogenesis in the brain of these species was examined immunohistochemically, using the endogenous markers doublecortin (DCX) and Ki-67, which are highly conserved among species. We found that in both the hedgehog and mole, like in the majority of earlier investigated mammals, neurogenesis continues in the subventricular zone (SVZ) of the lateral ventricles and in the dentate gyrus (DG). In the DG of both species, DCX-expressing cells and Ki-67-labeled cells were present in the subgranular and granular layers. In the mole, a strong bundle of DCX-labeled processes, presumably axons of granule cells, was observed in the center of the hilus. Proliferating cells (expressing Ki-67) were identified in the SVZ of lateral ventricles of both species, but neuronal precursor cells (expressing DCX) were also observed in the olfactory bulb (OB). In both species, the vast majority of cells expressing DCX in the OB were granule cells with radially orientated dendrites, although some periglomerular cells surrounding the glomeruli were also labeled. In addition, this paper is the first to show DCX-labeled fibers in the anterior commissure of the hedgehog and mole. These fibers must be axons of new neurons making interhemispheric connections between the two OB or piriform (olfactory) cortices. DCX-expressing neurons were observed in the striatum and piriform cortex of both hedgehog and mole. We postulate that in both species a fraction of cells newly generated in the SVZ migrates along the rostral migratory stream to the piriform cortex. This pattern of migration resembles that of the 'second-wave neurons' generated during embryonal development of the neocortex rather than the pattern observed during

  18. Overview of EPA Research on Drinking Water Distribution System Nitrification

    EPA Science Inventory

    Results from USEPA research investigating drinking water distribution system nitrification will be presented. The two research areas include: (1) monochloramine disinfection kinetics of Nitrosomonas europaea using Propidium Monoazide Quantitative Real-time PCR (PMA-qPCR) and (2...

  19. Monochloramine Cometabolism by Nitrifying Biofilm Relevant to Drinking Water

    EPA Science Inventory

    Recently, biological monochloramine removal (i.e., cometabolism) by a pure culture ammonia–oxidizing bacteria, Nitrosomonas europaea, and a nitrifying mixed–culture have been shown to increase monochloramine demand. Although important, these previous suspended culture batch kine...

  20. Direct chemical profiling of olive (Olea europaea) fruit epicuticular waxes by direct electrospray-ultrahigh resolution mass spectrometry.

    PubMed

    Vichi, Stefania; Cortés-Francisco, Nuria; Romero, Agustí; Caixach, Josep

    2015-03-01

    In the present paper, an electrospray ionization (ESI)-Orbitrap method is proposed for the direct chemical profiling of epicuticular wax (EW) from Olea europaea fruit. It constitutes a rapid and efficient tool suitable for a wide-ranging screening of a large number of samples. In a few minutes, the method provides a comprehensive characterization of total EW extracts, based on the molecular formula of their components. Accurate mass measurements are obtained by ultrahigh resolution mass spectrometry, and compositional restrictions are set on the basis of the information available from previous studies of olive EW. By alternating positive and negative ESI modes within the same analysis, complementary results are obtained and a wide range of chemical species is covered. This provides a detailed compositional overview that otherwise would only be available by applying multiple analytical techniques.

  1. Selective ultrasound-enhanced enzymatic hydrolysis of oleuropein to its aglycon in olive (Olea europaea L.) leaf extracts.

    PubMed

    Delgado-Povedano, María Del Mar; Priego-Capote, Feliciano; Luque de Castro, María Dolores

    2017-04-01

    Hydrolysis of oleuropein, the main phenol in olive (Olea europaea L.) leaf extracts, to oleuropein aglycon and other subsequent products in the hydrolytic pathway can be catalyzed by different enzymes. Three of the most used hydrolases were assayed to catalyze the process, and β-glucosidase from Aspergillus niger was selected. Acceleration of the enzymatic hydrolysis by ultrasound (US) was studied using a Box-Behnken design (duty cycle, amplitude, cycle time) and an oleuropein standard, and the optimum US conditions for achieving maximum yield of oleuropein aglycon were 0.5s/s duty cycle, 50% amplitude and 45s cycle. The method was applied to obtain oleuropein aglycon from commercial and laboratory extracts from olive leaves, which may have a pharmacological use as deduced by its healthy properties. The kinetics of the US-assisted enzymatic hydrolysis was monitored by analysis of the target compounds using liquid chromatography-tandem mass spectrometry.

  2. The role of temperature in the onset of the Olea europaea L. pollen season in southwestern Spain.

    PubMed

    Galán, C; García-Mozo, H; Cariñanos, P; Alcázar, P; Domínguez-Vilches, E

    2001-02-01

    Temperature is one of the main factors affecting the flowering of Mediterranean trees. In the case of Olea europaea L., a low-temperature period prior to bud development is essential to interrupt dormancy. After that, and once a base temperature is reached, the plant accumulates heat until flowering starts. Different methods of obtaining the best-forecast model for the onset date of the O. europaea pollen season, using temperature as the predictive parameter, are proposed in this paper. An 18-year pollen and climatic data series (1982-1999) from Cordoba (Spain) was used to perform the study. First a multiple-regression analysis using 15-day average temperatures from the period prior to flowering time was tested. Second, three heat-summation methods were used, determining the the quantities heat units (HU): accumulated daily mean temperature after deducting a threshold, growing degree-days (GDD): proposed by Snyder [J Agric Meteorol 35:353-358 (1985)] as a measure of physiological time, and accumulated maximum temperature. In the first two, the optimum base temperature selected for heat accumulation was 12.5 degrees C. The multiple-regression equation for 1999 gives a 7-day delay from the observed date. The most accurate results were obtained with the GDD method, with a difference of only 4.7 days between predicted and observed dates. The average heat accumulation expressed as GDD was 209.9 degrees C days. The HU method also gives good results, with no significant statistical differences between predictions and observations.

  3. Antioxidant activity and chemical components as potential anticancer agents in the olive leaf (Olea europaea L. cv Leccino.) decoction.

    PubMed

    De Marino, Simona; Festa, Carmen; Zollo, Franco; Nini, Antonella; Antenucci, Lina; Raimo, Gennaro; Iorizzi, Maria

    2014-01-01

    Epidemiological studies have shown that a reduced risk of chronic diseases such as cancer and cardiovascular diseases is correlated with a regular consumption of fruits and vegetable, many of which are rich in polyphenols. The additive and synergistic effect of phytochemicals in fruits and vegetables may reduce chronic diseases related to oxidative stress in human body. Olea europaea L. leaf are rich in phenolic components, which have been proposed to play a role in cancer prevention. The purpose of this study was to identify the main components in the Olea europaea L. leaf (cv. Leccino) preserved during the decoction preparation, in order to delineate the antioxidant activities of the crude extracts and its isolated compounds by using different in vitro assays including DPPH radicalscavenging capacity, total antioxidant capacity (TAC), xanthine oxidase (XO) inhibitory effect and the ability to delay the linoleic acid peroxidation process (ALP). The aqueous decoction was partitioned obtaining four extracts and the n-butanol extract showed the highest antioxidant activity and the highest total phenolic content. Phytochemical investigation leads to the isolation of thirteen secondary metabolites including simple phenolics, flavonoids, secoiridoids whose structures were elucidated by spectroscopic data (1D and 2D NMR) and spectrometric techniques. A significant free radical scavenging effect against DPPH has been evidenced in fraxamoside (1) (EC50 62.6 µM) and taxifolin (5) (EC50 50.0 µM), isolated for the first time from the water decoction. The most active compound in the TAC evaluation, was the 3,4 dihydro-phenyl glycol (8) (0.90 caffeic acid equiv.) while taxifolin and fraxamoside resulted as the most efficient inhibitors of XO activity (IC50 2.7 and 5.2 µM, respectively). Secoxyloganin (4), oleuropein (2) and tyrosol (6) showed the highest ALP activity. This study adds to the growing body of data supporting the bioactivities of phytochemicals and their

  4. Wound repair potential of Olea europaea L. leaf extracts revealed by in vivo experimental models and comparative evaluation of the extracts' antioxidant activity.

    PubMed

    Koca, Ufuk; Süntar, Ipek; Akkol, Esra Küpeli; Yilmazer, Demet; Alper, Murat

    2011-01-01

    Leaves and fruits of Olea europaea L. (olive) have been used externally as an emollient for skin ulcers and for healing of inflammatory wounds. n-Hexane and aqueous extracts, prepared from the dried leaves of olive, were evaluated for their wound healing activity by using in vivo wound models of linear incision and circular excision in comparison with the reference ointment Madecassol® (Bayer, Istanbul, Turkey). The group of animals treated with the aqueous extract demonstrated increased contraction (87.1%) on excision and a significant increase in wound tensile strength (34.8%) on incision models compared to the other groups. Moreover, the antioxidant activity assay showed that aqueous extract has higher scavenging ability than the n-hexane extract. According to the experimental data, the aqueous extract of O. europaea leaves displayed wound healing activity. Secoiridoid oleuropein (4.6059%) was identified as the major active compound according to high-performance liquid chromatography analysis of the aqueous extract.

  5. The Effects of Amine Based Missile Fuels on the Activated Sludge Process.

    DTIC Science & Technology

    1979-10-01

    Reference 17) used neat hydrazine as a selective inhibitor in their studies with Nitrosomonas europaea to show that hydroxylamine is an intermediate...of nitrite oxidation. That hydrazine was more toxic to Nitrobacter sp. than Nitrosomonas sp. in activated sludge was in general agreement with Meyerhof...Reference 16) who studied pure cultures of Nitrosomonas sp. and found 20-percent inhibition of ammonia oxidation at 32 mg/t. Yoshida and Alexander

  6. Effects of Nitrogen Dioxide and Anoxia on Global Gene and Protein Expression in Long-Term Continuous Cultures of Nitrosomonas eutropha C91

    PubMed Central

    Kartal, Boran; Wessels, Hans J. C. T.; van der Biezen, Erwin; Francoijs, Kees-Jan; Jetten, Mike S. M.; Klotz, Martin G.

    2012-01-01

    Nitrosomonas eutropha is an ammonia-oxidizing betaproteobacterium found in environments with high ammonium levels, such as wastewater treatment plants. The effects of NO2 on gene and protein expression under oxic and anoxic conditions were determined by maintaining N. eutropha strain C91 in a chemostat fed with ammonium under oxic, oxic-plus-NO2, and anoxic-plus-NO2 culture conditions. Cells remained viable but ceased growing under anoxia; hence, the chemostat was switched from continuous to batch cultivation to retain biomass. After several weeks under each condition, biomass was harvested for total mRNA and protein isolation. Exposure of N. eutropha C91 to NO2 under either oxic or anoxic conditions led to a decrease in proteins involved in N and C assimilation and storage and an increase in proteins involved in energy conservation, including ammonia monooxygenase (AmoCAB). Exposure to anoxia plus NO2 resulted in increased representation of proteins and transcripts reflective of an energy-deprived state. Several proteins implicated in N-oxide metabolism were expressed and remained unchanged throughout the experiment, except for NorCB nitric oxide reductase, which was not detected in the proteome. Rather, NorY nitric oxide reductase was expressed under oxic-plus-NO2 and anoxic-plus-NO2 conditions. The results indicate that exposure to NO2 results in an energy-deprived state of N. eutropha C91 and that anaerobic growth could not be supported with NO2 as an oxidant. PMID:22562996

  7. Quantification of Nitrosomonas oligotropha-Like Ammonia-Oxidizing Bacteria and Nitrospira spp. from Full-Scale Wastewater Treatment Plants by Competitive PCR

    PubMed Central

    Dionisi, Hebe M.; Layton, Alice C.; Harms, Gerda; Gregory, Igrid R.; Robinson, Kevin G.; Sayler, Gary S.

    2002-01-01

    Utilizing the principle of competitive PCR, we developed two assays to enumerate Nitrosomonas oligotropha-like ammonia-oxidizing bacteria and nitrite-oxidizing bacteria belonging to the genus Nitrospira. The specificities of two primer sets, which were designed for two target regions, the amoA gene and Nitrospira 16S ribosomal DNA (rDNA), were verified by DNA sequencing. Both assays were optimized and applied to full-scale, activated sludge wastewater treatment plant (WWTP) samples. If it was assumed that there was an average of 3.6 copies of 16S rDNA per cell in the total population and two copies of the amoA gene per ammonia-oxidizing bacterial cell, the ammonia oxidizers examined represented 0.0033% ± 0.0022% of the total bacterial population in a municipal WWTP. N. oligotropha-like ammonia-oxidizing bacteria were not detected in an industrial WWTP. If it was assumed that there was one copy of the 16S rDNA gene per nitrite-oxidizing bacterial cell, Nitrospira spp. represented 0.39% ± 0.28% of the biosludge population in the municipal WWTP and 0.37% ± 0.23% of the population in the industrial WWTP. The number of Nitrospira sp. cells in the municipal WWTP was more than 62 times greater than the number of N. oligotropha-like cells, based on a competitive PCR analysis. The results of this study extended our knowledge of the comparative compositions of nitrifying bacterial populations in wastewater treatment systems. Importantly, they also demonstrated that we were able to quantify these populations, which ultimately will be required for accurate prediction of process performance and stability for cost-effective design and operation of WWTPs. PMID:11772633

  8. Community structure variability of Uropodina mites (Acari: Mesostigmata) in nests of the common mole, Talpa europaea, in Central Europe.

    PubMed

    Napierała, Agnieszka; Mądra, Anna; Leszczyńska-Deja, Kornelia; Gwiazdowicz, Dariusz J; Gołdyn, Bartłomiej; Błoszyk, Jerzy

    2016-04-01

    Underground nests of Talpa europaea, known as the common mole, are very specific microhabitats, which are also quite often inhabited by various groups of arthropods. Mites from the suborder Uropodina (Acari: Mesostigmata) are only one of them. One could expect that mole nests that are closely located are inhabited by communities of arthropods with similar species composition and structure. However, results of empirical studies clearly show that even nests which are close to each other can be different both in terms of the species composition and abundance of Uropodina communities. So far, little is known about the factors that can cause these differences. The major aim of this study was to identify factors determining species composition, abundance, and community structure of Uropodina communities in mole nests. The study is based on material collected during a long-term investigation conducted in western parts of Poland. The results indicate that the two most important factors influencing species composition and abundance of Uropodina communities in mole nests are nest-building material and depth at which nests are located. Composition of Uropodina communities in nests of moles was also compared with that of other microhabitats (e.g. rotten wood, forest litter, soil) based on data from 4421 samples collected in Poland. Communities of this habitat prove most similar to these of open areas, especially meadows, as well as some forest types.

  9. De Novo Transcriptome Sequencing of Olea europaea L. to Identify Genes Involved in the Development of the Pollen Tube.

    PubMed

    Iaria, Domenico; Chiappetta, Adriana; Muzzalupo, Innocenzo

    2016-01-01

    In olive (Olea europaea L.), the processes controlling self-incompatibility are still unclear and the molecular basis underlying this process are still not fully characterized. In order to determine compatibility relationships, using next-generation sequencing techniques and a de novo transcriptome assembly strategy, we show that pollen tubes from different olive plants, grown in vitro in a medium containing its own pistil and in combination pollen/pistil from self-sterile and self-fertile cultivars, have a distinct gene expression profile and many of the differentially expressed sequences between the samples fall within gene families involved in the development of the pollen tube, such as lipase, carboxylesterase, pectinesterase, pectin methylesterase, and callose synthase. Moreover, different genes involved in signal transduction, transcription, and growth are overrepresented. The analysis also allowed us to identify members in actin and actin depolymerization factor and fibrin gene family and member of the Ca(2+) binding gene family related to the development and polarization of pollen apical tip. The whole transcriptomic analysis, through the identification of the differentially expressed transcripts set and an extended functional annotation analysis, will lead to a better understanding of the mechanisms of pollen germination and pollen tube growth in the olive.

  10. Air pollution effects on the leaf structure of two injury resistant species: Eucalyptus camaldulensis and Olea europaea L

    SciTech Connect

    Christodoulakis, N.S.; Koutsogeorgopoulou, L. )

    1991-09-01

    The release of toxic gases as well as of particulate pollutants into the atmosphere is a major side effect of the human industrial, agricultural and domestic activities. The impact of these compounds on the various life forms of our planet seems to be very serious. Investigations of plant species resistant to pollution-induced injuries do have a meaning. The introduction of these species will improve air quality and establish a moderate rate of primary productivity in the handicapped regions. That is why data concerning an evergreen sclerophyllous species which does not present structural modifications and organelle destruction although forced to be a dweller of a partition isle in a heavily polluted, traffic-loaded main street of the smog-suffering city of Athens, Greece, seemed very interesting. In this paper, further investigation is presented. Two common, species were studied. The first, Eucalyptus camaldulensis, a huge tree once imported to Europe from Australia as a marsh-drier in an effort to control malaria, is a drought enduring species mostly known for the essential oils accumulated in its leaves. The second, Olea europaea L. var oleaster Brot, is a sclerophyllous tree growing wild in chaparall formations in Greece.

  11. The amino acid sequence of Ole e I, the major allergen from olive tree (Olea europaea) pollen.

    PubMed

    Villalba, M; Batanero, E; López-Otín, C; Sánchez, L M; Monsalve, R I; González de la Peña, M A; Lahoz, C; Rodríguez, R

    1993-09-15

    The complete primary structure of the major allergen from Olea europaea (olive tree) pollen, Ole e I (IUIS nomenclature), has been determined. The amino acid sequence was established by automated Edman degradation of the reduced and alkylated molecule as well as of selected fragments obtained by proteolytic digestions. Ole e I contains a single polypeptide chain of 145 amino acid residues with a calculated molecular mass of 16331 Da. No free sulfhydryl groups have been detected in the native protein. The molecule contains a putative glycosylation site. A high degree of microheterogeneity has been observed, mainly centered in the first 33% of the molecule. Comparison of Ole e I sequence with protein sequence databases showed no similarity with other known allergens. However, it has a 36% and 38% sequence identity with the putative polypeptide structures, deduced, respectively, from nucleotide sequences of genes isolated from tomato anthers and corn pollen, which have been suggested to be involved in the growing of the pollen tube. Therefore, the olive tree allergen may be a constitutive protein of the pollen involved in reproductive functions.

  12. Freezing avoidance by supercooling in Olea europaea cultivars: the role of apoplastic water, solute content and cell wall rigidity.

    PubMed

    Arias, Nadia S; Bucci, Sandra J; Scholz, Fabian G; Goldstein, Guillermo

    2015-10-01

    Plants can avoid freezing damage by preventing extracellular ice formation below the equilibrium freezing temperature (supercooling). We used Olea europaea cultivars to assess which traits contribute to avoid ice nucleation at sub-zero temperatures. Seasonal leaf water relations, non-structural carbohydrates, nitrogen and tissue damage and ice nucleation temperatures in different plant parts were determined in five cultivars growing in the Patagonian cold desert. Ice seeding in roots occurred at higher temperatures than in stems and leaves. Leaves of cold acclimated cultivars supercooled down to -13 °C, substantially lower than the minimum air temperatures observed in the study site. During winter, leaf ice nucleation and leaf freezing damage (LT50 ) occurred at similar temperatures, typical of plant tissues that supercool. Higher leaf density and cell wall rigidity were observed during winter, consistent with a substantial acclimation to sub-zero temperatures. Larger supercooling capacity and lower LT50 were observed in cold-acclimated cultivars with higher osmotically active solute content, higher tissue elastic adjustments and lower apoplastic water. Irreversible leaf damage was only observed in laboratory experiments at very low temperatures, but not in the field. A comparative analysis of closely related plants avoids phylogenetic independence bias in a comparative study of adaptations to survive low temperatures.

  13. Valuable Nutrients and Functional Bioactives in Different Parts of Olive (Olea europaea L.)—A Review

    PubMed Central

    Ghanbari, Rahele; Anwar, Farooq; Alkharfy, Khalid M.; Gilani, Anwarul-Hassan; Saari, Nazamid

    2012-01-01

    The Olive tree (Olea europaea L.), a native of the Mediterranean basin and parts of Asia, is now widely cultivated in many other parts of the world for production of olive oil and table olives. Olive is a rich source of valuable nutrients and bioactives of medicinal and therapeutic interest. Olive fruit contains appreciable concentration, 1–3% of fresh pulp weight, of hydrophilic (phenolic acids, phenolic alchohols, flavonoids and secoiridoids) and lipophilic (cresols) phenolic compounds that are known to possess multiple biological activities such as antioxidant, anticarcinogenic, antiinflammatory, antimicrobial, antihypertensive, antidyslipidemic, cardiotonic, laxative, and antiplatelet. Other important compounds present in olive fruit are pectin, organic acids, and pigments. Virgin olive oil (VOO), extracted mechanically from the fruit, is also very popular for its nutritive and health-promoting potential, especially against cardiovascular disorders due to the presence of high levels of monounsaturates and other valuable minor components such as phenolics, phytosterols, tocopherols, carotenoids, chlorophyll and squalene. The cultivar, area of production, harvest time, and the processing techniques employed are some of the factors shown to influence the composition of olive fruit and olive oil. This review focuses comprehensively on the nutrients and high-value bioactives profile as well as medicinal and functional aspects of different parts of olives and its byproducts. Various factors affecting the composition of this food commodity of medicinal value are also discussed. PMID:22489153

  14. Endophytic and rhizosphere bacteria associated with the roots of the halophyte Salicornia europaea L. - community structure and metabolic potential.

    PubMed

    Szymańska, Sonia; Płociniczak, Tomasz; Piotrowska-Seget, Zofia; Hrynkiewicz, Katarzyna

    2016-11-01

    The main objective of our study was to assess density and diversity of rhizosphere (R) and endophytic (E) microorganisms associated with the halophyte S. europaea. Microorganisms were isolated from two saline sites (S1: 55dSm(-1), anthropogenic origin; S2: 112dSm(-1), natural salinity) located in central Poland and compared with microbial populations in the soil (S) using culture-independent (phospholipid fatty acids analysis, PLFA) and culture-dependent techniques. The endophytic and rhizosphere bacteria were identified and screened for nifH and acdS genes, and their metabolic properties were assessed. Strains with the potential to promote plant growth were selected for further study. PLFA analysis revealed that Gram-negative bacteria were dominant at both saline test sites; the total microbial biomass depended on the site (S1E>S). In contrast, culture-dependent techniques revealed that Gram-positive bacteria (Actinobacteria and Firmicutes) were dominant (S1: E-77.3%, R-86.3% and S2: E-59.1%, R-87.5%). Proteobacteria were observed in the rhizosphere at the lowest frequency (S1: 13.7% and S2: 12.5%). Greater salinity decreased the range and specificity of metabolic activity among the endophytes. These conditions also resulted in a broader spectrum of metabolic abilities in rhizobacteria; however, these metabolic processes were present at lower levels.

  15. Salicornia europaea L. Na⁺/H⁺ antiporter gene improves salt tolerance in transgenic alfalfa (Medicago sativa L.).

    PubMed

    Zhang, L Q; Niu, Y D; Huridu, H; Hao, J F; Qi, Z; Hasi, A

    2014-07-24

    In order to obtain a salt-tolerant perennial alfalfa (Medicago sativa L.), we transferred the halophyte Salicornia europaea L. Na(+)/H(+) antiporter gene, SeNHX1, to alfalfa by using the Agrobacterium-mediated transformation method. The transformants were confirmed by both PCR and RT-PCR analyses. Of 197 plants that were obtained after transformation, 36 were positive by PCR analysis using 2 primer pairs for the CaMV35S-SeNHX1 and SeNHX1-Nos fragments; 6 plants survived in a greenhouse. RT-PCR analysis revealed that SeNHX1 was expressed in 5 plants. The resultant transgenic alfalfa had better salt tolerance. After stress treatment for 21 days with 0.6% NaCl, the chlorophyll and MDA contents in transgenic plants were lower, but proline content and SOD, POD, and CAT activities were higher than those in wild-type plants. These results suggest that the salt tolerance of transgenic alfalfa was improved by the overexpression of the SeNHX1 gene.

  16. Influence of high concentrations of mineral salts on production process and NaCl accumulation by Salicornia europaea plants as a constituent of the LSS phototroph link

    NASA Astrophysics Data System (ADS)

    Tikhomirova, N. A.; Ushakova, S. A.; Kovaleva, N. P.; Gribovskaya, I. V.; Tikhomirov, A. A.

    Use of halophytes (salt-tolerant vegetation), in a particular vegetable Salicornia europaea plants which are capable of utilizing NaCl in rather high concentrations, is one of possible means of NaCl incorporation into mass exchange of bioregenerative life support systems. In preliminary experiments it was shown that S. europaea plants, basically, could grow on urine pretreated with physicochemical processing and urease-enzyme decomposing of urea with the subsequent ammonia distillation. But at the same time inhibition of the growth process of the plants was observed. The purpose of the given work was to find out the influence of excessive quantities of some mineral elements contained in products of physicochemical processing of urine on the production process and NaCl accumulation by S. europaea plants. As the content of mineral salts in the human liquid wastes (urine) changed within certain limits, two variants of experimental solutions were examined. In the first variant, the concentration of mineral salts was equivalent to the minimum salt content in the urine and was: K - 1.5 g/l, P - 0.5 g/l, S - 0.5 g/l, Mg - 0.07 g/l, Ca - 0.2 g/l. In the second experimental variant, the content of mineral salts corresponded to the maximum salt content in urine and was the following: K - 3.0 g/l, P - 0.7 g/l, S - 1.2 g/l, Mg - 0.2 g/l, Ca - 0.97 g/l. As the control, the Tokarev nutrient solution containing nitrogen in the form of a urea, and the Knop nutrient solution with nitrogen in the nitrate form were used. N quantity in all four variants made up 177 mg/l. Air temperature was 24 °C, illumination was continuous. Light intensity was 690 μmol/m 2s of photosynthetically active radiation. NaCl concentration in solutions was 1%. Our researches showed that the dry aboveground biomass of an average plant of the first variant practically did not differ from the control and totaled 11 g. In the second variant, S. europaea productivity decreased and the dry aboveground biomass

  17. Influence of high concentrations of mineral salts on production process and NaCl accumulation by Salicornia europaea plants as a constituent of the LSS phototroph link.

    PubMed

    Tikhomirova, N A; Ushakova, S A; Kovaleva, N P; Gribovskaya, I V; Tikhomirov, A A

    2005-01-01

    Use of halophytes (salt-tolerant vegetation), in a particular vegetable Salicornia europaea plants which are capable of utilizing NaCl in rather high concentrations, is one of possible means of NaCl incorporation into mass exchange of bioregenerative life support systems. In preliminary experiments it was shown that S. europaea plants, basically, could grow on urine pretreated with physicochemical processing and urease-enzyme decomposing of urea with the subsequent ammonia distillation. But at the same time inhibition of the growth process of the plants was observed. The purpose of the given work was to find out the influence of excessive quantities of some mineral elements contained in products of physicochemical processing of urine on the production process and NaCl accumulation by S. europaea plants. As the content of mineral salts in the human liquid wastes (urine) changed within certain limits, two variants of experimental solutions were examined. In the first variant, the concentration of mineral salts was equivalent to the minimum salt content in the urine and was: K - 1.5 g/l, P - 0.5 g/l, S - 0.5 g/l, Mg - 0.07 g/l, Ca - 0.2 g/l. In the second experimental variant, the content of mineral salts corresponded to the maximum salt content in urine and was the following: K - 3.0 g/l, P - 0.7 g/l, S - 1.2 g/l, Mg - 0.2 g/l, Ca - 0.97 g/l. As the control, the Tokarev nutrient solution containing nitrogen in the form of a urea, and the Knop nutrient solution with nitrogen in the nitrate form were used. N quantity in all four variants made up 177 mg/l. Air temperature was 24 degrees C, illumination was continuous. Light intensity was 690 micromoles/m2s of photosynthetically active radiation. NaCl concentration in solutions was 1%. Our researches showed that the dry aboveground biomass of an average plant of the first variant practically did not differ from the control and totaled 11 g. In the second variant, S. europaea productivity decreased and the dry aboveground

  18. Mass mortality events of the coral Balanophyllia europaea (Scleractinia, Dendrophylliidae) in the Mljet National Park (eastern Adriatic Sea) caused by sea temperature anomalies

    NASA Astrophysics Data System (ADS)

    Kružić, P.; Popijač, A.

    2015-03-01

    Recurrent climate-induced mass mortalities of marine animals have been recorded in the Mediterranean Sea over the past 15 years. These mortality outbreaks have been associated with positive thermal anomalies. In this study, we assessed long-term (from 2003 to 2013) responses of the temperate coral Balanophyllia europaea to increasing seawater temperatures in the Mljet National Park in the Adriatic Sea (Northern Mediterranean Sea) and described the relationship between recurrent mortality events and sea temperature regimes in the southern Adriatic Sea. Our results indicate that polyp bleaching and tissue necrosis caused the observed mortality. The first observations of B. europaea mortality within the study area in the Mljet NP were in early September 2003. The Mediterranean area experienced high temperatures and hydrographic stability over a period of several weeks throughout that summer, which resulted in a mass mortality event. In the Mljet National Park, the highest impact of mass mortality started during the exceptionally hot summer of 2012, representing one of the most severe mass mortality events ever observed in the Adriatic Sea. In 2012, sea temperatures at a 5 m depth during the summer period (from June to September) ranged from 24.44 to 30.16 °C in the Mljet NP. The northern sites in the Mljet NP were highly impacted, with up to 80 % of B. europaea specimens affected by necrosis, while the southern sites displayed the highest impact, with 90-100 % of affected individuals. Without any coral adaptation to warming and under the present climate-warming trend, new mass mortality events may occur in the near future, possibly causing a major coral biodiversity crisis in the Mediterranean Sea.

  19. Effect of NaCl Concentration on Productivity and Mineral Composition of Salicrnia europaea as a Plausible Representative of LSS Photosynthesizing Component

    NASA Astrophysics Data System (ADS)

    Ushakova, S.; Kovaleva, N.; Gribovskaya, I.; Dolgushev, V.; Tikhomirova, N.

