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Sample records for anaerobic energy metabolism

  1. Metabolic energy-based modelling explains product yielding in anaerobic mixed culture fermentations.

    Directory of Open Access Journals (Sweden)

    Rebeca González-Cabaleiro

    Full Text Available The fermentation of glucose using microbial mixed cultures is of great interest given its potential to convert wastes into valuable products at low cost, however, the difficulties associated with the control of the process still pose important challenges for its industrial implementation. A deeper understanding of the fermentation process involving metabolic and biochemical principles is very necessary to overcome these difficulties. In this work a novel metabolic energy based model is presented that accurately predicts for the first time the experimentally observed changes in product spectrum with pH. The model predicts the observed shift towards formate production at high pH, accompanied with ethanol and acetate production. Acetate (accompanied with a more reduced product and butyrate are predicted main products at low pH. The production of propionate between pH 6 and 8 is also predicted. These results are mechanistically explained for the first time considering the impact that variable proton motive potential and active transport energy costs have in terms of energy harvest over different products yielding. The model results, in line with numerous reported experiments, validate the mechanistic and bioenergetics hypotheses that fermentative mixed cultures products yielding appears to be controlled by the principle of maximum energy harvest and the necessity of balancing the redox equivalents in absence of external electron acceptors.

  2. Aerobic and Anaerobic Starvation Metabolism in Methanotrophic Bacteria

    OpenAIRE

    Roslev, P.; King, G. M.

    1995-01-01

    The capacity for anaerobic metabolism of endogenous and selected exogenous substrates in carbon- and energy-starved methanotrophic bacteria was examined. The methanotrophic isolate strain WP 12 survived extended starvation under anoxic conditions while metabolizing 10-fold less endogenous substrate than did parallel cultures starved under oxic conditions. During aerobic starvation, the cell biomass decreased by 25% and protein and lipids were the preferred endogenous substrates. Aerobic prote...

  3. Effects of cadmium on anaerobic energy metabolism and mRNA expression during air exposure and recovery of an intertidal mollusk Crassostrea virginica

    International Nuclear Information System (INIS)

    Marine organisms are exposed to periodical oxygen deficiency and pollution stress in estuarine and coastal zones which may strongly affect their performance and survival. We studied the combined effects of exposure to a common pollutant, cadmium (Cd), and intermittent anoxia on anaerobic metabolism, energy status and mRNA expression of 13 genes involved in and/or controlled by the hypoxia inducible factor-1 (HIF-1) pathway in hepatopancreas of an intertidal bivalve, the eastern oyster Crassostrea virginica. In control oysters, prolonged anoxia resulted in a selective suppression of nitric oxide synthase (NOS) and upregulation of cytochrome c oxidase subunit IV (COX4) while the levels of other transcripts remained unchanged. During post-anoxic recovery, mRNA expression of hypoxia inducible factor-1α (HIF-1α) was elevated, phosphoenolpyruvate carboxykinase (PEPCK), NOS and LON protease suppressed, and mRNA expression of other studied genes not changed. Notably, most of the key glycolytic genes that are stimulated by HIF-1 in mammals, either remained unchanged or were downregulated in anoxic oysters suggesting a different mechanism of molecular response to oxygen deficiency. Patterns of transcriptional response during anoxia and reoxygenation were significantly altered by Cd exposure in a gene-specific manner. Anaerobic metabolism (indicated by accumulation of L-alanine, succinate and acetate during anoxia) was also suppressed in Cd-exposed oysters. In control oysters, ATP turnover rate (MATP) during anoxia was mostly sustained by anaerobic glycolysis with negligible contributions from ATP and PLA breakdown. In contrast, in Cd-exposed oysters ATP breakdown contributed significantly to anaerobic MATP. Thus, while control oysters could efficiently defend the ATP levels and tissue energy status during prolonged anoxia, Cd-exposed oysters experienced a disturbance in tissue energy balance indicated by the depletion of ATP, a rapid decline in adenylate energy charge and

  4. Anaerobic Metabolism: Linkages to Trace Gases and Aerobic Processes

    Science.gov (United States)

    Megonigal, J. P.; Hines, M. E.; Visscher, P. T.

    2003-12-01

    Life evolved and flourished in the absence of molecular oxygen (O2). As the O2 content of the atmosphere rose to the present level of 21% beginning about two billion years ago, anaerobic metabolism was gradually supplanted by aerobic metabolism. Anaerobic environments have persisted on Earth despite the transformation to an oxidized state because of the combined influence of water and organic matter. Molecular oxygen diffuses about 104 times more slowly through water than air, and organic matter supports a large biotic O2 demand that consumes the supply faster than it is replaced by diffusion. Such conditions exist in wetlands, rivers, estuaries, coastal marine sediments, aquifers, anoxic water columns, sewage digesters, landfills, the intestinal tracts of animals, and the rumen of herbivores. Anaerobic microsites are also embedded in oxic environments such as upland soils and marine water columns. Appreciable rates of aerobic respiration are restricted to areas that are in direct contact with air or those inhabited by organisms that produce O2.Rising atmospheric O2 reduced the global area of anaerobic habitat, but enhanced the overall rate of anaerobic metabolism (at least on an area basis) by increasing the supply of electron donors and acceptors. Organic carbon production increased dramatically, as did oxidized forms of nitrogen, manganese, iron, sulfur, and many other elements. In contemporary anaerobic ecosystems, nearly all of the reducing power is derived from photosynthesis, and most of it eventually returns to O2, the most electronegative electron acceptor that is abundant. This photosynthetically driven redox gradient has been thoroughly exploited by aerobic and anaerobic microorganisms for metabolism. The same is true of hydrothermal vents (Tunnicliffe, 1992) and some deep subsurface environments ( Chapelle et al., 2002), where thermal energy is the ultimate source of the reducing power.Although anaerobic habitats are currently a small fraction of Earth

  5. Anaerobic metabolism in Brassica seedlings

    Science.gov (United States)

    Park, Myoung-Ryoul; Hasenstein, Karl H.

    Germination typically depends on oxidative respiration. The lack of convection under space conditions may create hypoxic or conditions during seed germination. We investigated the effect of reduced oxygen on seed germination and metabolism to understand how metabolic constraints affect seed growth and responsiveness to reorientation. Germination was completely inhibited when seeds were imbibed in the absence of oxygen; germination occurred at 5% oxygen and higher levels. Adding oxygen after 72 h resulted in immediate germination (protrusion of the radicle). Hypoxia typically activates alcohol dehydrogenase (ADH, EC 1.1.1.1) and lactate dehydrogenase (LDH, EC 1.1.1.27) which produce ethanol and/or L-lactate, respectively. We report on the expression of ADH1 and LDH1, and changes in total soluble sugars, starch, pH, and L-lactate in seedlings grown at 28°C in 0, 2.5, 5, 10% and ambient (21%) oxygen conditions as controls. The highest consumption (lowest level) of sugars was seen at 0% oxygen but the lowest level of starch occurred 24 h after imbibition under ambient condition. Expression levels of ADH1 in ambient oxygen condition increased within 24 h but increased threefold under hypoxic conditions; LDH1 increased up to 8-fold under hypoxia compared to controls but ADH1 and LDH1 were less expressed as the oxygen levels increased. The intracellular pH of seeds decreased as the content of L-lactate increased for all oxygen concentrations. These results indicate that germination of Brassica is sensitive to oxygen levels and that oxygen availability during germination is an important factor for metabolic activities. (Supported by NASA grant NNX10AP91G)

  6. METABOLIC ENERGY GENERATION IN HYDROGENOSOMES OF THE ANAEROBIC FUNGUS NEOCALLIMASTIX - EVIDENCE FOR A FUNCTIONAL-RELATIONSHIP WITH MITOCHONDRIA

    NARCIS (Netherlands)

    MARVINSIKKEMA, FD; DRIESSEN, AJM; GOTTSCHAL, JC; PRINS, RA

    1994-01-01

    Anaerobic eukaryotes are often devoid of mitochondria but contain special organelles separated from the cytosol by a single (in fungi) or a double (in protozoa) membrane. Hydrogenosomes from the anaerobic fungus Neocallimastix sp. L2 are thought to catalyse the enzymic steps in the ATP-yielding meta

  7. Energetic and metabolic consequences of aerobic and an-aerobic ATP-production.

    NARCIS (Netherlands)

    Schreurs, V.V.A.M.; Aarts, M.J.; IJssennagger, N.; Hermans, J.; Hendriks, W.H.

    2007-01-01

    ATP, the currency of cellular energy metabolism, can be produced during aerobic and an-aerobic oxidation of metabolic substrates. The aerobic oxidation yields CO2 + H2O as metabolic end products while ATP is produced by oxidative phosphorylation in the mitochondria. Carbohydrate, protein and fat pro

  8. Anaerobic Metabolism and Bioremediation of Explosives-Contaminated Soil

    Science.gov (United States)

    Boopathy, Raj

    Nitroaromatic compounds pollute soil, water, and food via use of pesticides, plastics, pharmaceuticals, landfill dumping of industrial wastes, and the military use of explosives. Biotransformation of trinitrotoluene and other nitroaromatics by aerobic bacteria in the laboratory has been frequently reported, but the anaerobic bacterial metabolism of nitroaromatics has not been studied as extensively perhaps due to the difficulty in working with anaerobic cultures and the slow growth of anaerobes. Sulfate-reducing and methanogenic bacteria can metabolize nitroaromatic compounds under anaerobic conditions if appropriate electron donors and electron acceptors are present in the environment.

  9. Integrated Analysis of Protein Complexes and Regulatory Networks Involved in Anaerobic Energy Metabolism of Shewanella Oneidensis MR-1

    Energy Technology Data Exchange (ETDEWEB)

    Tiedje, James M.

    2005-06-01

    Anaerobic Nitrate Reduction. Nitrate is an extensive co-contaminant at some DOE sites making metal and radionuclide reduction problematic. Hence, we sought to better understand the nitrate reduction pathway and its control in S. oneidensis MR-1. It is not known whether the nitrate reduction is by denitrification or dissimilatory nitrate reduction into ammonium (DNRA). By both physiological and genetic evidence, we proved that DNRA is the nitrate reduction pathway in this organism. Using the complete genome sequence of S. oneidensis MR-1, we identified a gene encoding a periplasmic nitrate reductase based on its 72% sequence identity with the napA gene in E. coli. Anaerobic growth of MR-1 on nitrate was abolished in a site directed napA mutant, indicating that NapA is the only nitrate reductase present. The anaerobic expression of napA and nrfA, a homolog of the cytochrome b552 nitrite reductase in E. coli, increased with increasing nitrate concentration until a plateau was reached at 3 mM KNO3. This indicates that these genes are not repressed by increasing concentrations of nitrate. The reduction of nitrate can generate intermediates that can be toxic to the microorganism. To determine the genetic response of MR-1 to high concentrations of nitrate, DNA microarrays were used to obtain a complete gene expression profile of MR-1 at low (1 mM) versus high (40 mM) nitrate concentrations. Genes encoding transporters and efflux pumps were up-regulated, perhaps as a mechanism to export toxic compounds. In addition, the gene expression profile of MR-1, grown anaerobically with nitrate as the only electron acceptor, suggested that this dissimilatory pathway contributes to N assimilation. Hence the nitrate reduction pathway could serve a dual purpose. The role of EtrA, a homolog of Fnr (global anaerobic regulator in E. coli) was examined using an etrA deletion mutant we constructed, S. oneidensis EtrA7-1.

  10. Unifying concepts in anaerobic respiration: insights from dissimilatory sulfur metabolism.

    Science.gov (United States)

    Grein, Fabian; Ramos, Ana Raquel; Venceslau, Sofia S; Pereira, Inês A C

    2013-02-01

    Behind the versatile nature of prokaryotic energy metabolism is a set of redox proteins having a highly modular character. It has become increasingly recognized that a limited number of redox modules or building blocks appear grouped in different arrangements, giving rise to different proteins and functionalities. This modularity most likely reveals a common and ancient origin for these redox modules, and is obviously reflected in similar energy conservation mechanisms. The dissimilation of sulfur compounds was probably one of the earliest biological strategies used by primitive organisms to obtain energy. Here, we review some of the redox proteins involved in dissimilatory sulfur metabolism, focusing on sulfate reducing organisms, and highlight links between these proteins and others involved in different processes of anaerobic respiration. Noteworthy are links to the complex iron-sulfur molybdoenzyme family, and heterodisulfide reductases of methanogenic archaea. We discuss how chemiosmotic and electron bifurcation/confurcation may be involved in energy conservation during sulfate reduction, and how introduction of an additional module, multiheme cytochromes c, opens an alternative bioenergetic strategy that seems to increase metabolic versatility. Finally, we highlight new families of heterodisulfide reductase-related proteins from non-methanogenic organisms, which indicate a widespread distribution for these protein modules and may indicate a more general involvement of thiol/disulfide conversions in energy metabolism. This article is part of a Special Issue entitled: The evolutionary aspects of bioenergetic systems. PMID:22982583

  11. Contribution of anaerobic energy expenditure to whole body thermogenesis

    OpenAIRE

    Scott, Christopher B

    2005-01-01

    Heat production serves as the standard measurement for the determination of energy expenditure and efficiency in animals. Estimations of metabolic heat production have traditionally focused on gas exchange (oxygen uptake and carbon dioxide production) although direct heat measurements may include an anaerobic component particularly when carbohydrate is oxidized. Stoichiometric interpretations of the ratio of carbon dioxide production to oxygen uptake suggest that both anaerobic and aerobic he...

  12. Contribution of anaerobic energy expenditure to whole body thermogenesis

    OpenAIRE

    Scott Christopher B

    2005-01-01

    Abstract Heat production serves as the standard measurement for the determination of energy expenditure and efficiency in animals. Estimations of metabolic heat production have traditionally focused on gas exchange (oxygen uptake and carbon dioxide production) although direct heat measurements may include an anaerobic component particularly when carbohydrate is oxidized. Stoichiometric interpretations of the ratio of carbon dioxide production to oxygen uptake suggest that both anaerobic and a...

  13. Insights into the global regulation of anaerobic metabolism for improved biohydrogen production.

    Science.gov (United States)

    Lu, Yuan; Zhao, Hongxin; Zhang, Chong; Xing, Xin-Hui

    2016-01-01

    To improve the biohydrogen yield in bacterial dark fermentation, a new approach of global anaerobic regulation was introduced. Two cellular global regulators FNR and NarP were overexpressed in two model organisms: facultatively anaerobic Enterobacter aerogenes (Ea) and strictly anaerobic Clostridium paraputrificum (Cp). The overexpression of FNR and NarP greatly altered anaerobic metabolism and increased the hydrogen yield by 40%. Metabolic analysis showed that the global regulation caused more reducing environment inside the cell. To get a thorough understanding of the global metabolic regulation, more genes (fdhF, fhlA, ppk, Cb-fdh1, and Sc-fdh1) were overexpressed in different Ea and Cp mutants. For the first time, it demonstrated that there were approximately linear relationships between the relative change of hydrogen yield and the relative change of NADH yield or ATP yield. It implied that cellular reducing power and energy level played vital roles in the biohydrogen production. PMID:26476162

  14. Insights into the global regulation of anaerobic metabolism for improved biohydrogen production.

    Science.gov (United States)

    Lu, Yuan; Zhao, Hongxin; Zhang, Chong; Xing, Xin-Hui

    2016-01-01

    To improve the biohydrogen yield in bacterial dark fermentation, a new approach of global anaerobic regulation was introduced. Two cellular global regulators FNR and NarP were overexpressed in two model organisms: facultatively anaerobic Enterobacter aerogenes (Ea) and strictly anaerobic Clostridium paraputrificum (Cp). The overexpression of FNR and NarP greatly altered anaerobic metabolism and increased the hydrogen yield by 40%. Metabolic analysis showed that the global regulation caused more reducing environment inside the cell. To get a thorough understanding of the global metabolic regulation, more genes (fdhF, fhlA, ppk, Cb-fdh1, and Sc-fdh1) were overexpressed in different Ea and Cp mutants. For the first time, it demonstrated that there were approximately linear relationships between the relative change of hydrogen yield and the relative change of NADH yield or ATP yield. It implied that cellular reducing power and energy level played vital roles in the biohydrogen production.

  15. Contribution of anaerobic energy expenditure to whole body thermogenesis

    Directory of Open Access Journals (Sweden)

    Scott Christopher B

    2005-06-01

    Full Text Available Abstract Heat production serves as the standard measurement for the determination of energy expenditure and efficiency in animals. Estimations of metabolic heat production have traditionally focused on gas exchange (oxygen uptake and carbon dioxide production although direct heat measurements may include an anaerobic component particularly when carbohydrate is oxidized. Stoichiometric interpretations of the ratio of carbon dioxide production to oxygen uptake suggest that both anaerobic and aerobic heat production and, by inference, all energy expenditure – can be accounted for with a measurement of oxygen uptake as 21.1 kJ per liter of oxygen. This manuscript incorporates contemporary bioenergetic interpretations of anaerobic and aerobic ATP turnover to promote the independence of these disparate types of metabolic energy transfer: each has different reactants and products, uses dissimilar enzymes, involves different types of biochemical reactions, takes place in separate cellular compartments, exploits different types of gradients and ultimately each operates with distinct efficiency. The 21.1 kJ per liter of oxygen for carbohydrate oxidation includes a small anaerobic heat component as part of anaerobic energy transfer. Faster rates of ATP turnover that exceed mitochondrial respiration and that are supported by rapid glycolytic phosphorylation with lactate production result in heat production that is independent of oxygen uptake. Simultaneous direct and indirect calorimetry has revealed that this anaerobic heat does not disappear when lactate is later oxidized and so oxygen uptake does not adequately measure anaerobic efficiency or energy expenditure (as was suggested by the "oxygen debt" hypothesis. An estimate of anaerobic energy transfer supplements the measurement of oxygen uptake and may improve the interpretation of whole-body energy expenditure.

  16. Assessment of hydrogen metabolism in commercial anaerobic digesters.

    Science.gov (United States)

    Kern, Tobias; Theiss, Juliane; Röske, Kerstin; Rother, Michael

    2016-05-01

    Degradation of biomass in the absence of exogenous electron acceptors via anaerobic digestion involves a syntrophic association of a plethora of anaerobic microorganisms. The commercial application of this process is the large-scale production of biogas from renewable feedstock as an alternative to fossil fuels. After hydrolysis of polymers, monomers are fermented to short-chain fatty acids and alcohols, which are further oxidized to acetate. Carbon dioxide, molecular hydrogen (H2), and acetate generated during the process are converted to methane by methanogenic archaea. Since many of the metabolic pathways as well as the syntrophic interactions and dependencies during anaerobic digestion involve formation, utilization, or transfer of H2, its metabolism and the methanogenic population were assessed in various samples from three commercial biogas plants. Addition of H2 significantly increased the rate of methane formation, which suggested that hydrogenotrophic methanogenesis is not a rate-limiting step during biogas formation. Methanoculleus and Methanosarcina appeared to numerically dominate the archaeal population of the three digesters, but their proportion and the Bacteria-to-Archaea ratio did not correlate with the methane productivity. Instead, hydrogenase activity in cell-free extracts from digester sludge correlated with methane productivity in a positive fashion. Since most microorganisms involved in biogas formation contain this activity, it approximates the overall anaerobic metabolic activity and may, thus, be suitable for monitoring biogas reactor performance. PMID:26995607

  17. Redesigning Escherichia coli metabolism for anaerobic production of isobutanol.

    Science.gov (United States)

    Trinh, Cong T; Li, Johnny; Blanch, Harvey W; Clark, Douglas S

    2011-07-01

    Fermentation enables the production of reduced metabolites, such as the biofuels ethanol and butanol, from fermentable sugars. This work demonstrates a general approach for designing and constructing a production host that uses a heterologous pathway as an obligately fermentative pathway to produce reduced metabolites, specifically, the biofuel isobutanol. Elementary mode analysis was applied to design an Escherichia coli strain optimized for isobutanol production under strictly anaerobic conditions. The central metabolism of E. coli was decomposed into 38,219 functional, unique, and elementary modes (EMs). The model predictions revealed that during anaerobic growth E. coli cannot produce isobutanol as the sole fermentative product. By deleting 7 chromosomal genes, the total 38,219 EMs were constrained to 12 EMs, 6 of which can produce high yields of isobutanol in a range from 0.29 to 0.41 g isobutanol/g glucose under anaerobic conditions. The remaining 6 EMs rely primarily on the pyruvate dehydrogenase enzyme complex (PDHC) and are typically inhibited under anaerobic conditions. The redesigned E. coli strain was constrained to employ the anaerobic isobutanol pathways through deletion of 7 chromosomal genes, addition of 2 heterologous genes, and overexpression of 5 genes. Here we present the design, construction, and characterization of an isobutanol-producing E. coli strain to illustrate the approach. The model predictions are evaluated in relation to experimental data and strategies proposed to improve anaerobic isobutanol production. We also show that the endogenous alcohol/aldehyde dehydrogenase AdhE is the key enzyme responsible for the production of isobutanol and ethanol under anaerobic conditions. The glycolytic flux can be controlled to regulate the ratio of isobutanol to ethanol production.

  18. Slow swimming, fast strikes: effects of feeding behavior on scaling of anaerobic metabolism in epipelagic squid.

    Science.gov (United States)

    Trueblood, Lloyd A; Seibel, Brad A

    2014-08-01

    Many pelagic fishes engage prey at high speeds supported by high metabolic rates and anaerobic metabolic capacity. Epipelagic squids are reported to have among the highest metabolic rates in the oceans as a result of demanding foraging strategies and the use of jet propulsion, which is inherently inefficient. This study examined enzymatic proxies of anaerobic metabolism in two species of pelagic squid, Dosidicus gigas and Doryteuthis pealeii (Lesueur 1821), over a size range of six orders of magnitude. We hypothesized that activity of the anaerobically poised enzymes would be high and increase with size as in ecologically similar fishes. In contrast, we demonstrate that anaerobic metabolic capacity in these organisms scales negatively with body mass. We explored several cephalopod-specific traits, such as the use of tentacles to capture prey, body morphology and reduced relative prey size of adult squids, that may create a diminished reliance on anaerobically fueled burst activity during prey capture in large animals. PMID:25079893

  19. Carbohydrate oxidation coupled to Fe(III) reduction, a novel form of anaerobic metabolism.

    Science.gov (United States)

    Coates, J D; Councell, T; Ellis, D J; Lovley, D R

    1998-12-01

    An isolate, designated GC-29, that could incompletely oxidize glucose to acetate and carbon dioxide with Fe(III) serving as the electron acceptor was recovered from freshwater sediments of the Potomac River, Maryland. This metabolism yielded energy to support cell growth. Strain GC-29 is a facultatively anaerobic, gram-negative motile rod which, in addition to glucose, also used sucrose, lactate, pyruvate, yeast extract, casamino acids or H2 as alternative electron donors for Fe(III) reduction. Stain GC-29 could reduce NO3(-), Mn(IV), U(VI), fumarate, malate, S2O3(2-), and colloidal S0 as well as the humics analog, 2,6-anthraquinone disulfonate. Analysis of the almost complete 16S rRNA sequence indicated that strain GC-29 belongs in the Shewanella genus in the epsilon subdivision of the Proteobacteria. The name Shewanella saccharophilia is proposed. Shewanella saccharophilia differs from previously described fermentative microorganisms that metabolize glucose with the reduction of Fe(III) because it transfers significantly more electron equivalents to Fe(III); acetate and carbon dioxide are the only products of glucose metabolism; energy is conserved from Fe(III) reduction; and glucose is not metabolized in the absence of Fe(III). The metabolism of organisms like S. saccharophilia may account for the fact that glucose is metabolized primarily to acetate and carbon dioxide in a variety of sediments in which Fe(III) reduction is the terminal electron accepting process. PMID:16887653

  20. Metabolic interactions between methanogenic consortia and anaerobic respiring bacteria

    DEFF Research Database (Denmark)

    Stams, A.J.; Oude Elferink, S.J.; Westermann, Peter

    2003-01-01

    Most types of anaerobic respiration are able to outcompete methanogenic consortia for common substrates if the respective electron acceptors are present in sufficient amounts. Furthermore, several products or intermediate compounds formed by anaerobic respiring bacteria are toxic to methanogenic...

  1. How does oxygen inhibit central metabolism in the obligate anaerobe Bacteroides thetaiotaomicron.

    Science.gov (United States)

    Pan, N; Imlay, J A

    2001-03-01

    The molecular basis of obligate anaerobiosis is not well established. Bacteroides thetaiotaomicron is an opportunistic pathogen that cannot grow in fully aerobic habitats. Because microbial niches reflect features of energy-producing strategies, we suspected that aeration would interfere with its central metabolism. In anaerobic medium, this bacterium fermented carbohydrates to a mixture of succinate, propionate and acetate. When cultures were exposed to air, the formation of succinate and propionate ceased abruptly. In vitro analysis demonstrated that the fumarase of the succinate-propionate pathway contains an iron-sulphur cluster that is sensitive to superoxide. In vivo, fumarase activity fell to PFOR), the first enzyme in the acetate fermentation branch, to 3% of its anaerobic activity. This cluster-containing enzyme was damaged in vitro by molecular oxygen but not by superoxide. Thus, aerobic growth is precluded by the vulnerability of these iron-sulphur cluster enzymes to oxidation. Importantly, both enzymes were maintained in a stable, inactive form for long periods in aerobic cells; they were then rapidly repaired when the bacterium was returned to anaerobic medium. This result explains how this pathogen can easily recover from occasional exposure to oxygen. PMID:11260473

  2. Anaerobic metabolism in the N-limited green alga Selenastrum minutum. 3. Alanine is the product of anaerobic ammonium assimilation

    International Nuclear Information System (INIS)

    The authors have determined the flow of 15N into free amino acids of the N-limited green alga Selenastrum minutum (Naeg.) Collins after addition of 15NH4+ to aerobic or anaerobic cells. Under aerobic conditions, only a small proportion of the N assimilated was retained in the free amino acid pool. However, under anaerobic conditions almost all assimilated NH4+ accumulates in alanine. This is a unique feature of anaerobic NH4+ assimilation. The pathway of carbon flow to alanine results in the production of ATP and reductant which matches exactly the requirements of NH4+ assimilation. Alanine synthesis is therefore an excellent strategy to maintain energy and redox balance during anaerobic NH4+ assimilation

  3. Metabolic Regulation as a Consequence of Anaerobic 5-Methylthioadenosine Recycling in Rhodospirillum rubrum

    Science.gov (United States)

    North, Justin A.; Sriram, Jaya; Chourey, Karuna; Ecker, Christopher D.; Sharma, Ritin; Wildenthal, John A.; Hettich, Robert L.

    2016-01-01

    ABSTRACT Rhodospirillum rubrum possesses a novel oxygen-independent, aerobic methionine salvage pathway (MSP) for recycling methionine from 5-methylthioadenosine (MTA), the MTA-isoprenoid shunt. This organism can also metabolize MTA as a sulfur source under anaerobic conditions, suggesting that the MTA-isoprenoid shunt may also function anaerobically as well. In this study, deep proteomics profiling, directed metabolite analysis, and reverse transcriptase quantitative PCR (RT-qPCR) revealed metabolic changes in response to anaerobic growth on MTA versus sulfate as sole sulfur source. The abundance of protein levels associated with methionine transport, cell motility, and chemotaxis increased in the presence of MTA over that in the presence of sulfate. Purine salvage from MTA resulted primarily in hypoxanthine accumulation and a decrease in protein levels involved in GMP-to-AMP conversion to balance purine pools. Acyl coenzyme A (acyl-CoA) metabolic protein levels for lipid metabolism were lower in abundance, whereas poly-β-hydroxybutyrate synthesis and storage were increased nearly 10-fold. The known R. rubrum aerobic MSP was also shown to be upregulated, to function anaerobically, and to recycle MTA. This suggested that other organisms with gene homologues for the MTA-isoprenoid shunt may also possess a functioning anaerobic MSP. In support of our previous findings that ribulose-1,5-carboxylase/oxygenase (RubisCO) is required for an apparently purely anaerobic MSP, RubisCO transcript and protein levels both increased in abundance by over 10-fold in cells grown anaerobically on MTA over those in cells grown on sulfate, resulting in increased intracellular RubisCO activity. These results reveal for the first time global metabolic responses as a consequence of anaerobic MTA metabolism compared to using sulfate as the sulfur source. PMID:27406564

  4. Juvenile roach (Rutilus rutilus) increase their anaerobic metabolism in response to copper exposure in laboratory conditions.

    Science.gov (United States)

    Maes, Virginie; Betoulle, Stéphane; Jaffal, Ali; Dedourge-Geffard, Odile; Delahaut, Laurence; Geffard, Alain; Palluel, Olivier; Sanchez, Wilfried; Paris-Palacios, Séverine; Vettier, Aurélie; David, Elise

    2016-07-01

    This study aims to determine the potential impairment of cell energy synthesis processes (glycolysis and respiratory chain pathways) by copper in juvenile roach at different regulation levels by using a multi-marker approach. Juvenile roach were exposed to 0, 10, 50, and 100 µg/L of copper for 7 days in laboratory conditions. The glycolysis pathway was assessed by measuring the relative expression levels of 4 genes encoding glycolysis enzymes. The respiratory chain was studied by assessing the electron transport system and cytochrome c oxidase gene expression. Muscle mitochondria ultrastructure was studied, and antioxidant responses were measured. Furthermore, the main energy reserves-carbohydrates, lipids, and proteins-were measured, and cellular energy was evaluated by measuring ATP, ADP, AMP and IMP concentrations. This study revealed a disturbance of the cell energy metabolism due to copper exposure, with a significant decrease in adenylate energy charge in roach exposed to 10 μg/L of copper after 1 day. Moreover, ATP concentrations significantly decreased in roach exposed to 10 μg/L of copper after 1 day. This significant decrease persisted in roach exposed to 50 µg/L of copper after 7 days. AMP concentrations increased in all contaminated fish after 1 day of exposure. In parallel, the relative expression of 3 genes encoding for glycolysis enzymes increased in all contaminated fish after 1 day of copper exposure. Focusing on the respiratory chain, cytochrome c oxidase gene expression also increased in all contaminated fish at the two time-points. The activity of the electron transport system was not disturbed by copper, except in roach exposed to 100 µg/L of copper after 1 day. Copper induced a metabolic stress. Juvenile roach seemed to respond to the ensuing high energy demand by increasing their anaerobic metabolism, but the energy produced by the anaerobic metabolism is unable to compensate for the stress induced by copper after 7

  5. Apelin and energy metabolism

    Directory of Open Access Journals (Sweden)

    Chantal eBertrand

    2015-04-01

    Full Text Available A wide range of adipokines identified over the past years has allowed considering white adipose tissue as a secretory organ closely integrated into overall physiological and metabolic control. Apelin, an ubiquitous peptide was known to exert different physiological effects mainly on the cardiovascular system and the regulation of fluid homeostasis until its identification as an adipokine. This has increased its broad range of action and apelin now appears clearly as a new player in energy metabolism alongside leptin and adiponectin. Apelin has been shown to act on glucose and lipid metabolism but also to modulate insulin secretion. Moreover, different studies in both animals and humans have shown that plasma apelin concentrations are usually increased during obesity and type 2 diabetes. This mini-review will focus on the various systemic apelin effects on energy metabolism by addressing its mechanisms of action. The advances concerning the role of apelin in metabolic diseases in relation with the recent reports on apelin concentrations in obese and/or diabetic subjects will also be discussed.

  6. Identification of genes specifically required for the anaerobic metabolism of benzene in Geobacter metallireducens

    DEFF Research Database (Denmark)

    Zhang, Tian; Tremblay, Pier-Luc; Chaurasia, Akhilesh Kumar;

    2014-01-01

    Although the biochemical pathways for the anaerobic degradation of many of the hydrocarbon constituents in petroleum reservoirs have been elucidated, the mechanisms for anaerobic activation of benzene, a very stable molecule, are not known. Previous studies have demonstrated that Geobacter...... metallireducens can anaerobically oxidize benzene to carbon dioxide with Fe(III) as the sole electron acceptor and that phenol is an intermediate in benzene oxidation. In an attempt to identify enzymes that might be involved in the conversion of benzene to phenol, whole-genome gene transcript abundance...... was compared in cells metabolizing benzene and cells metabolizing phenol. Eleven genes had significantly higher transcript abundance in benzene-metabolizing cells. Five of these genes had annotations suggesting that they did not encode proteins that could be involved in benzene metabolism and were not further...

  7. Anaerobic digestion of organic solid waste for energy production

    OpenAIRE

    Nayono, Satoto Endar

    2009-01-01

    This study was carried out in order to evaluate the performance of anaerobic reactors treating OFMSW (organic fraction of municipal solid waste), especially in terms of its energy recovery, either by investigating the maximum organic loading rate or by co-digestion with other types of wastes for energy recovery. In order to reach the research purpose, several experiments such as characteristics examination of different organic solid wastes, which are potential substrates for anaerobic digestion.

  8. Identification of genes specifically required for the anaerobic metabolism of benzene in Geobacter metallireducens

    Directory of Open Access Journals (Sweden)

    Tian eZhang

    2014-05-01

    Full Text Available Although the biochemical pathways for the anaerobic degradation of many of the hydrocarbon constituents in petroleum reservoirs have been elucidated, the mechanisms for anaerobic activation of benzene, a very stable molecule, are not known. Previous studies have demonstrated that Geobacter metallireducens can anaerobically oxidize benzene to carbon dioxide with Fe(III as the sole electron acceptor and that phenol is an intermediate in benzene oxidation. In an attempt to identify enzymes that might be involved in the conversion of benzene to phenol, whole-genome gene transcript abundance was compared in cells metabolizing benzene and cells metabolizing phenol. Eleven genes had significantly higher transcript abundance in benzene-metabolizing cells. Five of these genes had annotations suggesting that they did not encode proteins that could be involved in benzene metabolism and were not further studied. Strains were constructed in which one of the remaining six genes was deleted. The strain in which the monocistronic gene Gmet 0232 was deleted metabolized phenol, but not benzene. Transcript abundance of the adjacent monocistronic gene, Gmet 0231, predicted to encode a zinc-containing oxidoreductase, was elevated in cells metabolizing benzene, although not at a statistically significant level. However, deleting Gmet 0231 also yielded a strain that could metabolize phenol, but not benzene. Although homologs of Gmet 0231 and Gmet 0232 are found in microorganisms not known to anaerobically metabolize benzene, the adjacent localization of these genes is unique to G. metallireducens. The discovery of genes that are specifically required for the metabolism of benzene, but not phenol in G. metallireducens is an important step in potentially identifying the mechanisms for anaerobic benzene activation.

  9. Effects of PCB 126 and cadmium on the anaerobic metabolism of the mussel Mytilus edulis L

    NARCIS (Netherlands)

    Eertman, R.H.M.; Zurburg, W.; Schipper, C.A.; Sandee, B.; Smaal, A.C.

    1996-01-01

    Exposure of mussels to PCB 126 and/or cadmium resulted in elevated anaerobic metabolic activity during 48 hr of aerial exposure. In mussels exposed to PCB 126 or cadmium this was achieved by an increased opine production. The largest increase was observed in PCB exposed mussels. In mussels that were

  10. Cold tolerance is unaffected by oxygen availability despite changes in anaerobic metabolism

    Science.gov (United States)

    Boardman, Leigh; Sørensen, Jesper G.; Koštál, Vladimír; Šimek, Petr; Terblanche, John S.

    2016-01-01

    Insect cold tolerance depends on their ability to withstand or repair perturbations in cellular homeostasis caused by low temperature stress. Decreased oxygen availability (hypoxia) can interact with low temperature tolerance, often improving insect survival. One mechanism proposed for such responses is that whole-animal cold tolerance is set by a transition to anaerobic metabolism. Here, we provide a test of this hypothesis in an insect model system (Thaumatotibia leucotreta) by experimental manipulation of oxygen availability while measuring metabolic rate, critical thermal minimum (CTmin), supercooling point and changes in 43 metabolites in moth larvae at three key timepoints (before, during and after chill coma). Furthermore, we determined the critical oxygen partial pressure below which metabolic rate was suppressed (c. 4.5 kPa). Results showed that altering oxygen availability did not affect (non-lethal) CTmin nor (lethal) supercooling point. Metabolomic profiling revealed the upregulation of anaerobic metabolites and alterations in concentrations of citric acid cycle intermediates during and after chill coma exposure. Hypoxia exacerbated the anaerobic metabolite responses induced by low temperatures. These results suggest that cold tolerance of T. leucotreta larvae is not set by oxygen limitation, and that anaerobic metabolism in these larvae may contribute to their ability to survive in necrotic fruit. PMID:27619175

  11. Exercise- and Hypoxia-Induced Anaerobic Metabolism and Recovery: A Student Laboratory Exercise Using Teleost Fish

    Science.gov (United States)

    Rees, B. B.; Boily, P.; Williamson, L. A. C.

    2009-01-01

    Anaerobic metabolism is recruited in vertebrates under conditions of intense exercise or lowered environmental oxygen availability (hypoxia), typically resulting in the accumulation of lactate in blood and tissues. Lactate will be cleared over time after the reoxygenation of tissues, eventually returning to control levels. Here, we present a…

  12. Anaerobic fermentation of glycerol in Paenibacillus macerans: metabolic pathways and environmental determinants.

    Science.gov (United States)

    Gupta, Ashutosh; Murarka, Abhishek; Campbell, Paul; Gonzalez, Ramon

    2009-09-01

    Paenibacillus macerans is one of the species with the broadest metabolic capabilities in the genus Paenibacillus, able to ferment hexoses, deoxyhexoses, pentoses, cellulose, and hemicellulose. However, little is known about glycerol metabolism in this organism, and some studies have reported that glycerol is not fermented. Despite these reports, we found that several P. macerans strains are capable of anaerobic fermentation of glycerol. One of these strains, P. macerans N234A, grew fermentatively on glycerol at a maximum specific growth rate of 0.40 h(-1) and was chosen for further characterization. The use of [U-13C]glycerol and further analysis of extracellular metabolites and proteinogenic amino acids via nuclear magnetic resonance (NMR) spectroscopy allowed identification of ethanol, formate, acetate, succinate, and 1,2-propanediol (1,2-PDO) as fermentation products and demonstrated that glycerol is incorporated into cellular components. A medium formulation with low concentrations of potassium and phosphate, cultivation at acidic pH, and the use of a CO2-enriched atmosphere stimulated glycerol fermentation and are proposed to be environmental determinants of this process. The pathways involved in glycerol utilization and synthesis of fermentation products were identified using NMR spectroscopy in combination with enzyme assays. Based on these studies, the synthesis of ethanol and 1,2-PDO is proposed to be a metabolic determinant of glycerol fermentation in P. macerans N234A. Conversion of glycerol to ethanol fulfills energy requirements by generating one molecule of ATP per molecule of ethanol synthesized. Conversion of glycerol to 1,2-PDO results in the consumption of reducing equivalents, thus facilitating redox balance. Given the availability, low price, and high degree of reduction of glycerol, the high metabolic rates exhibited by P. macerans N234A are of paramount importance for the production of fuels and chemicals. PMID:19617389

  13. Regulation and function of versatile aerobic and anaerobic respiratory metabolism in Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Hiroyuki eArai

    2011-05-01

    Full Text Available Pseudomonas aeruginosa is a ubiquitously distributed opportunistic pathogen that inhabits soil and water as well as animal-, human-, and plant-host-associated environments. The ubiquity would be attributed to its very versatile energy metabolism. P. aeruginosa has a highly branched respiratory chain terminated by multiple terminal oxidases and denitrification enzymes. Five terminal oxidases for aerobic respiration have been identified in the P. aeruginosa cells. Three of them, the cbb3-1 oxidase, the cbb3-2 oxidase, and the aa3 oxidase, are cytochrome c oxidases and the other two, the bo3 oxidase and the cyanide-insensitive oxidase, are quinol oxidases. Each oxidase has a specific affinity for oxygen, efficiency of energy coupling, and tolerance to various stresses such as cyanide and reactive nitrogen species. These terminal oxidases are used differentially according to the environmental conditions. P. aeruginosa also has a complete set of the denitrification enzymes that reduce nitrate to molecular nitrogen via nitrite, nitric oxide (NO, and nitrous oxide. These nitrogen oxides function as alternative electron acceptors and enable P. aeruginosa to grow under anaerobic conditions. One of the denitrification enzymes, NO reductase, is also expected to function for detoxification of NO produced by the host immune defense system. The control of the expression of these aerobic and anaerobic respiratory enzymes would contribute to the adaptation of P. aeruginosa to a wide range of environmental conditions including in the infected hosts. Characteristics of these respiratory enzymes and the regulatory system that controls the expression of the respiratory genes in the P. aeruginosa cells are overviewed in this article.

  14. SIRT1 and energy metabolism

    Institute of Scientific and Technical Information of China (English)

    Xiaoling Li

    2013-01-01

    Sirtuin 1 (SIRT1) is the most conserved mammalian NAD+-dependent protein deacetylase that has emerged as a key metabolic sensor in various metabolic tissues.In response to different environmental stimuli,SIRT1 directly links the cellular metabolic status to the chromatin structure and the regulation of gene expression,thereby modulating a variety of cellular processes such as energy metabolism and stress response.Recent studies have shown that SIRT1 controls both glucose and lipid metabolism in the liver,promotes fat mobilization and stimulates brown remodeling of the white fat in white adipose tissue,controls insulin secretion in the pancreas,senses nutrient availability in the hypothalamus,influences obesityinduced inflammation in macrophages,and modulates the activity of circadian clock in metabolic tissues.This review focuses on the role of SIRT1 in regulating energy metabolism at different metabolic tissues.

  15. Partitioning the metabolic scope: the importance of anaerobic metabolism and implications for the oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis

    Science.gov (United States)

    Ejbye-Ernst, Rasmus; Michaelsen, Thomas Y.; Tirsgaard, Bjørn; Wilson, Jonathan M.; Jensen, Lasse F.; Steffensen, John F.; Pertoldi, Cino; Aarestrup, Kim; Svendsen, Jon C.

    2016-01-01

    Ongoing climate change is predicted to affect the distribution and abundance of aquatic ectotherms owing to increasing constraints on organismal physiology, in particular involving the metabolic scope (MS) available for performance and fitness. The oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis prescribes MS as an overarching benchmark for fitness-related performance and assumes that any anaerobic contribution within the MS is insignificant. The MS is typically derived from respirometry by subtracting standard metabolic rate from the maximal metabolic rate; however, the methodology rarely accounts for anaerobic metabolism within the MS. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), this study tested for trade-offs (i) between aerobic and anaerobic components of locomotor performance; and (ii) between the corresponding components of the MS. Data collection involved measuring oxygen consumption rate at increasing swimming speeds, using the gait transition from steady to unsteady (burst-assisted) swimming to detect the onset of anaerobic metabolism. Results provided evidence of the locomotor performance trade-off, but only in S. aurata. In contrast, both species revealed significant negative correlations between aerobic and anaerobic components of the MS, indicating a trade-off where both components of the MS cannot be optimized simultaneously. Importantly, the fraction of the MS influenced by anaerobic metabolism was on average 24.3 and 26.1% in S. aurata and P. reticulata, respectively. These data highlight the importance of taking anaerobic metabolism into account when assessing effects of environmental variation on the MS, because the fraction where anaerobic metabolism occurs is a poor indicator of sustainable aerobic performance. Our results suggest that without accounting for anaerobic metabolism within the MS, studies involving the OCLTT hypothesis could overestimate the metabolic scope available for

  16. Partitioning the metabolic scope: the importance of anaerobic metabolism and implications for the oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis.

    Science.gov (United States)

    Ejbye-Ernst, Rasmus; Michaelsen, Thomas Y; Tirsgaard, Bjørn; Wilson, Jonathan M; Jensen, Lasse F; Steffensen, John F; Pertoldi, Cino; Aarestrup, Kim; Svendsen, Jon C

    2016-01-01

    Ongoing climate change is predicted to affect the distribution and abundance of aquatic ectotherms owing to increasing constraints on organismal physiology, in particular involving the metabolic scope (MS) available for performance and fitness. The oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis prescribes MS as an overarching benchmark for fitness-related performance and assumes that any anaerobic contribution within the MS is insignificant. The MS is typically derived from respirometry by subtracting standard metabolic rate from the maximal metabolic rate; however, the methodology rarely accounts for anaerobic metabolism within the MS. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), this study tested for trade-offs (i) between aerobic and anaerobic components of locomotor performance; and (ii) between the corresponding components of the MS. Data collection involved measuring oxygen consumption rate at increasing swimming speeds, using the gait transition from steady to unsteady (burst-assisted) swimming to detect the onset of anaerobic metabolism. Results provided evidence of the locomotor performance trade-off, but only in S. aurata. In contrast, both species revealed significant negative correlations between aerobic and anaerobic components of the MS, indicating a trade-off where both components of the MS cannot be optimized simultaneously. Importantly, the fraction of the MS influenced by anaerobic metabolism was on average 24.3 and 26.1% in S. aurata and P. reticulata, respectively. These data highlight the importance of taking anaerobic metabolism into account when assessing effects of environmental variation on the MS, because the fraction where anaerobic metabolism occurs is a poor indicator of sustainable aerobic performance. Our results suggest that without accounting for anaerobic metabolism within the MS, studies involving the OCLTT hypothesis could overestimate the metabolic scope available for

  17. Reprogramming of energy metabolism as a driver of aging.

    Science.gov (United States)

    Feng, Zhaoyang; Hanson, Richard W; Berger, Nathan A; Trubitsyn, Alexander

    2016-03-29

    Aging is characterized by progressive loss of cellular function and integrity. It has been thought to be driven by stochastic molecular damage. However, genetic and environmental maneuvers enhancing mitochondrial function or inhibiting glycolysis extend lifespan and promote healthy aging in many species. In post-fertile Caenorhabditis elegans, a progressive decline in phosphoenolpyruvate carboxykinase with age, and a reciprocal increase in pyruvate kinase shunt energy metabolism from oxidative metabolism to anaerobic glycolysis. This reduces the efficiency and total of energy generation. As a result, energy-dependent physical activity and other cellular functions decrease due to unmatched energy demand and supply. In return, decrease in physical activity accelerates this metabolic shift, forming a vicious cycle. This metabolic event is a determinant of aging, and is retarded by caloric restriction to counteract aging. In this review, we summarize these and other evidence supporting the idea that metabolic reprogramming is a driver of aging. We also suggest strategies to test this hypothesis. PMID:26919253

  18. Inhibition of microbial metabolism in anaerobic lagoons by selected sulfonamides, tetracyclines, lincomycin, and tylosin tartrate.

    Science.gov (United States)

    Loftin, Keith A; Henny, Cynthia; Adams, Craig D; Surampali, Rao; Mormile, Melanie R

    2005-04-01

    Antibiotics are used to maintain healthy livestock and to promote weight gain in concentrated animal feed operations. Antibiotics rarely are metabolized completely by livestock and, thus, are often present in livestock waste and in waste-treatment lagoons. The introduction of antibiotics into anaerobic lagoons commonly used for swine waste treatment has the potential for negative impacts on lagoon performance, which relies on a consortium of microbes ranging from fermentative microorganisms to methanogens. To address this concern, the effects of eight common veterinary antibiotics on anaerobic activity were studied. Anaerobic microcosms, prepared from freshly collected lagoon slurries, were amended with individual antibiotics at 10 mg/L for the initial screening study and at 1, 5, and 25 mg/L for the dose-response study. Monitored metabolic indicators included hydrogen, methane, and volatile fatty acid concentrations as well as chemical oxygen demand. The selected antibiotics significantly inhibited methane production relative to unamended controls, thus indicating that antibiotics at concentrations commonly found in swine lagoons can negatively impact anaerobic metabolism. Additionally, historical antibiotic usage seems to be a potential factor in affecting methane production. Specifically, less inhibition of methane production was noted in samples taken from the lagoon with a history of multiple-antibiotic use.

  19. Transcriptional regulation of metabolic pathways, alternative respiration and enterotoxin genes in anaerobic growth of Bacillus cereus ATCC 14579

    NARCIS (Netherlands)

    Voort, van der M.; Abee, T.

    2009-01-01

    Aims: To assess genes specifically activated during anaerobic growth that are involved in metabolism and pathogenesis of the foodborne pathogen Bacillus cereus. Methods and Results: Growth under anaerobic conditions in Brain Heart Infusion (BHI) broth revealed a reduced growth rate and lower yield a

  20. Partitioning the metabolic scope: the importance of anaerobic metabolism and implications for the oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis

    DEFF Research Database (Denmark)

    Ejbye-Ernst, Rasmus; Tirsgaard, B.; Michaelsen, Thomas Y.;

    2016-01-01

    , the methodology rarely accounts for anaerobic metabolism within the MS. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), this study tested for trade-offs (i) between aerobic and anaerobic components of locomotor performance; and (ii) between the corresponding components...

  1. Anaerobes beyond anaerobic digestion

    OpenAIRE

    Sousa, D. Z.; Pereira, M A; Alves, M.M.

    2009-01-01

    Anaerobic microorganisms are widespread in nature. Sediments, gastrointestinal tracks, volcanic vents, geothermal sources are examples of habitats where anaerobic metabolism prevail, in some cases at extreme temperature, pH and pressure conditions. In such microbial ecosystems waste of some is food for others in a true integrated structure. Anaerobic microorganisms are able to use a wide variety of organic and inorganic compounds. Recalcitrant compounds, such as hydrocarbons, a...

  2. Phylogenetic and Metabolic Diversity of Planctomycetes from Anaerobic, Sulfide- and Sulfur-Rich Zodletone Spring, Oklahoma▿

    OpenAIRE

    Elshahed, Mostafa S.; Youssef, Noha H.; Luo, Qingwei; Najar, Fares Z; Roe, Bruce A; Sisk, Tracy M.; Bühring, Solveig I.; Hinrichs, Kai-Uwe; Krumholz, Lee R

    2007-01-01

    We investigated the phylogenetic diversity and metabolic capabilities of members of the phylum Planctomycetes in the anaerobic, sulfide-saturated sediments of a mesophilic spring (Zodletone Spring) in southwestern Oklahoma. Culture-independent analyses of 16S rRNA gene sequences generated using Planctomycetes-biased primer pairs suggested that an extremely diverse community of Planctomycetes is present at the spring. Although sequences that are phylogenetically affiliated with cultured hetero...

  3. Sublethal Concentrations Of Antibiotics Cause Shift To Anaerobic Metabolism In Listeria Monocytogenes And Induce Phenotypes Linked To Antibiotic Tolerance

    DEFF Research Database (Denmark)

    Knudsen, Gitte Maegaard; Ng, Yin; Gram, Lone

    2015-01-01

    dehydrogenase gene lmo1634 and repression of alsA and lmo1992, which are involved in acetoin production leading to more ethanol and less acetoin production. This shift in central metabolism indicates a shift from aerobic to anaerobic metabolism, that could reduce oxidative stress and be a survival strategy...... investigation. The concentration of acetoin and ethanol are also currently under investigation. Conclusions: Consistent with other studies, we hypothesize that L. monocytogenes when exposed to antibiotics alters its metabolism from aerobic to anaerobic metabolism, and this could prepare the organism...

  4. Vulnerability of individual fish to capture by trawling is influenced by capacity for anaerobic metabolism.

    Science.gov (United States)

    Killen, Shaun S; Nati, Julie J H; Suski, Cory D

    2015-08-22

    The harvest of animals by humans may constitute one of the strongest evolutionary forces affecting wild populations. Vulnerability to harvest varies among individuals within species according to behavioural phenotypes, but we lack fundamental information regarding the physiological mechanisms underlying harvest-induced selection. It is unknown, for example, what physiological traits make some individual fish more susceptible to capture by commercial fisheries. Active fishing methods such as trawling pursue fish during harvest attempts, causing fish to use both aerobic steady-state swimming and anaerobic burst-type swimming to evade capture. Using simulated trawling procedures with schools of wild minnows Phoxinus phoxinus, we investigate two key questions to the study of fisheries-induced evolution that have been impossible to address using large-scale trawls: (i) are some individuals within a fish shoal consistently more susceptible to capture by trawling than others?; and (ii) if so, is this related to individual differences in swimming performance and metabolism? Results provide the first evidence of repeatable variation in susceptibility to trawling that is strongly related to anaerobic capacity and swimming ability. Maximum aerobic swim speed was also negatively correlated with vulnerability to trawling. Standard metabolic rate was highest among fish that were least vulnerable to trawling, but this relationship probably arose through correlations with anaerobic capacity. These results indicate that vulnerability to trawling is linked to anaerobic swimming performance and metabolic demand, drawing parallels with factors influencing susceptibility to natural predators. Selection on these traits by fisheries could induce shifts in the fundamental physiological makeup and function of descendent populations.

  5. Characteristics of anaerobic energy special performance athletes who specialize in judo.

    Directory of Open Access Journals (Sweden)

    Chistyakova M.A.

    2012-11-01

    Full Text Available The features of influence of hormonal status of sportswomen are considered on the change of anaerobic energy-supply of the special capacity. 13 sportswomen took part in research. It is rotined that for sportswomen the special capacity changed to on by the phases of menstrual cycle. It describable: by the increase of anaerobic possibilities (postovulatory and postmenstrual phase; by the decline of biotpower possibilities (menstrual, ovulatory, premenstrual phase, large metabolic tension of organism, high cost of vegetative functions. It is set that at most sportswomen the best indexes of the special capacity are marked in postmenstrual and postovulatory phases. Attention is accented on the necessity of ground of motive activity of having a special purpose orientation of sportswomen high qualification.

  6. Enhanced biogas yield from energy crops with rumen anaerobic fungi

    Energy Technology Data Exchange (ETDEWEB)

    Prochazka, Jindrich; Zabranska, Jana; Dohanyos, Michal [Department of Water Technology and Environmental Engineering, Faculty of Environmental Technology, Institute of Chemical Technology in Prague, Prague (Czech Republic); Mrazek, Jakub; Strosova, Lenka; Fliegerova, Katerina [Laboratory of Anaerobic Microbiology, Institute of Animal Physiology and Genetics, CAS, v.v.i., Prague (Czech Republic)

    2012-06-15

    Anaerobic fungi (AF) are able to degrade crop substrates with higher efficiency than commonly used anaerobic bacteria. The aim of this study was to investigate ways of use of rumen AF to improve biogas production from energy crops under laboratory conditions. In this study, strains of AF isolated from feces or rumen fluid of cows and deer were tested for their ability to integrate into the anaerobic bacterial ecosystem used for biogas production, in order to improve degradation of substrate polysaccharides and consequently the biogas yield. Batch culture, fed batch culture, and semicontinuous experiments have been performed using anaerobic sludge from pig slurry fermentation and different kinds of substrates (celluloses, maize, and grass silage) inoculated by different genera of AF. All experiments showed a positive effect of AF on the biogas yield and quality. AF improved the biogas production by 4-22%, depending on the substrate and AF species used. However, all the cultivation experiments indicated that rumen fungi do not show long-term survival in fermenters with digestate from pig slurry. The best results were achieved during fed batch experiment with fungal culture Anaeromyces (KF8), in which biogas production was enhanced during the whole experimental period of 140 days. This result has not been achieved in semicontinuous experiment, where increment in biogas production in fungal enriched reactor was only 4% after 42 days. (copyright 2012 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. The anaerobic linalool metabolism in Thauera linaloolentis 47 Lol

    OpenAIRE

    Marmulla, Robert; Cala, Edinson Puentes; Markert, Stephanie; Schweder, Thomas; Harder, Jens

    2016-01-01

    Background The betaproteobacterium Thauera linaloolentis 47LolT was isolated on the tertiary monoterpene alcohol (R,S)-linalool as sole carbon and energy source under denitrifying conditions. Growth experiments indicated the formation of geraniol and geranial. Thus, a 3,1-hydroxyl-Δ1-Δ2-mutase (linalool isomerase) activity may initiate the degradation, followed by enzymes of the acyclic terpene utilization (Atu) and leucine/isovalerate utilization (Liu) pathways that were extensively studied ...

  8. Lysine acetylation is a common post-translational modification of key metabolic pathway enzymes of the anaerobe Porphyromonas gingivalis.

    Science.gov (United States)

    Butler, Catherine A; Veith, Paul D; Nieto, Matthew F; Dashper, Stuart G; Reynolds, Eric C

    2015-10-14

    Porphyromonas gingivalis is a Gram-negative anaerobe considered to be a keystone pathogen in the development of the bacterial-associated inflammatory oral disease chronic periodontitis. Although post-translational modifications (PTMs) of proteins are commonly found to modify protein function in eukaryotes and prokaryotes, PTMs such as lysine acetylation have not been examined in P. gingivalis. Lysine acetylation is the addition of an acetyl group to a lysine which removes this amino acid's positive charge and can induce changes in a protein's secondary structure and reactivity. A proteomics based approach combining immune-affinity enrichment with high sensitivity Orbitrap mass spectrometry identified 130 lysine acetylated peptides from 92 P. gingivalis proteins. The majority of these peptides (71) were attributed to 45 proteins with predicted metabolic activity; these proteins could be mapped to several P. gingivalis metabolic pathways where enzymes catalysing sequential reactions within the same pathway were often found acetylated. In particular, the catabolic pathways of complex anaerobic fermentation of amino acids to produce energy had 12 enzymes lysine acetylated. The results suggest that lysine acetylation may be an important mechanism in metabolic regulation in P. gingivalis, which is vital for P. gingivalis survival and adaptation of its metabolism throughout infection. Statement of significance. Porphyromonas gingivalis is a keystone pathogen in the development of chronic periodontitis, an inflammatory disease of the supporting tissues of the teeth. The ability of the pathogen to induce dysbiosis and disease is related to an array of specific virulence factors and metabolic regulation that enables the bacterium to proliferate in an inflamed periodontal pocket. The mechanisms P. gingivalis uses to adapt to a changing and hostile environment are poorly understood and here we show, for the first time, that enzymes of critical metabolic pathways for energy

  9. Regulation of the anaerobic metabolism in Bacillus subtilis.

    Science.gov (United States)

    Härtig, Elisabeth; Jahn, Dieter

    2012-01-01

    The Gram-positive soil bacterium Bacillus subtilis encounters changing environmental conditions in its habitat. The access to oxygen determines the mode of energy generation. A complex regulatory network is employed to switch from oxygen respiration to nitrate respiration and various fermentative processes. During adaptation, oxygen depletion is sensed by the [4Fe-4S](2+) cluster containing Fnr and the two-component regulatory system ResDE consisting of the membrane-bound histidine kinase ResE and the cytoplasmic ResD regulator. Nitric oxide is the signal recognized by NsrR. Acetate formation and decreasing pH are measured via AlsR. Finally, Rex is responding to changes in the cellular NAD(+)/NADH ration. The fine-tuned interplay of these regulators at approximately 400 target gene promoters ensures efficient adaptation of the B. subtilis physiology. PMID:23046954

  10. One carbon metabolism in anaerobic bacteria: Regulation of carbon and electron flow during organic acid production

    Energy Technology Data Exchange (ETDEWEB)

    Zeikus, J.G.; Jain, M.

    1993-12-31

    The project deals with understanding the fundamental biochemical mechanisms that physiologically control and regulate carbon and electron flow in anaerobic chemosynthetic bacteria that couple metabolism of single carbon compounds and hydrogen to the production of organic acids (formic, acetic, butyric, and succinic) or methane. The authors compare the regulation of carbon dioxide and hydrogen metabolism by fermentation, enzyme, and electron carrier analysis using Butyribacterium methylotrophicum, Anaeroblospirillum succiniciproducens, Methanosarcina barkeri, and a newly isolated tri-culture composed of a syntrophic butyrate degrader strain IB, Methanosarcina mazei and Methanobacterium formicicum as model systems. To understand the regulation of hydrogen metabolism during butyrate production or acetate degradation, hydrogenase activity in B. methylotrophicum or M. barkeri is measured in relation to growth substrate and pH; hydrogenase is purified and characterized to investigate number of hydrogenases; their localization and functions; and, their sequences are determined. To understand the mechanism for catabolic CO{sub 2} fixation to succinate the PEP carboxykinase enzyme and gene of A. succiniciproducens are purified and characterized. Genetically engineered strains of Escherichia coli containing the phosphoenolpyruvate (PEP) carboxykinase gene are examined for their ability to produce succinate in high yield. To understand the mechanism of fatty acid degradation by syntrophic acetogens during mixed culture methanogenesis formate and hydrogen production are characterized by radio tracer studies. It is intended that these studies provide strategies to improve anaerobic fermentations used for the production of organic acids or methane and, new basic understanding on catabolic CO{sub 2} fixation mechanisms and on the function of hydrogenase in anaerobic bacteria.

  11. Characterizing the Anaerobic Response of Chlamydomonas reinhardtii by Quantitative Proteomics

    OpenAIRE

    Terashima, Mia; Specht, Michael; Naumann, Bianca; Hippler, Michael

    2010-01-01

    The versatile metabolism of the green alga Chlamydomonas reinhardtii is reflected in its complex response to anaerobic conditions. The anaerobic response is also remarkable in the context of renewable energy because C. reinhardtii is able to produce hydrogen under anaerobic conditions. To identify proteins involved during anaerobic acclimation as well as to localize proteins and pathways to the powerhouses of the cell, chloroplasts and mitochondria from C. reinhardtii in aerobic and anaerobic...

  12. In vitro metabolism of rebaudioside B, D, and M under anaerobic conditions: comparison with rebaudioside A.

    Science.gov (United States)

    Purkayastha, Sidd; Pugh, George; Lynch, Barry; Roberts, Ashley; Kwok, David; Tarka, Stanley M

    2014-03-01

    The hydrolysis of the steviol glycosides rebaudioside A, B, D, and M, as well as of steviolbioside (a metabolic intermediate) to steviol was evaluated in vitro using human fecal homogenates from healthy donors under anaerobic conditions. Incubation of each of the rebaudiosides resulted in rapid hydrolysis to steviol. Metabolism was complete within 24h, with the majority occurring within the first 8h. There were no clear differences in the rate or extent of metabolism of rebaudioside B, D, or M, relative to the comparative control rebaudioside A. The hydrolysis of samples containing 2.0mg/mL of each rebaudioside tended to take slightly longer than solutions containing 0.2mg/mL. There was no apparent gender differences in the amount of metabolism of any of the rebaudiosides, regardless of the concentrations tested. An intermediate in the hydrolysis of rebaudioside M to steviol, steviolbioside, was also found to be rapidly degraded to steviol. The results demonstrate that rebaudiosides B, D, and M are metabolized to steviol in the same manner as rebaudioside A. These data support the use of toxicology data available on steviol, and on steviol glycosides metabolized to steviol (i.e., rebaudioside A) to substantiate the safety of rebaudiosides B, D, and M. PMID:24361573

  13. Anaerobic digestion of organic solid waste for energy production

    Energy Technology Data Exchange (ETDEWEB)

    Nayono, Satoto Endar

    2010-07-01

    The total amount of municipal solid waste is continuously rising. Consequently, there are millions of tons of solid waste being produced every year which have to be safely disposed without any negative impact to the environment. On the other hand, as one of the driving forces for economic and social development the availability of energy in sufficient and sustainable amount has been becoming world's main interest. However, depending on the way the energy is produced, distributed and used, it may contribute to environmental problems such as water, land and air pollution or even global climate change. Anaerobic digestion as a pre-treatment prior to landfill disposal or composting offers several advantages, such as minimization of masses and volume, inactivation of biological and biochemical processes in order to avoid landfill-gas and odor emissions, reduction of landfill settlements and energy production in the form of methane. Therefore, anaerobic digestion of bio-degradable solid wastes can be considered an alternative option to improve the environment condition caused by organic solid waste and at the same time taking an advantage as an environmentally-friendly resource of energy. This study was carried out in order to evaluate the performance of anaerobic reactors treating OFMSW (organic fraction of municipal solid waste), especially in terms of its energy recovery, either by investigating the maximum organic loading rate or by co-digestion with other types of wastes for energy recovery. In order to reach the research purpose, several experimental activities such as characteristics examination of different organic solid wastes, which are potential substrates for anaerobic digestion and performance evaluation of the anaerobic reactors treating OFMSW were initiated. The Except for source-sorted OFMSW (later called biowaste), the substrates examined in this study were pressing leachate from an OFMSW composting plant (press water), source-sorted foodwaste

  14. Adenosine, Energy Metabolism, and Sleep

    Directory of Open Access Journals (Sweden)

    Tarja Porkka-Heiskanen

    2003-01-01

    Full Text Available While the exact function of sleep remains unknown, it is evident that sleep was developed early in phylogenesis and represents an ancient and vital strategy for survival. Several pieces of evidence suggest that the function of sleep is associated with energy metabolism, saving of energy, and replenishment of energy stores. Prolonged wakefulness induces signs of energy depletion in the brain, while experimentally induced, local energy depletion induces increase in sleep, similarly as would a period of prolonged wakefulness. The key molecule in the induction of sleep appears to be adenosine, which induces sleep locally in the basal forebrain.

  15. Phenotypic Diversity of Hydrogen Production in Chlorophycean Algae Reflects Distinct Anaerobic Metabolisms

    Energy Technology Data Exchange (ETDEWEB)

    Meuser, J. E.; Ananyev, G.; Wittig, L. E.; Kosourov, S.; Ghirardi, M. L.; Seibert, M.; Dismukes, G. C.; Posewitz, M. C.

    2009-01-01

    Several species of green algae use [FeFe]-hydrogenases to oxidize and/or produce H{sub 2} during anoxia. To further define unique aspects of algal hydrogenase activity, the well-studied anaerobic metabolisms of Chlamydomonas reinhardtii were compared with four strains of Chlamydomonas moewusii and a Lobochlamys culleus strain. In vivo and in vitro hydrogenase activity, starch accumulation/degradation, and anaerobic end product secretion were analyzed. The C. moewusii strains showed the most rapid induction of hydrogenase activity, congruent with high rates of starch catabolism, and anoxic metabolite accumulation. Intriguingly, we observed significant differences in morphology and hydrogenase activity in the C. moewusii strains examined, likely the result of long-term adaptation and/or genetic drift during culture maintenance. Of the C. moewusii strains examined, SAG 24.91 showed the highest in vitro hydrogenase activity. However, SAG 24.91 produced little H{sub 2} under conditions of sulfur limitation, which is likely a consequence of its inability to utilize exogenous acetate. In L. culleus, hydrogenase activity was minimal unless pulsed light was used to induce significant H2 photoproduction. Overall, our results demonstrate that unique anaerobic acclimation strategies have evolved in distinct green algae, resulting in differential levels of hydrogenase activity and species-specific patterns of NADH reoxidation during anoxia.

  16. Navigating wastewater energy recovery strategies: a life cycle comparison of anaerobic membrane bioreactor and conventional treatment systems with anaerobic digestion.

    Science.gov (United States)

    Smith, Adam L; Stadler, Lauren B; Cao, Ling; Love, Nancy G; Raskin, Lutgarde; Skerlos, Steven J

    2014-05-20

    The objective of this study was to evaluate emerging anaerobic membrane bioreactor (AnMBR) technology in comparison with conventional wastewater energy recovery technologies. Wastewater treatment process modeling and systems analyses were combined to evaluate the conditions under which AnMBR may produce more net energy and have lower life cycle environmental emissions than high rate activated sludge with anaerobic digestion (HRAS+AD), conventional activated sludge with anaerobic digestion (CAS+AD), and an aerobic membrane bioreactor with anaerobic digestion (AeMBR+AD). For medium strength domestic wastewater treatment under baseline assumptions at 15 °C, AnMBR recovered 49% more energy as biogas than HRAS+AD, the most energy positive conventional technology considered, but had significantly higher energy demands and environmental emissions. Global warming impacts associated with AnMBR were largely due to emissions of effluent dissolved methane. For high strength domestic wastewater treatment, AnMBR recovered 15% more net energy than HRAS+AD, and the environmental emissions gap between the two systems was reduced. Future developments of AnMBR technology in low energy fouling control, increased flux, and management of effluent methane emissions would make AnMBR competitive with HRAS+AD. Rapid advancements in AnMBR technology must continue to achieve its full economic and environmental potential as an energy recovery strategy for domestic wastewater. PMID:24742289

  17. Processes of malate catabolism during the anaerobic metabolism of grape berries

    International Nuclear Information System (INIS)

    In order to precise malate fate during the anaerobic metabolism of grape, malate-3-14C was injected into Carignan berries kept in darkness at 350C under carbon dioxide atmosphere. The injection of labelled malate was effected in presence or not of non-labelled oxalate which inhibits malic enzyme (EC I.I.I.40). The analyses of the samples fixed after 3 and 7 days anaerobiosis concerned the titration of various substrates, organic acids, amino-acids and glycolysis products, and the measuring of the NADP+-malic enzyme (EC I.I.I.40) and malate dehydrogenase (EC I.I.I.40). Radioactivity is mainly observed in ethanol, amino-butyrate the non-separated group glycerate-shikimate and succinate. Malic enzyme acts in the first sequence of a process leading from malate to ethanol. Alanin synthesis seems to be stimulated in presence of oxalate. The results obtained and some hypotheses presented in the literature induce to suggest a utilization scheme for malate in the anaerobic metabolism of grape

  18. Energy positive domestic wastewater treatment: the roles of anaerobic and phototrophic technologies.

    Science.gov (United States)

    Shoener, B D; Bradley, I M; Cusick, R D; Guest, J S

    2014-05-01

    The negative energy balance of wastewater treatment could be reversed if anaerobic technologies were implemented for organic carbon oxidation and phototrophic technologies were utilized for nutrient recovery. To characterize the potential for energy positive wastewater treatment by anaerobic and phototrophic biotechnologies we performed a comprehensive literature review and analysis, focusing on energy production (as kJ per capita per day and as kJ m(-3) of wastewater treated), energy consumption, and treatment efficacy. Anaerobic technologies included in this review were the anaerobic baffled reactor (ABR), anaerobic membrane bioreactor (AnMBR), anaerobic fluidized bed reactor (AFB), upflow anaerobic sludge blanket (UASB), anaerobic sequencing batch reactor (ASBR), microbial electrolysis cell (MEC), and microbial fuel cell (MFC). Phototrophic technologies included were the high rate algal pond (HRAP), photobioreactor (PBR), stirred tank reactor, waste stabilization pond (WSP), and algal turf scrubber (ATS). Average energy recovery efficiencies for anaerobic technologies ranged from 1.6% (MFC) to 47.5% (ABR). When including typical percent chemical oxygen demand (COD) removals by each technology, this range would equate to roughly 40-1200 kJ per capita per day or 110-3300 kJ m(-3) of treated wastewater. The average bioenergy feedstock production by phototrophic technologies ranged from 1200-4700 kJ per capita per day or 3400-13 000 kJ m(-3) (exceeding anaerobic technologies and, at times, the energetic content of the influent organic carbon), with usable energy production dependent upon downstream conversion to fuels. Energy consumption analysis showed that energy positive anaerobic wastewater treatment by emerging technologies would require significant reductions of parasitic losses from mechanical mixing and gas sparging. Technology targets and critical barriers for energy-producing technologies are identified, and the role of integrated anaerobic and

  19. Energy positive domestic wastewater treatment: the roles of anaerobic and phototrophic technologies

    KAUST Repository

    Shoener, B. D.

    2014-01-01

    The negative energy balance of wastewater treatment could be reversed if anaerobic technologies were implemented for organic carbon oxidation and phototrophic technologies were utilized for nutrient recovery. To characterize the potential for energy positive wastewater treatment by anaerobic and phototrophic biotechnologies we performed a comprehensive literature review and analysis, focusing on energy production (as kJ per capita per day and as kJ m-3 of wastewater treated), energy consumption, and treatment efficacy. Anaerobic technologies included in this review were the anaerobic baffled reactor (ABR), anaerobic membrane bioreactor (AnMBR), anaerobic fluidized bed reactor (AFB), upflow anaerobic sludge blanket (UASB), anaerobic sequencing batch reactor (ASBR), microbial electrolysis cell (MEC), and microbial fuel cell (MFC). Phototrophic technologies included were the high rate algal pond (HRAP), photobioreactor (PBR), stirred tank reactor, waste stabilization pond (WSP), and algal turf scrubber (ATS). Average energy recovery efficiencies for anaerobic technologies ranged from 1.6% (MFC) to 47.5% (ABR). When including typical percent chemical oxygen demand (COD) removals by each technology, this range would equate to roughly 40-1200 kJ per capita per day or 110-3300 kJ m-3 of treated wastewater. The average bioenergy feedstock production by phototrophic technologies ranged from 1200-4700 kJ per capita per day or 3400-13000 kJ m-3 (exceeding anaerobic technologies and, at times, the energetic content of the influent organic carbon), with usable energy production dependent upon downstream conversion to fuels. Energy consumption analysis showed that energy positive anaerobic wastewater treatment by emerging technologies would require significant reductions of parasitic losses from mechanical mixing and gas sparging. Technology targets and critical barriers for energy-producing technologies are identified, and the role of integrated anaerobic and phototrophic

  20. Hydrodynamic chronoamperometry for probing kinetics of anaerobic microbial metabolism--case study of Faecalibacterium prausnitzii.

    Science.gov (United States)

    Prévoteau, Antonin; Geirnaert, Annelies; Arends, Jan B A; Lannebère, Sylvain; Van de Wiele, Tom; Rabaey, Korneel

    2015-01-01

    Monitoring in vitro the metabolic activity of microorganisms aids bioprocesses and enables better understanding of microbial metabolism. Redox mediators can be used for this purpose via different electrochemical techniques that are either complex or only provide non-continuous data. Hydrodynamic chronoamperometry using a rotating disc electrode (RDE) can alleviate these issues but was seldom used and is poorly characterized. The kinetics of Faecalibacterium prausnitzii A2-165, a beneficial gut microbe, were determined using a RDE with riboflavin as redox probe. This butyrate producer anaerobically ferments glucose and reduces riboflavin whose continuous monitoring on a RDE provided highly accurate kinetic measurements of its metabolism, even at low cell densities. The metabolic reaction rate increased linearly over a broad range of cell concentrations (9 × 10(4) to 5 × 10(7) cells.mL(-1)). Apparent Michaelis-Menten kinetics was observed with respect to riboflavin (KM = 6 μM; kcat = 5.3 × 10(5) s(-1), at 37 °C) and glucose (KM = 6 μM; kcat = 2.4 × 10(5) s(-1)). The short temporal resolution allows continuous monitoring of fast cellular events such as kinetics inhibition with butyrate. Furthermore, we detected for the first time riboflavin reduction by another potential probiotic, Butyricicoccus pullicaecorum. The ability of the RDE for fast, accurate, simple and continuous measurements makes it an ad hoc tool for assessing bioprocesses at high resolution. PMID:26127013

  1. Metabolomics reveals stage-specific metabolic pathways of microbial communities in two-stage anaerobic fermentation of corn-stalk.

    Science.gov (United States)

    Yang, Dawei; Fan, Xiaolei; Shi, Xiaoshuang; Lian, Shujuan; Qiao, Jiangtao; Guo, Rongbo

    2014-07-01

    Analysis of intracellular metabolites is essential to delineate metabolic pathways of microbial communities for evaluation and optimization of anaerobic fermentation processes. The metabolomics are reported for a microbial community during two stages of anaerobic fermentation of corn stalk in a biogas digester using GC–MS. Acetonitrile/methanol/water (2:2:1, by vol) was the best extraction solvent for microbial community analysis because it yielded the largest number of peaks (>200), the highest mean summed value of identified metabolites (23) and the best reproducibility with a coefficient of variation of 30 % among four different extraction methods. Inter-stage comparison of metabolite profiles showed increased levels of sugars and sugar alcohols during methanogenesis and fatty acids during acidogenesis. Identification of stage-specific metabolic pathways using metabolomics can therefore assist in monitoring and optimization of the microbial community for increased biogas production during anaerobic fermentation. PMID:24658741

  2. Effects of lactone, ketone, and phenolic compounds on methane production and metabolic intermediates during anaerobic digestion.

    Science.gov (United States)

    Wikandari, Rachma; Sari, Noor Kartika; A'yun, Qurrotul; Millati, Ria; Cahyanto, Muhammad Nur; Niklasson, Claes; Taherzadeh, Mohammad J

    2015-02-01

    Fruit waste is a potential feedstock for biogas production. However, the presence of fruit flavors that have antimicrobial activity is a challenge for biogas production. Lactones, ketones, and phenolic compounds are among the several groups of fruit flavors that are present in many fruits. This work aimed to investigate the effects of two lactones, i.e., γ-hexalactone and γ-decalactone; two ketones, i.e., furaneol and mesifurane; and two phenolic compounds, i.e., quercetin and epicatechin on anaerobic digestion with a focus on methane production, biogas composition, and metabolic intermediates. Anaerobic digestion was performed in a batch glass digester incubated at 55 °C for 30 days. The flavor compounds were added at concentrations of 0.05, 0.5, and 5 g/L. The results show that the addition of γ-decalactone, quercetin, and epicathechin in the range of 0.5-5 g/L reduced the methane production by 50 % (MIC50). Methane content was reduced by 90 % with the addition of 5 g/L of γ-decalactone, quercetin, and epicathechin. Accumulation of acetic acid, together with an increase in carbon dioxide production, was observed. On the contrary, γ-hexalactone, furaneol, and mesifurane increased the methane production by 83-132 % at a concentration of 5 g/L.

  3. [Anaerobic biodegradation of tetrachloroethylene with methanol as co-metabolism substrate].

    Science.gov (United States)

    Li, Hui-di; Yang, Qi; Shang, Hai-tao

    2004-05-01

    Tetrachloroethylene (PCE) is biodegraded by reductive dechlorination in anaerobic condition. PCE degradation by methanol as co-metabolism substrate was studied. Results show that PCE was dechlorinated reductively to DCEs and TCE, probable VC and ethene. DCEs, VC and ethene are probably end products. It also shows that PCE, TCE degradation and TCE production fit in first order kinetics. Reaction rate constants for PCE and TCE were 0.8991 d(-1) and 0.068 d(-1) respectively. Half-live were 0.77 d and 10.19 d respectively. TCE production rate constant was 0.1333 d(-1). Rate constants show that PCE is degraded more rapidly than TCE. Production rate of TCE is higher than degradation rate of TCE, so TCE exists through the experiment.

  4. Time to exhaustion at anaerobic threshold in swimming rats: metabolic investigation.

    Science.gov (United States)

    Beck, W F; De Araujo, G G; Menezes Scariot, P P; Masselli dos Reis, I G; Gobatto, C A

    2014-01-01

    The purpose of this study was to determine the time to exhaustion (tlim) for swimming exercise at anaerobic threshold (AT) intensity in rats and to analyze metabolic consequences on serum and tissues levels. Eighteen rats were divided in control (CG) and exercised (EG) groups, being the former submitted to tlim. We analyzed the glycogen content of liver and ten skeletal muscles, as well as serum parameters. Parametric statistic was used with significance level at p exercise at individualized AT intensity promoted severe glycogen depletion for all tissues (mean of 78.05 % for all muscles and 89 % for liver). With substantial control of exercise intensity, our study establishes a useful rodent model that can be further explored, contributing to the advancement on knowledge and better understanding of exhaustion mechanisms. PMID:25573727

  5. Energy recovery from municipal solid waste in an anaerobic reactor.

    Science.gov (United States)

    Jeyapriya, S P; Saseetharan, M K

    2008-07-01

    Anaerobic digestion of municipal solid waste was carried out in the laboratory at room temperature to assess the bio-energy production from municipal solid waste (MSW) with high total solids content. The total biogas production from the municipal garbage was found to be 3.2 L in 120 days. The results from the biomethanation process showed that an increase in gas production was observed with increase in digestion period when the bioconversion parameters were found to be favorable for the production of gas. Changes in the parameters, such as pH, affected the production of gas significantly. Samples taken from the reactor at definite interval of time during the degradation process showed considerable reduction in total volatile solids, total carbon, total nitrogen and COD, etc. indicating the waste stabilization. PMID:19552079

  6. Hydrodynamic chronoamperometry for probing kinetics of anaerobic microbial metabolism - case study of Faecalibacterium prausnitzii

    Science.gov (United States)

    Prévoteau, Antonin; Geirnaert, Annelies; Arends, Jan B. A.; Lannebère, Sylvain; van de Wiele, Tom; Rabaey, Korneel

    2015-07-01

    Monitoring in vitro the metabolic activity of microorganisms aids bioprocesses and enables better understanding of microbial metabolism. Redox mediators can be used for this purpose via different electrochemical techniques that are either complex or only provide non-continuous data. Hydrodynamic chronoamperometry using a rotating disc electrode (RDE) can alleviate these issues but was seldom used and is poorly characterized. The kinetics of Faecalibacterium prausnitzii A2-165, a beneficial gut microbe, were determined using a RDE with riboflavin as redox probe. This butyrate producer anaerobically ferments glucose and reduces riboflavin whose continuous monitoring on a RDE provided highly accurate kinetic measurements of its metabolism, even at low cell densities. The metabolic reaction rate increased linearly over a broad range of cell concentrations (9 × 104 to 5 × 107 cells.mL-1). Apparent Michaelis-Menten kinetics was observed with respect to riboflavin (KM = 6 μM kcat = 5.3×105 s-1, at 37 °C) and glucose (KM = 6 μM kcat = 2.4 × 105 s-1). The short temporal resolution allows continuous monitoring of fast cellular events such as kinetics inhibition with butyrate. Furthermore, we detected for the first time riboflavin reduction by another potential probiotic, Butyricicoccus pullicaecorum. The ability of the RDE for fast, accurate, simple and continuous measurements makes it an ad hoc tool for assessing bioprocesses at high resolution.

  7. Energy balance of a two-phase anaerobic digestion process for energy crops

    Energy Technology Data Exchange (ETDEWEB)

    Zielonka, Simon; Lemmer, Andreas; Oechsner, Hans; Jungbluth, Thomas [University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Stuttgart (Germany)

    2010-12-15

    This article deals with the digestion of energy crops in a two-phase biogas process based on an anaerobic leach-bed reactor combined with an anaerobic filter. The biogas process is a microbiological conversion of biomass into methane and carbon dioxide. This process is carried out by different microorganisms and can be divided into four steps which normally take place in only one digester. To be able to digest difficult energy crops by mono-digestion and to meet the different needs of the several bacteria, which take part in the four-step process of the methane production, the process was divided into two phases: (i) an anaerobic batch leach-bed phase, where the leachate was produced and (ii) an anaerobic filter, where the organic fraction of the leachate was converted into biogas. Considering the results of the experiments, the two-phase digestion of energy crops exhibited stable digestion behavior. No biological imbalance of the process, e.g. due to a sudden change of substrate, was detected either in the leach bed or in the anaerobic filter. Variation in suitability for two-phase fermentation with an anaerobic batch leach-bed reactor was observed for various substrates. The different substrates varied in their influence on acid formation and concentration as well as an influence on the course of the pH value. Therefore, an effect on the distribution of energy to the phases could be observed. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Accumulibacter clades Type I and II performing kinetically different glycogen-accumulating organisms metabolisms for anaerobic substrate uptake.

    Science.gov (United States)

    Welles, L; Tian, W D; Saad, S; Abbas, B; Lopez-Vazquez, C M; Hooijmans, C M; van Loosdrecht, M C M; Brdjanovic, D

    2015-10-15

    The anaerobic acetate (HAc) uptake stoichiometry of phosphorus-accumulating organisms (PAO) in enhanced biological phosphorus removal (EBPR) systems has been an extensive subject of study due to the highly variable reported stoichiometric values (e.g. anaerobic P-release/HAc-uptake ratios ranging from 0.01 up to 0.93 P-mol/C-mol). Often, such differences have been explained by the different applied operating conditions (e.g. pH) or occurrence of glycogen-accumulating organisms (GAO). The present study investigated the ability of biomass highly enriched with specific PAO clades ('Candidatus Accumulibacter phosphatis' Clade I and II, hereafter PAO I and PAO II) to adopt a GAO metabolism. Based on long-term experiments, when Poly-P is not stoichiometrically limiting for the anaerobic VFA uptake, PAO I performed the typical PAO metabolism (with a P/HAc ratio of 0.64 P-mol/C-mol); whereas PAO II performed a mixed PAO-GAO metabolism (showing a P/HAc ratio of 0.22 P-mol/C-mol). In short-term batch tests, both PAO I and II gradually shifted their metabolism to a GAO metabolism when the Poly-P content decreased, but the HAc-uptake rate of PAO I was 4 times lower than that of PAO II, indicating that PAO II has a strong competitive advantage over PAO I when Poly-P is stoichiometrically limiting the VFA uptake. Thus, metabolic flexibility of PAO clades as well as their intrinsic differences are additional factors leading to the controversial anaerobic stoichiometry and kinetic rates observed in previous studies. From a practical perspective, the dominant type of PAO prevailing in full-scale EBPR systems may affect the P-release processes for biological or combined biological and chemical P-removal and recovery and consequently the process performance. PMID:26189167

  9. Improved Energy Recovery by Anaerobic Grey Water Sludge Treatment with Black Water

    NARCIS (Netherlands)

    Tervahauta, T.H.; Bryant, I.M.; Hernandez Leal, L.; Buisman, C.J.N.; Zeeman, G.

    2014-01-01

    This study presents the potential of combining anaerobic grey water sludge treatment with black water in an up-flow anaerobic sludge blanket (UASB) reactor to improve energy recovery within source-separated sanitation concepts. Black water and the mixture of black water and grey water sludge were co

  10. Submerged anaerobic membrane bioreactor for wastewater treatment and energy generation.

    Science.gov (United States)

    Bornare, J B; Adhyapak, U S; Minde, G P; Kalyan Raman, V; Sapkal, V S; Sapkal, R S

    2015-01-01

    Compared with conventional wastewater treatment processes, membrane bioreactors (MBRs) offer several advantages including high biodegradation efficiency, excellent effluent quality and smaller footprint. However, it has some limitations on account of its energy intensive operation. In recent years, there has been growing interest in use of anaerobic membrane bioreactors (AnMBRs) due to their potential advantages over aerobic systems, which include low sludge production and energy generation in terms of biogas. The aim of this study was to evaluate the performance of a submerged AnMBR for the treatment of synthetic wastewater having 4,759 mg/l chemical oxygen demand (COD). The COD removal efficiency was over 95% during the performance evaluation study. Treated effluent with COD concentration of 231 mg/l was obtained for 25.5 hours hydraulic retention time. The obtained total organic carbon concentrations in feed and permeate were 1,812 mg/l and 89 mg/l, respectively. An average biogas generation and yield were 25.77 l/d and 0.36 m3/kg COD, respectively. Evolution of trans-membrane pressure (TMP) as a function of time was studied and an average TMP of 15 kPa was found suitable to achieve membrane flux of 12.17 l/(m2h). Almost weekly back-flow chemical cleaning of the membrane was found necessary to control TMP within the permissible limit of 20 kPa. PMID:26038930

  11. Metabolism of toxic pyrrolizidine alkaloids from tansy ragwort (Senecio jacobaea) in ovine ruminal fluid under anaerobic conditions.

    Science.gov (United States)

    Craig, A M; Latham, C J; Blythe, L L; Schmotzer, W B; O'Connor, O A

    1992-01-01

    The ability of ovine ruminal fluid to metabolize pyrrolizidine alkaloid (PA) from Senecio jacobaea under anaerobic conditions was evaluated. Four fistulated sheep fed PA served as individual sources of ruminal fluid, which was incubated in a defined minimal salts medium under two different anaerobic conditions, denitrifying and methanogenic. Anaerobic cultures amended with ovine ruminal fluids (20%), PA (100 micrograms/ml), and a defined minimal salts medium were monitored for a period of several days. These cultures revealed that while PA was not depleted in sterile, autoclaved controls or under denitrifying conditions, it was metabolized during periods of active methanogenesis under methanogenic conditions. In addition, samples of ruminal fluid were separated by differential centrifugation under anaerobic conditions, and the resultant supernatants were tested for their ability to metabolize PA as compared with those of the respective uncentrifuged control fluids. Uncentrifuged controls exhibited a PA depletion rate of -4.04 +/- 0.17 micrograms of PA per ml per h. Supernatants 1 (centrifuged at 41 x g for 2 min), 2 (centrifuged at 166 x g for 5 min), and 3 (centrifuged at 1,500 x g for 10 min) exhibited significantly slower depletion rates, with slopes of data representing -1.64 +/- 0.16, -1.44 +/- 0.16, and -1.48 +/- 0.16 micrograms of PA metabolized per ml per h, respectively, demonstrating no statistically significant difference among the supernatant cultures. Microscopic evaluations revealed that protozoa were present in the control whole ruminal fluid and to a lesser extent in supernatant 1, while supernatants 2 and 3 contained only bacteria.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1444382

  12. Complete genome of Ignavibacterium album, a metabolically versatile, flagellated, facultative anaerobe from the phylum Chlorobi

    Directory of Open Access Journals (Sweden)

    Zhenfeng eLiu

    2012-05-01

    Full Text Available Prior to the recent discovery of Ignavibacterium album (I. album, anaerobic photoautotrophic green sulfur bacteria (GSB were the only cultivated members of the bacterial phylum Chlorobi. In contrast to GSB, sequence analysis of the 3.7-Mbp genome of I. album shows that this recently described member of the phylum Chlorobi is a chemoheterotroph with a versatile metabolism. I. album lacks genes for photosynthesis and sulfur oxidation but has a full set of genes for flagella and chemotaxis. The occurrence of genes for multiple electron transfer complexes suggests that I. album is capable of organoheterotrophy under both oxic and anoxic conditions. The occurrence of genes encoding enzymes for CO2 fixation as well as other enzymes of the reductive TCA cycle suggests that mixotrophy may be possible under certain growth conditions. However, known biosynthetic pathways for several amino acids are incomplete; this suggests that I. album is dependent upon on exogenous sources of these metabolites or employs novel biosynthetic pathways. Comparisons of I. album and other members of the phylum Chlorobi suggest that the physiology of the ancestors of this phylum might have been quite different from that of modern GSB.

  13. Effect of copper on liver key enzymes of anaerobic glucose metabolism from freshwater tropical fish Prochilodus lineatus.

    Science.gov (United States)

    Carvalho, Cleoni dos Santos; Fernandes, Marisa Narciso

    2008-11-01

    We investigated the effect of copper on liver key enzymes of the anaerobic glucose metabolism (hexokinase, HK; phosphofructokinase, PFK; pyruvate kinase, PK; lactate dehydrogenase, LDH) as well as of the pentose pathway (glycose-6-phosphate dehydrogenase, G6PDH) from the fish Prochilodus lineatus. The fish were acclimated at either 20 degrees C or 30 degrees C at pH 7.0, transferred to water at pH 4.5 or 8.0, and exposed to 96 h-CL(50) copper concentrations. Copper accumulation in liver was higher in fish acclimated at 20 degrees C and maintained in water pH 8.0. Three-way analysis of variance revealed a significant effect of temperature on all enzymes, a significant effect of pH on all enzymes except for PK, and a significant effect of copper on only PFK, and LDH in pH 4.5 at 20 degrees C and, at 30 degrees C, on PFK and PK at pH 4.5 and 8.0, HK at pH 4.5 and G6PDH at pH 8.0. There were significant interactions between treatments for many enzymes. These changes suggest that the activity of enzymes in question is modified by a change in ambient water. At least at 30 degrees C, the overall reduction in the glycolytic enzyme activities of copper-exposed fish seems to reduce energy availability via glucose metabolism, thereby contributing to enhance copper toxic effects.

  14. In situ detection of anaerobic alkane metabolites in subsurface environments

    Directory of Open Access Journals (Sweden)

    Lisa eGieg

    2013-06-01

    Full Text Available Alkanes comprise a substantial fraction of crude oil and refined fuels. As such, they are prevalent within deep subsurface fossil fuel deposits and in shallow subsurface environments such as aquifers that are contaminated with hydrocarbons. These environments are typically anaerobic, and host diverse microbial communities that can potentially use alkanes as substrates. Anaerobic alkane biodegradation has been reported to occur under nitrate-reducing, sulfate-reducing, and methanogenic conditions. Elucidating the pathways of anaerobic alkane metabolism has been of interest in order to understand how microbes can be used to remediate contaminated sites. Alkane activation primarily occurs by addition to fumarate, yielding alkylsuccinates, unique anaerobic metabolites that can be used to indicate in situ anaerobic alkane metabolism. These metabolites have been detected in hydrocarbon-contaminated shallow aquifers, offering strong evidence for intrinsic anaerobic bioremediation. Recently, studies have also revealed that alkylsuccinates are present in oil and coal seam production waters, indicating that anaerobic microbial communities can utilize alkanes in these deeper subsurface environments. In many crude oil reservoirs, the in situ anaerobic metabolism of hydrocarbons such as alkanes may be contibuting to modern-day detrimental effects such as oilfield souring, or may lead to more benefical technologies such as enhanced energy recovery from mature oilfields. In this review, we briefly describe the key metabolic pathways for anaerobic alkane (including n-alkanes, isoalkanes, and cyclic alkanes metabolism and highlight several field reports wherein alkylsuccinates have provided evidence for anaerobic in situ alkane metabolism in shallow and deep subsurface environments.

  15. The anaerobic linalool metabolism in the betaproteobacteria Castellaniella defragrans 65Phen and Thauera linaloolentis 47Lol

    OpenAIRE

    Marmulla, Robert

    2015-01-01

    The betaproteobacteria Castellaniella defragrans 65Phen and Thauera linaloolentis 47Lol were recently isolated on monoterpenes as sole carbon and energy source under denitrifying conditions. C. defragrans 65Phen metabolizes the hydrocarbon monoterpene beta-myrcene. Its activation is catalyzed by the bifunctional enzyme linalool dehydratase/isomerase. In the presented work, an improved purification protocol was developed to yield high amounts of protein for structural analysis by X-ray crystal...

  16. Anaerobic hydrocarbon and fatty acid metabolism by syntrophic bacteria and their impact on carbon steel corrosion

    Directory of Open Access Journals (Sweden)

    Christopher Neil Lyles

    2014-04-01

    Full Text Available The microbial metabolism of hydrocarbons is increasingly associated with the corrosion of carbon steel in sulfate-rich marine waters. However, how such transformations influence metal biocorrosion in the absence of an electron acceptor is not fully recognized. We grew a marine alkane-utilizing, sulfate-reducing bacterium, Desulfoglaeba alkanexedens, with either sulfate or Methanospirillum hungatei as electron acceptors, and tested the ability of the cultures to catalyze metal corrosion. Axenically, D. alkanexedens had a higher instantaneous corrosion rate and produced more pits in carbon steel coupons than when the same organism was grown in syntrophic co-culture with the methanogen. Since anaerobic hydrocarbon biodegradation pathways converge on fatty acid intermediates, the corrosive ability of a known fatty acid-oxidizing syntrophic bacterium, Syntrophus aciditrophicus was compared when grown in pure culture or in co-culture with a H2-utilizing sulfate-reducing bacterium (Desulfovibrio sp., strain G11 or a methanogen (M. hungatei. The instantaneous corrosion rates in the cultures were not substantially different, but the syntrophic, sulfate-reducing co-culture produced more pits in coupons than other combinations of microorganisms. Lactate-grown cultures of strain G11 had higher instantaneous corrosion rates and coupon pitting compared to the same organism cultured with hydrogen as an electron donor. Thus, if sulfate is available as an electron acceptor, the same microbial assemblages produce sulfide and low molecular weight organic acids that exacerbated biocorrosion. Despite these trends, a surprisingly high degree of variation was encountered with the corrosion assessments. Differences in biomass, initial substrate concentration, rates of microbial activity or the degree of end product formation did not account for the variations. We are forced to ascribe such differences to the metallurgical properties of the coupons.

  17. Anaerobic hydrocarbon and fatty acid metabolism by syntrophic bacteria and their impact on carbon steel corrosion.

    Science.gov (United States)

    Lyles, Christopher N; Le, Huynh M; Beasley, William Howard; McInerney, Michael J; Suflita, Joseph M

    2014-01-01

    The microbial metabolism of hydrocarbons is increasingly associated with the corrosion of carbon steel in sulfate-rich marine waters. However, how such transformations influence metal biocorrosion in the absence of an electron acceptor is not fully recognized. We grew a marine alkane-utilizing, sulfate-reducing bacterium, Desulfoglaeba alkanexedens, with either sulfate or Methanospirillum hungatei as electron acceptors, and tested the ability of the cultures to catalyze metal corrosion. Axenically, D. alkanexedens had a higher instantaneous corrosion rate and produced more pits in carbon steel coupons than when the same organism was grown in syntrophic co-culture with the methanogen. Since anaerobic hydrocarbon biodegradation pathways converge on fatty acid intermediates, the corrosive ability of a known fatty acid-oxidizing syntrophic bacterium, Syntrophus aciditrophicus was compared when grown in pure culture or in co-culture with a H2-utilizing sulfate-reducing bacterium (Desulfovibrio sp., strain G11) or a methanogen (M. hungatei). The instantaneous corrosion rates in the cultures were not substantially different, but the syntrophic, sulfate-reducing co-culture produced more pits in coupons than other combinations of microorganisms. Lactate-grown cultures of strain G11 had higher instantaneous corrosion rates and coupon pitting compared to the same organism cultured with hydrogen as an electron donor. Thus, if sulfate is available as an electron acceptor, the same microbial assemblages produce sulfide and low molecular weight organic acids that exacerbated biocorrosion. Despite these trends, a surprisingly high degree of variation was encountered with the corrosion assessments. Differences in biomass, initial substrate concentration, rates of microbial activity or the degree of end product formation did not account for the variations. We are forced to ascribe such differences to the metallurgical properties of the coupons.

  18. Sublethal Concentrations of Antibiotics Cause Shift to Anaerobic Metabolism in Listeria monocytogenes and Induce Phenotypes Linked to Antibiotic Tolerance

    DEFF Research Database (Denmark)

    Knudsen, Gitte Maegaard; Fromberg, Arvid; Ng, Yin;

    2016-01-01

    antibiotic concentrations would affect the bacterial physiology and induce antibiotic tolerance. Transcriptomic analyses demonstrated that each of the four antibiotics tested caused an antibiotic-specific gene expression pattern related to mode-of-action of the particular antibiotic. All four antibiotics...... caused the same changes in expression of several metabolic genes indicating a shift from aerobic to anaerobic metabolism and higher ethanol production. A mutant in the bifunctional acetaldehyde-CoA/alcohol dehydrogenase encoded by Imo1634 did not have altered antibiotic tolerance. However, a mutant...... in Imo1179 (eutE) encoding an aldehyde oxidoreductase where rerouting caused increased ethanol production was tolerant to three of four antibiotics tested. This shift in metabolism could be a survival strategy in response to antibiotics to avoid generation of ROS production from respiration by oxidation...

  19. Biogas energy production from tropical biomass wastes by anaerobic digestion

    Science.gov (United States)

    Anaerobic digestion (AD) is an attractive technology in tropical regions for converting locally abundant biomass wastes into biogas which can be used to produce heat, electricity, and transportation fuels. However, investigations on AD of tropical forestry wastes, such as albizia biomass, and food w...

  20. Mitochondria in Cancer Energy Metabolism

    OpenAIRE

    Kim, Aekyong

    2015-01-01

    Cancer is a disease characterized by uncontrolled growth. Metabolic demands to sustain rapid proliferation must be compelling since aerobic glycolysis is the first as well as the most commonly shared characteristic of cancer. During the last decade, the significance of metabolic reprogramming of cancer has been at the center of attention. Nonetheless, despite all the knowledge gained on cancer biology, the field is not able to reach agreement on the issue of mitochondria: Are damaged mitochon...

  1. Acidithiobacillus ferriphilus sp. nov., a facultatively anaerobic iron- and sulfur-metabolizing extreme acidophile.

    Science.gov (United States)

    Falagán, Carmen; Johnson, D Barrie

    2016-01-01

    The genus Acidithiobacillus includes three species that conserve energy from the oxidation of ferrous iron, as well as reduced sulfur, to support their growth. Previous work, based on multi-locus sequence analysis, identified a fourth group of iron- and sulfur-oxidizing acidithiobacilli as a potential distinct species. Eleven strains of 'Group IV' acidithiobacilli, isolated from different global locations, have been studied. These were all shown to be obligate chemolithotrophs, growing aerobically by coupling the oxidation of ferrous iron or reduced sulfur (but not hydrogen) to molecular oxygen, or anaerobically by the oxidation of reduced sulfur coupled to ferric iron reduction. All strains were mesophilic, although some were also psychrotolerant. Strain variation was also noted in terms of tolerance to extremely low pH and to elevated concentrations of transition metals. One strain was noted to display far greater tolerance to chloride than reported for other iron-oxidizing acidithiobacilli. All of the strains were able to catalyse the oxidative dissolution of pyrite and, on the basis of some of the combined traits of some of the strains examined, it is proposed that these may have niche roles in commercial mineral bioprocessing operations, such as for low temperature bioleaching of polysulfide ores in brackish waters. The name Acidithiobacillus ferriphilus sp. nov. is proposed to accommodate the strains described, with the type strain being M20T ( = DSM 100412T = JCM 30830T). PMID:26498321

  2. Metabolic Capabilities of Microorganisms Involved in and Associated with the Anaerobic Oxidation of Methane

    OpenAIRE

    Wegener, Gunter; Krukenberg, Viola; Ruff, S. Emil; Kellermann, Matthias Y.; Knittel, Katrin

    2016-01-01

    In marine sediments the anaerobic oxidation of methane with sulfate as electron acceptor (AOM) is responsible for the removal of a major part of the greenhouse gas methane. AOM is performed by consortia of anaerobic methane-oxidizing archaea (ANME) and their specific partner bacteria. The physiology of these organisms is poorly understood, which is due to their slow growth with doubling times in the order of months and the phylogenetic diversity in natural and in vitro AOM enrichments. Here w...

  3. Integration of an [FeFe]-hydrogenase into the anaerobic metabolism of Escherichia coli

    Science.gov (United States)

    Kelly, Ciarán L.; Pinske, Constanze; Murphy, Bonnie J.; Parkin, Alison; Armstrong, Fraser; Palmer, Tracy; Sargent, Frank

    2015-01-01

    Biohydrogen is a potentially useful product of microbial energy metabolism. One approach to engineering biohydrogen production in bacteria is the production of non-native hydrogenase activity in a host cell, for example Escherichia coli. In some microbes, hydrogenase enzymes are linked directly to central metabolism via diaphorase enzymes that utilise NAD+/NADH cofactors. In this work, it was hypothesised that heterologous production of an NAD+/NADH-linked hydrogenase could connect hydrogen production in an E. coli host directly to its central metabolism. To test this, a synthetic operon was designed and characterised encoding an apparently NADH-dependent, hydrogen-evolving [FeFe]-hydrogenase from Caldanaerobacter subterranus. The synthetic operon was stably integrated into the E. coli chromosome and shown to produce an active hydrogenase, however no H2 production was observed. Subsequently, it was found that heterologous co-production of a pyruvate::ferredoxin oxidoreductase and ferredoxin from Thermotoga maritima was found to be essential to drive H2 production by this system. This work provides genetic evidence that the Ca.subterranus [FeFe]-hydrogenase could be operating in vivo as an electron-confurcating enzyme. PMID:26839796

  4. Integration of an [FeFe]-hydrogenase into the anaerobic metabolism of Escherichia coli

    Directory of Open Access Journals (Sweden)

    Ciarán L. Kelly

    2015-12-01

    Full Text Available Biohydrogen is a potentially useful product of microbial energy metabolism. One approach to engineering biohydrogen production in bacteria is the production of non-native hydrogenase activity in a host cell, for example Escherichia coli. In some microbes, hydrogenase enzymes are linked directly to central metabolism via diaphorase enzymes that utilise NAD+/NADH cofactors. In this work, it was hypothesised that heterologous production of an NAD+/NADH-linked hydrogenase could connect hydrogen production in an E. coli host directly to its central metabolism. To test this, a synthetic operon was designed and characterised encoding an apparently NADH-dependent, hydrogen-evolving [FeFe]-hydrogenase from Caldanaerobacter subterranus. The synthetic operon was stably integrated into the E. coli chromosome and shown to produce an active hydrogenase, however no H2 production was observed. Subsequently, it was found that heterologous co-production of a pyruvate::ferredoxin oxidoreductase and ferredoxin from Thermotoga maritima was found to be essential to drive H2 production by this system. This work provides genetic evidence that the Ca.subterranus [FeFe]-hydrogenase could be operating in vivo as an electron-confurcating enzyme.

  5. Impact of salinity on the anaerobic metabolism of phosphate-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO).

    Science.gov (United States)

    Welles, L; Lopez-Vazquez, C M; Hooijmans, C M; van Loosdrecht, M C M; Brdjanovic, D

    2014-09-01

    The use of saline water as secondary quality water in urban environments for sanitation is a promising alternative towards mitigating fresh water scarcity. However, this alternative will increase the salinity in the wastewater generated that may affect the biological wastewater treatment processes, such as biological phosphorus removal. In addition to the production of saline wastewater by the direct use of saline water in urban environments, saline wastewater is also generated by some industries. Intrusion of saline water into the sewers is another source of salinity entering the wastewater treatment plant. In this study, the short-term effects of salinity on the anaerobic metabolism of phosphate-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO) were investigated to assess the impact of salinity on enhanced biological phosphorus removal. Hereto, PAO and GAO cultures enriched at a relatively low salinity level (0.02 % W/V) were exposed to salinity concentrations of up to 6 % (as NaCl) in anaerobic batch tests. It was demonstrated that both PAO and GAO are affected by higher salinity levels, with PAO being the more sensitive organisms to the increasing salinity. The maximum acetate uptake rate of PAO decreased by 71 % when the salinity increased from 0 to 1 %, while that of GAO decreased by 41 % for the same salinity increase. Regarding the stoichiometry of PAO, a decrease in the P-release/HAc uptake ratio accompanied with an increase in the glycogen consumption/HAc uptake ratio was observed for PAO when the salinity increased from 0 to 2 % salinity, indicating a metabolic shift from a poly-P-dependent to a glycogen-dependent metabolism. The anaerobic maintenance requirements of PAO and GAO increased as the salinity concentrations risen up to 4 % salinity. PMID:24831025

  6. Anaerobic biotechnological approaches for production of liquid energy carriers from biomass

    DEFF Research Database (Denmark)

    Karakashev, Dimitar Borisov; Thomsen, Anne Belinda; Angelidaki, Irini

    2007-01-01

    In recent years, increasing attention has been paid to the use of renewable biomass for energy production. Anaerobic biotechnological approaches for production of liquid energy carriers (ethanol and a mixture of acetone, butanol and ethanol) from biomass can be employed to decrease environmental...... pollution and reduce dependency on fossil fuels. There are two major biological processes that can convert biomass to liquid energy carriers via anaerobic biological breakdown of organic matter: ethanol fermentation and mixed acetone, butanol, ethanol (ABE) fermentation. The specific product formation...

  7. Cerebral energy metabolism during induced mitochondrial dysfunction

    DEFF Research Database (Denmark)

    Nielsen, T H; Bindslev, TT; Pedersen, S M;

    2013-01-01

    In patients with traumatic brain injury as well as stroke, impaired cerebral oxidative energy metabolism may be an important factor contributing to the ultimate degree of tissue damage. We hypothesize that mitochondrial dysfunction can be diagnosed bedside by comparing the simultaneous changes...... in brain tissue oxygen tension (PbtO(2)) and cerebral cytoplasmatic redox state. The study describes cerebral energy metabolism during mitochondrial dysfunction induced by sevoflurane in piglets....

  8. Effects of hyperammonemia on brain energy metabolism

    DEFF Research Database (Denmark)

    Schousboe, Arne; Waagepetersen, Helle S.; Leke, Renata;

    2014-01-01

    The literature related to the effects of elevated plasma ammonia levels on brain energy metabolism is abundant, but heterogeneous in terms of the conclusions. Thus, some studies claim that ammonia has a direct, inhibitory effect on energy metabolism whereas others find no such correlation...... but related to the fact that hepatic encephalopathy is always associated with reduced brain activity, a condition clearly characterized by a decreased CMRO2. Whether this may be related to changes in GABAergic function remains to be elucidated....

  9. The role of short-chain fatty acids in the interplay between diet, gut microbiota, and host energy metabolism

    NARCIS (Netherlands)

    Besten, G. den; Eunen, K. van; Groen, A.K.; Venema, K.; Reijngoud, D.J.; Bakker, B.M.

    2013-01-01

    Short-chain fatty acids (SCFAs), the end products of fermentation of dietary fibers by the anaerobic intestinal microbiota, have been shown to exert multiple beneficial effects on mammalian energy metabolism. The mechanisms underlying these effects are the subject of intensive research and encompass

  10. A Model of Solar Energy Utilisation in the Anaerobic Digestion of Cattle Manure

    NARCIS (Netherlands)

    Mashad, El H.; Loon, van W.K.P.; Zeeman, G.

    2003-01-01

    The anaerobic digestion of cow manure has a higher destruction of pathogens and weed seeds under thermophilic conditions compared to mesophilic conditions. To maintain such conditions, solar energy can be used. In this research, the consequences of the use of solar energy under Egyptian conditions a

  11. Toward homosuccinate fermentation: metabolic engineering of Corynebacterium glutamicum for anaerobic production of succinate from glucose and formate.

    Science.gov (United States)

    Litsanov, Boris; Brocker, Melanie; Bott, Michael

    2012-05-01

    Previous studies have demonstrated the capability of Corynebacterium glutamicum for anaerobic succinate production from glucose under nongrowing conditions. In this work, we have addressed two shortfalls of this process, the formation of significant amounts of by-products and the limitation of the yield by the redox balance. To eliminate acetate formation, a derivative of the type strain ATCC 13032 (strain BOL-1), which lacked all known pathways for acetate and lactate synthesis (Δcat Δpqo Δpta-ackA ΔldhA), was constructed. Chromosomal integration of the pyruvate carboxylase gene pyc(P458S) into BOL-1 resulted in strain BOL-2, which catalyzed fast succinate production from glucose with a yield of 1 mol/mol and showed only little acetate formation. In order to provide additional reducing equivalents derived from the cosubstrate formate, the fdh gene from Mycobacterium vaccae, coding for an NAD(+)-coupled formate dehydrogenase (FDH), was chromosomally integrated into BOL-2, leading to strain BOL-3. In an anaerobic batch process with strain BOL-3, a 20% higher succinate yield from glucose was obtained in the presence of formate. A temporary metabolic blockage of strain BOL-3 was prevented by plasmid-borne overexpression of the glyceraldehyde 3-phosphate dehydrogenase gene gapA. In an anaerobic fed-batch process with glucose and formate, strain BOL-3/pAN6-gap accumulated 1,134 mM succinate in 53 h with an average succinate production rate of 1.59 mmol per g cells (dry weight) (cdw) per h. The succinate yield of 1.67 mol/mol glucose is one of the highest currently described for anaerobic succinate producers and was accompanied by a very low level of by-products (0.10 mol/mol glucose).