    In man-made ecosystems the problem of deadlock wastes generated among other reasons by accumulation of NaCl-containing human liquid wastes has no efficient solution, yet. This retards development of man-made highly closed biological ecosystems where the deadlock wastes must be minimized. A possible solution of the problem is to select plant species capable of utilizing NaCl with sufficiently high concentrations, being edible by humans and featuring high productivity. So far the higher plants used in life support systems were either sensitive to salination (wheat, many bean species, carrots, potatoes, corn) or relatively salt-resistant (barley, beet roots, spinach). Salicornia europaea whose overground part is fully edible for humans is one of most acceptable for this purpose. By the literature evidence this plant is capable of accumulating up to 50% NaCl in terms of dry matter. In addition, excessive accumulation of sodium ions should bring forth increase of carry-out of potassium ions and other biogenous elements. The aim of this work is to study the feasibility of using S. europaea species in growth chambers to involve NaCl into matter turnover. Plants were grown in vegetation chambers under the irradiance of 100 W/m 2 PAR and the temperature of air 24?? by two methods. The first method was to cultivate on a substrate which was peat: without salination (1 version) and with addition of 3.5% (2 version) or 7% NaCl (3 version) in terms of dry peat mass. The second method was to cultivate on an aqueous solution with addition of a complete set of nutrients and, depending on the version, containing ? NaCl at the concentration of 0%, 1% or 2%. The study showed that addition of NaCl to the substrate or to the solution resulted in formation of more succulent plants which considerably increased their biomass. The amount of NaCl uptake was the highest in the plants grown in aqueous cultu e, its part in the dry matter was not less than 30%.r As the sodium uptake increased

  20. Thriving at the limit: Differential reproductive performance in range-edge populations of a Mediterranean sclerophyll (Olea europaea)

    NASA Astrophysics Data System (ADS)

    Granado-Yela, Carlos; Balaguer, Luis; García-Verdugo, Carlos; Carrillo, Katty; Méndez, Marcos

    2013-10-01

    Peripheral populations are often lumped together on the assumption of thriving in marginal habitats where reproductive performance is compromised. We have tested this hypothesis in peripheral populations of wild olive tree (Olea europaea L.) presumably limited by different factors at the westernmost limit of the species range. Additionally, we hypothesized that differences in reproductive outcome among populations are better explained by site-specific environmental conditions (PAR, soil water, soil nutrients, air humidity and air temperature) than by differences in phenotypic traits (tree size and leaf traits). To test these hypotheses, we assessed the number of flowering trees, the flowering intensity, fruit set and seed viability in eight populations for three consecutive years. Our findings provided sufficient evidence to reject the first hypothesis. Peripheral populations that occur under oceanic conditions, resembling the Tertiary subtropical climate, consistently presented higher values for all components of reproductive performance than those at the thermal and rainfall tolerance limits. In support of our second hypothesis, the variation in reproductive performance among populations was primarily accounted for by local environmental conditions. Leaf traits, however, also explained reproductive variation but to a lesser extent. Finally, we found that small changes in tree size may cause large differences in reproductive performance. This close relationship between tree size and reproductive performance suggests that any impact on population size structure would likely jeopardize persistence and expansion at the range edge. Our results suggest that reproductive performance of wild olive trees was not shaped by the population geographic position within the species range, but by the interaction between local environment, as the main driver, and individual phenotypic traits.

  1. The relevance of gene flow in metapopulation dynamics of an oceanic island endemic, Olea europaea subsp. guanchica.

    PubMed

    García-Verdugo, Carlos; Forrest, Alan D; Fay, Michael F; Vargas, Pablo

    2010-12-01

    Theoretical and empirical studies suggest that geographical isolation and extinction-recolonization dynamics are two factors causing strong genetic structure in metapopulations, but their consequences in species with high dispersal abilities have not been tested at large scales. Here, we investigated the effect of population age structure and isolation by distance in the patterns of genetic diversity in a wind-pollinated, zoochorous tree (Olea europaea subsp. guanchica) sporadically affected by volcanic events across the Canarian archipelago. Genetic variation was assessed at six nuclear microsatellites (nDNA) and six chloroplast fragments (cpDNA) in nine subpopulations sampled on four oceanic islands. Subpopulations occurring on more recent substrates were more differentiated than those on older substrates, but within-subpopulation genetic diversity was not significantly different between age groups for any type of marker. Isolation-by-distance differentiation was observed for nDNA but not for cpDNA, in agreement with other metapopulation studies. Contrary to the general trend for island systems, between-island differentiation was extremely low, and lower than differentiation between subpopulations on the same island. The pollen-to-seed ratio was close to one, two orders of magnitude lower than the average estimated for other wind-pollinated, animal-dispersed plants. Our results showed that population turnover and geographical isolation increased genetic differentiation relative to an island model at equilibrium, but overall genetic structure was unexpectedly weak for a species distributed among islands. This empirical study shows that extensive gene flow, particularly mediated by seeds, can ameliorate population subdivision resulting from extinction-recolonization dynamics and isolation by distance.

  2. Construction of Core Collections Suitable for Association Mapping to Optimize Use of Mediterranean Olive (Olea europaea L.) Genetic Resources

    PubMed Central

    El Bakkali, Ahmed; Haouane, Hicham; Moukhli, Abdelmajid; Costes, Evelyne; Van Damme, Patrick; Khadari, Bouchaib

    2013-01-01

    Phenotypic characterisation of germplasm collections is a decisive step towards association mapping analyses, but it is particularly expensive and tedious for woody perennial plant species. Characterisation could be more efficient if focused on a reasonably sized subset of accessions, or so-called core collection (CC), reflecting the geographic origin and variability of the germplasm. The questions that arise concern the sample size to use and genetic parameters that should be optimized in a core collection to make it suitable for association mapping. Here we investigated these questions in olive (Olea europaea L.), a perennial fruit species. By testing different sampling methods and sizes in a worldwide olive germplasm bank (OWGB Marrakech, Morocco) containing 502 unique genotypes characterized by nuclear and plastid loci, a two-step sampling method was proposed. The Shannon-Weaver diversity index was found to be the best criterion to be maximized in the first step using the Core Hunter program. A primary core collection of 50 entries (CC50) was defined that captured more than 80% of the diversity. This latter was subsequently used as a kernel with the Mstrat program to capture the remaining diversity. 200 core collections of 94 entries (CC94) were thus built for flexibility in the choice of varieties to be studied. Most entries of both core collections (CC50 and CC94) were revealed to be unrelated due to the low kinship coefficient, whereas a genetic structure spanning the eastern and western/central Mediterranean regions was noted. Linkage disequilibrium was observed in CC94 which was mainly explained by a genetic structure effect as noted for OWGB Marrakech. Since they reflect the geographic origin and diversity of olive germplasm and are of reasonable size, both core collections will be of major interest to develop long-term association studies and thus enhance genomic selection in olive species. PMID:23667437

  3. Construction of core collections suitable for association mapping to optimize use of Mediterranean olive (Olea europaea L.) genetic resources.

    PubMed

    El Bakkali, Ahmed; Haouane, Hicham; Moukhli, Abdelmajid; Costes, Evelyne; Van Damme, Patrick; Khadari, Bouchaib

    2013-01-01

    Phenotypic characterisation of germplasm collections is a decisive step towards association mapping analyses, but it is particularly expensive and tedious for woody perennial plant species. Characterisation could be more efficient if focused on a reasonably sized subset of accessions, or so-called core collection (CC), reflecting the geographic origin and variability of the germplasm. The questions that arise concern the sample size to use and genetic parameters that should be optimized in a core collection to make it suitable for association mapping. Here we investigated these questions in olive (Olea europaea L.), a perennial fruit species. By testing different sampling methods and sizes in a worldwide olive germplasm bank (OWGB Marrakech, Morocco) containing 502 unique genotypes characterized by nuclear and plastid loci, a two-step sampling method was proposed. The Shannon-Weaver diversity index was found to be the best criterion to be maximized in the first step using the Core Hunter program. A primary core collection of 50 entries (CC50) was defined that captured more than 80% of the diversity. This latter was subsequently used as a kernel with the Mstrat program to capture the remaining diversity. 200 core collections of 94 entries (CC94) were thus built for flexibility in the choice of varieties to be studied. Most entries of both core collections (CC50 and CC94) were revealed to be unrelated due to the low kinship coefficient, whereas a genetic structure spanning the eastern and western/central Mediterranean regions was noted. Linkage disequilibrium was observed in CC94 which was mainly explained by a genetic structure effect as noted for OWGB Marrakech. Since they reflect the geographic origin and diversity of olive germplasm and are of reasonable size, both core collections will be of major interest to develop long-term association studies and thus enhance genomic selection in olive species.

  4. Immunoproteomic tools are used to identify masked allergens: Ole e 12, an allergenic isoflavone reductase from olive (Olea europaea) pollen.

    PubMed

    Castro, Lourdes; Crespo, Jesús F; Rodríguez, Julia; Rodríguez, Rosalía; Villalba, Mayte

    2015-12-01

    Proteins performing important biochemical activities in the olive tree (Olea europaea) pollen have been identified as allergens. One novel 37-kDa protein seems to be associated to the IgE-binding profile of a group of patients suffering allergy to peach and olive pollen. Three previously described olive pollen allergens exhibit very similar molecular mass. Our objective was to identify this allergen by using immunoproteomic approaches. After 2D-electrophoresis and mass spectrometry, peptide sequences from several IgE-binding spots, allowed identifying this new allergen, as well as cloning and DNA sequencing of the corresponding gene. The allergen, named Ole e 12, is a polymorphic isoflavone reductase-like protein of 308 amino acids showing 80% and 74% identity with birch and pear allergens, Bet v 6 and Pyr c 5, respectively. A prevalence of 33% in the selected population is in contrast to 4%-10% in groups of subjects suffering from pollinosis. Recombinant allergen was produced in Escherichia coli, and deeply characterised. Immunoblotting and ELISA detection as well as inhibition experiments were performed with polyclonal antisera and allergic patients' sera. The recombinant allergen retains the IgE reactivity of its natural counterpart. Close structural and immunological relationships between members of this protein family were supported by their IgG recognition in vegetable species. In summary, Ole e 12 is a minor olive pollen allergen, which gains relevance in patients allergic to peach with olive pollinosis. Proteomic approaches used to analyse this allergen provide useful tools to identify hidden allergens, relevant for several allergic populations and thus complete allergenic panels.

  5. Assessing ambient ozone injury in olive (Olea europaea L.) plants by using the antioxidant ethylenediurea (EDU) in Saudi Arabia.

    PubMed

    Basahi, J M; Ismail, I M; Haiba, N S; Hassan, I A; Lorenzini, G

    2016-06-01

    The antiozonant chemical, ethylenediurea (N-[2-(2-oxo-1-imidazolidinyl)ethyl]-N'-phenylurea, abbreviated as EDU), was applied as stem injections or soil drenches to 5-year-old containerized plants of olive (Olea europaea L. cultivar Kalamata) in growth chambers in order to assess its ameliorative effects against realistic ozone (O3) stress. Visible injury symptoms were reduced greatly in individuals treated with EDU, with injection applications having greater protection than soil drenches. EDU application caused increases in the measured ecophysiological parameters compared to untreated individuals. In particular, the stem injection protected plants against photosynthetic impairment (unchanged net photosynthetic rates and intercellular CO2 concentration, in comparison to plants grown in filtered air). EDU application increased the protection of PSII from ambient O3 oxidative stress, although it did not retain the proportion of redox state of QA, pigment composition of photosynthetic apparatus and size of light-harvesting complex of PSII. However, the stem injection of plants with EDU induced lower non-photochemical quenching (NPQ) values in comparison to ambient air (-2 %), indicating a better photoprotection of PSII in comparison to soil drench application. EDU application caused increases in the morphological and biometric parameters compared to individuals exposed to ambient air. To the best of our knowledge, this is the first study highlighting the protection of Kalamata olive trees due to EDU in terms of growth, yield, visible injury, and photosynthetic performance. Furthermore, this study proved that EDU could be a low-cost and a low-technology efficient tool for assessing O3 effects on plant performances in the field in Saudi Arabia.

  6. Comparing the historic olive trees (Olea europaea L.) of Santa Cruz with contemporaneous trees in the Santa Barbara, CA area: a case study of diversity and structure in an introduced agricultural species conserved in situ

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Historic populations of crop species outside their centers of origin and diversity, like the domestic olive (Olea europaea L.) in North America, are genetic resources for contemporary agriculture, including genotypes that could be adapted to, local conditions. The primary goal of this study was to d...

  7. Effect of Ganoderma lucidum (Reishi mushroom) or Olea europaea (olive) leaves on oxidative stability of rabbit meat fortified with n-3 fatty acids.

    PubMed

    Trebušak, Tina; Levart, Alenka; Salobir, Janez; Pirman, Tatjana

    2014-03-01

    The objective of the present study was to evaluate the effect of Ganoderma lucidum (Reishi mushroom) or Olea europaea (olive tree) leaves on oxidative stability of rabbit meat fortified with n-3 fatty acids. Forty-eight slovenska kunka (SIKA) rabbits were divided into four homogeneous groups. The control group (CONT-) received diet with 6% palm fat; other groups received diet with 6% linseed oil and were either unsupplemented (CONT+) or supplemented with 1% of G. lucidum (REISHI) or O. europaea leaves (OLIVE). Rabbits were slaughtered and fatty acid composition, concentration of vitamin E and malondialdehyde (MDA) in back muscle were analyzed. The results showed that linseed oil addition improved fatty acid composition by increasing polyunsaturated fatty acid (PUFA) proportion, decreasing proportion of saturated fatty acid (SFA) and reducing n-6/n-3 ratio in rabbit meat. Groups that were supplemented with linseed oil had lower content of α-tocopherol and higher content of γ-tocopherol, compared to the CONT- group. The addition of potential antioxidants did not effectively prevent oxidation of rabbit meat.

  8. Genome-wide identification of alternate bearing-associated microRNAs (miRNAs) in olive (Olea europaea L.)

    PubMed Central

    2013-01-01

    Background Alternate bearing is a widespread phenomenon among crop plants, defined as the tendency of certain fruit trees to produce a high-yield crop one year ("on-year"), followed by a low-yield or even no crop the following year ("off-year"). Several factors may affect the balance between such developmental phase-transition processes. Among them are the microRNA (miRNA), being gene-expression regulators that have been found to be involved as key determinants in several physiological processes. Results Six olive (Olea europaea L. cv. Ayvalik variety) small RNA libraries were constructed from fruits (ripe and unripe) and leaves (”on year” and ”off year” leaves in July and in November, respectively) and sequenced by high-throughput Illumina sequencing. The RNA was retrotranscribed and sequenced using the high-throughput Illumina platform. Bioinformatics analyses of 93,526,915 reads identified 135 conserved miRNA, belonging to 22 miRNA families in the olive. In addition, 38 putative novel miRNAs were discovered in the datasets. Expression of olive tree miRNAs varied greatly among the six libraries, indicating the contribution of diverse miRNA in balancing between reproductive and vegetative phases. Predicted targets of miRNA were categorized into 108 process ontology groups with significance abundance. Among those, potential alternate bearing-associated processes were found, such as development, hormone-mediated signaling and organ morphogenesis. The KEGG analyses revealed that the miRNA-targeted genes are involved in seven main pathways, belonging to carbohydrate metabolism and hormone signal-transduction pathways. Conclusion A comprehensive study on olive miRNA related to alternate bearing was performed. Regulation of miRNA under different developmental phases and tissues indicated that control of nutrition and hormone, together with flowering processes had a noteworthy impact on the olive tree alternate bearing. Our results also provide significant data

  9. Partial Root-Zone Drying of Olive (Olea europaea var. 'Chetoui') Induces Reduced Yield under Field Conditions.

    PubMed

    Dbara, Soumaya; Haworth, Matthew; Emiliani, Giovani; Ben Mimoun, Mehdi; Gómez-Cadenas, Aurelio; Centritto, Mauro

    2016-01-01

    The productivity of olive trees in arid and semi-arid environments is closely linked to irrigation. It is necessary to improve the efficiency of irrigation techniques to optimise the amount of olive fruit produced in relation to the volume of water used. Partial root-zone drying (PRD) is a water saving irrigation technique that theoretically allows the production of a root-to-shoot signal that modifies the physiology of the above-ground parts of the plant; specifically reducing stomatal conductance (gs) and improving water use efficiency (WUE). Partial root-zone drying has been successfully applied under field conditions to woody and non-woody crops; yet the few previous trials with olive trees have produced contrasting results. Thirty year-old olive trees (Olea europaea 'var. Chetoui') in a Tunisian grove were exposed to four treatments from May to October for three-years: 'control' plants received 100% of the potential evapotranspirative demand (ETc) applied to the whole root-zone; 'PRD100' were supplied with an identical volume of water to the control plants alternated between halves of the root-zone every ten-days; 'PRD50' were given 50% of ETc to half of the root-system, and; 'rain-fed' plants received no supplementary irrigation. Allowing part of the root-zone to dry resulted in reduced vegetative growth and lower yield: PRD100 decreased yield by ~47% during productive years. During the less productive years of the alternate bearing cycle, irrigation had no effect on yield; this suggests that withholding of water during 'off-years' may enhance the effectiveness of irrigation over a two-year cycle. The amount and quality of oil within the olive fruit was unaffected by the irrigation treatment. Photosynthesis declined in the PRD50 and rain-fed trees due to greater diffusive limitations and reduced biochemical uptake of CO2. Stomatal conductance and the foliar concentration of abscisic acid (ABA) were not altered by PRD100 irrigation, which may indicate the

  10. A sensitive liquid chromatography-mass spectrometry method for the simultaneous determination in plasma of pentacyclic triterpenes of Olea europaea L.

    PubMed

    Giménez, Estela; Juan, M Emília; Calvo-Melià, Sara; Planas, Joana M

    2017-08-15

    Table olives are especially rich in pentacyclic triterpenic compounds, which exert several biological activities. A crucial step in order to know if these compounds could contribute to the beneficial and healthy properties of this food is their measurement in blood. Therefore, the present study describes a simple and accurate liquid-liquid extraction followed by LC-QqQ-MS analysis for the simultaneous determination of the main pentacyclic triterpenes from Olea europaea L. in rat plasma. The method was validated by the analysis of blank plasma samples spiked with pure compounds, obtaining a linear correlation, adequate sensitivity with a limit of quantification ranging from 1nM for maslinic acid to 10nM for uvaol. Precision and accuracy were lower than 10% in all cases and recoveries were between 95 and 104%. The oral administration of olives to rats and its determination in plasma verified that the established methodology is appropriate for bioavailability studies.

  11. Complete genome sequence of Pseudomonas fluorescens strain PICF7, an indigenous root endophyte from olive (Olea europaea L.) and effective biocontrol agent against Verticillium dahliae

    PubMed Central

    2015-01-01

    Pseudomonas fluorescens strain PICF7 is a native endophyte of olive roots. Previous studies have shown this motile, Gram-negative, non-sporulating bacterium is an effective biocontrol agent against the soil-borne fungus Verticillium dahliae, the causal agent of one of the most devastating diseases for olive (Olea europaea L.) cultivation. Here, we announce and describe the complete genome sequence of Pseudomonas fluorescens strain PICF7 consisting of a circular chromosome of 6,136,735 bp that encodes 5,567 protein-coding genes and 88 RNA-only encoding genes. Genome analysis revealed genes predicting factors such as secretion systems, siderophores, detoxifying compounds or volatile components. Further analysis of the genome sequence of PICF7 will help in gaining insights into biocontrol and endophytism. PMID:25685259

  12. The efficacy of kaolin particle film on oil quality indices of olive trees (Olea europaea L.) cv 'Zard' grown under warm and semi-arid region of Iran.

    PubMed

    Khaleghi, Esmaeil; Arzani, Kazem; Moallemi, Norollah; Barzegar, Mohsen

    2015-01-01

    Kaolin particle film (0%, 3% and 6%; w/v), as an antitranspirant treatment, was applied to mature 'Zard' olive trees (Olea europaea L.). Olive oil was extracted from harvested fruit and fatty acid composition and other oil quality indices of the fruit assessed over crop seasons. Kaolin increased chlorophyll and carotenoid contents, but decreased peroxide and iodine values, and UV absorbance extinction coefficients, of the oil. The highest palmitic acid was observed in the oil obtained from untreated trees (17%). Kaolin increased oleic acid up to 65% and 64% in the first and second crop seasons, respectively, but decreased linoleic and linolenic acid contents. Monounsaturated acids (65%) and oleic acid/linoleic acid ratios (4) were higher in oil obtained from kaolin treated than untreated trees. Therefore it can be expected that extracted olive oil from kaolin treated trees has a higher oxidative stability and shelf life than untreated trees.

  13. Factors affecting the contents of iridoid oleuropein in olive leaves (Olea europaea L.).

    PubMed

    Ranalli, Alfonso; Contento, Stefania; Lucera, Lucia; Di Febo, Moira; Marchegiani, Donato; Di Fonzo, Vittoria

    2006-01-25

    In this study, for the first time, the impact of the genetic factor on the contents of oleuropein in olive leaves was not only evaluated but the influence exerted by the color/age of leaves (green, green-yellowish, and yellow) and the collecting period (spring or autumn) was also evaluated. A repetitive high-resolution gas chromatographic quantitation method and an accurate high-performance liquid chromatographic method were developed. These analytical methods gave results showing a highly linear relationship. Samples of olive leaves were taken from seven major Italian olive cultivars, such as Dritta, Leccino, Caroleo, Coratina, Castiglionese, Nebbio, and Grossa di Cassano. Such a vegetal raw material could actually be exploited for recovering oleuropein, considered to be a high-added value molecule. This could be converted into hydrxytyrosol, a compound known to possess strong bioactive properties. Olive leaves showed considerable contents of oleuropein, which with some cultivars were even higher with respect to those present in the corresponding olive fruits (reported in the literature). The amounts of oleuropein in the collected leaves were markedly modified by the color/age and genetic factors, whereas meaningless variations were ascribable to the quantitation method and the collecting period factors. Various chemometrics, applied to the obtained analytical data, appeared to be effective in discriminating the samples on the basis of the above-examined experimental factors, thus confirming how these should be taken into account in future industrial recovery of oleuropein from olive leaves.

  14. LTR retrotransposon dynamics in the evolution of the olive (Olea europaea) genome.

    PubMed

    Barghini, Elena; Natali, Lucia; Giordani, Tommaso; Cossu, Rosa Maria; Scalabrin, Simone; Cattonaro, Federica; Šimková, Hana; Vrána, Jan; Doležel, Jaroslav; Morgante, Michele; Cavallini, Andrea

    2015-02-01

    Improved knowledge of genome composition, especially of its repetitive component, generates important information for both theoretical and applied research. The olive repetitive component is made up of two main classes of sequences: tandem repeats and retrotransposons (REs). In this study, we provide characterization of a sample of 254 unique full-length long terminal repeat (LTR) REs. In the sample, Ty1-Copia elements were more numerous than Ty3-Gypsy elements. Mapping a large set of Illumina whole-genome shotgun reads onto the identified retroelement set revealed that Gypsy elements are more redundant than Copia elements. The insertion time of intact retroelements was estimated based on sister LTR's divergence. Although some elements inserted relatively recently, the mean insertion age of the isolated retroelements is around 18 million yrs. Gypsy and Copia retroelements showed different waves of transposition, with Gypsy elements especially active between 10 and 25 million yrs ago and nearly inactive in the last 7 million yrs. The occurrence of numerous solo-LTRs related to isolated full-length retroelements was ascertained for two Gypsy elements and one Copia element. Overall, the results reported in this study show that RE activity (both retrotransposition and DNA loss) has impacted the olive genome structure in more ancient times than in other angiosperms.

  15. Novel qPCR systems for olive (Olea europaea L.) authentication in oils and food.

    PubMed

    Ramos-Gómez, Sonia; Busto, María D; Albillos, Silvia M; Ortega, Natividad

    2016-03-01

    The traceability of olive oil is an unresolved issue that remains a challenge. In this field, DNA-based techniques are very powerful tools for discrimination that are less negatively influenced by environmental conditions than other techniques. More specifically, quantitative real time PCR (qPCR) achieves a high degree of sensitivity, although the DNA that it can directly isolate from these oils presents drawbacks. Our study reports the analysis of eight systems, in order to determine their suitability for olive detection in oil and oil-derived foodstuffs. The eight systems were analyzed on the basis of their sensitivity and specificity in the qPCR assay, their relative sensitivity to olive DNA detection and DNA mixtures, their sensitivity and specificity to olive in vegetable oils and the detection of olive in commercial products. The results show that the PetN-PsbM system, designed in this study, is a suitable and reliable technique in relation to olive oil and olive ingredients in both food authentication and food safety processes.

  16. De Novo Assembly and Functional Annotation of the Olive (Olea europaea) Transcriptome

    PubMed Central

    Muñoz-Mérida, Antonio; González-Plaza, Juan José; Cañada, Andrés; Blanco, Ana María; García-López, Maria del Carmen; Rodríguez, José Manuel; Pedrola, Laia; Sicardo, M. Dolores; Hernández, M. Luisa; De la Rosa, Raúl; Belaj, Angjelina; Gil-Borja, Mayte; Luque, Francisco; Martínez-Rivas, José Manuel; Pisano, David G.; Trelles, Oswaldo; Valpuesta, Victoriano; Beuzón, Carmen R.

    2013-01-01

    Olive breeding programmes are focused on selecting for traits as short juvenile period, plant architecture suited for mechanical harvest, or oil characteristics, including fatty acid composition, phenolic, and volatile compounds to suit new markets. Understanding the molecular basis of these characteristics and improving the efficiency of such breeding programmes require the development of genomic information and tools. However, despite its economic relevance, genomic information on olive or closely related species is still scarce. We have applied Sanger and 454 pyrosequencing technologies to generate close to 2 million reads from 12 cDNA libraries obtained from the Picual, Arbequina, and Lechin de Sevilla cultivars and seedlings from a segregating progeny of a Picual × Arbequina cross. The libraries include fruit mesocarp and seeds at three relevant developmental stages, young stems and leaves, active juvenile and adult buds as well as dormant buds, and juvenile and adult roots. The reads were assembled by library or tissue and then assembled together into 81 020 unigenes with an average size of 496 bases. Here, we report their assembly and their functional annotation. PMID:23297299

  17. The expression of light-related leaf functional traits depends on the location of individual leaves within the crown of isolated Olea europaea trees

    PubMed Central

    Escribano-Rocafort, Adrián G.; Ventre-Lespiaucq, Agustina B.; Granado-Yela, Carlos; Rubio de Casas, Rafael; Delgado, Juan A.; Balaguer, Luis

    2016-01-01

    Background The spatial arrangement and expression of foliar syndromes within tree crowns can reflect the coupling between crown form and function in a given environment. Isolated trees subjected to high irradiance and concomitant stress may adjust leaf phenotypes to cope with environmental gradients that are heterogeneous in space and time within the tree crown. The distinct expression of leaf phenotypes among crown positions could lead to complementary patterns in light interception at the crown scale. Methods We quantified eight light-related leaf traits across 12 crown positions of ten isolated Olea europaea trees in the field. Specifically, we investigated whether the phenotypic expression of foliar traits differed among crown sectors and layers and five periods of the day from sunrise to sunset. We investigated the consequences in terms of the exposed area of the leaves at the tree scale during a single day. Key Results All traits differed among crown positions except the length-to-width ratio of the leaves. We found a strong complementarity in the patterns of the potential exposed area of the leaves among day periods as a result of a non-random distribution of leaf angles across the crown. Leaf exposure at the outer layer was below 60 % of the displayed surface, reaching maximum interception during morning periods. Daily interception increased towards the inner layer, achieving consecutive maximization from east to west positions within the crown, matching the sun’s trajectory. Conclusions The expression of leaf traits within isolated trees of O. europaea varies continuously through the crown in a gradient of leaf morphotypes and leaf angles depending on the exposure and location of individual leaves. The distribution of light-related traits within the crown and the complementarity in the potential exposure patterns of the leaves during the day challenges the assumption of low trait variability within individuals. PMID:26944783

  18. Partial Root-Zone Drying of Olive (Olea europaea var. 'Chetoui') Induces Reduced Yield under Field Conditions

    PubMed Central

    Dbara, Soumaya; Haworth, Matthew; Emiliani, Giovani; Ben Mimoun, Mehdi; Gómez-Cadenas, Aurelio; Centritto, Mauro

    2016-01-01

    The productivity of olive trees in arid and semi-arid environments is closely linked to irrigation. It is necessary to improve the efficiency of irrigation techniques to optimise the amount of olive fruit produced in relation to the volume of water used. Partial root-zone drying (PRD) is a water saving irrigation technique that theoretically allows the production of a root-to-shoot signal that modifies the physiology of the above-ground parts of the plant; specifically reducing stomatal conductance (gs) and improving water use efficiency (WUE). Partial root-zone drying has been successfully applied under field conditions to woody and non-woody crops; yet the few previous trials with olive trees have produced contrasting results. Thirty year-old olive trees (Olea europaea ‘var. Chetoui’) in a Tunisian grove were exposed to four treatments from May to October for three-years: ‘control’ plants received 100% of the potential evapotranspirative demand (ETc) applied to the whole root-zone; ‘PRD100’ were supplied with an identical volume of water to the control plants alternated between halves of the root-zone every ten-days; ‘PRD50’ were given 50% of ETc to half of the root-system, and; ‘rain-fed’ plants received no supplementary irrigation. Allowing part of the root-zone to dry resulted in reduced vegetative growth and lower yield: PRD100 decreased yield by ~47% during productive years. During the less productive years of the alternate bearing cycle, irrigation had no effect on yield; this suggests that withholding of water during ‘off-years’ may enhance the effectiveness of irrigation over a two-year cycle. The amount and quality of oil within the olive fruit was unaffected by the irrigation treatment. Photosynthesis declined in the PRD50 and rain-fed trees due to greater diffusive limitations and reduced biochemical uptake of CO2. Stomatal conductance and the foliar concentration of abscisic acid (ABA) were not altered by PRD100 irrigation

  19. A De novo Transcriptomic Approach to Identify Flavonoids and Anthocyanins “Switch-Off” in Olive (Olea europaea L.) Drupes at Different Stages of Maturation

    PubMed Central

    Iaria, Domenico L.; Chiappetta, Adriana; Muzzalupo, Innocenzo

    2016-01-01

    Highlights A de novo transcriptome reconstruction of olive drupes was performed in two genotypesGene expression was monitored during drupe development in two olive cultivarsTranscripts involved in flavonoid and anthocyanin pathways were analyzed in Cassanese and Leucocarpa cultivarsBoth cultivar and developmental stage impact gene expression in Olea europaea fruits. During ripening, the fruits of the olive tree (Olea europaea L.) undergo a progressive chromatic change characterized by the formation of a red-brown “spot” which gradually extends on the epidermis and in the innermost part of the mesocarp. This event finds an exception in the Leucocarpa cultivar, in which we observe a destabilized equilibrium between the metabolisms of chlorophyll and other pigments, particularly the anthocyanins whose switch-off during maturation promotes the white coloration of fruits. Despite its importance, genomic information on the olive tree is still lacking. Different RNA-seq libraries were generated from drupes of “Leucocarpa” and “Cassanese” olive genotypes, sampled at 100 and 130 days after flowering (DAF), and were used in order to identify transcripts involved in the main phenotypic changes of fruits during maturation and their corresponding expression patterns. A total of 103,359 transcripts were obtained and 3792 and 3064 were differentially expressed in “Leucocarpa” and “Cassanese” genotypes, respectively, during 100–130 DAF transition. Among them flavonoid and anthocyanin related transcripts such as phenylalanine ammonia lyase (PAL), cinnamate 4-hydroxylase (C4H), 4-coumarate-CoA ligase (4CL), chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), flavonol 3′-hydrogenase (F3′H), flavonol 3′5 ′-hydrogenase (F3′5′H), flavonol synthase (FLS), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase (ANS), UDP-glucose:anthocianidin: flavonoid glucosyltransferase (UFGT) were identified. These results contribute

  20. Olea europaea leaf (Ph.Eur.) extract as well as several of its isolated phenolics inhibit the gout-related enzyme xanthine oxidase.