  12. Metabolic potential of fatty acid oxidation and anaerobic respiration by abundant members of Thaumarchaeota and Thermoplasmata in deep anoxic peat

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Xueju [Georgia Inst. of Technology, Atlanta, GA (United States); Handley, Kim M. [Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States); Gilbert, Jack A. [Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States); Marine Biological Lab., Woods Hole, MA (United States); Zhejiang Univ., Hangzhou (China); Kostka, Joel E. [Georgia Inst. of Technology, Atlanta, GA (United States)

    2015-05-22

    To probe the metabolic potential of abundant Archaea in boreal peats, we reconstructed two near-complete archaeal genomes, affiliated with Thaumarchaeota group 1.1c (bin Fn1, 8% abundance), which was a genomically unrepresented group, and Thermoplasmata (bin Bg1, 26% abundance), from metagenomic data acquired from deep anoxic peat layers. Each of the near-complete genomes encodes the potential to degrade long-chain fatty acids (LCFA) via β-oxidation. Fn1 has the potential to oxidize LCFA either by syntrophic interaction with methanogens or by coupling oxidation with anaerobic respiration using fumarate as a terminal electron acceptor (TEA). Fn1 is the first Thaumarchaeota genome without an identifiable carbon fixation pathway, indicating that this mesophilic phylum encompasses more diverse metabolisms than previously thought. Furthermore, we report genetic evidence suggestive of sulfite and/or organosulfonate reduction by Thermoplasmata Bg1. In deep peat, inorganic TEAs are often depleted to extremely low levels, yet the anaerobic respiration predicted for two abundant archaeal members suggests organic electron acceptors such as fumarate and organosulfonate (enriched in humic substances) may be important for respiration and C mineralization in peatlands.

  13. Anaerobic digestion of organic solid waste for energy production

    OpenAIRE

    Nayono, Satoto Endar

    2010-01-01

    Anaerobic digestion of the organic fraction of municipal solid waste as such or together with food waste, press water or patatoes sludge was investigated to equilibrate methane production within a day or over the weekend, when no OFMSW was available. A stable co-digestion process could be achieved with COD degradation between 60 and 80 %. The max. organic loading rates were 28 kg COD/L,d. For stable methane production the OLR during Co-digestion should not excede 22,5 kg/L,d.

  14. Ecosustainable biomethane and fertilizerproduction through anaerobic co-digestionof animal manure and energy crops

    OpenAIRE

    Brizio, Enrico

    2012-01-01

    In Italy and many European countries energy production from biomass is encouraged by strong economic subsidies so that renewable energy plants, anaerobic digestion plant producing biogas in particular, are getting large diffusion. Nevertheless, it is necessary to define the environmental compatibility as well as technological and economic issues dealing with the emerging renewable energy scenario. This evaluation should take into account global parameters as well as environmental impacts at r...

  15. Mitochondrial Energy Metabolism and Thyroid Cancers.

    Science.gov (United States)

    Lee, Junguee; Chang, Joon Young; Kang, Yea Eun; Yi, Shinae; Lee, Min Hee; Joung, Kyong Hye; Kim, Kun Soon; Shong, Minho

    2015-06-01

    Primary thyroid cancers including papillary, follicular, poorly differentiated, and anaplastic carcinomas show substantial differences in biological and clinical behaviors. Even in the same pathological type, there is wide variability in the clinical course of disease progression. The molecular carcinogenesis of thyroid cancer has advanced tremendously in the last decade. However, specific inhibition of oncogenic pathways did not provide a significant survival benefit in advanced progressive thyroid cancer that is resistant to radioactive iodine therapy. Accumulating evidence clearly shows that cellular energy metabolism, which is controlled by oncogenes and other tumor-related factors, is a critical factor determining the clinical phenotypes of cancer. However, the role and nature of energy metabolism in thyroid cancer remain unclear. In this article, we discuss the role of cellular energy metabolism, particularly mitochondrial energy metabolism, in thyroid cancer. Determining the molecular nature of metabolic remodeling in thyroid cancer may provide new biomarkers and therapeutic targets that may be useful in the management of refractory thyroid cancers. PMID:26194071

  16. Simultaneous involvement of a tungsten-containing aldehyde:ferredoxin oxidoreductase and a phenylacetaldehyde dehydrogenase in anaerobic phenylalanine metabolism.

    Science.gov (United States)

    Debnar-Daumler, Carlotta; Seubert, Andreas; Schmitt, Georg; Heider, Johann

    2014-01-01

    Anaerobic phenylalanine metabolism in the denitrifying betaproteobacterium Aromatoleum aromaticum is initiated by conversion of phenylalanine to phenylacetate, which is further metabolized via benzoyl-coenzyme A (CoA). The formation of phenylacetate is catalyzed by phenylalanine transaminase, phenylpyruvate decarboxylase, and a phenylacetaldehyde-oxidizing enzyme. The presence of these enzymes was detected in extracts of cells grown with phenylalanine and nitrate. We found that two distinct enzymes are involved in the oxidation of phenylacetaldehyde to phenylacetate, an aldehyde:ferredoxin oxidoreductase (AOR) and a phenylacetaldehyde dehydrogenase (PDH). Based on sequence comparison, growth studies with various tungstate concentrations, and metal analysis of the enriched enzyme, AOR was shown to be a tungsten-containing enzyme, necessitating specific cofactor biosynthetic pathways for molybdenum- and tungsten-dependent enzymes simultaneously. We predict from the genome sequence that most enzymes of molybdopterin biosynthesis are shared, while the molybdate/tungstate uptake systems are duplicated and specialized paralogs of the sulfur-inserting MoaD and the metal-inserting MoeA proteins seem to be involved in dedicating biosynthesis toward molybdenum or tungsten cofactors. We also characterized PDH biochemically and identified both NAD(+) and NADP(+) as electron acceptors. We identified the gene coding for the enzyme and purified a recombinant Strep-tagged PDH variant. The homotetrameric enzyme is highly specific for phenylacetaldehyde, has cooperative kinetics toward the substrate, and shows considerable substrate inhibition. Our data suggest that A. aromaticum utilizes PDH as the primary enzyme during anaerobic phenylalanine degradation, whereas AOR is not essential for the metabolic pathway. We hypothesize a function as a detoxifying enzyme if high aldehyde concentrations accumulate in the cytoplasm, which would lead to substrate inhibition of PDH.

  17. Pyruvate Oxidoreductases Involved in Glycolytic Anaerobic Metabolism of Polychaetes from the Continental Shelf off Central-South Chile

    Science.gov (United States)

    González, R. R.; Quiñones, R. A.

    2000-10-01

    The presence of low oxygen conditions in extensive areas of the continental shelf off central-south Chile has important effects on the biochemical adaptations of the organisms living in this ecosystem. Polychaetes assemblages cohabit on the shelf with an extensively distributed prokaryotic community made up of giant filamentous sulfur bacteria (mainly Thioploca sp.). The aim of this research was to characterize the pyruvate oxidoreductases enzymes involved in the biochemical adaptation of these benthic polychaetes. Nine polychaete species ( Paraprionospio pinnata, Nephtys ferruginea, Glycera americana, Haploscoloplos sp., Lumbrineris composita, Sigambra bassi, Aricidea pigmentata , Cossura chilensis, and Pectinaria chilensis) were assayed for lactic dehydrogenase (LDH), octopine dehydrogenase (OPDH), strombine dehydrogenase (STRDH) and alanopine dehydrogenase (ALPDH). Each species had a characteristic number of the pyruvate oxidoreductases assayed ranging from 4 in Paraprionospio pinnata to 1 in Pectinaria chilensis . The pyruvate saturation curves obtained for the enzymes from all species analysed, except L. composita, suggest that NADH can be oxidized at different rates depending on the amino acid used in the reaction with pyruvate. Our results indicate that organisms having more that one pyruvate oxidoreductase present a greater metabolic capacity to cope with functional and environmental hypoxia because these enzymes would better regulate the pyruvate consumption rate during the transition period. Thus, the dominance of Paraprionospio pinnata in the study area and its worldwide distribution is consistent with its higher number of pyruvate oxidoreductases with different pyruvate consumption rates involved in anaerobic metabolism. Finally, a positive allometric relationship was found between body size and the specific activity of ALPDH, STRDH, and maximum pyruvate oxidoreductase specific activity. This latter result suggests a positive scaling of the specific

  18. Sodium signaling and astrocyte energy metabolism

    KAUST Repository

    Chatton, Jean-Yves

    2016-03-31

    The Na+ gradient across the plasma membrane is constantly exploited by astrocytes as a secondary energy source to regulate the intracellular and extracellular milieu, and discard waste products. One of the most prominent roles of astrocytes in the brain is the Na+-dependent clearance of glutamate released by neurons during synaptic transmission. The intracellular Na+ load collectively generated by these processes converges at the Na,K-ATPase pump, responsible for Na+ extrusion from the cell, which is achieved at the expense of cellular ATP. These processes represent pivotal mechanisms enabling astrocytes to increase the local availability of metabolic substrates in response to neuronal activity. This review presents basic principles linking the intracellular handling of Na+ following activity-related transmembrane fluxes in astrocytes and the energy metabolic pathways involved. We propose a role of Na+ as an energy currency and as a mediator of metabolic signals in the context of neuron-glia interactions. We further discuss the possible impact of the astrocytic syncytium for the distribution and coordination of the metabolic response, and the compartmentation of these processes in cellular microdomains and subcellular organelles. Finally, we illustrate future avenues of investigation into signaling mechanisms aimed at bridging the gap between Na+ and the metabolic machinery. © 2016 Wiley Periodicals, Inc.

  19. Sodium signaling and astrocyte energy metabolism.

    Science.gov (United States)

    Chatton, Jean-Yves; Magistretti, Pierre J; Barros, L Felipe

    2016-10-01

    The Na(+) gradient across the plasma membrane is constantly exploited by astrocytes as a secondary energy source to regulate the intracellular and extracellular milieu, and discard waste products. One of the most prominent roles of astrocytes in the brain is the Na(+) -dependent clearance of glutamate released by neurons during synaptic transmission. The intracellular Na(+) load collectively generated by these processes converges at the Na,K-ATPase pump, responsible for Na(+) extrusion from the cell, which is achieved at the expense of cellular ATP. These processes represent pivotal mechanisms enabling astrocytes to increase the local availability of metabolic substrates in response to neuronal activity. This review presents basic principles linking the intracellular handling of Na(+) following activity-related transmembrane fluxes in astrocytes and the energy metabolic pathways involved. We propose a role of Na(+) as an energy currency and as a mediator of metabolic signals in the context of neuron-glia interactions. We further discuss the possible impact of the astrocytic syncytium for the distribution and coordination of the metabolic response, and the compartmentation of these processes in cellular microdomains and subcellular organelles. Finally, we illustrate future avenues of investigation into signaling mechanisms aimed at bridging the gap between Na(+) and the metabolic machinery. GLIA 2016;64:1667-1676. PMID:27027636

  20. The intracellular to extracellular proton gradient following maximal whole body exercise and its implication for anaerobic energy production

    DEFF Research Database (Denmark)

    Voiantis, Stefanos; Secher, Niels H.; Quistorff, Bjørn

    2010-01-01

    intracellular acidosis and the decrease in PCr is that the anaerobic contribution to energy metabolism during maximal rowing corresponds to 4.47 ± 1.8 L O2, a value similar to that defined as the “accumulated oxygen deficit”. In conclusion, during maximal rowing the intracellular acidosis, expressed as proton......Maximal exercise elicits systemic acidosis where venous pH can drop to 6.74 and here we assessed how much lower the intracellular value (pHi) might be. The wrist flexor muscles are intensively involved in rowing and 31P-magnetic resonance spectroscopy allows for calculation of forearm pHi and...... concentration, surpasses ~4-fold the intravascular acidosis, while the resting gradient is ~2....

  1. Effects of Dietary Acid Load on Exercise Metabolism and Anaerobic Exercise Performance

    Directory of Open Access Journals (Sweden)

    Susan L. Caciano, Cynthia L. Inman, Elizabeth E. Gockel-Blessing, Edward P. Weiss

    2015-06-01

    Full Text Available Dietary acid load, quantified as the potential renal acid load (PRAL of the diet, affects systemic pH and acid-base regulation. In a previous cross-sectional study, we reported that a low dietary PRAL (i.e. alkaline promoting diet is associated with higher respiratory exchange ratio (RER values during maximal exercise. The purpose of the present study was to confirm the previous findings with a short-term dietary intervention study. Additionally, we sought to determine if changes in PRAL affects submaximal exercise RER (as a reflection of substrate utilization and anaerobic exercise performance. Subjects underwent a graded treadmill exercise test (GXT to exhaustion and an anaerobic exercise performance test on two occasions, once after following a low-PRAL diet and on a separate occasion, after a high-PRAL diet. The diets were continued as long as needed to achieve an alkaline or acid fasted morning urine pH, respectively, with all being 4-9 days in duration. RER was measured during the GXT with indirect calorimetry. The anaerobic performance test was a running time-to-exhaustion test lasting 1-4 min. Maximal exercise RER was lower in the low-PRAL trial compared to the high-PRAL trial (1.10 ± 0.02 vs. 1.20 ± 0.05, p = 0.037. The low-PRAL diet also resulted in a 21% greater time to exhaustion during anaerobic exercise (2.56 ± 0.36 vs. 2.11 ± 0.31 sec, p = 0.044 and a strong tendency for lower RER values during submaximal exercise at 70% VO2max (0.88 ± 0.02 vs. 0.96 ± 0.04, p = 0.060. Contrary to our expectations, a short-term low-PRAL (alkaline promoting diet resulted in lower RER values during maximal-intensity exercise. However, the low-PRAL diet also increased anaerobic exercise time to exhaustion and appears to have shifted submaximal exercise substrate utilization to favor lipid oxidation and spare carbohydrate, both of which would be considered favorable effects in the context of exercise performance.

  2. Regulation of energy metabolism during exercise

    NARCIS (Netherlands)

    Scheurink, AJW; Benthem, L; Steffens, AB; Zijlstra, WG

    1996-01-01

    This review deals with the peripheral sympathetic mechanisms involved in the regulation of energy substrate homeostasis during exercise. We have developed an experimental model for assessing sympathetic influences on metabolic processes in the awake and exercising rat. The data in this survey partic

  3. Energy metabolism of young, unadapted calves.

    NARCIS (Netherlands)

    Schrama, J.W.

    1993-01-01

    Calves reared for veal or other meat production are usually purchased before 2 weeks of age. The first weeks at the rearing unit represent a critical phase regarding their health. During this period calves are fed at a very low level. In this thesis, the energy metabolism of young, newly purchased c

  4. Metabolic and microbial community dynamics during the anaerobic digestion of maize silage in a two-phase process.

    Science.gov (United States)

    Sträuber, Heike; Lucas, Rico; Kleinsteuber, Sabine

    2016-01-01

    Two-phasic anaerobic digestion processes (hydrolysis/acidogenesis separated from acetogenesis/methanogenesis) can be used for biogas production on demand or a combined chemicals/bioenergy production. For an effective process control, detailed knowledge about the microbial catalysts and their correlation to process conditions is crucial. In this study, maize silage was digested in a two-phase process and interrelationships between process parameters and microbial communities were revealed. In the first-phase reactor, alternating metabolic periods were observed which emerged independently from the feeding frequency. During the L-period, up to 11.8 g L(-1) lactic acid was produced which significantly correlated to lactic acid bacteria of the genus Lactobacillus as the most abundant community members. During the alternating G-period, the production of volatile fatty acids (up to 5.3, 4.0 and 3.1 g L(-1) for propionic, n-butyric and n-caproic acid, respectively) dominated accompanied by a high gas production containing up to 28 % hydrogen. The relative abundance of various Clostridiales increased during this metabolic period. In the second-phase reactor, the metabolic fluctuations of the first phase were smoothed out resulting in a stable biogas production as well as stable bacterial and methanogenic communities. However, the biogas composition followed the metabolic dynamics of the first phase: the hydrogen content increased during the L-period whereas highest CH4/CO2 ratios (up to 2.8) were reached during the G-period. Aceticlastic Methanosaeta as well as hydrogenotrophic Methanoculleus and Methanobacteriaceae were identified as dominant methanogens. Consequently, a directed control of the first-phase stabilizing desired metabolic states can lead to an enhanced productivity regarding chemicals and bioenergy.

  5. Pareto optimality in organelle energy metabolism analysis.

    Science.gov (United States)

    Angione, Claudio; Carapezza, Giovanni; Costanza, Jole; Lió, Pietro; Nicosia, Giuseppe

    2013-01-01

    In low and high eukaryotes, energy is collected or transformed in compartments, the organelles. The rich variety of size, characteristics, and density of the organelles makes it difficult to build a general picture. In this paper, we make use of the Pareto-front analysis to investigate the optimization of energy metabolism in mitochondria and chloroplasts. Using the Pareto optimality principle, we compare models of organelle metabolism on the basis of single- and multiobjective optimization, approximation techniques (the Bayesian Automatic Relevance Determination), robustness, and pathway sensitivity analysis. Finally, we report the first analysis of the metabolic model for the hydrogenosome of Trichomonas vaginalis, which is found in several protozoan parasites. Our analysis has shown the importance of the Pareto optimality for such comparison and for insights into the evolution of the metabolism from cytoplasmic to organelle bound, involving a model order reduction. We report that Pareto fronts represent an asymptotic analysis useful to describe the metabolism of an organism aimed at maximizing concurrently two or more metabolite concentrations.

  6. Characterization of the periplasmic redox network that sustains the versatile anaerobic metabolism of Shewanella oneidensis MR-1

    Directory of Open Access Journals (Sweden)

    Mónica N. Alves

    2015-06-01

    Full Text Available The versatile anaerobic metabolism of the Gram-negative bacterium Shewanella oneidensis MR-1 (SOMR-1 relies on a multitude of redox proteins found in its periplasm. Most are multiheme cytochromes that carry electrons to terminal reductases of insoluble electron acceptors located at the cell surface, or bona fide terminal reductases of soluble electron acceptors. In this study, the interaction network of several multiheme cytochromes was explored by a combination of NMR spectroscopy, activity assays followed by UV-visible spectroscopy and comparison of surface electrostatic potentials. From these data the small tetraheme cytochrome (STC emerges as the main periplasmic redox shuttle in SOMR-1. It accepts electrons from CymA and distributes them to a number of terminal oxidoreductases involved in the respiration of various compounds. STC is also involved in the electron transfer pathway to reduce nitrite by interaction with the octaheme tetrathionate reductase (OTR, but not with cytochrome c nitrite reductase (ccNiR. In the main pathway leading the metal respiration STC pairs with flavocytochrome c (FccA, the other major periplasmic cytochrome, which provides redundancy in this important pathway. The data reveals that the two proteins compete for the binding site at the surface of MtrA, the decaheme cytochrome inserted on the periplasmic side of the MtrCAB-OmcA outer-membrane complex. However, this is not observed for the MtrA homologues. Indeed, neither STC nor FccA interact with MtrD, the best replacement for MtrA, and only STC is able to interact with the decaheme cytochrome DmsE of the outer-membrane complex DmsEFABGH. Overall, these results shown that STC plays a central role in the anaerobic respiratory metabolism of SOMR-1. Nonetheless, the trans-periplasmic electron transfer chain is functionally resilient as a consequence of redundancies that arise from the presence of alternative pathways that bypass/compete with STC.

  7. Recent development of anaerobic digestion processes for energy recovery from wastes.

    Science.gov (United States)

    Nishio, Naomichi; Nakashimada, Yutaka

    2007-02-01

    Anaerobic digestion leads to the overall gasification of organic wastewaters and wastes, and produces methane and carbon dioxide; this gasification contributes to reducing organic matter and recovering energy from organic carbons. Here, we propose three new processes and demonstrate the effectiveness of each process. By using complete anaerobic organic matter removal process (CARP), in which diluted wastewaters such as sewage and effluent from a methane fermentation digester were treated under anaerobic condition for post-treatment, the chemical oxygen demand (COD) in wastewater was decreased to less than 20 ppm. The dry ammonia-methane two-stage fermentation process (Am-Met process) is useful for the anaerobic treatment of nitrogen-rich wastes such as waste excess sludge, cow feces, chicken feces, and food waste without the dilution of the ammonia produced by water or carbon-rich wastes. The hydrogen-methane two-stage fermentation (Hy-Met process), in which the hydrogen produced in the first stage is used for a fuel cell system to generate electricity and the methane produced in the second stage is used to generate heat energy to heat the two reactors and satisfy heat requirements, is useful for the treatment of sugar-rich wastewaters, bread wastes, and biodiesel wastewaters. PMID:17368391

  8. Effects of dietary Acid load on exercise metabolism and anaerobic exercise performance.

    Science.gov (United States)

    Caciano, Susan L; Inman, Cynthia L; Gockel-Blessing, Elizabeth E; Weiss, Edward P

    2015-06-01

    Dietary acid load, quantified as the potential renal acid load (PRAL) of the diet, affects systemic pH and acid-base regulation. In a previous cross-sectional study, we reported that a low dietary PRAL (i.e. alkaline promoting diet) is associated with higher respiratory exchange ratio (RER) values during maximal exercise. The purpose of the present study was to confirm the previous findings with a short-term dietary intervention study. Additionally, we sought to determine if changes in PRAL affects submaximal exercise RER (as a reflection of substrate utilization) and anaerobic exercise performance. Subjects underwent a graded treadmill exercise test (GXT) to exhaustion and an anaerobic exercise performance test on two occasions, once after following a low-PRAL diet and on a separate occasion, after a high-PRAL diet. The diets were continued as long as needed to achieve an alkaline or acid fasted morning urine pH, respectively, with all being 4-9 days in duration. RER was measured during the GXT with indirect calorimetry. The anaerobic performance test was a running time-to-exhaustion test lasting 1-4 min. Maximal exercise RER was lower in the low-PRAL trial compared to the high-PRAL trial (1.10 ± 0.02 vs. 1.20 ± 0.05, p = 0.037). The low-PRAL diet also resulted in a 21% greater time to exhaustion during anaerobic exercise (2.56 ± 0.36 vs. 2.11 ± 0.31 sec, p = 0.044) and a strong tendency for lower RER values during submaximal exercise at 70% VO2max (0.88 ± 0.02 vs. 0.96 ± 0.04, p = 0.060). Contrary to our expectations, a short-term low-PRAL (alkaline promoting) diet resulted in lower RER values during maximal-intensity exercise. However, the low-PRAL diet also increased anaerobic exercise time to exhaustion and appears to have shifted submaximal exercise substrate utilization to favor lipid oxidation and spare carbohydrate, both of which would be considered favorable effects in the context of exercise performance. Key pointsShort-term (4-9 days) changes in

  9. Isolation, Growth, and Metabolism of an Obligately Anaerobic, Selenate-Respiring Bacterium, Strain SES-3

    OpenAIRE

    Oremland, Ronald S.; Blum, Jodi Switzer; Culbertson, Charles W.; Visscher, Pieter T.; Miller, Laurence G.; Dowdle, Phillip; Strohmaier, Frances E.

    1994-01-01

    A gram-negative, strictly anaerobic, motile vibrio was isolated from a selenate-respiring enrichment culture. The isolate, designated strain SES-3, grew by coupling the oxidation of lactate to acetate plus CO2 with the concomitant reduction of selenate to selenite or of nitrate to ammonium. No growth was observed on sulfate or selenite, but cell suspensions readily reduced selenite to elemental selenium (Se0). Hence, SES-3 can carry out a complete reduction of selenate to Se0. Washed cell sus...

  10. Anaerobic energy expenditure and mechanical efficiency during exhaustive leg press exercise

    DEFF Research Database (Denmark)

    Gorostiaga, Esteban M.; Navarro-Amézqueta, Ion; Cusso, Roser;

    2010-01-01

    average duration of exercise (18.4 ± 4.0 vs 14.2 ± 2.1 s). These data indicate that during a set of 10RM of bilateral leg press exercise there is a decrease in power output which is associated with a decrease in the contribution of PCr and/or an increase in muscle lactate. The higher energy cost per......Information about anaerobic energy production and mechanical efficiency that occurs over time during short-lasting maximal exercise is scarce and controversial. Bilateral leg press is an interesting muscle contraction model to estimate anaerobic energy production and mechanical efficiency during...... maximal exercise because it largely differs from the models used until now. This study examined the changes in muscle metabolite concentration and power output production during the first and the second half of a set of 10 repetitions to failure (10RM) of bilateral leg press exercise. On two separate days...

  11. Improved Energy Recovery by Anaerobic Grey Water Sludge Treatment with Black Water

    Directory of Open Access Journals (Sweden)

    Taina Tervahauta

    2014-08-01

    Full Text Available This study presents the potential of combining anaerobic grey water sludge treatment with black water in an up-flow anaerobic sludge blanket (UASB reactor to improve energy recovery within source-separated sanitation concepts. Black water and the mixture of black water and grey water sludge were compared in terms of biochemical methane potential (BMP, UASB reactor performance, chemical oxygen demand (COD mass balance and methanization. Grey water sludge treatment with black water increased the energy recovery by 23% in the UASB reactor compared to black water treatment. The increase in the energy recovery can cover the increased heat demand of the UASB reactor and the electricity demand of the grey water bioflocculation system with a surplus of 0.7 kWh/cap/y electricity and 14 MJ/cap/y heat. However, grey water sludge introduced more heavy metals in the excess sludge of the UASB reactor and might therefore hinder its soil application.

  12. Research on Anaerobic Digestion: Optimization and Scalability of Mixed High-strength Food Processing Wastes for Renewable Biogas Energy

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhongtang [The Ohio State Univ., Columbus, OH (United States); Hitzhusen, Fredrick [The Ohio State Univ., Columbus, OH (United States)

    2012-12-27

    This research project developed and improved anaerobic digestion technologies, created a comprehensive Inventory of Ohio Biomass and a database of microorganisms of anaerobic digesters, and advanced knowledge and understanding of the underpinning microbiology of the anaerobic digestion process. The results and finding of this research project may be useful for future development and implementation of anaerobic digesters, especially at livestock farms. Policy makers and investors may also find the information on the biomass availability in Ohio and valuation of energy projects useful in policy making and making of investment decisions. The public may benefit from the information on biogas as an energy source and the potential impact of anaerobic digester projects on their neighborhoods.

  13. Effect of creatine on aerobic and anaerobic metabolism in skeletal muscle in swimmers.

    OpenAIRE

    Thompson, C. H.; Kemp, G J; Sanderson, A. L.; Dixon, R M; Styles, P; Taylor, D J; Radda, G K

    1996-01-01

    OBJECTIVE: To examine the effect of a relatively low dose of creatine on skeletal muscle metabolism and oxygen supply in a group of training athletes. METHODS: 31P magnetic resonance and near-infrared spectroscopy were used to study calf muscle metabolism in a group of 10 female members of a university swimming team. Studies were performed before and after a six week period of training during which they took either 2 g creatine daily or placebo. Calf muscle metabolism and creatine/choline rat...

  14. ANAEROBIC TRANSFORMATION OF BIODEGRADABLE WASTE; SIMULTANEOUS PRODUCTION OF ENERGY AND FERTILIZER

    Directory of Open Access Journals (Sweden)

    Amirhossein Malakahmad

    2013-01-01

    Full Text Available Almost 40% of the total waste produced in developing countries is made of biodegradable waste. Typically the waste including the biodegradable portion is transported to the so-called landfills without any segregation process, treatment and utilization in advance. Although mitigation practices such as source reduction, reuse and recycle are essential and required to be practiced in any integrated waste management plan, one of the best approaches to reduce the volume of the waste goes to the landfills is biological transformation. Biological transformation of waste occurs in two major categories; aerobic and anaerobic biodegradation. Anaerobic transformation of biodegradable waste produces methane gas (CH4 which is the valuable source of energy. At first the gas has some impurities such as CO2 and other trace materials which are required to be removed from the main stream before utilization. In addition to methane, the byproduct of the anaerobic process is slurry that can be used as soil amendment agent. It contains several vital elements such as nitrogen, phosphorous and potassium (N, P and K for crops. The quality of slurry is required to be assessed since it affects the soil conditions and plants growth. In this study the importance of biological transformation in waste management systems has been discussed. Different methods and significant factors in methane production via anaerobic digestion have been highlighted and finally, the criteria of produced fertilizer have been elaborated.

  15. Significance of anaerobic digestion as a source of clean energy in wastewater treatment plants

    International Nuclear Information System (INIS)

    Highlights: • Between 39% and 79% of WWTP energy requirements could be fulfilled by the biogas produced. • Payback period of a biogas CHP engine is <2 years if energy price is ⩾216 € kJ−1. • 34% of the wastewater energy content is recovered into biogas. • Elemental composition is a good tool to estimate energy content of WWTP streams. - Abstract: Nowadays, energy consumption is one of the major concerns of wastewater treatment plants (WWTPs). Time ago, anaerobic digestion was usually implemented for sewage sludge stabilization but energy recovery optimization has recently gained importance. The energy balance of five WWTPs located in Catalonia revealed that depending on the configuration of the plant and its operation, between 39% and 76% of the total electric energy consumed in the WWTP could be supplied by the biogas produced. In the second part of this work, a carbon, nitrogen and sulphur flux analysis was carried out, together with an energy content evaluation for each stream in the WWTP. Results showed that 37% of the carbon found in the raw wastewater was removed during the active sludge process and 24% was transformed into biogas. The remaining carbon was found in the anaerobic dewatered sludge (22%) and in the treated water (19%). As a result, 34% of the initial energy was recovered in the form of biogas

  16. Solar Thermophilic Anaerobic Reactor (STAR) for Renewable Energy Production

    OpenAIRE

    Mashad, El, H.

    2003-01-01

    Liquid and solid cattle manures are major waste streams inEgypt. The main objective of this research was maximising the net energy production from these wastes by using a solar energy heating system. High concentration of ammonia can strongly affect the gross methane production via inhibition of methanogenesis and reduced hydrolysis. The latter is only limited addressed so far in literature and therefore taken as a second objective of this study.To be able to design a solar thermophilic anaer...

  17. Methane production through anaerobic digestion of dedicated energy crops

    OpenAIRE

    Di Girolamo, Giuseppe

    2014-01-01

    Methane yield of ligno-cellulosic substrates (i.e. dedicated energy crops and agricultural residues) may be limited by their composition and structural features. Hence, biomass pre-treatments are envisaged to overcome this constraint. This thesis aimed at: i) assessing biomass and methane yield of dedicated energy crops; ii) evaluating the effects of hydrothermal pre-treatments on methane yield of Arundo; iii) investigating the effects of NaOH pre-treatments and iv) acid pre-treatments on che...

  18. Metabolic capabilities of microorganisms involved in and associated with the anaerobic oxidation of methane

    Directory of Open Access Journals (Sweden)

    Gunter eWegener

    2016-02-01

    Full Text Available In marine sediments the anaerobic oxidation of methane with sulfate as electron acceptor (AOM is responsible for the removal of a major part of the greenhouse gas methane. AOM is performed by consortia of anaerobic methane-oxidizing archaea (ANME and their specific partner bacteria. The physiology of these organisms is poorly understood, which is due to their slow growth with doubling times in the order of months and the phylogenetic diversity in natural and in vitro AOM enrichments. Here we study sediment-free long-term AOM enrichments that were cultivated from seep sediments sampled off the Italian Island Elba (20°C; hereon called E20 and from hot vents of the Guaymas Basin, Gulf of California, cultivated at 37°C (G37 or at 50°C (G50. These enrichments were dominated by consortia of ANME-2 archaea and Seep-SRB2 partner bacteria (E20 or by ANME-1, forming consortia with Seep-SRB2 bacteria (G37 or with bacteria of the HotSeep-1 cluster (G50. We investigate lipid membrane compositions as possible factors for the different temperature affinities of the different ANME clades and show autotrophy as characteristic feature for both ANME clades and their partner bacteria. Although in the absence of additional substrates methane formation was not observed, methanogenesis from methylated substrates (methanol and methylamine could be quickly stimulated in the E20 and the G37 enrichment. Responsible for methanogenesis are archaea from the genus Methanohalophilus and Methanococcoides, which are minor community members during AOM (1 to 7‰ of archaeal 16S rRNA gene amplicons. In the same two cultures also sulfur disproportionation could be quickly stimulated by addition of zero-valent colloidal sulfur. The isolated partner bacteria are likewise minor community members (1 to 9‰ of bacterial 16S rRNA gene amplicons, whereas the dominant partner bacteria (Seep-SRB1a, Seep-SRB2 or HotSeep-1 did not grow on elemental sulfur. Our results support a

  19. Metabolic Capabilities of Microorganisms Involved in and Associated with the Anaerobic Oxidation of Methane.

    Science.gov (United States)

    Wegener, Gunter; Krukenberg, Viola; Ruff, S Emil; Kellermann, Matthias Y; Knittel, Katrin

    2016-01-01

    In marine sediments the anaerobic oxidation of methane with sulfate as electron acceptor (AOM) is responsible for the removal of a major part of the greenhouse gas methane. AOM is performed by consortia of anaerobic methane-oxidizing archaea (ANME) and their specific partner bacteria. The physiology of these organisms is poorly understood, which is due to their slow growth with doubling times in the order of months and the phylogenetic diversity in natural and in vitro AOM enrichments. Here we study sediment-free long-term AOM enrichments that were cultivated from seep sediments sampled off the Italian Island Elba (20°C; hereon called E20) and from hot vents of the Guaymas Basin, Gulf of California, cultivated at 37°C (G37) or at 50°C (G50). These enrichments were dominated by consortia of ANME-2 archaea and Seep-SRB2 partner bacteria (E20) or by ANME-1, forming consortia with Seep-SRB2 bacteria (G37) or with bacteria of the HotSeep-1 cluster (G50). We investigate lipid membrane compositions as possible factors for the different temperature affinities of the different ANME clades and show autotrophy as characteristic feature for both ANME clades and their partner bacteria. Although in the absence of additional substrates methane formation was not observed, methanogenesis from methylated substrates (methanol and methylamine) could be quickly stimulated in the E20 and the G37 enrichment. Responsible for methanogenesis are archaea from the genus Methanohalophilus and Methanococcoides, which are minor community members during AOM (1-7‰ of archaeal 16S rRNA gene amplicons). In the same two cultures also sulfur disproportionation could be quickly stimulated by addition of zero-valent colloidal sulfur. The isolated partner bacteria are likewise minor community members (1-9‰ of bacterial 16S rRNA gene amplicons), whereas the dominant partner bacteria (Seep-SRB1a, Seep-SRB2, or HotSeep-1) did not grow on elemental sulfur. Our results support a functioning of AOM as

  20. Characterization of a corrinoid protein involved in the C1 metabolism of strict anaerobic bacterium Moorella thermoacetica.

    Science.gov (United States)

    Das, Amaresh; Fu, Zheng-Qing; Tempel, Wolfram; Liu, Zhi-Jie; Chang, Jessie; Chen, Lirong; Lee, Doowon; Zhou, Weihong; Xu, Hao; Shaw, Neil; Rose, John P; Ljungdahl, Lars G; Wang, Bi-Cheng

    2007-04-01

    The strict anaerobic, thermophilic bacterium Moorella thermoacetica metabolizes C1 compounds for example CO(2)/H(2), CO, formate, and methanol into acetate via the Wood/Ljungdahl pathway. Some of the key steps in this pathway include the metabolism of the C1 compounds into the methyl group of methylenetetrahydrofolate (MTHF) and the transfer of the methyl group from MTHF to the methyl group of acetyl-CoA catalyzed by methyltransferase, corrinoid protein and CO dehydrogenase/acetyl CoA synthase. Recently, we reported the crystallization of a 25 kDa methanol-induced corrinoid protein from M. thermoacetica (Zhou et al., Acta Crystallogr F 2005; 61:537-540). In this study we analyzed the crystal structure of the 25 kDa protein and provide genetic and biochemical evidences supporting its role in the methanol metabolism of M. thermoacetia. The 25 kDa protein was encoded by orf1948 of contig 303 in the M. thermoacetica genome. It resembles similarity to MtaC the corrinoid protein of the methanol:CoM methyltransferase system of methane producing archaea. The latter enzyme system also contains two additional enzymes MtaA and MtaB. Homologs of MtaA and MtaB were found to be encoded by orf2632 of contig 303 and orf1949 of contig 309, respectively, in the M. thermoacetica genome. The orf1948 and orf1949 were co-transcribed from a single polycistronic operon. Metal analysis and spectroscopic data confirmed the presence of cobalt and the corrinoid in the purified 25 kDa protein. High resolution X-ray crystal structure of the purified 25 kDa protein revealed corrinoid as methylcobalamin with the imidazole of histidine as the alpha-axial ligand replacing benziimidazole, suggesting base-off configuration for the corrinoid. Methanol significantly activated the expression of the 25 kDa protein. Cyanide and nitrate inhibited methanol metabolism and suppressed the level of the 25 kDa protein. The results suggest a role of the 25 kDa protein in the methanol metabolism of M

  1. Biogas generation potential by anaerobic digestion for sustainable energy development in India

    Energy Technology Data Exchange (ETDEWEB)

    Rao, P. Venkateswara; Baral, Saroj S.; Dey, Ranjan [Chemical Engineering Group, Birla Institute of Technology and Science, Goa Campus, Zuari Nagar, Goa 403726 (India); Mutnuri, Srikanth [Biology Group, Birla Institute of Technology and Science, Goa Campus, Zuari Nagar, Goa 403726 (India)

    2010-09-15

    The potential of biogas generation from anaerobic digestion of different waste biomass in India has been studied. Renewable energy from biomass is one of the most efficient and effective options among the various other alternative sources of energy currently available. The anaerobic digestion of biomass requires less capital investment and per unit production cost as compared to other renewable energy sources such as hydro, solar and wind. Further, renewable energy from biomass is available as a domestic resource in the rural areas, which is not subject to world price fluctuations or the supply uncertainties as of imported and conventional fuels. In India, energy demand from various sectors is increased substantially and the energy supply is not in pace with the demand which resulted in a deficit of 11,436 MW which is equivalent to 12.6% of peak demand in 2006. The total installed capacity of bioenergy generation till 2007 from solid biomass and waste to energy is about 1227 MW against a potential of 25,700 MW. The bioenergy potential from municipal solid waste, crop residue and agricultural waste, wastewater sludge, animal manure, industrial waste which includes distilleries, dairy plants, pulp and paper, poultry, slaughter houses, sugar industries is estimated. The total potential of biogas from all the above sources excluding wastewater has been estimated to be 40,734 Mm{sup 3}/year. (author)

  2. Potential enhancement of direct interspecies electron transfer for syntrophic metabolism of propionate and butyrate with biochar in up-flow anaerobic sludge blanket reactors.

    Science.gov (United States)

    Zhao, Zhiqiang; Zhang, Yaobin; Holmes, Dawn E; Dang, Yan; Woodard, Trevor L; Nevin, Kelly P; Lovley, Derek R

    2016-06-01

    Promoting direct interspecies electron transfer (DIET) to enhance syntrophic metabolism may be a strategy for accelerating the conversion of organic wastes to methane, but microorganisms capable of metabolizing propionate and butyrate via DIET under methanogenic conditions have yet to be identified. In an attempt to establish methanogenic communities metabolizing propionate or butyrate with DIET, enrichments were initiated with up-flow anaerobic sludge blanket (UASB), similar to those that were previously reported to support communities that metabolized ethanol with DIET that relied on direct biological electrical connections. In the absence of any amendments, microbial communities enriched were dominated by microorganisms closely related to pure cultures that are known to metabolize propionate or butyrate to acetate with production of H2. When biochar was added to the reactors there was a substantial enrichment on the biochar surface of 16S rRNA gene sequences closely related to Geobacter and Methanosaeta species known to participate in DIET. PMID:26967338

  3. Circulating follistatin in relation to energy metabolism.

    Science.gov (United States)

    Hansen, Jakob Schiøler; Plomgaard, Peter

    2016-09-15

    Recently, substantial evidence has emerged that the liver contributes significantly to the circulating levels of follistatin and that circulating follistatin is tightly regulated by the glucagon-to-insulin ratio. Both observations are based on investigations of healthy subjects. These novel findings challenge the present view of circulating follistatin in human physiology, being that circulating follistatin is a result of spill-over from para/autocrine actions in various tissues and cells. Follistatin as a liver-derived protein under the regulation of glucagon-to-insulin ratio suggests a relation to energy metabolism. In this narrative review, we attempt to reconcile the existing findings on circulating follistatin with the novel concept that circulating follistatin is a liver-derived molecule regulated by the glucagon-to-insulin ratio. The picture emerging is that conditions associated with elevated levels of circulating follistatin have a metabolic denominator with decreased insulin sensitivity and/or hyperglucagoneimia. PMID:27264073

  4. Effects of temperature and extracellular pH on metabolites: kinetics of anaerobic metabolism in resting muscle by 31P- and 1H-NMR spectroscopy.

    Science.gov (United States)

    Vezzoli, Alessandra; Gussoni, Maristella; Greco, Fulvia; Zetta, Lucia

    2003-09-01

    Environmental stress, such as low temperature, extracellular acidosis and anoxia, is known to play a key role in metabolic regulation. The aim of the present study was to gain insight into the combined temperature-pH regulation of metabolic rate in frog muscle, i.e. an anoxia-tolerant tissue. The rate of exergonic metabolic processes occurring in resting isolated muscles was determined at 15 degrees C and 25 degrees C as well as at extracellular pH values higher (7.9), similar (7.3) and lower (7.0) than the physiological intracellular pH. (31)P and (1)H nuclear magnetic resonance spectroscopy high-resolution measurements were carried out at 4.7 T in isolated frog (Rana esculenta) gastrocnemius muscle during anoxia to assess, by means of reference compounds, the concentration of all phosphate metabolites and lactate. Intra- and extracellular pH was also determined. In the range of examined temperatures (15-25 degrees C), the temperature dependence of anaerobic glycolysis was found to be higher than that of PCr depletion (Q(10)=2.3). High-energy phosphate metabolism was confirmed to be the initial and preferential energy source. The rate of phosphocreatine hydrolysis did not appear to be affected by extracellular pH changes. By contrast, independent of the intracellular pH value, at the higher temperature (25 degrees C) a lowering of the extracellular pH from 7.9 to 7.0 caused a depression in lactate accumulation. This mechanism was ascribed to the transmembrane proton concentration gradient. This parameter was demonstrated to regulate glycolysis, probably through a reduced lactate efflux, depending on the activity of the lactate-H(+) co-transporter. The calculated intracellular buffer capacity was related to intra- and extracellular pH and temperature. At the experimental extracellular pH of 7.9 and at a temperature of 15 degrees C and 25 degrees C, calculated intracellular buffering capacity was 29.50 micromol g(-1) pH unit(-1) and 69.98 micromol g(-1) pH unit(-1

  5. Anaerobic Induction of Isocitrate Lyase and Malate Synthase in Submerged Rice Seedlings Indicates the Important Metabolic Role of the Glyoxylate Cycle

    Institute of Scientific and Technical Information of China (English)

    Ying LU; Yong-Rui WU; Bin HAN

    2005-01-01

    The glyoxylate cycle is a modified form of the tricarboxylic acid cycle that converts C2compounds into C4 dicarboxylic acids at plant developmental stages. By studying submerged rice seedlings,we revealed the activation of the glyoxylate cycle by identifying the increased transcripts of mRNAs of the genes of isocitrate lyase (ICL) and malate synthase (MS), two characteristic enzymes of the glyoxylate cycle. Northern blot analysis showed that ICL and MS were activated in the prolonged anaerobic environment.The activity assay of pyruvate decarboxylase and ICL in the submerged seedlings indicated an 8.8-fold and 3.5-fold increase over that in the unsubmerged seedlings, respectively. The activity assay of acetyl-coenzyme A synthetase in the submerged seedlings indicated a 3-fold increase over that in the unsubmerged seedlings, which is important for initiating acetate metabolism. Consequently, we concluded that the glyoxylate cycle was involved in acetate metabolism under anaerobic conditions.

  6. Glycolysis in energy metabolism during seizures

    Institute of Scientific and Technical Information of China (English)

    Heng Yang; Jiongxing Wu; Ren Guo; Yufen Peng; Wen Zheng; Ding Liu; Zhi Song

    2013-01-01

    Studies have shown that glycolysis increases during seizures, and that the glycolytic metabolite lactic acid can be used as an energy source. However, how lactic acid provides energy for seizures and how it can participate in the termination of seizures remains unclear. We reviewed possible mechanisms of glycolysis involved in seizure onset. Results showed that lactic acid was involved in seizure onset and provided energy at early stages. As seizures progress, lactic acid reduces the pH of tissue and induces metabolic acidosis, which terminates the seizure. The specific mechanism of lactic acid-induced acidosis involves several aspects, which include lactic acid-induced inhibition of the glycolytic enzyme 6-diphosphate kinase-1, inhibition of the N-methyl-D-aspartate receptor, activation of the acid-sensitive 1A ion channel, strengthening of the receptive mechanism of the inhibitory neurotransmitter γ-aminobutyric acid, and changes in the intra- and extracellular environment.

  7. Isolation, growth, and metabolism of an obligately anaerobic, selenate- respiring bacterium, strain SES-3

    Science.gov (United States)

    Oremland, R.S.; Blum, J.S.; Culbertson, C.W.; Visscher, P.T.; Miller, L.G.; Dowdle, P.; Strohmaier, F.E.

    1994-01-01

    A gram-negative, strictly anaerobic, motile vibrio was isolated from a selenate-respiring enrichment culture. The isolate, designated strain SES-3, grew by coupling the oxidation of lactate to acetate plus CO2 with the concomitant reduction of selenate to selenite or of nitrate to ammonium. No growth was observed on sulfate or selenite, but cell suspensions readily reduced selenite to elemental selenium (Se0). Hence, SES-3 can carry out a complete reduction of selenate to Se0. Washed cell suspensions of selenate- grown cells did not reduce nitrate, and nitrate-grown cells did not reduce selenate, indicating that these reductions are achieved by separate inducible enzyme systems. However, both nitrate-grown and selenate-grown cells have a constitutive ability to reduce selenite or nitrite. The oxidation of [14C]lactate to 14CO2 coupled to the reduction of selenate or nitrate by cell suspensions was inhibited by CCCP (carbonyl cyanide m- chlorophenylhydrazone), cyanide, and azide. High concentrations of selenite (5 mM) were readily reduced to Se0 by selenate-grown cells, but selenite appeared to block the synthesis of pyruvate dehydrogenase. Tracer experiments with [75Se]selenite indicated that cell suspensions could achieve a rapid and quantitative reduction of selenite to Se0. This reduction was totally inhibited by sulfite, partially inhibited by selenate or nitrite, but unaffected by sulfate or nitrate. Cell suspensions could reduce thiosulfate, but not sulfite, to sulfide. These results suggest that reduction of selenite to Se0 may proceed, in part, by some of the components of a dissimilatory system for sulfur oxyanions.

  8. Bioenergy from stillage anaerobic digestion to enhance the energy balance ratio of ethanol production.

    Science.gov (United States)

    Fuess, Lucas Tadeu; Garcia, Marcelo Loureiro

    2015-10-01

    The challenges associated with the availability of fossil fuels in the past decades intensified the search for alternative energy sources, based on an ever-increasing demand for energy. In this context, the application of anaerobic digestion (AD) as a core treatment technology in industrial plants should be highlighted, since this process combines the pollution control of wastewaters and the generation of bioenergy, based on the conversion of the organic fraction to biogas, a methane-rich gaseous mixture that may supply the energetic demands in industrial plants. In this context, this work aimed at assessing the energetic potential of AD applied to the treatment of stillage, the main wastewater from ethanol production, in an attempt to highlight the improvements in the energy balance ratio of ethanol by inserting the heating value of methane as a bioenergy source. At least 5-15% of the global energy consumption in the ethanol industry could be supplied by the energetic potential of stillage, regardless the feedstock (i.e. sugarcane, corn or cassava). The association between bagasse combustion and stillage anaerobic digestion in sugarcane-based distilleries could provide a bioenergy surplus of at least 130% of the total fossil fuel input into the ethanol plant, considering only the energy from methane. In terms of financial aspects, the economic gains could reach US$ 0.1901 and US$ 0.0512 per liter of produced ethanol, respectively for molasses- (Brazil) and corn-based (EUA) production chains. For large-scale (∼1000 m(3)EtOH per day) Brazilian molasses-based plants, an annual economic gain of up to US$ 70 million could be observed. Considering the association between anaerobic and aerobic digestion, for the scenarios analyzed, at least 25% of the energetic potential of stillage would be required to supply the energy consumption with aeration, however, more suitable effluents for agricultural application could be produced. The main conclusion from this work

  9. Bioenergy from stillage anaerobic digestion to enhance the energy balance ratio of ethanol production.

    Science.gov (United States)

    Fuess, Lucas Tadeu; Garcia, Marcelo Loureiro

    2015-10-01

    The challenges associated with the availability of fossil fuels in the past decades intensified the search for alternative energy sources, based on an ever-increasing demand for energy. In this context, the application of anaerobic digestion (AD) as a core treatment technology in industrial plants should be highlighted, since this process combines the pollution control of wastewaters and the generation of bioenergy, based on the conversion of the organic fraction to biogas, a methane-rich gaseous mixture that may supply the energetic demands in industrial plants. In this context, this work aimed at assessing the energetic potential of AD applied to the treatment of stillage, the main wastewater from ethanol production, in an attempt to highlight the improvements in the energy balance ratio of ethanol by inserting the heating value of methane as a bioenergy source. At least 5-15% of the global energy consumption in the ethanol industry could be supplied by the energetic potential of stillage, regardless the feedstock (i.e. sugarcane, corn or cassava). The association between bagasse combustion and stillage anaerobic digestion in sugarcane-based distilleries could provide a bioenergy surplus of at least 130% of the total fossil fuel input into the ethanol plant, considering only the energy from methane. In terms of financial aspects, the economic gains could reach US$ 0.1901 and US$ 0.0512 per liter of produced ethanol, respectively for molasses- (Brazil) and corn-based (EUA) production chains. For large-scale (∼1000 m(3)EtOH per day) Brazilian molasses-based plants, an annual economic gain of up to US$ 70 million could be observed. Considering the association between anaerobic and aerobic digestion, for the scenarios analyzed, at least 25% of the energetic potential of stillage would be required to supply the energy consumption with aeration, however, more suitable effluents for agricultural application could be produced. The main conclusion from this work

  10. Mitochondrial uncoupling proteins and energy metabolism

    Directory of Open Access Journals (Sweden)

    Rosa Anna Busiello

    2015-02-01

    Full Text Available Understanding the metabolic factors that contribute to energy metabolism (EM is critical for the development of new treatments for obesity and related diseases. Mitochondrial oxidative phosphorylation is not perfectly coupled to ATP synthesis, and the process of proton-leak plays a crucial role. Proton-leak accounts for a significant part of the resting metabolic rate and therefore enhancement of this process represents a potential target for obesity treatment. Since their discovery, uncoupling proteins have stimulated great interest due to their involvement in mitochondrial-inducible proton-leak. Despite the widely accepted uncoupling/thermogenic effect of uncoupling protein one (UCP1, which was the first in this family to be discovered, the reactions catalyzed by its homologue UCP3 and the physiological role remain under debate.This review provides an overview of the role played by UCP1 and UCP3 in mitochondrial uncoupling/functionality as well as EM and suggests that they are a potential therapeutic target for treating obesity and its related diseases such as type II diabetes mellitus.

  11. A new concept for enhancing energy recovery from agricultural residues by coupling anaerobic digestion and pyrolysis process

    OpenAIRE

    Monlau, Florian; Sambusiti, Cécilia; Antoniou, N; Barakat, Abdellatif; Zabaniotou, A.

    2015-01-01

    In a full-scale anaerobic digestion plant, agricultural residues are generally converted into biogas and digestate, the latter usually produced in large amount. Generally, biogas is converted into heat, often lost, and electricity, which is completely valorized or it is sold to the public grid. In this context, the aim of this study was to investigate the feasibility to combine anaerobic digestion and pyrolysis processes in order to increase the energy recovery from agricultural residues and ...

  12. Analysis of the metatranscriptome of microbial communities of an alkaline hot sulfur spring revealed different gene encoding pathway enzymes associated with energy metabolism.

    Science.gov (United States)

    Tripathy, Swetaleena; Padhi, Soumesh Kumar; Mohanty, Sriprakash; Samanta, Mrinal; Maiti, Nikhil Kumar

    2016-07-01

    Alkaline sulfur hot springs notable for their specialized and complex ecosystem powered by geothermal energy are abundantly rich in different chemotrophic and phototrophic thermophilic microorganisms. Survival and adaptation of these organisms in the extreme environment is specifically related to energy metabolism. To gain a better understanding of survival mechanism of the organisms in these ecosystems, we determined the different gene encoding enzymes associated with anaerobic pathways of energy metabolism by applying the metatranscriptomics approach. The analysis of the microbial population of hot sulfur spring revealed the presence of both aerobic and anaerobic organisms indicating dual mode of lifestyle of the community members. Proteobacteria (28.1 %) was the most dominant community. A total of 988 reads were associated with energy metabolism, out of which 33.7 % of the reads were assigned to nitrogen, sulfur, and methane metabolism based on KEGG classification. The major lineages of hot spring communities were linked with the anaerobic pathways. Different gene encoding enzymes (hao, nir, nar, cysH, cysI, acs) showed the involvement of microbial members in nitrification, denitrification, dissimilatory sulfate reduction, and methane generation. This study enhances our understanding of important gene encoding enzymes involved in energy metabolism, required for the survival and adaptation of microbial communities in the hot spring.

  13. Microbial anaerobic digestion (bio-digesters) as an approach to the decontamination of animal wastes in pollution control and the generation of renewable energy.

    Science.gov (United States)

    Manyi-Loh, Christy E; Mamphweli, Sampson N; Meyer, Edson L; Okoh, Anthony I; Makaka, Golden; Simon, Michael

    2013-09-01

    With an ever increasing population rate; a vast array of biomass wastes rich in organic and inorganic nutrients as well as pathogenic microorganisms will result from the diversified human, industrial and agricultural activities. Anaerobic digestion is applauded as one of the best ways to properly handle and manage these wastes. Animal wastes have been recognized as suitable substrates for anaerobic digestion process, a natural biological process in which complex organic materials are broken down into simpler molecules in the absence of oxygen by the concerted activities of four sets of metabolically linked microorganisms. This process occurs in an airtight chamber (biodigester) via four stages represented by hydrolytic, acidogenic, acetogenic and methanogenic microorganisms. The microbial population and structure can be identified by the combined use of culture-based, microscopic and molecular techniques. Overall, the process is affected by bio-digester design, operational factors and manure characteristics. The purpose of anaerobic digestion is the production of a renewable energy source (biogas) and an odor free nutrient-rich fertilizer. Conversely, if animal wastes are accidentally found in the environment, it can cause a drastic chain of environmental and public health complications. PMID:24048207

  14. Microbial anaerobic digestion (bio-digesters) as an approach to the decontamination of animal wastes in pollution control and the generation of renewable energy.

    Science.gov (United States)

    Manyi-Loh, Christy E; Mamphweli, Sampson N; Meyer, Edson L; Okoh, Anthony I; Makaka, Golden; Simon, Michael

    2013-09-17

    With an ever increasing population rate; a vast array of biomass wastes rich in organic and inorganic nutrients as well as pathogenic microorganisms will result from the diversified human, industrial and agricultural activities. Anaerobic digestion is applauded as one of the best ways to properly handle and manage these wastes. Animal wastes have been recognized as suitable substrates for anaerobic digestion process, a natural biological process in which complex organic materials are broken down into simpler molecules in the absence of oxygen by the concerted activities of four sets of metabolically linked microorganisms. This process occurs in an airtight chamber (biodigester) via four stages represented by hydrolytic, acidogenic, acetogenic and methanogenic microorganisms. The microbial population and structure can be identified by the combined use of culture-based, microscopic and molecular techniques. Overall, the process is affected by bio-digester design, operational factors and manure characteristics. The purpose of anaerobic digestion is the production of a renewable energy source (biogas) and an odor free nutrient-rich fertilizer. Conversely, if animal wastes are accidentally found in the environment, it can cause a drastic chain of environmental and public health complications.

  15. Microbial Anaerobic Digestion (Bio-Digesters as an Approach to the Decontamination of Animal Wastes in Pollution Control and the Generation of Renewable Energy

    Directory of Open Access Journals (Sweden)

    Golden Makaka

    2013-09-01

    Full Text Available With an ever increasing population rate; a vast array of biomass wastes rich in organic and inorganic nutrients as well as pathogenic microorganisms will result from the diversified human, industrial and agricultural activities. Anaerobic digestion is applauded as one of the best ways to properly handle and manage these wastes. Animal wastes have been recognized as suitable substrates for anaerobic digestion process, a natural biological process in which complex organic materials are broken down into simpler molecules in the absence of oxygen by the concerted activities of four sets of metabolically linked microorganisms. This process occurs in an airtight chamber (biodigester via four stages represented by hydrolytic, acidogenic, acetogenic and methanogenic microorganisms. The microbial population and structure can be identified by the combined use of culture-based, microscopic and molecular techniques. Overall, the process is affected by bio-digester design, operational factors and manure characteristics. The purpose of anaerobic digestion is the production of a renewable energy source (biogas and an odor free nutrient-rich fertilizer. Conversely, if animal wastes are accidentally found in the environment, it can cause a drastic chain of environmental and public health complications.

  16. Mass and Energy Balances of Dry Thermophilic Anaerobic Digestion Treating Swine Manure Mixed with Rice Straw

    OpenAIRE

    Sheng Zhou; Jining Zhang; Guoyan Zou; Shohei Riya; Masaaki Hosomi

    2015-01-01

    To evaluate the feasibility of swine manure treatment by a proposed Dry Thermophilic Anaerobic Digestion (DT-AD) system, we evaluated the methane yield of swine manure treated using a DT-AD method with rice straw under different C/N ratios and solid retention time (SRT) and calculated the mass and energy balances when the DT-AD system is used for swine manure treatment from a model farm with 1000 pigs and the digested residue is used for forage rice production. A traditional swine manure trea...

  17. Macroscopic mass and energy balance of a pilot plant anaerobic bioreactor operated under thermophilic conditions.

    Science.gov (United States)

    Espinosa-Solares, Teodoro; Bombardiere, John; Chatfield, Mark; Domaschko, Max; Easter, Michael; Stafford, David A; Castillo-Angeles, Saul; Castellanos-Hernandez, Nehemias

    2006-01-01

    Intensive poultry production generates over 100,000 t of litter annually in West Virginia and 9 x 10(6) t nationwide. Current available technological alternatives based on thermophilic anaerobic digestion for residuals treatment are diverse. A modification of the typical continuous stirred tank reactor is a promising process being relatively stable and owing to its capability to manage considerable amounts of residuals at low operational cost. A 40-m3 pilot plant digester was used for performance evaluation considering energy input and methane production. Results suggest some changes to the pilot plant configuration are necessary to reduce power consumption although maximizing biodigester performance.

  18. Human muscle net K+ release during exercise is unaffected by elevated anaerobic metabolism, but reduced after prolonged acclimatization to 4100 m

    DEFF Research Database (Denmark)

    Nordsborg, Nikolai Baastrup; Calbet, Jose A. L.; Sander, Mikael;

    2010-01-01

    It was investigated if skeletal muscle K(+) release is linked to the degree of anaerobic energy production. Six subjects performed an incremental bicycle exercise test in normoxic and hypoxic conditions prior to and after 2 and 8 weeks of acclimatization to 4100 m. The highest workload completed ...

  19. Role of interleukin 1 and tumor necrosis factor on energy metabolism in rabbits

    International Nuclear Information System (INIS)

    A study of the combined effects of intravenous infusion of the recombinant cytokines beta-interleukin 1 (IL-1) and alpha-tumor necrosis factor (TNF) on energy substrate metabolism in awake, conditioned, adult rabbits was performed. After a 2-h basal or control period, 48-h fasted rabbits were administered TNF and IL-1 as a bolus (5 micrograms/kg) followed by a continuous intravenous infusion (25 ng.kg-1.min-1) for 3 h. Significant increases in plasma lactate (P less than 0.01), glucose (P less than 0.01), and triglycerides (P less than 0.05) occurred during the combined infusion of IL-1 and TNF, whereas neither cytokine alone had no effect. There was a 33% increase in the rate of glucose appearance (P less than 0.05), but glucose clearance was not altered compared with the control period. Glucose oxidation increased during the combined cytokine infusion period and glucose recycling increased by 600% (P less than 0.002). Lactic acidosis and decreased oxygen consumption, as a result of the cytokine infusions, indicated development of anaerobic glycolytic metabolism. A reduction in the activity state of hepatic mitochondrial pyruvate dehydrogenase (65 vs. 82% in control animals, P less than 0.05) was consistent with the observed increase in anaerobic glycolysis. Thus the combined infusion of IL-1 and TNF in rabbits produces metabolic manifestations seen in severe injury and sepsis in human patients and, as such, may account for the profound alterations of energy metabolism seen in these conditions

  20. Reconstitution of dewatered food processing residuals with manure to increase energy production from anaerobic digestion

    International Nuclear Information System (INIS)

    Solid residuals generated from dewatering food processing wastewater contain organic carbon that can potentially be reclaimed for energy through anaerobic digestion. This results in the diversion of waste from a landfill and uses it for a beneficial purpose. Dewatering the waste concentrates the carbon, reducing transportation costs to a farm digester where it can be blended with manure to increase biogas yield. Polymers are often used in the dewatering of the food waste but little is known regarding their impact on biogas production. Four 2 dm3 working volume, semi-continuous reactors, were used at a mesophilic temperature and a solids retention time (SRT) of 15 days. Reactors were fed daily with a blended feedstock containing a food processing sludge waste (FPSW)/manure ratio of 2.2:1 (by weight) as this produced the optimized carbon to nitrogen ratio. Results demonstrated that reconstitution of dewatered FPSW with dairy manure produced approximately 2 times more methane than animal manure alone for the same volume. However, only approximately 30% of volatile solids (VS) were consumed indicating energy potential still remained. Further, the efficiency of the conversion of VS to methane for the blended FPSW/manure was substantially less than for manure only. However, the overall result is an increase in energy production for a given tank volume, which can decrease life cycle costs. Because all FPSW is unique and the determination of dewatering additives is customized based on laboratory testing and field adjustment, generalizations are difficult and specific testing is required. -- Highlights: ► Energy production in anaerobic digestion can increase by co-blending food waste. ► Energy for transporting food waste to blend with manure is less when dewatered. ► Dewatered food waste in manure produced twice as much methane than manure. ► Efficiency of carbon to methane was low because of ammonium bicarbonate production. ► Carbon destruction was 30%, more

  1. Limits to anaerobic energy and cytosolic concentration in the living cell

    Science.gov (United States)

    Paglietti, A.

    2015-11-01

    For many physical systems at any given temperature, the set of all states where the system's free energy reaches its largest value can be determined from the system's constitutive equations of internal energy and entropy, once a state of that set is known. Such an approach is fraught with complications when applied to a living cell, because the cell's cytosol contains thousands of solutes, and thus thousands of state variables, which makes determination of its state impractical. We show here that, when looking for the maximum energy that the cytosol can store and release, detailed information on cytosol composition is redundant. Compatibility with cell's life requires that a single variable that represents the overall concentration of cytosol solutes must fall between defined limits, which can be determined by dehydrating and overhydrating the cell to its maximum capacity. The same limits are shown to determine, in particular, the maximum amount of free energy that a cell can supply in fast anaerobic processes, starting from any given initial state. For a typical skeletal muscle in normal physiological conditions this energy, i.e., the maximum anaerobic capacity to do work, is calculated to be about 960 J per kg of muscular mass. Such energy decreases as the overall concentration of solutes in the cytosol is increased. Similar results apply to any kind of cell. They provide an essential tool to understand and control the macroscopic response of single cells and multicellular cellular tissues alike. The applications include sport physiology, cell aging, disease produced cell damage, drug absorption capacity, to mention the most obvious ones.

  2. Energy metabolism in the acquisition and maintenance of stemness.

    Science.gov (United States)

    Folmes, Clifford D L; Terzic, Andre

    2016-04-01

    Energy metabolism is traditionally considered a reactive homeostatic system addressing stage-specific cellular energy needs. There is however growing appreciation of metabolic pathways in the active control of vital cell functions. Case in point, the stem cell lifecycle--from maintenance and acquisition of stemness to lineage commitment and specification--is increasingly recognized as a metabolism-dependent process. Indeed, metabolic reprogramming is an early contributor to the orchestrated departure from or reacquisition of stemness. Recent advances in metabolomics have helped decipher the identity and dynamics of metabolic fluxes implicated in fueling cell fate choices by regulating the epigenetic and transcriptional identity of a cell. Metabolic cues, internal and/or external to the stem cell niche, facilitate progenitor pool restitution, long-term tissue renewal or ensure adoption of cytoprotective behavior. Convergence of energy metabolism with stem cell fate regulation opens a new avenue in understanding primordial developmental biology principles with future applications in regenerative medicine practice. PMID:26868758

  3. Establishment and metabolic analysis of a model microbial community for understanding trophic and electron accepting interactions of subsurface anaerobic environments

    Directory of Open Access Journals (Sweden)

    Yang Zamin K

    2010-05-01

    Full Text Available Abstract Background Communities of microorganisms control the rates of key biogeochemical cycles, and are important for biotechnology, bioremediation, and industrial microbiological processes. For this reason, we constructed a model microbial community comprised of three species dependent on trophic interactions. The three species microbial community was comprised of Clostridium cellulolyticum, Desulfovibrio vulgaris Hildenborough, and Geobacter sulfurreducens and was grown under continuous culture conditions. Cellobiose served as the carbon and energy source for C. cellulolyticum, whereas D. vulgaris and G. sulfurreducens derived carbon and energy from the metabolic products of cellobiose fermentation and were provided with sulfate and fumarate respectively as electron acceptors. Results qPCR monitoring of the culture revealed C. cellulolyticum to be dominant as expected and confirmed the presence of D. vulgaris and G. sulfurreducens. Proposed metabolic modeling of carbon and electron flow of the three-species community indicated that the growth of C. cellulolyticum and D. vulgaris were electron donor limited whereas G. sulfurreducens was electron acceptor limited. Conclusions The results demonstrate that C. cellulolyticum, D. vulgaris, and G. sulfurreducens can be grown in coculture in a continuous culture system in which D. vulgaris and G. sulfurreducens are dependent upon the metabolic byproducts of C. cellulolyticum for nutrients. This represents a step towards developing a tractable model ecosystem comprised of members representing the functional groups of a trophic network.

  4. High-intensity interval training, solutions to the programming puzzle. Part II: anaerobic energy, neuromuscular load and practical applications.

    Science.gov (United States)

    Buchheit, Martin; Laursen, Paul B

    2013-10-01

    High-intensity interval training (HIT) is a well-known, time-efficient training method for improving cardiorespiratory and metabolic function and, in turn, physical performance in athletes. HIT involves repeated short (<45 s) to long (2-4 min) bouts of rather high-intensity exercise interspersed with recovery periods (refer to the previously published first part of this review). While athletes have used 'classical' HIT formats for nearly a century (e.g. repetitions of 30 s of exercise interspersed with 30 s of rest, or 2-4-min interval repetitions ran at high but still submaximal intensities), there is today a surge of research interest focused on examining the effects of short sprints and all-out efforts, both in the field and in the laboratory. Prescription of HIT consists of the manipulation of at least nine variables (e.g. work interval intensity and duration, relief interval intensity and duration, exercise modality, number of repetitions, number of series, between-series recovery duration and intensity); any of which has a likely effect on the acute physiological response. Manipulating HIT appropriately is important, not only with respect to the expected middle- to long-term physiological and performance adaptations, but also to maximize daily and/or weekly training periodization. Cardiopulmonary responses are typically the first variables to consider when programming HIT (refer to Part I). However, anaerobic glycolytic energy contribution and neuromuscular load should also be considered to maximize the training outcome. Contrasting HIT formats that elicit similar (and maximal) cardiorespiratory responses have been associated with distinctly different anaerobic energy contributions. The high locomotor speed/power requirements of HIT (i.e. ≥95 % of the minimal velocity/power that elicits maximal oxygen uptake [v/p(·)VO(2max)] to 100 % of maximal sprinting speed or power) and the accumulation of high-training volumes at high-exercise intensity (runners can

  5. Anaerobic digestion of paunch in a CSTR for renewable energy production and nutrient mineralization

    Energy Technology Data Exchange (ETDEWEB)

    Nkemka, Valentine Nkongndem; Marchbank, Douglas H.; Hao, Xiying, E-mail: xiying.hao@agr.gc.ca

    2015-09-15

    Highlights: • Anaerobic digestion and nutrient mineralization of paunch in a CSTR. • Low CH{sub 4} yield and high CH{sub 4} productivity was obtained at an OLR of 2.8 g VS L{sup −1} day{sup −1.} • Post-digestion of the digestate resulted in a CH{sub 4} yield of 0.067 L g{sup −1} VS. • Post-digestion is recommended for further digestate stabilization. - Abstract: A laboratory study investigated the anaerobic digestion of paunch in a continuous stirred tank reactor (CSTR) for the recovery of biogas and mineralization of nutrients. At an organic loading rate (OLR) of 2.8 g VS L{sup −1} day{sup −1} with a 30-day hydraulic retention time (HRT), a CH{sub 4} yield of 0.213 L g{sup −1} VS and CH{sub 4} production rate of 0.600 L L{sup −1} day{sup −1} were obtained. Post-anaerobic digestion of the effluent from the CSTR for 30 days at 40 °C recovered 0.067 L g{sup −1} VS as CH{sub 4}, which was 21% of the batch CH{sub 4} potential. Post-digestion of the effluent from the digestate obtained at this OLR is needed to meet the stable effluent criteria. Furthermore, low levels of soluble ions such as K{sup +}, Ca{sup 2+} and Mg{sup 2+} were found in the liquid fraction of the digestate and the remainder could have been retained in the solid digestate fraction. This study demonstrates the potential of biogas production from paunch in providing renewable energy. In addition, recovery of plant nutrients in the digestate is important for a sustainable agricultural system.

  6. Anaerobic digestion of paunch in a CSTR for renewable energy production and nutrient mineralization

    International Nuclear Information System (INIS)

    Highlights: • Anaerobic digestion and nutrient mineralization of paunch in a CSTR. • Low CH4 yield and high CH4 productivity was obtained at an OLR of 2.8 g VS L−1 day−1. • Post-digestion of the digestate resulted in a CH4 yield of 0.067 L g−1 VS. • Post-digestion is recommended for further digestate stabilization. - Abstract: A laboratory study investigated the anaerobic digestion of paunch in a continuous stirred tank reactor (CSTR) for the recovery of biogas and mineralization of nutrients. At an organic loading rate (OLR) of 2.8 g VS L−1 day−1 with a 30-day hydraulic retention time (HRT), a CH4 yield of 0.213 L g−1 VS and CH4 production rate of 0.600 L L−1 day−1 were obtained. Post-anaerobic digestion of the effluent from the CSTR for 30 days at 40 °C recovered 0.067 L g−1 VS as CH4, which was 21% of the batch CH4 potential. Post-digestion of the effluent from the digestate obtained at this OLR is needed to meet the stable effluent criteria. Furthermore, low levels of soluble ions such as K+, Ca2+ and Mg2+ were found in the liquid fraction of the digestate and the remainder could have been retained in the solid digestate fraction. This study demonstrates the potential of biogas production from paunch in providing renewable energy. In addition, recovery of plant nutrients in the digestate is important for a sustainable agricultural system

  7. A Cellular Perspective on Brain Energy Metabolism and Functional Imaging

    KAUST Repository

    Magistretti, Pierre J.

    2015-05-01

    The energy demands of the brain are high: they account for at least 20% of the body\\'s energy consumption. Evolutionary studies indicate that the emergence of higher cognitive functions in humans is associated with an increased glucose utilization and expression of energy metabolism genes. Functional brain imaging techniques such as fMRI and PET, which are widely used in human neuroscience studies, detect signals that monitor energy delivery and use in register with neuronal activity. Recent technological advances in metabolic studies with cellular resolution have afforded decisive insights into the understanding of the cellular and molecular bases of the coupling between neuronal activity and energy metabolism and pointat a key role of neuron-astrocyte metabolic interactions. This article reviews some of the most salient features emerging from recent studies and aims at providing an integration of brain energy metabolism across resolution scales. © 2015 Elsevier Inc.

  8. Metabolic restructuring during energy-limited states: insights from Artemia franciscana embryos and other animals.

    Science.gov (United States)

    Hand, Steven C; Menze, Michael A; Borcar, Apu; Patil, Yuvraj; Covi, Joseph A; Reynolds, Julie A; Toner, Mehmet

    2011-05-01

    Many life history stages of animals that experience environmental insults enter developmental arrested states that are characterized by reduced cellular proliferation, with or without a concurrent reduction in overall metabolism. In the case of the most profound metabolic arrest reported in invertebrates, i.e., anaerobic quiescence in Artemia franciscana embryos, acidification of the intracellular milieu is a major factor governing catabolic and anabolic downregulation. Release of ions from intracellular compartments is the source for approximately 50% of the proton equivalents needed for the 1.5 unit acidification that is observed. Recovery from the metabolic arrest requires re-sequestration of the protons with a vacuolar-type ATPase (V-ATPase). The remarkable facet of this mechanism is the ability of embryonic cells to survive the dissipation of intracellular ion gradients. Across many diapause-like states, the metabolic reduction and subsequent matching of energy demand is accomplished by shifting energy metabolism from oxidative phosphorylation to aerobic glycolysis. Molecular pathways that are activated to induce these resilient hypometabolic states include stimulation of the AMP-activated protein kinase (AMPK) and insulin signaling via suite of daf (dauer formation) genes for diapause-like states in nematodes and insects. Contributing factors for other metabolically depressed states involve hypoxia-inducible factor-1 and downregulation of the pyruvate dehydrogenase complex. Metabolic similarities between natural states of stasis and some cancer phenotypes are noteworthy. Reduction of flux through oxidative phosphorylation helps prevent cell death in certain cancer types, similar to the way it increases viability of dauer stages in Caenorhabditis elegans. Mechanisms that underlie natural stasis are being used to pre-condition mammalian cells prior to cell biostabilization and storage.

  9. Inborn Errors of Energy Metabolism Associated with Myopathies

    OpenAIRE

    Das, Anibh M.; Ulrike Steuerwald; Sabine Illsinger

    2010-01-01

    Inherited neuromuscular disorders affect approximately one in 3,500 children. Structural muscular defects are most common; however functional impairment of skeletal and cardiac muscle in both children and adults may be caused by inborn errors of energy metabolism as well. Patients suffering from metabolic myopathies due to compromised energy metabolism may present with exercise intolerance, muscle pain, reversible or progressive muscle weakness, and myoglobinuria. In this review, the physiolo...

  10. Respiration, respiratory metabolism and energy consumption under weightless conditions

    Science.gov (United States)

    Kasyan, I. I.; Makarov, G. F.

    1975-01-01

    Changes in the physiological indices of respiration, respiratory metabolism and energy consumption in spacecrews under weightlessness conditions manifest themselves in increased metabolic rates, higher pulmonary ventilation volume, oxygen consumption and carbon dioxide elimination, energy consumption levels in proportion to reduction in neuroemotional and psychic stress, adaptation to weightlessness and work-rest cycles, and finally in a relative stabilization of metabolic processes due to hemodynamic shifts.

  11. ASSESSMENT OF WASTE TREATMENT AND ENERGY RECOVERY FROM DAIRY INDUSTRIAL WASTE BY ANAEROBIC DIGESTION

    Directory of Open Access Journals (Sweden)

    Richa Kothari, Virendra Kumar, and Vineet Veer Tyagi

    2011-01-01

    Full Text Available Waste treatment with simultaneous energy generation was studied in anaerobic digester using dairy industry waste (sludge, influent as substrate. No pretreatment or solid liquid separation was applied. Batch fermentation experiments were performed with three different substrates at organic pollution load (OPL under mesophilic range of temperature (30_+C. Experimental data evidence the effectiveness of waste on both the removal efficiency in terms of substrate degradation and biogas yield, particularly at higher loading rates. Among the three substrates evaluated, alternative substrates showed comparatively effective performance in comparison to conventional one. However, COD removal efficiency was also found to be effective in operated environment. The described process provides the dual benefit of waste treatment with simultaneous green energy generation in the form of biogas utilizing it as substrate.

  12. Environmental assessment of energy and waste systems based on anaerobic digestion

    Energy Technology Data Exchange (ETDEWEB)

    Rehl, Torsten

    2013-08-01

    The results of the studies show that biogas production brings about many or environmental improvements compared to energy generation based on fossil sources when designed and managed properly. Environmental advantages are found for GWP (Global Warming Potential) and energy consumption, disadvantages however for EP (Eutrophication Potential), AP (Acidification Potential) and POCP (Photochemical Ozone Creation Potential). However the large amount of technologies and measures indicate that there is a large potential to reduce the environmental impacts. Another finding is that all life cycle phases and subsystems must be carefully considered, as no single dominating item or aspect in the life cycle can be identified. The most environmentally relevant phases are found to be storage, treatment and field application of manure and digestate. This result is to a large part due to the emission of ammonia, nitrous oxide and nitrate. It can therefore be concluded that from a lifecycle perspective, control and mitigation of nitrogen related emissions will be of utmost importance in the future to improve the environmental performance of biogas systems. Considerable emission reduction potentials are exposed when proper technological modifications (e.g. storage covers, filter technologies, digestate treatment or field application technologies) or adopted management practices (early soil incorporation of digestate) are applied. The environmental analysis also shows that whenever possible the focus of anaerobic digestion should be on the use of organic residues from households, agriculture or food industry instead of using energy crops. In this case conventional waste management systems are replaced and manifold positive effects of anaerobic digestion such as waste stabilization, nutrient recycling and energy generation emerge.

  13. A comparative genomic analysis of energy metabolism in sulfate reducing bacteria and archaea

    Directory of Open Access Journals (Sweden)

    Inês A. C. ePereira

    2011-04-01

    Full Text Available The number of sequenced genomes of sulfate-reducing organisms (SRO has increased significantly in the recent years, providing an opportunity for a broader perspective into the energy metabolism of such organisms. In this work we carried out a comparative survey of energy metabolism genes found in twenty-five available genomes of SRO. This analysis revealed a higher diversity of possible energy conserving pathways than classically considered to be present in these organisms, and permitted the identification of new proteins not known to be present in this group. The Deltaproteobacteria (and Thermodesulfovibrio yellowstonii are characterized by a large number of cytochromes c and cytochrome c-associated membrane redox complexes, indicating that periplasmic electron transfer pathways are important in these bacteria. The Archaea and Clostridia groups contain practically no cytochromes c or associated membrane complexes. However, despite the absence of a periplasmic space, a few extracytoplasmic membrane redox proteins were detected in the Gram-positive bacteria. Several ion-translocating complexes were detected in SRO including H+-pyrophosphatases, complex I homologues, Rnf and Ech/Coo hydrogenases. Furthermore, we found evidence that cytoplasmic electron bifurcating mechanisms, recently described for other anaerobes, are also likely to play an important role in energy metabolism of SRO. A number of cytoplasmic [NiFe] and [FeFe] hydrogenases, formate dehydrogenases and heterodisulfide reductase-related proteins are likely candidates to be involved in energy coupling through electron bifurcation, from diverse electron donors such as H2, formate, pyruvate, NAD(PH, β-oxidation and others. In conclusion, this analysis indicates that energy metabolism of SRO is far more versatile than previously considered, and that both chemiosmotic and flavin-based electron bifurcating mechanisms provide alternative strategies for energy conservation.

  14. Anaerobic digestion of paunch in a CSTR for renewable energy production and nutrient mineralization.

    Science.gov (United States)

    Nkemka, Valentine Nkongndem; Marchbank, Douglas H; Hao, Xiying

    2015-09-01

    A laboratory study investigated the anaerobic digestion of paunch in a continuous stirred tank reactor (CSTR) for the recovery of biogas and mineralization of nutrients. At an organic loading rate (OLR) of 2.8gVSL(-1)day(-1) with a 30-day hydraulic retention time (HRT), a CH4 yield of 0.213Lg(-1)VS and CH4 production rate of 0.600LL(-1)day(-1) were obtained. Post-anaerobic digestion of the effluent from the CSTR for 30days at 40°C recovered 0.067Lg(-1)VS as CH4, which was 21% of the batch CH4 potential. Post-digestion of the effluent from the digestate obtained at this OLR is needed to meet the stable effluent criteria. Furthermore, low levels of soluble ions such as K(+), Ca(2+) and Mg(2+) were found in the liquid fraction of the digestate and the remainder could have been retained in the solid digestate fraction. This study demonstrates the potential of biogas production from paunch in providing renewable energy. In addition, recovery of plant nutrients in the digestate is important for a sustainable agricultural system.

  15. An integrated approach to energy recovery from biomass and waste: Anaerobic digestion-gasification-water treatment.

    Science.gov (United States)

    Milani, M; Montorsi, L; Stefani, M

    2014-06-19

    The article investigates the performance of an integrated system for the energy recovery from biomass and waste based on anaerobic digestion, gasification and water treatment. In the proposed system, the organic fraction of waste of the digestible biomass is fed into an anaerobic digester, while a part of the combustible fraction of the municipal solid waste is gasified. Thus, the obtained biogas and syngas are used as a fuel for running a cogeneration system based on an internal combustion engine to produce electric and thermal power. The waste water produced by the integrated plant is recovered by means of both forward and inverse osmosis. The different processes, as well as the main components of the system, are modelled by means of a lumped and distributed parameter approach and the main outputs of the integrated plant such as the electric and thermal power and the amount of purified water are calculated. Finally, the implementation of the proposed system is evaluated for urban areas with a different number of inhabitants and the relating performance is estimated in terms of the main outputs of the system. PMID:24946772

  16. Anaerobic codigestion of dairy manure and food manufacturing waste for renewable energy generation in New York State

    Science.gov (United States)

    Rankin, Matthew J.

    Anaerobic digestion is a microbiological process that converts biodegradable organic material into biogas, consisting primarily of methane and carbon dioxide. Anaerobic digestion technologies have been integrated into wastewater treatment facilities nationwide for many decades to increase the economic viability of the treatment process by converting a waste stream into two valuable products: biogas and fertilizer. Thus, anaerobic digestion offers potential economic and environmental benefits of organic waste diversion and renewable energy generation. The use of biogas has many applications, including cogeneration, direct combustion, upgrading for conversion to feed a fuel cell, and compression for injection into the natural gas grid or for vehicular use. The potential benefits of waste diversion and renewable energy generation are now being realized by major organic waste generators in New York State, in particular the food manufacturing and dairy industries, thus warranting an analysis of the energy generation potential for these waste products. Anaerobic codigestion of dairy manure and food-based feedstocks reflects a cradle-to- cradle approach to organic waste management. Given both of their abundance throughout New York State, waste-to-energy processes represent promising waste management strategies. The objective of this thesis was to evaluate the current technical and economic feasibility of anaerobically codigesting existing dairy manure and food manufacturing waste feedstocks in New York State to produce high quality biogas for renewable energy generation. The first element to determining the technical feasibility of anaerobic codigestion potential in New York State was to first understand the feedstock availability. A comprehensive survey of existing organic waste streams was conducted. The key objective was to identify the volume and composition of dairy manure and liquid-phase food manufacturing waste streams available in New York State to make

  17. Anaerobic workout

    OpenAIRE

    McAdam, Ewan J.

    2010-01-01

    Anaerobic technology cannot directly replace current wastewater treatment processes exclusively. The UASB reactor configuration removes slightly less organic carbon by comparison as the process relies on lamella separation for passive clarification rather than using fine pores like anMBR. By contrast, whilst anMBR can operate as a single unit process for organic carbon removal, the membrane surface has to be cleaned using gas sparging to limit surface deposition, which requires extra energy. ...

  18. Aspects of astrocyte energy metabolism, amino acid neurotransmitter homoeostasis and metabolic compartmentation

    Directory of Open Access Journals (Sweden)

    Marko Kreft

    2012-04-01

    Full Text Available Astrocytes are key players in brain function; they are intimately involved in neuronal signalling processes and their metabolism is tightly coupled to that of neurons. In the present review, we will be concerned with a discussion of aspects of astrocyte metabolism, including energy-generating pathways and amino acid homoeostasis. A discussion of the impact that uptake of neurotransmitter glutamate may have on these pathways is included along with a section on metabolic compartmentation.

  19. Mass and Energy Balances of Dry Thermophilic Anaerobic Digestion Treating Swine Manure Mixed with Rice Straw

    Directory of Open Access Journals (Sweden)

    Sheng Zhou

    2015-01-01

    Full Text Available To evaluate the feasibility of swine manure treatment by a proposed Dry Thermophilic Anaerobic Digestion (DT-AD system, we evaluated the methane yield of swine manure treated using a DT-AD method with rice straw under different C/N ratios and solid retention time (SRT and calculated the mass and energy balances when the DT-AD system is used for swine manure treatment from a model farm with 1000 pigs and the digested residue is used for forage rice production. A traditional swine manure treatment Oxidation Ditch system was used as the study control. The results suggest that methane yield using the proposed DT-AD system increased with a higher C/N ratio and shorter SRT. Correspondently, for the DT-AD system running with SRT of 80 days, the net energy yields for all treatments were negative, due to low biogas production and high heat loss of digestion tank. However, the biogas yield increased when the SRT was shortened to 40 days, and the generated energy was greater than consumed energy when C/N ratio was 20:1 and 30:1. The results suggest that with the correct optimization of C/N ratio and SRT, the proposed DT-AD system, followed by using digestate for forage rice production, can attain energy self-sufficiency.

  20. DEMONSTRATION OF FUEL CELLS TO RECOVER ENERGY FROM ANAEROBIC DIGESTER GAS - PHASE I. CONCEPTUAL DESIGN, PRELIMINARY COST, AND EVALUATION STUDY

    Science.gov (United States)

    The report discusses Phase I (a conceptual design, preliminary cost, and evaluation study) of a program to demonstrate the recovery of energy from waste methane produced by anaerobic digestion of waste water treatment sludge. The fuel cell is being used for this application becau...

  1. Adaptations in the energy metabolism of parasites

    NARCIS (Netherlands)

    van Grinsven, K.W.A.

    2009-01-01

    For this thesis fundamental research was performed on the metabolic adaptations found in parasites. Studying the adaptations in parasite metabolisms leads to a better understanding of parasite bioenergetics and can also result in the identification of new anti-parasitic drug targets. We focussed on

  2. Metabolism as a tool for understanding human brain evolution: lipid energy metabolism as an example.

    Science.gov (United States)

    Wang, Shu Pei; Yang, Hao; Wu, Jiang Wei; Gauthier, Nicolas; Fukao, Toshiyuki; Mitchell, Grant A

    2014-12-01

    Genes and the environment both influence the metabolic processes that determine fitness. To illustrate the importance of metabolism for human brain evolution and health, we use the example of lipid energy metabolism, i.e. the use of fat (lipid) to produce energy and the advantages that this metabolic pathway provides for the brain during environmental energy shortage. We briefly describe some features of metabolism in ancestral organisms, which provided a molecular toolkit for later development. In modern humans, lipid energy metabolism is a regulated multi-organ pathway that links triglycerides in fat tissue to the mitochondria of many tissues including the brain. Three important control points are each suppressed by insulin. (1) Lipid reserves in adipose tissue are released by lipolysis during fasting and stress, producing fatty acids (FAs) which circulate in the blood and are taken up by cells. (2) FA oxidation. Mitochondrial entry is controlled by carnitine palmitoyl transferase 1 (CPT1). Inside the mitochondria, FAs undergo beta oxidation and energy production in the Krebs cycle and respiratory chain. (3) In liver mitochondria, the 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) pathway produces ketone bodies for the brain and other organs. Unlike most tissues, the brain does not capture and metabolize circulating FAs for energy production. However, the brain can use ketone bodies for energy. We discuss two examples of genetic metabolic traits that may be advantageous under most conditions but deleterious in others. (1) A CPT1A variant prevalent in Inuit people may allow increased FA oxidation under nonfasting conditions but also predispose to hypoglycemic episodes. (2) The thrifty genotype theory, which holds that energy expenditure is efficient so as to maximize energy stores, predicts that these adaptations may enhance survival in periods of famine but predispose to obesity in modern dietary environments.

  3. A plant-wide energy model for wastewater treatment plants: application to anaerobic membrane bioreactor technology.

    Science.gov (United States)

    Pretel, R; Robles, A; Ruano, M V; Seco, A; Ferrer, J

    2016-09-01

    The aim of this study is to propose a detailed and comprehensive plant-wide model for assessing the energy demand of different wastewater treatment systems (beyond the traditional activated sludge) in both steady- and unsteady-state conditions. The proposed model makes it possible to calculate power and heat requirements (W and Q, respectively), and to recover both power and heat from methane and hydrogen capture. In order to account for the effect of biological processes on heat requirements, the model has been coupled to the extended version of the BNRM2 plant-wide mathematical model, which is implemented in DESSAS simulation software. Two case studies have been evaluated to assess the model's performance: (1) modelling the energy demand of two urban wastewater treatment plants based on conventional activated sludge and submerged anaerobic membrane bioreactor (AnMBR) technologies in steady-state conditions and (2) modelling the dynamics of reactor temperature and heat requirements in an AnMBR plant in unsteady-state conditions. The results indicate that the proposed model can be used to assess the energy performance of different wastewater treatment processes and would thus be useful, for example, WWTP design or upgrading or the development of new control strategies for energy savings. PMID:26829316

  4. Anaerobic digestion of industrial hemp-effect of harvest time on methane energy yield per hectare

    Energy Technology Data Exchange (ETDEWEB)

    Kreuger, E.; Escobar, F.; Bjoernsson, L. [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Prade, T.; Svensson, S.-E.; Englund, J.-E. [Department of Agriculture-Farming Systems, Technology and Product Quality, Swedish University of Agricultural Sciences, P.O. Box 104, SE-230 53 Alnarp (Sweden)

    2011-02-15

    There is a worldwide emphasis to increase the share of renewable transportation fuels. When using agricultural land for production of renewable transportation fuels, the energy output per hectare for different crops and transportation fuels is a crucial factor. In this study, the gross methane energy yield per hectare from anaerobic digestion of industrial hemp (Cannabis sativa L.), was determined at four different harvest times between July and October in Southern Sweden, a cold climate region. The biomass yield was determined for three years and the methane yield was determined for two years through the biochemical methane potential test. The highest biomass yield, 16 tonnes dry matter per hectare on an average, and the highest methane energy yield per hectare was achieved when the hemp was harvested in September or October, with an average gross methane energy yield of 136 {+-} 24 GJ per hectare. There was no significant difference in the specific methane yield between the harvest times; the average being 234 {+-} 35 m{sup 3} per tonne volatile solids. Biogas from hemp turned out to be a high yielding alternative to the currently dominating renewable transportation fuels produced from crops grown in Sweden: ethanol from wheat and biodiesel from rapeseed. (author)

  5. A plant-wide energy model for wastewater treatment plants: application to anaerobic membrane bioreactor technology.

    Science.gov (United States)

    Pretel, R; Robles, A; Ruano, M V; Seco, A; Ferrer, J

    2016-09-01

    The aim of this study is to propose a detailed and comprehensive plant-wide model for assessing the energy demand of different wastewater treatment systems (beyond the traditional activated sludge) in both steady- and unsteady-state conditions. The proposed model makes it possible to calculate power and heat requirements (W and Q, respectively), and to recover both power and heat from methane and hydrogen capture. In order to account for the effect of biological processes on heat requirements, the model has been coupled to the extended version of the BNRM2 plant-wide mathematical model, which is implemented in DESSAS simulation software. Two case studies have been evaluated to assess the model's performance: (1) modelling the energy demand of two urban wastewater treatment plants based on conventional activated sludge and submerged anaerobic membrane bioreactor (AnMBR) technologies in steady-state conditions and (2) modelling the dynamics of reactor temperature and heat requirements in an AnMBR plant in unsteady-state conditions. The results indicate that the proposed model can be used to assess the energy performance of different wastewater treatment processes and would thus be useful, for example, WWTP design or upgrading or the development of new control strategies for energy savings.

  6. Development of an energy-saving anaerobic hybrid membrane bioreactors for 2-chlorophenol-contained wastewater treatment.

    Science.gov (United States)

    Wang, Yun-Kun; Pan, Xin-Rong; Sheng, Guo-Ping; Li, Wen-Wei; Shi, Bing-Jing; Yu, Han-Qing

    2015-12-01

    A novel energy-saving anaerobic hybrid membrane bioreactor (AnHMBR) with mesh filter, which takes advantage of anaerobic membrane bioreactor and fixed-bed biofilm reactor, is developed for low-strength 2-chlorophenol (2-CP)-contained wastewater treatment. In this system, the anaerobic membrane bioreactor is stuffed with granular activated carbon to construct an anaerobic hybrid fixed-bed biofilm membrane bioreactor. The effluent turbidity from the AnHMBR system was low during most of the operation period, and the chemical oxygen demand and 2-CP removal efficiencies averaged 82.3% and 92.6%, respectively. Furthermore, a low membrane fouling rate was achieved during the operation. During the AnHMBR operation, the only energy consumption was for feed pump. And a low energy demand of 0.0045-0.0063kWhm(-3) was estimated under the current operation conditions. All these results demonstrated that this novel AnHMBR is a sustainable technology for treating 2-CP-contained wastewater. PMID:24880609

  7. Development of an energy-saving anaerobic hybrid membrane bioreactors for 2-chlorophenol-contained wastewater treatment.

    Science.gov (United States)

    Wang, Yun-Kun; Pan, Xin-Rong; Sheng, Guo-Ping; Li, Wen-Wei; Shi, Bing-Jing; Yu, Han-Qing

    2015-12-01

    A novel energy-saving anaerobic hybrid membrane bioreactor (AnHMBR) with mesh filter, which takes advantage of anaerobic membrane bioreactor and fixed-bed biofilm reactor, is developed for low-strength 2-chlorophenol (2-CP)-contained wastewater treatment. In this system, the anaerobic membrane bioreactor is stuffed with granular activated carbon to construct an anaerobic hybrid fixed-bed biofilm membrane bioreactor. The effluent turbidity from the AnHMBR system was low during most of the operation period, and the chemical oxygen demand and 2-CP removal efficiencies averaged 82.3% and 92.6%, respectively. Furthermore, a low membrane fouling rate was achieved during the operation. During the AnHMBR operation, the only energy consumption was for feed pump. And a low energy demand of 0.0045-0.0063kWhm(-3) was estimated under the current operation conditions. All these results demonstrated that this novel AnHMBR is a sustainable technology for treating 2-CP-contained wastewater.

  8. Methanosarcina Play an Important Role in Anaerobic Co-Digestion of the Seaweed Ulva lactuca: Taxonomy and Predicted Metabolism of Functional Microbial Communities.

    Directory of Open Access Journals (Sweden)

    Jamie A FitzGerald

    Full Text Available Macro-algae represent an ideal resource of third generation biofuels, but their use necessitates a refinement of commonly used anaerobic digestion processes. In a previous study, contrasting mixes of dairy slurry and the macro-alga Ulva lactuca were anaerobically digested in mesophilic continuously stirred tank reactors for 40 weeks. Higher proportions of U. lactuca in the feedstock led to inhibited digestion and rapid accumulation of volatile fatty acids, requiring a reduced organic loading rate. In this study, 16S pyrosequencing was employed to characterise the microbial communities of both the weakest (R1 and strongest (R6 performing reactors from the previous work as they developed over a 39 and 27-week period respectively. Comparing the reactor communities revealed clear differences in taxonomy, predicted metabolic orientation and mechanisms of inhibition, while constrained canonical analysis (CCA showed ammonia and biogas yield to be the strongest factors differentiating the two reactor communities. Significant biomarker taxa and predicted metabolic activities were identified for viable and failing anaerobic digestion of U. lactuca. Acetoclastic methanogens were inhibited early in R1 operation, followed by a gradual decline of hydrogenotrophic methanogens. Near-total loss of methanogens led to an accumulation of acetic acid that reduced performance of R1, while a slow decline in biogas yield in R6 could be attributed to inhibition of acetogenic rather than methanogenic activity. The improved performance of R6 is likely to have been as a result of the large Methanosarcina population, which enabled rapid removal of acetic acid, providing favourable conditions for substrate degradation.

  9. Aspects of astrocyte energy metabolism, amino acid neurotransmitter homoeostasis and metabolic compartmentation

    DEFF Research Database (Denmark)

    Kreft, Marko; Bak, Lasse Kristoffer; Waagepetersen, Helle S;

    2012-01-01

    Astrocytes are key players in brain function; they are intimately involved in neuronal signalling processes and their metabolism is tightly coupled to that of neurons. In the present review, we will be concerned with a discussion of aspects of astrocyte metabolism, including energy-generating pat......-generating pathways and amino acid homoeostasis. A discussion of the impact that uptake of neurotransmitter glutamate may have on these pathways is included along with a section on metabolic compartmentation.......Astrocytes are key players in brain function; they are intimately involved in neuronal signalling processes and their metabolism is tightly coupled to that of neurons. In the present review, we will be concerned with a discussion of aspects of astrocyte metabolism, including energy...

  10. Energy potential from the anaerobic digestion of food waste in municipal solid waste stream of urban areas in Vietnam

    OpenAIRE

    Nguyen, Hoa Huu; Heaven, Sonia; Banks, Charles

    2014-01-01

    Anaerobic digestion (AD) was introduced in Vietnam more than 10 years ago, but at a small scale to deal with agricultural wastes, manure, etc. Despite its many advantages, AD does not yet make a significant contribution to resolving Vietnams urban waste issues due to a lack of information, data and experience. This paper, using an energy model of food waste digestion, provides a usable source of information regarding energy potential of food waste generated from urban areas in Vietnam in form...

  11. Energy-positive food wastewater treatment using an anaerobic membrane bioreactor (AnMBR).

    Science.gov (United States)

    Galib, Mohamed; Elbeshbishy, Elsayed; Reid, Robertson; Hussain, Abid; Lee, Hyung-Sool

    2016-11-01

    An immersed-membrane anaerobic membrane bioreactor (AnMBR) achieved 88-95% of COD removal for meat-processing wastewater at organic loading rate (OLR) of 0.4-3.2 kgCOD m(-3) d(-1). Membrane flux was stable for low OLR (0.4 and 1.3 kgCOD m(-3) d(-1)), but irrecoverable fouling occurred at high OLR of 3.2 kgCOD m(-3) d(-1). Methane gas yield of 0.13-0.18 LCH4 g(-1)CODremoved was obtained, which accounted for 33-38% of input COD, the most significant electron sink. Dissolved methane was only 3.4-11% of input COD and consistently over-saturated at all OLR conditions. The least accumulation of dissolved methane (25 mg L(-1) and saturation index 1.3) was found for the highest OLR of 3.2 kgCOD m(-3) d(-1) where biogas production rate was the highest. Energy balances showed that AnMBR produced net energy benefit of 0.16-1.82 kWh m(-3), indicating the possibility of energy-positive food wastewater treatment using AnMBRs. PMID:27526085

  12. Metabolic characteristics of anaerobic ammonium oxidizing bacteria with organic matters%有机物作用的厌氧氨氧化菌代谢特性研究进展

    Institute of Scientific and Technical Information of China (English)

    孙佳晶; 张蕾; 张超; 陈晓波

    2012-01-01

    厌氧氨氧化(Anammox)工艺是近年来废水生物脱氮领域的新技术,非常适合于处理含有机物的废水。本文介绍了厌氧氨氧化工艺的特点,详细介绍了有机物对厌氧氨氧化菌的抑制和促进机制。有机物对厌氧氨氧化菌的抑制主要来自两个方面:一是有机物促进异养菌反硝化菌的大量繁殖形成基质竞争抑制;二是废水中的醇类、抗生素等有毒有害有机物会对厌氧氨氧化菌产生毒性抑制。有机物对厌氧氨氧化菌代谢的促进作用也有两种:一是特定的有机物可作为能源被厌氧氨氧化菌利用,促进厌氧氨氧化菌的代谢;二是通过控制废水处理系统中的碳氮比,使厌氧氨氧化菌和反硝化菌在废水处理系统中协同互生。最后指出开发有毒有机废水预处理、驯化厌氧氨氧化污泥、菌种流加等是解决问题的途径。%Anaerobic ammonium oxidation(Anammox),a new biological nitrogen removal process in wastewater treatment,is very suitable for the treatment of wastewater containing organic matters.This paper introduces the characteristics of anaerobic ammonium oxidation process,especially the inhibitive and stimulative mechanisms of organic matters to the bacteria.Two mechanisms are attributed to organic matters induced inhibition,one is heterotrophic denitrifying bacteria promoted by organic matters can compete with anammox bacteria for substrates;the other one is that alcohols,antibiotics and other toxic organics in wastewater leads to toxic inhibition to anaerobic ammonium oxidation bacteria.The stimulation of organic matters to anaerobic ammonium oxidation bacteria also can be explained in two aspects:one is that certain organic matters can be used by anaerobic ammonium oxidation bacteria as energy source,and thus enhance their metabolism;the other is anaerobic ammonium oxidation bacteria and denitrifying bacteria can form symbiote with proper C:N ratio.The pretreatment of

  13. Brain energy metabolism: development and application of novel live methodologies

    OpenAIRE

    Bennett, Rachel

    2012-01-01

    This thesis investigates methods of studying brain energy metabolism with a specific focus on the substrates oxygen and glucose. It details the in vitro development and in vivo characterisation of microelectrochemical sensors for the detection of brain tissue oxygen, and the in vivo characterisation of oxygen and glucose electrodes in the hippocampus utilising the technique of long-term in vivo electrochemistry (LIVE). Chapter 1 introduces the brain, energy metabolism and neurochemical ana...

  14. Modelling chronotaxicity of cellular energy metabolism to facilitate the identification of altered metabolic states

    Science.gov (United States)

    Lancaster, Gemma; Suprunenko, Yevhen F.; Jenkins, Kirsten; Stefanovska, Aneta

    2016-01-01

    Altered cellular energy metabolism is a hallmark of many diseases, one notable example being cancer. Here, we focus on the identification of the transition from healthy to abnormal metabolic states. To do this, we study the dynamics of energy production in a cell. Due to the thermodynamic openness of a living cell, the inability to instantaneously match fluctuating supply and demand in energy metabolism results in nonautonomous time-varying oscillatory dynamics. However, such oscillatory dynamics is often neglected and treated as stochastic. Based on experimental evidence of metabolic oscillations, we show that changes in metabolic state can be described robustly by alterations in the chronotaxicity of the corresponding metabolic oscillations, i.e. the ability of an oscillator to resist external perturbations. We also present a method for the identification of chronotaxicity, applicable to general oscillatory signals and, importantly, apply this to real experimental data. Evidence of chronotaxicity was found in glycolytic oscillations in real yeast cells, verifying that chronotaxicity could be used to study transitions between metabolic states. PMID:27483987

  15. Reducing agitation energy-consumption by improving rheological properties of corn stover substrate in anaerobic digestion.

    Science.gov (United States)

    Tian, Libin; Shen, Fei; Yuan, Hairong; Zou, Dexun; Liu, Yanping; Zhu, Baoning; Li, Xiujin

    2014-09-01

    Rheological properties of corn stover substrate were investigated to explore agitation energy reduction potential for different total solid (TS) in anaerobic digestion. The effects of particle size and temperature on rheological properties and corresponding energy reduction were studied. The results indicated that corn stover slurry exhibited pseudo-plastic flow behavior at TS of 4.23-7.32%, and was well described by Power-law model. At TS of 4.23%, rheological properties were not obviously affected by particle size and temperature. However, when TS was increased to 7.32%, there was 10.37% shear stress reduction by size-reduction from 20 to 80-mesh, and 11.73% shear stress reduction by temperature-increase from 25 to 55 °C. PTS was advanced as variations of power consumption by TS-increase from 4.23% to 7.32%. There was 9.2% PTS-reduction by size-reduction from 20 to 80-mesh at 35 °C. Moreover, PTS-reduction of 10.3%/10 °C was achieved at 20-mesh compared with 9.0%/10 °C at 80-mesh.

  16. Innovative two-stage mesophilic/thermophilic anaerobic degradation of sonicated sludge: performances and energy balance.

    Science.gov (United States)

    Gianico, A; Braguglia, C M; Gallipoli, A; Mininni, G

    2015-05-01

    This study investigates for the first time, on laboratory scale, the possible application of an innovative enhanced stabilization process based on sequential mesophilic/thermophilic anaerobic digestion of waste-activated sludge, with low-energy sonication pretreatment. The first mesophilic digestion step was conducted at short hydraulic retention time (3-5 days), in order to favor volatile fatty acid production, followed by a longer thermophilic step of 10 days to enhance the bioconversion kinetics, assuring a complete pathogen removal. The high volatile solid removals, up to 55%, noticeably higher compared to the performances of a single-stage process carried out in same conditions, can guarantee the stability of the final digestate for land application. The ultrasonic pretreatment influenced significantly the fatty acid formation and composition during the first mesophilic step, improving consequently the thermophilic conversion of these compounds into methane. Methane yield from sonicated sludge digestion reached values up to 0.2 Nm(3)/kgVSfed. Positive energy balances highlighted the possible exploitation of this innovative two-stage digestion in place of conventional single-stage processes. PMID:24906832

  17. Glycerol: An unexpected major metabolite of energy metabolism by the human malaria parasite

    Directory of Open Access Journals (Sweden)

    Bray Patrick G

    2009-03-01

    Full Text Available Abstract Background Malaria is a global health emergency, and yet our understanding of the energy metabolism of the principle causative agent of this devastating disease, Plasmodium falciparum, remains rather basic. Glucose was shown to be an essential nutritional requirement nearly 100 years ago and since this original observation, much of the current knowledge of Plasmodium energy metabolism is based on early biochemical work, performed using basic analytical techniques (e.g. paper chromatography, carried out almost exclusively on avian and rodent malaria. Data derived from malaria parasite genome and transcriptome studies suggest that the energy metabolism of the parasite may be more complex than hitherto anticipated. This study was undertaken in order to further characterize the fate of glucose catabolism in the human malaria parasite, P. falciparum. Methods Products of glucose catabolism were determined by incubating erythrocyte-freed parasites with D-[1-13C] glucose under controlled conditions and metabolites were identified using 13C-NMR spectroscopy. Results Following a 2 h incubation of freed-P. falciparum parasites with 25 mM D-[1-13C] glucose (n = 4, the major metabolites identified included; [3-13C] lactate, [1,3-13C] glycerol, [3-13C] pyruvate, [3-13C] alanine and [3-13C] glycerol-3-phosphate. Control experiments performed with uninfected erythrocytes incubated under identical conditions did not show any metabolism of D-[1-13C] glucose to glycerol or glycerol-3-phosphate. Discussion The identification of glycerol as a major glucose metabolite confirms the view that energy metabolism in this parasite is more complex than previously proposed. It is hypothesized here that glycerol production by the malaria parasite is the result of a metabolic adaptation to growth in O2-limited (and CO2 elevated conditions by the operation of a glycerol-3-phosphate shuttle for the re-oxidation of assimilatory NADH. Similar metabolic adaptations have

  18. Metabolic analysis of the soil microbe Dechloromonas aromatica str. RCB: indications of a surprisingly complex life-style and cryptic anaerobic pathways for aromatic degradation

    Energy Technology Data Exchange (ETDEWEB)

    Salinero, Kennan Kellaris; Keller, Keith; Feil, William S.; Feil, Helene; Trong, Stephan; Di Bartolo, Genevieve; Lapidus, Alla

    2008-11-17

    Initial interest in Dechloromonas aromatica strain RCB arose from its ability to anaerobically degrade benzene. It is also able to reduce perchlorate and oxidize chlorobenzoate, toluene, and xylene, creating interest in using this organism for bioremediation. Little physiological data has been published for this microbe. It is considered to be a free-living organism. The a priori prediction that the D. aromatica genome would contain previously characterized 'central' enzymes involved in anaerobic aromatic degradation proved to be false, suggesting the presence of novel anaerobic aromatic degradation pathways in this species. These missing pathways include the benzyl succinyl synthase (bssABC) genes (responsible for formate addition to toluene) and the central benzoylCoA pathway for monoaromatics. In depth analyses using existing TIGRfam, COG, and InterPro models, and the creation of de novo HMM models, indicate a highly complex lifestyle with a large number of environmental sensors and signaling pathways, including a relatively large number of GGDEF domain signal receptors and multiple quorum sensors. A number of proteins indicate interactions with an as yet unknown host, as indicated by the presence of predicted cell host remodeling enzymes, effector enzymes, hemolysin-like proteins, adhesins, NO reductase, and both type III and type VI secretory complexes. Evidence of biofilm formation including a proposed exopolysaccharide complex with the somewhat rare exosortase (epsH), is also present. Annotation described in this paper also reveals evidence for several metabolic pathways that have yet to be observed experimentally, including a sulphur oxidation (soxFCDYZAXB) gene cluster, Calvin cycle enzymes, and nitrogen fixation (including RubisCo, ribulose-phosphate 3-epimerase, and nif gene families, respectively). Analysis of the D. aromatica genome indicates there is much to be learned regarding the metabolic capabilities, and life-style, for this microbial

  19. Influence of anaesthesia on energy metabolism in surgery

    Directory of Open Access Journals (Sweden)

    Prigorodov М.V.

    2013-03-01

    Full Text Available The purpose of the article is to establish adequacy of protection of energy metabolism in a patient under anaes-thesiology in cholecystectomy from mini-access. Material et methods: 122 patients subjected to cholecystectomy from mini access have been surveyed. Among them 92 patients have got intravenous general anaesthesia with AVL, 30 patients have got prolonged epidural anaesthesia on spontaneous breath with insufflations of oxygen through an obverse mask with sedatations. Monitoring of energy-plastic metabolism has been carried out in all patients. Results: Groups of patients have been compared by anthropometrical data, traumatic interventions. In both groups of patients loss of energy to traumatic to an operation stage has insignificantly increased, but after the anaesthesia termination in the group of patients with intravenous anaesthesia loss of energy continued to rise, and in the group of patients with prolonged epidural blockade it has returned to the initial level. After the anaesthesia termination the energy metabolism became essential higher in the first group of patients in comparison with the second one (p <0,01. The energy-plastic metabolism increased in the first group of patients and decreased in the second. PEA during cholecystectomy from mini access provided a stable condition of energy and energy-plastic metabolism. The conclusion: The inspection of 122 patients subjected to cholecystectomy from mini access has established the following data: PEA on spontaneous breath with insufflations of oxygen through an obverse mask in comparison with intravenous general anaesthesia and AVL allows keeping on an optimum level of energy and energy-plastic metabolism.

  20. Performance evaluation of an anaerobic/aerobic landfill-based digester using yard waste for energy and compost production.

    Science.gov (United States)

    Yazdani, Ramin; Barlaz, Morton A; Augenstein, Don; Kayhanian, Masoud; Tchobanoglous, George

    2012-05-01

    The objective of this study was to evaluate a new alternative for yard waste management by constructing, operating and monitoring a landfill-based two-stage batch digester (anaerobic/aerobic) with the recovery of energy and compost. The system was initially operated under anaerobic conditions for 366 days, after which the yard waste was aerated for an additional 191 days. Off gas generated from the aerobic stage was treated by biofilters. Net energy recovery was 84.3MWh, or 46kWh per million metric tons of wet waste (as received), and the biochemical methane potential of the treated waste decreased by 83% during the two-stage operation. The average removal efficiencies of volatile organic compounds and non-methane organic compounds in the biofilters were 96-99% and 68-99%, respectively.