    PubMed

    Flemmig, J; Kuchta, K; Arnhold, J; Rauwald, H W

    2011-05-15

    In Mediterranean folk medicine Olea europaea L. leaf (Ph.Eur.) preparations are used as a common remedy for gout. In this in vitro study kinetic measurements were performed on both an 80% ethanolic (v/v) Olea europaea leaf dry extract (OLE) as well as on nine of its typical phenolic constituents in order to investigate its possible inhibitory effects on xanthine oxidase (XO), an enzyme well known to contribute significantly to this pathological process. Dixon and Lineweaver-Burk plot analysis were used to determine K(i) values and the inhibition mode for the isolated phenolics, which were analysed by RP-HPLC for standardisation of OLE. The standardised OLE as well as some of the tested phenolics significantly inhibited the activity of XO. Among these, the flavone aglycone apigenin exhibited by far the strongest effect on XO with a K(i) value of 0.52 μM. In comparison, the known synthetic XO inhibitor allopurinol, used as a reference standard, showed a K(i) of 7.3 μM. Although the phenolic secoiridoid oleuropein, the main ingredient of the extract (24.8%), had a considerable higher K(i) value of 53.0 μM, it still displayed a significant inhibition of XO. Furthermore, caffeic acid (K(i) of 11.5 μM; 1.89% of the extract), luteolin-7-O-β-D-glucoside (K(i) of 15.0 μM; 0.86%) and luteolin (K(i) of 2.9 μM; 0.086%) also contributed significantly to the XO inhibiting effect of OLE. For oleuropein, a competitive mode of inhibition was found, while all other active substances displayed a mixed mode of inhibition. Tyrosol, hydroxytyrosol, verbascoside, and apigenin-7-O-β-D-glucoside, which makes up for 0.3% of the extract, were inactive in all tested concentrations. Regarding the pharmacological in vitro effect of apigenin-7-O-β-D-glucoside, it has to be considered that it is transformed into the active apigenin aglycone in the mammalian body, thus also contributing substantially to the anti-gout activity of olive leaves. For the first time, this study provides a

  1. Correlation between airborne Olea europaea pollen concentrations and levels of the major allergen Ole e 1 in Córdoba, Spain, 2012-2014

    NASA Astrophysics Data System (ADS)

    Plaza, M. P.; Alcázar, P.; Galán, C.

    2016-12-01

    Olea europaea L. pollen is the second-largest cause of pollinosis in the southern Iberian Peninsula. Airborne-pollen monitoring networks provide essential data on pollen dynamics over a given study area. Recent research, however, has shown that airborne pollen levels alone do not always provide a clear indicator of actual exposure to aeroallergens. This study sought to evaluate correlations between airborne concentrations of olive pollen and Ole e 1 allergen levels in Córdoba (southern Spain), in order to determine whether atmospheric pollen concentrations alone are sufficient to chart changes in hay fever symptoms. The influence of major weather-related variables on local airborne pollen and allergen levels was also examined. Monitoring was carried out from 2012 to 2014. Pollen sampling was performed using a Hirst-type sampler, following the protocol recommended by the Spanish Aerobiology Network. A multi-vial cyclone sampler was used to collect aeroallergens, and allergenic particles were quantified by ELISA assay. Significant positive correlations were found between daily airborne allergen levels and atmospheric pollen concentrations, although there were occasions when allergen was detected before and after the pollen season and in the absence of airborne pollen. The correlation between the two was irregular, and pollen potency displayed year-on-year variations and did not necessarily match pollen-season-intensity.

  2. Polyphenol oxidase and its relationship with oleuropein concentration in fruits and leaves of olive (Olea europaea) cv. 'Picual' trees during fruit ripening.

    PubMed

    Ortega-García, Francisca; Blanco, Santos; Peinado, M Angeles; Peragón, Juan

    2008-01-01

    Oleuropein, the main phenolic compound of olive fruit, has important antioxidant properties that are responsible for some of the nutritional properties of fruits and the defence mechanism of leaves. Polyphenol oxidase (PPO) activity changes during fruit ripening in many plants. We studied the kinetics and molecular properties of PPO in fruits and leaves of olive (Olea europaea L.) cv. 'Picual' trees and the relationship between PPO and oleuropein concentration during fruit ripening. Polyphenol oxidase showed hyperbolic kinetics in fruits and leaves. Significant increases in PPO specific activity, V(max), K(m )and catalytic efficiency occurred during fruit ripening. Based on SDS-PAGE under partially denaturing conditions and in-gel staining with DL-3,4-dihydroxyphenylalanine, PPO activity was found in one major protein of 55 and 50 kDA in fruits and leaves, respectively. During the last stages of fruit maturation, a second 36 kDa protein was observed in fruits but not in leaves, indicating that this protein could serve as a marker of the final phase of fruit maturation. Under fully denaturing conditions, only one 27.7 kDa immunoreactive band was detected in fruits. Both the amount of PPO activity and the amount of PPO protein increased significantly during fruit maturation. Immunohistochemical studies indicated that PPO is located in the epidermis, parenchyma and companion vascular cells of leaves as well as in the epidermis of fruit. During fruit maturation, oleuropein concentration measured by HPLC significantly decreased in fruits and increased in leaves.

  3. Impact of proline application on cadmium accumulation, mineral nutrition and enzymatic antioxidant defense system of Olea europaea L. cv Chemlali exposed to cadmium stress.

    PubMed

    Zouari, Mohamed; Ben Ahmed, Chedlia; Elloumi, Nada; Bellassoued, Khaled; Delmail, David; Labrousse, Pascal; Ben Abdallah, Ferjani; Ben Rouina, Bechir

    2016-06-01

    Proline plays an important role in plant response to various environmental stresses. However, its involvement in mitigation of heavy metal stress in plants remains elusive. In this study, we examined the effectiveness of exogenous proline (10 and 20 mM) in alleviating cadmium induced inhibitory effects in young olive plants (Olea europaea L. cv. Chemlali) exposed to two Cd levels (10 and 30 mg CdCl2 kg(-1) soil). The Cd treatment induced substantial accumulation of Cd in both root and leaf tissues and a decrease in gas exchange, photosynthetic pigments contents, uptake of essential elements (Ca, Mg and K) and plant biomass. Furthermore, an elevation of antioxidant enzymes activities (superoxide dismutase, catalase, glutathione peroxydase) and proline content in association with relatively high amounts of hydrogen peroxide, thiobarbituric acid reactive substances and electrolyte leakage were observed. Interestingly, the application of exogenous proline alleviated the oxidative damage induced by Cd accumulation. In fact, Cd-stressed olive plants treated with proline showed an increase of antioxidant enzymes activities, photosynthetic activity, nutritional status, plant growth and oil content of olive fruit. Generally, it seems that proline supplementation alleviated the deleterious effects of young olive plants exposed to Cd stress.

  4. Thermal stability of oils added with avocado (Persea americana cv. Hass) or olive (Olea europaea cv. Arbequina) leaf extracts during the French potatoes frying.

    PubMed

    Jiménez, Paula; García, Paula; Bustamante, Andrés; Barriga, Andrés; Robert, Paz

    2017-04-15

    Effect of the addition of avocado (Persea americana cv. Hass) or olive (Olea europaea cv. Arbequina) hydroalcoholic leaf extracts (AHE and OHE, respectively) on thermal stability of canola oil (CO) and high oleic sunflower oil (HOSO) during French potatoes frying at 180°C was studied. The extracts were characterized by the total phenolic content, phenol chromatographic profiles and antioxidant activity. B-type trimer procyanidins were the major phenolic compounds identified in AHE. OHE showed higher phenol content, antioxidant activity regarding AHE. CO+OHE and HOSO+OHE decreased the formation of polar compounds and showed an anti-polymeric effect with respect to oils without extracts, whereas AHE extract showed a prooxidant effect on HOSO. Therefore, OHE showed an antioxidant effect on HOSO and CO under the studied conditions. In addition, all systems (CO+AHE, HOSO+AHE, CO+OHE and HOSO+OHE) increased the retention of tocopherols. These results demonstrate the potential utility of OHE as natural antioxidant for oils.

  5. Variability of virgin olive oil phenolic compounds in a segregating progeny from a single cross in Olea europaea L. and sensory and nutritional quality implications.

    PubMed

    Pérez, Ana G; León, Lorenzo; Pascual, Mar; Romero-Segura, Carmen; Sánchez-Ortiz, Araceli; de la Rosa, Raúl; Sanz, Carlos

    2014-01-01

    Virgin olive oil phenolic compounds are responsible for its nutritional and sensory quality. The synthesis of phenolic compounds occurs when enzymes and substrates meet as olive fruit is crushed during the industrial process to obtain the oil. The genetic variability of the major phenolic compounds of virgin olive oil was studied in a progeny of the cross of Picual x Arbequina olive cultivars (Olea europaea L.). They belong to four different groups: compounds that included tyrosol or hydroxytyrosol in their molecules, lignans, flavonoids, and phenolic acids. Data of phenolics in the oils showed that the progeny displayed a large degree of variability, widely transgressing the genitor levels. This high variability can be of interest on breeding programs. Thus, multivariate analysis allowed to identify genotypes within the progeny particularly interesting in terms of phenolic composition and deduced organoleptic and nutritional quality. The present study has demonstrated that it is possible to obtain enough degree of variability with a single cross of olive cultivars for compounds related to the nutritional and organoleptic properties of virgin olive oil.

  6. Evaluation of RNA extraction methods and identification of putative reference genes for real-time quantitative polymerase chain reaction expression studies on olive (Olea europaea L.) fruits.

    PubMed

    Nonis, Alberto; Vezzaro, Alice; Ruperti, Benedetto

    2012-07-11

    Genome wide transcriptomic surveys together with targeted molecular studies are uncovering an ever increasing number of differentially expressed genes in relation to agriculturally relevant processes in olive (Olea europaea L). These data need to be supported by quantitative approaches enabling the precise estimation of transcript abundance. qPCR being the most widely adopted technique for mRNA quantification, preliminary work needs to be done to set up robust methods for extraction of fully functional RNA and for the identification of the best reference genes to obtain reliable quantification of transcripts. In this work, we have assessed different methods for their suitability for RNA extraction from olive fruits and leaves and we have evaluated thirteen potential candidate reference genes on 21 RNA samples belonging to fruit developmental/ripening series and to leaves subjected to wounding. By using two different algorithms, GAPDH2 and PP2A1 were identified as the best reference genes for olive fruit development and ripening, and their effectiveness for normalization of expression of two ripening marker genes was demonstrated.

  7. Endophytic colonization and biocontrol performance of Pseudomonas fluorescens PICF7 in olive (Olea europaea L.) are determined neither by pyoverdine production nor swimming motility.

    PubMed

    Maldonado-González, M Mercedes; Schilirò, Elisabetta; Prieto, Pilar; Mercado-Blanco, Jesús

    2015-09-01

    Pseudomonas fluorescens PICF7 is an indigenous inhabitant of olive (Olea europaea L.) rhizosphere, able to display endophytic lifestyle in roots, to induce a wide range of defence responses upon colonization of this organ and to exert effective biological control against Verticillium wilt of olive (VWO) (Verticillium dahliae). We aimed to evaluate the involvement of specific PICF7 phenotypes in olive root colonization and VWO biocontrol effectiveness by generating mutants impaired in swimming motility (fliI) or siderophore pyoverdine production (pvdI). Besides, the performance of mutants with diminished in vitro growth in potato dextrose agar medium (gltA) and cysteine (Cys) auxotrophy was also assessed. Results showed that olive root colonization and VWO biocontrol ability of the fliI, pvdI and gltA mutants did not significantly differ from that displayed by the parental strain PICF7. Consequently, altered in vitro growth, swimming motility and pyoverdine production contribute neither to PICF7 VWO suppressive effect nor to its colonization ability. In contrast, the Cys auxotroph mutant showed reduced olive root colonization capacity and lost full biocontrol efficacy. Moreover, confocal laser scanning microscopy revealed that all mutants tested were able to endophytically colonize root tissue to the same extent as wild-type PICF7, discarding these traits as relevant for its endophytic lifestyle.

  8. Identification of leaf volatiles from olive (Olea europaea) and their possible role in the ovipositional preferences of olive fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae).

    PubMed

    Malheiro, Ricardo; Casal, Susana; Cunha, Sara C; Baptista, Paula; Pereira, José Alberto

    2016-01-01

    The olive fly, Bactrocera oleae (Rossi), is a monophagous pest that displays an oviposition preference among cultivars of olive (Olea europaea L.). To clarify the oviposition preference, the olive leaf volatiles of three olive cultivars (Cobrançosa, Madural and Verdeal Transmontana) were assessed by headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) at six different periods of olive fruit maturation and degrees of infestation. A total of 39 volatiles were identified, mainly esters and alcohols, with a minor percentage of aldehydes, ketones and terpenic compounds, including sesquiterpenes. At sampling dates with higher degrees of infestation, cv. Cobrançosa had, simultaneously, significantly lower infestation degrees and higher volatile amounts than the other two cultivars, with a probable deterrent effect for oviposition. The green leaf volatiles (GLVs) (Z)-3-hexen-1-ol and (Z)-3-hexen-1-ol acetate) were the main compounds identified in all cultivars, together with toluene. The abundance of GLVs decreased significantly throughout maturation, without significant differences among cultivars, while toluene showed a general increase and positive correlation with olive fly infestation levels. The results obtained could broaden our understanding of the roles of various types and amounts of olive volatiles in the environment, especially in olive fly host selection and cultivar preference.

  9. Identification of novel virulence genes and metabolic pathways required for full fitness of Pseudomonas savastanoi pv. savastanoi in olive (Olea europaea) knots.

    PubMed

    Matas, Isabel M; Lambertsen, Lotte; Rodríguez-Moreno, Luis; Ramos, Cayo

    2012-12-01

    Comparative genomics and functional analysis of Pseudomonas syringae and related pathogens have mainly focused on diseases of herbaceous plants; however, there is a general lack of knowledge about the virulence and pathogenicity determinants required for infection of woody plants. Here, we applied signature-tagged mutagenesis (STM) to Pseudomonas savastanoi pv. savastanoi during colonization of olive (Olea europaea) knots, with the goal of identifying the range of genes linked to growth and symptom production in its plant host. A total of 58 different genes were identified, and most mutations resulted in hypovirulence in woody olive plants. Sequence analysis of STM mutations allowed us to identify metabolic pathways required for full fitness of P. savastanoi in olive and revealed novel mechanisms involved in the virulence of this pathogen, some of which are essential for full colonization of olive knots by the pathogen and for the lysis of host cells. This first application of STM to a P. syringae-like pathogen provides confirmation of functional capabilities long believed to play a role in the survival and virulence of this group of pathogens but not adequately tested before, and unravels novel factors not correlated previously with the virulence of other plant or animal bacterial pathogens.

  10. Variability of Virgin Olive Oil Phenolic Compounds in a Segregating Progeny from a Single Cross in Olea europaea L. and Sensory and Nutritional Quality Implications

    PubMed Central

    Pérez, Ana G.; León, Lorenzo; Pascual, Mar; Romero-Segura, Carmen; Sánchez-Ortiz, Araceli; de la Rosa, Raúl; Sanz, Carlos

    2014-01-01

    Virgin olive oil phenolic compounds are responsible for its nutritional and sensory quality. The synthesis of phenolic compounds occurs when enzymes and substrates meet as olive fruit is crushed during the industrial process to obtain the oil. The genetic variability of the major phenolic compounds of virgin olive oil was studied in a progeny of the cross of Picual x Arbequina olive cultivars (Olea europaea L.). They belong to four different groups: compounds that included tyrosol or hydroxytyrosol in their molecules, lignans, flavonoids, and phenolic acids. Data of phenolics in the oils showed that the progeny displayed a large degree of variability, widely transgressing the genitor levels. This high variability can be of interest on breeding programs. Thus, multivariate analysis allowed to identify genotypes within the progeny particularly interesting in terms of phenolic composition and deduced organoleptic and nutritional quality. The present study has demonstrated that it is possible to obtain enough degree of variability with a single cross of olive cultivars for compounds related to the nutritional and organoleptic properties of virgin olive oil. PMID:24651694

  11. Control mechanisms operating for lipid biosynthesis differ in oil-palm (Elaeis guineensis Jacq.) and olive (Olea europaea L.) callus cultures.

    PubMed Central

    Ramli, Umi S; Baker, Darren S; Quant, Patti A; Harwood, John L

    2002-01-01

    As a prelude to detailed flux control analysis of lipid synthesis in plants, we have examined the latter in tissue cultures from two important oil crops, olive (Olea europaea L.) and oil palm (Elaeis guineensis Jacq.). Temperature was used to manipulate the overall rate of lipid formation in order to characterize and validate the system to be used for analysis. With [1-14C]acetate as a precursor, an increase in temperature from 20 to 30 degrees C produced nearly a doubling of total lipid labelling. This increase in total lipids did not change the radioactivity in the intermediate acyl-(acyl carrier protein) or acyl-CoA pools, indicating that metabolism of these pools did not exert any significant constraint for overall synthesis. In contrast, there were some differences in the proportional labelling of fatty acids and of lipid classes at the two temperatures. The higher temperature caused a decrease in polyunsaturated fatty acid labelling and an increase in the proportion of triacylglycerol labelling in both calli. The intermediate diacylglycerol was increased in olive, but not in oil palm. Overall the data indicate the suitability of olive and oil-palm cultures for the study of lipid synthesis and indicate that de novo fatty acid synthesis may exert more flux control than complex lipid assembly. In olive, diacylglycerol acyltransferase may exert significant flux control when lipid synthesis is rapid. PMID:12023881

  12. Nitrification Enhancement through pH Control with Rotating Biological Contractors,

    DTIC Science & Technology

    1982-04-01

    Engel, M. S. and Alexander, M., " Growth and Autotrophic Metabolism of Nitrosomonas Europaea ," Jour. Bact.,76, 1958, pp. 217-222. 27. Buswell, A. M...Painter, H. A., "The Influence of Metal Ion Concentrations and pH Value on the Growth of a Nitrosomonas Strain Isolated from Activated Sludge," Jour. Gen...et al., "Laboratory Studies on the Kinetics of the Growth of Nitrosomonas with Relation to the Nitrification Phase of the BOD Test, Appl. Microb., 2

  13. Assessing Animal Welfare Impacts in the Management of European Rabbits (Oryctolagus cuniculus), European Moles (Talpa europaea) and Carrion Crows (Corvus corone)

    PubMed Central

    Baker, Sandra E.; Sharp, Trudy M.; Macdonald, David W.

    2016-01-01

    Human-wildlife conflict is a global issue. Attempts to manage this conflict impact upon wild animal welfare, an issue receiving little attention until relatively recently. Where human activities harm animal welfare these effects should be minimised where possible. However, little is known about the welfare impacts of different wildlife management interventions, and opinions on impacts vary widely. Welfare impacts therefore need to be assessed objectively. Our objectives were to: 1) establish whether an existing welfare assessment model could differentiate and rank the impacts of different wildlife management interventions (for decision-making purposes); 2) identify and evaluate any additional benefits of making formal welfare assessments; and 3) illustrate issues raised by application of the model. We applied the welfare assessment model to interventions commonly used with rabbits (Oryctolagus cuniculus), moles (Talpa europaea) and crows (Corvus corone) in the UK. The model ranked interventions for rabbits (least impact first: fencing, head shot, chest shot) and crows (shooting, scaring, live trapping with cervical dislocation). For moles, managing molehills and tunnels scored least impact. Both spring trapping, and live trapping followed by translocation, scored greater impacts, but these could not be compared directly as they scored on different axes of the model. Some rankings appeared counter-intuitive, highlighting the need for objective formal welfare assessments. As well as ranking the humaneness of interventions, the model highlighted future research needs and how Standard Operating Procedures might be improved. The model is a milestone in assessing wildlife management welfare impacts, but our research revealed some limitations of the model and we discuss likely challenges in resolving these. In future, the model might be developed to improve its utility, e.g. by refining the time-scales. It might also be used to reach consensus among stakeholders about

  14. The perennial pattern of clinical symptoms in children monosensitized to Olea europaea pollen allergens in comparison with subjects with Parietaria and Gramineae pollinosis.

    PubMed

    Liccardi, G; Russo, M; Piccolo, A; Lobefalo, G; Salzillo, A; D'Amato, M; D'Amato, G

    1997-01-01

    Because the pediatric age represents a good model to study the correlation between the exposure to allergens and development of respiratory allergy, we investigated the occurrence of a perennial type of symptomatology in children monosensitized to Olea europaea (O.e.) pollen allergens compared with subjects with monosensitization to Parietaria (P) and Gramineae (G) in order to confirm our previous observations in adults. We selected a group of 52 children with rhinitis and/or bronchial asthma and a SPT positivity only to pollens (30 to P, 15 to G, and 7 to O.e.). Using commercially available allergenic extracts and reagents, the following diagnostic procedures were performed: skin prick test (SPT), specific IgE assays (RAST), nonspecific bronchial provocation test (NsBPT) and specific nasal provocation test (sNPT), respectively, in patients with bronchial asthma and rhinitis. Pollen counts and a statistical analysis using Spearman's correlation test were also carried out. Six of seven children with monosensitization to O.e. allergens showed a perennial pattern of symptoms in comparison to 7 of 23 and 3 of 12, respectively, in subjects with P and G pollinosis. All patients with perennial nasal symptoms of O.e. group exhibited a late nasal response after sNPT. Although these findings on nasal response may partially explain the occurrence of a prolonged inflammation of the nose induced by O.e. allergens, we think that other possibilities could be investigated. In our opinion, further studies are necessary using better purified and standardized diagnostic materials and, moreover, a greater number of O.e. monosensitized children living in other geographical areas need to be examined for a comparison of our results with theirs.

  15. On the Use of Leaf Spectral Indices to Assess Water Status and Photosynthetic Limitations in Olea europaea L. during Water-Stress and Recovery

    PubMed Central

    Sun, Pengsen; Wahbi, Said; Tsonev, Tsonko; Haworth, Matthew; Liu, Shirong; Centritto, Mauro

    2014-01-01

    Diffusional limitations to photosynthesis, relative water content (RWC), pigment concentrations and their association with reflectance indices were studied in olive (Olea europaea) saplings subjected to water-stress and re-watering. RWC decreased sharply as drought progressed. Following rewatering, RWC gradually increased to pre-stress values. Photosynthesis (A), stomatal conductance (gs), mesophyll conductance (gm), total conductance (gt), photochemical reflectance index (PRI), water index (WI) and relative depth index (RDI) closely followed RWC. In contrast, carotenoid concentration, the carotenoid to chlorophyll ratio, water content reflectance index (WCRI) and structural independent pigment index (SIPI) showed an opposite trend to that of RWC. Photosynthesis scaled linearly with leaf conductance to CO2; however, A measured under non-photorespiratory conditions (A1%O2) was approximately two times greater than A measured at 21% [O2], indicating that photorespiration likely increased in response to drought. A1%O2 also significantly correlated with leaf conductance parameters. These relationships were apparent in saturation type curves, indicating that under non-photorespiratory conditions, CO2 conductance was not the major limitations to A. PRI was significant correlated with RWC. PRI was also very sensitive to pigment concentrations and photosynthesis, and significantly tracked all CO2 conductance parameters. WI, RDI and WCRI were all significantly correlated with RWC, and most notably to leaf transpiration. Overall, PRI correlated more closely with carotenoid concentration than SIPI; whereas WI tracked leaf transpiration more effectively than RDI and WCRI. This study clearly demonstrates that PRI and WI can be used for the fast detection of physiological traits of olive trees subjected to water-stress. PMID:25136798

  16. Assessing Animal Welfare Impacts in the Management of European Rabbits (Oryctolagus cuniculus), European Moles (Talpa europaea) and Carrion Crows (Corvus corone).

    PubMed

    Baker, Sandra E; Sharp, Trudy M; Macdonald, David W

    2016-01-01

    Human-wildlife conflict is a global issue. Attempts to manage this conflict impact upon wild animal welfare, an issue receiving little attention until relatively recently. Where human activities harm animal welfare these effects should be minimised where possible. However, little is known about the welfare impacts of different wildlife management interventions, and opinions on impacts vary widely. Welfare impacts therefore need to be assessed objectively. Our objectives were to: 1) establish whether an existing welfare assessment model could differentiate and rank the impacts of different wildlife management interventions (for decision-making purposes); 2) identify and evaluate any additional benefits of making formal welfare assessments; and 3) illustrate issues raised by application of the model. We applied the welfare assessment model to interventions commonly used with rabbits (Oryctolagus cuniculus), moles (Talpa europaea) and crows (Corvus corone) in the UK. The model ranked interventions for rabbits (least impact first: fencing, head shot, chest shot) and crows (shooting, scaring, live trapping with cervical dislocation). For moles, managing molehills and tunnels scored least impact. Both spring trapping, and live trapping followed by translocation, scored greater impacts, but these could not be compared directly as they scored on different axes of the model. Some rankings appeared counter-intuitive, highlighting the need for objective formal welfare assessments. As well as ranking the humaneness of interventions, the model highlighted future research needs and how Standard Operating Procedures might be improved. The model is a milestone in assessing wildlife management welfare impacts, but our research revealed some limitations of the model and we discuss likely challenges in resolving these. In future, the model might be developed to improve its utility, e.g. by refining the time-scales. It might also be used to reach consensus among stakeholders about

  17. Effect of water deficit on leaf phenolic composition, gas exchange, oxidative damage and antioxidant activity of four Greek olive (Olea europaea L.) cultivars.

    PubMed

    Petridis, Antonios; Therios, Ioannis; Samouris, Georgios; Koundouras, Stefanos; Giannakoula, Anastasia

    2012-11-01

    The olive tree (Olea europaea L.) is often exposed to severe water stress during the summer season. In this study, we determined the changes in total phenol content, oleuropein and hydroxytyrosol in the leaves of four olive cultivars ('Gaidourelia', 'Kalamon', 'Koroneiki' and 'Megaritiki') grown under water deficit conditions for two months. Furthermore, we investigated the photosynthetic performance in terms of gas exchange and chlorophyll a fluorescence, as well as malondialdehyde content and antioxidant activity. One-year-old self-rooted plants were subjected to three irrigation treatments that received a water amount equivalent to 100% (Control, C), 66% (Field Capacity 66%, FC(66)) and 33% (Field Capacity 33%, FC(33)) of field capacity. Measurements were conducted 30 and 60 days after the initiation of the experiment. Net CO(2) assimilation rate, stomatal conductance and F(v)/F(m) ratio decreased only in FC(33) plants. Photosynthetic rate was reduced mainly due to stomatal closure, but damage to PSII also contributed to this decrease. Water stress induced the accumulation of phenolic compounds, especially oleuropein, suggesting their role as antioxidants. Total phenol content increased in FC(33) treatment and oleuropein presented a slight increase in FC(66) and a sharper one in FC(33) treatment. Hydroxytyrosol showed a gradual decrease as water stress progressed. Malondialdehyde (MDA) content increased due to water stress, mostly after 60 days, while antioxidant activity increased for all cultivars in the FC(33) treatment. 'Gaidourelia' could be considered as the most tolerant among the tested cultivars, showing higher phenolic concentration and antioxidant activity and lower lipid peroxidation and photochemical damage after two months of water stress. The results indicated that water stress affected olive tree physiological and biochemical parameters and magnitude of this effect depended on genotype, the degree of water limitation and duration of treatment

  18. Inhibition of 6-hydroxydopamine-induced PC12 cell apoptosis by olive (Olea europaea L.) leaf extract is performed by its main component oleuropein.