  1. Microbial catabolic activities are naturally selected by metabolic energy harvest rate.

    Science.gov (United States)

    González-Cabaleiro, Rebeca; Ofiţeru, Irina D; Lema, Juan M; Rodríguez, Jorge

    2015-12-01

    The fundamental trade-off between yield and rate of energy harvest per unit of substrate has been largely discussed as a main characteristic for microbial established cooperation or competition. In this study, this point is addressed by developing a generalized model that simulates competition between existing and not experimentally reported microbial catabolic activities defined only based on well-known biochemical pathways. No specific microbial physiological adaptations are considered, growth yield is calculated coupled to catabolism energetics and a common maximum biomass-specific catabolism rate (expressed as electron transfer rate) is assumed for all microbial groups. Under this approach, successful microbial metabolisms are predicted in line with experimental observations under the hypothesis of maximum energy harvest rate. Two microbial ecosystems, typically found in wastewater treatment plants, are simulated, namely: (i) the anaerobic fermentation of glucose and (ii) the oxidation and reduction of nitrogen under aerobic autotrophic (nitrification) and anoxic heterotrophic and autotrophic (denitrification) conditions. The experimentally observed cross feeding in glucose fermentation, through multiple intermediate fermentation pathways, towards ultimately methane and carbon dioxide is predicted. Analogously, two-stage nitrification (by ammonium and nitrite oxidizers) is predicted as prevailing over nitrification in one stage. Conversely, denitrification is predicted in one stage (by denitrifiers) as well as anammox (anaerobic ammonium oxidation). The model results suggest that these observations are a direct consequence of the different energy yields per electron transferred at the different steps of the pathways. Overall, our results theoretically support the hypothesis that successful microbial catabolic activities are selected by an overall maximum energy harvest rate. PMID:26161636

  2. Recovery of energy and nutrient resources from cattle paunch waste using temperature phased anaerobic digestion.

    Science.gov (United States)

    Jensen, Paul D; Mehta, Chirag M; Carney, Chris; Batstone, D J

    2016-05-01

    Cattle paunch is comprised of partially digested cattle feed, containing mainly grass and grain and is a major waste produced at cattle slaughterhouses contributing 20-30% of organic matter and 40-50% of P waste produced on-site. In this work, Temperature Phased Anaerobic Digestion (TPAD) and struvite crystallization processes were developed at pilot-scale to recover methane energy and nutrients from paunch solid waste. The TPAD plant achieved a maximum sustainable organic loading rate of 1-1.5kgCODm(-3)day(-1) using a feed solids concentration of approximately 3%; this loading rate was limited by plant engineering and not the biology of the process. Organic solids destruction (60%) and methane production (230LCH4kg(-1) VSfed) achieved in the plant were similar to levels predicted from laboratory biochemical methane potential (BMP) testing. Model based analysis identified no significant difference in batch laboratory parameters vs pilot-scale continuous parameters, and no change in speed or extent of degradation. However the TPAD process did result in a degree of process intensification with a high level of solids destruction at an average treatment time of 21days. Results from the pilot plant show that an integrated process enabled resource recovery at 7.8GJ/dry tonne paunch, 1.8kgP/dry tonne paunch and 1.0kgN/dry tonne paunch. PMID:26965211

  3. Dissecting Leishmania infantum Energy Metabolism - A Systems Perspective.

    Directory of Open Access Journals (Sweden)

    Abhishek Subramanian

    Full Text Available Leishmania infantum, causative agent of visceral leishmaniasis in humans, illustrates a complex lifecycle pertaining to two extreme environments, namely, the gut of the sandfly vector and human macrophages. Leishmania is capable of dynamically adapting and tactically switching between these critically hostile situations. The possible metabolic routes ventured by the parasite to achieve this exceptional adaptation to its varying environments are still poorly understood. In this study, we present an extensively reconstructed energy metabolism network of Leishmania infantum as an attempt to identify certain strategic metabolic routes preferred by the parasite to optimize its survival in such dynamic environments. The reconstructed network consists of 142 genes encoding for enzymes performing 237 reactions distributed across five distinct model compartments. We annotated the subcellular locations of different enzymes and their reactions on the basis of strong literature evidence and sequence-based detection of cellular localization signal within a protein sequence. To explore the diverse features of parasite metabolism the metabolic network was implemented and analyzed as a constraint-based model. Using a systems-based approach, we also put forth an extensive set of lethal reaction knockouts; some of which were validated using published data on Leishmania species. Performing a robustness analysis, the model was rigorously validated and tested for the secretion of overflow metabolites specific to Leishmania under varying extracellular oxygen uptake rate. Further, the fate of important non-essential amino acids in L. infantum metabolism was investigated. Stage-specific scenarios of L. infantum energy metabolism were incorporated in the model and key metabolic differences were outlined. Analysis of the model revealed the essentiality of glucose uptake, succinate fermentation, glutamate biosynthesis and an active TCA cycle as driving forces for parasite

  4. An integrated approach to energy production and nutrient recovery through anaerobic digestion of Vetiveria zizanoides

    OpenAIRE

    Crocamo, Angelo; Di Berardino, Santino; Di Giovanni, Raffaele; FABBRICINO, Massimiliano; Martins-Dias, Susete

    2015-01-01

    This paper reports on experimental results used to verify the applicability of Vetiveria zizanoides (VZ) as a virtuous energetic crop. VZ produces biogas through its anaerobic digestion, and its nutrient content can be recovered through reuse, after digestion, as an agricultural amendment. Biomethanation tests were conducted with fresh and pretreated VZ, and the results of these tests were compared with those from the anaerobic degradation of common garden grass. Specific methane production w...

  5. Physiology of leptin: energy homeostasis, neuroendocrine function and metabolism

    OpenAIRE

    Park, Hyeong-Kyu; Ahima, Rexford S.

    2014-01-01

    Leptin is secreted by adipose tissue and regulates energy homeostasis, neuroendocrine function, metabolism, immune function and other systems through its effects on the central nervous system and peripheral tissues. Leptin administration has been shown to restore metabolic and neuroendocrine abnormalities in individuals with leptin-deficient states, including hypothalamic amenorrhea and lipoatrophy. In contrast, obese individuals are resistant to leptin. Recombinant leptin is beneficial in pa...

  6. Probing the redox metabolism in the strictly anaerobic, extremely thermophilic, hydrogen-producing Caldicellulosiruptor saccharolyticus using amperometry

    DEFF Research Database (Denmark)

    Kostesha, Natalie; Willquist, Karin; Emnéus, Jenny;

    2011-01-01

    flow between cells harvested in the exponential and stationary growth phases. The electron flow of C. saccharolyticus was dependent on the NADH- and reduced ferredoxin generation flux and the competitive behavior of cytosolic and membrane-associated oxidoreductases. Sodium oxamate was used to inhibit...... electron flow were observed when cells were supplied with different carbon sources. A higher electrochemical response was detected when cells were supplied with xylose than with sucrose or glucose. Moreover, using the mediated electrochemical method, it was possible to detect differences in the electron...... in the intracellular electron flow and to probe redox enzyme properties of a strictly anaerobic thermophile in vivo....

  7. Characterizing the anaerobic response of Chlamydomonas reinhardtii by quantitative proteomics.

    Science.gov (United States)

    Terashima, Mia; Specht, Michael; Naumann, Bianca; Hippler, Michael

    2010-07-01

    The versatile metabolism of the green alga Chlamydomonas reinhardtii is reflected in its complex response to anaerobic conditions. The anaerobic response is also remarkable in the context of renewable energy because C. reinhardtii is able to produce hydrogen under anaerobic conditions. To identify proteins involved during anaerobic acclimation as well as to localize proteins and pathways to the powerhouses of the cell, chloroplasts and mitochondria from C. reinhardtii in aerobic and anaerobic (induced by 8 h of argon bubbling) conditions were isolated and analyzed using comparative proteomics. A total of 2315 proteins were identified. Further analysis based on spectral counting clearly localized 606 of these proteins to the chloroplast, including many proteins of the fermentative metabolism. Comparative quantitative analyses were performed with the chloroplast-localized proteins using stable isotopic labeling of amino acids ([(13)C(6)]arginine/[(12)C(6)]arginine in an arginine auxotrophic strain). The quantitative data confirmed proteins previously characterized as induced at the transcript level as well as identified several new proteins of unknown function induced under anaerobic conditions. These proteins of unknown function provide new candidates for further investigation, which could bring insights for the engineering of hydrogen-producing alga strains. PMID:20190198

  8. ECO-ENERGY DEMONSTRATION MODEL: ANAEROBIC DIGESTION, ALGAE AND ENERGY PROSPERITY

    Science.gov (United States)

    For the project, we: Designed and constructed an ecological energy model system. Investigated and characterized locally abundant agricultural and domestic waste resources that can have significant environmental impacts (dairy manure, poultry m...

  9. Energy Metabolism Disorder as a Contributing Factor of Rheumatoid Arthritis: A Comparative Proteomic and Metabolomic Study.

    Directory of Open Access Journals (Sweden)

    Xin Yu Yang

    Full Text Available To explore the pathogenesis of rheumatoid arthritis (RA, the different metabolites were screened in synovial fluid by metabolomics.Synovial fluid from 25 RA patients and 10 normal subjects were analyzed by GC/TOF MS analysis so as to give a broad overview of synovial fluid metabolites. The metabolic profiles of RA patients and normal subjects were compared using multivariate statistical analysis. Different proteins were verified by qPCR and western blot. Different metabolites were verified by colorimetric assay kit in 25 inactive RA patients, 25 active RA patients and 20 normal subjects. The influence of hypoxia-inducible factor (HIF-1α pathway on catabolism was detected by HIF-1α knockdown.A subset of 58 metabolites was identified, in which the concentrations of 7 metabolites related to energy metabolism were significantly different as shown by importance in the projection (VIP (VIP ≥ 1 and Student's t-test (p<0.05. In the 7 metabolites, the concentration of glucose was decreased, and the concentration of lactic acid was increased in the synovial fluid of RA patients than normal subjects verified by colorimetric assay Kit. Receiver operator characteristic (ROC analysis shows that the concentration of glucose and lactic acid in synovial fluid could be used as dependable biomarkers for the diagnosis of active RA, provided an AUC of 0.906 and 0.922. Sensitivity and specificity, which were determined by cut-off points, reached 84% and 96% in sensitivity and 95% and 85% in specificity, respectively. The verification of different proteins identified in our previous proteomic study shows that the enzymes of anaerobic catabolism were up-regulated (PFKP and LDHA, and the enzymes of aerobic oxidation and fatty acid oxidation were down-regulated (CS, DLST, PGD, ACSL4, ACADVL and HADHA in RA patients. The expression of HIF-1α and the enzymes of aerobic oxidation and fatty acid oxidation were decreased and the enzymes of anaerobic catabolism were

  10. My Lifelong Passion for Biochemistry and Anaerobic Microorganisms.

    Science.gov (United States)

    Thauer, Rudolf Kurt

    2015-01-01

    Early parental influence led me first to medical school, but after developing a passion for biochemistry and sensing the need for a deeper foundation, I changed to chemistry. During breaks between semesters, I worked in various biochemistry labs to acquire a feeling for the different areas of investigation. The scientific puzzle that fascinated me most was the metabolism of the anaerobic bacterium Clostridium kluyveri, which I took on in 1965 in Karl Decker's lab in Freiburg, Germany. I quickly realized that little was known about the biochemistry of strict anaerobes such as clostridia, methanogens, acetogens, and sulfate-reducing bacteria and that these were ideal model organisms to study fundamental questions of energy conservation, CO2 fixation, and the evolution of metabolic pathways. My passion for anaerobes was born then and is unabated even after 50 years of study.

  11. Flexibility in Anaerobic Metabolism as Revealed in a Mutant of Chlamydomonas reinhardtii Lacking Hydrogenase Activity*S⃞

    OpenAIRE

    Dubini, Alexandra; Mus, Florence; Seibert, Michael; Grossman, Arthur R.; Posewitz, Matthew C.

    2009-01-01

    The green alga Chlamydomonas reinhardtii has a network of fermentation pathways that become active when cells acclimate to anoxia. Hydrogenase activity is an important component of this metabolism, and we have compared metabolic and regulatory responses that accompany anaerobiosis in wild-type C. reinhardtii cells and a null mutant strain for the HYDEF gene (hydEF-1 mutant), which encodes an [FeFe] hydrogenase maturation protein. This mutant has no hydrogenase activity...

  12. Anaerobic phosphate release from activated sludge with enhanced biological phosphorus removal. A possible mechanism of intracellular pH control

    Energy Technology Data Exchange (ETDEWEB)

    Bond, P.L.; Keller, J.; Blackall, L.L. [Univ. of Queensland, Brisbane (Australia)

    1999-06-05

    The biochemical mechanisms of the wastewater treatment process known as enhanced biological phosphorus removal (EBPR) are presently described in a metabolic model. The authors investigated details of the EBPR model to determine the nature of the anaerobic phosphate release and how this may be metabolically associated with polyhydroxyalkanoate (PHA) formation. Iodoacetate, an inhibitor of glycolysis, was found to inhibit the anaerobic formation of PHA and phosphate release, supporting the pathways proposed in the EBPR metabolic model. In the metabolic model, it is proposed that polyphosphate degradation provides energy for the microorganisms in anaerobic regions of these treatment systems. Other investigations have shown that anaerobic phosphate release depends on the extracellular pH. The authors observed that when the intracellular pH of EBPR sludge was raised, substantial anaerobic phosphate release was caused without volatile fatty acid (VFA) uptake. Acidification of the sludge inhibited anaerobic phosphate release even in the presence of VFA. from these observations, the authors postulate that an additional possible role of anaerobic polyphosphate degradation in EBPR is for intracellular pH control. Intracellular pH control may be a metabolic feature of EBPR, not previously considered, that could have some use in the control and optimization of EBPR.

  13. Metabolic shift and electron discharge pattern of anaerobic consortia as a function of pretreatment method applied during fermentative hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Srikanth, S.; Venkata Mohan, S.; Lalit Babu, V.; Sarma, P.N. [Bioengineering and Environmental Centre, Indian Institute of Chemical Technology, Hyderabad 500 607, AP (India)

    2010-10-15

    We have made an attempt to evaluate the variation in the electron discharge (ED) pattern of anaerobic consortia as a function of pretreatment viz., chemical, heat-shock, acid and oxygen-shock in comparison with untreated mixed consortia during fermentative hydrogen (H{sub 2}) production. Experiments were performed with dairy wastewater as substrate using anaerobic mixed consortia as biocatalyst (pretreated individually and in combination). Cyclic voltammetry (CV) elucidated significant variation in the ED pattern of mixed consortia along with H{sub 2} production and substrate degradation (SD) as a function of pretreatment method applied. Higher ED was observed with all pretreated consortia which can be attributed to the stable proton (H{sup +}) shuttling due to the suppression of methanogenic activity. Oxygen-shock method and untreated consortia showed lower H{sub 2} production and higher SD among the variations studied, while, combined pretreated consortia resulted higher H{sub 2} production and lower SD. Lower ED observed with untreated consortia suggests the H{sup +} reduction during methanogenesis rather than the inter-conversion of metabolites, which is presumed to be necessary for H{sub 2} production. ED observed with combined pretreated consortia corroborated well with the observed H{sub 2} production. Redox pairs were visualized on the voltammograms with almost all the experimental variations studied except untreated consortia. The potentials (E{sub 0}) of redox pairs observed were corresponding to intracellular electron carriers viz., NAD{sup +}/NADH (E{sub 0} -0.32 V) and FAD{sup +}/FADH{sub 2} (E{sub 0} -0.24 V). (author)

  14. Impact of sludge thickening on energy recovery from anaerobic digestion[Held jointly with the 4. Canadian organic residuals and biosolids managment conference

    Energy Technology Data Exchange (ETDEWEB)

    Puchajda, B. [Stantec Consulting Ltd., Winnipeg, MB (Canada); Oleszkiewicz, J. [Manitoba Univ., Winnipeg, MB (Canada). Dept. of Civil Engineering

    2007-07-01

    The anaerobic digestion of wastewater sludge leads to production of a biogas mixture of methane and carbon dioxide. The technology of anaerobic digestion has been applied in various configurations and generally claims greater biogas production and additional stability to the process as compared to conventional mesophilic anaerobic digestion. However, biogas production is only one of many components of anaerobic digester energy balance. This paper presented energy balances for various digestion systems, including single mesophilic digestion; single thermophilic digestion; two-stage thermophilic-mesophilic digestion; and systems at elevated solids content in sludge. Energy balance included two components, namely energy demand and recoverable energy. Energy demand is defined as energy required for process operation such as heat requirement to elevate sludge temperature, and heat losses through digesters walls. Recoverable energy is defined as energy associated with methane content in biogas, that can be recovered either in the form of heat or electricity, and heat recovered through heat exchangers. The paper identified the assumptions used in all energy balance calculations. It presented the objectives and methods of the study as well as the results. It was concluded that two-stage thermophilic-mesophilic digestion system generate more available energy than single mesophilic digestion and single thermophilic digestion systems. Sludge thickening offers the greatest amount of available energy. However, that energy surplus is offset by the cost of thickening. 12 refs., 3 tabs., 6 figs.

  15. Therapeutic Implications of Targeting Energy Metabolism in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Meena K. Sakharkar

    2013-01-01

    Full Text Available PPARs are ligand activated transcription factors. PPARγ agonists have been reported as a new and potentially efficacious treatment of inflammation, diabetes, obesity, cancer, AD, and schizophrenia. Since cancer cells show dysregulation of glycolysis they are potentially manageable through changes in metabolic environment. Interestingly, several of the genes involved in maintaining the metabolic environment and the central energy generation pathway are regulated or predicted to be regulated by PPARγ. The use of synthetic PPARγ ligands as drugs and their recent withdrawal/restricted usage highlight the lack of understanding of the molecular basis of these drugs, their off-target effects, and their network. These data further underscores the complexity of nuclear receptor signalling mechanisms. This paper will discuss the function and role of PPARγ in energy metabolism and cancer biology in general and its emergence as a promising therapeutic target in breast cancer.

  16. Anaerobic Digestion and Biogas Production: Combine Effluent Treatment with Energy Generation in UASB Reactor as Biorefinery Annex

    Directory of Open Access Journals (Sweden)

    Mauro Berni

    2014-01-01

    Full Text Available The issue of residues and industrial effluents represents an unprecedented environmental challenge in terms of recovery, storage, and treatment. This work discusses the perspectives of treating effluents through anaerobic digestion as well as reporting the experience of using an upflow anaerobic sludge blanket (UASB reactor as biorefinery annex in a pulp and paper industrial plant to be burned in the boilers. The performance of the reactors has shown to be stable under considerable variations in load and showed a significant potential in terms of biogas production. The reactors UASB treated 3600.00 m3 of effluent daily from a production of 150.00 tons. The biogas generation was 234.000 kg/year/mill, equivalent in combustible oil. The results of methane gas generated by the anaerobic system UASB (8846.00 kcal/m3 dislocate the equivalent of 650.0 kg of combustible oil (10000.00 kcal/kg per day (or 234.000 kg/year. The production of 8846.00 Kcal/m3 of energy from biogas can make a run at industrial plant for 2 hours. This substitution can save US$ 128.700 annually (or US$ 550.0 of fuel oil/tons. The companies are invested in the use of the biogas in diesel stationary motors cycle that feed the boilers with water in case of storage electricity.

  17. THE GENERATION OF METABOLIC ENERGY BY SOLUTE TRANSPORT

    NARCIS (Netherlands)

    Konings, W.N; Lolkema, J.S.; Poolman, B.

    1995-01-01

    Secondary metabolic-energy-generating systems generate a proton motive force (pmf) or a sodium ion motive force (smf) by a process that involves the action of secondary transporters. The (electro)chemical gradient of the solute(s) is converted into the electrochemical gradient of protons or sodium i

  18. Fatty Acids in Energy Metabolism of the Central Nervous System

    Directory of Open Access Journals (Sweden)

    Alexander Panov

    2014-01-01

    Full Text Available In this review, we analyze the current hypotheses regarding energy metabolism in the neurons and astroglia. Recently, it was shown that up to 20% of the total brain’s energy is provided by mitochondrial oxidation of fatty acids. However, the existing hypotheses consider glucose, or its derivative lactate, as the only main energy substrate for the brain. Astroglia metabolically supports the neurons by providing lactate as a substrate for neuronal mitochondria. In addition, a significant amount of neuromediators, glutamate and GABA, is transported into neurons and also serves as substrates for mitochondria. Thus, neuronal mitochondria may simultaneously oxidize several substrates. Astrocytes have to replenish the pool of neuromediators by synthesis de novo, which requires large amounts of energy. In this review, we made an attempt to reconcile β-oxidation of fatty acids by astrocytic mitochondria with the existing hypothesis on regulation of aerobic glycolysis. We suggest that, under condition of neuronal excitation, both metabolic pathways may exist simultaneously. We provide experimental evidence that isolated neuronal mitochondria may oxidize palmitoyl carnitine in the presence of other mitochondrial substrates. We also suggest that variations in the brain mitochondrial metabolic phenotype may be associated with different mtDNA haplogroups.

  19. Recovery of energy from Taro (Colocasia esculenta) with solid-feed anaerobic digesters (SOFADs).

    Science.gov (United States)

    Bindu, T; Ramasamy, E V

    2008-01-01

    We present studies on solid-feed anaerobic digesters (SOFADs) in which chopped Colocasia esculenta was fed without any other pretreatment, in an attempt to develop an efficient means of utilizing the semi-aquatic weed that is otherwise an environmental nuisance. Two types of SOFADs were studied. The first type had a single vessel with two compartments. The lower portion of the digester, 25% of the total volume, was separated from the upper by a perforated PVC disk. The weed was charged from the top and inoculated with anaerobically digested cow dung-water slurry. The fermentation of the weed in the digester led to the formation of volatile fatty acids (VFAs) plus some biogas. The bioleachate, rich in the VFAs, passed through the perforated PVC disk and was collected in the lower compartment of the digester. The other type of digesters, referred to as anaerobic multi-phase high-solids digesters (AMHDs), had the same type of compartmentalized digester unit as the first type and an additional methaniser unit. Up-flow anaerobic filters (UAFs) were used as methaniser units, which converted the bioleachate into combustible biogas consisting of approximately 60% methane. All SOFADs developed a consistent performance in terms of biogas yield within 20 weeks from the start. Among the two types of digesters studied, the AMHDs were found to perform better with a twofold increase in biogas yield compared to the first type of digesters.

  20. Metabolism of reduced methylated sulfur compounds in anaerobic sediments and by a pure culture of an estuarine methanogen

    International Nuclear Information System (INIS)

    Addition of dimethylsulfide (DMS), dimethyldisulfide (DMDS), or methane thiol (MSH) to a diversity of anoxic aquatic sediments (e.g., fresh water, estuarine, alkaline/hypersaline) stimulated methane production. The yield of methane recovered from DMS was often 52 to 63%, although high concentrations of DMS (as well as MSH and DMDS) inhibited methanogenesis in some types of sediments. Production of methane from these reduced methylated sulfur compounds was blocked by 2-bromoethanesulfonic acid. Sulfate did not influence the metabolism of millimolar levels of DMS, DMDs, or MSH added to sediments. However, when DMS was added at ∼2-3=M levels as [14C]DMS, metabolism by sediments resulted in a 14CH4/14CO2 ratio of only 0.06. Addition of molybdate increased the ratio of 1.8, while 2-bromoethanesulfonic acid decreased it to 0, but did not block 14CO2 production. These results indicate the methanogens and sulfate reducers compete for DMS when it is present at low concentrations; however, at high concentrations, DMS is a noncompetitive substrate for methanogens. Metabolism of DMS by sediments resulted in the appearance of MSH as a transient intermediate. A pure culture of an obligately methylotrophic estuarine methanogen was isolated which was capable of growth on DMS. Metabolism of DMS by the culture also resulted in the transient appearance of MSH, but the organism could grow on neither MSH nor DMDS. The culture metabolized [14C]-DMS to yield a 14CH4/14CO2 ratio of ∼ 2.8

  1. Adipose tissue remodeling: its role in energy metabolism and metabolic disorders

    Directory of Open Access Journals (Sweden)

    Sung Sik eChoe

    2016-04-01

    Full Text Available The adipose tissue is a central metabolic organ in the regulation of whole-body energy homeostasis. The white adipose tissue (WAT functions as a key energy reservoir for other organs, whereas the brown adipose tissue (BAT accumulates lipids for cold-induced adaptive thermogenesis. Adipose tissues secret various hormones, cytokines, and metabolites (termed as adipokines that control systemic energy balance by regulating appetitive signals from the central nerve system as well as metabolic activity in peripheral tissues. In response to changes in the nutritional status, the adipose tissue undergoes dynamic remodeling, including quantitative and qualitative alterations in adipose tissue resident cells. A growing body of evidence indicates that adipose tissue remodeling in obesity is closely associated with adipose tissue function. Changes in the number and size of the adipocytes affect the microenvironment of expanded fat tissues, accompanied by alterations in adipokine secretion, adipocyte death, local hypoxia, and fatty acid fluxes. Concurrently, stromal vascular cells in the adipose tissue, including immune cells, are involved in numerous adaptive processes, such as dead adipocyte clearance, adipogenesis, and angiogenesis, all of which are dysregulated in obese adipose tissue remodeling. Chronic over-nutrition triggers uncontrolled inflammatory responses, leading to systemic low-grade inflammation and metabolic disorders, such as insulin resistance. This review will discuss current mechanistic understandings of adipose tissue remodeling processes in adaptive energy homeostasis and pathological remodeling of adipose tissue in connection with immune response.

  2. Adipose Tissue Remodeling: Its Role in Energy Metabolism and Metabolic Disorders.

    Science.gov (United States)

    Choe, Sung Sik; Huh, Jin Young; Hwang, In Jae; Kim, Jong In; Kim, Jae Bum

    2016-01-01

    The adipose tissue is a central metabolic organ in the regulation of whole-body energy homeostasis. The white adipose tissue functions as a key energy reservoir for other organs, whereas the brown adipose tissue accumulates lipids for cold-induced adaptive thermogenesis. Adipose tissues secrete various hormones, cytokines, and metabolites (termed as adipokines) that control systemic energy balance by regulating appetitive signals from the central nerve system as well as metabolic activity in peripheral tissues. In response to changes in the nutritional status, the adipose tissue undergoes dynamic remodeling, including quantitative and qualitative alterations in adipose tissue-resident cells. A growing body of evidence indicates that adipose tissue remodeling in obesity is closely associated with adipose tissue function. Changes in the number and size of the adipocytes affect the microenvironment of expanded fat tissues, accompanied by alterations in adipokine secretion, adipocyte death, local hypoxia, and fatty acid fluxes. Concurrently, stromal vascular cells in the adipose tissue, including immune cells, are involved in numerous adaptive processes, such as dead adipocyte clearance, adipogenesis, and angiogenesis, all of which are dysregulated in obese adipose tissue remodeling. Chronic overnutrition triggers uncontrolled inflammatory responses, leading to systemic low-grade inflammation and metabolic disorders, such as insulin resistance. This review will discuss current mechanistic understandings of adipose tissue remodeling processes in adaptive energy homeostasis and pathological remodeling of adipose tissue in connection with immune response. PMID:27148161

  3. Adipose Tissue Remodeling: Its Role in Energy Metabolism and Metabolic Disorders.

    Science.gov (United States)

    Choe, Sung Sik; Huh, Jin Young; Hwang, In Jae; Kim, Jong In; Kim, Jae Bum

    2016-01-01

    The adipose tissue is a central metabolic organ in the regulation of whole-body energy homeostasis. The white adipose tissue functions as a key energy reservoir for other organs, whereas the brown adipose tissue accumulates lipids for cold-induced adaptive thermogenesis. Adipose tissues secrete various hormones, cytokines, and metabolites (termed as adipokines) that control systemic energy balance by regulating appetitive signals from the central nerve system as well as metabolic activity in peripheral tissues. In response to changes in the nutritional status, the adipose tissue undergoes dynamic remodeling, including quantitative and qualitative alterations in adipose tissue-resident cells. A growing body of evidence indicates that adipose tissue remodeling in obesity is closely associated with adipose tissue function. Changes in the number and size of the adipocytes affect the microenvironment of expanded fat tissues, accompanied by alterations in adipokine secretion, adipocyte death, local hypoxia, and fatty acid fluxes. Concurrently, stromal vascular cells in the adipose tissue, including immune cells, are involved in numerous adaptive processes, such as dead adipocyte clearance, adipogenesis, and angiogenesis, all of which are dysregulated in obese adipose tissue remodeling. Chronic overnutrition triggers uncontrolled inflammatory responses, leading to systemic low-grade inflammation and metabolic disorders, such as insulin resistance. This review will discuss current mechanistic understandings of adipose tissue remodeling processes in adaptive energy homeostasis and pathological remodeling of adipose tissue in connection with immune response.

  4. PGC-1 coactivators in the control of energy metabolism

    Institute of Scientific and Technical Information of China (English)

    Chang Liu; Jiandie D.Lin

    2011-01-01

    Chronic disruption of energy balance, where energy intake exceeds expenditure, is a major risk factor for the development of metabolic syndrome. The latter is characterized by a constellation of symptoms including obesity, dyslipidemia, insulin resistance, hypertension, and nonalcoholic fatty liver disease. Altered expression of genes involved in glucose and lipid metabolism as well as mitochondrial oxidative phosphorylation has been implicated in the pathogenesis of these disorders. The peroxisome proliferator-activated receptor γ coactivator-1 (PGC-1) family of transcriptional coactivators is emerging as a hub linking nutritional and hormonal signals and energy metabolism. PGC-1а and PGC-1β are highly responsive to environmental cues and coordinate metabolic gene pro- grams through interaction with transcription factors and chromatin-remodeling proteins. PGC-1а has been implicated in the pathogenic conditions including obesity, type 2 diabetes, neurodegeneration, and cardiomyopathy, whereas PGC-1β plays an important role in plasma iipoprotein homeostasis and serves as a hepatic target for niacin, a potent hypotriglyceridemic drug. Here, we review recent advances in the identification of physiological and pathophysiological contexts involving PGC-1 coactivators, and also discuss their implications for therapeutic development.

  5. Anaerobic treatment as a core technology for energy, nutrients and water recovery from source-separated domestic waste(water).

    Science.gov (United States)

    Zeeman, Grietje; Kujawa, Katarzyna; de Mes, Titia; Hernandez, Lucia; de Graaff, Marthe; Abu-Ghunmi, Lina; Mels, Adriaan; Meulman, Brendo; Temmink, Hardy; Buisman, Cees; van Lier, Jules; Lettinga, Gatze

    2008-01-01

    Based on results of pilot scale research with source-separated black water (BW) and grey water (GW), a new sanitation concept is proposed. BW and GW are both treated in a UASB (-septic tank) for recovery of CH4 gas. Kitchen waste is added to the anaerobic BW treatment for doubling the biogas production. Post-treatment of the effluent is providing recovery of phosphorus and removal of remaining COD and nitrogen. The total energy saving of the new sanitation concept amounts to 200 MJ/year in comparison with conventional sanitation, moreover 0.14 kg P/p/year and 90 litres of potential reusable water are produced.

  6. Studies on growth, nitrogen and energy metabolism in rats

    DEFF Research Database (Denmark)

    Thorbek, G; Chwalibog, André; Eggum, B O;

    1982-01-01

    live weight the energy intake decreased from about 1400 to 800 kJ GE/kg0.75. With the high intake of energy the growth curve obtained is assumed to be near maximum level. The curve can be transformed to a linear one based on log days expressed as y, LW, g = -836 + 594 X log days with CV = 7.5% and r2......Feed intake, growth, nitrogen retention and energy metabolism were measured in 12 male Wistar rats fed ad lib. for 14 weeks with non-purified diets. The feed intake increased rapidly in 4 weeks time from 16 g/d to 25 g/d, and then it was constant in the following 10 weeks. In relation to metabolic...

  7. Performance evaluation of an anaerobic/aerobic landfill-based digester using yard waste for energy and compost production

    International Nuclear Information System (INIS)

    Highlights: ► Biochemical methane potential decreased by 83% during the two-stage operation. ► Net energy produced was 84.3 MWh or 46 kWh per million metric tons (Mg). ► The average removal efficiency of volatile organic compounds (VOCs) was 96–99%. ► The average removal efficiency of non-methane organic compounds (NMOCs) was 68–99%. ► The two-stage batch digester proved to be simple to operate and cost-effective. - Abstract: The objective of this study was to evaluate a new alternative for yard waste management by constructing, operating and monitoring a landfill-based two-stage batch digester (anaerobic/aerobic) with the recovery of energy and compost. The system was initially operated under anaerobic conditions for 366 days, after which the yard waste was aerated for an additional 191 days. Off gas generated from the aerobic stage was treated by biofilters. Net energy recovery was 84.3 MWh, or 46 kWh per million metric tons of wet waste (as received), and the biochemical methane potential of the treated waste decreased by 83% during the two-stage operation. The average removal efficiencies of volatile organic compounds and non-methane organic compounds in the biofilters were 96–99% and 68–99%, respectively.

  8. Mesophilic and thermophilic anaerobic digestion of the liquid fraction of pressed biowaste for high energy yields recovery.

    Science.gov (United States)

    Micolucci, Federico; Gottardo, Marco; Cavinato, Cristina; Pavan, Paolo; Bolzonella, David

    2016-02-01

    Deep separate collection of the organic fraction of municipal solid waste generates streams with relatively low content of inert material and high biodegradability. This material can be conveniently treated to recovery both energy and material by means of simplified technologies like screw-press and extruder: in this study, the liquid fraction generated from pressed biowaste from kerbside and door-to-door collection was anaerobically digested in both mesophilic and thermophilic conditions while for the solid fraction composting is suggested. Continuous operation results obtained both in mesophilic and thermophilic conditions indicated that the anaerobic digestion of pressed biowaste was viable at all operating conditions tested, with the greatest specific gas production of 0.92m(3)/kgVSfed at an organic loading rate of 4.7kgVS/m(3)d in thermophilic conditions. Based on calculations the authors found that the expected energy recovery is highly positive. The contents of heavy metals and pathogens of fed substrate and effluent digestates were analyzed, and results showed low levels (below End-of-Waste 2014 criteria limits) for both the parameters thus indicating the good quality of digestate and its possible use for agronomic purposes. Therefore, both energy and material were effectively recovered. PMID:26427935

  9. PPARs Integrate the Mammalian Clock and Energy Metabolism

    Directory of Open Access Journals (Sweden)

    Lihong Chen

    2014-01-01

    Full Text Available Peroxisome proliferator-activated receptors (PPARs are a group of nuclear receptors that function as transcription factors regulating the expression of numerous target genes. PPARs play an essential role in various physiological and pathological processes, especially in energy metabolism. It has long been known that metabolism and circadian clocks are tightly intertwined. However, the mechanism of how they influence each other is not fully understood. Recently, all three PPAR isoforms were found to be rhythmically expressed in given mouse tissues. Among them, PPARα and PPARγ are direct regulators of core clock components, Bmal1 and Rev-erbα, and, conversely, PPARα is also a direct Bmal1 target gene. More importantly, recent studies using knockout mice revealed that all PPARs exert given functions in a circadian manner. These findings demonstrated a novel role of PPARs as regulators in correlating circadian rhythm and metabolism. In this review, we summarize advances in our understanding of PPARs in circadian regulation.

  10. Anaerobic Treatment of Municipal Solid Waste and Sludge for Energy Production and Recycling of Nutrients

    Science.gov (United States)

    Leinonen, S.

    This volume contains 18 papers presented at a Nordic workshop dealing with application of anaerobic decomposition processes on various types of organic wastes, held at the Siikasalmi Research and Experimental Station of the University of Joensuu on 1-2 Oct. 1992. Subject coverage of the presentations extends from the biochemical and microbiological principles of organic waste processing to descriptions and practical experiences of various types of treatment plants. The theoretical and experimental papers include studies on anaerobic and thermophilic degradation processes, methanogenesis, effects of hydrogen, treatment of chlorinated and phenolic compounds, and process modeling, while the practical examples range from treatment of various types of municipal, industrial, and mining wastes to agricultural and fish farm effluents. The papers provide technical descriptions of several biogas plants in operation. Geographically, the presentations span the Nordic and Baltic countries.

  11. Status anaerobic energy sprinters qualified for the effects of a means of rehabilitation

    Directory of Open Access Journals (Sweden)

    Andriy Yefremenko

    2014-07-01

    Full Text Available Purpose: we determined the effect of the complex on the functional recovery of the state and dynamics of special physical qualities sprinters. Material and methods: the study involved 15 trained sprinters. Power anaerobic muscular activity was assessed using the battery of tests known. We have determined the ability of muscles, which reflects the potential for the rapid mobilization of productive resources systems sprinters. Results: dynamics of the special physical readiness test for the autumn-winter preparation period was positive and was at a high level, which was the key to improving athletic performance in a group of runners, sprinters, which was tested. Conclusions: revealed that the proposed complex of recovery has led to the growth rates of the special physical preparedness and capacity anaerobic power.

  12. Leptin regulates energy metabolism in MCF-7 breast cancer cells.

    Science.gov (United States)

    Blanquer-Rosselló, Maria del Mar; Oliver, Jordi; Sastre-Serra, Jorge; Valle, Adamo; Roca, Pilar

    2016-03-01

    Obesity is known to be a poorer prognosis factor for breast cancer in postmenopausal women. Among the diverse endocrine factors associated to obesity, leptin has received special attention since it promotes breast cancer cell growth and invasiveness, processes which force cells to adapt their metabolism to satisfy the increased demands of energy and biosynthetic intermediates. Taking this into account, our aim was to explore the effects of leptin in the metabolism of MCF-7 breast cancer cells. Polarographic analysis revealed that leptin increased oxygen consumption rate and cellular ATP levels were more dependent on mitochondrial oxidative metabolism in leptin-treated cells compared to the more glycolytic control cells. Experiments with selective inhibitors of glycolysis (2-DG), fatty acid oxidation (etomoxir) or aminoacid deprivation showed that ATP levels were more reliant on fatty acid oxidation. In agreement, levels of key proteins involved in lipid catabolism (FAT/CD36, CPT1, PPARα) and phosphorylation of the energy sensor AMPK were increased by leptin. Regarding glucose, cellular uptake was not affected by leptin, but lactate release was deeply repressed. Analysis of pyruvate dehydrogenase (PDH), lactate dehydrogenase (LDH) and pyruvate carboxylase (PC) together with the pentose-phosphate pathway enzyme glucose-6 phosphate dehydrogenase (G6PDH) revealed that leptin favors the use of glucose for biosynthesis. These results point towards a role of leptin in metabolic reprogramming, consisting of an enhanced use of glucose for biosynthesis and lipids for energy production. This metabolic adaptations induced by leptin may provide benefits for MCF-7 growth and give support to the reverse Warburg effect described in breast cancer. PMID:26772821

  13. Mechanistic modeling of aberrant energy metabolism in human disease

    Directory of Open Access Journals (Sweden)

    Vineet eSangar

    2012-10-01

    Full Text Available Dysfunction in energy metabolism—including in pathways localized to the mitochondria—has been implicated in the pathogenesis of a wide array of disorders, ranging from cancer to neurodegenerative diseases to type II diabetes. The inherent complexities of energy and mitochondrial metabolism present a significant obstacle in the effort to understand the role that these molecular processes play in the development of disease. To help unravel these complexities, systems biology methods have been applied to develop an array of computational metabolic models, ranging from mitochondria-specific processes to genome-scale cellular networks. These constraint-based models can efficiently simulate aspects of normal and aberrant metabolism in various genetic and environmental conditions. Development of these models leverages—and also provides a powerful means to integrate and interpret—information from a wide range of sources including genomics, proteomics, metabolomics, and enzyme kinetics. Here, we review a variety of mechanistic modeling studies that explore metabolic functions, deficiency disorders, and aberrant biochemical pathways in mitochondria and related regions in the cell.

  14. STAT3 Activities and Energy Metabolism: Dangerous Liaisons

    Energy Technology Data Exchange (ETDEWEB)

    Camporeale, Annalisa, E-mail: annalisa.camporeale@unito.it [Molecular Biotechnology Center and Department of Molecular Biotechnology and Life Sciences, University of Turin, Via Nizza 52, Turin 10126 (Italy); Demaria, Marco [Buck Institute for Research on Aging, 8001 Redwood Blvd, Novato, CA 94945 (United States); Monteleone, Emanuele [Molecular Biotechnology Center and Department of Molecular Biotechnology and Life Sciences, University of Turin, Via Nizza 52, Turin 10126 (Italy); Giorgi, Carlotta [Department of Experimental and Diagnostic Medicine, Section of General Pathology, Laboratory for Technologies of Advances Therapies (LTTA), University of Ferrara, Via Fossato di Mortara 70, Ferrara 44121 (Italy); Wieckowski, Mariusz R. [Nencki Institute of Experimental Biology, Department of Biochemistry, Pasteur Str. 3, Warsaw 02-093 (Poland); Pinton, Paolo [Department of Experimental and Diagnostic Medicine, Section of General Pathology, Laboratory for Technologies of Advances Therapies (LTTA), University of Ferrara, Via Fossato di Mortara 70, Ferrara 44121 (Italy); Poli, Valeria, E-mail: annalisa.camporeale@unito.it [Molecular Biotechnology Center and Department of Molecular Biotechnology and Life Sciences, University of Turin, Via Nizza 52, Turin 10126 (Italy)

    2014-07-31

    STAT3 mediates cytokine and growth factor receptor signalling, becoming transcriptionally active upon tyrosine 705 phosphorylation (Y-P). Constitutively Y-P STAT3 is observed in many tumors that become addicted to its activity, and STAT3 transcriptional activation is required for tumor transformation downstream of several oncogenes. We have recently demonstrated that constitutively active STAT3 drives a metabolic switch towards aerobic glycolysis through the transcriptional induction of Hif-1α and the down-regulation of mitochondrial activity, in both MEF cells expressing constitutively active STAT3 (Stat3{sup C/C}) and STAT3-addicted tumor cells. This novel metabolic function is likely involved in mediating pre-oncogenic features in the primary Stat3{sup C/C} MEFs such as resistance to apoptosis and senescence and rapid proliferation. Moreover, it strongly contributes to the ability of primary Stat3{sup C/C} MEFs to undergo malignant transformation upon spontaneous immortalization, a feature that may explain the well known causative link between STAT3 constitutive activity and tumor transformation under chronic inflammatory conditions. Taken together with the recently uncovered role of STAT3 in regulating energy metabolism from within the mitochondrion when phosphorylated on Ser 727, these data place STAT3 at the center of a hub regulating energy metabolism under different conditions, in most cases promoting cell survival, proliferation and malignant transformation even though with distinct mechanisms.

  15. Genome-scale comparison and constraint-based metabolic reconstruction of the facultative anaerobic Fe(III-reducer Rhodoferax ferrireducens

    Directory of Open Access Journals (Sweden)

    Daugherty Sean

    2009-09-01

    Full Text Available Abstract Background Rhodoferax ferrireducens is a metabolically versatile, Fe(III-reducing, subsurface microorganism that is likely to play an important role in the carbon and metal cycles in the subsurface. It also has the unique ability to convert sugars to electricity, oxidizing the sugars to carbon dioxide with quantitative electron transfer to graphite electrodes in microbial fuel cells. In order to expand our limited knowledge about R. ferrireducens, the complete genome sequence of this organism was further annotated and then the physiology of R. ferrireducens was investigated with a constraint-based, genome-scale in silico metabolic model and laboratory studies. Results The iterative modeling and experimental approach unveiled exciting, previously unknown physiological features, including an expanded range of substrates that support growth, such as cellobiose and citrate, and provided additional insights into important features such as the stoichiometry of the electron transport chain and the ability to grow via fumarate dismutation. Further analysis explained why R. ferrireducens is unable to grow via photosynthesis or fermentation of sugars like other members of this genus and uncovered novel genes for benzoate metabolism. The genome also revealed that R. ferrireducens is well-adapted for growth in the subsurface because it appears to be capable of dealing with a number of environmental insults, including heavy metals, aromatic compounds, nutrient limitation and oxidative stress. Conclusion This study demonstrates that combining genome-scale modeling with the annotation of a new genome sequence can guide experimental studies and accelerate the understanding of the physiology of under-studied yet environmentally relevant microorganisms.

  16. Anaerobic n-Alkane Metabolism by a Sulfate-Reducing Bacterium, Desulfatibacillum aliphaticivorans Strain CV2803T

    OpenAIRE

    Cravo-Laureau, Cristiana; Grossi, Vincent; Raphel, Danielle; Matheron, Robert; Hirschler-Réa, Agnès

    2005-01-01

    The alkane-degrading, sulfate-reducing bacterium Desulfatibacillum aliphaticivorans strain CV2803T, recently isolated from marine sediments, was investigated for n-alkane metabolism. The total cellular fatty acids of this strain had predominantly odd numbers of carbon atoms (C odd) when the strain was grown on a C-odd alkane (pentadecane) and even numbers of carbon atoms (C even) when it was grown on a C-even alkane (hexadecane). Detailed analyses of those fatty acids by gas chromatography/ma...

  17. Adaptation to anaerobic metabolism in two mussel species, Mytilus edulis and Mytilus galloprovincialis, from the tidal zone at Arcachon Bay, France

    Science.gov (United States)

    de Vooys, C. G. N.

    Aspects of anaerobic metabolism were investigated in two sympatric mussel species, viz. Mytilus edulis and Mytilus galloprovincialis, living in the tidal zone in Arcachon Bay, France. Specific activities of pyruvate kinase (PK) and phosphoenolpyruvate kinase (PEP-CK) were remarkably similar in the two sympatric species and generally corresponded more closely to those observed in M. galloprovincialis in the Mediterranean than with M. edulis in the Dutch Wadden Sea. However, the values for the radio PK: PEP-CK for the two species in Arcachon Bay agreed with those of intertidal M. edulis from the Dutch Wadden Sea. Succinate accumulation during the first 24 h of anaerobicsis was about the same as in M. galloprovincialis in the Mediterranean, but decreased during the second 24 h, particularly in M. edulis, obviously due to propionate formation. Decrease in ATP concentrations in the tissues during anaerobiosis corresponded to that of intertidal M. edulis from the Dutch Wadden Sea. With the exception of specific activities of PK and PEP-CK, all properties investigated in both species were as expected in intertidal mussels.

  18. Energy production from agricultural residues: High methane yields in pilot-scale two-stage anaerobic digestion

    International Nuclear Information System (INIS)

    There is a large, unutilised energy potential in agricultural waste fractions. In this pilot-scale study, the efficiency of a simple two-stage anaerobic digestion process was investigated for stabilisation and biomethanation of solid potato waste and sugar beet leaves, both separately and in co-digestion. A good phase separation between hydrolysis/acidification and methanogenesis was achieved, as indicated by the high carbon dioxide production, high volatile fatty acid concentration and low pH in the acidogenic reactors. Digestion of the individual substrates gave gross energy yields of 2.1-3.4 kWh/kg VS in the form of methane. Co-digestion, however, gave up to 60% higher methane yield, indicating that co-digestion resulted in improved methane production due to the positive synergism established in the digestion liquor. The integrity of the methane filters (MFs) was maintained throughout the period of operation, producing biogas with 60-78% methane content. A stable effluent pH showed that the methanogenic reactors had good ability to withstand the variations in load and volatile fatty acid concentrations that occurred in the two-stage process. The results of this pilot-scale study show that the two-stage anaerobic digestion system is suitable for effective conversion of semi-solid agricultural residues as potato waste and sugar beet leaves

  19. Energy metabolism in Desulfovibrio vulgaris Hildenborough: insights from transcriptome analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Patricia M.; He, Qiang; Valente, Filipa M.A.; Xavier, Antonio V.; Zhou, Jizhong; Pereira, Ines A.C.; Louro, Ricardo O.

    2007-11-01

    Sulphate-reducing bacteria are important players in the global sulphur and carbon cycles, with considerable economical and ecological impact. However, the process of sulphate respiration is still incompletely understood. Several mechanisms of energy conservation have been proposed, but it is unclear how the different strategies contribute to the overall process. In order to obtain a deeper insight into the energy metabolism of sulphate-reducers whole-genome microarrays were used to compare the transcriptional response of Desulfovibrio vulgaris Hildenborough grown with hydrogen/sulphate, pyruvate/sulphate, pyruvate with limiting sulphate, and lactate/thiosulphate, relative to growth in lactate/sulphate. Growth with hydrogen/sulphate showed the largest number of differentially expressed genes and the largest changes in transcript levels. In this condition the most up-regulated energy metabolism genes were those coding for the periplasmic [NiFeSe]hydrogenase, followed by the Ech hydrogenase. The results also provide evidence for the involvement of formate cycling and the recently proposed ethanol pathway during growth in hydrogen. The pathway involving CO cycling is relevant during growth on lactate and pyruvate, but not during growth in hydrogen as the most down-regulated genes were those coding for the CO-induced hydrogenase. Growth on lactate/thiosulphate reveals a down-regulation of several energymetabolism genes similar to what was observed in the presence of nitrite. This study identifies the role of several proteins involved in the energy metabolism of D. vulgaris and highlights several novel genes related to this process, revealing a more complex bioenergetic metabolism than previously considered.

  20. Carbon and energy metabolism of atp mutants of Escherichia coli

    DEFF Research Database (Denmark)

    Jensen, Peter Ruhdal; Michelsen, Ole

    1992-01-01

    The membrane-bound H+-ATPase plays a key role in free-energy transduction of biological systems. We report how the carbon and energy metabolism of Escherichia coli changes in response to deletion of the atp operon that encodes this enzyme. Compared with the isogenic wild-type strain, the growth...... of reducing equivalents. We interpret these data as indicating that E. coli makes use of its ability to respire even if it cannot directly couple this ability to ATP synthesis; by respiring away excess reducing equivalents E. coli enhances substrate level ATP synthesis....

  1. Energy and Oxygen Metabolism Disorder During Septic Acute Kidney Injury

    Directory of Open Access Journals (Sweden)

    Rong-li Yang

    2014-08-01

    Full Text Available Background/Aims: Acute kidney injury (AKI during septic shock, which is one of the most common clinical syndromes in the intensive care unit (ICU, has a high mortality rate and poor prognosis, partly because of a poor understanding of the pathogenesis of renal dysfunction during septic shock. Although ischemic injury of the kidney has been reported to result from adenosine triphosphate (ATP depletion, increasing evidence has demonstrated that AKI occurs in the absence of renal hypoperfusion and even occurs during normal or increased renal blood flow (RBF; nevertheless, whether energy metabolism disorder is involved in septic AKI and whether it changes according to renal hemodynamics have not been established. Moreover, tubular cell apoptosis, which is closely related to ATP depletion, rather than necrosis, has been shown to be the major form of cell injury during AKI. Methods: We used canine endotoxin shock models to investigate the hemodynamics, renal energy metabolism, renal oxygen metabolism, and pathological changes during septic AKI and to explore the underlying mechanisms of septic AKI. Results: The present results revealed that the nicotinamide adenine dinucleotide (NAD+ pool and the ATP/adenosine diphosphate (ADP ratio were significantly decreased during the early phase of septic AKI, which is accompanied by a decreased renal oxygen extraction ratio (O2ER% and decreased renal oxygen consumption (VO2. Furthermore, significant apoptosis was observed following renal dysfunction. RBF and renal oxygen delivery were not significantly altered. Conclusion: These results suggest that imbalanced energy metabolism, rather than tubular cell apoptosis, may be the initiator of renal dysfunction during septic shock.

  2. Weight Management, Energy Metabolism, and Endocrine Hor¬mones- Review Article

    OpenAIRE

    Mostafavi, Seyed-Ali; Hosseini, Saeed

    2015-01-01

    Energy expenditure is determined by basal metabolic rate, physical activity, and Thermic Effect of Foods (TEF). Some endocrine hormones have role in basal metabolism and hence in human energy expenditure. And some foods pose more thermic effects on the total body energy expenditure and therefore can influence body weight. This review was performed to discuss factors which may affect body metabolism and body weight. Latest medical databases and nutrition and metabolism books were reviewed. We ...

  3. Polyphosphate - an ancient energy source and active metabolic regulator

    Directory of Open Access Journals (Sweden)

    Achbergerová Lucia

    2011-08-01

    Full Text Available Abstract There are a several molecules on Earth that effectively store energy within their covalent bonds, and one of these energy-rich molecules is polyphosphate. In microbial cells, polyphosphate granules are synthesised for both energy and phosphate storage and are degraded to produce nucleotide triphosphate or phosphate. Energy released from these energetic carriers is used by the cell for production of all vital molecules such as amino acids, nucleobases, sugars and lipids. Polyphosphate chains directly regulate some processes in the cell and are used as phosphate donors in gene regulation. These two processes, energetic metabolism and regulation, are orchestrated by polyphosphate kinases. Polyphosphate kinases (PPKs can currently be categorized into three groups (PPK1, PPK2 and PPK3 according their functionality; they can also be divided into three groups according their homology (EcPPK1, PaPPK2 and ScVTC. This review discusses historical information, similarities and differences, biochemical characteristics, roles in stress response regulation and possible applications in the biotechnology industry of these enzymes. At the end of the review, a hypothesis is discussed in view of synthetic biology applications that states polyphosphate and calcium-rich organelles have endosymbiotic origins from ancient protocells that metabolized polyphosphate.

  4. Energy recovery from the effluent of plants anaerobically digesting urban solid waste

    Science.gov (United States)

    1983-03-01

    The parameters of concentration, time, temperature, and pH to find optimum conditions for enzymatically converting unreacted cellulose in the effluent of an anaerobic digester to glucose for ultimate conversion to methane, and then to project the economics to a 100 tons per day plant was studied. The amount of cellulose hydrolysis for enzyme concentrations from 5 to 1000 CIU/gram of substrate using either filter paper or anaerobically digested municipal solid waste (MSW) reacted over periods of time of from 0 to 72 hours is illustrated. The feasibility of recycling enzymes by ultrafilter capture was studied and it is shown that the recovered enzyme is not denatured by any of several possible enzyme loss mechanisms chemical, physical, or biological. Although rather stable enzyme substrate complexes seem to be formed, various techniques permit a 55% enzyme recovery. Posttreatment of digested MSW by cellulase enzymes produces nearly a threefold increase in biomethanation. The value of the additional methane produced in the process is not sufficient to support the cost of enzymes.

  5. Legal pre-event nutritional supplements to assist energy metabolism.

    Science.gov (United States)

    Spriet, Lawrence L; Perry, Christopher G R; Talanian, Jason L

    2008-01-01

    Physical training and proper nutrition are paramount for success in sport. A key tissue is skeletal muscle, as the metabolic pathways that produce energy or ATP allow the muscles to complete the many activities critical to success in sport. The energy-producing pathways must rapidly respond to the need for ATP during sport and produce energy at a faster rate or for a longer duration through training and proper nutrition which should translate into improved performance in sport activities. There is also continual interest in the possibility that nutritional supplements could further improve muscle metabolism and the provision of energy during sport. Most legal sports supplements do not improve performance following oral ingestion. However, three legal supplements that have received significant attention over the years include creatine, carnitine and sodium bicarbonate. The ingestion of large amounts of creatine for 4-6 days increases skeletal muscle creatine and phosphocreatine contents. The majority of the experimental evidence suggests that creatine supplementation can improve short-term exercise performance, especially in sports that require repeated short-term sprints. It may also augment the accretion of skeletal muscle when taken in combination with a resistance-exercise training programme. Supplementary carnitine has been touted to increase the uptake and oxidation of fat in the mitochondria. However, muscle carnitine levels are not augmented following oral carnitine supplementation and the majority of well-controlled studies have reported no effect of carnitine on enhancing fat oxidation, Vo(2max) or prolonged endurance exercise performance. The ingestion of sodium bicarbonate before intense exercise decreases the blood [H+] to potentially assist the efflux of H+ from the muscle and temper the metabolic acidosis associated with intense exercise. Many studies have reported performance increases in laboratory-based cycling tests and simulated running races in

  6. The use of cobs, a by-product of maize grain, for energy production in anaerobic digestion

    Directory of Open Access Journals (Sweden)

    Massimo Blandino

    2016-08-01

    Full Text Available Owing to the rising energy demand and the conflict between food, feed and energy crops for agricultural land, there is a growing need for alternative biomasses for energy purposes. New developments in harvesting technology have created the possibility of harvesting cobs as a by-product of maize grain harvesting. The aim of the present work has been to evaluate the potential and limitations of maize cob utilisation in an anaerobic digestion chain, considering the main agronomic, productive and qualitative traits. Maize grain and cob yields as well as the moisture content of samples collected from 1044 (farm fields (located in North West Italy have been determined over the 2012 growing season. Moreover, 27 representative fields were harvested using a modified combine-harvester that is able to collect maize grains and threshed cobs separately. The chemical composition and biochemical methane potential (BMP of the cobs have been analysed. The relative potential yield of maize cobs was established as 18.7% of the grain mass, while the wet cob yield recorded in the field after mechanical harvesting was 1.6 t ha–1. The total solid content was 60%. Fibre fractions represented over 85% of the dry cob matter, lignin content was about 16%, while the protein, ash, lipids and macro-elements (nitrogen, phosphorus, potassium contents were very low compared to the whole-plant maize used for silage. The average BMP of wet threshed cob was 250±20 Nm3 t VS–1. Collected data have underlined that maize cobs could be used as a sustainable feedstock for anaerobic digestion processes.

  7. Deletion of a gene cluster for [Ni-Fe] hydrogenase maturation in the anaerobic hyperthermophilic bacterium Caldicellulosiruptor bescii identifies its role in hydrogen metabolism.

    Science.gov (United States)

    Cha, Minseok; Chung, Daehwan; Westpheling, Janet

    2016-02-01

    The anaerobic, hyperthermophlic, cellulolytic bacterium Caldicellulosiruptor bescii grows optimally at ∼80 °C and effectively degrades plant biomass without conventional pretreatment. It utilizes a variety of carbohydrate carbon sources, including both C5 and C6 sugars, released from plant biomass and produces lactate, acetate, CO2, and H2 as primary fermentation products. The C. bescii genome encodes two hydrogenases, a bifurcating [Fe-Fe] hydrogenase and a [Ni-Fe] hydrogenase. The [Ni-Fe] hydrogenase is the most widely distributed in nature and is predicted to catalyze hydrogen production and to pump protons across the cellular membrane creating proton motive force. Hydrogenases are the key enzymes in hydrogen metabolism and their crystal structure reveals complexity in the organization of their prosthetic groups suggesting extensive maturation of the primary protein. Here, we report the deletion of a cluster of genes, hypABFCDE, required for maturation of the [Ni-Fe] hydrogenase. These proteins are specific for the hydrogenases they modify and are required for hydrogenase activity. The deletion strain grew more slowly than the wild type or the parent strain and produced slightly less hydrogen overall, but more hydrogen per mole of cellobiose. Acetate yield per mole of cellobiose was increased ∼67 % and ethanol yield per mole of cellobiose was decreased ∼39 %. These data suggest that the primary role of the [Ni-Fe] hydrogenase is to generate a proton gradient in the membrane driving ATP synthesis and is not the primary enzyme for hydrogen catalysis. In its absence, ATP is generated from increased acetate production resulting in more hydrogen produced per mole of cellobiose.

  8. Anaerobic Process.

    Science.gov (United States)

    Yang, Qian; Ju, Mei-Ting; Li, Wei-Zun; Liu, Le; Wang, Yan-Nan; Chang, Chein-Chi

    2016-10-01

    A review of the literature published in 2015 on the focus of Anaerobic Process. It is divided into the following sections. Pretreatment Organic waste Multiple-stage co-digestion Process Methodology and Technology. PMID:27620085

  9. Anaerobic bacteria

    Science.gov (United States)

    Brook I, Goldstein EJ. Diseases caused by non-spore forming anaerobic bacteria. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 297. Stedman's Online ...

  10. Metabolic evolution of energy-conserving pathways for succinate production in Escherichia coli

    OpenAIRE

    Zhang, Xueli; Jantama, Kaemwich; Moore, Jonathan C.; Jarboe, Laura R.; Shanmugam, Keelnatham T.; Lonnie O. Ingram

    2009-01-01

    During metabolic evolution to improve succinate production in Escherichia coli strains, significant changes in cellular metabolism were acquired that increased energy efficiency in two respects. The energy-conserving phosphoenolpyruvate (PEP) carboxykinase (pck), which normally functions in the reverse direction (gluconeogenesis; glucose repressed) during the oxidative metabolism of organic acids, evolved to become the major carboxylation pathway for succinate production. Both PCK enzyme acti...

  11. Comparing environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy – A life cycle perspective

    NARCIS (Netherlands)

    Vries, de J.W.; Vinken, T.M.W.J.; Hamelin, L.; Boer, de I.J.M.

    2012-01-01

    The aim of this work was to assess the environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy, from a life cycle perspective. This included assessing environmental impacts and land use change emissions (LUC) required to replace used co-substrates for anaer

  12. Energy- and CO2-reduction potentials by anaerobic treatment of wastewater and organic kitchen wastes in consideration of different climatic conditions.

    Science.gov (United States)

    Weichgrebe, D; Urban, I; Friedrich, K

    2008-01-01

    The classical municipal wastewater treatment in Germany consists of an aerobic carbon and nitrogen elimination and mostly an anaerobic sludge treatment. Organic kitchen wastes from separate waste collection as well as yard wastes are converted mostly in composting plants to soil conditioner. With these conventional types of treatment, the energy potential in waste and wastewater is lost due to aerobic material conversion. In this article three scenarios for the treatment of municipal wastewater and waste are compared on the subject of energy efficiency and useable potential: Sc1. the classical wastewater treatment and the composting of the organic waste fraction, Sc2. the anaerobic treatment of wastewater combined with deammonification and the digestion of the organic waste fraction, and Sc3. a mutual anaerobic treatment of wastewater and waste as co-digestion with deammonification. The calculation of energy and CO2-balance considers different climatic conditions. In case of using anaerobic treatment, not only the energy balance will be positive, also the CO2-balance is improved by the substitution of fossil fuels with generated biogas.

  13. Comparing environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy – A life cycle perspective

    DEFF Research Database (Denmark)

    De Vries, J.W.; Vinken, T.M.W.J; Hamelin, Lorie;

    2012-01-01

    The aim of this work was to assess the environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy, from a life cycle perspective. This included assessing environmental impacts and land use change emissions (LUC) required to replace used co-substrates for an...

  14. GIBBS FREE-ENERGY OF FORMATION OF HALOGENATED AROMATIC-COMPOUNDS AND THEIR POTENTIAL ROLE AS ELECTRON-ACCEPTORS IN ANAEROBIC ENVIRONMENTS

    NARCIS (Netherlands)

    DOLFING, J; HARRISON, BK

    1992-01-01

    The Gibbs free energies of formation of various classes of halogenated aromatic compounds were estimated with Benson's method. The data were used to evaluate the potential of these compounds to serve as electron acceptors in anaerobic environments. The results indicate that for (chloro) benzenes, be

  15. Experimental ocean acidification alters the allocation of metabolic energy.

    Science.gov (United States)

    Pan, T-C Francis; Applebaum, Scott L; Manahan, Donal T

    2015-04-14

    Energy is required to maintain physiological homeostasis in response to environmental change. Although responses to environmental stressors frequently are assumed to involve high metabolic costs, the biochemical bases of actual energy demands are rarely quantified. We studied the impact of a near-future scenario of ocean acidification [800 µatm partial pressure of CO2 (pCO2)] during the development and growth of an important model organism in developmental and environmental biology, the sea urchin Strongylocentrotus purpuratus. Size, metabolic rate, biochemical content, and gene expression were not different in larvae growing under control and seawater acidification treatments. Measurements limited to those levels of biological analysis did not reveal the biochemical mechanisms of response to ocean acidification that occurred at the cellular level. In vivo rates of protein synthesis and ion transport increased ∼50% under acidification. Importantly, the in vivo physiological increases in ion transport were not predicted from total enzyme activity or gene expression. Under acidification, the increased rates of protein synthesis and ion transport that were sustained in growing larvae collectively accounted for the majority of available ATP (84%). In contrast, embryos and prefeeding and unfed larvae in control treatments allocated on average only 40% of ATP to these same two processes. Understanding the biochemical strategies for accommodating increases in metabolic energy demand and their biological limitations can serve as a quantitative basis for assessing sublethal effects of global change. Variation in the ability to allocate ATP differentially among essential functions may be a key basis of resilience to ocean acidification and other compounding environmental stressors.

  16. Arsenic, Anaerobes, and Astrobiology

    Science.gov (United States)

    Stolz, J. F.; Oremland, R. S.; Switzer Blum, J.; Hoeft, S. E.; Baesman, S. M.; Bennett, S.; Miller, L. G.; Kulp, T. R.; Saltikov, C.

    2013-12-01

    Arsenic is an element best known for its highly poisonous nature, so it is not something one would associate with being a well-spring for life. Yet discoveries made over the past two decades have delineated that not only are some microbes resistant to arsenic, but that this element's primary redox states can be exploited to conserve energy and support prokaryotic growth ('arsenotrophy') in the absence of oxygen. Hence, arsenite [As(III)] can serve as an electron donor for chemo- or photo-autotrophy while arsenate [As(V)] will serve as an electron acceptor for chemo-heterotrophs and chemo-autotrophs. The phylogenetic diversity of these microbes is broad, encompassing many individual species from diverse taxonomic groups in the Domain Bacteria, with fewer representatives in the Domain Archaea. Speculation with regard to the evolutionary origins of the key functional genes in anaerobic arsenic transformations (arrA and arxA) and aerobic oxidation (aioB) has led to a disputation as to which gene and function is the most ancient and whether arsenic metabolism extended back into the Archaean. Regardless of its origin, robust arsenic metabolism has been documented in extreme environments that are rich in their arsenic content, such as hot springs and especially hypersaline soda lakes associated with volcanic regions. Searles Lake, CA is an extreme, salt-saturated end member where vigorous arsenic metabolism occurs, but there is no detectable sulfate-reduction or methanogenesis. The latter processes are too weak bio-energetically to survive as compared with arsenotrophy, and are also highly sensitive to the abundance of borate ions present in these locales. These observations have implications with respect to the search for microbial life elsewhere in the Solar System where volcanic-like processes have been operative. Hence, because of the likelihood of encountering dense brines in the regolith of Mars (formed by evapo-concentration) or beneath the ice layers of Europa

  17. Intestinal triacylglycerol synthesis in fat absorption and systemic energy metabolism.

    Science.gov (United States)

    Yen, Chi-Liang Eric; Nelson, David W; Yen, Mei-I

    2015-03-01

    The intestine plays a prominent role in the biosynthesis of triacylglycerol (triglyceride; TAG). Digested dietary TAG is repackaged in the intestine to form the hydrophobic core of chylomicrons, which deliver metabolic fuels, essential fatty acids, and other lipid-soluble nutrients to the peripheral tissues. By controlling the flux of dietary fat into the circulation, intestinal TAG synthesis can greatly impact systemic metabolism. Genes encoding many of the enzymes involved in TAG synthesis have been identified. Among TAG synthesis enzymes, acyl-CoA:monoacylglycerol acyltransferase 2 and acyl-CoA:diacylglycerol acyltransferase (DGAT)1 are highly expressed in the intestine. Their physiological functions have been examined in the context of whole organisms using genetically engineered mice and, in the case of DGAT1, specific inhibitors. An emerging theme from recent findings is that limiting the rate of TAG synthesis in the intestine can modulate gut hormone secretion, lipid metabolism, and systemic energy balance. The underlying mechanisms and their implications for humans are yet to be explored. Pharmacological inhibition of TAG hydrolysis in the intestinal lumen has been employed to combat obesity and associated disorders with modest efficacy and unwanted side effects. The therapeutic potential of inhibiting specific enzymes involved in intestinal TAG synthesis warrants further investigation.

  18. Intestinal triacylglycerol synthesis in fat absorption and systemic energy metabolism.

    Science.gov (United States)

    Yen, Chi-Liang Eric; Nelson, David W; Yen, Mei-I

    2015-03-01

    The intestine plays a prominent role in the biosynthesis of triacylglycerol (triglyceride; TAG). Digested dietary TAG is repackaged in the intestine to form the hydrophobic core of chylomicrons, which deliver metabolic fuels, essential fatty acids, and other lipid-soluble nutrients to the peripheral tissues. By controlling the flux of dietary fat into the circulation, intestinal TAG synthesis can greatly impact systemic metabolism. Genes encoding many of the enzymes involved in TAG synthesis have been identified. Among TAG synthesis enzymes, acyl-CoA:monoacylglycerol acyltransferase 2 and acyl-CoA:diacylglycerol acyltransferase (DGAT)1 are highly expressed in the intestine. Their physiological functions have been examined in the context of whole organisms using genetically engineered mice and, in the case of DGAT1, specific inhibitors. An emerging theme from recent findings is that limiting the rate of TAG synthesis in the intestine can modulate gut hormone secretion, lipid metabolism, and systemic energy balance. The underlying mechanisms and their implications for humans are yet to be explored. Pharmacological inhibition of TAG hydrolysis in the intestinal lumen has been employed to combat obesity and associated disorders with modest efficacy and unwanted side effects. The therapeutic potential of inhibiting specific enzymes involved in intestinal TAG synthesis warrants further investigation. PMID:25231105

  19. Ets-1 regulates energy metabolism in cancer cells.

    Directory of Open Access Journals (Sweden)

    Meghan L Verschoor

    Full Text Available Cancer cells predominantly utilize glycolysis for ATP production even in the presence of abundant oxygen, an environment that would normally result in energy production through oxidative phosphorylation. Although the molecular mechanism for this metabolic switch to aerobic glycolysis has not been fully elucidated, it is likely that mitochondrial damage to the electron transport chain and the resulting increased production of reactive oxygen species are significant driving forces. In this study, we have investigated the role of the transcription factor Ets-1 in the regulation of mitochondrial function and metabolism. Ets-1 was over-expressed using a stably-incorporated tetracycline-inducible expression vector in the ovarian cancer cell line 2008, which does not express detectable basal levels of Ets-1 protein. Microarray analysis of the effects of Ets-1 over-expression in these ovarian cancer cells shows that Ets-1 up-regulates key enzymes involved in glycolysis and associated feeder pathways, fatty acid metabolism, and antioxidant defense. In contrast, Ets-1 down-regulates genes involved in the citric acid cycle, electron transport chain, and mitochondrial proteins. At the functional level, we have found that Ets-1 expression is directly correlated with cellular oxygen consumption whereby increased expression causes decreased oxygen consumption. Ets-1 over-expression also caused increased sensitivity to glycolytic inhibitors, as well as growth inhibition in a glucose-depleted culture environment. Collectively our findings demonstrate that Ets-1 is involved in the regulation of cellular metabolism and response to oxidative stress in ovarian cancer cells.

  20. Metabolism

    Science.gov (United States)

    ... also influenced by body composition — people with more muscle and less fat generally have higher BMRs. previous continue Things That Can Go Wrong With Metabolism Most of the time your metabolism works effectively ...

  1. Combined anaerobic digestion and photocatalytic treatment of distillery effluent in fluidized bed reactors focusing on energy conservation.

    Science.gov (United States)

    Apollo, Seth; Aoyi, Ochieng

    2016-09-01

    Anaerobic digestion (AD) can remove substantial amount of organic load when applied in treating distillery effluent but it is ineffective in colour reduction. Conversely, photodegradation is effective in colour reduction but has high energy requirement. A study on the synergy of a combined AD and ultra violet (UV) photodegradation treatment of distillery effluent was carried out in fluidized bed reactors to evaluate pollution reduction and energy utilization efficiencies. The combined process improved colour removal from 41% to 85% compared to that of AD employed as a stand-alone process. An overall corresponding total organic carbon (TOC) reduction of 83% was achieved. The bioenergy production by the AD step was 14.2 kJ/g total organic carbon (TOC) biodegraded while UV lamp energy consumption was 0.9 kJ/mg TOC, corresponding to up to 100% colour removal. Electrical energy per order analysis for the photodegradation process showed that the bioenergy produced was 20% of that required by the UV lamp to photodegrade 1 m(3) of undiluted pre-AD treated effluent up to 75% colour reduction. It was concluded that a combined AD-UV system for treatment of distillery effluent is effective in organic load removal and can be operated at a reduced cost. PMID:26824301

  2. Metabolism

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008255 Serum adiponectin level declines in the elderly with metabolic syndrome.WU Xiaoyan(吴晓琰),et al.Dept Geriatr,Huashan Hosp,Fudan UnivShanghai200040.Chin J Geriatr2008;27(3):164-167.Objective To investigate the correlation between ser-um adiponectin level and metabolic syndrome in the elderly·Methods Sixty-one subjects with metabolic syndrome and140age matched subjects without metabolic

  3. On the kinetics of anaerobic power

    Directory of Open Access Journals (Sweden)

    Moxnes John F

    2012-07-01

    Full Text Available Abstract Background This study investigated two different mathematical models for the kinetics of anaerobic power. Model 1 assumes that the work power is linear with the work rate, while Model 2 assumes a linear relationship between the alactic anaerobic power and the rate of change of the aerobic power. In order to test these models, a cross country skier ran with poles on a treadmill at different exercise intensities. The aerobic power, based on the measured oxygen uptake, was used as input to the models, whereas the simulated blood lactate concentration was compared with experimental results. Thereafter, the metabolic rate from phosphocreatine break down was calculated theoretically. Finally, the models were used to compare phosphocreatine break down during continuous and interval exercises. Results Good similarity was found between experimental and simulated blood lactate concentration during steady state exercise intensities. The measured blood lactate concentrations were lower than simulated for intensities above the lactate threshold, but higher than simulated during recovery after high intensity exercise when the simulated lactate concentration was averaged over the whole lactate space. This fit was improved when the simulated lactate concentration was separated into two compartments; muscles + internal organs and blood. Model 2 gave a better behavior of alactic energy than Model 1 when compared against invasive measurements presented in the literature. During continuous exercise, Model 2 showed that the alactic energy storage decreased with time, whereas Model 1 showed a minimum value when steady state aerobic conditions were achieved. During interval exercise the two models showed similar patterns of alactic energy. Conclusions The current study provides useful insight on the kinetics of anaerobic power. Overall, our data indicate that blood lactate levels can be accurately modeled during steady state, and suggests a linear

  4. The anaerobic digestion process

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, C.J. [National Renewable Energy Lab., Golden, CO (United States); Boone, D.R. [Oregon Graduate Inst., Portland, OR (United States)

    1996-01-01

    The microbial process of converting organic matter into methane and carbon dioxide is so complex that anaerobic digesters have long been treated as {open_quotes}black boxes.{close_quotes} Research into this process during the past few decades has gradually unraveled this complexity, but many questions remain. The major biochemical reactions for forming methane by methanogens are largely understood, and evolutionary studies indicate that these microbes are as different from bacteria as they are from plants and animals. In anaerobic digesters, methanogens are at the terminus of a metabolic web, in which the reactions of myriads of other microbes produce a very limited range of compounds - mainly acetate, hydrogen, and formate - on which the methanogens grow and from which they form methane. {open_quotes}Interspecies hydrogen-transfer{close_quotes} and {open_quotes}interspecies formate-transfer{close_quotes} are major mechanisms by which methanogens obtain their substrates and by which volatile fatty acids are degraded. Present understanding of these reactions and other complex interactions among the bacteria involved in anaerobic digestion is only now to the point where anaerobic digesters need no longer be treated as black boxes.

  5. The SCFA receptor GPR43 and energy metabolism

    Directory of Open Access Journals (Sweden)

    Ikuo eKimura

    2014-06-01

    Full Text Available Free fatty acids (FFAs are essential nutrients and act as signaling molecules in various cellular processes via binding with FFA receptors. Of these receptors, GPR43 is activated by short chain fatty acids (SCFAs; e.g., acetate, propionate, and butyrate. During feeding, SCFAs are produced by microbial fermentation of dietary fiber in the gut, and these SCFAs become important energy sources for the host. The gut microbiota affects nutrient acquisition and energy regulation of the host and can influence the development of obesity, insulin resistance, and diabetes. Recently, GPR43 has been reported to regulate host energy homeostasis in the gastrointestinal tract and adipose tissues. Hence, GPR43 is also thought to be a potential drug target for metabolic disorders, such as obesity and diabetes. In this review, we summarize the identification, structure, and activities of GPR43, with a focus on host energy regulation, and present an essential overview of our current understanding of its physiological roles in host energy regulation that is mediated by gut microbiota. We also discuss the potential for GPR43 as a therapeutic target.

  6. Economic viability of anaerobic digestion

    Energy Technology Data Exchange (ETDEWEB)

    Wellinger, A. [INFOENERGIE, Ettenhausen (Switzerland)

    1996-01-01

    The industrial application of anaerobic digestion is a relatively new, yet proven waste treatment technology. Anaerobic digestion reduces and upgrades organic waste, and is a good way to control air pollution as it reduces methane and nitrous gas emissions. For environmental and energy considerations, anaerobic digestion is a nearly perfect waste treatment process. However, its economic viability is still in question. A number of parameters - type of waste (solid or liquid), digester system, facility size, product quality and end use, environmental requirements, cost of alternative treatments (including labor), and interest rates - define the investment and operating costs of an anaerobic digestion facility. Therefore, identical facilities that treat the same amount and type of waste may, depending on location, legislation, and end product characteristics, reveal radically different costs. A good approach for evaluating the economics of anaerobic digestion is to compare it to treatment techniques such as aeration or conventional sewage treatment (for industrial wastewater), or composting and incineration (for solid organic waste). For example, the cost (per ton of waste) of in-vessel composting with biofilters is somewhat higher than that of anaerobic digestion, but the investment costs 1 1/2 to 2 times more than either composting or anaerobic digestion. Two distinct advantages of anaerobic digestion are: (1) it requires less land than either composting or incinerating, which translates into lower costs and milder environmental and community impacts (especially in densely populated areas); and (2) it produces net energy, which can be used to operate the facility or sold to nearby industries.

  7. Investigation and analysis through modelling of the potential for renewable energy production and mitigation of greenhouse gas emissions from anaerobics digestion in Cyprus

    OpenAIRE

    Kythreotou, Nicoletta

    2014-01-01

    This thesis was submitted for the degree of Doctor of Philisophy and awarded by Brunel University Biodegradable wastes cause high emissions of greenhouse gases (GHG) if not properly treated. The emissions can be reduced by the development of an effective waste management strategy. Waste-to-energy technologies, such as anaerobic digestion (AD) can be utilised for this purpose. Biomass energy from wastes is of particular interest to Cyprus that has to meet legal commitments for reducing its ...

  8. Anaerobic wastewater treatment using anaerobic baffled bioreactor: a review

    Science.gov (United States)

    Hassan, Siti; Dahlan, Irvan

    2013-09-01

    Anaerobic wastewater treatment is receiving renewed interest because it offers a means to treat wastewater with lower energy investment. Because the microorganisms involved grow more slowly, such systems require clever design so that the microbes have sufficient time with the substrate to complete treatment without requiring enormous reactor volumes. The anaerobic baffled reactor has inherent advantages over single compartment reactors due to its circulation pattern that approaches a plug flow reactor. The physical configuration of the anaerobic baffled reactor enables significant modifications to be made; resulting in a reactor which is proficient of treating complex wastewaters which presently require only one unit, ultimately significant reducing capital costs. This paper also concerns about mechanism, kinetic and hydrodynamic studies of anaerobic digestion for future application of the anaerobic baffled reactor for wastewater treatment.

  9. Water-energy nexus: Anaerobic co-digestion with elephant grass hydrolyzate.

    Science.gov (United States)

    Carvalho, A R; Fragoso, R; Gominho, J; Saraiva, A; Costa, R; Duarte, E

    2016-10-01

    The anaerobic co-digestion process in a continuous stirred-tank reactor (CSTR) was carried out under mesophilic conditions (37 ± 0.2 °C). All the trials were performed at a hydraulic retention time (HRT) of 15 days and the AD reactor was daily fed with a mixture of sewage sludge (SS) and elephant grass hydrolyzate (EGH). In this study, three different trials were assessed, with different mixture proportions of SSSS and EGH: F0 (100:0,v/v), F1 (75:25, v/v) and F2 (50:50, v/v), during 90 days each trial, keeping the organic loading rate (OLR) in a range of 0.94-1.16 g VS L(-1) day(-1). The experimental results obtained showed that the soluble chemical oxygen demand (SCOD) removal efficiency was around 77% and 86% for trials F1 and F2, respectively. SS co-digestion with EGH enhanced methane yield, leading to an increment between 23% and 38%, in comparison with the reference scenario (F0).

  10. Modelling energy efficiency of an integrated anaerobic digestion and photodegradation of distillery effluent using response surface methodology.

    Science.gov (United States)

    Apollo, Seth; Onyango, Maurice S; Ochieng, Aoyi

    2016-10-01

    Anaerobic digestion (AD) is efficient in organic load removal and bioenergy recovery when applied in treating distillery effluent; however, it is ineffective in colour reduction. In contrast, ultraviolet (UV) photodegradation post-treatment for the AD-treated distillery effluent is effective in colour reduction but has high energy requirement. The effects of operating parameters on bioenergy production and energy demand of photodegradation were modelled using response surface methodology (RSM) with a view of developing a sustainable process in which the biological step could supply energy to the energy-intensive photodegradation step. The organic loading rate (OLRAD) and hydraulic retention time (HRTAD) of the initial biological step were the variables investigated. It was found that the initial biological step removed about 90% of COD and only about 50% colour while photodegradation post-treatment removed 98% of the remaining colour. Maximum bioenergy production of 180.5 kWh/m(3) was achieved. Energy demand of the UV lamp was lowest at low OLRAD irrespective of HRTAD, with values ranging between 87 and 496 kWh/m(3). The bioenergy produced formed 93% of the UV lamp energy demand when the system was operated at OLRAD of 3 kg COD/m(3) d and HRT of 20 days. The presumed carbon dioxide emission reduction when electricity from bioenergy was used to power the UV lamp was 28.8 kg CO2 e/m(3), which could reduce carbon emission by 31% compared to when electricity from the grid was used, leading to environmental conservation. PMID:26864148

  11. Modelling energy efficiency of an integrated anaerobic digestion and photodegradation of distillery effluent using response surface methodology.

    Science.gov (United States)

    Apollo, Seth; Onyango, Maurice S; Ochieng, Aoyi

    2016-10-01

    Anaerobic digestion (AD) is efficient in organic load removal and bioenergy recovery when applied in treating distillery effluent; however, it is ineffective in colour reduction. In contrast, ultraviolet (UV) photodegradation post-treatment for the AD-treated distillery effluent is effective in colour reduction but has high energy requirement. The effects of operating parameters on bioenergy production and energy demand of photodegradation were modelled using response surface methodology (RSM) with a view of developing a sustainable process in which the biological step could supply energy to the energy-intensive photodegradation step. The organic loading rate (OLRAD) and hydraulic retention time (HRTAD) of the initial biological step were the variables investigated. It was found that the initial biological step removed about 90% of COD and only about 50% colour while photodegradation post-treatment removed 98% of the remaining colour. Maximum bioenergy production of 180.5 kWh/m(3) was achieved. Energy demand of the UV lamp was lowest at low OLRAD irrespective of HRTAD, with values ranging between 87 and 496 kWh/m(3). The bioenergy produced formed 93% of the UV lamp energy demand when the system was operated at OLRAD of 3 kg COD/m(3) d and HRT of 20 days. The presumed carbon dioxide emission reduction when electricity from bioenergy was used to power the UV lamp was 28.8 kg CO2 e/m(3), which could reduce carbon emission by 31% compared to when electricity from the grid was used, leading to environmental conservation.

  12. Effects of ingesting JavaFit Energy Extreme functional coffee on aerobic and anaerobic fitness markers in recreationally-active coffee consumers.

    Science.gov (United States)

    Roberts, Michael D; Taylor, Lemuel W; Wismann, Jennifer A; Wilborn, Colin D; Kreider, Richard B; Willoughby, Darryn S

    2007-01-01

    The purpose of this study was to examine the effects of ingesting JavaFittrade mark Energy Extreme (JEE) on aerobic and anaerobic performance measures in recreationally-active male and female coffee drinkers. Five male (27.6 +/- 4.2 yrs, 93.2 +/- 11.7 kg, 181.6 +/- 6.9 cm) and five female (29 +/- 4.6 yrs, 61.5 +/- 9.2 kg, 167.6 +/- 6.9 cm) regular coffee drinkers (i.e., 223.9 +/- 62.7 mg.d-1 of caffeine) participated in this study. In a cross-over, randomized design, participants performed a baseline (BASELINE) graded treadmill test (GXT) for peak VO2 assessment and a Wingate test for peak power. Approximately 3-4 d following BASELINE testing, participants returned to the lab for the first trial and ingested 354 ml of either JEE or decaffeinated coffee (DECAF), after which they performed a GXT and Wingate test. Criterion measures during the GXT included an assessment of peakVO2 at maximal exercise, as well as VO2 at 3 minutes and 10 minutes post-exercise. Additionally, time-to-exhaustion (TTE), maximal RPE, mean heart rate (HR), mean systolic pressure (SBP), and mean diastolic blood pressure (DBP) were measured during each condition. Criterion measures for the Wingate included mean HR, SBP, DBP, peak power, and time to peak power (TTP). Participants then returned to the lab approximately one week later to perform the second trial under the same conditions as the first, except consuming the remaining coffee. Data were analyzed using a one way ANOVA (p < 0.05). Our results indicate that JEE significantly increased VO2 at 3 minutes post-exercise when compared to BASELINE (p = 0.04) and DECAF (p = 0.02) values, which may be beneficial in enhancing post-exercise fat metabolism. PMID:18067677

  13. Effects of ingesting JavaFit Energy Extreme functional coffee on aerobic and anaerobic fitness markers in recreationally-active coffee consumers

    Directory of Open Access Journals (Sweden)

    Kreider Richard B

    2007-12-01

    Full Text Available Abstract The purpose of this study was to examine the effects of ingesting JavaFit™ Energy Extreme (JEE on aerobic and anaerobic performance measures in recreationally-active male and female coffee drinkers. Five male (27.6 ± 4.2 yrs, 93.2 ± 11.7 kg, 181.6 ± 6.9 cm and five female (29 ± 4.6 yrs, 61.5 ± 9.2 kg, 167.6 ± 6.9 cm regular coffee drinkers (i.e., 223.9 ± 62.7 mg·d-1 of caffeine participated in this study. In a cross-over, randomized design, participants performed a baseline (BASELINE graded treadmill test (GXT for peak VO2 assessment and a Wingate test for peak power. Approximately 3–4 d following BASELINE testing, participants returned to the lab for the first trial and ingested 354 ml of either JEE or decaffeinated coffee (DECAF, after which they performed a GXT and Wingate test. Criterion measures during the GXT included an assessment of peakVO2 at maximal exercise, as well as VO2 at 3 minutes and 10 minutes post-exercise. Additionally, time-to-exhaustion (TTE, maximal RPE, mean heart rate (HR, mean systolic pressure (SBP, and mean diastolic blood pressure (DBP were measured during each condition. Criterion measures for the Wingate included mean HR, SBP, DBP, peak power, and time to peak power (TTP. Participants then returned to the lab approximately one week later to perform the second trial under the same conditions as the first, except consuming the remaining coffee. Data were analyzed using a one way ANOVA (p 2 at 3 minutes post-exercise when compared to BASELINE (p = 0.04 and DECAF (p = 0.02 values, which may be beneficial in enhancing post-exercise fat metabolism.

  14. Ghrelin O-acyltransferase (GOAT) and energy metabolism.

    Science.gov (United States)

    Li, Ziru; Mulholland, Michael; Zhang, Weizhen

    2016-03-01

    Ghrelin O-acyltransferase (GOAT), a member of MBOATs family, is essential for octanoylation of ghrelin, which is required for active ghrelin to bind with and activate its receptor. GOAT is expressed mainly in the stomach, pancreas and hypothalamus. Levels of GOAT are altered by energy status. GOAT contains 11 transmembrane helices and one reentrant loop. Its invariant residue His-338 and conserved Asn-307 are located in the endoplasmic reticulum lumen and cytosol respectively. GOAT contributes to the regulation of food intake and energy expenditure, as well as glucose and lipids homeostasis. Deletion of GOAT blocks the acylation of ghrelin leading to subsequent impairment in energy homeostasis and survival when mice are challenged with high energy diet or severe caloric restriction. GO-CoA-Tat, a peptide GOAT inhibitor, attenuates acyl-ghrelin production and prevents weight gain induced by a medium-chain triglycerides-rich high fat diet. Further, GO-CoA-Tat increases glucose- induced insulin secretion. Overall, inhibition of GOAT is a novel strategy for treatment of obesity and related metabolic disorders. PMID:26732975

  15. Research on the Characteristic of Energy Metabolism of Aerobics Sports and Reasonable Nutrition Supplement

    Directory of Open Access Journals (Sweden)

    Shuang Cheng

    2015-07-01

    Full Text Available The reasonable nutrition problem has received extensive attention. In this study, it takes the characteristics of aerobics sports as the breakthrough point, by analyzing the characteristics of energy metabolism of aerobics; it explains the composition of three large energy systems of energy metabolism, then discusses the nutritional requirements of Fitness Aerobics as well as the reasonable nutrition supplement measures.

  16. Research on the Characteristic of Energy Metabolism of Aerobics Sports and Reasonable Nutrition Supplement

    OpenAIRE

    Shuang Cheng

    2015-01-01

    The reasonable nutrition problem has received extensive attention. In this study, it takes the characteristics of aerobics sports as the breakthrough point, by analyzing the characteristics of energy metabolism of aerobics; it explains the composition of three large energy systems of energy metabolism, then discusses the nutritional requirements of Fitness Aerobics as well as the reasonable nutrition supplement measures.

  17. Islet transplantation in diabetic rats normalizes basal and exercise-induced energy metabolism

    NARCIS (Netherlands)

    Houwing, Harmina; Benthem, L.; Suylichem, P.T.R. van; Leest, J. van der; Strubbe, J.H.; Steffens, A.B.

    1995-01-01

    Transplantation of islets of Langerhans in diabetic rats normalizes resting glucose and insulin levels, but it remains unclear whether islet transplantation restores resting and exercise-induced energy metabolism. Therefore, we compared energy metabolism in islet transplanted rats with energy metabo

  18. Energy production from mechanical biological treatment and Composting plants exploiting solid anaerobic digestion batch: An Italian case study

    International Nuclear Information System (INIS)

    Highlights: ► This work quantifies the Italian Composting and MBT facilities upgradable by SADB. ► The bioCH4 from SADB of source and mechanical selected OFMSW is of 220–360 Nl/kg VS. ► The upgrading investment cost is 30% higher for Composting than for MBT. ► Electricity costs are 0.11–0.28 €/kW h, not influenced by differentiate collection. ► Electrical energy costs are constant for SADB treating more than 30 ktons/year. - Abstract: The energetic potential of the organic fraction of municipal solid waste processed in both existing Composting plants and Mechanical Biological Treatment (MBT) plants, can be successfully exploited by retrofitting these plants with the solid anaerobic digestion batch process. On the basis of the analysis performed in this study, about 50 MBT plants and 35 Composting plants were found to be suitable for retrofitting with Solid Anaerobic Digestion Batch (SADB) facilities. Currently the organic fraction of Municipal Solid Waste (OFMSW) arising from the MBT facilities is about 1,100,000 tons/year, whereas that arising from differentiated collection and treated in Composting plants is about 850,000 tons/year. The SADB performances were analyzed by the aid of an experimental apparatus and the main results, in agreement with literature data, show that the biogas yield ranged from 400 to 650 Nl/kg of Volatile Solids (VS), with a methane content ranging from 55% to 60% v/v. This can lead to the production of about 500 GW h of renewable energy per year, giving a CO2 reduction of about 270,000 tons/year. From the economic point of view, the analysis shows that the mean cost of a kW h of electrical energy produced by upgrading MBT and Composting facilities with the SADB, ranges from 0.11 and 0.28 €/kW h, depending on the plant size and the amount of waste treated.

  19. Effects of intracerebroventricular administration of neuropeptide Y on metabolic gene expression and energy metabolism in male rats

    NARCIS (Netherlands)

    Su, Yan; Foppen, Ewout; Fliers, Eric; Kalsbeek, A.

    2016-01-01

    Neuropeptide Y (NPY) is an important neurotransmitter in the control of energy metabolism. Several studies have shown that obesity is associated with increased levels of NPY in the hypothalamus. We hypothesized that the central release of NPY has coordinated and integrated effects on energy metaboli

  20. Molecular ecology of anaerobic reactor systems

    DEFF Research Database (Denmark)

    Hofman-Bang, H. Jacob Peider; Zheng, D.; Westermann, Peter;

    2003-01-01

    Anaerobic reactor systems are essential for the treatment of solid and liquid wastes and constitute a core facility in many waste treatment plants. Although much is known about the basic metabolism in different types of anaerobic reactors, little is known about the microbes responsible...... to the abundance of each microbe in anaerobic reactor systems by rRNA probing. This chapter focuses on various molecular techniques employed and problems encountered when elucidating the microbial ecology of anaerobic reactor systems. Methods such as quantitative dot blot/fluorescence in-situ probing using various...

  1. Construction and analysis of the model of energy metabolism in E. coli.

    Directory of Open Access Journals (Sweden)

    Zixiang Xu

    Full Text Available Genome-scale models of metabolism have only been analyzed with the constraint-based modelling philosophy and there have been several genome-scale gene-protein-reaction models. But research on the modelling for energy metabolism of organisms just began in recent years and research on metabolic weighted complex network are rare in literature. We have made three research based on the complete model of E. coli's energy metabolism. We first constructed a metabolic weighted network using the rates of free energy consumption within metabolic reactions as the weights. We then analyzed some structural characters of the metabolic weighted network that we constructed. We found that the distribution of the weight values was uneven, that most of the weight values were zero while reactions with abstract large weight values were rare and that the relationship between w (weight values and v (flux values was not of linear correlation. At last, we have done some research on the equilibrium of free energy for the energy metabolism system of E. coli. We found that E(out (free energy rate input from the environment can meet the demand of E(ch(in (free energy rate dissipated by chemical process and that chemical process plays a great role in the dissipation of free energy in cells. By these research and to a certain extend, we can understand more about the energy metabolism of E. coli.

  2. Actions of juglone on energy metabolism in the rat liver

    Energy Technology Data Exchange (ETDEWEB)

    Saling, Simoni Cristina; Comar, Jurandir Fernando; Mito, Marcio Shigueaki; Peralta, Rosane Marina; Bracht, Adelar, E-mail: adebracht@uol.com.br

    2011-12-15

    Juglone is a phenolic compound used in popular medicine as a phytotherapic to treat inflammatory and infectious diseases. However, it also acts as an uncoupler of oxidative phosphorylation in isolated liver mitochondria and, thus, may interfere with the hepatic energy metabolism. The purpose of this work was to evaluate the effect of juglone on several metabolic parameters in the isolated perfused rat liver. Juglone, in the concentration range of 5 to 50 {mu}M, stimulated glycogenolysis, glycolysis and oxygen uptake. Gluconeogenesis from both lactate and alanine was inhibited with half-maximal effects at the concentrations of 14.9 and 15.7 {mu}M, respectively. The overall alanine transformation was increased by juglone, as indicated by the stimulated release of ammonia, urea, L-glutamate, lactate and pyruvate. A great increase (9-fold) in the tissue content of {alpha}-ketoglutarate was found, without a similar change in the L-glutamate content. The tissue contents of ATP were decreased, but those of ADP and AMP were increased. Experiments with isolated mitochondria fully confirmed previous notions about the uncoupling action of juglone. It can be concluded that juglone is active on metabolism at relatively low concentrations. In this particular it resembles more closely the classical uncoupler 2,4-dinitrophenol. Ingestion of high doses of juglone, thus, presents the same risks as the ingestion of 2,4-dinitrophenol which comprise excessive compromising of ATP production, hyperthermia and even death. Low doses, i.e., moderate consumption of natural products containing juglone, however, could be beneficial to health if one considers recent reports about the consequences of chronic mild uncoupling. -- Highlights: Black-Right-Pointing-Pointer We investigated how juglone acts on liver metabolism. Black-Right-Pointing-Pointer The actions on hepatic gluconeogenesis, glycolysis and ureogenesis. Black-Right-Pointing-Pointer Juglone stimulates glycolysis and ureagenesis and

  3. Brain energy metabolism and blood flow differences in healthy aging

    DEFF Research Database (Denmark)

    Aanerud, Joel; Borghammer, Per; Chakravarty, M Mallar;

    2012-01-01

    Cerebral metabolic rate of oxygen consumption (CMRO(2)), cerebral blood flow (CBF), and oxygen extraction fraction (OEF) are important indices of healthy aging of the brain. Although a frequent topic of study, changes of CBF and CMRO(2) during normal aging are still controversial, as some authors...... years. The magnitudes of CMRO(2) and CBF declined in large parts of the cerebral cortex, including association areas, but the primary motor and sensory areas were relatively spared. We found significant increases of OEF in frontal and parietal cortices, excluding primary motor and somatosensory regions......, and in the temporal cortex. Because of the inverse relation between OEF and capillary oxygen tension, increased OEF can compromise oxygen delivery to neurons, with possible perturbation of energy turnover. The results establish a possible mechanism of progression from healthy to unhealthy brain aging, as the regions...

  4. Equine lamellar energy metabolism studied using tissue microdialysis.

    Science.gov (United States)

    Medina-Torres, C E; Pollitt, C C; Underwood, C; Castro-Olivera, E M; Collins, S N; Allavena, R E; Richardson, D W; van Eps, A W

    2014-09-01

    Failure of lamellar energy metabolism may contribute to the pathophysiology of equine laminitis. Tissue microdialysis has the potential to dynamically monitor lamellar energy balance over time. The objectives of this study were to develop a minimally invasive lamellar microdialysis technique and use it to measure normal lamellar energy metabolite concentrations over 24 h. Microdialysis probes were placed (through the white line) into either the lamellar dermis (LAM) (n = 6) or the sublamellar dermis (SUBLAM) (n = 6) and perfused continuously over a 24 h study period. Probes were placed in the skin dermis (SKIN) for simultaneous comparison to LAM (n = 6). Samples were collected every 2 h and analysed for glucose, lactate, pyruvate, urea and glycerol concentrations. LAM was further compared with SUBLAM by simultaneous placement and sampling in four feet from two horses over 4 h. Horses were monitored for lameness, and either clinically evaluated for 1 month after probe removal (n = 4) or subjected to histological evaluation of the probe site (n = 10). There were no deleterious clinical effects of probe placement and the histological response was mild. Sample fluid recovery and metabolite concentrations were stable for 24 h. Glucose was lower (and lactate:glucose ratio higher) in LAM compared with SUBLAM and SKIN (P laminitis pathogenesis. PMID:24947715

  5. Effects of sludge recirculation rate and mixing time on performance of a prototype single-stage anaerobic digester for conversion of food wastes to biogas and energy recovery.

    Science.gov (United States)

    Ratanatamskul, Chavalit; Saleart, Tawinan

    2016-04-01

    Food wastes have been recognized as the largest waste stream and accounts for 39.25 % of total municipal solid waste in Thailand. Chulalongkorn University has participated in the program of in situ energy recovery from food wastes under the Ministry of Energy (MOE), Thailand. This research aims to develop a prototype single-stage anaerobic digestion system for biogas production and energy recovery from food wastes inside Chulalongkorn University. Here, the effects of sludge recirculation rate and mixing time were investigated as the main key parameters for the system design and operation. From the results obtained in this study, it was found that the sludge recirculation rate of 100 % and the mixing time of 60 min per day were the most suitable design parameters to achieve high efficiencies in terms of chemical oxygen demand (COD), total solids (TS), and total volatile solid (TVS) removal and also biogas production by this prototype anaerobic digester. The obtained biogas production was found to be 0.71 m(3)/kg COD and the composition of methane was 61.6 %. Moreover, the efficiencies of COD removal were as high as 82.9 % and TVS removal could reach 83.9 % at the optimal condition. Therefore, the developed prototype single-stage anaerobic digester can be highly promising for university canteen application to recover energy from food wastes via biogas production.

  6. Effects of sludge recirculation rate and mixing time on performance of a prototype single-stage anaerobic digester for conversion of food wastes to biogas and energy recovery.

    Science.gov (United States)

    Ratanatamskul, Chavalit; Saleart, Tawinan

    2016-04-01

    Food wastes have been recognized as the largest waste stream and accounts for 39.25 % of total municipal solid waste in Thailand. Chulalongkorn University has participated in the program of in situ energy recovery from food wastes under the Ministry of Energy (MOE), Thailand. This research aims to develop a prototype single-stage anaerobic digestion system for biogas production and energy recovery from food wastes inside Chulalongkorn University. Here, the effects of sludge recirculation rate and mixing time were investigated as the main key parameters for the system design and operation. From the results obtained in this study, it was found that the sludge recirculation rate of 100 % and the mixing time of 60 min per day were the most suitable design parameters to achieve high efficiencies in terms of chemical oxygen demand (COD), total solids (TS), and total volatile solid (TVS) removal and also biogas production by this prototype anaerobic digester. The obtained biogas production was found to be 0.71 m(3)/kg COD and the composition of methane was 61.6 %. Moreover, the efficiencies of COD removal were as high as 82.9 % and TVS removal could reach 83.9 % at the optimal condition. Therefore, the developed prototype single-stage anaerobic digester can be highly promising for university canteen application to recover energy from food wastes via biogas production. PMID:25864735

  7. Potential Application of Anaerobic Extremophiles for Hydrogen Production

    Science.gov (United States)

    Pikuta, Elena V.; Hoover, Richard B.

    2004-01-01

    During substrate fermentation many anaerobes produce the hydrogen as a waste product, which often regulates the growth of the cultures as an inhibitor. In nature the hydrogen is usually removed from the ecosystem due to its physical properties or by consumption of hydrogen by secondary anaerobes, which sometimes behave as competitors for electron donors as is seen in the classical example in anaerobic microbial communities via the interaction between methanogens and sulfate- or sulfur- reducers. It was demonstrated previously on mixed cultures of anaerobes at neutral pH that bacterial hydrogen production could provide an alternative energy source. But at neutral pH the original cultures can easily be contaminated by methanogens, a most unpleasant side effect of these conditions is the development of pathogenic bacteria. In both cases the rate of hydrogen production was dramatically decreased since some part of the hydrogen was transformed to methane, and the cultivation of human pathogens on a global scale is very dangerous. In our laboratory, experiments with obligately alkaliphilic bacteria that excrete hydrogen as the end metabolic product were performed at different temperature regimes. Mesophilic and moderately thermophilic bacterial cultures have been studied and compared for the most effective hydrogen production. For high-mineralized media with pH 9.5-10.0 not many methanogens are known to exist. Furthermore, the development of pathogenic contaminant microorganisms is virtually impossible: carbonate-saturated solutions are used as antiseptics in medicine. Therefore the cultivation of alkaliphilic hydrogen producing bacteria could be considered as most safe process for global Scale industry in future. Here we present experimental data on the rates of hydrogen productivity for mesophilic, alkaliphilic, obligately anaerobic bacterium Spirocheta americana ASpG1 and moderately thermophilic, alkaliphilic, facultative anaerobe Anoxybacillus pushchinoensis K1 and

  8. Emerging role of the brain in the homeostatic regulation of energy and glucose metabolism.

    Science.gov (United States)

    Roh, Eun; Song, Do Kyeong; Kim, Min-Seon

    2016-01-01

    Accumulated evidence from genetic animal models suggests that the brain, particularly the hypothalamus, has a key role in the homeostatic regulation of energy and glucose metabolism. The brain integrates multiple metabolic inputs from the periphery through nutrients, gut-derived satiety signals and adiposity-related hormones. The brain modulates various aspects of metabolism, such as food intake, energy expenditure, insulin secretion, hepatic glucose production and glucose/fatty acid metabolism in adipose tissue and skeletal muscle. Highly coordinated interactions between the brain and peripheral metabolic organs are critical for the maintenance of energy and glucose homeostasis. Defective crosstalk between the brain and peripheral organs contributes to the development of obesity and type 2 diabetes. Here we comprehensively review the above topics, discussing the main findings related to the role of the brain in the homeostatic regulation of energy and glucose metabolism. PMID:26964832

  9. Farm-scale anaerobic digestion of beef and dairy cattle manure for energy cogeneration at two farms in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Patni, N.; Monreal, C. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada); Li, X. [Highmark Renewables Research, Calgary, AB (Canada); Crolla, A.; Kinsley, C. [Guelph Univ., Alfred Campus, Alfred, ON (Canada); Barclay, J. [Environment Canada, Ottawa, ON (Canada). Emerging Fuel Issues Div.

    2010-07-01

    This paper reported on a study that was conducted in 2003 to 2005 at beef and diary cattle farms in Canada, where cattle manure was anaerobically digested for biogas production. The biogas was used for electrical and thermal energy cogeneration. Manure from about 7500 beef cattle at a feedlot was digested at a thermophilic temperature of 55 degrees C in two 1800 m{sup 3} above-ground digesters with a hydraulic retention time (HRT) of 14 days. The biogas had an average 58 per cent methane content and was combusted in a General Electric Jenbacher 999 kW cogeneration system. At the second farm, manure from about 165 lactating cows, 110 heifers and 40 calves was digested at a mesophilic temperature of 40 degrees C in a 500 m{sup 3} below-ground digester with a HRT of 28 days. The unique feature of this digester was that it was retrofitted in a pre-existing larger slurry storage tank. The biogas had an average 65 per cent methane content and was combusted in a 75 kW Perkins dual fuel diesel engine connected to a 65 kW Schnell generator. In 2007, when fats, oils and grease (FOG) from restaurant waste residue was added to the manure, biogas production increased by about 300 per cent and electrical energy generation increased by 180 per cent. Both systems have operated year-round from December to February at average ambient temperatures that ranged from -9 to -12 degrees Celsius. This paper addressed the long-term sustainability options for animal farm operations in terms of biogas production for electricity and thermal energy cogeneration.

  10. The plasma membrane as a capacitor for energy and metabolism.

    Science.gov (United States)

    Ray, Supriyo; Kassan, Adam; Busija, Anna R; Rangamani, Padmini; Patel, Hemal H

    2016-02-01

    When considering which components of the cell are the most critical to function and physiology, we naturally focus on the nucleus, the mitochondria that regulate energy and apoptotic signaling, or other organelles such as the endoplasmic reticulum, Golgi, ribosomes, etc. Few people will suggest that the membrane is the most critical element of a cell in terms of function and physiology. Those that consider the membrane critical will point to its obvious barrier function regulated by the lipid bilayer and numerous ion channels that regulate homeostatic gradients. What becomes evident upon closer inspection is that not all membranes are created equal and that there are lipid-rich microdomains that serve as platforms of signaling and a means of communication with the intracellular environment. In this review, we explore the evolution of membranes, focus on lipid-rich microdomains, and advance the novel concept that membranes serve as "capacitors for energy and metabolism." Within this framework, the membrane then is the primary and critical regulator of stress and disease adaptation of the cell.

  11. Sustainable organic loading rate and energy recovery potential of mesophilic anaerobic membrane bioreactor for municipal wastewater treatment.

    Science.gov (United States)

    Wei, Chun-Hai; Harb, Moustapha; Amy, Gary; Hong, Pei-Ying; Leiknes, TorOve

    2014-08-01

    The overall performance of a mesophilic anaerobic membrane bioreactor (AnMBR) for synthetic municipal wastewater treatment was investigated under a range of organic loading rate (OLR). A very steady and high chemical oxygen demand (COD) removal (around 98%) was achieved over a broad range of volumetric OLR of 0.8-10 gCOD/L/d. The sustainable volumetric and sludge OLR satisfying a permeate COD below 50 mg/L for general reuse was 6 gCOD/L/d and 0.63 gCOD/gMLVSS (mixed liquor volatile suspended solids)/d, respectively. At a high sludge OLR of over 0.6 gCOD/gMLVSS/d, the AnMBR achieved high methane production of over 300 ml/gCOD (even approaching the theoretical value of 382 ml/gCOD). A low biomass production of 0.015-0.026 gMLVSS/gCOD and a sustainable flux of 6L/m(2)/h were observed. The integration of a heat pump and forward osmosis into the mesophilic AnMBR process would be a promising way for net energy recovery from typical municipal wastewater in a temperate area. PMID:24926606

  12. Energy conversion of biomass crops and agroindustrial residues by combined biohydrogen/biomethane system and anaerobic digestion.

    Science.gov (United States)

    Corneli, Elisa; Dragoni, Federico; Adessi, Alessandra; De Philippis, Roberto; Bonari, Enrico; Ragaglini, Giorgio

    2016-07-01

    Aim of this study was to evaluate the suitability of ensiled giant reed, ensiled maize, ensiled olive pomace, wheat bran for combined systems (CS: dark fermentation+anaerobic digestion (AD)) producing hydrogen-rich biogas (biohythane), tested in batch under basic operational conditions (mesophilic temperatures, no pH control). Substrates were also analyzed under a single stage AD batch test, in order to investigate the effects of DF on estimated energy recovery (ER) in combined systems. In CS, maize and wheat bran exhibited the highest hydrogen potential (13.8 and 18.9NLkgVS(-1)) and wheat bran the highest methane potential (243.5NLkgVS(-1)). In one-stage AD, giant reed, maize and wheat bran showed the highest methane production (239.5, 267.3 and 260.0NLkgVS(-1)). Butyrate/acetate ratio properly described the dark fermentation, correlating with hydrogen production (r=0.92). Wheat bran proved to be a promising residue for CS in terms of hydrogen/methane potential and ER. PMID:27038259

  13. Energy conversion of biomass crops and agroindustrial residues by combined biohydrogen/biomethane system and anaerobic digestion.

    Science.gov (United States)

    Corneli, Elisa; Dragoni, Federico; Adessi, Alessandra; De Philippis, Roberto; Bonari, Enrico; Ragaglini, Giorgio

    2016-07-01

    Aim of this study was to evaluate the suitability of ensiled giant reed, ensiled maize, ensiled olive pomace, wheat bran for combined systems (CS: dark fermentation+anaerobic digestion (AD)) producing hydrogen-rich biogas (biohythane), tested in batch under basic operational conditions (mesophilic temperatures, no pH control). Substrates were also analyzed under a single stage AD batch test, in order to investigate the effects of DF on estimated energy recovery (ER) in combined systems. In CS, maize and wheat bran exhibited the highest hydrogen potential (13.8 and 18.9NLkgVS(-1)) and wheat bran the highest methane potential (243.5NLkgVS(-1)). In one-stage AD, giant reed, maize and wheat bran showed the highest methane production (239.5, 267.3 and 260.0NLkgVS(-1)). Butyrate/acetate ratio properly described the dark fermentation, correlating with hydrogen production (r=0.92). Wheat bran proved to be a promising residue for CS in terms of hydrogen/methane potential and ER.

  14. Sustainable organic loading rate and energy recovery potential of mesophilic anaerobic membrane bioreactor for municipal wastewater treatment

    KAUST Repository

    Wei, Chunhai

    2014-08-01

    The overall performance of a mesophilic anaerobic membrane bioreactor (AnMBR) for synthetic municipal wastewater treatment was investigated under a range of organic loading rate (OLR). A very steady and high chemical oxygen demand (COD) removal (around 98%) was achieved over a broad range of volumetric OLR of 0.8-10gCOD/L/d. The sustainable volumetric and sludge OLR satisfying a permeate COD below 50mg/L for general reuse was 6gCOD/L/d and 0.63gCOD/gMLVSS (mixed liquor volatile suspended solids)/d, respectively. At a high sludge OLR of over 0.6gCOD/gMLVSS/d, the AnMBR achieved high methane production of over 300ml/gCOD (even approaching the theoretical value of 382ml/gCOD). A low biomass production of 0.015-0.026gMLVSS/gCOD and a sustainable flux of 6L/m2/h were observed. The integration of a heat pump and forward osmosis into the mesophilic AnMBR process would be a promising way for net energy recovery from typical municipal wastewater in a temperate area. © 2014 Elsevier Ltd.