    PubMed

    Pasban-Aliabadi, Hamzeh; Esmaeili-Mahani, Saeed; Sheibani, Vahid; Abbasnejad, Mehdi; Mehdizadeh, Anahita; Yaghoobi, Mohammad Mehdi

    2013-04-01

    Parkinson disease (PD) is the most common progressive neurodegenerative disorder characterized by progressive death of midbrain dopaminergic neurons. Most neurodegenerative disease treatments are, at present, palliative. However, some natural herbal products have been shown to rescue neurons from death and apoptosis in some of neurodegenerative diseases. Not only Olea europaea L. olive oil, but also the leaves of this plant have been used for medical purposes. Olive leaf extract (OLE) is being used by people as a drink across the world and as an integral ingredient in their desire to maintain and improve their health. Here, we investigated the effects of OLE and its main phenolic component oleuropein on 6-hydroxydopamine (6-OHDA)-induced toxicity in rat adrenal pheochromocytoma (PC12) cells as an in vitro model of PD. Cell damage was induced by 150 μM 6-OHDA. The cell survival rate was examined by MTT assay. Generation of intra-cellular reactive oxygen species (ROS) was studied using fluorescence spectrophotometry. Immunoblotting and DNA analysis were also employed to determine the levels of biochemical markers of apoptosis in the cells. The data showed that 6-OHDA could decrease the viability of the cells. In addition, intra-cellular ROS, activated caspase 3, Bax/Bcl-2 ratio, as well as DNA fragmentation were significantly increased in 6-OHDA-treated cells. Incubation of cells with OLE (400 and 600 μg/mL) and oleuropein (20 and 25 μg/mL) could decrease cell damage and reduce biochemical markers of cell death. The results suggest that OLE and oleuropein have anti-oxidant protective effects against 6-OHDA-induced PC12 cell damage. The protective effects of OLE and oleuropein are correlative with their anti-oxidative and anti-apoptotic properties and suggest their therapeutic potential in the treatment of PD.

  19. Biochemistry of Ammonia Monoxygenase from Nitrosomonas

    SciTech Connect

    Alan Hooper

    2009-07-15

    Major results. 1. CytochromecM552, a protein in the electron transfer chain to ammonia monooxygenase. Purification, modeling of protein structure based on primary structure, characterization of 4 hemes by magnetic spectroscopy, potentiometry, ligand binding and turnover. Kim, H. J., ,Zatsman, et al. 2008). 2. Characterization of proteins which thought to be involved in the AMO reaction or to protect AMO from toxic nitrogenous intermediates such as NO. Nitrosocyanin is a protein present only in bacteria which catalyze the ammonia monoxygenase reaction (1). Cytochrome c P460 beta and cytochrome c’ beta.

  20. Identification and Assessment of the Potential Allergenicity of 7S Vicilins in Olive (Olea europaea L.) Seeds

    PubMed Central

    Jimenez-Lopez, Jose C.; Zafra, Adoración; Palanco, Lucía; Florido, José Fernando

    2016-01-01

    Olive seeds, which are a raw material of interest, have been reported to contain 11S seed storage proteins (SSPs). However, the presence of SSPs such as 7S vicilins has not been studied. In this study, following a search in the olive seed transcriptome, 58 sequences corresponding to 7S vicilins were retrieved. A partial sequence was amplified by PCR from olive seed cDNA and subjected to phylogenetic analysis with other sequences. Structural analysis showed that olive 7S vicilin contains 9 α-helixes and 22 β-sheets. Additionally, 3D structural analysis displayed good superimposition with vicilin models generated from Pistacia and Sesamum. In order to assess potential allergenicity, T and B epitopes present in these proteins were identified by bioinformatic approaches. Different motifs were observed among the species, as well as some species-specific motifs. Finally, expression analysis of vicilins was carried out in protein extracts obtained from seeds of different species, including the olive. Noticeable bands were observed for all species in the 15–75 kDa MW interval, which were compatible with vicilins. The reactivity of the extracts to sera from patients allergic to nuts was also analysed. The findings with regard to the potential use of olive seed as food are discussed. PMID:27034939

  1. Identification and Assessment of the Potential Allergenicity of 7S Vicilins in Olive (Olea europaea L.) Seeds.

    PubMed

    Jimenez-Lopez, Jose C; Zafra, Adoración; Palanco, Lucía; Florido, José Fernando; Alché, Juan de Dios

    2016-01-01

    Olive seeds, which are a raw material of interest, have been reported to contain 11S seed storage proteins (SSPs). However, the presence of SSPs such as 7S vicilins has not been studied. In this study, following a search in the olive seed transcriptome, 58 sequences corresponding to 7S vicilins were retrieved. A partial sequence was amplified by PCR from olive seed cDNA and subjected to phylogenetic analysis with other sequences. Structural analysis showed that olive 7S vicilin contains 9 α-helixes and 22 β-sheets. Additionally, 3D structural analysis displayed good superimposition with vicilin models generated from Pistacia and Sesamum. In order to assess potential allergenicity, T and B epitopes present in these proteins were identified by bioinformatic approaches. Different motifs were observed among the species, as well as some species-specific motifs. Finally, expression analysis of vicilins was carried out in protein extracts obtained from seeds of different species, including the olive. Noticeable bands were observed for all species in the 15-75 kDa MW interval, which were compatible with vicilins. The reactivity of the extracts to sera from patients allergic to nuts was also analysed. The findings with regard to the potential use of olive seed as food are discussed.

  2. Cell density-regulated recovery of starved biofilm populations of ammonia-oxidizing bacteria.

    PubMed Central

    Batchelor, S E; Cooper, M; Chhabra, S R; Glover, L A; Stewart, G S; Williams, P; Prosser, J I

    1997-01-01

    The speed of recovery of cell suspensions and biofilm populations of the ammonia oxidizer Nitrosomonas europaea, following starvation was determined. Stationary-phase cells, washed and resuspended in ammoniumfree inorganic medium, were starved for periods of up to 42 days, after which the medium was supplemented with ammonium and subsequent growth was monitored by measuring nitrite concentration changes. Cultures exhibited a lag phase prior to exponential nitrite production, which increased from 8.72 h (no starvation) to 153 h after starvation for 42 days. Biofilm populations of N. europaea colonizing sand or soil particles in continuous-flow, fixed column reactors were starved by continuous supply of ammonium-free medium. Following resupply of ammonium, starved biofilms exhibited no lag phase prior to nitrite production, even after starvation for 43.2 days, although there was evidence of cell loss during starvation. Biofilm formation will therefore provide a significant ecological advantage for ammonia oxidizers in natural environments in which the substrate supply is intermittent. Cell density-dependent phenomena in a number of gram-negative bacteria are mediated by N-acyl homoserine lactones (AHL), including N-(3-oxohexanoyl)-L-homoserine lactone (OHHL). Addition of both ammonium and OHHL to cell suspensions starved for 28 days decreased the lag phase in a concentration-dependent manner from 53.4 h to a minimum of 10.8 h. AHL production by N. europaea was detected by using a luxR-luxAB AHL reporter system. The results suggest that rapid recovery of high-density biofilm populations may be due to production and accumulation of OHHL to levels not possible in relatively low-density cell suspensions. PMID:9172348

  3. The effect of the hexanic extracts of fig (Ficus carica) and olive (Olea europaea) fruit and nanoparticles of selenium on the immunogenicity of the inactivated avian influenza virus subtype H9N2.

    PubMed

    Asl Najjari, Amir Hossein; Rajabi, Zolfaghar; Vasfi Marandi, Mehdi; Dehghan, Gholamreza

    2015-01-01

    Influenza is a contagious viral disease that is seen in avian, human and other mammals, so its control is important. Vaccination against influenza virus subtype H9N2 is one of the ways in controlling program, for this reason several vaccines has been produced. Recently, application of inactivated oil-emulsion vaccines in poultry for controlling low pathogenic avian influenza is increasing. At present, oils that are used as adjuvant in commercial vaccines are mineral oils, which not only lack immunizing effect, but also produce some detriments. The aim of this study is the evaluation the immunogenicity of vegetable oils, which are more metabolizable and safer than mineral oils. In this study the efficacy of hexanic extracts of fig (Ficus carica) and olive (Olea europaea) fruit and also nano-selenium on the immunogenicity of the inactivated avian influenza virus subtype H9N2 was evaluated in broiler chickens. The results indicated that the prepared emulsions could elicit a little degree of immunity, but they could not inhibit the anamnestic response and infection. With regard to the results, it seems that the intact mixture of fig and olive fruit hexanic extracts could not be administered as an immunoadjuvant in the vaccine, and about nano-selenium. In spite of positive effect on the immunogenicity of avian influenza virus subtype H9N2, it still needs more work.

  4. The effect of oleuropein from olive leaf (Olea europaea) extract on Ca²⁺ homeostasis, cytotoxicity, cell cycle distribution and ROS signaling in HepG2 human hepatoma cells.

    PubMed

    Cheng, Jin-Shiung; Chou, Chiang-Ting; Liu, Yuan-Yuarn; Sun, Wei-Chih; Shieh, Pochuen; Kuo, Daih-Huang; Kuo, Chun-Chi; Jan, Chung-Ren; Liang, Wei-Zhe

    2016-05-01

    Oleuropein, a phenolic compound found in the olive leaf (Olea europaea), has been shown to have biological activities in different models. However, the effects of oleuropein on Ca(2+) homeostasis, cytotoxicity, cell cycle distribution and ROS signaling in liver cells have not been analyzed. Oleuropein induced [Ca(2+)]i rises only in HepG2 cells but not in AML12, HA22T or HA59T cells due to the different status of 3-hydroxy-3-methylglutaryl-CoA reductase expression. In HepG2 cells, this Ca(2+) signaling response was reduced by removing extracellular Ca(2+), and was inhibited by the store-operated Ca(2+) channel blockers 2-APB and SKF96365. In Ca(2+)-free medium, pretreatment with the ER Ca(2+) pump inhibitor thapsigargin abolished oleuropein-induced [Ca(2+)]i rises. Oleuropein induced cell cycle arrest which was associated with the regulation of p53, p21, CDK1 and cyclin B1 levels. Furthermore, oleuropein elevated intracellular ROS levels but reduced GSH levels. Treatment with the intracellular Ca(2+) chelator BAPTA-AM or the antioxidant NAC partially reversed oleuropein-induced cytotoxicity. Together, in HepG2 cells, oleuropein induced [Ca(2+)]i rises by releasing Ca(2+) from the ER and causing Ca(2+) influx through store-operated Ca(2+) channels. Moreover, oleuropein induced Ca(2+)-associated cytotoxicity that involved ROS signaling and cell cycle arrest. This compound may offer a potential therapy for treatment of human hepatoma.

  5. Nitrification inhibitors from the roots of Leucaena leucocephala.

    PubMed

    Erickson, A J; Ramsewak, R S; Smucker, A J; Nair, M G

    2000-12-01

    The nitrification inhibition (NI) bioassay guided fractionation of the methanol extract of lyophilized and milled roots of Leuceana leucocephala resulted in the isolation of four compounds, 1-4, as confirmed from their 1H and 13C NMR spectral data. Compound 1, gallocatechin, was the most active NI inhibitor at 12 microg/mL. Epigallocatechin, 2, and epicatechin, 4, isolated as mixtures, were not assayed individually for their NI inhibitory activities against the nitrification bacterium Nitrosomonas europaea.

  6. Regulation of the genes involved in nitrification.

    SciTech Connect

    Arp, D.J.; Sayavedra-Soto, L.A.

    2003-08-14

    OAK-B135 This project focuses on the characterization of the regulation of the genes involved in nitrification in the bacterium Nitrosomonas europaea. The key genes in the nitrification pathway, amo and hao, are present in multiple copies in the genome. The promoters for these genes were identified and characterized. It was shown that there were some differences in the transcriptional regulation of the copies of these genes.

  7. Treatability Study in Support of the Intrinsic Remediation Option at the Current Fire Training Area, Westover Air Reserves Base, Chicopee, Massachusetts

    DTIC Science & Technology

    1997-02-01

    physical and chemical conditions of the groundwater and phreat’. soil at the site are not likely to 0 inhibit microorganism growth . Fuel-hydrocarbon...Arciero, D., Vannelli, T., Logan, M., and Hooper, A.B., 1989, Degradation of trichloroethylene by the ammonia-oxidizing bacterium Nitrosomonas europaea ...5-3 5.3.1 Grid Design and Boundary Conditions ..................................... 5-3 5.3.2 Groundwater Elevation and

  8. Nitrification Enhancement through pH Control with Rotating Biological Contactors

    DTIC Science & Technology

    1981-09-01

    Inst. of Sew. Purif., 130 (1964). 31. Engel, M. S. and M. Alexander, " Growth and Autotrophic Metabolism of Nitrosomonas Europaea ," Jour. Bact., 76, 217...relative effectiveness of four different alkaline chemicals on enhancing the nitrifying process under optimum pH conditions was evaluated in Phase II...111 6.12 Relative RBC Heterotrophic Bacteria Growth Under pH Conditions from pH 7.0 to pH 8.5 ....... ............. .. 112 6.13 Batch Alkalinity

  9. Developing and Validating Genetic Catabolic Probes for Monitored Natural Attenuation of 1,4-Dioxane with a One-Year Timeframe

    DTIC Science & Technology

    2014-04-01

    concentrations were determined by Nanodrop ND-1000 from Nanodrop products Inc. (Wilmington, NE). cDNA was synthesized using High-Capacity cDNA Reverse...ACG CCT ATT - (ZEN) - ACA TCC AGC AGC TCG A - (IABkFQ) -3’. The amplicons were approximately 115 bp in length. All primers and probes were synthesized ...MC09 − + - - - Escherichia coli K12 − + - - - Bacteriophage λ − − amo Ammonia MO - Nitrosomonas europaea Winogradsky − + tod Toluene DO

  10. Generation of polymerase chain reaction-specific probes for library screening using single degenerate primers.

    PubMed

    Hommes, N G; Arp, D J; Sayavedra-Soto, L A

    1995-03-01

    Degenerate oligonucleotide primers were made to peptide sequences from hydroxylamine oxidoreductase (HAO) from Nitrosomonas europaea. The primers were used singly in PCR reactions to amplify portions of the gene for HAO from genomic DNA. Southern hybridizations using fragments amplified with each primer showed that they labeled the same genomic DNA fragments. The PCR-amplified fragments were successfully used to screen a gene library for clones containing the HAO gene. The method of isolating genes by PCR with single primers has general utility.

  11. The effects of salinity on nitrification using halophilic nitrifiers in a Sequencing Batch Reactor treating hypersaline wastewater

    PubMed Central

    Cui, You-Wei; Zhang, Hong-Yu; Ding, Jie-Ran; Peng, Yong-Zhen

    2016-01-01

    With annual increases in the generation and use of saline wastewater, the need to avoid environmental problems such as eutrophication is critical. A previous study identified ways to start up a halophilic sludge domesticated from estuarine sediments to remove nitrogen from wastewater with a salinity of 30 g/L. This investigation expands that work to explore the impact of salinity on nitrogen removal. This study demonstrated that the mixed halophilic consortia removed nitrogen from wastewater with a salinity of 30–85 g/L. A kinetic analysis showed that halophilic nitrifiers selected based on hypersalinity were characterized by low Ks, μmax and specific ammonium oxidization rates. This explains the decrease in ammonium removal efficiency in the high salinity operational phases. Salinity inhibited ammonia oxidizing bacteria (AOB) activity, as well as the number of dominant AOB, but did not significantly affect the AOB dominant species. Three most dominant AOB lineages in the halophilic sludge were Nitrosomonas marina, Nitrosomonas europaea, and Nitrosococcus mobilis. Nitrosomonas europaea and Nitrosococcus mobilis were mainly affected by salinity, while nitrite accumulation and ammonia loading played the key role in determining the abundance of Nitrosococcus mobilis and Nitrosococcus europaea. The study contributes insights about shifts in halophilic nitrifying bacterial populations. PMID:27109617

  12. SHORT REPORT

    PubMed Central

    Gu, S. H.; Dormion, J.; Hugot, J.-P.; Yanagihara, R.

    2014-01-01

    SUMMARY Recent discovery of genetically distinct hantaviruses in shrews and moles (order Soricomorpha, family Soricidae and Talpidae) has challenged the conventional view that rodents serve as the principal reservoir hosts. Nova virus (NVAV), previously identified in archival liver tissue of a single European mole (Talpa europaea) from Hungary, represents one of the most highly divergent hantaviruses identified to date. To ascertain the spatial distribution and genetic diversity of NVAV, we employed RT–PCR to analyse lungs from 94 moles, captured in two locations in France, during October 2012 to March 2013. NVAV was detected in more than 60% of moles at each location, suggesting efficient enzootic virus transmission and confirming that this mole species serves as the reservoir host. Although the pathogenic potential of NVAV is unknown, the widespread geographical distribution of the European mole might pose a hantavirus exposure risk for humans. PMID:24044372

  13. A defence-related Olea europaea β-glucosidase hydrolyses and activates oleuropein into a potent protein cross-linking agent.

    PubMed

    Koudounas, Konstantinos; Banilas, Georgios; Michaelidis, Christos; Demoliou, Catherine; Rigas, Stamatis; Hatzopoulos, Polydefkis

    2015-04-01

    Oleuropein, the major secoiridoid compound in olive, is involved in a sophisticated two-component defence system comprising a β-glucosidase enzyme that activates oleuropein into a toxic glutaraldehyde-like structure. Although oleuropein deglycosylation studies have been monitored extensively, an oleuropein β-glucosidase gene has not been characterized as yet. Here, we report the isolation of OeGLU cDNA from olive encoding a β-glucosidase belonging to the defence-related group of terpenoid-specific glucosidases. In planta recombinant protein expression assays showed that OeGLU deglycosylated and activated oleuropein into a strong protein cross-linker. Homology and docking modelling predicted that OeGLU has a characteristic (β/α)8 TIM barrel conformation and a typical construction of a pocket-shaped substrate recognition domain composed of conserved amino acids supporting the β-glucosidase activity and non-conserved residues associated with aglycon specificity. Transcriptional analysis in various olive organs revealed that the gene was developmentally regulated, with its transcript levels coinciding well with the spatiotemporal patterns of oleuropein degradation and aglycon accumulation in drupes. OeGLU upregulation in young organs reflects its prominent role in oleuropein-mediated defence system. High gene expression during drupe maturation implies an additional role in olive secondary metabolism, through the degradation of oleuropein and reutilization of hydrolysis products.

  14. Transcript levels of CHL P gene, antioxidants and chlorophylls contents in olive (Olea europaea L.) pericarps: a comparative study on eleven olive cultivars harvested in two ripening stages.

    PubMed

    Muzzalupo, Innocenzo; Stefanizzi, Francesca; Perri, Enzo; Chiappetta, Adriana Ada

    2011-03-01

    The effects of ripening stage on the antioxidant content in olive pericarps were evaluated in eleven olive genotypes grown in the same bioagronomic conditions in Southern Italy. We examined the transcript levels of geranylgeranyl reductase (CHL P) gene and the content of tocopherols, phenolic compounds and chlorophylls in the pericarps. The examined genotypes showed an increase of CHL P transcripts during pericarps ripening. Significant differences were reported in the antioxidant proportions in the same cultivars at different pericarp ripening stage. We show an inverse correlation between phenols and tocopherols content. In particular, during the ripening phase, tocopherols increased rapidly in olive pericarps while phenolic compounds and chlorophyll levels declined significantly. The significant amounts of these antioxidants confirm the nutritional and medicinal value of olive drupes and its products (table olives and olive oil). We suggest, for the first time, a link between CHL P transcript levels and tocopherols content during the ripening of olive pericarps. Besides, we revealed that this trend of CHL P transcript levels during pericarps ripening is independent from the olive genotypes.

  15. Evolution of Sucrose Synthesis[w

    PubMed Central

    Lunn, John Edward

    2002-01-01

    Cyanobacteria and proteobacteria (purple bacteria) are the only prokaryotes known to synthesize sucrose (Suc). Suc-P synthase, Suc-phosphatase (SPP), and Suc synthase activities have previously been detected in several cyanobacteria, and genes coding for Suc-P synthase (sps) and Suc synthase (sus) have been cloned from Synechocystis sp. PCC 6803 and Anabaena (Nostoc) spp., respectively. An open reading frame in the Synechocystis genome encodes a predicted 27-kD polypeptide that shows homology to the maize (Zea mays) SPP. Heterologous expression of this putative spp gene in Escherichia coli, reported here, confirmed that this open reading frame encodes a functional SPP enzyme. The Synechocystis SPP is highly specific for Suc-6F-P (Km = 7.5 μm) and is Mg2+ dependent (Ka = 70 μm), with a specific activity of 46 μmol min−1 mg−1 protein. Like the maize SPP, the Synechocystis SPP belongs to the haloacid dehalogenase superfamily of phosphatases/hydrolases. Searches of sequenced microbial genomes revealed homologs of the Synechocystis sps gene in several other cyanobacteria (Nostoc punctiforme, Prochlorococcus marinus strains MED4 and MIT9313, and Synechococcus sp. WH8012), and in three proteobacteria (Acidithiobacillus ferrooxidans, Magnetococcus sp. MC1, and Nitrosomonas europaea). Homologs of the Synechocystis spp gene were found in Magnetococcus sp. MC1 and N. punctiforme, and of the Anabaena sus gene in N. punctiforme and N. europaea. From analysis of these sequences, it is suggested that Suc synthesis originated in the proteobacteria or a common ancestor of the proteobacteria and cyanobacteria. PMID:11950997

  16. Influence of soil moisture on linear alkylbenzene sulfonate-induced toxicity in ammonia-oxidizing bacteria.

    PubMed

    Nielsen, Klaus B; Brandt, Kristian K; Jacobsen, Anne-Marie; Mortensen, Gerda K; Sørensen, Jan

    2004-02-01

    Moisture affects bioavailability and fate of pollutants in soil, but very little is known about moisture-induced effects on pollutant toxicity. We here report on a modifying effect of moisture on degradation of linear alkylbenzene sulfonates (LASs) and on their toxicity towards ammonia-oxidizing bacteria (AOB) in agricultural soil. In soil spiked with two LAS levels (250 or 1,000 mg/kg) and incubated at four different moisture levels (9-100% of water-holding capacity), degradation was strongly affected by both soil moisture and initial LAS concentration, resulting in degradation half-lives ranging from 13 to more than 160 d. Toxicity towards AOB assessed by a novel Nitrosomonas europaea luxAB-reporter assay was correlated to total LAS concentration, indicating that LAS remained bioavailable over time without accumulation of toxic intermediates. Toxicity towards indigenous AOB increased with increasing soil moisture. The results indicate that dry soil conditions inhibit LAS degradation and provide protection against toxicity within the indigenous AOB, thus allowing for a rapid recovery of this population when LAS degradation is resumed and completed after rewetting. We propose that the protection of microbial populations against toxicity in dry soil may be a general phenomenon caused primarily by limited diffusion and thus a low bioavailability of the toxicant.

  17. Non-invasive self-referencing electrochemical sensors for quantifying real-time biofilm analyte flux.

    PubMed

    McLamore, E S; Porterfield, D M; Banks, M K

    2009-02-15

    Current techniques for characterizing biofilm physiology lack the signal filtering capability required for quantifying signals associated with real time biologically active transport. Though a great deal was learned from previous investigations, no results have been reported on the characterization of in vivo, real time biofilm flux using non-invasive (non-destructive) techniques. This article introduces the self-referencing technique for applications in biofilm physiology. Self-referencing is a non-invasive sensing modality which is capable of sensing changes in biologically active analyte flux as small as 10 fmol cm(-2) s(-1). Studies directly characterizing flux, as opposed to concentration, have the advantage of quantifying real time changes in biologically active transport which are otherwise lost to background noise. The use of this modality for characterizing biofilm physiology is validated with a reversible enzyme inhibition study. The experiment used self-referencing potentiometric sensors for quantifying real time ammonium and nitrite flux. Amperometric and optical sensing methods, though not presented herein, are also powerful sensing tools which benefit from operation in self-referencing mode. Reversible ammonia monooxygenase inhibition by a copper chelator (thiourea), and subsequent relief by excess copper addition was successfully demonstrated using self-referencing ion-selective microelectrodes for a mature Nitrosomonas europaea biofilm.

  18. Long term assessment of factors affecting nitrifying bacteria communities and N-removal in a full-scale biological process treating high strength hazardous wastewater.

    PubMed

    Kim, Young Mo; Park, Hongkeun; Cho, Kyung Hwa; Park, Jong Moon

    2013-04-01

    Over a 3 year period, interactions between nitrifying bacterial communities and the operational parameters of a full-scale wastewater treatment plant were analyzed to assess their impact on nitrification performance. Throughout the study period, nitrification fluctuated while Nitrosomonas europaea and Nitrosomonas nitrosa, the two major ammonia oxidizing bacteria (AOB) communities, showed resistance to changes in operational and environmental conditions. Nitrobacter populations mostly exceeded those of Nitrospira within nitrite oxidizing bacteria (NOB). Meanwhile, principal component analysis (PCA) results revealed that a close association between Nitrobacter and nitrite concentration as well as a direct correlation between the quantity of AOB and influent SCN- concentration. The serial shifts of data points over time showed that the nitrification of a full-scale treatment plant has been gradually suppressed by the influence of influent COD and phenol concentrations.

  19. Microbial biogeography across a full-scale wastewater treatment plant transect: evidence for immigration between coupled processes.

    PubMed

    Wells, George F; Wu, Cindy H; Piceno, Yvette M; Eggleston, Brad; Brodie, Eoin L; Desantis, Todd Z; Andersen, Gary L; Hazen, Terry C; Francis, Christopher A; Criddle, Craig S

    2014-05-01

    Wastewater treatment plants use a variety of bioreactor types and configurations to remove organic matter and nutrients. Little is known regarding the effects of different configurations and within-plant immigration on microbial community dynamics. Previously, we found that the structure of ammonia-oxidizing bacterial (AOB) communities in a full-scale dispersed growth activated sludge bioreactor correlated strongly with levels of NO2 (-) entering the reactor from an upstream trickling filter. Here, to further examine this puzzling association, we profile within-plant microbial biogeography (spatial variation) and test the hypothesis that substantial microbial immigration occurs along a transect (raw influent, trickling filter biofilm, trickling filter effluent, and activated sludge) at the same full-scale wastewater treatment plant. AOB amoA gene abundance increased >30-fold between influent and trickling filter effluent concomitant with NO2 (-) production, indicating unexpected growth and activity of AOB within the trickling filter. Nitrosomonas europaea was the dominant AOB phylotype in trickling filter biofilm and effluent, while a distinct "Nitrosomonas-like" lineage dominated in activated sludge. Prior time series indicated that this "Nitrosomonas-like" lineage was dominant when NO2 (-) levels in the trickling filter effluent (i.e., activated sludge influent) were low, while N. europaea became dominant in the activated sludge when NO2 (-) levels were high. This is consistent with the hypothesis that NO2 (-) production may cooccur with biofilm sloughing, releasing N. europaea from the trickling filter into the activated sludge bioreactor. Phylogenetic microarray (PhyloChip) analyses revealed significant spatial variation in taxonomic diversity, including a large excess of methanogens in the trickling filter relative to activated sludge and attenuation of Enterobacteriaceae across the transect, and demonstrated transport of a highly diverse microbial community

  20. 3,3',5,5'-tetramethylbenzidine/H2O2 staining is not specific for heme proteins separated by gel electrophoresis.

    PubMed

    Miller, D J; Nicholas, D J

    1984-08-01

    Staining of sodium dodecyl sulfate or lithium dodecyl sulfate gels with 3,3',5,5'-tetramethylbenzidine (TMBZ)/H2O2 after electrophoresis has frequently been used as a specific method of detecting heme proteins. That TMBZ is an electron donor for O2 reduction by the nonheme-soluble cytochrome oxidase/nitrite reductase from Nitrosomonas europaea is now shown; this protein is detected by the TMBZ/H2O2 method. A method for the determination of TMBZ oxidase activity is given; hence, the detection of artifactual staining due to proteins of this type is possible.

  1. The Second Conference on the Environmental Chemistry of Hydrazine Fuels; 15 February 1979.

    DTIC Science & Technology

    1982-04-01

    compounds under various test conditions . The "no effect" or safe conientration (SC) were determined by using a t-test to compare mean growth in the...for UDMH was measured after six days of growth . Both SC and EC5 0 are higher under seawater conditions than under freshwater conditions for hydrazine...Nicholas, D.J., and O.T. Jones, "Oxidation of Hydroxylamine in Cell-Free Extracts of Nitrosomonas europaea ." Nature, 185, 512, (1960). 10. Private

  2. Isotopomeric characterization of nitrous oxide produced by reaction of enzymes extracted from nitrifying and denitrifying bacteria

    NASA Astrophysics Data System (ADS)

    Yamazaki, T.; Hozuki, T.; Arai, K.; Toyoda, S.; Koba, K.; Fujiwara, T.; Yoshida, N.

    2014-05-01

    Nitrous oxide (N2O) is a potent greenhouse gas and produced in denitrification and nitrification by various microorganisms. Site preference (SP) of 15N in N2O, which is defined as the difference in the natural abundance of isotopomers 14N15NO and 15N14NO relative to 14N14NO, has been reported to be a useful tool to quantitatively distinguish N2O production pathways. To determine representative SP values for each microbial process, we firstly measured SP of N2O produced in the enzyme reaction of hydroxylamine oxidoreductase (HAO) purified from two species of ammonia oxidizing bacteria (AOB), Nitrosomonas europaea and Nitrosococcus oceani, and that of nitric oxide reductase (NOR) from Paracoccus denitrificans. The SP value for NOR reaction (-5.9 ± 2.1‰) showed nearly the same value as that reported for N2O produced by P. denitrificans in pure culture. In contrast, SP value for HAO reaction (36.3 ± 2.3‰) was a little higher than the values reported for N2O produced by AOB in aerobic pure culture. Using the SP values obtained by HAO and NOR reactions, we calculated relative contribution of the nitrite (NO2-) reduction (which is followed by NO reduction) to N2O production by N. oceani incubated under different O2 availability. Our calculations revealed that previous in vivo studies might have underestimated the SP value for the NH2OH oxidation pathway possibly due to a small contribution of NO2- reduction pathway. Further evaluation of isotopomer signatures of N2O using common enzymes of other processes related to N2O would improve the isotopomer analysis of N2O in various environments.