  15. INFLUENCE OF METRONIDAZOLE, CO, CO2, AND METHANOGENS ON THE FERMENTATIVE METABOLISM OF THE ANAEROBIC FUNGUS NEOCALLIMASTIX SP STRAIN L2

    NARCIS (Netherlands)

    MARVINSIKKEMA, FD; REES, E; KRAAK, MN; GOTTSCHAL, JC; PRINS, RA

    1993-01-01

    The effects of metronidazole, CO, methanogens, and CO, on the fermentation of glucose by the anaerobic fungus Neocallimastix sp. strain L2 were investigated. Both metronidazole and CO caused a shift in the fermentation products from predominantly H-2, acetate, and formate to lactate as the major pro

  16. A model‐driven quantitative metabolomics analysis of aerobic and anaerobic metabolism in E. coli K‐12 MG1655 that is biochemically and thermodynamically consistent

    DEFF Research Database (Denmark)

    McCloskey, Douglas; Gangoiti, Jon A.; King, Zachary A.;

    2014-01-01

    in metabolomes between anaerobic and aerobic growth of Escherichia coli. Constraint‐based modeling was utilized to deduce a target list of compounds for downstream method development. An analytical and experimental methodology was developed and tailored to the compound chemistry and growth conditions of interest...

  17. Bone: from a reservoir of minerals to a regulator of energy metabolism

    OpenAIRE

    Confavreux, Cyrille B.

    2011-01-01

    Besides locomotion, organ protection, and calcium–phosphorus homeostasis, the three classical functions of the skeleton, bone remodeling affects energy metabolism through uncarboxylated osteocalcin, a recently discovered hormone secreted by osteoblasts. This review traces how energy metabolism affects osteoblasts through the central control of bone mass involving leptin, serotoninergic neurons, the hypothalamus, and the sympathetic nervous system. Next, the role of osteocalcin (insulin secret...

  18. Human longevity is characterised by high thyroid stimulating hormone secretion without altered energy metabolism

    DEFF Research Database (Denmark)

    Jansen, S W; Akintola, A A; Roelfsema, F;

    2015-01-01

    hormone (TH) in an inverse relationship. Greater longevity has been associated with higher TSH and lower TH levels, but mechanisms underlying TSH/TH differences and longevity remain unknown. The HPT axis plays a pivotal role in growth, development and energy metabolism. We report that offspring...... may favour longevity without altering energy metabolism....

  19. Metabolism

    Science.gov (United States)

    ... a particular food provides to the body. A chocolate bar has more calories than an apple, so ... More Common in People With Type 1 Diabetes Metabolic Syndrome Your Child's Weight Healthy Eating Endocrine System Blood ...

  20. Metabolomics analysis of Cistus monspeliensis leaf extract on energy metabolism activation in human intestinal cells.

    Science.gov (United States)

    Shimoda, Yoichi; Han, Junkyu; Kawada, Kiyokazu; Smaoui, Abderrazak; Isoda, Hiroko

    2012-01-01

    Energy metabolism is a very important process to improve and maintain health from the point of view of physiology. It is well known that the intracellular ATP production is contributed to energy metabolism in cells. Cistus monspeliensis is widely used as tea, spices, and medical herb; however, it has not been focusing on the activation of energy metabolism. In this study, C. monspeliensis was investigated as the food resources by activation of energy metabolism in human intestinal epithelial cells. C. monspeliensis extract showed high antioxidant ability. In addition, the promotion of metabolites of glycolysis and TCA cycle was induced by C. monspeliensis treatment. These results suggest that C. monspeliensis extract has an ability to enhance the energy metabolism in human intestinal cells. PMID:22523469

  1. Metabolomics Analysis of Cistus monspeliensis Leaf Extract on Energy Metabolism Activation in Human Intestinal Cells

    Directory of Open Access Journals (Sweden)

    Yoichi Shimoda

    2012-01-01

    Full Text Available Energy metabolism is a very important process to improve and maintain health from the point of view of physiology. It is well known that the intracellular ATP production is contributed to energy metabolism in cells. Cistus monspeliensis is widely used as tea, spices, and medical herb; however, it has not been focusing on the activation of energy metabolism. In this study, C. monspeliensis was investigated as the food resources by activation of energy metabolism in human intestinal epithelial cells. C. monspeliensis extract showed high antioxidant ability. In addition, the promotion of metabolites of glycolysis and TCA cycle was induced by C. monspeliensis treatment. These results suggest that C. monspeliensis extract has an ability to enhance the energy metabolism in human intestinal cells.

  2. Erythropoietin, a novel versatile player regulating energy metabolism beyond the erythroid system.

    Science.gov (United States)

    Wang, Li; Di, Lijun; Noguchi, Constance Tom

    2014-01-01

    Erythropoietin (EPO), the required cytokine for promoting the proliferation and differentiation of erythroid cells to stimulate erythropoiesis, has been reported to act as a pleiotropic cytokine beyond hematopoietic system. The various activities of EPO are determined by the widespread distribution of its cell surface EPO receptor (EpoR) in multiple tissues including endothelial, neural, myoblasts, adipocytes and other cell types. EPO activity has been linked to angiogenesis, neuroprotection, cardioprotection, stress protection, anti-inflammation and especially the energy metabolism regulation that is recently revealed. The investigations of EPO activity in animals and the expression analysis of EpoR provide more insights on the potential of EPO in regulating energy metabolism and homeostasis. The findings of crosstalk between EPO and some important energy sensors and the regulation of EPO in the cellular respiration and mitochondrial function further provide molecular mechanisms for EPO activity in metabolic activity regulation. In this review, we will summarize the roles of EPO in energy metabolism regulation and the activity of EPO in tissues that are tightly associated with energy metabolism. We will also discuss the effects of EPO in regulating oxidative metabolism and mitochondrial function, the interactions between EPO and important energy regulation factors, and the protective role of EPO from stresses that are related to metabolism, providing a brief overview of previously less appreciated EPO biological function in energy metabolism and homeostasis. PMID:25170305

  3. Calorie Restriction-like Effects of 30 Days of Resveratrol Supplementation on Energy Metabolism and Metabolic Profile in Obese Humans

    NARCIS (Netherlands)

    Timmers, S.; Konings, E.; Bilet, L.; Houtkooper, R.H.; Weijer, van de T.; Goossens, G.H.; Hoeks, J.; Krieken, van der S.; Ryu, D.; Kersten, A.H.; Moonen-Kornips, E.; Hesselink, M.K.C.; Kunz, I.; Schrauwen-Hinderling, V.B.; Blaak, E.E.; Auwerx, J.; Schrauwen, P.

    2011-01-01

    Resveratrol is a natural compound that affects energy metabolism and mitochondrial function and serves as a calorie restriction mimetic, at least in animal models of obesity. Here, we treated 11 healthy, obese men with placebo and 150 mg/day resveratrol (resVida) in a randomized double-blind crossov

  4. Going beyond energy intensity to understand the energy metabolism of nations: The case of Argentina

    International Nuclear Information System (INIS)

    The link between energy consumption and economic growth has been widely studied in the economic literature. Understanding this relationship is important from both an environmental and a socio-economic point of view, as energy consumption is crucial to economic activity and human environmental impact. This relevance is even higher for developing countries, since energy consumption per unit of output varies through the phases of development, increasing from an agricultural stage to an industrial one and then decreasing for certain service based economies. In the Argentinean case, the relevance of energy consumption to economic development seems to be particularly important. While energy intensity seems to exhibit a U-Shaped curve from 1990 to 2003 decreasing slightly after that year, total energy consumption increases along the period of analysis. Why does this happen? How can we relate this result with the sustainability debate? All these questions are very important due to Argentinean hydrocarbons dependence and due to the recent reduction in oil and natural gas reserves, which can lead to a lack of security of supply. In this paper we study Argentinean energy consumption pattern for the period 1990–2007, to discuss current and future energy and economic sustainability. To this purpose, we developed a conventional analysis, studying energy intensity, and a non conventional analysis, using the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) accounting methodology. Both methodologies show that the development process followed by Argentina has not been good enough to assure sustainability in the long term. Instead of improving energy use, energy intensity has increased. The current composition of its energy mix, and the recent economic crisis in Argentina, as well as its development path, are some of the possible explanations. -- Highlights: ► We analyze Argentinean energy consumption and social metabolism using MuSIASEM.

  5. One step beyond a ribosome: The ancient anaerobic core.

    Science.gov (United States)

    Sousa, Filipa L; Nelson-Sathi, Shijulal; Martin, William F

    2016-08-01

    Life arose in a world without oxygen and the first organisms were anaerobes. Here we investigate the gene repertoire of the prokaryote common ancestor, estimating which genes it contained and to which lineages of modern prokaryotes it was most similar in terms of gene content. Using a phylogenetic approach we found that among trees for all 8779 protein families shared between 134 archaea and 1847 bacterial genomes, only 1045 have sequences from at least two bacterial and two archaeal groups and retain the ancestral archaeal-bacterial split. Among those, the genes shared by anaerobes were identified as candidate genes for the prokaryote common ancestor, which lived in anaerobic environments. We find that these anaerobic prokaryote common ancestor genes are today most frequently distributed among methanogens and clostridia, strict anaerobes that live from low free energy changes near the thermodynamic limit of life. The anaerobic families encompass genes for bifunctional acetyl-CoA-synthase/CO-dehydrogenase, heterodisulfide reductase subunits C and A, ferredoxins, and several subunits of the Mrp-antiporter/hydrogenase family, in addition to numerous S-adenosyl methionine (SAM) dependent methyltransferases. The data indicate a major role for methyl groups in the metabolism of the prokaryote common ancestor. The data furthermore indicate that the prokaryote ancestor possessed a rotor stator ATP synthase, but lacked cytochromes and quinones as well as identifiable redox-dependent ion pumping complexes. The prokaryote ancestor did possess, however, an Mrp-type H(+)/Na(+) antiporter complex, capable of transducing geochemical pH gradients into biologically more stable Na(+)-gradients. The findings implicate a hydrothermal, autotrophic, and methyl-dependent origin of life. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi. PMID:27150504

  6. Rh2E2, a novel metabolic suppressor, specifically inhibits energy-based metabolism of tumor cells.

    Science.gov (United States)

    Wong, Vincent Kam Wai; Dong, Hang; Liang, Xu; Bai, Li-Ping; Jiang, Zhi-Hong; Guo, Yue; Kong, Ah Ng Tony; Wang, Rui; Kam, Richard Kin Ting; Law, Betty Yuen Kwan; Hsiao, Wendy Wen Luen; Chan, Ka Man; Wang, Jingrong; Chan, Rick Wai Kit; Guo, Jianru; Zhang, Wei; Yen, Feng Gen; Zhou, Hua; Leung, Elaine Lai Han; Yu, Zhiling; Liu, Liang

    2016-03-01

    Energy metabolism in cancer cells is often increased to meet their higher proliferative rate and biosynthesis demands. Suppressing cancer cell metabolism using agents like metformin has become an attractive strategy for treating cancer patients. We showed that a novel ginsenoside derivative, Rh2E2, is as effective as aspirin in preventing the development of AOM/DSS-induced colorectal cancer and suppresses tumor growth and metastasis in a LLC-1 xenograft. A sub-chronic and acute toxicity LD50 test of Rh2E2 showed no harmful reactions at the maximum oral dosage of 5000 mg/kg body weight in mice. Proteomic profiling revealed that Rh2E2 specifically inhibited ATP production in cancer cells via down-regulation of metabolic enzymes involving glycolysis, fatty acid β-oxidation and the tricarboxylic acid cycle, leading to specific cytotoxicity and S-phase cell cycle arrest in cancer cells. Those findings suggest that Rh2E2 possesses a novel and safe anti-metabolic agent for cancer patients by specific reduction of energy-based metabolism in cancer cells. PMID:26799418

  7. Anaerobic biological treatment

    International Nuclear Information System (INIS)

    The Enso-Fenox process has been very successfully used to remove chlorinated phenolic compounds from pulp bleaching effluents. It is a two-stage anaerobic/aerobic process consisting of a nonmethanogenic anaerobic fluidized bed followed by a trickling filter. Studies have been conducted on reductive dechlorination of chlorinated aromatic compounds under anaerobic conditions with chlorinated phenols as the sole carbon and energy source. Approximately 40% of the added chlorophenols was converted to CH4 and CO2. Substrate loading rates were 20 mg/L/d at hydraulic detention times of 2-4 days with 90% substrate conversion efficiency. Reductive dechlorination of mono, di-, tri-, and pentachlorophenols has been demonstrated in anaerobic sewage sludge. The following constituents were tested in the laboratory at their approximate concentrations in coal conversion wastewater (CCWW) and were anaerobically degraded in serum bottles: 1,000 mg/L phenol; 500 mg/L resorcinol; 1,000 mg/L benzoic acid; 500 mg/L p-cresol; 200 mg/L pyridine; 2,000 mg/L benzoic acid; 250 mg/L 40 methylcatechol; 500 mg/L 4-ethylpyridine; and 2,000 mg/L hexanoic acid. A petrochemical may initially exhibit toxicity to an unacclimated population of methane-fermenting bacteria, but with acclimation the toxicity may be greatly reduced or disappear. In addition, the microorganisms may develop the capacity to actually degrade compounds which showed initial toxicity. Since biomass digestion requires a complete consortium of bacteria, it is relevant to study the effect of a given process as well as to individual steps within the process. A toxicant can inhibit the rate-limiting step and/or change the step that is rate-limiting. Both manifestations of toxicity can severely affect the overall process

  8. The effect of anaerobic fermentation processing of cattle waste for biogas as a renewable energy resources on the number of contaminant microorganism

    Science.gov (United States)

    Kurnani, Tb. Benito A.; Hidayati, Yuli Astuti; Marlina, Eulis Tanti; Harlia, Ellin

    2016-02-01

    Beef cattle waste has a positive potential that can be exploited, as well as a negative potential that must be controlled so as not to pollute the environment. Beef cattle waste can be processed into an alternative energy, namely biogas. Anaerobic treatment of livestock waste to produce gas can be a solution in providing optional energy, while the resulted sludge as the fermentation residue can be used as organic fertilizer for crops. However, this sludge may containt patogenic microorganism that will damage human and environmet healt. Therefor, this study was aimed to know the potency of beef cattle waste to produce biogas and the decrease of the microorganism's number by using fixed dome digester. Beef cattle waste was processed into biogas using fixed dome digester with a capacity of 12 m3. Biogas composition was measured using Gas Cromatografi, will microorganism species was identified using Total plate Count Methode. The result of this study shows that the produced biogas contains of 75.77% Mol (CH4), 13.28% Mol (N), and 6.96% Mol (CO2). Furthermor, this study show that the anaerobic fermrntation process is capable of reducing microorganisms that could potentially pollute the environment. The number of Escherichia coli and Samonella sp. were waste before, and after anaerobic fermentation was merely Eimeria sp.. The process also reduced the yeast of 86.11%. The remaining yeast after fermentation was Candida sp. Finally, about 93.7% of endoparasites was reduced by this process. In this case, every trematode and cestoda were 100% reduced, while the nematode only 75%. Reducing some microorganisms that have the potential to pollute the environment signifies sludge anaerobic fermentation residue is safe to be applied as organic fertilizer for crops.

  9. The effect of anaerobic fermentation processing of cattle waste for biogas as a renewable energy resources on the number of contaminant microorganism

    Science.gov (United States)

    Kurnani, Tb. Benito A.; Hidayati, Yuli Astuti; Marlina, Eulis Tanti; Harlia, Ellin

    2016-02-01

    Beef cattle waste has a positive potential that can be exploited, as well as a negative potential that must be controlled so as not to pollute the environment. Beef cattle waste can be processed into an alternative energy, namely biogas. Anaerobic treatment of livestock waste to produce gas can be a solution in providing optional energy, while the resulted sludge as the fermentation residue can be used as organic fertilizer for crops. However, this sludge may containt patogenic microorganism that will damage human and environmet healt. Therefor, this study was aimed to know the potency of beef cattle waste to produce biogas and the decrease of the microorganism's number by using fixed dome digester. Beef cattle waste was processed into biogas using fixed dome digester with a capacity of 12 m3. Biogas composition was measured using Gas Cromatografi, will microorganism species was identified using Total plate Count Methode. The result of this study shows that the produced biogas contains of 75.77% Mol (CH4), 13.28% Mol (N), and 6.96% Mol (CO2). Furthermor, this study show that the anaerobic fermrntation process is capable of reducing microorganisms that could potentially pollute the environment. The number of Escherichia coli and Samonella sp. were cattle waste before, and after anaerobic fermentation was merely Eimeria sp.. The process also reduced the yeast of 86.11%. The remaining yeast after fermentation was Candida sp. Finally, about 93.7% of endoparasites was reduced by this process. In this case, every trematode and cestoda were 100% reduced, while the nematode only 75%. Reducing some microorganisms that have the potential to pollute the environment signifies sludge anaerobic fermentation residue is safe to be applied as organic fertilizer for crops.

  10. Anaerobic biodegradability of macropollutants

    DEFF Research Database (Denmark)

    Angelidaki, Irini

    2002-01-01

    A variety of test procedures for determination of anaerobic biodegradability has been reported. This paper reviews the methods developed for determination of anaerobic biodegradability of macro-pollutants. Anaerobic biodegradability of micro-pollutants is not included. Furthermore, factors import...

  11. Energy balance, greenhouse gas emissions, and profitability of thermobarical pretreatment of cattle waste in anaerobic digestion.

    Science.gov (United States)

    Budde, Jörn; Prochnow, Annette; Plöchl, Matthias; Suárez Quiñones, Teresa; Heiermann, Monika

    2016-03-01

    In this study modeled full scale application of thermobarical hydrolysis of less degradable feedstock for biomethanation was assessed in terms of energy balance, greenhouse gas emissions, and economy. Data were provided whether the substitution of maize silage as feedstock for biogas production by pretreated cattle wastes is beneficial in full-scale application or not. A model device for thermobarical treatment has been suggested for and theoretically integrated in a biogas plant. The assessment considered the replacement of maize silage as feedstock with liquid and/or solid cattle waste (feces, litter, and feed residues from animal husbandry of high-performance dairy cattle, dry cows, and heifers). The integration of thermobarical pretreatment is beneficial for raw material with high contents of organic dry matter and ligno-cellulose: Solid cattle waste revealed very short payback times, e.g. 9 months for energy, 3 months for greenhouse gases, and 3 years 3 months for economic amortization, whereas, in contrast, liquid cattle waste did not perform positive replacement effects in this analysis.

  12. Energy metabolism of overweight women before, during and after weight reduction assessed by indirect calorimetry.

    NARCIS (Netherlands)

    Groot, de C.P.G.M.

    1988-01-01

    Previous studies had suggested that periods of low energy intake evoke compensatory adaptations in energy metabolism, which retard weight loss, and promote weight regain when energy intake returns to normal. The aim of this thesis was to investigate whether a slimming (low-energy) diet based on alte

  13. Thermodynamics of Microbial Growth Coupled to Metabolism of Glucose, Ethanol, Short-Chain Organic Acids, and Hydrogen ▿ †

    Science.gov (United States)

    Roden, Eric E.; Jin, Qusheng

    2011-01-01

    A literature compilation demonstrated a linear relationship between microbial growth yield and the free energy of aerobic and anaerobic (respiratory and/or fermentative) metabolism of glucose, ethanol, formate, acetate, lactate, propionate, butyrate, and H2. This relationship provides a means to estimate growth yields for modeling microbial redox metabolism in soil and sedimentary environments. PMID:21216913

  14. Anaerobic Digestion Scale Levels and Their Energy Yields. A comparison of energy yields of different manure-and co-digestion scale levels

    NARCIS (Netherlands)

    Konneman, Bram

    2007-01-01

    Anaerobic digestion is a biological process whereby, in the absence of oxygen, organic matter is converted into biogas and digestate. In recent years anaerobic digestion has received re-newed attention in the Dutch agricultural sector. Co-digestion, in wh

  15. Anaerobic energy production and O2 deficit-debt relationship during exhaustive exercise in humans

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Gollnick, PD; Graham, T;

    1990-01-01

    before and immediately after the intense exercise, and at 3, 10 and 60 min into recovery. 2. Individual linear relations (r = 0.95-1.00) between the power outputs for submaximal exercise and oxygen uptakes (leg and pulmonary) were used to estimate the energy demand during intense exercise. Pulmonary...... release was 14.8 mmol (kg wet wt)-1 or about 1/3 of the total net lactate production. During recovery 70% of the accumulated lactate was released to the blood, and the nucleotides and CP returned to about 40 and 85% of pre-exercise values at 3 and 10 min of recovery, respectively. 4. Total reduction...... in ATP and CP (and elevation of IMP) during the intense exercise amounted to 16.4 mmol ATP (kg wet wt)-1, which together with the lactate production accounted for 83.1 mmol ATP (kg wet wt)-1. In addition 6-8 mmol ATP (kg wet wt)-1 are made available related to accumulation of glycolytic intermediates...

  16. Bedside Evaluation of Cerebral Energy Metabolism in Severe Community-Acquired Bacterial Meningitis

    DEFF Research Database (Denmark)

    Rom Poulsen, Frantz; Schulz, Mette; Jacobsen, Anne;

    2015-01-01

    BACKGROUND: Mortality and morbidity have remained high in bacterial meningitis. Impairment of cerebral energy metabolism probably contributes to unfavorable outcome. Intracerebral microdialysis is routinely used to monitor cerebral energy metabolism, and recent experimental studies indicate...... that this technique may separate ischemia and non-ischemic mitochondrial dysfunction. The present study is a retrospective interpretation of biochemical data obtained in a series of patients with severe community-acquired meningitis. METHODS: Cerebral energy metabolism was monitored in 15 patients with severe...... community-acquired meningitis utilizing intracerebral microdialysis and bedside biochemical analysis. According to previous studies, cerebral ischemia was defined as lactate/pyruvate (LP) ratio >30 with intracerebral pyruvate level

  17. Substrate-energy metabolism and metabolic risk factors for cardiovascular disease in relation to fetal growth and adult body composition.

    Science.gov (United States)

    Kensara, Osama A; Wooton, Steve A; Phillips, David I W; Patel, Mayank; Hoffman, Daniel J; Jackson, Alan A; Elia, Marinos

    2006-08-01

    The effect of fetal programming on intermediary metabolism is uncertain. Therefore, we examined whether fetal programming affects oxidative and nonoxidative macronutrient metabolism and the prevalence of the metabolic syndrome in adult life. Healthy older men, aged 64-72 years, with either a lower birth weight (LBW, or=75th %ile; n = 13) had measurements of 1) net oxidative metabolism using indirect calorimetry before and for 6 h after a mixed meal (3,720 kJ) and 2) postprandial oxidation of exogenous [13C]palmitic acid. Body composition was measured using dual-energy X-ray absorptiometry. After adjustment for current weight and height, the LBW group had a lower resting energy expenditure (REE) in the preprandial (4.01 vs. 4.54 kJ/min, P = 0.015) and postprandial state (4.60 vs. 5.20 kJ/min, P = 0.004), and less fat-free mass than the HBW group. The BW category was a significant, independent, and better predictor of REE than weight plus height. There were no significant differences between groups in net oxidative and nonoxidative macronutrient (protein, fat, carbohydrate) metabolism (or of exogenous [13C]palmitate) or in the prevalence of the metabolic syndrome, which was present almost twice as commonly in the LBW than in the HBW group. The study suggests that fetal programming affects both pre- and postprandial EE in older life by mechanisms that are at least partly related to the mass of the fat-free body. BW was found to be a significant predictor of REE that was independent of adult weight plus height.

  18. The energy-saving anaerobic baffled reactor membrane bioreactor (EABR-MBR) system for recycling wastewater from a high-rise building.

    Science.gov (United States)

    Ratanatamskul, Chavalit; Charoenphol, Chakraphan

    2015-01-01

    A novel energy-saving anaerobic baffled reactor-membrane bioreactor (EABR-MBR) system has been developed as a compact biological treatment system for reuse of water from a high-rise building. The anaerobic baffled reactor (ABR) compartment had five baffles and served as the anaerobic degradation zone, followed by the aerobic MBR compartment. The total operating hydraulic retention time (HRT) of the EABR-MBR system was 3 hours (2 hours for ABR compartment and very short HRT of 1 hour for aerobic MBR compartment). The wastewater came from the Charoen Wisawakam building. The results showed that treated effluent quality was quite good and highly promising for water reuse purposes. The average flux of the membrane was kept at 30 l/(m2h). The EABR-MBR system could remove chemical oxygen demand, total nitrogen and total phosphorus from building wastewater by more than 90%. Moreover, it was found that phosphorus concentration was rising in the ABR compartment due to the phosphorus release phenomenon, and then the concentration decreased rapidly in the aerobic MBR compartment due to the phosphorus uptake phenomenon. This implies that phosphorus-accumulating organisms inside the EABR-MBR system are responsible for biological phosphorus removal. The research suggests that the EABR-MBR system can be a promising system for water reuse and reclamation for high-rise building application in the near future. PMID:26067504

  19. Impact of Ocean Acidification on Energy Metabolism of Oyster, Crassostrea gigas—Changes in Metabolic Pathways and Thermal Response

    Directory of Open Access Journals (Sweden)

    Christian Bock

    2010-08-01

    Full Text Available Climate change with increasing temperature and ocean acidification (OA poses risks for marine ecosystems. According to Pörtner and Farrell [1], synergistic effects of elevated temperature and CO2-induced OA on energy metabolism will narrow the thermal tolerance window of marine ectothermal animals. To test this hypothesis, we investigated the effect of an acute temperature rise on energy metabolism of the oyster, Crassostrea gigas chronically exposed to elevated CO2 levels (partial pressure of CO2 in the seawater ~0.15 kPa, seawater pH ~ 7.7. Within one month of incubation at elevated PCO2 and 15 °C hemolymph pH fell (pHe = 7.1 ± 0.2 (CO2-group vs. 7.6 ± 0.1 (control and PeCO2 values in hemolymph increased (0.5 ± 0.2 kPa (CO2-group vs. 0.2 ± 0.04 kPa (control. Slightly but significantly elevated bicarbonate concentrations in the hemolymph of CO2-incubated oysters ([HCO-3]e = 1.8 ± 0.3 mM (CO2-group vs. 1.3 ± 0.1 mM (control indicate only minimal regulation of extracellular acid-base status. At the acclimation temperature of 15 °C the OA-induced decrease in pHe did not lead to metabolic depression in oysters as standard metabolism rates (SMR of CO2-exposed oysters were similar to controls. Upon acute warming SMR rose in both groups, but displayed a stronger increase in the CO2-incubated group. Investigation in isolated gill cells revealed a similar temperature-dependence of respiration between groups. Furthermore, the fraction of cellular energy demand for ion regulation via Na+/K+-ATPase was not affected by chronic hypercapnia or temperature. Metabolic profiling using 1H-NMR spectroscopy revealed substantial changes in some tissues following OA exposure at 15 °C. In mantle tissue alanine and ATP levels decreased significantly whereas an increase in succinate levels was observed in gill tissue. These findings suggest shifts in metabolic pathways following OA-exposure. Our study confirms that OA affects energy metabolism in oysters and

  20. Dietary Energy Source in Dairy Cows in Early Lactation: Metabolites and Metabolic Hormones

    NARCIS (Netherlands)

    Knegsel, van A.T.M.; Brand, van den H.; Graat, E.A.M.; Dijkstra, J.; Jorritsma, R.; Decuypere, M.P.; Tamminga, S.; Kemp, B.

    2007-01-01

    Negative energy balance-related metabolic disorders suggest that the balance between available lipogenic and glucogenic nutrients is important. The objectives of this study were to compare the effects of a glucogenic or a lipogenic diet on liver triacylglycerides (TAG), metabolites, and metabolic ho

  1. Teaching Energy Metabolism Using Scientific Articles: Implementation of a Virtual Learning Environment for Medical Students

    Science.gov (United States)

    de Espindola, Marina Bazzo; El-Bacha, Tatiana; Giannella, Tais Rabetti; Struchiner, Miriam; da Silva, Wagner S.; Da Poian, Andrea T.

    2010-01-01

    This work describes the use of a virtual learning environment (VLE) applied to the biochemistry class for undergraduate, first-year medical students at the Federal University of Rio de Janeiro. The course focused on the integration of energy metabolism, exploring metabolic adaptations in different physiological or pathological states such as…

  2. Energy metabolism and hematology of white-tailed deer fawns

    Science.gov (United States)

    Rawson, R.E.; DelGiudice, G.D.; Dziuk, H.E.; Mech, L.D.

    1992-01-01

    Resting metabolic rates, weight gains and hematologic profiles of six newborn, captive white-tailed deer (Odocoileus virginianus) fawns (four females, two males) were determined during the first 3 mo of life. Estimated mean daily weight gain of fawns was 0.2 kg. The regression equation for metabolic rate was: Metabolic rate (kcal/kg0.75/day) = 56.1 +/- 1.3 (age in days), r = 0.65, P less than 0.001). Regression equations were also used to relate age to red blood cell count (RBC), hemoglobin concentration (Hb), packed cell volume, white blood cell count, mean corpuscular volume, mean corpuscular hemoglobin concentration (MCHC), and mean corpuscular hemoglobin. The age relationships of Hb, MCHC, and smaller RBC's were indicative of an increasing and more efficient oxygen-carrying and exchange capacity to fulfill the increasing metabolic demands for oxygen associated with increasing body size.

  3. Fatty acids from diet and microbiota regulate energy metabolism

    OpenAIRE

    Joe Alcock; Lin, Henry C.

    2015-01-01

    A high-fat diet and elevated levels of free fatty acids are known risk factors for metabolic syndrome, insulin resistance, and visceral obesity. Although these disease associations are well established, it is unclear how different dietary fats change the risk of insulin resistance and metabolic syndrome. Here, we review emerging evidence that insulin resistance and fat storage are linked to changes in the gut microbiota. The gut microbiota and intestinal barrier function, in turn, are highly ...

  4. Regulation of hepatic energy metabolism by the nuclear receptor PXR.

    Science.gov (United States)

    Hakkola, Jukka; Rysä, Jaana; Hukkanen, Janne

    2016-09-01

    The pregnane X receptor (PXR) is a nuclear receptor that is traditionally thought to be specialized for sensing xenobiotic exposure. In concurrence with this feature PXR was originally identified to regulate drug-metabolizing enzymes and transporters. During the last ten years it has become clear that PXR harbors broader functions. Evidence obtained both in experimental animals and humans indicate that ligand-activated PXR regulates hepatic glucose and lipid metabolism and affects whole body metabolic homeostasis. Currently, the consequences of PXR activation on overall metabolic health are not yet fully understood and varying results on the effect of PXR activation or knockout on metabolic disorders and weight gain have been published in mouse models. Rifampicin and St. John's wort, the prototypical human PXR agonists, impair glucose tolerance in healthy volunteers. Chronic exposure to PXR agonists could potentially represent a risk factor for diabetes and metabolic syndrome. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie. PMID:27041449

  5. Regulation of hepatic energy metabolism by the nuclear receptor PXR.

    Science.gov (United States)

    Hakkola, Jukka; Rysä, Jaana; Hukkanen, Janne

    2016-09-01

    The pregnane X receptor (PXR) is a nuclear receptor that is traditionally thought to be specialized for sensing xenobiotic exposure. In concurrence with this feature PXR was originally identified to regulate drug-metabolizing enzymes and transporters. During the last ten years it has become clear that PXR harbors broader functions. Evidence obtained both in experimental animals and humans indicate that ligand-activated PXR regulates hepatic glucose and lipid metabolism and affects whole body metabolic homeostasis. Currently, the consequences of PXR activation on overall metabolic health are not yet fully understood and varying results on the effect of PXR activation or knockout on metabolic disorders and weight gain have been published in mouse models. Rifampicin and St. John's wort, the prototypical human PXR agonists, impair glucose tolerance in healthy volunteers. Chronic exposure to PXR agonists could potentially represent a risk factor for diabetes and metabolic syndrome. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie.

  6. Anaerobic thermophiles.

    Science.gov (United States)

    Canganella, Francesco; Wiegel, Juergen

    2014-01-01

    The term "extremophile" was introduced to describe any organism capable of living and growing under extreme conditions. With the further development of studies on microbial ecology and taxonomy, a variety of "extreme" environments have been found and an increasing number of extremophiles are being described. Extremophiles have also been investigated as far as regarding the search for life on other planets and even evaluating the hypothesis that life on Earth originally came from space. The first extreme environments to be largely investigated were those characterized by elevated temperatures. The naturally "hot environments" on Earth range from solar heated surface soils and water with temperatures up to 65 °C, subterranean sites such as oil reserves and terrestrial geothermal with temperatures ranging from slightly above ambient to above 100 °C, to submarine hydrothermal systems with temperatures exceeding 300 °C. There are also human-made environments with elevated temperatures such as compost piles, slag heaps, industrial processes and water heaters. Thermophilic anaerobic microorganisms have been known for a long time, but scientists have often resisted the belief that some organisms do not only survive at high temperatures, but actually thrive under those hot conditions. They are perhaps one of the most interesting varieties of extremophilic organisms. These microorganisms can thrive at temperatures over 50 °C and, based on their optimal temperature, anaerobic thermophiles can be subdivided into three main groups: thermophiles with an optimal temperature between 50 °C and 64 °C and a maximum at 70 °C, extreme thermophiles with an optimal temperature between 65 °C and 80 °C, and finally hyperthermophiles with an optimal temperature above 80 °C and a maximum above 90 °C. The finding of novel extremely thermophilic and hyperthermophilic anaerobic bacteria in recent years, and the fact that a large fraction of them belong to the Archaea has definitely

  7. Anaerobic Thermophiles

    Directory of Open Access Journals (Sweden)

    Francesco Canganella

    2014-02-01

    Full Text Available The term “extremophile” was introduced to describe any organism capable of living and growing under extreme conditions. With the further development of studies on microbial ecology and taxonomy, a variety of “extreme” environments have been found and an increasing number of extremophiles are being described. Extremophiles have also been investigated as far as regarding the search for life on other planets and even evaluating the hypothesis that life on Earth originally came from space. The first extreme environments to be largely investigated were those characterized by elevated temperatures. The naturally “hot environments” on Earth range from solar heated surface soils and water with temperatures up to 65 °C, subterranean sites such as oil reserves and terrestrial geothermal with temperatures ranging from slightly above ambient to above 100 °C, to submarine hydrothermal systems with temperatures exceeding 300 °C. There are also human-made environments with elevated temperatures such as compost piles, slag heaps, industrial processes and water heaters. Thermophilic anaerobic microorganisms have been known for a long time, but scientists have often resisted the belief that some organisms do not only survive at high temperatures, but actually thrive under those hot conditions. They are perhaps one of the most interesting varieties of extremophilic organisms. These microorganisms can thrive at temperatures over 50 °C and, based on their optimal temperature, anaerobic thermophiles can be subdivided into three main groups: thermophiles with an optimal temperature between 50 °C and 64 °C and a maximum at 70 °C, extreme thermophiles with an optimal temperature between 65 °C and 80 °C, and finally hyperthermophiles with an optimal temperature above 80 °C and a maximum above 90 °C. The finding of novel extremely thermophilic and hyperthermophilic anaerobic bacteria in recent years, and the fact that a large fraction of them belong

  8. Anaerobic treatment as a core technology for energy, nutrients and water from source-separated domestic waste(water)

    NARCIS (Netherlands)

    Zeeman, G.; Kujawa, K.; Mes, de T.Z.D.; Graaff, de M.S.; Abu-Ghunmi, L.N.A.H.; Mels, A.R.; Meulman, B.; Temmink, B.G.; Buisman, C.J.N.; Lier, van J.B.; Lettinga, G.

    2008-01-01

    Based on results of pilot scale research with source-separated black water (BW) and grey water (GW), a new sanitation concept is proposed. BW and GW are both treated in a UASB (-septic tank) for recovery of CH4 gas. Kitchen waste is added to the anaerobic BW treatment for doubling the biogas product

  9. Bio-energy conversion performance, biodegradability, and kinetic analysis of different fruit residues during discontinuous anaerobic digestion.

    Science.gov (United States)

    Zhao, Chen; Yan, Hu; Liu, Yan; Huang, Yan; Zhang, Ruihong; Chen, Chang; Liu, Guangqing

    2016-06-01

    Huge amounts of fruit residues are produced and abandoned annually. The high moisture and organic contents of these residues makes them a big problem to the environment. Conversely, they are a potential resource to the world. Anaerobic digestion is a good way to utilize these organic wastes. In this study, the biomethane conversion performances of a large number of fruit residues were determined and compared using batch anaerobic digestion, a reliable and easily accessible method. The results showed that some fruit residues containing high contents of lipids and carbohydrates, such as loquat peels and rambutan seeds, were well fit for anaerobic digestion. Contrarily, residues with high lignin content were strongly recommended not to be used as a single substrate for methane production. Multiple linear regression model was adopted to simulate the correlation between the organic component of these fruit residues and their experimental methane yield, through which the experimental methane yield could probably be predicted for any other fruit residues. Four kinetic models were used to predict the batch anaerobic digestion process of different fruit residues. It was shown that the modified Gompertz and Cone models were better fit for the fruit residues compared to the first-order and Fitzhugh models. The first findings of this study could provide useful reference and guidance for future studies regarding the applications and potential utilization of fruit residues. PMID:27039123

  10. Energy production from distillery wastewater using single and double-phase upflow anaerobic sludge blanket (UASB) reactor

    Energy Technology Data Exchange (ETDEWEB)

    Muyodi, F.J.; Rubindamayugi, M.S.T. [Univ. of Dar es Salaam, Applied Microbiology Unit (Tanzania, United Republic of)

    1997-12-31

    A Single-phase (SP) and Double-phase (DP) Upflow Anaerobic Sludge Blanket (UASB) reactors treating distillery wastewater were operated in parallel. The DP UASB reactor showed better performance than the SP UASB reactor in terms of maximum methane production rate, methane content and Chemical Oxygen Demand (COD) removal efficiency. (au) 20 refs.

  11. Effect of desipramine and fluoxetine on energy metabolism of cerebral mitochondria.

    Science.gov (United States)

    Villa, Roberto Federico; Ferrari, Federica; Gorini, Antonella; Brunello, Nicoletta; Tascedda, Fabio

    2016-08-25

    Brain bioenergetic abnormalities in mood disorders were detected by neuroimaging in vivo studies in humans. Because of the increasing importance of mitochondrial pathogenetic hypothesis of Depression, in this study the effects of sub-chronic treatment (21days) with desipramine (15mg/kg) and fluoxetine (10mg/kg) were evaluated on brain energy metabolism. On mitochondria in vivo located in neuronal soma (somatic) and on mitochondria of synapses (synaptic), the catalytic activities of regulatory enzymes of mitochondrial energy-yielding metabolic pathways were assayed. Antidepressants in vivo treatment modified the activities of selected enzymes of different mitochondria, leading to metabolic modifications in the energy metabolism of brain cortex: (a) the enhancement of cytochrome oxidase activity on somatic mitochondria; (b) the decrease of malate, succinate dehydrogenase and glutamate-pyruvate transaminase activities of synaptic mitochondria; (c) the selective effect of fluoxetine on enzymes related to glutamate metabolism. These results overcome the conflicting data so far obtained with antidepressants on brain energy metabolism, because the enzymatic analyses were made on mitochondria with diversified neuronal in vivo localization, i.e. on somatic and synaptic. This research is the first investigation on the pharmacodynamics of antidepressants studied at subcellular level, in the perspective of (i) assessing the role of energy metabolism of cerebral mitochondria in animal models of mood disorders, and (ii) highlighting new therapeutical strategies for antidepressants targeting brain bioenergetics. PMID:27268280

  12. 不同等级男子短跑运动员无氧代谢能力特征分析%An Analysis of Features of Anaerobic Metabolism of Male Sprinters of Different Ranks

    Institute of Scientific and Technical Information of China (English)

    刘洋波

    2011-01-01

    为探讨不同等级男子短跑运动员的无氧代谢能力特征.作者对东北师范大学、吉林体育学院及吉林省体工队共22名男子短跑运动员进行了30s Wingate测定(采用MONARK894E功率自行车)。结果表明:不同运动等级男子短跑运动员的无氧代谢能力呈显著差异,即一级运动员总体无氧做功能力强于二级运动员,其中值得注意的是相对最大功率较绝对最大功率的差异更为显著;男子一级短跑运动员较二级运动员能在更短时间内迟到自身无氧做功能力的极限,但同时功率下降的速率也高于二级运动员。%To explore the features of anaerobic metabolism of male sprinters of different ranks, the author uses 30s Wingate method to appraise 22 male sprinters from Northeast Normal University, Jilin Institute of Physical Education, and Sports Team of Jilin province. The findings are as follows: the features of anaerobic metabolism of male sprinters of different ranks are apparently different, viz., male sprinters of first rank are better than the second-rate sprinters; besides, what should be mentioned is that: the relative maximum power and absolute power are much more different, namely, male sprinters with the first rate can reach the limit of anaerobic capacity within shorter time than those with the second rate, but drops more dl~tically.

  13. Dissecting the energy metabolism in Mycoplasma pneumoniae through genome-scale metabolic modeling

    NARCIS (Netherlands)

    Wodke, J.A.; Puchalka, J.; Lluch-Senar, M.; Marcos, J.; Yus, E.; Godinho, M.; Gutierrez-Gallego, R.; Martins Dos Santos, V.A.P.; Serrano, L.; Klipp, E.; Maier, T.

    2013-01-01

    Mycoplasma pneumoniae, a threatening pathogen with a minimal genome, is a model organism for bacterial systems biology for which substantial experimental information is available. With the goal of understanding the complex interactions underlying its metabolism, we analyzed and characterized the met

  14. The effect of herbs on cerebral energy metabolism in cerebral ischemia-reperfusion mice

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Vascular dementia is one of the most familiar types of senile dementia. Over the past few years, the research on the damage of cerebral tissues after ischemia has become a focus. The factors and mechanism of cerebral tissue damage after ischemia are very complex. The handicap of energy metabolism is regarded as the beginning factor which leads to the damage of neurons, but its dynamic changes in ischemic area and its role during the process of neuronal damage are not very clear. There are few civil reports on using 31 P nuclear magnetic resonance instrument to explore the changes of cerebral energy metabolism in intravital animals. After exploring the influence of herbs on cerebral energy metabolism in ischemia-reperfusion mice, we came to the conclusion that herbs can improve the cerebral energy metabolism in ischemia-reperfusion mice.

  15. Thyroid hormones correlate with resting metabolic rate, not daily energy expenditure, in two charadriiform seabirds

    Directory of Open Access Journals (Sweden)

    Kyle H. Elliott

    2013-04-01

    Thyroid hormones affect in vitro metabolic intensity, increase basal metabolic rate (BMR in the lab, and are sometimes correlated with basal and/or resting metabolic rate (RMR in a field environment. Given the difficulty of measuring metabolic rate in the field—and the likelihood that capture and long-term restraint necessary to measure metabolic rate in the field jeopardizes other measurements—we examined the possibility that circulating thyroid hormone levels were correlated with RMR in two free-ranging bird species with high levels of energy expenditure (the black-legged kittiwake, Rissa tridactyla, and thick-billed murre, Uria lomvia. Because BMR and daily energy expenditure (DEE are purported to be linked, we also tested for a correlation between thyroid hormones and DEE. We examined the relationships between free and bound levels of the thyroid hormones thyroxine (T4 and triiodothyronine (T3 with DEE and with 4-hour long measurements of post-absorptive and thermoneutral resting metabolism (resting metabolic rate; RMR. RMR but not DEE increased with T3 in both species; both metabolic rates were independent of T4. T3 and T4 were not correlated with one another. DEE correlated with body mass in kittiwakes but not in murres, presumably owing to the larger coefficient of variation in body mass during chick rearing for the more sexually dimorphic kittiwakes. We suggest T3 provides a good proxy for resting metabolism but not DEE in these seabird species.

  16. Transcriptional Factors Mediating Retinoic Acid Signals in the Control of Energy Metabolism

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    2015-06-01

    Full Text Available Retinoic acid (RA, an active metabolite of vitamin A (VA, is important for many physiological processes including energy metabolism. This is mainly achieved through RA-regulated gene expression in metabolically active cells. RA regulates gene expression mainly through the activation of two subfamilies in the nuclear receptor superfamily, retinoic acid receptors (RARs and retinoid X receptors (RXRs. RAR/RXR heterodimers or RXR/RXR homodimers bind to RA response element in the promoters of RA target genes and regulate their expressions upon ligand binding. The development of metabolic diseases such as obesity and type 2 diabetes is often associated with profound changes in the expressions of genes involved in glucose and lipid metabolism in metabolically active cells. RA regulates some of these gene expressions. Recently, in vivo and in vitro studies have demonstrated that status and metabolism of VA regulate macronutrient metabolism. Some studies have shown that, in addition to RARs and RXRs, hepatocyte nuclear factor 4α, chicken ovalbumin upstream promoter-transcription factor II, and peroxisome proliferator activated receptor β/δ may function as transcriptional factors mediating RA response. Herein, we summarize current progresses regarding the VA metabolism and the role of nuclear receptors in mediating RA signals, with an emphasis on their implication in energy metabolism.

  17. Carnosine: can understanding its actions on energy metabolism and protein homeostasis inform its therapeutic potential?

    OpenAIRE

    Hipkiss, Alan R; Cartwright, Stephanie P.; Bromley, Clare; Gross, Stephane R.; Bill, Roslyn M.

    2013-01-01

    The dipeptide carnosine (β-alanyl-L-histidine) has contrasting but beneficial effects on cellular activity. It delays cellular senescence and rejuvenates cultured senescent mammalian cells. However, it also inhibits the growth of cultured tumour cells. Based on studies in several organisms, we speculate that carnosine exerts these apparently opposing actions by affecting energy metabolism and/or protein homeostasis (proteostasis). Specific effects on energy metabolism include the dipeptide’s ...

  18. Metabolic energy is required in human platelets at any stage during optical aggregation and secretion

    NARCIS (Netherlands)

    Akkerman, Jan Willem N.; Verhoeven, A.J.M.; Mommersteeg, M.E.

    1984-01-01

    The relationship between metabolic energy and platelet aggregation and secretion was investigated by sudden exhaustion of the cell energy content after these platelet responses had been initiated. In normal platelets, optical aggregation was at any stage susceptible to energy exhaustion, whereas sin

  19. The Central Carbon and Energy Metabolism of Marine Diatoms

    Directory of Open Access Journals (Sweden)

    Adriano Nunes-Nesi

    2013-05-01

    Full Text Available Diatoms are heterokont algae derived from a secondary symbiotic event in which a eukaryotic host cell acquired an eukaryotic red alga as plastid. The multiple endosymbiosis and horizontal gene transfer processes provide diatoms unusual opportunities for gene mixing to establish distinctive biosynthetic pathways and metabolic control structures. Diatoms are also known to have significant impact on global ecosystems as one of the most dominant phytoplankton species in the contemporary ocean. As such their metabolism and growth regulating factors have been of particular interest for many years. The publication of the genomic sequences of two independent species of diatoms and the advent of an enhanced experimental toolbox for molecular biological investigations have afforded far greater opportunities than were previously apparent for these species and re-invigorated studies regarding the central carbon metabolism of diatoms. In this review we discuss distinctive features of the central carbon metabolism of diatoms and its response to forthcoming environmental changes and recent advances facilitating the possibility of industrial use of diatoms for oil production. Although the operation and importance of several key pathways of diatom metabolism have already been demonstrated and determined, we will also highlight other potentially important pathways wherein this has yet to be achieved.

  20. Giant cane (Arundo donax L.) can substitute traditional energy crops in producing energy by anaerobic digestion, reducing surface area and costs: A full-scale approach.

    Science.gov (United States)

    Corno, Luca; Lonati, Samuele; Riva, Carlo; Pilu, Roberto; Adani, Fabrizio

    2016-10-01

    Arundo donax L. (Giant cane) was used in a full-scale anaerobic digester (AD) plant (power of 380kWhEE) in partial substitution for corn to produce biogas and electricity. Corn substitution was made on a biomethane potential (BMP) basis so that A. donax L. after substitution accounted for 15.6% of the total mix-BMP (BMPmix) and corn for 66.6% BMPmix. Results obtained indicated that Giant cane was able to substitute for corn, reducing both biomass and electricity production costs, because of both higher biomass productivity (Mg total solid Ha(-1)) and lower biomass cost (€Ha(-1)). Total electricity biogas costs were reduced by 5.5%. The total biomass cost, the total surface area needed to produce the energy crop and the total cost of producing electricity can be reduced by 75.5%, 36.6% and 22%, by substituting corn completely with Giant cane in the mix fed to the full-scale plant.

  1. Giant cane (Arundo donax L.) can substitute traditional energy crops in producing energy by anaerobic digestion, reducing surface area and costs: A full-scale approach.

    Science.gov (United States)

    Corno, Luca; Lonati, Samuele; Riva, Carlo; Pilu, Roberto; Adani, Fabrizio

    2016-10-01

    Arundo donax L. (Giant cane) was used in a full-scale anaerobic digester (AD) plant (power of 380kWhEE) in partial substitution for corn to produce biogas and electricity. Corn substitution was made on a biomethane potential (BMP) basis so that A. donax L. after substitution accounted for 15.6% of the total mix-BMP (BMPmix) and corn for 66.6% BMPmix. Results obtained indicated that Giant cane was able to substitute for corn, reducing both biomass and electricity production costs, because of both higher biomass productivity (Mg total solid Ha(-1)) and lower biomass cost (€Ha(-1)). Total electricity biogas costs were reduced by 5.5%. The total biomass cost, the total surface area needed to produce the energy crop and the total cost of producing electricity can be reduced by 75.5%, 36.6% and 22%, by substituting corn completely with Giant cane in the mix fed to the full-scale plant. PMID:27428299

  2. Instrumentation in anaerobic treatment - research and practice

    NARCIS (Netherlands)

    Spanjers, H.; Lier, van J.B.

    2006-01-01

    High rate anaerobic treatment reactors are able to uncouple solids and liquid retention time, resulting in high biomass concentrations. Principal advantages of anaerobic treatment include: energy efficiency, low biomass yield, low nutrient requirement and high volumetric organic loadings. In order t

  3. Comparing environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy--a life cycle perspective.

    Science.gov (United States)

    De Vries, J W; Vinken, T M W J; Hamelin, L; De Boer, I J M

    2012-12-01

    The aim of this work was to assess the environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy, from a life cycle perspective. This included assessing environmental impacts and land use change emissions (LUC) required to replace used co-substrates for anaerobic digestion. Environmental impact categories considered were climate change, terrestrial acidification, marine and freshwater eutrophication, particulate matter formation, land use, and fossil fuel depletion. Six scenarios were evaluated: mono-digestion of manure, co-digestion with: maize silage, maize silage and glycerin, beet tails, wheat yeast concentrate (WYC), and roadside grass. Mono-digestion reduced most impacts, but represented a limited source for bio-energy. Co-digestion with maize silage, beet tails, and WYC (competing with animal feed), and glycerin increased bio-energy production (up to 568%), but at expense of increasing climate change (through LUC), marine eutrophication, and land use. Co-digestion with wastes or residues like roadside grass gave the best environmental performance. PMID:23026340

  4. Benzoyl-coenzyme A reductase (dearomatizing), a key enzyme of anaerobic aromatic metabolism. ATP dependence of the reaction, purification and some properties of the enzyme from Thauera aromatica strain K172.

    Science.gov (United States)

    Boll, M; Fuchs, G

    1995-12-15

    Anoxic metabolism of many aromatic compounds proceeds via the common intermediate benzoyl-CoA. Benzoyl-CoA is dearomatized by benzoyl-CoA reductase (dearomatizing) in a two-electron reduction step, possibly yielding cyclohex-1,5-diene-1-carboxyl-CoA. This process has to overcome a high activation energy and is considered a biological Birch reduction. The central, aromatic-ring-reducing enzyme was investigated for the first time in the denitrifying bacterium Thauera aromatica strain K172. A spectrophotometric assay was developed which was strictly dependent on MgATP, both with cell extract and with purified enzyme. The oxygen-sensitive new enzyme was purified 35-fold with 20% yield under anaerobic conditions in the presence of 0.25 mM dithionite. It had a native molecular mass of approximately 170 kDa and consisted of four subunits a,b,c,d of 48, 45, 38 and 32 kDa. The oligomer composition of the protein most likely is abcd. The ultraviolet/visible spectrum of the protein as isolated, but without dithionite, was characteristic for an iron-sulfur protein with an absorption maximum at 279 nm and a broad shoulder at 390 nm. The estimated molar absorption coefficient at 390 nm was 35,000 M-1 cm-1. Reduction of the enzyme by dithionite resulted in a decrease of absorbance at 390 nm, and the colour turned from greenish-brown to red-brown. The enzyme contained 10.8 +/- 1.5 mol Fe and 10.5 +/- 1.5 mol acid-labile sulfur/mol. Besides zinc (0.5 mol/mol protein) no other metals nor selenium could be detected in significant amounts. The enzyme preparation contained a flavin or flavin-like compound; the estimated content was 0.3 mol/mol enzyme. The enzyme reaction required MgATP and a strong reductant such as Ti(III). The reaction catalyzed is: benzoyl-CoA + 2 Ti(III) + n ATP-->non-aromatic acyl-CoA + 2 Ti(IV) + n ADP + n Pi. The estimated number n of ATP molecules hydrolyzed/two electrons transferred in benzoyl-CoA reduction is 2-4. In the absence of benzoyl-CoA the enzyme

  5. EBPR using crude glycerol: assessing process resiliency and exploring metabolic anomalies.

    Science.gov (United States)

    Coats, Erik R; Dobroth, Zachary T; Brinkman, Cynthia K

    2015-01-01

    Enhanced biological phosphorus removal (EBPR) is predicated on exposing bacteria to cyclical anaerobic/aerobic environments while providing volatile fatty acids (VFAs). Combined, this environment enriches for phosphorus accumulating organisms (PAOs) and induces metabolisms to ensure excess phosphorus removal. Crude glycerol (CG), a byproduct of biodiesel manufacturing, is an alternate waste stream that could be substituted to achieve excess phosphorus removal; research into the use of CG yielded unexpected findings. While CG was an excellent substrate to accomplish and/or help achieve excess phosphorus removal, CG-fed bacteria did not consistently exhibit theoretical EBPR metabolisms. Specifically, anaerobic phosphorus release was not required for successful EBPR; however, carbon cycling patterns were consistent with theory. Analysis of results suggests that PAOs will first leverage carbon to generate energy anaerobically; only as needed will the bacteria utilize polyphosphate reserves anaerobically. Results also demonstrated that excess phosphorus removal can be achieved with a small fraction of PAOs. PMID:25630129

  6. Association between shortage of energy supply and nuclear gene mutations leading to carcinomatous transformation

    OpenAIRE

    DU, JIANPING

    2015-01-01

    Anaerobic bacteria use glycolysis, an oxygen-independent metabolic pathway, whereas energy metabolism in the evolved eukaryotic cell is performed via oxidative phosphorylation, with all eukaryotic cell activities depending upon high energy consumption. However, in cancer cells evolving from eukaryotic cells, the energy metabolism switches from oxidative phosphorylation to glycolysis. The shortage of energy supply induces cancer cells to acquire specific characteristics. Base pair renewal is t...

  7. Potential application of anaerobic extremophiles for hydrogen production

    Science.gov (United States)

    Pikuta, Elena V.; Hoover, Richard B.