  3. Isotopomeric characterization of nitrous oxide produced by reaction of enzymes extracted from nitrifying and denitrifying bacteria

    NASA Astrophysics Data System (ADS)

    Yamazaki, T.; Hozuki, T.; Arai, K.; Toyoda, S.; Koba, K.; Fujiwara, T.; Yoshida, N.

    2013-10-01

    Nitrous oxide (N2O) is a potent greenhouse gas and produced in denitrification and nitrification in environmental nitrogen cycle by various microorganism. Site preference (SP) of 15N in N2O, which is defined as the difference in the natural abundance of isotopomers 14N15NO and 15N14NO relative to 14N14NO, has been reported to be a useful tool to quantitatively distinguish N2O production pathway. To determine representative SP value for each microbial process, we firstly measured SP of N2O produced in the enzyme reaction of hydroxylamine oxidoreductase (HAO) purified from two species of ammonia oxidizing bacteria (AOB), Nitrosomonas europaea and Nitrosococcus oceani, and that of nitric oxide reductase (NOR) from Paracoccus denitrificans, respectively. The SP value for NOR reaction (-5.9 ± 2.1‰) showed nearly the same value as that reported for N2O produced by P. denitrificans in pure culture. In contrast, SP value for HAO reaction (36.3 ± 2.3‰) was a little higher than the values reported for N2O produced by AOB in aerobic pure culture. Using the SP values obtained by HAO and NOR reactions, we calculated relative contribution of the nitrite (NO2-) reduction (which is followed by NO reduction) to N2O production by N. oceani incubated under different O2 availability. Our calculations revealed that previous in vivo studies might have underestimated the SP value for NH2OH oxidation pathway possibly due to a small contribution of NO2- reduction pathway. Further evaluation of isotopomer signatures of N2O using common enzymes of other processes related to N2O would improve the isotopomer analysis of N2O in various environments.

  4. Analysis of ammonia-oxidizing bacteria dominating in lab-scale bioreactors with high ammonium bicarbonate loading.

    PubMed

    Vejmelkova, Dana; Sorokin, Dimitry Y; Abbas, Ben; Kovaleva, Olga L; Kleerebezem, Robbert; Kampschreur, Marlies J; Muyzer, Gerard; van Loosdrecht, Mark C M

    2012-01-01

    The ammonia-oxidizing bacterial community (AOB) was investigated in two types of laboratory-scale bioreactors performing partial oxidation of ammonia to nitrite or nitrate at high (80 mM) to extremely high (428 mM) concentrations of ammonium bicarbonate. At all conditions, the dominant AOB was affiliated to the Nitrosomonas europaea lineage as was determined by fluorescence in situ hybridization and polymerase chain reaction in combination with denaturing gradient gel electrophoresis. Molecular analysis of the mixed populations, based on the 16S rRNA and cbbL genes, demonstrated the presence of two different phylotypes of Nitrosomonas, while microbiological analysis produced a single phylotype, represented by three different morphotypes. One of the most striking features of the AOB populations encountered in the bioreactors was the domination of highly aggregated obligate microaerophilic Nitrosomonas, with unusual cellular and colony morphology, commonly observed in nitrifying bioreactors but rarely investigated by cultural methods. The latter is probably not an adaptation to stressful conditions created by high ammonia or nitrite concentrations, but oxygen seems to be a stressful factor in these bioreactors.

  5. Whole-Organ analysis of calcium behaviour in the developing pistil of olive (Olea europaea L.) as a tool for the determination of key events in sexual plant reproduction

    PubMed Central

    2011-01-01

    Background The pistil is a place where multiple interactions between cells of different types, origin, and function occur. Ca2+ is one of the key signal molecules in plants and animals. Despite the numerous studies on Ca2+ signalling during pollen-pistil interactions, which constitute one of the main topics of plant physiology, studies on Ca2+ dynamics in the pistil during flower formation are scarce. The purpose of this study was to analyze the contents and in situ localization of Ca2+ at the whole-organ level in the pistil of olive during the whole course of flower development. Results The obtained results showed significant changes in Ca2+ levels and distribution during olive pistil development. In the flower buds, the lowest levels of detectable Ca2+ were observed. As flower development proceeded, the Ca2+ amount in the pistil successively increased and reached the highest levels just after anther dehiscence. When the anthers and petals fell down a dramatic but not complete drop in calcium contents occurred in all pistil parts. In situ Ca2+ localization showed a gradual accumulation on the stigma, and further expansion toward the style and the ovary after anther dehiscence. At the post-anthesis phase, the Ca2+ signal on the stigmatic surface decreased, but in the ovary a specific accumulation of calcium was observed only in one of the four ovules. Ultrastructural localization confirmed the presence of Ca2+ in the intracellular matrix and in the exudate secreted by stigmatic papillae. Conclusions This is the first report to analyze calcium in the olive pistil during its development. According to our results in situ calcium localization by Fluo-3 AM injection is an effective tool to follow the pistil maturity degree and the spatial organization of calcium-dependent events of sexual reproduction occurring in developing pistil of angiosperms. The progressive increase of the Ca2+ pool during olive pistil development shown by us reflects the degree of pistil maturity

  6. High-rate, high-yield production of methanol by ammonia-oxidizing bacteria.

    PubMed

    Taher, Edris; Chandran, Kartik

    2013-04-02

    The overall goal of this study was to develop an appropriate biological process for achieving autotrophic conversion of methane (CH(4)) to methanol (CH3OH). In this study, we employed ammonia-oxidizing bacteria (AOB) to selectively and partially oxidize CH(4) to CH(3)OH. In fed-batch reactors using mixed nitrifying enrichment cultures from a continuous bioreactor, up to 59.89 ± 1.12 mg COD/L of CH(3)OH was produced within an incubation time of 7 h, which is approximately ten times the yield obtained previously using pure cultures of Nitrosomonas europaea. The maximum specific rate of CH(4) to CH(3)OH conversion obtained during this study was 0.82 mg CH(3)OH COD/mg AOB biomass COD-d, which is 1.5 times the highest value reported with pure cultures. Notwithstanding these positive results, CH(4) oxidation to CH(3)OH by AOB was inhibited by NH(3) (the primary substrate for the oxidative enzyme, ammonia monooxygenase, AMO) as well as the product, CH(3)OH, itself. Further, oxidation of CH(4) to CH(3)OH by AOB was also limited by reducing equivalents supply, which could be overcome by externally supplying hydroxylamine (NH(2)OH) as an electron donor. Therefore, a potential optimum design for promoting CH(4) to CH(3)OH oxidation by AOB could involve supplying NH(3) (needed to maintain AMO activity) uncoupled from the supply of NH(2)OH and CH(4). Partial oxidation of CH(4)-containing gases to CH3OH by AOB represents an attractive platform for the conversion of a gaseous mixture to an aqueous compound, which could be used as a commodity chemical. Alternately, the nitrate and CH(3) OH thus produced could be channeled to a downstream anoxic zone in a biological nitrogen removal process to effect nitrate reduction to N(2), using an internally produced organic electron donor.

  7. Nitrous oxide production and methane oxidation by different ammonia-oxidizing bacteria

    SciTech Connect

    Jiang, Q.Q.; Bakken, L.R.

    1999-06-01

    Ammonia-oxidizing bacteria (AOB) are thought to contribute significantly to N{sub 2}O production and methane oxidation in soils. Most knowledge derives from experiments with Nitrosomonas europaea, which appears to be of minor importance in most soils compared to Nitrosospira spp. The authors have conducted a comparative study of levels of aerobic N{sub 2}O production in six phylogenetically different Nitrosospira strains newly isolated from soils and in two N. europaea and Nitrosospira multiformis type strains. The fraction of oxidized ammonium released as N{sub 2}O during aerobic growth was remarkably constant for all the Nitrosospira strains, irrespective of the substrate supply (urea versus ammonium), the pH, or substrate limitation. N. europaea and Nitrosospira multiformis released similar fractions of N{sub 2}O when they were supplied with ample amounts of substrates, but the fractions rose sharply when they were restricted by a low pH or substrate limitation. Phosphate buffer doubled the N{sub 2}O release for all types of AOB. No detectable oxidation of atmospheric methane was detected. Calculations based on detection limits as well as data in the literature on CH{sub 4} oxidation by AOB bacteria prove that none of the tested strains contribute significantly to the oxidation of atmospheric CH{sub 4} in soils.

  8. Effects of simulated rare earth recycling wastewaters on biological nitrification

    DOE PAGES

    Fujita, Yoshiko; Barnes, Joni; Eslamimanesh, Ali; ...

    2015-07-16

    Current efforts to increase domestic availability of rare-earth element (REE) supplies by recycling and expanded ore processing efforts will result in increased generation of associated wastewaters. In some cases disposal to a sewage treatment plant may be favored but plant performance must be maintained. To assess the potential effects of such wastewaters on biological wastewater treatment, model nitrifying organisms Nitrosomonas europaea and Nitrobacter winogradskyi were exposed to simulated wastewaters containing varying levels of yttrium or europium (10, 50 and 100 ppm), and the REE extractant tributyl phosphate (TBP, at 0.1 g/L). Y and Eu additions above 10 ppm inhibited N.more » europaea activity, even when initially virtually all of the REE was insoluble. The provision of TBP together with Eu increased inhibition of nitrite production by the N. europaea, although TBP alone did not substantially alter nitrifying activity N. winogradskyi was more sensitive to the stimulated wastewaters, with even 10 ppm Eu or Y inducing significant inhibition, and a complete shutdown of nitrifying activity occurred in the presence of the TBP. To analyze the availability of REEs in aqueous solutions, REE solubility has been calculated using the previously developed MSE (Mixed-Solvent Electrolyte) thermodynamic model. The model calculations reveal a strong pH dependence of solubility, which is typically controlled by the precipitation of REE hydroxides but may also be influenced by the formation of a phosphate phase.« less

  9. Selective Inhibition of Ammonium Oxidation and Nitrification-Linked N2O Formation by Methyl Fluoride and Dimethyl Ether

    PubMed Central

    Miller, Laurence G.; Coutlakis, M. Denise; Oremland, Ronald S.; Ward, Bess B.

    1993-01-01

    Methyl fluoride (CH3F) and dimethyl ether (DME) inhibited nitrification in washed-cell suspensions of Nitrosomonas europaea and in a variety of oxygenated soils and sediments. Headspace additions of CH3F (10% [vol/vol]) and DME (25% [vol/vol]) fully inhibited NO2- and N2O production from NH4+ in incubations of N. europaea, while lower concentrations of these gases resulted in partial inhibition. Oxidation of hydroxylamine (NH2OH) by N. europaea and oxidation of NO2- by a Nitrobacter sp. were unaffected by CH3F or DME. In nitrifying soils, CH3F and DME inhibited N2O production. In field experiments with surface flux chambers and intact cores, CH3F reduced the release of N2O from soils to the atmosphere by 20- to 30-fold. Inhibition by CH3F also resulted in decreased NO3- + NO2- levels and increased NH4+ levels in soils. CH3F did not affect patterns of dissimilatory nitrate reduction to ammonia in cell suspensions of a nitrate-respiring bacterium, nor did it affect N2O metabolism in denitrifying soils. CH3F and DME will be useful in discriminating N2O production via nitrification and denitrification when both processes occur and in decoupling these processes by blocking NO2- and NO3- production. PMID:16349011

  10. Effects of simulated rare earth recycling wastewaters on biological nitrification

    SciTech Connect

    Fujita, Yoshiko; Barnes, Joni; Eslamimanesh, Ali; Lencka, Malgorzata M.; Anderko, Andrzej; Riman, Richard E.; Navrotsky, Alexandra

    2015-07-16

    Current efforts to increase domestic availability of rare-earth element (REE) supplies by recycling and expanded ore processing efforts will result in increased generation of associated wastewaters. In some cases disposal to a sewage treatment plant may be favored but plant performance must be maintained. To assess the potential effects of such wastewaters on biological wastewater treatment, model nitrifying organisms Nitrosomonas europaea and Nitrobacter winogradskyi were exposed to simulated wastewaters containing varying levels of yttrium or europium (10, 50 and 100 ppm), and the REE extractant tributyl phosphate (TBP, at 0.1 g/L). Y and Eu additions above 10 ppm inhibited N. europaea activity, even when initially virtually all of the REE was insoluble. The provision of TBP together with Eu increased inhibition of nitrite production by the N. europaea, although TBP alone did not substantially alter nitrifying activity N. winogradskyi was more sensitive to the stimulated wastewaters, with even 10 ppm Eu or Y inducing significant inhibition, and a complete shutdown of nitrifying activity occurred in the presence of the TBP. To analyze the availability of REEs in aqueous solutions, REE solubility has been calculated using the previously developed MSE (Mixed-Solvent Electrolyte) thermodynamic model. The model calculations reveal a strong pH dependence of solubility, which is typically controlled by the precipitation of REE hydroxides but may also be influenced by the formation of a phosphate phase.

  11. Selective inhibition of ammonium oxidation and nitrification-linked N2O formation by methyl fluoride and dimethyl ether

    USGS Publications Warehouse

    Miller, L.G.; Coutlakis, M.D.; Oremland, R.S.; Ward, B.B.

    1993-01-01

    Methyl fluoride (CH3F) and dimethyl ether (DME) inhibited nitrification in washed-cell suspensions of Nitrosomonas europaea and in a variety of oxygenated soils and sediments. Headspace additions of CH3F (10% [vol/vol]) and DME (25% [vol/vol]) fully inhibited NO2- and N2O production from NH4+ in incubations of N. europaea, while lower concentrations of these gases resulted in partial inhibition. Oxidation of hydroxylamine (NH2OH) by N. europaea and oxidation of NO2- by a Nitrobacter sp. were unaffected by CH3F or DME. In nitrifying soils, CH3F and DME inhibited N2O production. In field experiments with surface flux chambers and intact cores, CH3F reduced the release of N2O from soils to the atmosphere by 20- to 30-fold. Inhibition by CH3F also resulted in decreased NO3- + NO2- levels and increased NH4+ levels in soils. CH3F did not affect patterns of dissimilatory nitrate reduction to ammonia in cell suspensions of a nitrate- respiring bacterium, nor did it affect N2O metabolism in denitrifying soils. CH3F and DME will be useful in discriminating N2O production via nitrification and denitrification when both processes occur and in decoupling these processes by blocking NO2- and NO3- production.

  12. Effects of Simulated Rare Earth Recycling Wastewaters on Biological Nitrification.

    PubMed

    Fujita, Yoshiko; Barnes, Joni; Eslamimanesh, Ali; Lencka, Malgorzata M; Anderko, Andrzej; Riman, Richard E; Navrotsky, Alexandra

    2015-08-18

    Increasing rare earth element (REE) supplies by recycling and expanded ore processing will result in generation of new wastewaters. In some cases, disposal to a sewage treatment plant may be favored, but plant performance must be maintained. To assess the potential effects of such wastewaters on biological treatment, model nitrifying organisms Nitrosomonas europaea and Nitrobacter winogradskyi were exposed to simulated wastewaters containing varying levels of yttrium or europium (10, 50, and 100 ppm), and the extractant tributyl phosphate (TBP, at 0.1 g/L). Y and Eu additions at 50 and 100 ppm inhibited N. europaea, even when virtually all of the REE was insoluble. Provision of TBP with Eu increased N. europaea inhibition, although TBP alone did not substantially alter activity. For N. winogradskyi cultures, Eu or Y additions at all tested levels induced significant inhibition, and nitrification shut down completely with TBP addition. REE solubility was calculated using the previously developed MSE (Mixed-Solvent Electrolyte) thermodynamic model. The model calculations reveal a strong pH dependence of solubility, typically controlled by the precipitation of REE hydroxides but also likely affected by the formation of unknown phosphate phases, which determined aqueous concentrations experienced by the microorganisms.

  13. Hypersensitivity to pollen of Olea europaea in Israel.

    PubMed

    Geller-Bernstein, C; Arad, G; Keynan, N; Lahoz, C; Cardaba, B; Waisel, Y

    1996-05-01

    The incidence of skin-tested sensitivity to olive pollen allergens among subjects with suspected atopic respiratory allergy was investigated in various populations of Israelis. This incidence was correlated with the olive cultivars, with the abundance of trees in the patient's neighborhoods, and with the history of exposure of the studied populations to olive pollen. Positive skin reactions to olive pollen, among atopic patients of the Jewish population, is rather high where olive trees are abundant (66%), and lower (29%) where trees are scarce (P < 0.003). Sensitization was significantly lower (P < 0.003) among a population of Israeli atopic Arabs (16%), though these Arabs have lived in an olive-rich area for several generations.

  14. Sensitivity to olea Europaea pollen in different populations in Israel.

    PubMed

    Geller-Bernstein, C; Zaharan, Y; Waisel, Y

    1994-11-01

    Sensitivity to olive pollen was studied (by skin tests) in different Israeli populations suffering from respiratory allergies. The results were compared with aerobiological data, in order to correlate amount of exposure to prevalence of sensitization. It was found that in the Jewish population, sensitivity to olive pollen developed in direct proportion with the number of olive trees in the settlement: 66% where trees density is high, 29% where it is low. In the Arab population however, possibly genetically determined, the sensitization to olive pollen was low (only 14%) even though the density of trees is high.

  15. Metabolism of Nitrogen Oxides in Ammonia-Oxidizing Bacteria

    NASA Astrophysics Data System (ADS)

    Kozlowski, J.; Stein, L. Y.

    2014-12-01

    Ammonia-oxidizing bacteria (AOB) are key microorganisms in the transformation of nitrogen intermediates in most all environments. Until recently there was very little work done to elucidate the physiology of ammonia-oxidizing bacteria cultivated from variable trophic state environments. With a greater variety of ammonia-oxidizers now in pure culture the importance of comparative physiological and genomic analysis is crucial. Nearly all known physiology of ammonia-oxidizing bacteria lies within the Nitrosomonas genus with Nitrosomonas europaea strain ATCC 19718 as the model. To more broadly characterize and understand the nature of obligate ammonia chemolithotrophy and the contribution of AOB to production of nitrogen oxides, Nitrosomonas spp. and Nitrosospira spp. isolated from variable trophic states and with sequenced genomes, were utilized. Instantaneous ammonia- and hydroxylamine-oxidation kinetics as a function of oxygen and substrate concentration were measured using an oxygen micro-sensor. The pathway intermediates nitric oxide and nitrous oxide were measured in real time using substrate-specific micro-sensors to elucidate whether production of these molecules is stoichiometric with rates of substrate oxidation. Genomic inventory was compared among the strains to identify specific pathways and modules to explain physiological differences in kinetic rates and production of N-oxide intermediates as a condition of their adaptation to different ammonium concentrations. This work provides knowledge of how nitrogen metabolism is differentially controlled in AOB that are adapted to different concentrations of ammonium. Overall, this work will provide further insight into the control of ammonia oxidizing chemolithotrophy across representatives of the Nitrosomonas and Nitrosospira genus, which can then be applied to examine additional genome-sequenced AOB isolates.

  16. Abundance and diversity based on amoA genes of ammonia-oxidizing archaea and bacteria in ten wastewater treatment systems.

    PubMed

    Gao, Jingfeng; Luo, Xin; Wu, Guixia; Li, Ting; Peng, Yongzhen

    2014-04-01

    The abundance and diversity of amoA genes of ammonia-oxidizing archaea (AOA) and bacteria (AOB) were investigated in ten wastewater treatment systems (WTSs) by polymerase chain reaction (PCR), cloning, sequencing, and quantitative real-time PCR (qPCR). The ten WTSs included four full-scale municipal WTSs, three full-scale industrial WTSs, and three lab-scale WTSs. AOB were present in all the WTSs, whereas AOA were detected in nine WTSs. QPCR data showed that AOB amoA genes (4.625 × 10(4)-9.99 × 10(9) copies g(-1) sludge) outnumbered AOA amoA genes (Nitrosomonas was the most dominant species in the ten WTSs; Nitrosomonas europaea cluster was the dominant major cluster, followed by Nitrosomonas-like cluster and Nitrosomonas oligotropha cluster; and AOB species showed higher diversity than AOA species. AOA were found to be affiliated with two major clusters: Nitrososphaera cluster and Nitrosopumilus cluster. Nitrososphaera cluster was the most dominant species in different samples and distributed worldwide.

  17. Reporter Licensing.

    ERIC Educational Resources Information Center

    Henderson, Leslie C.

    This report reviews some of the efforts to license news reporters. The review summarizes court litigation concerning city and state legislation and federal efforts to screen or regulate the movements of journalists covering political news events. Highlighting the report are discussions of the United States Secret Service's role in issuing White…

  18. Ammonia-Oxidizing Bacteria in Biofilters Removing Trihalomethanes Are Related to Nitrosomonas oligotropha

    EPA Science Inventory

    Nitrifying biofilters degrading the four regulated trihalomethanes (THMs) trichloromethane (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and tribromomethane (TBM) -were analyzed for the presence and activity of ammonia-oxidizing bacteria (AOB). Biofilter perfor...

  19. International Reports.

    ERIC Educational Resources Information Center

    Tabb, Winston; Bender, David R.; Haycock, Ken; Horodyski, John

    2001-01-01

    Includes three annual reports: one from the International Federation of Library Associations and Institutions, the Special Libraries Association, and a report on innovations in Canadian libraries that discusses electronic initiatives, partnerships, books and publishing, school libraries, national issues, local challenges, and funding. (LRW)

  20. Workshop Reports

    NASA Astrophysics Data System (ADS)

    2012-04-01

    19 Workshops were held during IAU S285. 15 submitted reports of the discussions that took place, while for the remaining 4 we have reproduced the summaries that were available on our wiki prior to the Symposium.

  1. Final Report

    SciTech Connect

    DeTar, Carleton

    2012-12-10

    This document constitutes the Final Report for award DE-FC02-06ER41446 as required by the Office of Science. It summarizes accomplishments and provides copies of scientific publications with significant contribution from this award.

  2. Reportable diseases

    MedlinePlus

    ... be made in writing. Examples are gonorrhea and salmonellosis . Mandatory reporting by telephone.The provider must make ... Rocky Mountain spotted fever Rubella (including congenital ... Severe acute respiratory syndrome (SARS) Shiga toxin-producing ...

  3. Semiannual report

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This report summarizes research conducted at the Institute for Computer Applications in Science and Engineering in applied mathematics, fluid mechanics, and computer science during the period 1 Oct. 1994 - 31 Mar. 1995.

  4. Report Cyberbullying

    MedlinePlus

    ... Policies & Laws | Español Search Stopbullying.gov WHAT IS BULLYING Definition The Roles Kids Play Other Types of Aggressive Behavior CYBER BULLYING What is Cyberbullying? Prevent Cyberbullying Report Cyberbullying WHO ...

  5. Final Report

    SciTech Connect

    Thomas D. Sharkey

    2005-02-07

    This report describes basic science studies of conversion of starch to sucrose in plant leaves. The importance of maltose is described. The studies proved that hydrolysis of the starch is more important than phosphorolysis.

  6. Technology Report

    NASA Technical Reports Server (NTRS)

    Repucci, George

    1996-01-01

    This is the fourth report of a series of semi-annual reports that describe the technology areas being advanced under this contract and the progress achieved to date. The most significant technical event this period was the successful completion of the Lewis spacecraft in 2 years (contract award date was June 1994). In August of 1996 we held a program-wide Technology Workshop which covered all aspects of the Lewis payload. A copy of the Workshop proceedings is attached.

  7. PHENIX REPORTS

    SciTech Connect

    TIMOTHY C. THOMPSON - HYTEC, INC.

    1998-12-10

    This report contains individual progress reports for the months of December 1997 through May 1998 on the Phenix program at Hytec. Topics include the Phenix muon detector chamber flow analysis; the Phenix Muon detector deformation and motion/tolerance study of Stations 1, 2, and 3; finite element mount/electron shield structural analysis; South Station 3 muon detector deformation analysis; and Station 1 muon detector panel assembly and fabrication sequences.

  8. Japan Report.

    DTIC Science & Technology

    1987-02-03

    10503« JPRS-JAR-87-001 3 FEBRUARY 1987 Japan Report 19980629 058 FBIS FOREIGN BROADCAST INFORMATION SERVICE BTIO QUALITY INSPECTED 6... JAPAN REPORT CONTENTS POLITICAL AND SOCIOLOGICAL Impact of Miyazawa’s Appointment as Finance Minister (Kenzo Uchida, et al.; ZAIKAI TEMBO, Oct 86...Direct U.S. Investment Discussed (Akio Morita, et? al.; KEIDANREN GEPPO, Sep 86) 30 Japan -PRC Trade Expansion Council Officially Inaugurated

  9. Health Reports.

    DTIC Science & Technology

    1992-12-01

    Mar. 18, 1992, GAO/IMTEC-92-41). Testimony on same topic (Mar. 18, 1992, GAO/T-IMTEU-92-1 I). Cross Design Synthesis : A New Strategy for Medical... Synthesis : A New Strategy for Medical Effectiveness Research (Report, Mar. 17, 1992, GAO/PEMD-92-18). Medical Technology: Quality Assurance Needs Stronger... Methadone Maintenance: Some Treatment Programs Are Not Effective; Greater Federal Oversight Needed (Testimony, Mar. 23, 1990, GA(Orr-IIRI)-90-19). Report on

  10. Using Pure Cultures to Define the Site Preference of Nitrous Oxide Produced by Microbial Nitrification and Denitrification

    NASA Astrophysics Data System (ADS)

    Sutka, R. L.; Breznak, J. A.; Ostrom, N. E.; Ostrom, P. H.; Gandhi, H.

    2004-12-01

    Defining the site preference of nitrous oxide (N2O) produced in pure culture studies is crucial to interpreting field data. We have previously demonstrated that the intramolecular distribution of nitrogen isotopes (isotopomers) can be used to differentiate N2O produced by nitrifier denitrification and nitrification in cultures of Nitrosomonas europaea. Here, we have expanded on our initial results and evaluated the isotopomeric composition of N2O produced during nitrification and nitrifier denitrification with cultures of Nitrosospira multiformis. In addition, we have analyzed N2O produced during methanotrophic nitrification, denitrification, and fungal denitrification. To evaluate N2O production during nitrification and nitrifier denitrification, we compared the site preference of N2O formed as a result of nitrite reduction and hydroxylamine oxidation with Nitrosomonas europaea and Nitrosospira multiformis. The average site preference of N2O produced by hydroxylamine oxidation was similar for Nitrosomonas europaea (33.0 ± 3.5 ‰ ) and Nitrosospira multiformis (33.1 ± 4.2 ‰ ). Nitrous oxide produced by nitrifier-denitrification by Nitrosomonas europaea and Nitrosospira multiformis had a similar site preference of - 1.4 ± 4.4 ‰ and - 1.1 ± 2.6 ‰ respectively. The results indicate that it is possible to differentiate between N2O produced by nitrite reduction and hydroxylamine oxidation by ammonia oxidizing bacteria. Methanotrophic nitrification was evaluated by analyzing the N2O produced during hydroxylamine oxidation in concentrated cell suspensions of two methane oxidizing bacteria. The site preference of N2O produced by the two methane oxidizers, Methylococcus capsulatus Bath and Methylosinus trichosporium was 31.8 ± 4.7 ‰ and 33.0 ± 4.5 ‰ respectively. The results indicate that a site preference of 33 ‰ is applicable for nitrification regardless of whether a methane oxidizer or ammonia oxidizer is involved in the reaction. To determine the site

  11. Production of NO and N2O by soil nitrifying bacteria

    NASA Technical Reports Server (NTRS)

    Lipschultz, F.; Wofsy, S. C.; Mcelroy, M. B.; Zafiriou, O. C.; Valois, F. W.; Watson, S. W.

    1981-01-01

    The composition of the atmosphere is influenced both directly and indirectly by biological activity. Evidence is presented here to suggest that nitrification in soil is a potentially significant source of both NO and N2O. Between 0.3 and 10% of the ammonium oxidized by cultures of the soil bacterium Nitrosomonas europaea is converted to these gases. The global source for NO associated with nitrification could be as large as 15,000,000 tonnes N/yr, with a source for N2O of 5,000,000-10,000,000 tonnes N/yr. Nitric oxide has a key role in tropospheric chemistry, participating in a complex set of reactions regulating OH and O3. Nitrous oxide is a dominant source of stratospheric NO and has a significant influence on climate.

  12. Production of NO and N2O by soil nitrifying bacteria

    NASA Astrophysics Data System (ADS)

    Lipschultz, F.; Wofsy, S. C.; McElroy, M. B.; Zafiriou, O. C.; Valois, F. W.; Watson, S. W.

    1981-12-01

    The composition of the atmosphere is influenced both directly and indirectly by biological activity. Evidence is presented here to suggest that nitrification in soil is a potentially significant source of both NO and N2O. Between 0.3 and 10% of the ammonium oxidized by cultures of the soil bacterium Nitrosomonas europaea is converted to these gases. The global source for NO associated with nitrification could be as large as 15,000,000 tonnes N/yr, with a source for N2O of 5,000,000-10,000,000 tonnes N/yr. Nitric oxide has a key role in tropospheric chemistry, participating in a complex set of reactions regulating OH and O3. Nitrous oxide is a dominant source of stratospheric NO and has a significant influence on climate.

  13. Removal of hydrogen sulfide and ammonia from gas mixtures by co-immobilized cells using a new configuration of two biotrickling filters.

    PubMed

    Ramirez, M; Gómez, J M; Aroca, G; Cantero, D

    2009-01-01

    The simultaneous removal of H(2)S and NH(3) was investigated using two biotrickling filters packed with polyurethane foam cubes. One biotrickling filter was inoculated with Thiobacillus thioparus ATCC 23645 for the removal of H(2)S (BTT) and the other filter with Nitrosomonas europaea ATCC 19718 for the removal of NH(3) (BNE). Three different configurations were studied by modification of the gas line and recirculation medium line. The best results were obtained with the BNE biotrickling filter after the co-immobilization of the two bacteria. A removal efficiency of 100% for 230 ppmv of NH(3) and 129 ppmv of H(2)S was reached at an EBRT of 60 seconds. The results obtained show that it is possible to co-immobilize both microorganisms using the same recirculation medium and remove successfully H(2)S and NH(3) from a gas mixture.

  14. Effects of dissolved oxygen and pH on nitrous oxide production rates in autotrophic partial nitrification granules.

    PubMed

    Rathnayake, Rathnayake M L D; Oshiki, Mamoru; Ishii, Satoshi; Segawa, Takahiro; Satoh, Hisashi; Okabe, Satoshi

    2015-12-01

    The effects of dissolved oxygen (DO) and pH on nitrous oxide (N2O) production rates and pathways in autotrophic partial nitrification (PN) granules were investigated at the granular level. N2O was primarily produced by betaproteobacterial ammonia-oxidizing bacteria, mainly Nitrosomonas europaea, in the oxic surface layer (<200μm) of the autotrophic PN granules. N2O production increased with increasing bulk DO concentration owing to activation of the ammonia (i.e., hydroxylamine) oxidation in this layer. The highest N2O emissions were observed at pH 7.5, although the ammonia oxidation rate was unchanged between pH 6.5 and 8.5. Overall, the results of this study suggest that in situ analyses of PN granules are essential to gaining insight into N2O emission mechanisms in a granule.

  15. Tropospheric sources of NO(x) - Lightning and biology

    NASA Astrophysics Data System (ADS)

    Levine, J. S.; Augustsson, T. R.; Anderson, I. C.; Hoell, J. M., Jr.; Brewer, D. A.

    Laboratory tests were performed to quantify the expected NO(x) production by lightning and biological processes. Attention was focused on energy deposition by lightning and the oxygen partial pressure of soil, and one-dimensional photochemical models were defined for the tropospheric distributions of NO and HNO3 for various NO source strengths. The Lightning Facility data were compared with air samples of N2O production gathered during over 2 yr of flights through storms. Soil NO(x) productions were studied in terms of nitrification processes involving Nitrosomonas europaea and Alcaligenes faecalis bacteria, which change ammonium to nitrite and release NO and N2O as byproducts. The results indicate that atmospheric NO(x) is generated at two tropospheric levels, with lightning and soil bacteria being significant contributors.

  16. Tropospheric sources of NO(x) - Lightning and biology

    NASA Technical Reports Server (NTRS)

    Levine, J. S.; Augustsson, T. R.; Anderson, I. C.; Hoell, J. M., Jr.; Brewer, D. A.

    1984-01-01

    Laboratory tests were performed to quantify the expected NO(x) production by lightning and biological processes. Attention was focused on energy deposition by lightning and the oxygen partial pressure of soil, and one-dimensional photochemical models were defined for the tropospheric distributions of NO and HNO3 for various NO source strengths. The Lightning Facility data were compared with air samples of N2O production gathered during over 2 yr of flights through storms. Soil NO(x) productions were studied in terms of nitrification processes involving Nitrosomonas europaea and Alcaligenes faecalis bacteria, which change ammonium to nitrite and release NO and N2O as byproducts. The results indicate that atmospheric NO(x) is generated at two tropospheric levels, with lightning and soil bacteria being significant contributors.

  17. Autecological Study of the Chemoautotroph Nitrobacter by Immunofluorescence

    PubMed Central

    Fliermans, C. B.; Bohlool, B. B.; Schmidt, E. L.

    1974-01-01

    Fluorescent antibodies (FA) prepared for Nitrobacter agilis and N. winogradskyi were highly reactive in homologous staining. Low-level cross-reactions between the two species were removed by adsorption. All 15 pure-culture isolates of Nitrobacter tested reacted strongly with either N. agilis FA or N. winogradskyi FA. All pure-culture isolates from soils were determined to be N. winogradskyi; those from Mammoth Cave sediments and a cattle waste oxidation ditch were N. agilis. No cross-reaction was found in extensive tests that included five isolates of Nitrosomonas europaea and 668 heterotrophic aerobic and anaerobic bacteria isolated from soil, sewage, and cave sites. The FA preparations were used to detect Nitrobacter species in Mammoth Cave sediments, in a cattle waste oxidation ditch, and in surface waters and sediments of a river and to observe that N. winogradskyi can outgrow N. agilis in enrichment culture. Images PMID:4589121

  18. Purification and some properties of cytochrome c-552 from an extreme thermophile, Thermus thermophilus HB8.

    PubMed

    Hon-Nami, K; Oshima, T

    1977-09-01

    A c-type cytochrome, cytochrome c-552, from a soluble fraction of an extreme thermophile, Thermus thermophilus HB8, was highly purified and its properties investigated. The absorption peaks were at 552, 522, and 417 nm in the reduced form, and at 408 nm in the oxidized form. The isoelectric point was at PH 10.8, the midpoint redox potential was about +0.23 V, and the molecular weight was about 15,000. The cytochrome c-552 was highly thermoresistant. The cytochrome reacted rapidly with pseudomonas aeruginosa nitrite reductase [EC 1.9.3.2], but slowly with bovine cytochrome oxidase [EC 1.9.3.1], yeast cytochrome c peroxidase [EC 1.11.1.5], or Nitrosomonas europaea hydroxylamine-cytochrome c reductase [EC 1.7.3.4].

  19. A potentiometric flow biosensor based on ammonia-oxidizing bacteria for the detection of toxicity in water.

    PubMed

    Zhang, Qianyu; Ding, Jiawang; Kou, Lijuan; Qin, Wei

    2013-05-24

    A flow biosensor for the detection of toxicity in water using the ammonia-oxidizing bacterium (AOB) Nitrosomonas europaea as a bioreceptor and a polymeric membrane ammonium-selective electrode as a transducer is described. The system is based on the inhibition effects of toxicants on the activity of AOB, which can be evaluated by measuring the ammonium consumption rates with the ammonium-selective membrane electrode. The AOB cells are immobilized on polyethersulfone membranes packed in a holder, while the membrane electrode is placed downstream in the flow cell. Two specific inhibitors of the ammonia oxidation-allylthiourea and thioacetamide-have been tested. The IC50 values defined as the concentration of an inhibitor causing a 50% reduction in the ammonia oxidation activity have been measured as 0.17 μM and 0.46 μM for allylthiourea and thioacetamide, respectively. The proposed sensor offers advantages of simplicity, speed and high sensitivity for measuring toxicity in water.

  20. Nitrification Inhibitors from the root tissues of Brachiaria humidicola, a tropical grass.

    PubMed

    Gopalakrishnan, Subramaniam; Subbarao, Guntur V; Nakahara, Kazuhiko; Yoshihashi, Tadashi; Ito, Osamu; Maeda, Ikuko; Ono, Hiroshi; Yoshida, Mitsuru

    2007-02-21

    Nitrification inhibitory activity was found in root tissue extracts of Brachiaria humidicola, a tropical pasture grass. Two active inhibitory compounds were isolated by activity-guided fractionation, using recombinant Nitrosomonas europaea containing luxAB genes derived from the bioluminescent marine gram-negative bacterium Vibrio harveyi. The compounds were identified as methyl-p-coumarate and methyl ferulate, respectively. Their nitrification inhibitory properties were confirmed in chemically synthesized preparations of each. The IC50 values of chemically synthesized preparations were 19.5 and 4.4 microM, respectively. The ethyl, propyl, and butyl esters of p-coumaric and ferulic acids inhibited nitrification, whereas the free acid forms did not show inhibitory activity.

  1. Expression, and Molecular and Enzymatic Characterization of Cu-Containing Nitrite Reductase from a Marine Ammonia-Oxidizing Gammaproteobacterium, Nitrosococcus oceani

    PubMed Central

    Kondo, Keitaro; Yoshimatsu, Katsuhiko; Fujiwara, Taketomo

    2012-01-01

    Ammonia-oxidizing bacteria (AOB) remove intracellular nitrite to prevent its toxicity by a nitrifier denitrification pathway involving two denitrifying enzymes, nitrite reductase and nitric oxide reductase. Here, a Cu-containing nitrite reductase from Nitrosococcus oceani strain NS58, a gammaproteobacterial marine AOB, was expressed in Escherichia coli and purified to homogeneity. Sequence homology analysis indicated that the nitrite reductase from N. oceani was phylogenetically closer to its counterparts from denitrifying bacteria than that of the betaproteobacterium Nitrosomonas europaea. The recombinant enzyme was a homotrimer of a 32 kDa subunit molecule. The enzyme was green in the oxidized state with absorption peaks at 455 nm and 575 nm. EPR spectroscopy indicated the presence of type 2 Cu. Molecular activities and the affinity constant for the nitrite were determined to be 1.6×103 s−1 and 52 μM, respectively. PMID:22641151

  2. Suicidal inactivation and labelling of ammonia mono-oxygenase by acetylene.

    PubMed Central

    Hyman, M R; Wood, P M

    1985-01-01

    Acetylene brings about a progressive inactivation of ammonia mono-oxygenase, the ammonia-oxidizing enzyme in Nitrosomonas europaea. High NH4+ ion concentrations were protective. The inactivation followed first-order kinetics, with a rate constant of 1.5 min-1 at saturating concentrations of acetylene. If acetylene was added in the absence of O2, the cells remained active until O2 was re-introduced. A protective effect was also demonstrated with thiourea, a reversible non-competitive inhibitor of ammonia oxidation. Incubation of cells with [14C]acetylene was found to cause labelling of a single membrane polypeptide. This ran on dodecyl sulphate/polyacrylamide-gel electrophoresis with an Mr value of 28 000. It is concluded that acetylene is a suicide substrate for the mono-oxygenase. The labelling experiment provides the first identification of a constituent polypeptide of ammonia mono-oxygenase. Images Fig. 4. PMID:4004794

  3. Microbial community structure and occurrence of diverse autotrophic ammonium oxidizing microorganisms in the anammox process.

    PubMed

    Bae, H; Chung, Y-C; Jung, J-Y

    2010-01-01

    The enrichment of anaerobic ammonium oxidizing (anammox) bacteria using an upflow anaerobic sludge bioreactor was successfully conducted for 400 days of continuous operation. The bacterial community structure of anammox bioreactor included Proteobacteria (42%), Chloroflexi (22%), Planctomycetes (20%), Chlorobi (7%), Bacteroidetes (5%), Acidobacteria (2%), and Actinobacteria (2%). All clones of Planctomycetes were affiliated with the anammox bacteria, Planctomycete KSU-1 (AB057453). The presence and diversity of ammonia oxidizing bacteria (AOB) and archaea (AOA) were identified by terminal restriction fragment length polymorphism (T-RFLP) based on the amoA gene sequences. The AOB in anammox bioreactor were affiliated with the Nitrosomonas europaea cluster. The T-RFLP result of AOA showed the diverse microbial community structure of AOA with three terminal restriction fragments (T-RFs).

  4. Lidar Report

    SciTech Connect

    Wollpert.

    2009-04-01

    This report provides an overview of the LiDAR acquisition methodology employed by Woolpert on the 2009 USDA - Savannah River LiDAR Site Project. LiDAR system parameters and flight and equipment information is also included. The LiDAR data acquisition was executed in ten sessions from February 21 through final reflights on March 2, 2009; using two Leica ALS50-II 150kHz Multi-pulse enabled LiDAR Systems. Specific details about the ALS50-II systems are included in Section 4 of this report.

  5. Russia report

    NASA Astrophysics Data System (ADS)

    Along with cementing the joint Shuttle-Mir Program in late June with a $400 million contract, the U.S. and Russia signed a deal to team up on global environmental issues. Under the agreement, U.S. and Russian scientists will establish modern facilities for petroleum research, including advanced geographic systems technology, petroleum geochemistry, and seismic processing to help Russia transition to a “market” economy, Interior Secreary Bruce Babbitt reports. The program, to be funded by the U.S. Agency for International Development, will produce maps, technical reports, and other data for investment decisions.

  6. Japan Report.

    DTIC Science & Technology

    1985-04-30

    172068 JPRS-JAR-85-0 1 0 3 0 April 198 5 Japan Report 19980722 116 »TIC QUALITY SfSPECTED 3 FBIS FOREIGN BROADCAST INFORMATION SERVICE...85-010 30 April 19 85 JAPAN REPORT CONTENTS POLITICAL AND SOCIOLOGICAL Break Up of Tanaka-Nakasone Alliance Anticipated (Taro Maki; SEKAI, Jan 85...minister. It became "When I was prime minister, Japan was isolated in international society," and although at the U.S.- Japan summit talks President Reagan

  7. Japan Report.

    DTIC Science & Technology

    2007-11-02

    034079 JPRS-JAR-85-005 1 9 February 1 985 Japan Report A Appro-mi for pwMe \\ɘ!fc W [OTIC QUALITY IfSPIS CTED 9 FBIS FOREIGN...Virginia 22201. JPRS-JAR-85-005 19 February 1985 JAPAN REPORT CONTENTS POLITICAL AND SOCIOLOGICAL ’Crisis-Management Set-Up’ Critiqued (Koichiro...Output Jumps 11.2 Percent in 1984 (KYODO, 29 Jan 85) 43 Japan , U.S. Aircraft Makers To Cooperate (KYODO, 25 Jan 85) 45 Japan Seeks End to Auto

  8. Special Reports.

    ERIC Educational Resources Information Center

    Peters, Thomas A.; Hill, Janet Swan; Haycock, Ken; Valauskas, Edward J.

    2001-01-01

    These four reports discuss the electronic publishing industry, including dedicated reading devices for electronic books, reader software, Web-based commercial e-book libraries, intellectual property issues, and standards; outsourcing practices in libraries; the use of Internet filters in North American schools; and recent developments and future…

  9. International Reports.

    ERIC Educational Resources Information Center

    Anderson, Nancy D.; And Others

    1994-01-01

    Three reports discuss the International Federation of Library Associations and Institutions; the Frankfurt Book Fair, focusing on electronics; and Canadian library trends, including resource sharing, technology projects, information policy, censorship, services for persons with disabilities, construction projects, and library education and…

  10. Special Reports.

    ERIC Educational Resources Information Center

    Young, Peter R.; And Others

    1994-01-01

    Includes six special reports: "Libraries and the National Information Infrastructure" (Peter R. Young and Jane Williams); "Library Cooperation and Networking" (JoAn Segal); "Mexican Information Resources in Electronic Format" (Shirley Ainsworth); "The International Role of U.S. Librarians" (Hannelore B.…

  11. Special Reports.

    ERIC Educational Resources Information Center

    Wiant, Sarah K.; Lynch, Clifford; Nevins, Kate; Juergens, Bonnie

    1998-01-01

    Contains three special reports: developments in copyright law, 1997 (World Intellectual Property Organization (WIPO) legislation, Ashcroft Bill, No Electronic Theft Act, database protection, Conference on Fair Use (CONFU), judicial decisions, principles for licensing electronic resources, and Uniform Commercial Code Article 2B); Internet2 and the…

  12. FROGS report

    NASA Astrophysics Data System (ADS)

    FROGS Reports present information on current research relevant to felsic magmatism, including commentaries on problems of current interest. Please contact Calvin Miller, Geology, 6028B, Vanderbilt University, Nashville, TN 37235; tel. 615-322-2986 about your own research, conferences, and ideas for stimulating commentaries.

  13. World Report.

    ERIC Educational Resources Information Center

    Ceres, 1978

    1978-01-01

    Presents a report that deals with several topics from different parts of the world. A system for creating more meaningful maps, the recycling of organic wastes in agriculture in China, and producing pigs and poultry without pollution problems are among the topics presented. (HM)

  14. Special Report

    PubMed Central

    Likosky, Donald S.; Baker, Robert A.; Dickinson, Timothy A.; FitzGerald, Daniel J.; De Somer, M. Filip; Groom, Robert C.; Fitzgerald, David; Shann, Kenneth G.; Poullis, Michael; Spiess, Bruce D.; Jabr, Karim; Lucas, Mark T.; Ferguson, James D.; Bronson, Shahna L.

    2015-01-01

    Abstract: Gaps remain in our understanding of the contribution of bypass-related practices associated with red blood cell (RBC) transfusions after cardiac surgery. Variability exists in the reporting of bypass-related practices in the peer-reviewed literature. In an effort to create uniformity in reporting, a draft statement outlining proposed minimal criteria for reporting cardiopulmonary bypass (CPB)-related contributions (i.e., RBC data collection/documentation, clinical considerations for transfusions, equipment details, and clinical endpoints) was presented in conjunction with the American Society of ExtraCorporeal Technology’s (AmSECT’s) 2014 Quality and Outcomes Meeting (Baltimore, MD). Based on presentations and feedback from the conference, coauthors (n = 14) developed and subsequently voted on each proposed data element. Data elements receiving a total of ≤4 votes were dropped from further consideration, 5–9 votes were considered as “Recommended,” and elements receiving ≥10 votes were considered as “Mandatory.” A total of 52 elements were classified as mandatory, 16 recommended, and 14 dropped. There are 8 mandatory data elements for RBC data collection/documentation, 24 for clinical considerations for transfusions, 13 for equipment details, and 7 for clinical endpoints. We present 52 mandatory data elements reflecting CPB-related contributions to RBC transfusions. Consistency of such reporting would offer our community an increased opportunity to shed light on the relationship between intra-operative practices and RBC transfusions. PMID:26405355

  15. Country Reports.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France). Environmental Education Section.

    The reports from five countries participating at a seminar on teacher training in environmental education for Asia are compiled in this document. The objectives of the seminar were: (1) to familiarize teacher educators with the contents of the series of teacher training modules in environmental education prepared by the International Environmental…

  16. AVA Report.

    ERIC Educational Resources Information Center

    American Vocational Association, Inc., Washington, DC.

    This report contains the major presentations made at the American Vocational Association Convention, and also summarizes the group discussions which included conclusions and recommendations of the groups. Opening remarks were made by Mr. Lowell A. Burkett, with presentations including: (1) "Manpower Programs and Postsecondary Educational…

  17. Activity report

    SciTech Connect

    Yu, S W

    2008-08-11

    This report is aimed to show the author's activities to support the LDRD. The title is 'Investigation of the Double-C Behavior in the Pu-Ga Time-Temperature-Transformation Diagram' The sections are: (1) Sample Holder Test; (2) Calculation of x-ray diffraction patterns; (3) Literature search and preparing publications; (4) Tasks Required for APS Experiments; and (5) Communications.

  18. Complete Genome Sequence of Nitrosospira multiformis, an Ammonia-Oxidizing Bacterium from the Soil Environment▿ †

    PubMed Central

    Norton, Jeanette M.; Klotz, Martin G.; Stein, Lisa Y.; Arp, Daniel J.; Bottomley, Peter J.; Chain, Patrick S. G.; Hauser, Loren J.; Land, Miriam L.; Larimer, Frank W.; Shin, Maria W.; Starkenburg, Shawn R.

    2008-01-01

    The complete genome of the ammonia-oxidizing bacterium Nitrosospira multiformis (ATCC 25196T) consists of a circular chromosome and three small plasmids totaling 3,234,309 bp and encoding 2,827 putative proteins. Of the 2,827 putative proteins, 2,026 proteins have predicted functions and 801 are without conserved functional domains, yet 747 of these have similarity to other predicted proteins in databases. Gene homologs from Nitrosomonas europaea and Nitrosomonas eutropha were the best match for 42% of the predicted genes in N. multiformis. The N. multiformis genome contains three nearly identical copies of amo and hao gene clusters as large repeats. The features of N. multiformis that distinguish it from N. europaea include the presence of gene clusters encoding urease and hydrogenase, a ribulose-bisphosphate carboxylase/oxygenase-encoding operon of distinctive structure and phylogeny, and a relatively small complement of genes related to Fe acquisition. Systems for synthesis of a pyoverdine-like siderophore and for acyl-homoserine lactone were unique to N. multiformis among the sequenced genomes of ammonia-oxidizing bacteria. Gene clusters encoding proteins associated with outer membrane and cell envelope functions, including transporters, porins, exopolysaccharide synthesis, capsule formation, and protein sorting/export, were abundant. Numerous sensory transduction and response regulator gene systems directed toward sensing of the extracellular environment are described. Gene clusters for glycogen, polyphosphate, and cyanophycin storage and utilization were identified, providing mechanisms for meeting energy requirements under substrate-limited conditions. The genome of N. multiformis encodes the core pathways for chemolithoautotrophy along with adaptations for surface growth and survival in soil environments. PMID:18390676

  19. Clinical Report

    PubMed Central

    Stevens, Lindsay; Tartaglia, Nicole; Hagerman, Randi; Riley, Karen

    2013-01-01

    A case of a 14-year-old boy with both fragile X syndrome and Down syndrome is described. This is the third reported case of a patient with fragile X syndrome plus Down syndrome and the first reported case in a male. Facial features are generally consistent with Down syndrome; however, a prominent forehead and jaw and maccroorchidism were consistent with fragile X syndrome. Joint laxity is also present, which is consistent with both disorders. Cognitive impairment is more significant than in his siblings with fragile X syndrome, and he meets criteria for autistic disorder. Ongoing behavioral dysregulation has been significant, leading to disruption of home and school environments despite many attempted psychopharmacologic and behavioral strategies and a supportive family. Identification and treatment of underlying medical problems (esophagitis) led to improvements in sleep and behavior. We emphasize discussion of challenges in his behavioral management and present a collaborative approach to behavioral management. PMID:20453578

  20. Final Report

    SciTech Connect

    Marchant, Gary E.

    2013-04-23

    This is the final report of a two year project entitled "Governing Nanotechnology Risks and Benefits in the Transition to Regulation: Innovative Public and Private Approaches." This project examined the role of new governance or "soft law" mechanisms such as codes of conduct, voluntary programs and partnership agreements to manage the risks of emerging technologies such as nanotechnology. A series of published or in publication papers and book chapters are attached.

  1. Final Report

    SciTech Connect

    R. Paul Drake

    2001-11-30

    This final report describes work involving 22 investigators from 11 institutions to explore the dynamics present in supernova explosions by means of experiments on the Omega laser. The specific experiments emphasized involved the unstable expansion of a spherical capsule and the coupling of perturbations at a first interface to a second interface by means of a strong shock. Both effects are present in supernovae. The experiments were performed at Omega and the computer simulations were undertaken at several institutions. B139

  2. CRD Report

    SciTech Connect

    Wang, Ucilia

    2007-12-18

    This report has the following articles: (1) Deconstructing Microbes--metagenomic research on bugs in termites relies on new data analysis tools; (2) Popular Science--a nanomaterial research paper in Nano Letters drew strong interest from the scientific community; (3) Direct Approach--researchers employ an algorithm to solve an energy-reduction issue essential in describing complex physical system; and (4) SciDAC Special--A science journal features research on petascale enabling technologies.

  3. Final Report

    SciTech Connect

    Stinis, Panos

    2016-08-07

    This is the final report for the work conducted at the University of Minnesota (during the period 12/01/12-09/18/14) by PI Panos Stinis as part of the "Collaboratory on Mathematics for Mesoscopic Modeling of Materials" (CM4). CM4 is a multi-institution DOE-funded project whose aim is to conduct basic and applied research in the emerging field of mesoscopic modeling of materials.

  4. Effect of pH and HNO2 concentration on the activity of ammonia-oxidizing bacteria in a partial nitritation reactor.

    PubMed

    Claros, J; Jiménez, E; Aguado, D; Ferrer, J; Seco, A; Serralta, J

    2013-01-01

    Ammonia-oxidizing bacteria (AOB) are very sensitive to environmental conditions and wastewater treatment plant operational parameters. One of the most important factors affecting their activity is pH. Its effect is associated with: NH3/NH4(+) and HNO2/NO2(-) chemical equilibriums and biological reaction rates. The aim of this study was to quantify and model the effect of pH and free nitrous acid (FNA) concentration on the activity of AOB present in a lab-scale partial nitritation reactor. For this purpose, two sets of batch experiments were carried out using biomass from this reactor. Fluorescent in situ hybridization analysis showed that Nitrosomona eutropha and Nitrosomona europaea species were dominant in the partial nitritation reactor (>94%). The experimental results showed that FNA inhibits the AOB activity. This inhibition was properly modelled by the non-competitive inhibition function and the half inhibition constant value was determined as 1.32 mg HNO2-N L(-1). The optimal pH for these AOB was found to be in the range 7.4-7.8. The pH inhibitory effect was stronger at high pH values than at low pH values. Therefore, an asymmetric inhibition function was proposed to represent the pH effect on these bacteria. A combination of two sigmoidal functions was able to reproduce the experimental results obtained.

  5. Analysis of ammonia-oxidizing bacteria from hypersaline Mono Lake, California, on the basis of 16S rRNA sequences.

    PubMed

    Ward, B B; Martino, D P; Diaz, M C; Joye, S B

    2000-07-01

    Ammonia-oxidizing bacteria were detected by PCR amplification of DNA extracted from filtered water samples throughout the water column of Mono Lake, California. Ammonia-oxidizing members of the beta subdivision of the division Proteobacteria (beta-subdivision Proteobacteria) were detected using previously characterized PCR primers; target sequences were detected by direct amplification in both surface water and below the chemocline. Denaturing gradient gel electrophoresis analysis indicated the presence of at least four different beta-subdivision ammonia oxidizers in some samples. Subsequent sequencing of amplified 16S rDNA fragments verified the presence of sequences very similar to those of cultured Nitrosomonas strains. Two separate analyses, carried out under different conditions (different reagents, locations, PCR machines, sequencers, etc.), 2 years apart, detected similar ranges of sequence diversity in these samples. It seems likely that the physiological diversity of nitrifiers exceeds the diversity of their ribosomal sequences and that these sequences represent members of the Nitrosomonas europaea group that are acclimated to alkaline, high-salinity environments. Primers specific for Nitrosococcus oceanus, a marine ammonia-oxidizing bacterium in the gamma subdivision of the Proteobacteria, did not amplify target from any samples.

  6. Impact of food to microorganism (F/M) ratio and colloidal chemical oxygen demand on nitrification performance of a full-scale membrane bioreactor treating thin film transistor liquid crystal display wastewater.

    PubMed

    Wu, Yi-Ju; Whang, Liang-Ming; Chang, Ming-Yu; Fukushima, Toshikazu; Lee, Ya-Chin; Cheng, Sheng-Shung; Hsu, Shu-Fu; Chang, Cheng-Huey; Shen, Wason; Yang, Charn-Yi; Fu, Ryan; Tsai, Tsair-Yuan

    2013-08-01

    This study investigated impact of food to microorganism (F/M) ratio and colloidal chemical oxygen demand (COD) on nitrification performance in one full-scale membrane bioreactor (MBR) treating monoethanolamine (MEA)/dimethyl sulfoxide (DMSO)-containing thin film transistor liquid crystal display (TFT-LCD) wastewater. Poor nitrification was observed under high organic loading and high colloidal COD conditions, suggesting that high F/M ratio and colloidal COD situations should be avoided to minimize their negative impacts on nitrification. According to the nonmetric multidimensional scaling (NMS) statistical analyses on terminal restriction fragment length polymorphism (T-RFLP) results of ammonia monooxygenase (amoA) gene, the occurrence of Nitrosomonas oligotropha-like ammonia oxidizing bacteria (AOB) was positively related to successful nitrification in the MBR systems, while Nitrosomonas europaea-like AOB was positively linked to nitrification rate, which can be attributed to the high influent total nitrogen condition. Furthermore, Nitrobacter- and Nitrospira-like nitrite oxidizing bacteria (NOB) were both abundant in the MBR systems, but the continuously low nitrite environment is likely to promote the growth of Nitrospira-like NOB.

  7. Effects of high organic load on amoA and nirS gene diversity of an intermittently aerated and fed membrane bioreactor treating landfill leachate.

    PubMed

    Remmas, Nikolaos; Melidis, Paraschos; Katsioupi, Efthymia; Ntougias, Spyridon

    2016-11-01

    The effects of external carbon source addition on the nitrification and denitrification process were investigated in an intermittently aerated and fed membrane bioreactor treating landfill leachate by recording system performance, and amoA and nirS diversity dynamics using pyrosequencing. By adding 950mg/L glycerol, denitrification was optimized, resulting in total nitrogen removal efficiency of 81.0±2.4%. Under these conditions, amoA diversity was dominated by genotypes related to Nitrosomonas europaea, while increase in leachate's content and in glycerol addition by 50% led to irreversible inhibition of nitrification and enhanced ammonia accumulation, causing a severe suppression of Nitrosomonas and an increase in the relative abundance of Nitrosospira. However, this increase not only affected ammonia oxidizers, but also caused a massive shift in denitrifying community structure, resulting in the suppression of Arenimonas metalli-, Candidatus Accumulibacter- and Sulfuritalea hydrogenivorans-nirS related genotypes and the predominance of nirS-associated with Acidovorax and Thaurea sp.

  8. Dissimilatory Nitrite Reductase Genes from Autotrophic Ammonia-Oxidizing Bacteria

    PubMed Central

    Casciotti, Karen L.; Ward, Bess B.

    2001-01-01

    The presence of a copper-containing dissimilatory nitrite reductase gene (nirK) was discovered in several isolates of β-subdivision ammonia-oxidizing bacteria using PCR and DNA sequencing. PCR primers Cunir3 and Cunir4 were designed based on published nirK sequences from denitrifying bacteria and used to amplify a 540-bp fragment of the nirK gene from Nitrosomonas marina and five additional isolates of ammonia-oxidizing bacteria. Amplification products of the expected size were cloned and sequenced. Alignment of the nucleic acid and deduced amino acid (AA) sequences shows significant similarity (62 to 75% DNA, 58 to 76% AA) between nitrite reductases present in these nitrifiers and the copper-containing nitrite reductase found in classic heterotrophic denitrifiers. While the presence of a nitrite reductase in Nitrosomonas europaea is known from early biochemical work, preliminary sequence data from its genome indicate a rather low similarity to the denitrifier nirKs. Phylogenetic analysis of the partial nitrifier nirK sequences indicates that the topology of the nirK tree corresponds to the 16S rRNA and amoA trees. While the role of nitrite reduction in the metabolism of nitrifying bacteria is still uncertain, these data show that the nirK gene is present in closely related nitrifying isolates from many oceanographic regions and suggest that nirK sequences retrieved from the environment may include sequences from ammonia-oxidizing bacteria. PMID:11319103

  9. Abundance and diversity of ammonia-oxidizing bacteria in relation to ammonium in a chinese shallow eutrophic urban lake

    PubMed Central

    Qiu, Shanlian; Chen, Guoyuan; Zhou, Yiyong

    2010-01-01

    The measures of most-probable-number and restriction fragment length polymorphism analysis were used to analyze the abundance and diversity of ammonia-oxidizing bacteria in sediment of a Chinese shallow eutrophic urban lake (Lake Yuehu). Among the 5 sampling sites, ammonia concentration in interstitial water was positively proportional not only to the content of organic matter, but also to ammonia-oxidizing bacteria numbers (at a magnitude of 105 cells g-1 dry weight) in sediment significantly. Furthermore, the diversity of ammonia-oxidizing bacteria were determined by means of PCR primers targeting the amoA gene with five gene libraries created and restriction pattern analysis. The 13 restriction patterns were recorded with 4 ones being common among all sampling sites. The 8 restriction patterns including 4 unique ones were found at the site with the highest NH4+ concentrations in interstitial water, while, there were only common patterns without unique ones at the site with the lowest NH4+ concentrations in interstitial water. Phylogenetic analysis showed that the amoA fragments retrieved belong to Nitrosomonas oligotropha & ureae lineage, N. europaea lineage, N. communis lineage and Nitrosospira lineage, most of which were affiliated with the genus Nitrosomonas. The N. oligotropha & ureae-like bacteria were the dominant species. Thus, the abundance and diversity of sediment AOB is closely linked to ammonium status in eutrophic lakes. PMID:24031484

  10. Population diversity of ammonium oxidizers investigated by specific PCR amplification

    USGS Publications Warehouse

    Ward, B.B.; Voytek, M.A.; Witzel, K.-P.

    1997-01-01

    The species composition of ammonia-oxidizing bacteria in aquatic environments was investigated using PCR primers for 16S rRNA genes to amplify specific subsets of the total ammonia-oxidizer population. The specificity of the amplification reactions was determined using total genomic DNA from known nitrifying strains and non-nitrifying strains identified as having similar rDNA sequences. Specificity of amplification was determined both for direct amplification, using the nitrifier specific primers, and with nested amplification, in which the nitrifier primers were used to reamplify a fragment obtained from direct amplification with Eubacterial universal primers. The present level of specificity allows the distinction between Nitrosomonas europaea, Nitrosomonas sp. (marine) and the other known ammonia-oxidizers in the beta subclass of the Proteobacteria. Using total DNA extracted from natural samples, we used direct amplification to determine presence/absence of different species groups. Species composition was found to differ among depths in vertical profiles of lake samples and among samples and enrichments from various other aquatic environments. Nested PCR yielded several more positive reactions, which implies that nitrifier DNA was present in most samples, but often at very low levels.

  11. Final Report

    SciTech Connect

    R Paul Drake

    2004-01-12

    OAK-B135 This is the final report from the project Hydrodynamics by High-Energy-Density Plasma Flow and Hydrodynamics and Radiation Hydrodynamics with Astrophysical Applications. This project supported a group at the University of Michigan in the invention, design, performance, and analysis of experiments using high-energy-density research facilities. The experiments explored compressible nonlinear hydrodynamics, in particular at decelerating interfaces, and the radiation hydrodynamics of strong shock waves. It has application to supernovae, astrophysical jets, shock-cloud interactions, and radiative shock waves.

  12. Final Report

    SciTech Connect

    Segre, Carlo, Ph.D.

    2005-03-30

    In December of 2004, upon hearing of the DOE decision to terminate this grant, a no-cost extension was requested to allow us to expend residual funds from the 2004 calendar year. These funds have been used to support MR-CAT staff as we transition to other funding. As of this writing, the funds have been expended. Over the past four years of DOE operations funding, MR-CAT has become one of the most productive sectors at the Advanced Photon Source. This report will list the overall accomplishments of the collaboration during the time of DOE funding.

  13. Final Report,

    DTIC Science & Technology

    1980-12-01

    Academ for Interscience Methodology . Chapters 1, 2 and 3 of this report describe technical effort directed towards the development of methods to be used... methods for modifying the LINMIX soft target methodology and one method for the hard target methodology to make this improvement. It is assumed that the...AD-AI09 933 ACADEMY FOR INTERSCIENCE METHODOLOGY CHICAGO L F/G 15/3 DEC 80 M L KARDATZKE, S S ELLIS N0001-80-C-0070 UNCLASSIFIED AIM-8O-T-13 NL

  14. Final Report

    SciTech Connect

    Webb, Robert C.; Kamon, Teruki; Toback, David; Safonov, Alexei; Dutta, Bhaskar; Dimitri, Nanopoulos; Pope, Christopher; White, James

    2013-11-18

    Overview The High Energy Physics Group at Texas A&M University is submitting this final report for our grant number DE-FG02-95ER40917. This grant has supported our wide range of research activities for over a decade. The reports contained here summarize the latest work done by our research team. Task A (Collider Physics Program): CMS & CDF Profs. T. Kamon, A. Safonov, and D. Toback co-lead the Texas A&M (TAMU) collider program focusing on CDF and CMS experiments. Task D: Particle Physics Theory Our particle physics theory task is the combined effort of Profs. B. Dutta, D. Nanopoulos, and C. Pope. Task E (Underground Physics): LUX & NEXT Profs. R. Webb and J. White(deceased) lead the Xenon-based underground research program consisting of two main thrusts: the first, participation in the LUX two-phase xenon dark matter search experiment and the second, detector R&D primarily aimed at developing future detectors for underground physics (e.g. NEXT and LZ).

  15. Final Report

    SciTech Connect

    J. Toulouse

    2012-04-05

    The purpose of this project was to better understand the 'Multiscale Dynamics of Relaxor Ferroelectrics'. The output of the project is summarized in the narrative. The results of the work were presented at a number of different conferences and four papers were written, the references to which are also indicated in the report and which have also been uploaded on e-link. The multiscale dynamics of relaxors was clearly identified in the three characteristic temperatures that were identified. In particular, we were the first group to identify an intermediate temperature, T*, at which the correlations between off-center ions in relaxor cross-over from being dynamic to being static and giving rise to the characteristic relaxor behavior in the dielectric constant. Other groups have now confirmed the existence of such an intermediate temperature. We also made and reported two other observations: (1) a coherent interference phenomena (EIT-like effect) near the transition of several relaxors, which provides information on the nature and mechanism of the transition; and (2) in a similar way, inelastic neutron scattering results were interpreted as resonant scattering of acoustic phonons by localized modes in polar nanodomains. In parallel with the neutron scattering work, we also developed a theory of the scattering of phonons by the above localized modes. The theoretical development is very formal at this point and did not allow an easy comparison with the experimental results. This work is in progress.

  16. Final Report

    SciTech Connect

    Gurney, Kevin R.

    2015-01-12

    This document constitutes the final report under DOE grant DE-FG-08ER64649. The organization of this document is as follows: first, I will review the original scope of the proposed research. Second, I will present the current draft of a paper nearing submission to Nature Climate Change on the initial results of this funded effort. Finally, I will present the last phase of the research under this grant which has supported a Ph.D. student. To that end, I will present the graduate student’s proposed research, a portion of which is completed and reflected in the paper nearing submission. This final work phase will be completed in the next 12 months. This final workphase will likely result in 1-2 additional publications and we consider the results (as exemplified by the current paper) high quality. The continuing results will acknowledge the funding provided by DOE grant DE-FG-08ER64649.

  17. Test report :

    SciTech Connect

    Rose, David Martin; Schenkman, Benjamin L.; Borneo, Daniel R.

    2013-08-01

    The Department of Energy Office of Electricity (DOE/OE), Sandia National Laboratory (SNL) and the Base Camp Integration Lab (BCIL) partnered together to incorporate an energy storage system into a microgrid configured Forward Operating Base to reduce the fossil fuel consumption and to ultimately save lives. Energy storage vendors have supplied their systems to SNL Energy Storage Test Pad (ESTP) for functional testing and a subset of these systems were selected for performance evaluation at the BCIL. The technologies tested were electro-chemical energy storage systems comprised of lead acid, lithium-ion or zinc-bromide. MILSPRAY Military Technologies has developed an energy storage system that utilizes lead acid batteries to save fuel on a military microgrid. This report contains the testing results and some limited assessment of the Milspray Scorpion Energy Storage Device.

  18. Termination Report

    SciTech Connect

    Bruce McCarl; Dhazn Gillig

    2004-01-07

    OAK-B135 The results produced by this project include: (1) Development of econometrically estimated marginal abatement and associated production curves describing response of agricultural and forestry emissions/sink/offsets enhancements for use in integrated assessments. Curves were developed that reflected agricultural, and forestry production of traditional commodities, carbon and other greenhouse gas offsets and biofuels given signals of general commodity demand, and carbon and energy prices. This work was done jointly with Dr. Ronald Sands at PNNL. A paper from this is forthcoming as follows Gillig, D., B.A. McCarl, and R.D. Sands, ''Integrating Agricultural and Forestry GHG Mitigation Response into General Economy Frameworks: Developing a Family of Response Functions,'' Mitigation and Adaptation Strategies for Global Change, forthcoming, 2004. An additional effort was done involving dynamics and a second paper was prepared that is annex A to this report and is Gillig, D., and B.A. McCarl, ''Integrating Agricultural and Forestry Response to GHG Mitigation into General Economy Frameworks: Developing a Family of Response Functions using FASOM,'' 2004. (2) Integration of the non dynamic curves from (1) into in a version of the PNNL SGM integrated assessment model was done in cooperation with Dr. Ronald Sands at PNNL. The results were reported at the second DOE conference on sequestration in the paper listed just below and the abstract is in Annex B of this report. Sands, R.D., B.A. McCarl, and D. Gillig, ''Assessment of Terrestrial Carbon Sequestration Options within a United States Market for Greenhouse Gas Emissions Reductions,'' Presented at the Second Conference on Carbon Sequestration, Alexandria, VA, May 7, 2003. The results in their latest version show about half of the needed offsets by 2030 can be achieved through agriculture through a mix of sequestration and biofuel options. (3) Alternative agricultural sequestration estimates were developed in

  19. Test report :

    SciTech Connect

    Rose, David Martin; Schenkman, Benjamin L.; Borneo, Daniel R.

    2013-10-01

    The Department of Energy Office of Electricity (DOE/OE), Sandia National Laboratories (SNL) and the Base Camp Integration Lab (BCIL) partnered together to incorporate an energy storage system into a microgrid configured Forward Operating Base to reduce the fossil fuel consumption and to ultimately save lives. Energy storage vendors will be sending their systems to SNL Energy Storage Test Pad (ESTP) for functional testing and then to the BCIL for performance evaluation. The technologies that will be tested are electro-chemical energy storage systems comprising of lead acid, lithium-ion or zinc-bromide. Raytheon/KTech has developed an energy storage system that utilizes zinc-bromide flow batteries to save fuel on a military microgrid. This report contains the testing results and some limited analysis of performance of the Raytheon/KTech Zinc-Bromide Energy Storage System.

  20. Test Report :

    SciTech Connect

    Rose, David Martin; Schenkman, Benjamin L.; Borneo, Daniel R.

    2013-10-01

    The Department of Energy Office of Electricity (DOE/OE), Sandia National Laboratories (SNL) and the Base Camp Integration Lab (BCIL) partnered together to incorporate an energy storage system into a microgrid configured Forward Operating Base to reduce the fossil fuel consumption and to ultimately save lives. Energy storage vendors will be sending their systems to SNL Energy Storage Test Pad (ESTP) for functional testing and then to the BCIL for performance evaluation. The technologies that will be tested are electro-chemical energy storage systems comprising of lead acid, lithium-ion or zinc-bromide. GS Battery and EPC Power have developed an energy storage system that utilizes zinc-bromide flow batteries to save fuel on a military microgrid. This report contains the testing results and some limited analysis of performance of the GS Battery, EPC Power HES RESCU.

  1. Test report :

    SciTech Connect

    Rose, David Martin; Schenkman, Benjamin L.; Borneo, Daniel R.

    2013-08-01

    The Department of Energy Office of Electricity (DOE/OE), Sandia National Laboratory (SNL) and the Base Camp Integration Lab (BCIL) partnered together to incorporate an energy storage system into a microgrid configured Forward Operating Base to reduce the fossil fuel consumption and to ultimately save lives. Energy storage vendors will be sending their systems to SNL Energy Storage Test Pad (ESTP) for functional testing and then to the BCIL for performance evaluation. The technologies that will be tested are electro-chemical energy storage systems comprised of lead acid, lithium-ion or zinc-bromide. Princeton Power Systems has developed an energy storage system that utilizes lithium ion phosphate batteries to save fuel on a military microgrid. This report contains the testing results and some limited analysis of performance of the Princeton Power Systems Prototype Energy Storage System.

  2. Final Report

    SciTech Connect

    Yelton, John Martin; Mitselmakher, Guenakh; Korytov, Andrey; Avery, Paul; Furic, Ivan; Acosta, Darin; Konigsberg, Jacobo; Field, Richard; Matchev, Konstantin; Ramond, Pierre; Thorn, Richard; Sikivie, Pierre; Ray, Heather; Tanner, David

    2013-10-10

    We report on progress in a series of different directions within high energy physics research. 1. Neutrino research in hardware and software on the Minerva and MiniBooNE experiments 2. Experimental particle physics at the hadron colliders, with emphasis on research and development and data analysis on the CMS experiment operating at the CERN LHC. This includes research on the discovery and properties on the Higgs Boson. 3. Educational outreach through the Quarknet program, taking physics research into High School classrooms. 4. Theoretical and Phenomenological High Energy research, covering a broad range of activities ranging from fundamental theoretical issues to areas of immediate phenomenological importance. 5. Experiment searches for the Axion, as part of the ADMX experiment.

  3. Interim report

    SciTech Connect

    1985-06-01

    This Interim Report summarizes the research and development activities of the Superconducting Super Collider project carried out from the completion of the Reference Designs Study (May 1984) to June 1985. It was prepared by the SSC Central Design Group in draft form on the occasion of the DOE Annual Review, June 19--21, 1985. Now largely organized by CDG Divisions, the bulk of each chapter documents the progress and accomplishments to date, while the final section(s) describe plans for future work. Chapter 1, Introduction, provides a basic brief description of the SSC, its physics justification, its origins, and the R&D organization set up to carry out the work. Chapter 2 gives a summary of the main results of the R&D program, the tasks assigned to the four magnet R&D centers, and an overview of the future plans. The reader wishing a quick look at the SSC Phase I effort can skim Chapter 1 and read Chapter 2. Subsequent chapters discuss in more detail the activities on accelerator physics, accelerator systems, magnets and cryostats, injector, detector R&D, conventional facilities, and project planning and management. The magnet chapter (5) documents in text and photographs the impressive progress in successful construction of many model magnets, the development of cryostats with low heat leaks, and the improvement in current-carrying capacity of superconducting strand. Chapter 9 contains the budgets and schedules of the COG Divisions, the overall R&D program, including the laboratories, and also preliminary projections for construction. Appendices provide information on the various panels, task forces and workshops held by the CDG in FY 1985, a bibliography of COG and Laboratory reports on SSC and SSC-related work, and on private industrial involvement in the project.

  4. Complete genome sequence of Nitrosospira multiformis, an ammonia-oxidizing bacterium from the soil environment

    SciTech Connect

    Norton, Jeanette M.; Klotz, Martin G; Stein, Lisa Y; Arp, D J; Bottomley, Peter J; Chain, Patrick S. G.; Hauser, Loren John; Land, Miriam L; Larimer, Frank W; Shin, M; Starkenburg, Shawn R

    2008-01-01

    The complete genome of the ammonia-oxidizing bacterium, Nitrosospira multiformis (ATCC 25196T), consists of a circular chromosome and three small plasmids totaling 3,234,309 bp and encoding 2827 putative proteins. Of these, 2026 proteins have predicted functions and 801 are without conserved functional domains, yet 747 of these have similarity to other predicted proteins in databases. Gene homologs from Nitrosomonas europaea and N. eutropha were the best match for 42% of the predicted genes in N. multiformis. The genome contains three nearly identical copies of amo and hao gene clusters as large repeats. Distinguishing features compared to N. europaea include: the presence of gene clusters encoding urease and hydrogenase, a RuBisCO-encoding operon of distinctive structure and phylogeny, and a relatively small complement of genes related to Fe acquisition. Systems for synthesis of a pyoverdine-like siderophore and for acyl-homoserine lactone were unique to N. multiformis among the sequenced AOB genomes. Gene clusters encoding proteins associated with outer membrane and cell envelope functions including transporters, porins, exopolysaccharide synthesis, capsule formation and protein sorting/export were abundant. Numerous sensory transduction and response regulator gene systems directed towards sensing of the extracellular environment are described. Gene clusters for glycogen, polyphosphate and cyanophycin storage and utilization were identified providing mechanisms for meeting energy requirements under substrate-limited conditions. The genome of N. multiformis encodes the core pathways for chemolithoautotrophy along with adaptations for surface growth and survival in soil environments.

  5. Cycloheximide prevents the de novo polypeptide synthesis required to recover from acetylene inhibition in Nitrosopumilus maritimus.

    PubMed

    Vajrala, Neeraja; Bottomley, Peter J; Stahl, David A; Arp, Daniel J; Sayavedra-Soto, Luis A

    2014-06-01

    Developing methods to differentiate the relative contributions of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) to ammonia (NH3) oxidation has been challenging due to the lack of compounds that selectively inhibit AOA. In this study, we investigated the effects of specific bacteria- and eukaryote-selective protein synthesis inhibitors on the recovery of acetylene (C2H2)-inactivated NH3 oxidation in the marine AOA Nitrosopumilus maritimus and compared the results with recovery of the AOB Nitrosomonas europaea. C2 H2 irreversibly inhibited N. maritimus NH3 oxidation in a similar manner to what was observed previously with N. europaea. However, cycloheximide (CHX), a widely used eukaryotic protein synthesis inhibitor, but not bacteria-specific protein synthesis inhibitors (kanamycin and gentamycin), inhibited the recovery of NH3-oxidizing activity in N. maritimus. CHX prevented the incorporation of (14)CO2 -labeling into cellular proteins, providing further evidence that CHX acts as a protein synthesis inhibitor in N. maritimus. If the effect of CHX on protein synthesis can be confirmed among other isolates of AOA, the combination of C2H2 inactivation followed by recovery of NH3 oxidation either in the presence of bacteria-selective protein synthesis inhibitors or CHX might be used to estimate the relative contributions of AOB and AOA to NH3 oxidation in natural environments.

  6. Research Report

    NASA Astrophysics Data System (ADS)

    Dawes, Lyn

    2004-06-01

    This paper examines what is important about talk between learners during school science and, having identified this, suggests how we can ensure that what we consider important happens. By looking at the interaction between teachers and learners talking about science, it is possible to indicate ways in which learners can be helped to continue this learning conversation with one another when teacher support is withdrawn. Strategies for teaching and learning are examined. The paper reports on the findings of a research project designed to teach children how to negotiate their ideas about science concepts through rational dialogue. Children's development of scientific concepts in classrooms is undertaken through structured activity and mediated through oral language. Children must move forward simultaneously in their use of specialized vocabulary and in their understanding of current scientific explanations, models and ideas. New language and new ways of using language are learned by doing, which means for children, primarily speaking and listening. Children's understanding of science can benefit from teaching them to understand that spoken language is a powerful tool for thinking together.

  7. FINAL REPORT

    SciTech Connect

    Lettenmaier, Dennis

    2012-05-26

    We proposed to extend Maurer’s data sets through at least 2005 (to include extreme drought years in the Colorado basin). We updated and verified the forcings for tmin, tmax, and precipitation over the Colorado River basin at 1/8-deg spatial resolution through November 2008, with the potential to alter the resolution as needed (we subsequently extended the Maurer et al data set over the entire continental U.S. at 1/16 degree spatial resolution; see Livneh et al., 2013). We proposed to use either MODIS-based land cover data for recent years, or modification of the existing fixed seasonal cycle used in VIC (based on University of Maryland land cover data) to represent interannual variations in vegetation characteristics such as leaf area index (LAI) particularly in drought years. We assessed model performance with respect to evapotranspiration estimation through comparison of the model predictions with ground observations and in experiments that use time-varying and fixed seasonal LAI cycles (based on University of Maryland land cover data) in a test region of northwestern Mexico where the ground ET observations from eddy covariance tower sites are available for the period from 2001 to 2008 (Tang et al., 2011). We also proposed to implement statistical downscaling with an adjustment to constrain precipitation changes at the GCM level. These simulations were performed, using 20 IPCC AR4 GCMs over the Colorado River basin with two global emissions scenarios, and are reported in Vano et al., 2014. Task 2: Coupled model implementation We proposed to implement the “standard” climate version of WRF, as used by collaborator Ruby Leung in NARCCAP simulations (see Section 5.4), and perform tests to assure that model output for runs equivalent to NARCCAP Phase 1 (reanalysis boundary conditions) are consistent. We proposed do test sensitivity to higher spatial resolution. We made a run of 11 years’ length with the “standard” version of WRF, forced by NCEP/DOE with

  8. Main Report

    PubMed Central

    2006-01-01

    Background: States vary widely in their use of newborn screening tests, with some mandating screening for as few as three conditions and others mandating as many as 43 conditions, including varying numbers of the 40+ conditions that can be detected by tandem mass spectrometry (MS/MS). There has been no national guidance on the best candidate conditions for newborn screening since the National Academy of Sciences report of 19751 and the United States Congress Office of Technology Assessment report of 1988,2 despite rapid developments since then in genetics, in screening technologies, and in some treatments. Objectives: In 2002, the Maternal and Child Health Bureau (MCHB) of the Health Resources and Services Administration (HRSA) of the United States Department of Health and Human Services (DHHS) commissioned the American College of Medical Genetics (ACMG) to: Conduct an analysis of the scientific literature on the effectiveness of newborn screening.Gather expert opinion to delineate the best evidence for screening for specified conditions and develop recommendations focused on newborn screening, including but not limited to the development of a uniform condition panel.Consider other components of the newborn screening system that are critical to achieving the expected outcomes in those screened. Methods: A group of experts in various areas of subspecialty medicine and primary care, health policy, law, public health, and consumers worked with a steering committee and several expert work groups, using a two-tiered approach to assess and rank conditions. A first step was developing a set of principles to guide the analysis. This was followed by developing criteria by which conditions could be evaluated, and then identifying the conditions to be evaluated. A large and broadly representative group of experts was asked to provide their opinions on the extent to which particular conditions met the selected criteria, relying on supporting evidence and references from the

  9. Chemical Data Reporting

    EPA Pesticide Factsheets

    The Chemical Data Reporting (CDR) site provides information on reporting requirements under TSCA's Chemical Data Reporting Rule. The site provides instruction to data submitters on how to report and enable users to download the reported information.

  10. Final report

    SciTech Connect

    Dobbs, Fred C.

    2003-01-15

    species of flagellates, Spumella sp. and Bodo sp. (identifications are tentative) were isolated from South Oyster sediments by repetitive serial dilution/extinction method. Protistan cells were cultured with Cereal leaf Prescott medium and pelleted by centrifugation. Protistan DNAs were extracted with a DNA extraction kit (Sigma Co.) and the sequencing of their SSrDNA is underway. Finally, to follow up on our collaboration of Dr. Bill Johnson (Univ. of Utah), one of the co-PIs under the same NABIR umbrella, we are pleased to report we have successfully tested antibody-ferrographic capture of protists (See previous year's report for more background). Polyclonal FITC-conjugated antibody specific for a flagellate, Spumella sp., was produced by Rockland Inc., and we now are able to enumerate that species using ferrographic capture. There are, however, some issues of non-specific staining that remain to be resolved.

  11. Final report

    SciTech Connect

    Joseph H. Simmons; Tracie J. Bukowski

    2002-08-07

    determine if photocarriers could be collected. Thus, we tested a variety of semiconductor-glass nano-composite structures for photoconductivity. Tests were conducted in collaboration with the Laser Physics Division at Sandia National Laboratories. Nano-composite samples were formed consisting of Ge nanocrystals embedded in an indium-tin-oxide matrix. Photoconductivity measurements were conducted with exposure of the films to sub-bandgap and super-bandgap light. The results showed a clear photoconductivity effect arising from exposure to super-bandgap light only. These results suggest that the high-efficiency photovoltaic cell structure proposed in DOE sponsored U.S. Patent 5,720,827 is viable. The results of fabrication studies, structural characterization studies and photovoltaic measurements are presented in the report. This report is taken from a PhD dissertation of Tracie J. Bukowski submitted to the University of Florida in May 2002. ''The optical and photoconductive response in germanium quantum dots and indium tin oxide composite thin film structures,'' Dr. Bukowski conducted her PhD study under this grant at the University of Arizona and under Grant No DE-FG05-91ER45462 at the University of Florida, as well as during a two-year fellowship at Sandia National Laboratories.

  12. Planktonic and biofilm-grown nitrogen-cycling bacteria exhibit different susceptibilities to copper nanoparticles.

    PubMed

    Reyes, Vincent C; Opot, Stephen O; Mahendra, Shaily

    2015-04-01

    Proper characterization of nanoparticle (NP) interactions with environmentally relevant bacteria under representative conditions is necessary to enable their sustainable manufacture, use, and disposal. Previous nanotoxicology research based on planktonic growth has not adequately explored biofilms, which serve as the predominant mode of bacterial growth in natural and engineered environments. Copper nanoparticle (Cu-NP) impacts on biofilms were compared with respective planktonic cultures of the ammonium-oxidizing Nitrosomonas europaea, nitrogen-fixing Azotobacter vinelandii, and denitrifying Paracoccus denitrificans using a suite of independent toxicity diagnostics. Median inhibitory concentration (IC50) values derived from adenosine triphosphate (ATP) for Cu-NPs were lower in N. europaea biofilms (19.6 ± 15.3 mg/L) than in planktonic cells (49.0 ± 8.0 mg/L). However, in absorbance-based growth assays, compared with unexposed controls, N. europaea growth rates in biofilms were twice as resilient to inhibition than those in planktonic cultures. Similarly, relative to unexposed controls, growth rates and yields of P. denitrificans in biofilms exposed to Cu-NPs were 40-fold to 50-fold less inhibited than those in planktonic cells. Physiological evaluation of ammonium oxidation and nitrate reduction suggested that biofilms were also less inhibited by Cu-NPs than planktonic cells. Furthermore, functional gene expression for ammonium oxidation (amoA) and nitrite reduction (nirK) showed lower inhibition by NPs in biofilms relative to planktonic-grown cells. These results suggest that biofilms mitigate NP impacts, and that nitrogen-cycling bacteria in wastewater, wetlands, and soils might be more resilient to NPs than planktonic-based assessments suggest.

  13. Phylogeny and functional expression of ribulose 1,5-bisphosphate carboxylase/oxygenase from the autotrophic ammonia-oxidizing bacterium Nitrosospira sp. isolate 40KI.

    PubMed

    Utåker, Janne B; Andersen, Kjell; Aakra, Agot; Moen, Birgitte; Nes, Ingolf F

    2002-01-01

    The autotrophic ammonia-oxidizing bacteria (AOB), which play an important role in the global nitrogen cycle, assimilate CO(2) by using ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO). Here we describe the first detailed study of RubisCO (cbb) genes and proteins from the AOB. The cbbLS genes from Nitrosospira sp. isolate 40KI were cloned and sequenced. Partial sequences of the RubisCO large subunit (CbbL) from 13 other AOB belonging to the beta and gamma subgroups of the class Proteobacteria are also presented. All except one of the beta-subgroup AOB possessed a red-like type I RubisCO with high sequence similarity to the Ralstonia eutropha enzyme. All of these new red-like RubisCOs had a unique six-amino-acid insert in CbbL. Two of the AOB, Nitrosococcus halophilus Nc4 and Nitrosomonas europaea Nm50, had a green-like RubisCO. With one exception, the phylogeny of the AOB CbbL was very similar to that of the 16S rRNA gene. The presence of a green-like RubisCO in N. europaea was surprising, as all of the other beta-subgroup AOB had red-like RubisCOs. The green-like enzyme of N. europaea Nm50 was probably acquired by horizontal gene transfer. Functional expression of Nitrosospira sp. isolate 40KI RubisCO in the chemoautotrophic host R. eutropha was demonstrated. Use of an expression vector harboring the R. eutropha cbb control region allowed regulated expression of Nitrosospira sp. isolate 40KI RubisCO in an R. eutropha cbb deletion strain. The Nitrosospira RubisCO supported autotrophic growth of R. eutropha with a doubling time of 4.6 h. This expression system may allow further functional analysis of AOB cbb genes.

  14. Phylogeny and Functional Expression of Ribulose 1,5-Bisphosphate Carboxylase/Oxygenase from the Autotrophic Ammonia-Oxidizing Bacterium Nitrosospira sp.Isolate 40KI

    PubMed Central

    Utåker, Janne B.; Andersen, Kjell; Aakra, Ågot; Moen, Birgitte; Nes, Ingolf F.

    2002-01-01

    The autotrophic ammonia-oxidizing bacteria (AOB), which play an important role in the global nitrogen cycle, assimilate CO2 by using ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO). Here we describe the first detailed study of RubisCO (cbb) genes and proteins from the AOB. The cbbLS genes from Nitrosospira sp. isolate 40KI were cloned and sequenced. Partial sequences of the RubisCO large subunit (CbbL) from 13 other AOB belonging to the β and γ subgroups of the class Proteobacteria are also presented. All except one of the β-subgroup AOB possessed a red-like type I RubisCO with high sequence similarity to the Ralstonia eutropha enzyme. All of these new red-like RubisCOs had a unique six-amino-acid insert in CbbL. Two of the AOB, Nitrosococcus halophilus Nc4 and Nitrosomonas europaea Nm50, had a green-like RubisCO. With one exception, the phylogeny of the AOB CbbL was very similar to that of the 16S rRNA gene. The presence of a green-like RubisCO in N. europaea was surprising, as all of the other β-subgroup AOB had red-like RubisCOs. The green-like enzyme of N. europaea Nm50 was probably acquired by horizontal gene transfer. Functional expression of Nitrosospira sp. isolate 40KI RubisCO in the chemoautotrophic host R. eutropha was demonstrated. Use of an expression vector harboring the R. eutropha cbb control region allowed regulated expression of Nitrosospira sp. isolate 40KI RubisCO in an R. eutropha cbb deletion strain. The Nitrosospira RubisCO supported autotrophic growth of R. eutropha with a doubling time of 4.6 h. This expression system may allow further functional analysis of AOB cbb genes. PMID:11751824

  15. Final Report

    SciTech Connect

    Hameed A. Naseem, Husam H. Abu-Safe

    2007-02-09

    was demonstrated to be at least two orders of magnitude lower that that reported in the literature before. Polysilicon was successfully achieved on polyimide (Kapton©) films. Thin film Si solar cells on lightweight stoable polymer offer great advantage for terrestrial and space power applications. In summary we have demonstrated through this research the viability of producing low cost nano-, poly-, and epitaxial Si material on substrates of choice for applications in economically viable environmentally friendly sustainable solar power systems. This truly enabling technology has widespread applications in multibillion dollar electronic industry and consumer products.

  16. Final Report

    SciTech Connect

    Michael C. Weinberg; Lori L. Burgner; Joseph H. Simmons

    2003-05-23

    OAK B135 The formation of metastable crystalline phases in lithium disilicate glass has been a subject of controversy for decades. Here, one aspect of this problem relating to the stability of these non-equilibrium phases when glasses are heated for extended time periods in the nucleation regime is addressed. The results of a systematic experimental investigation on the persistence of metastable phases and the factors that may influence the appearance of such phases, e.g., water content, impurities, glass composition, and glass preparation procedure are presented. Growth rates of lithium disilicate crystals in lithium disilicate glass are measured as a function water concentration in the glass and of temperature in the deeply undercooled regime. The growth rate data obtained in this work are combined with data reported in the literature and used to assess the applicability of standard models of crystal growth for the description of experimental results over a very broad temperature range. The reduced growth rate versus undercooling graph is found to consist of three regimes. For undercoolings less than 140°C, the reduced growth rate curve is suggestive of either 2-D surface nucleation or screw dislocation growth. For undercoolings greater than 400°C, the reduced growth rate plot suggests the operative crystal growth mechanism is 2-D surface nucleation, but detailed calculations cast doubt upon this conclusion. In the intermediate undercooling range, there appears to be some sort of transitional behavior for which none of the standard models appear to be applicable. Further, it is observed that small differences in the viscosity data employed can produce enormous differences in the predicted growth rates at larger undercoolings. Results of the kinetic analyses conducted herein seem to indicate that the nature of the kinetic rate coefficient used in the standard growth models may be incorrect. Nucleation rates of sodium metasilicate crystals in a sodium silicate

  17. Final Report

    SciTech Connect

    Robert D. Cess

    2008-12-05

    Paper number 1 addresses the fact that the procedure used in the Earth Radiation Budget Experiment for identifying the presence of clouds over snow/ice surfaces is known to have shortcomings, and this is corroborated through use of surface insolation measurements at the South Pole as an independent means of identifying clouds. These surface insolation measurements are then used to validate the more detailed cloud identification scheme used in the follow-up Clouds and the Earth's Radiant Energy System (CERES), and this validation is extended to the polar night through use of CERES measurements of the outgoing longwave radiation. General circulation models (GCMs) are highly sophisticated computer tools for modeling climate change, and they incorporate a large number of physical processes and variables. One of the most important challenges is to properly account for water vapor (clouds and humidity) in climate warming. In this Perspective, Cess discusses results reported in the same issue by Soden et al. in which water vapor feedback effects are tested by studying moistening trends in the upper troposphere. Satellite observations of atmospheric water vapor are found to agree well with moisture predictions generated by one of the key GCMs, showing that these feedback effects are being properly handled in the model, which eliminates a major potential source of uncertainty. Zhou and Cess [2001] developed an algorithm for retrieving surface downwelling longwave radiation (SDLW) based upon detailed studies using radiative transfer model calculations and surface radiometric measurements. Their algorithm linked clear sky SDLW with surface upwelling longwave flux and column precipitable water vapor. For cloudy sky cases, they used cloud liquid water path as an additional parameter to account for the effects of clouds. Despite the simplicity of their algorithm, it performed very well for most geographical regions except for those regions where the atmospheric conditions near

  18. Nitrification and Nitrifying Bacteria in the Lower Seine River and Estuary (France)

    PubMed Central

    Cébron, Aurélie; Berthe, Thierry; Garnier, Josette

    2003-01-01

    The Achères wastewater treatment plant, located just downstream of Paris, discharges its effluents into the lower Seine River. The effluents contain large numbers of heterotrophic bacteria, organic matter, and ammonium and are a source of nitrifying bacteria. As a result, degradation of organic matter by heterotrophic bacteria and subsequent oxygen depletion occur immediately downstream of the effluent outlet, whereas nitrifying bacteria apparently need to build up a significant biomass before ammonium oxidation significantly depletes the oxygen. We quantified the potential total nitrifying activity and the potential activities of the ammonia- and nitrite-oxidizing communities along the Seine River. In the summer, the maximum nitrifying activity occurs in the upper freshwater estuary, ∼200 km downstream of Achères. The quantities of nitrifying bacteria, based on amoA gene copy numbers, and of Nitrobacter organisms, based on 16S rRNA gene copy numbers, were correlated with the potential nitrifying activities. The species composition of ammonia-oxidizing bacteria was investigated at two sites: the Triel station just downstream from Achères (km 84) and the Seine freshwater estuary at the Duclair station (km 278). By means of PCR primers targeting the amoA gene, a gene library was created. Phylogenetic analysis revealed that the majority of the analyzed clones at both sites were affiliated with the genus Nitrosomonas. The Nitrosomonas oligotropha- and Nitrosomonas urea-related clones represented nearly 81% of the community of ammonia-oxidizing bacteria at Triel and 60% at Duclair. Two other ammonia-oxidizing clusters of the β subclass of the Proteobacteria, i.e., Nitrosomonas europaea- and Nitrosospira-like bacteria, were found in smaller numbers. The major change in the ammonia-oxidizing community between the two stations along the Seine River-upper estuary continuum was the replacement of the N. oligotropha- and N. urea-related bacteria by the Nitrosospira

  19. Can nitrification bring us to Mars? The role of microbial interactions on nitrogen recovery in life support systems

    NASA Astrophysics Data System (ADS)

    Christiaens, Marlies E. R.; Lasseur, Christophe; Clauwaert, Peter; Boon, Nico; Ilgrande, Chiara; Vlaeminck, Siegfried

    2016-07-01

    Human habitation in space requires artificial environment recirculating fundamental elements to enable the highest degree of autonomy . The European Space Agency, supported by a large consortoium of European organisationsdevelop the Micro-Ecological Life Support System (MELiSSA) to transform the mission wastes waste (a.o. organic fibers, CO2, and urine) into water, oxygen, and food (Lasseur et al., 2010). Among these wastes, astronauts' urine has a high potential to provide nitrogen as a fertilizer for food production. As higher plant growth in space is typically proposed to be performed in hydroponics, liquid fertilizer containing nitrates is preferred. An Additional Unit for Water Treatment is developed for urine nitrification by means of a synthetic microbial community. The key players in this consortium are ureolytic bacteria to hydrolyse the main nitrogen source in urine, urea, to ammonium and carbon dioxide as well as oxidation of organic compounds present in urine, ammonium oxidizing bacteria (AOB) to convert ammonium to nitrite (nitritation), and the nitrate oxidizing bacteria (NOB) to produce nitrate (nitratation). Pure AOB strains Nitrosomonas ureae Nm10 and Nitrosomonas europaea ATCC 19718, pure NOB strains Nitrobacter winogradskyi Nb-255 and Nitrobacter vulgaris Z, and interactions within synthetic consortia of one AOB and one NOB or all together were tested. As the initial salinity of fresh urine can be as high as 30 mS/cm, the functionality of selected pure strains and synthetic consortia was evaluated by means of the nitritation and nitratation activity at varying NaCl salinities (5, 10, and 30 mS/cm). The nitritation activity of pure AOB strains was compared with the synthetic consortia. Both N. ureae and Ns. europaea benefit from the presence of Nb. winogradskyi as the ammonium oxidation rates of 1.7 ± 0.7 and 6.4 ± 0.6 mg N/L.d at 5 mS/cm, respectively, doubled. These results are in line with the findings of Perez et al (2015) observing a lower

  20. Technical report, Onondaga Lake, New York. Main report. Final report

    SciTech Connect

    Not Available

    1992-01-01

    This technical report on Onondaga Lake, New York has compiled existing data to determine which water quality and environmental enhancements are advisable. The report identifies sediment and water quality problems and needs, potential clean-up methodologies, fisheries and fish habitat improvements, and water quality improvements.

  1. Breastfeeding Report Card 2014

    MedlinePlus

    ... Weight Breastfeeding Micronutrient Malnutrition State and Local Programs Breastfeeding Report Cards Recommend on Facebook Tweet Share Compartir ... National Immunization Survey data from 2014 and 2015. Breastfeeding Report Card, 2016 Download report [PDF-2.72MB] ...

  2. Report Bee Kills

    EPA Pesticide Factsheets

    EPA uses incident report data to help inform our pesticide regulatory decisions. Information from these reports helps us identify patterns of bee kills associated with the use of specific pesticides or active ingredients. Here's how to report incidents.

  3. ISLAY containment data report

    SciTech Connect

    Stubbs, T.; Heinle, R.

    1997-06-01

    This containment data report for the ISLAY event provides a description of the event, including the site, emplacement, and instrumentation. Stemming performance is reported, including radiation pressure and motion. Collapse phenomena are reported, including motion and radiation pressure. Measurements on the emplacement pipe are reported, including motion, pressure, temperature, and radiation.

  4. Lab Report Blues

    ERIC Educational Resources Information Center

    Diaz, Andrew

    2004-01-01

    For middle school students, writing a formal lab report can be challenging. For middle level teachers, reading students lab reports can be overwhelming. After grading report after report with incomplete procedures, incorrect graphs, and missing conclusions, the author's frustration level was at an all-time high. Ready to try anything, he thought,…

  5. Technical Report Bibliography.

    ERIC Educational Resources Information Center

    Hoffnagle, Gale F.

    A Bibliography of all unclassified technical reports prepared by USAF Environmental Health Laboratory, McClellan is presented. It contains a listing by subject matter and a listing of all reports by year with report number and abstract. The reports cover most areas of environmental topics such as air, water, noise, and radiation pollution. (NTIS)

  6. Using Polls in Education Reporting: Reporter Guide

    ERIC Educational Resources Information Center

    Wieder, Ben

    2014-01-01

    Every four years, public opinion polls become a national obsession in the months leading up to the presidential election, with new results breathlessly reported nearly every day. But polling is not exclusively the province of political reporters. A handful of national surveys released each year focus on education, including the Phi Delta…

  7. Production of NO and N(inf2)O by Pure Cultures of Nitrifying and Denitrifying Bacteria during Changes in Aeration

    PubMed Central

    Kester, R. A.; De Boer, W.; Laanbroek, H. J.

    1997-01-01

    Peak emissions of NO and N(inf2)O are often observed after wetting of soil. The reactions to sudden changes in the aeration of cultures of nitrifying and denitrifying bacteria with respect to NO and N(inf2)O emissions were compared to obtain more information about the microbiological aspects of peak emissions. In continuous culture, the nitrifier Nitrosomonas europaea and the denitrifiers Alcaligenes eutrophus and Pseudomonas stutzeri were cultured at different levels of aeration (80 to 0% air saturation) and subjected to changes in aeration. The relative production of NO and N(inf2)O by N. europaea, as a percentage of the ammonium conversion, increased from 0.87 and 0.17%, respectively, at 80% air saturation to 2.32 and 0.78%, respectively, at 1% air saturation. At 0% air saturation, ammonium oxidation and N(inf2)O production ceased but NO production was enhanced. Coculturing of N. europaea with the nitrite oxidizer Nitrobacter winogradskyi strongly reduced the relative levels of NO and N(inf2)O production, probably as an effect of the lowered nitrite concentration. After lowering the aeration, N. europaea produced large short-lasting peaks of NO and N(inf2)O emissions in the presence but not in the absence of nitrite. A. eutrophus and P. stutzeri began to denitrify below 1% air saturation, with the former accumulating nitrite and N(inf2)O and the latter reducing nitrate almost completely to N(inf2). Transition of A. eutrophus and P. stutzeri from 80 to 0% air saturation resulted in transient maxima of denitrification intermediates. Such transient maxima were not observed after transition from 1 to 0%. Reduction of nitrate by A. eutrophus continued 48 h after the onset of the aeration, whereas N(inf2)O emission by P. stutzeri increased for only a short period. It was concluded that only in the presence of nitrite are nitrifiers able to dominate the NO and N(inf2)O emissions of soils shortly after a rainfall event. PMID:16535707

  8. Reconnaissance Reports Guide

    DTIC Science & Technology

    2014-01-23

    SALUTE ) re- port should normally be provided in addition to this report to amplify these enemy sightings and further clar- ify the enemy situation...yes) and submit a SPOTREP/ SALUTE report separately. If no enemy has been observed, report NIL in this line of the report. LIMA Remarks. Any other...Weapons, especially any weapons or weapons systems that could jeopardize the accomplishment of the amphibious operation. Note: A SPOTREP/ SALUTE report

  9. Data Network Weather Service Reporting - Final Report

    SciTech Connect

    Michael Frey

    2012-08-30

    A final report is made of a three-year effort to develop a new forecasting paradigm for computer network performance. This effort was made in co-ordination with Fermi Lab's construction of e-Weather Center.

  10. Custom Report | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  11. About the Report | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  12. Report Highlights | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  13. 1995 PVUSA progress report. Final report

    SciTech Connect

    1996-03-01

    Photovoltaics for Utility Scale Applications (PVUSA) is a national public-private partnership that is assessing and demonstrating the viability of utility-scale (US) photovoltaic (PV) electric generation systems and recent developments in PV module technology. This report updates the project`s progress, reviews the status and performance of the various PV installations during 1995, summarizes key accomplishments and conclusions, and serves as the final report under Pacific Gas and Electric Company`s project management.

  14. Reporting the Scores.

    ERIC Educational Resources Information Center

    Hendrickson, Peter

    2002-01-01

    Describes how to report test data to parents and the news media. Provides examples from the Evergreen School District in Vancouver, Washington. Includes specific suggestions on how to work with reports. (PKP)

  15. Research Reports: Marijuana

    MedlinePlus

    ... Publications » Research Reports » Marijuana » Letter From the Director Marijuana Email Facebook Twitter Letter From the Director Photo ... research-reports/marijuana press ctrl+c to copy Marijuana and Cannabinoids: A Neuroscience Research Summit March 22- ...

  16. RY 2004 Reporting Forms

    EPA Pesticide Factsheets

    The TRI reporting forms on this page are for reference only. Do not submit these forms to EPA. All facilities are required to submit their TRI data electronically using the TRI-MEweb application, per the TRI Electronic Reporting Rule.

  17. RY 2009 Reporting Forms

    EPA Pesticide Factsheets

    The TRI reporting forms on this page are for reference only. Do not submit these forms to EPA. All facilities are required to submit their TRI data electronically using the TRI-MEweb application, per the TRI Electronic Reporting Rule.

  18. RY 2003 Reporting Forms

    EPA Pesticide Factsheets

    The TRI reporting forms on this page are for reference only. Do not submit these forms to EPA. All facilities are required to submit their TRI data electronically using the TRI-MEweb application, per the TRI Electronic Reporting Rule.

  19. Technical report writing

    NASA Technical Reports Server (NTRS)

    Vidoli, Carol A.

    1992-01-01

    This manual covers the fundamentals of organizing, writing, and reviewing NASA technical reports. It was written to improve the writing skills of LeRC technical authors and the overall quality of their reports.

  20. USSR Report Agriculture.

    DTIC Science & Technology

    2007-11-02

    This is USSR Report for Agriculture. It contains the issues with different topics on Major Crop Progress and Weather Reporting, Livestock, Regional Development , Agro-Economics and Organization, Tilling and Cropping Technology.

  1. Oil Discharge Reporting Requirements

    EPA Pesticide Factsheets

    If a facility or vessel discharges oil to navigable waters or adjoining shorelines, the owner/operator is required to follow certain federal reporting requirements. This fact sheet outlines those reporting requirements.

  2. NPDES Permit Status Reports

    EPA Pesticide Factsheets

    These reports show the backlog status nationwide, based on EPA databases and input from EPA regions and states. The reports show a snapshot in time, keep in mind that the status of facilities and the universe of permits change.

  3. Evaluating quantitative research reports.

    PubMed

    Russell, Cynthia L

    2005-01-01

    As a novice reviewer, it is often difficult to trust your evaluation of a research report. You may feel uncertain in your interpretations. These are common concerns and can be remedied by reading and discussing research reports on research listservs, through journal clubs, or with other nephrology nurses. Practice using the criteria for research report evaluation and you too can perfect critiquing a research report!

  4. USSR Report, Agriculture.

    DTIC Science & Technology

    2007-11-02

    obtained from copyright owner, JPRS-UAG-84-021 12 June 1984 USSR REPORT AGRICULTURE CONTENTS MAJOR CROP PROGRESS AND WEATHER REPORTING Details...KHOZYAYSTVA, No 3, Mar 84) - b - MAJOR CROP PROGRESS AND WEATHER REPORTING DETAILS OF SOWING PROGRESS IN ROSTOVSKAYA OBLAST Moscow SEL’SKAYA ZHIZN1...MAJOR CROP PROGRESS AND WEATHER REPORTING SPRING SOWING OPERATIONS IN BELORUSSIAN SSR REVIEWED Minsk SEL’SKAYA GAZETA in Russian 20 Apr 84 p 1

  5. Final Technical Report

    SciTech Connect

    Schuur, Edward; Luo, Yiqi

    2016-12-01

    This final grant report is a continuation of the final grant report submitted for DE-SC0006982 as the Principle Investigator (Schuur) relocated from the University of Florida to Northern Arizona University. This report summarizes the original project goals, as well as includes new project activities that were completed in the final period of the project.

  6. Healthcare. State Report

    ERIC Educational Resources Information Center

    Carnevale, Anthony P.; Smith, Nicole; Gulish, Artem; Beach, Bennett H.

    2012-01-01

    This report projects education requirements linked to forecasted job growth in healthcare by state and the District of Columbia from 2010 through 2020. It complements a larger national report which projects educational demand for healthcare for the same time period. The national report shows that with or without Obamacare, the United States will…

  7. Teaching Technical Report Writing

    ERIC Educational Resources Information Center

    De Pasquale, Joseph A.

    1977-01-01

    A high school electronics teacher describes the integration of technical report writing in the electronics program for trade and industrial students. He notes that the report writing rather than just recording data seemed to improve student laboratory experience but further improvements in the program are needed. A sample lab report is included.…

  8. Toward a Social Report.

    ERIC Educational Resources Information Center

    Department of Health, Education, and Welfare, Washington, DC.

    This report, prepared at the request of President Johnson, represents an attempt by social scientists to look at several important aspects of the quality of American Life, and digest what is known about progress toward generally accepted social goals. It is not in itself a social report, but a step toward the development of a social report and a…

  9. BC Jurisdictional Report

    ERIC Educational Resources Information Center

    British Columbia Council on Admissions and Transfer, 2010

    2010-01-01

    This report was submitted by the BC Council on Admissions (BCCAT) to the Council of Ministers of Education, Canada (CMEC). This report is a summary of projects and activities completed by BCCAT during the period from April 1, 2009, to March 31, 2010. The purpose of this report is to inform the Council of Ministers of Education, Canada (CMEC) of…

  10. CEDEFOP Annual Report, 2001.

    ERIC Educational Resources Information Center

    European Centre for the Development of Vocational Training, Thessaloniki (Greece).

    This is a report of major achievements and activities undertaken by Cedefop during 2001, and it describes efforts to achieve the aims laid down in the work program. Chapters 1-11 each focus on specified Proposed Outcomes 2001 and report results reached in these areas: reporting system on lifelong learning; promoting competencies for the knowledge…

  11. Organic solvent topical report

    SciTech Connect

    Cowley, W.L.

    1998-04-30

    This report is the technical basis for the accident and consequence analyses used in the Hanford Tank Farms Basis for Interim Operation. The report also contains the scientific and engineering information and reference material needed to understand the organic solvent safety issue. This report includes comments received from the Chemical Reactions Subcommittee of the Tank Advisory Panel.

  12. 2014 Site Environmental Report

    SciTech Connect

    Paquette, Douglas; Remien, Jason; Foley, Brian; Burke, John; Dorsch, William; Ratel, Karen; Howe, Robert; Welty, Tim; Williams, Jeffrey; Pohlpt, Peter; Lagattolla, Richard; Metz, Robert; Milligan, James; Lettieri, Lawrence

    2015-10-01

    BNL prepares an annual Site Environmental Report (SER) in accordance with DOE Order 231.1B, Environment, Safety and Health Reporting. The report is written to inform the public, regulators, employees, and other stakeholders of the Laboratory’s environmental performance during the calendar year in review.

  13. Pesticide reregistration progress report

    SciTech Connect

    Not Available

    1993-01-01

    The report is produced by the Special Review and Reregistration Division (SRRD), Office of Pesticide Programs, U.S. Environmental Protection Agency (EPA), on progress towards pesticide reregistration as mandated under 1988 amendments to the Federal Insecticide, Fungicide, and Rodenticide Act. The report shows the status of reregistration through the first quarter of the 1993 fiscal year. SRRD is in the process of re-evaluating the format and information in the Progress Report, as a result of the October 1992 Customer Survey sent to the recipients of the report. Results of the survey will be incorporated in the April 1993 issue of the report.

  14. Spencermartinsiella europaea gen. nov., sp. nov., a new member of the family Trichomonascaceae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ten strains of a novel heterothallic yeast species were isolated from rotten wood collected at different locations in Hungary. Analysis of gene sequences for the D1/D2 domain of the large subunit ribosomal RNA, as well as analysis of concatenated gene sequences for the nearly complete nuclear large...

  15. SNP-based markers for discriminating olive (Olea europaea L.) cultivars.

    PubMed

    Reale, S; Doveri, S; Díaz, A; Angiolillo, A; Lucentini, L; Pilla, F; Martín, A; Donini, P; Lee, D

    2006-09-01

    A set of 11 polymorphic markers (1 cleaved amplified polymorphic sequence (CAPS), 2 sequence-characterized amplified regions (SCARs), and 8 single-nucleotide polymorphism (SNP)-derived markers) was obtained for olive cultivar identification by comparing DNA sequences from different accessions. Marker development was more efficient, using sequences from the database rather than cloning arbitrary DNA fragments. Analyses of the sequences of 3 genes from 11 diverse cultivars revealed an SNP frequency of 1 per 190 base pairs in exons and 1 per 149 base pairs in introns. Most mutations were silent or had little perceptible effect on the polypeptide encoded. The higher incidence of transversions (55%) suggests that methylation is not the major driving force for DNA base changes. Evidence of linkage disequilibrium in 2 pairs of markers has been detected. The set of predominantly SNP-based markers was used to genotype 65 olive samples obtained from Europe and Australia, and was able clearly to discriminate 77% of the cultivars. Samples, putatively of the same cultivar but derived from different sources, were revealed as identical, demonstrating the utility of these markers as tools for resolving nomenclature issues. Genotyping data were used for constructing a dendrogram by UPGMA cluster analysis using the simple matching similarity coefficient. Relationships between cultivars are discussed in relation to the route of olive's spread.

  16. Behavior of storage lipids during development and germination of olive ( Olea europaea L.) pollen.

    PubMed

    Rodríguez-García, M I; M'rani-Alaoui, M; Fernández, M C

    2003-06-01

    The presence of abundant oil bodies in the mature olive pollen grain has led us to focus on the behavior of these lipid bodies during pollen development and in vitro pollen germination. The appearance, increase, and accumulation of lipid bodies have been determined by following the sequential development of the pollen grain. Semithin slices of anthers and pollen grains were stained with Sudan Black B in order to identify neutral lipids. Ultrastructural studies were also carried out. Our results show a notable increase in lipid bodies between the young-pollen-grain stage and the mature-pollen-grain stage. Substantial polarization of lipid bodies was observed after 1 or 2 h of pollen incubation in germination medium. During pollen tube growth, the lipid bodies are located near the germinative aperture after 3 h of incubation, as well as inside the pollen tube, thus suggesting that the lipid bodies move from the pollen grain to the pollen tube. After 7 h of germination the presence of lipid bodies inside the pollen tube is no longer substantial. Our results support the idea that lipid bodies are involved in pollen germination, stigma penetration, and pollen tube growth. These results are discussed in connection with their implications for the pollen germination process.

  17. Olive (Olea europaea L.) tree nitrogen status is a key factor for olive oil quality.

    PubMed

    Erel, Ran; Kerem, Zohar; Ben-Gal, Alon; Dag, Arnon; Schwartz, Amnon; Zipori, Isaac; Basheer, Loai; Yermiyahu, Uri

    2013-11-27

    The influence of macronutrient status on olive oil properties was studied for three years. Data were analyzed by a multivariate model considering N, P, K, and fruiting year as explanatory factors. Oil quality parameters were primarily associated with N concentration in leaves and fruits which increased with N in irrigation solution. The effect of P on oil quality was mainly indirect since increased P availability increased N accumulation. The potassium level had negligible effects. The oil phenolic content decreased linearly as a function of increased leaf N, indicating protein-phenol competition in leaves. The overall saturation level of the fatty acids decreased with fruit N, resulting in increased polyunsaturated fatty acids. Free fatty acids increased with increased levels of fruit N. High fruit load tended to reduce fruit N and subsequently improve oil quality. The effect of N on oil properties depended solely on its concentration in leaves or fruits, regardless of the cause.

  18. Analytical approaches for the characterization and identification of olive (Olea europaea) oil proteins.

    PubMed

    Esteve, Clara; D'Amato, Alfonsina; Marina, María Luisa; García, María Concepción; Righetti, Pier Giorgio

    2013-10-30

    Proteins in olive oil have been scarcely investigated probably due to the difficulty of working with such a lipidic matrix and the dramatically low abundance of proteins in this biological material. Additionally, this scarce information has generated contradictory results, thus requiring further investigations. This work treats this subject from a comprehensive point of view and proposes the use of different analytical approaches to delve into the characterization and identification of proteins in olive oil. Different extraction methodologies, including capture via combinational hexapeptide ligand libraries (CPLLs), were tried. A sequence of methodologies, starting with off-gel isoelectric focusing (IEF) followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) or high-performance liquid chromatography (HPLC) using an ultraperformance liquid chromatography (UPLC) column, was applied to profile proteins from olive seed, pulp, and oil. Besides this, and for the first time, a tentative identification of oil proteins by mass spectrometry has been attempted.

  19. Transcript Analysis and Regulative Events during Flower Development in Olive (Olea europaea L.).

    PubMed

    Alagna, Fiammetta; Cirilli, Marco; Galla, Giulio; Carbone, Fabrizio; Daddiego, Loretta; Facella, Paolo; Lopez, Loredana; Colao, Chiara; Mariotti, Roberto; Cultrera, Nicolò; Rossi, Martina; Barcaccia, Gianni; Baldoni, Luciana; Muleo, Rosario; Perrotta, Gaetano

    2016-01-01

    The identification and characterization of transcripts involved in flower organ development, plant reproduction and metabolism represent key steps in plant phenotypic and physiological pathways, and may generate high-quality transcript variants useful for the development of functional markers. This study was aimed at obtaining an extensive characterization of the olive flower transcripts, by providing sound information on the candidate MADS-box genes related to the ABC model of flower development and on the putative genetic and molecular determinants of ovary abortion and pollen-pistil interaction. The overall sequence data, obtained by pyrosequencing of four cDNA libraries from flowers at different developmental stages of three olive varieties with distinct reproductive features (Leccino, Frantoio and Dolce Agogia), included approximately 465,000 ESTs, which gave rise to more than 14,600 contigs and approximately 92,000 singletons. As many as 56,700 unigenes were successfully annotated and provided gene ontology insights into the structural organization and putative molecular function of sequenced transcripts and deduced proteins in the context of their corresponding biological processes. Differentially expressed genes with potential regulatory roles in biosynthetic pathways and metabolic networks during flower development were identified. The gene expression studies allowed us to select the candidate genes that play well-known molecular functions in a number of biosynthetic pathways and specific biological processes that affect olive reproduction. A sound understanding of gene functions and regulatory networks that characterize the olive flower is provided.

  20. Genetic Relationships Among Olive (Olea europaea L.) Cultivars Native to Turkey.

    PubMed

    Sakar, Ebru; Unver, Hulya; Bakir, Melike; Ulas, Mehmet; Sakar, Zeynep Mujde

    2016-08-01

    Olive is a widely cultivated, mainly in the Mediterranean region, and economically important fruit species used as both olive oil and table olive consumption. In Turkey, more than 50 olive cultivars have been authorized for commercial plantations, representing the developmental base for the olive industry. The aim of the present study was to identify genetic relationships among the most widely grown 27 olive cultivars in Turkey, using microsatellite or simple sequence repeat markers. Nine well-known foreign olive cultivars from different countries are also included in the study to compare the Turkish cultivars. To determine genetic relationship and diversity, 10 SSR loci (DCA3, DCA9, DCA15, DCA18, UDO4, UDO9, UDO11, UDO12, UDO24, UDO28) were used. Jaccard's similarity coefficient and the UPGMA method for cluster analysis were performed using the software NTSYSpc. The results showed that the number of alleles per locus ranging from 4 (UDO4, UDO9, UDO11, UDO12, DCA15) to 12 (DCA9) presenting high polymorphism. There were no identical cultivars. High similarity was shown by cultivars Maviand Adana topağı (0.754). The most genetically divergent cultivars, Domat-Meski (0.240) and Domat-NizipYağlık (0.245), were also identified.