    2004-11-01

    In processes of the substrate fermentation most anaerobes produce molecular hydrogen as a waste end product, which often controls the culture growth as an inhibitor. Usually in nature the hydrogen is easily removed from an ecosystem, due to its physical features, and an immediate consumption by the secondary anaerobes that sometimes behave as competitors for electron donors; a classical example of this kind of substrate competition in anaerobic microbial communities is the interaction between methanogens and sulfate- or sulfur-reducers. Previously, on the mixed cultures of anaerobes at neutral pH, it was demonstrated that bacterial hydrogen production could provide a good alternative energy source. At neutral pH the original cultures could easily contaminated by methanogens, and the most unpleasant side effect of these conditions is the development of pathogenic bacteria. In both cases the rate of hydrogen production was dramatically decreased since some part of the hydrogen was transformed to methane, and furthermore, the cultivation with pathogenic contaminants on an industrial scale would create an unsafe situation. In our laboratory the experiments with obligately alkaliphilic bacteria producing hydrogen as an end metabolic product were performed at different conditions. The mesophilic, haloalkaliphilic and obligately anaerobic bacterium Spirochaeta americana ASpG1T was studied and various cultivation regimes were compared for the most effective hydrogen production. In a highly mineralized media with pH 9.5-10.0 not many known methanogens are capable of growth, and the probability of developing pathogenic contaminants is theoretically is close to zero (in medicine carbonate- saturated solutions are applied as antiseptics). Therefore the cultivation of alkaliphilic hydrogen producing bacteria could be considered as a safe and economical process for large-scale industrial bio-hydrogen production in the future. Here we present and discuss the experimental data

  8. Natural compounds regulate energy metabolism by the modulating the activity of lipid-sensing nuclear receptors.

    Science.gov (United States)

    Goto, Tsuyoshi; Kim, Young-Il; Takahashi, Nobuyuki; Kawada, Teruo

    2013-01-01

    Obesity causes excess fat accumulation in various tissues, most notoriously in the adipose tissue, along with other insulin-responsive organs such as skeletal muscle and the liver, which predisposes an individual to the development of metabolic abnormalities. The molecular mechanisms underlying obesity-induced metabolic abnormalities have not been completely elucidated; however, in recent years, the search for therapies to prevent the development of obesity and obesity-associated metabolic disorders has increased. It is known that several nuclear receptors, when activated by specific ligands, regulate carbohydrate and lipid metabolism at the transcriptional level. The expression of lipid metabolism-related enzymes is directly regulated by the activity of various nuclear receptors via their interaction with specific response elements in promoters of those genes. Many natural compounds act as ligands of nuclear receptors and regulate carbohydrate and lipid metabolism by regulating the activities of these nuclear receptors. In this review, we describe our current knowledge of obesity, the role of lipid-sensing nuclear receptors in energy metabolism, and several examples of food factors that act as agonists or antagonists of nuclear receptors, which may be useful for the management of obesity and the accompanying energy metabolism abnormalities.

  9. Sex Differences in Energy Metabolism Need to Be Considered with Lifestyle Modifications in Humans

    Directory of Open Access Journals (Sweden)

    Betty N. Wu

    2011-01-01

    Full Text Available Women have a higher proportion of body fat compared to men. However, women consume fewer kilojoules per kilogram lean mass and burn fat more preferentially during exercise compared with men. During gestation, women store even greater amounts of fat that cannot be solely attributed to increased energy intake. These observations suggest that the relationship between kilojoules consumed and kilojoules utilised is different in men and women. The reason for these sex differences in energy metabolism is not known; however, it may relate to sex steroids, differences in insulin resistance, or metabolic effects of other hormones such as leptin. When considering lifestyle modifications, sex differences in energy metabolism should be considered. Moreover, elucidating the regulatory role of hormones in energy homeostasis is important for understanding the pathogenesis of obesity and perhaps in the future may lead to ways to reduce body fat with less energy restriction.

  10. The Influence of Hydration on Anaerobic Performance: A Review

    Science.gov (United States)

    Kraft, Justin A.; Green, James M.; Bishop, Phillip A.; Richardson, Mark T.; Neggers, Yasmin H.; Leeper, James D.

    2012-01-01

    This review examines the influence of dehydration on muscular strength and endurance and on single and repeated anaerobic sprint bouts. Describing hydration effects on anaerobic performance is difficult because various exercise modes are dominated by anaerobic energy pathways, but still contain inherent physiological differences. The critical…

  11. Ontogeny of hepatic energy metabolism genes in mice as revealed by RNA-sequencing.

    Science.gov (United States)

    Renaud, Helen J; Cui, Yue Julia; Lu, Hong; Zhong, Xiao-bo; Klaassen, Curtis D

    2014-01-01

    The liver plays a central role in metabolic homeostasis by coordinating synthesis, storage, breakdown, and redistribution of nutrients. Hepatic energy metabolism is dynamically regulated throughout different life stages due to different demands for energy during growth and development. However, changes in gene expression patterns throughout ontogeny for factors important in hepatic energy metabolism are not well understood. We performed detailed transcript analysis of energy metabolism genes during various stages of liver development in mice. Livers from male C57BL/6J mice were collected at twelve ages, including perinatal and postnatal time points (n = 3/age). The mRNA was quantified by RNA-Sequencing, with transcript abundance estimated by Cufflinks. One thousand sixty energy metabolism genes were examined; 794 were above detection, of which 627 were significantly changed during at least one developmental age compared to adult liver. Two-way hierarchical clustering revealed three major clusters dependent on age: GD17.5-Day 5 (perinatal-enriched), Day 10-Day 20 (pre-weaning-enriched), and Day 25-Day 60 (adolescence/adulthood-enriched). Clustering analysis of cumulative mRNA expression values for individual pathways of energy metabolism revealed three patterns of enrichment: glycolysis, ketogenesis, and glycogenesis were all perinatally-enriched; glycogenolysis was the only pathway enriched during pre-weaning ages; whereas lipid droplet metabolism, cholesterol and bile acid metabolism, gluconeogenesis, and lipid metabolism were all enriched in adolescence/adulthood. This study reveals novel findings such as the divergent expression of the fatty acid β-oxidation enzymes Acyl-CoA oxidase 1 and Carnitine palmitoyltransferase 1a, indicating a switch from mitochondrial to peroxisomal β-oxidation after weaning; as well as the dynamic ontogeny of genes implicated in obesity such as Stearoyl-CoA desaturase 1 and Elongation of very long chain fatty acids-like 3. These

  12. Ontogeny of hepatic energy metabolism genes in mice as revealed by RNA-sequencing.

    Directory of Open Access Journals (Sweden)

    Helen J Renaud

    Full Text Available The liver plays a central role in metabolic homeostasis by coordinating synthesis, storage, breakdown, and redistribution of nutrients. Hepatic energy metabolism is dynamically regulated throughout different life stages due to different demands for energy during growth and development. However, changes in gene expression patterns throughout ontogeny for factors important in hepatic energy metabolism are not well understood. We performed detailed transcript analysis of energy metabolism genes during various stages of liver development in mice. Livers from male C57BL/6J mice were collected at twelve ages, including perinatal and postnatal time points (n = 3/age. The mRNA was quantified by RNA-Sequencing, with transcript abundance estimated by Cufflinks. One thousand sixty energy metabolism genes were examined; 794 were above detection, of which 627 were significantly changed during at least one developmental age compared to adult liver. Two-way hierarchical clustering revealed three major clusters dependent on age: GD17.5-Day 5 (perinatal-enriched, Day 10-Day 20 (pre-weaning-enriched, and Day 25-Day 60 (adolescence/adulthood-enriched. Clustering analysis of cumulative mRNA expression values for individual pathways of energy metabolism revealed three patterns of enrichment: glycolysis, ketogenesis, and glycogenesis were all perinatally-enriched; glycogenolysis was the only pathway enriched during pre-weaning ages; whereas lipid droplet metabolism, cholesterol and bile acid metabolism, gluconeogenesis, and lipid metabolism were all enriched in adolescence/adulthood. This study reveals novel findings such as the divergent expression of the fatty acid β-oxidation enzymes Acyl-CoA oxidase 1 and Carnitine palmitoyltransferase 1a, indicating a switch from mitochondrial to peroxisomal β-oxidation after weaning; as well as the dynamic ontogeny of genes implicated in obesity such as Stearoyl-CoA desaturase 1 and Elongation of very long chain fatty

  13. Startup and stabilization of anaerobic membrane bioreactors at ambient temperature

    OpenAIRE

    Benito Peña, Carlos

    2015-01-01

    There has been an increasing interest in wastewater treatment in last decades to reduce human footprint. Primarily, anaerobic technology focused on treatment and stabilization of sludge, but now the tendency is to give it a major role in low cost treatment of high/low strength wastewaters, since anaerobic digestion offers energy generation through gas production. Anaerobic membrane bioreactors (AnMBR) combine anaerobic digestion with membrane filtration. They are becoming a feasible opti...

  14. Harvesting biomechanical energy or carrying batteries? An evaluation method based on a comparison of metabolic power

    OpenAIRE

    Schertzer, Eliran; Riemer, Raziel

    2015-01-01

    Background Harvesting energy from human motion is an innovative alternative to using batteries as a source of electrical power for portable devices. Yet there are no guidelines as to whether energy harvesting should be preferred over batteries. This paper introduces an approach to determine which source of energy should be preferred. The proposed approach compares the metabolic power while harvesting energy and while using batteries (or any other power supply, e.g., solar panels), which provi...

  15. [Optimization of energy metabolism in patients with chronic heart failure].

    Science.gov (United States)

    Korzh, A N

    2010-01-01

    Nowadays particular interest of clinicians is attracted by metabolic therapy of patients with chronic heart failure (CHF). The objective of this study was to investigate the influence of complex therapy with addition of Vasonat on the dynamics of remodeling indexes of left ventricle and functional class of CHF on classification of NYHA. It has been shown that application of metabolic modulator Vasonat in addition to conventional therapy of CHF facilitated the clinical improvement and significant decline of functional class. Vasonat use resulted in the meaningful improvement of the contractive function of myocardium and increase of tolerance to the physical exercise. Moreover, high efficiency of Vasonat has been demonstrated in the control of the syndrome of oxidizing stress, by decrease in intensity of free-radical processes and activation of the antioxidant defense system. PMID:21265120

  16. Role of energy metabolism in the brown fat gene program

    OpenAIRE

    Minwoo eNam; Marcus eCooper

    2015-01-01

    In murine and human brown adipose tissue (BAT), mitochondria are powerful generators of heat that safely metabolize fat, a feature that has great promise in the fight against obesity and diabetes. Recent studies suggest that the action of mitochondria extend beyond their conventional role as generators of heat. There is mounting evidence that impaired mitochondrial respiratory capacity is accompanied by attenuated expression of Ucp1 and other BAT-selective genes, implying that mitochondria ex...

  17. Interrelationships between mitochondrial fusion, energy metabolism and oxidative stress during development in Caenorhabditis elegans

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda, Kayo [Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Education and Research Support Center, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Hartman, Philip S. [Biology Department, Texas Christian University, Fort Worth, TX 76129 (United States); Ishii, Takamasa [Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Suda, Hitoshi [School of High-Technology for Human Welfare, Tokai University, Nishino 317, Numazu, Shizuoka 410-0395 (Japan); Akatsuka, Akira [Education and Research Support Center, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Shoyama, Tetsuji [School of High-Technology for Human Welfare, Tokai University, Nishino 317, Numazu, Shizuoka 410-0395 (Japan); Miyazawa, Masaki [Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan); Ishii, Naoaki, E-mail: nishii@is.icc.u-tokai.ac.jp [Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193 (Japan)

    2011-01-21

    Research highlights: {yields} Growth and development of a fzo-1 mutant defective in the fusion process of mitochondria was delayed relative to the wild type of Caenorhabditis elegans. {yields} Oxygen sensitivity during larval development, superoxide production and carbonyl protein accumulation of the fzo-1 mutant were similar to wild type. {yields} fzo-1 animals had significantly lower metabolism than did N2 and mev-1 overproducing superoxide from mitochondrial electron transport complex II. {yields} Mitochondrial fusion can profoundly affect energy metabolism and development. -- Abstract: Mitochondria are known to be dynamic structures with the energetically and enzymatically mediated processes of fusion and fission responsible for maintaining a constant flux. Mitochondria also play a role of reactive oxygen species production as a byproduct of energy metabolism. In the current study, interrelationships between mitochondrial fusion, energy metabolism and oxidative stress on development were explored using a fzo-1 mutant defective in the fusion process and a mev-1 mutant overproducing superoxide from mitochondrial electron transport complex II of Caenorhabditis elegans. While growth and development of both single mutants was slightly delayed relative to the wild type, the fzo-1;mev-1 double mutant experienced considerable delay. Oxygen sensitivity during larval development, superoxide production and carbonyl protein accumulation of the fzo-1 mutant were similar to wild type. fzo-1 animals had significantly lower metabolism than did N2 and mev-1. These data indicate that mitochondrial fusion can profoundly affect energy metabolism and development.

  18. Energy metabolism in intestinal epithelial cells during maturation along the crypt-villus axis

    Science.gov (United States)

    Yang, Huansheng; Wang, Xiaocheng; Xiong, Xia; Yin, Yulong

    2016-01-01

    Intestinal epithelial cells continuously migrate and mature along crypt-villus axis (CVA), while the changes in energy metabolism during maturation are unclear in neonates. The present study was conducted to test the hypothesis that the energy metabolism in intestinal epithelial cells would be changed during maturation along CVA in neonates. Eight 21-day-old suckling piglets were used. Intestinal epithelial cells were isolated sequentially along CVA, and proteomics was used to analyze the changes in proteins expression in epithelial cells along CVA. The identified differentially expressed proteins were mainly involved in cellular process, metabolic process, biological regulation, pigmentation, multicellular organizational process and so on. The energy metabolism in intestinal epithelial cells of piglets was increased from the bottom of crypt to the top of villi. Moreover, the expression of proteins related to the metabolism of glucose, most of amino acids, and fatty acids was increased in intestinal epithelial cells during maturation along CVA, while the expression of proteins related to glutamine metabolism was decreased from crypt to villus tip. The expression of proteins involved in citrate cycle was also increased intestinal epithelial cells during maturation along CVA. Moreover, dietary supplementation with different energy sources had different effects on intestinal structure of weaned piglets. PMID:27558220

  19. Effect of bacterial protein meal on protein and energy metabolism in growing chickens

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Skrede, Anders

    2006-01-01

    This experiment investigates the effect of increasing the dietary content of bacterial protein meal (BPM) on the protein and energy metabolism, and carcass chemical composition of growing chickens. Seventy-two Ross male chickens were allocated to four diets, each in three replicates with 0% (D0), 2...... for protein and energy retention found in the balance and respiration experiments. It was concluded that the overall protein and energy metabolism as well as carcass composition were not influenced by a dietary content of up to 6% BPM corresponding to 20% of dietary N....

  20. Body composition and energy metabolism in elderly people.

    NARCIS (Netherlands)

    Visser, M.

    1995-01-01

    This thesis describes several studies related to the three components of energy balance in elderly people: body composition, energy expenditure, and energy intake.Body composition. The applicability of the body mass index, skinfold thickness method, and multi-frequency bioelectrical impedance was te

  1. Role of gut microbiota in the control of energy and carbohydrate metabolism

    NARCIS (Netherlands)

    Venema, K.

    2010-01-01

    Purpose of review: To describe the recent developments and insights gained in the role played by the colonic microbiota in energy and carbohydrate metabolism related to obesity in humans. Recent findings: Previous findings that the ratio of Firmicutes and Bacteriodetes is important in energy harvest

  2. Simulating the physiology of athletes during endurance sports events: Modelling human energy conversion and metabolism

    NARCIS (Netherlands)

    Beek, J.H.G.M. van; Supandi, F.; Gavai, A.K.; Graaf, A.A. de; Binsl, T.W.; Hettling, H.

    2011-01-01

    The human physiological system is stressed to its limits during endurance sports competition events.We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We calculate

  3. Dietary energy density is associated with obesity and the metabolic syndrome in U.S. adults

    Science.gov (United States)

    Rising obesity rates have been linked to the consumption of energy-dense diets. We examined whether dietary energy density was associated with obesity and related disorders, including insulin resistance and the metabolic syndrome. We conducted a cross-sectional study using nationally representative ...

  4. PET studies of brain energy metabolism in a model of subcortical dementia: progressive supranuclear Palsy

    International Nuclear Information System (INIS)

    In 41 patients with clinically determined Progressive Supranuclear Palsy, a model of degenerative subcortical dementia, alterations in regional brain energy metabolism with respect to control subjects have been investigated using positron computed tomography and correlated to clinical and neuropsychological scores. A generalized significant reduction in brain metabolism was found, which predominated in the prefrontal cortex in accordance with, and statistically correlated to, the frontal neuropsychological score

  5. Thermal effects on cephalopod energy metabolism - A case study for Sepia officinalis

    OpenAIRE

    Mark, F.; Melzner, Frank; Bock, C.; Poermer, H.; Ellington, C.; Claireaux, G.

    2008-01-01

    Cephalopods are the largest, most active invertebrates and there is considerable evidence for their convergent evolution with fishes. However, most active cephalopods display standard and active metabolic rates that are several-fold higher than comparably sized fishes. Shifting habitat temperatures due to climate change will therefore affect a cephalopods energy metabolism much more than that of a fish. Prediction of the probable outcome of cephalopod-fish competition thus requires quantitati...

  6. In vivo modular control analysis of energy metabolism in contracting skeletal muscle

    OpenAIRE

    Arsac, Laurent M; Beuste, Christophe; Miraux, Sylvain; Deschodt-Arsac, Veronique; Thiaudière, Eric; Franconi, Jean-Michel; Diolez, Philippe H

    2008-01-01

    Abstract We used 31P MR spectroscopy measurements of energetic intermediates (ATP, Pi, PCr) in combination with the analytical tools of metabolic control analysis to study in vivo energy metabolism in contracting skeletal muscle of anesthetized rats over a broad range of workload. According to our recent Modular Control Analysis (MoCA) used to describe regulatory mechanisms in beating heart, we defined the energetic system of muscle contraction as two modules (PCr-Producer and PCr-...

  7. SIRT1 IS INVOLVED IN ENERGY METABOLISM: THE ROLE OF CHRONIC ETHANOL FEEDING AND RESVERATROL

    OpenAIRE

    Oliva, Joan; French, Barbara A.; Li, Jun; Bardag-Gorce, Fawzia; Fu, Paul; French, Samuel W.

    2008-01-01

    Sirt1, a deacetylase involved in regulating energy metabolism in response to calorie restriction, is up regulated after chronic ethanol feeding using the intragastric feeding model of alcohol liver disease. PGC1α is also up regulated in response to ethanol. These changes are consistent with activation of the Sirt1/PGC1α pathway of metabolism and aging, involved in alcohol liver disease including steatosis, necrosis and fibrosis of the liver. To test this hypothesis, male rats fed ethanol intr...

  8. Adenylate Kinase and AMP Signaling Networks: Metabolic Monitoring, Signal Communication and Body Energy Sensing

    Directory of Open Access Journals (Sweden)

    Andre Terzic

    2009-04-01

    Full Text Available Adenylate kinase and downstream AMP signaling is an integrated metabolic monitoring system which reads the cellular energy state in order to tune and report signals to metabolic sensors. A network of adenylate kinase isoforms (AK1-AK7 are distributed throughout intracellular compartments, interstitial space and body fluids to regulate energetic and metabolic signaling circuits, securing efficient cell energy economy, signal communication and stress response. The dynamics of adenylate kinase-catalyzed phosphotransfer regulates multiple intracellular and extracellular energy-dependent and nucleotide signaling processes, including excitation-contraction coupling, hormone secretion, cell and ciliary motility, nuclear transport, energetics of cell cycle, DNA synthesis and repair, and developmental programming. Metabolomic analyses indicate that cellular, interstitial and blood AMP levels are potential metabolic signals associated with vital functions including body energy sensing, sleep, hibernation and food intake. Either low or excess AMP signaling has been linked to human disease such as diabetes, obesity and hypertrophic cardiomyopathy. Recent studies indicate that derangements in adenylate kinase-mediated energetic signaling due to mutations in AK1, AK2 or AK7 isoforms are associated with hemolytic anemia, reticular dysgenesis and ciliary dyskinesia. Moreover, hormonal, food and antidiabetic drug actions are frequently coupled to alterations of cellular AMP levels and associated signaling. Thus, by monitoring energy state and generating and distributing AMP metabolic signals adenylate kinase represents a unique hub within the cellular homeostatic network.

  9. Anaerobic digestion of goat manure: bio-conversion of energy and bio fertilizer; Digestao anaerobica de dejetos de caprinos: conversor biologico de energia e biofertilizante

    Energy Technology Data Exchange (ETDEWEB)

    Canafistula, Francisco Jose Firmino; Carvalho, Paulo Cesar Marques de; Teixeira, Adunias dos Santos [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. Engenharia Eletrica], Emails: firmino@ufc.br, carvalho@dee.ufc.br, adunias@ufc.com

    2009-07-01

    This research aims at analyzing biogas produced by anaerobic digestion of goat excrements related to energy generation, in addition to analyzing the bio-fertilizer as a byproduct of the process. Therefore, new products are generated from semi-intensive and extensive of goats, increasing its economical and environmental viability of the activity. The biogas was applied as the fuel for an Otto cycle internal combustion engine of 5.5 HP used to drive a hydraulic pump that supplied water to an area of one hectare of pasture. In addition, the spreadsheet GDER was applied to compute the kWh cost of the following electricity sources: biogas from goat excrement, diesel, electrical grid, wind and solar. It was found tat the biogas can substitute 30% of the daily energy requirements, and one can state that 1 m{sup 3} of biogas is equivalent to 740 mL of gasoline. (author)

  10. Rhodanese functions as sulfur supplier for key enzymes in sulfur energy metabolism.

    Science.gov (United States)

    Aussignargues, Clément; Giuliani, Marie-Cécile; Infossi, Pascale; Lojou, Elisabeth; Guiral, Marianne; Giudici-Orticoni, Marie-Thérèse; Ilbert, Marianne

    2012-06-01

    How microorganisms obtain energy is a challenging topic, and there have been numerous studies on the mechanisms involved. Here, we focus on the energy substrate traffic in the hyperthermophilic bacterium Aquifex aeolicus. This bacterium can use insoluble sulfur as an energy substrate and has an intricate sulfur energy metabolism involving several sulfur-reducing and -oxidizing supercomplexes and enzymes. We demonstrate that the cytoplasmic rhodanese SbdP participates in this sulfur energy metabolism. Rhodaneses are a widespread family of proteins known to transfer sulfur atoms. We show that SbdP has also some unusual characteristics compared with other rhodaneses; it can load a long sulfur chain, and it can interact with more than one partner. Its partners (sulfur reductase and sulfur oxygenase reductase) are key enzymes of the sulfur energy metabolism of A. aeolicus and share the capacity to use long sulfur chains as substrate. We demonstrate a positive effect of SbdP, once loaded with sulfur chains, on sulfur reductase activity, most likely by optimizing substrate uptake. Taken together, these results lead us to propose a physiological role for SbdP as a carrier and sulfur chain donor to these key enzymes, therefore enabling channeling of sulfur substrate in the cell as well as greater efficiency of the sulfur energy metabolism of A. aeolicus. PMID:22496367

  11. Body composition and energy metabolism in elderly people.

    OpenAIRE

    Visser, M.

    1995-01-01

    This thesis describes several studies related to the three components of energy balance in elderly people: body composition, energy expenditure, and energy intake.Body composition. The applicability of the body mass index, skinfold thickness method, and multi-frequency bioelectrical impedance was tested in elderly men and women. The first two methods predicted body fat in elderly people on a group level with a mean prediction error of 5%. The impedance method predicted total body water (at 50...

  12. Energy metabolism and energy-sensing pathways in mammalian embryonic and adult stem cell fate

    OpenAIRE

    Rafalski, Victoria A.; Mancini, Elena; Brunet, Anne

    2012-01-01

    Metabolism is influenced by age, food intake, and conditions such as diabetes and obesity. How do physiological or pathological metabolic changes influence stem cells, which are crucial for tissue homeostasis? This Commentary reviews recent evidence that stem cells have different metabolic demands than differentiated cells, and that the molecular mechanisms that control stem cell self-renewal and differentiation are functionally connected to the metabolic state of the cell and the surrounding...

  13. Altered Metabolic Homeostasis in Amyotrophic Lateral Sclerosis: Mechanisms of Energy Imbalance and Contribution to Disease Progression.

    Science.gov (United States)

    Ioannides, Zara A; Ngo, Shyuan T; Henderson, Robert D; McCombe, Pamela A; Steyn, Frederik J

    2016-01-01

    Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the death of motor neurones, which leads to paralysis and death in an average of 3 years following diagnosis. The cause of ALS is unknown, but there is substantial evidence that metabolic factors, including nutritional state and body weight, affect disease progression and survival. This review provides an overview of the characteristics of metabolic dysregulation in ALS focusing on mechanisms that lead to disrupted energy supply (at a whole-body and cellular level) and altered energy expenditure. We discuss how a decrease in energy supply occurs in parallel with an increase in energy demand and leads to a state of chronic energy deficit which has a negative impact on disease outcome in ALS. We conclude by presenting potential and tested strategies to compensate for, or correct this energy imbalance, and speculate on promising areas for further research. PMID:27400276

  14. Energy metabolism and metabolic sensors in stem cells: the metabostem crossroads of aging and cancer.

    Science.gov (United States)

    Menendez, Javier A; Joven, Jorge

    2014-01-01

    We are as old as our adult stem cells are; therefore, stem cell exhaustion is considered a hallmark of aging. Our tumors are as aggressive as the number of cancer stem cells (CSCs) they bear because CSCs can survive treatments with hormones, radiation, chemotherapy, and molecularly targeted drugs, thus increasing the difficulty of curing cancer. Not surprisingly, interest in stem cell research has never been greater among members of the public, politicians, and scientists. But how can we slow the rate at which our adult stem cells decline over our lifetime, reducing the regenerative potential of tissues, while efficiently eliminating the aberrant, life-threatening activity of "selfish", immortal, and migrating CSCs? Frustrated by the gene-centric limitations of conventional approaches to aging diseases, our group and other groups have begun to appreciate that bioenergetic metabolism, i.e., the production of fuel & building blocks for growth and division, and autophagy/mitophagy, i.e., the quality-control, self-cannibalistic system responsible for "cleaning house" and "recycling the trash", can govern the genetic and epigenetic networks that facilitate stem cell behaviors. Indeed, it is reasonable to suggest the existence of a "metabostem" infrastructure that operates as a shared hallmark of aging and cancer, thus making it physiologically plausible to maintain or even increase the functionality of adult stem cells while reducing the incidence of cancer and extending the lifespan. This "metabostemness" property could lead to the discovery of new drugs that reprogram cell metabotypes to increase the structural and functional integrity of adult stem cells and positively influence their lineage determination, while preventing the development and aberrant function of stem cells in cancer tissues. While it is obvious that the antifungal antibiotic rapamycin, the polyphenol resveratrol, and the biguanide metformin already belong to this new family of metabostemness

  15. Constrained Total Energy Expenditure and Metabolic Adaptation to Physical Activity in Adult Humans.

    Science.gov (United States)

    Pontzer, Herman; Durazo-Arvizu, Ramon; Dugas, Lara R; Plange-Rhule, Jacob; Bovet, Pascal; Forrester, Terrence E; Lambert, Estelle V; Cooper, Richard S; Schoeller, Dale A; Luke, Amy

    2016-02-01

    Current obesity prevention strategies recommend increasing daily physical activity, assuming that increased activity will lead to corresponding increases in total energy expenditure and prevent or reverse energy imbalance and weight gain [1-3]. Such Additive total energy expenditure models are supported by exercise intervention and accelerometry studies reporting positive correlations between physical activity and total energy expenditure [4] but are challenged by ecological studies in humans and other species showing that more active populations do not have higher total energy expenditure [5-8]. Here we tested a Constrained total energy expenditure model, in which total energy expenditure increases with physical activity at low activity levels but plateaus at higher activity levels as the body adapts to maintain total energy expenditure within a narrow range. We compared total energy expenditure, measured using doubly labeled water, against physical activity, measured using accelerometry, for a large (n = 332) sample of adults living in five populations [9]. After adjusting for body size and composition, total energy expenditure was positively correlated with physical activity, but the relationship was markedly stronger over the lower range of physical activity. For subjects in the upper range of physical activity, total energy expenditure plateaued, supporting a Constrained total energy expenditure model. Body fat percentage and activity intensity appear to modulate the metabolic response to physical activity. Models of energy balance employed in public health [1-3] should be revised to better reflect the constrained nature of total energy expenditure and the complex effects of physical activity on metabolic physiology.

  16. Inter-organ metabolic communication involved in energy homeostasis: potential therapeutic targets for obesity and metabolic syndrome.

    Science.gov (United States)

    Yamada, Tetsuya; Oka, Yoshitomo; Katagiri, Hideki

    2008-01-01

    The global rate of obesity is rising alarmingly, exerting a major adverse impact on human health by increasing the prevalences of disorders, such as diabetes, hypertension and heart disease. To maintain systemic energy homeostasis, metabolic information must be communicated among organs/tissues. Obesity-related disorders can be thought of as resulting from dysregulation of this vital inter-tissue communication. Remarkable advances in obesity research during this decade have shown humoral factors manufactured and secreted by adipose tissue (adipocytokines) to be of great importance. In addition to these humoral factors, such as nutrients (glucose, fatty acids and amino acids) and hormones (insulin, adipocytokines and so on), the functional significance of the autonomic nervous system has recently attracted research attention. Autonomic nerves are essential components of the endogenous system for maintaining energy homeostasis, making them potential therapeutic targets for obesity-related disorders. This review focuses on the therapeutic possibilities of targeting inter-organ communication systems.

  17. Effect of fatty acids on human bone marrow mesenchymal stem cell energy metabolism and survival.

    Science.gov (United States)

    Fillmore, Natasha; Huqi, Alda; Jaswal, Jagdip S; Mori, Jun; Paulin, Roxane; Haromy, Alois; Onay-Besikci, Arzu; Ionescu, Lavinia; Thébaud, Bernard; Michelakis, Evangelos; Lopaschuk, Gary D

    2015-01-01

    Successful stem cell therapy requires the optimal proliferation, engraftment, and differentiation of stem cells into the desired cell lineage of tissues. However, stem cell therapy clinical trials to date have had limited success, suggesting that a better understanding of stem cell biology is needed. This includes a better understanding of stem cell energy metabolism because of the importance of energy metabolism in stem cell proliferation and differentiation. We report here the first direct evidence that human bone marrow mesenchymal stem cell (BMMSC) energy metabolism is highly glycolytic with low rates of mitochondrial oxidative metabolism. The contribution of glycolysis to ATP production is greater than 97% in undifferentiated BMMSCs, while glucose and fatty acid oxidation combined only contribute 3% of ATP production. We also assessed the effect of physiological levels of fatty acids on human BMMSC survival and energy metabolism. We found that the saturated fatty acid palmitate induces BMMSC apoptosis and decreases proliferation, an effect prevented by the unsaturated fatty acid oleate. Interestingly, chronic exposure of human BMMSCs to physiological levels of palmitate (for 24 hr) reduces palmitate oxidation rates. This decrease in palmitate oxidation is prevented by chronic exposure of the BMMSCs to oleate. These results suggest that reducing saturated fatty acid oxidation can decrease human BMMSC proliferation and cause cell death. These results also suggest that saturated fatty acids may be involved in the long-term impairment of BMMSC survival in vivo.

  18. Prospects of Anaerobic Digestion Technology in China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    As the world's largest developing country, China must face the problem of managing municipal solid waste, and the challenge of organic waste disposal is even more serious. Considering the characteristics of traditional waste disposal technologies and the subsequent secondary pollution, anaerobic digestion has various advantages such as reduction in the land needed for disposal and preservation of environmental quality. In light of the energy crisis, this paper focuses on the potential production of biogas from biowaste through anaerobic digestion processes, the problems incurred by the waste collection system, and the efficiency of the anaerobic digestion process. Use of biogas in a combined heat and power cogeneration system is also discussed. Finally, the advantages of anaerobic digestion technology for the Chinese market are summarized. The anaerobic digestion is suggested to be a promising treating technology for the organic wastes in China.

  19. Anaerobic biorefinery: Current status, challenges, and opportunities.

    Science.gov (United States)

    Sawatdeenarunat, Chayanon; Nguyen, Duc; Surendra, K C; Shrestha, Shilva; Rajendran, Karthik; Oechsner, Hans; Xie, Li; Khanal, Samir Kumar

    2016-09-01

    Anaerobic digestion (AD) has been in use for many decades. To date, it has been primarily aimed at treating organic wastes, mainly manures and wastewater sludge, and industrial wastewaters. However, with the current advancements, a more open mind is required to look beyond these somewhat restricted original applications of AD. Biorefineries are such concepts, where multiple products including chemicals, fuels, polymers etc. are produced from organic feedstocks. The anaerobic biorefinery concept is now gaining increased attention, utilizing AD as the final disposal step. This review aims at evaluating the potential significance of anaerobic biorefineries, including types of feedstocks, uses for the produced energy, as well as sustainable applications of the generated residual digestate. A comprehensive analysis of various types of anaerobic biorefineries has been developed, including both large-scale and household level applications. Finally, future directives are highlighted showing how anaerobic biorefinery concept could impact the bioeconomy in the near future. PMID:27005786

  20. Effect of ultrasonication on anaerobic degradability of solid waste digestate.

    Science.gov (United States)

    Boni, M R; D'Amato, E; Polettini, A; Pomi, R; Rossi, A

    2016-02-01

    This paper evaluates the effect of ultrasonication on anaerobic biodegradability of lignocellulosic residues. While ultrasonication has been commonly applied as a pre-treatment of the feed substrate, in the present study a non-conventional process configuration based on recirculation of sonicated digestate to the biological reactor was evaluated at the lab-scale. Sonication tests were carried out at different applied energies ranging between 500 and 50,000kJ/kg TS. Batch anaerobic digestion tests were performed on samples prepared by mixing sonicated and untreated substrate at two different ratios (25:75 and 75:25 w/w). The results showed that when applied as a post-treatment of digestate, ultrasonication can positively affect the yield of anaerobic digestion, mainly due to the dissolution effect of complex organic molecules that have not been hydrolyzed by biological degradation. A good correlation was found between the CH4 production yield and the amount of soluble organic matter at the start of digestion tests. The maximum gain in biogas production was 30% compared to that attained with the unsonicated substrate, which was tentatively related to the type and concentration of the metabolic products.

  1. Influence of NO-containing gas flow on various parameters of energy metabolism in erythrocytes.

    Science.gov (United States)

    Martusevich, A K; Solov'yova, A G; Peretyagin, S P; Karelin, V I; Selemir, V D

    2014-11-01

    We studied the influence of NO-containing gas phase on some parameters of energy metabolism in human erythrocytes. Whole blood samples were aerated with gas flows from the Plazon instrument (NO concentrations 800 and 80 ppm) and from the experimental generator (75 ppm). Activity of lactate dehydrogenase in direct and reverse reactions, lactate level, and a number of derived coefficients were estimated. Treatment of blood with 800 ppm NO inhibited erythrocyte energy metabolism, and its 10-fold dilution attenuated the effect. The use of ROS-free gas flow containing 75 ppm of NO promoted optimization of the process under investigation. PMID:25403392

  2. Lymphocytes Mitochondrial Physiology as Biomarker of Energy Metabolism during Fasted and Fed Conditions

    Directory of Open Access Journals (Sweden)

    Erika Cortez

    2012-01-01

    Full Text Available Mitochondria are central coordinators of energy metabolism, and changes of their physiology have long been associated with metabolic disorders. Thus, observations of energy dynamics in different cell types are of utmost importance. Therefore, tools with quick and easy handling are needed for consistent evaluations of such interventions. In this paper, our main hypothesis is that during different nutritional situations lymphocytes mitochondrial physiology could be associated with the metabolism of other cell types, such as cardiomyocytes, and consequently be used as metabolic biomarker. Blood lymphocytes and heart muscle fibers were obtained from both fed and 24 h-fasted mice, and mitochondrial analysis was assessed by high-resolution respirometry and western blotting. Carbohydrate-linked oxidation and fatty acid oxidation were significantly higher after fasting. Carnitine palmitoil transferase 1 and uncouple protein 2 contents were increased in the fasted group, while the glucose transporters 1 and 4 and the ratio phosphorylated AMP-activated protein kinase/AMPK did not change between groups. In summary, under a nutritional status modification, mitochondria demonstrated earlier adaptive capacity than other metabolic sensors such as glucose transporters and AMPK, suggesting the accuracy of mitochondria physiology of lymphocytes as biomarker for metabolic changes.

  3. Rethinking energy in parkinsonian motor symptoms: a potential role for neural metabolic deficits.

    Science.gov (United States)

    Amano, Shinichi; Kegelmeyer, Deborah; Hong, S Lee

    2014-01-01

    Parkinson's disease (PD) is characterized as a chronic and progressive neurodegenerative disorder that results in a variety of debilitating symptoms, including bradykinesia, resting tremor, rigidity, and postural instability. Research spanning several decades has emphasized basal ganglia dysfunction, predominantly resulting from dopaminergic (DA) cell loss, as the primarily cause of the aforementioned parkinsonian features. But, why those particular features manifest themselves remains an enigma. The goal of this paper is to develop a theoretical framework that parkinsonian motor features are behavioral consequence of a long-term adaptation to their inability (inflexibility or lack of capacity) to meet energetic demands, due to neural metabolic deficits arising from mitochondrial dysfunction associated with PD. Here, we discuss neurophysiological changes that are generally associated with PD, such as selective degeneration of DA neurons in the substantia nigra pars compacta (SNc), in conjunction with metabolic and mitochondrial dysfunction. We then characterize the cardinal motor symptoms of PD, bradykinesia, resting tremor, rigidity and gait disturbance, reviewing literature to demonstrate how these motor patterns are actually energy efficient from a metabolic perspective. We will also develop three testable hypotheses: (1) neural metabolic deficits precede the increased rate of neurodegeneration and onset of behavioral symptoms in PD; (2) motor behavior of persons with PD are more sensitive to changes in metabolic/bioenergetic state; and (3) improvement of metabolic function could lead to better motor performance in persons with PD. These hypotheses are designed to introduce a novel viewpoint that can elucidate the connections between metabolic, neural and motor function in PD. PMID:25610377

  4. Energy crisis precedes global metabolic failure in a novel Caenorhabditis elegans Alzheimer Disease model

    Science.gov (United States)

    Fong, Sheng; Teo, Emelyne; Ng, Li Fang; Chen, Ce-Belle; Lakshmanan, Lakshmi Narayanan; Tsoi, Sau Yee; Moore, Philip Keith; Inoue, Takao; Halliwell, Barry; Gruber, Jan

    2016-01-01

    Alzheimer Disease (AD) is a progressive neurological disorder characterized by the deposition of amyloid beta (Aβ), predominantly the Aβ1–42 form, in the brain. Mitochondrial dysfunction and impaired energy metabolism are important components of AD pathogenesis. However, the causal and temporal relationships between them and AD pathology remain unclear. Using a novel C. elegans AD strain with constitutive neuronal Aβ1–42 expression that displays neuromuscular defects and age-dependent behavioural dysfunction reminiscent of AD, we have shown that mitochondrial bioenergetic deficit is an early event in AD pathogenesis, preceding dysfunction of mitochondrial electron transfer chain (ETC) complexes and the onset of global metabolic failure. These results are consistent with an emerging view that AD may be a metabolic neurodegenerative disease, and also confirm that Aβ-driven metabolic and mitochondrial effects can be reproduced in organisms separated by large evolutionary distances. PMID:27653553

  5. CO2 incorporation and 4-hydroxy-2-methylbenzoic acid formation during anaerobic metabolism of m-cresol by a methanogenic consortium

    International Nuclear Information System (INIS)

    The metabolism of m-cresol by methanogenic cultures enriched from domestic sewage sludge was investigated. In the initial studies, bromoethanesulfonic acid was used to inhibit methane production. This led to the accumulation of 4.0 ± 0.8 mol of acetate per mol of m-cresol metabolized. These results suggested that CO2 incorporation occurred because each molecule of m-cresol contained seven carbon atoms, whereas four molecules of acetate product contained a total of eight carbon atoms. To verify this, [14C]bicarbonate was added to bromoethanesulfonic acid-inhibited cultures, and those cultures yielded [14C]acetate. Of the label recovered as acetate, 89% was found in the carboxyl position. Similar cultures fed [methyl-14C]m-cresol yielded methyl-labeled acetate. A 14C-labeled transient intermediate was detected in cultures given either m-cresol and [14C]bicarbonate or bicarbonate and [methyl-14C]m-cresol. The intermediate was identified as 4-hydroxy-2-methylbenzoic acid. In addition, another metabolite was detected and identified as 2-methylbenzoic acid. This compound appeared to be produced only sporadically, and it accumulated in the medium, suggested that the dehydroxylation of 4-hydroxy-2-methylbenzoic acid led to an apparent dead-end product

  6. Short photoperiod increases energy intake, metabolic thermogenesis and organ mass in silky starlings Sturnus sericeus.

    Science.gov (United States)

    Wang, Jia-Qi; Wang, Jia-Jia; Wu, Xu-Jian; Zheng, Wei-Hong; Liu, Jin-Song

    2016-03-18

    Environmental cues play important roles in the regulation of an animal's physiology and behavior. One such cue, photoperiod, plays an important role in the seasonal acclimatization of birds. It has been demonstrated that an animal's body mass, basal metabolic rate (BMR), and energy intake, are all affected by photoperiod. The present study was designed to examine photoperiod induced changes in the body mass, metabolism and metabolic organs of the silky starling, Sturnus sericeus. Captive silky starlings increased their body mass and BMR during four weeks of acclimation to a short photoperiod. Birds acclimated to a short photoperiod also increased the mass of certain organs (liver, gizzard and small intestine), and both gross energy intake (GEI) and digestible energy intake (DEI), relative to those acclimated to a long photoperiod. Furthermore, BMR was positively correlated with body mass, liver mass, GEI and DEI. These results suggest that silky starlings increase metabolic thermogenesis when exposed to a short photoperiod by increasing their body and metabolic organ mass, and their GEI and DEI. These findings support the hypothesis that bird species from temperate climates typically display high phenotypic flexibility in thermogenic capacity. PMID:27029864

  7. Effects of ingesting JavaFit Energy Extreme functional coffee on aerobic and anaerobic fitness markers in recreationally-active coffee consumers

    OpenAIRE

    Kreider Richard B; Wilborn Colin D; Wismann Jennifer A; Taylor Lemuel W; Roberts Michael D; Willoughby Darryn S

    2007-01-01

    Abstract The purpose of this study was to examine the effects of ingesting JavaFit™ Energy Extreme (JEE) on aerobic and anaerobic performance measures in recreationally-active male and female coffee drinkers. Five male (27.6 ± 4.2 yrs, 93.2 ± 11.7 kg, 181.6 ± 6.9 cm) and five female (29 ± 4.6 yrs, 61.5 ± 9.2 kg, 167.6 ± 6.9 cm) regular coffee drinkers (i.e., 223.9 ± 62.7 mg·d-1 of caffeine) participated in this study. In a cross-over, randomized design, participants performed a baseline (BASE...

  8. Preservation of rat skeletal muscle energy metabolism by illumination.

    Science.gov (United States)

    Lindgård, Ann; Lundberg, Jonas; Rakotonirainy, Olivier; Elander, Anna; Soussi, Bassam

    2003-04-25

    Skeletal muscle viability is crucially dependent on the tissue levels of its high energy phosphates. In this study we investigated the effect of the preservation medium Perfadex and illumination with Singlet Oxygen Energy (SOE). Singlet oxygen can be produced photochemically by energy transfer from an excited photosensitizer. The energy emitted from singlet oxygen upon relaxation to its triplet state is captured as photons at 634 nm and is here referred to as SOE. Rat hind limb rectus femoris muscles were preserved for five hours at 22 degrees C in Perfadex, saline, SOE illuminated Perfadex or SOE illuminated saline. Extracts of the muscles were analysed by 31P NMR. Data were analysed using two-way analysis of variance and are given as mean values micromol/g dry weight) +/- SEM. The ATP concentration was higher (p = 0.006) in saline groups (4.52) compared with Perfadex groups (2.82). There was no statistically significant difference in PCr between the saline groups (1.25) and Perfadex groups (0.82). However, there were higher (p = 0.003) ATP in the SOE illuminated groups (4.61) compared with the non-illuminated groups (2.73). The PCr was also higher (p < 0.0001) in the SOE illuminated groups (1.89) compared with the non-illuminated groups (0.18). In conclusion, Perfadex in this experimental model was incapable of preserving the high energy phosphates in skeletal muscle during 5 hours of ischemia. Illumination with SOE at 634 nm improved the preservation potential, in terms of a positive effect on the energy status of the muscle cell.

  9. Energy analysis for a sustainable future multi-scale integrated analysis of societal and ecosystem metabolism

    CERN Document Server

    Giampietro, Mario; Sorman, Alevgül H

    2013-01-01

    The vast majority of the countries of the world are now facing an imminent energy crisis, particularly the USA, China, India, Japan and EU countries, but also developing countries having to boost their economic growth precisely when more powerful economies will prevent them from using the limited supply of fossil energy. Despite this crisis, current protocols of energy accounting have been developed for dealing with fossil energy exclusively and are therefore not useful for the analysis of alternative energy sources. The first part of the book illustrates the weakness of existing analyses of energy problems: the science of energy was born and developed neglecting the issue of scale. The authors argue that it is necessary to adopt more complex protocols of accounting and analysis in order to generate robust energy scenarios and effective assessments of the quality of alternative energy sources. The second part of the book introduces the concept of energetic metabolism of modern societies and uses empirical res...

  10. On the use of prior information in modelling metabolic utilization of energy in growing pigs

    DEFF Research Database (Denmark)

    Strathe, Anders Bjerring; Jørgensen, Henry; Fernández, José Adalberto;

    2011-01-01

    Construction of models that provide a realistic representation of metabolic utilization of energy in growing animals tend to be over-parameterized because data generated from individual metabolic studies are often sparse. In the Bayesian framework prior information can enter the data analysis...... through formal statements of probability because model parameters are random variables and hence, are assigned probability distribution (Gelman et al. 2004). The objective of the study was to introduce prior information in modelling metabolizable energy (ME) intake, protein (PD) and lipid deposition (LD......) curves, resulting from a metabolism study on growing pigs of high genetic potential. A total of 17 crossbred pigs of three genders (barrows, boars and gilts) were used. Pigs were fed four diets based on barley, wheat and soybean meal supplemented with crystalline amino acids to meet Danish nutrient...

  11. High fat diet induced disturbances of energy metabolism

    NARCIS (Netherlands)

    Berg, Sjoerd Adrianus Antonius van den

    2010-01-01

    Obesity and insulin resistance (IR) are multifactorial pathologies, characterized by a complex etiology. In addition to genetics, age and sex, environmental factors such as dietary composition and lifestyle have profound effects on the development of both pathologies. Excess dietary energy intake (E

  12. Metabolism of hyperthermophiles.

    Science.gov (United States)

    Schönheit, P; Schäfer, T

    1995-01-01

    Hyperthermophiles are characterized by a temperature optimum for growth between 80 and 110°C. They are considered to represent the most ancient phenotype of living organisms and thus their metabolic design might reflect the situation at an early stage of evolution. Their modes of metabolism are diverse and include chemolithoautotrophic and chemoorganoheterotrophic. No extant phototrophic hyperthermophiles are known. Lithotrophic energy metabolism is mostly anaerobic or microaerophilic and based on the oxidation of H2 or S coupled to the reduction of S, SO inf4 (sup2-) , CO2 and NO inf3 (sup-) but rarely to O2. the substrates are derived from volcanic activities in hyperthermophilic habitats. The lithotrophic energy metabolism of hyperthermophiles appears to be similar to that of mesophiles. Autotrophic CO2 fixation proceeds via the reductive citric acid cycle, considered to be one of the first metabolic cycles, and via the reductive acetyl-CoA/carbon monoxide dehydrogenase pathway. The Calvin cycle has not been found in hyperthermophiles (or any Archaea). Organotrophic metabolism mainly involves peptides and sugars as substrates, which are either oxidized to CO2 by external electron acceptors or fermented to acetate and other products. Sugar catabolism in hyperthermophiles involves non-phosphorylated versions of the Entner-Doudoroff pathway and modified versions of the Embden-Meyerhof pathway. The 'classical' Embden-Meyerhof pathway is present in hyperthermophilic Bacteria (Thermotoga) but not in Archaea. All hyperthermophiles (and Archaea) tested so far utilize pyruvate:ferredoxin oxidoreductase for acetyl-CoA formation from pyruvate. Acetyl-CoA oxidation in anaerobic sulphur-reducing and aerobic hyperthermophiles proceeds via the citric acid cycle; in the hyperthermophilic sulphate-reducer Archaeoglobus an oxidative acetyl-CoA/carbon monoxide dehydrogenase pathway is operative. Acetate formation from acetyl-CoA in Archaea, including hyperthermophiles, is

  13. Microbial network for waste activated sludge cascade utilization in an integrated system of microbial electrolysis and anaerobic fermentation

    DEFF Research Database (Denmark)

    Liu, Wenzong; He, Zhangwei; Yang, Chunxue;

    2016-01-01

    Background: Bioelectrochemical systems have been considered a promising novel technology that shows an enhanced energy recovery, as well as generation of value-added products. A number of recent studies suggested that an enhancement of carbon conversion and biogas production can be achieved...... in an integrated system of microbial electrolysis cell (MEC) and anaerobic digestion (AD) for waste activated sludge (WAS). Microbial communities in integrated system would build a thorough energetic and metabolic interaction network regarding fermentation communities and electrode respiring communities...

  14. Environmental physiology: effects of energy-related pollutants on daily cycles of energy metabolism, motor activity, and thermoregulation

    International Nuclear Information System (INIS)

    This section contains a summary of research on the effects of energy-related pollutants on daily cycles of energy metabolism, motor activity, and thermoregulation. So far, mice have been exposed to fast neutron-gamma radiation or to the chemical effluents of an atmospheric pressure experimental fluidized-bed combustor. The physiological parameters measured included: O2 consumption; CO2 production; motor activity; and deep body temperatures

  15. Feasibility of anaerobic membrane bioreactors (AnMBR) for onsite sanitation and resource recovery (nutrients, energy and water) in urban slums.

    Science.gov (United States)

    Bair, Robert A; Ozcan, Onur Y; Ozcan, Onur O; Calabria, Jorge L; Dick, George H; Yeh, Daniel H

    2015-01-01

    Slums are challenging locations for sanitation technologies. High population densities, a lack of water and electricity infrastructure, and space constraints combine to ensure that many traditional waste treatment technologies fail when implemented in this context. This paper proposes the use of anaerobic membrane bioreactors (AnMBRs) for slum sanitation. AnMBRs allow for localized water reuse, high quality treatment, and energy production at the point of treatment. A water, energy, nutrient, and mass balance was conducted on a theoretical AnMBR directly coupled to a public toilet. The combined system would be capable of recycling its water for use in toilet flushing and would be capable of providing enough energy to power both the toilet and AnMBR operation. The addition of food waste to the feed would help to ensure process stability and energy production by the AnMBR. Ammonia accumulation within the system would have to be managed through struvite precipitation, ion exchange, oxidation, plant uptake or other means. Generated biogas can be converted into heat and/or electricity using small scale gas generators. AnMBR technology has high potential for success in slum settings, if considerations for maintenance and supplies are made as part of the design and system delivery.

  16. Feasibility of anaerobic membrane bioreactors (AnMBR) for onsite sanitation and resource recovery (nutrients, energy and water) in urban slums.

    Science.gov (United States)

    Bair, Robert A; Ozcan, Onur Y; Ozcan, Onur O; Calabria, Jorge L; Dick, George H; Yeh, Daniel H

    2015-01-01

    Slums are challenging locations for sanitation technologies. High population densities, a lack of water and electricity infrastructure, and space constraints combine to ensure that many traditional waste treatment technologies fail when implemented in this context. This paper proposes the use of anaerobic membrane bioreactors (AnMBRs) for slum sanitation. AnMBRs allow for localized water reuse, high quality treatment, and energy production at the point of treatment. A water, energy, nutrient, and mass balance was conducted on a theoretical AnMBR directly coupled to a public toilet. The combined system would be capable of recycling its water for use in toilet flushing and would be capable of providing enough energy to power both the toilet and AnMBR operation. The addition of food waste to the feed would help to ensure process stability and energy production by the AnMBR. Ammonia accumulation within the system would have to be managed through struvite precipitation, ion exchange, oxidation, plant uptake or other means. Generated biogas can be converted into heat and/or electricity using small scale gas generators. AnMBR technology has high potential for success in slum settings, if considerations for maintenance and supplies are made as part of the design and system delivery. PMID:26524445

  17. CHANGES IN THE PHYSIOLOGICAL PERFORMANCE AND ENERGY METABOLISM OF AN ESTUARINE MYSID

    Science.gov (United States)

    Measures of physiological performance and energy metabolism were made on an estuarine mysid (Mysidopsis bahia) exposed throughout a life cycle to the defoliant DEF. EF concentrations > 0.246 ug/l reduced survival through release of the first brood. oung production was completely ...

  18. Malolactic Fermentation : Electrogenic Malate Uptake and Malate/Lactate Antiport Generate Metabolic Energy

    NARCIS (Netherlands)

    Poolman, Bert; Molenaar, Douwe; Smid, Eddy J.; Ubbink, Trees; Abee, Tjakko; Renault, Pierre P.; Konings, Wil N.

    1991-01-01

    The mechanism of metabolic energy production by malolactic fermentation in Lactococcus lactis has been investigated. In the presence of L-malate, a proton motive force composed of a membrane potential and pH gradient is generated which has about the same magnitude as the proton motive force generate

  19. Variation in energy intake and basal metabolic rate of a bird migrating in a wind tunnel

    NARCIS (Netherlands)

    Lindström, Å.; Klaassen, M.R.J.; Kvist, A.

    1999-01-01

    1. We studied the changes in body mass, metabolizable energy intake rate (ME) and basal metabolic rate (BMR) of a Thrush Nightingale, Luscinia luscinia, following repeated 12-h migratory flights in a wind tunnel. In total the bird flew for 176 h corresponding to 6300 km. This is the first study wher

  20. PGC-1 coactivators: inducible regulators of energy metabolism in health and disease

    OpenAIRE

    Finck, Brian N; Kelly, Daniel P.

    2006-01-01

    Members of the PPARγ coactivator-1 (PGC-1) family of transcriptional coactivators serve as inducible coregulators of nuclear receptors in the control of cellular energy metabolic pathways. This Review focuses on the biologic and physiologic functions of the PGC-1 coactivators, with particular emphasis on striated muscle, liver, and other organ systems relevant to common diseases such as diabetes and heart failure.

  1. Energy metabolism and lactation performance of primiparous sows as affected by dietary fat and vitamin E.

    NARCIS (Netherlands)

    Babinszky, L.

    1992-01-01

    In this thesis different levels of dietary fat (37, 43, 75 and 125 g/kg DM, respectively) and vitamin E (from 14 to 151 mg α-tocopherol/kg diet) in the lactation diet, were studied for their effect on the energy metabolism, and lactation performance of primiparous sows. The effects of different leve

  2. The energy metabolism of Fasciola hepatica during its development in the final host

    NARCIS (Netherlands)

    Tielens, A.G.M.; Heuvel, J.M. van den; Bergh, S.G. van den

    1984-01-01

    Mature liver flukes, Fasciola hepatica, of different ages were isolated from the bile ducts of experimentally infected rats. Their energy metabolism was studied during aerobic incubation with [6-14C]glucose. The results showed that the aerobic potentials of the parenchymal liver flukes are not lost

  3. Changes in energy metabolism of the juvenile Fasciola hepatica during its development in the liver parenchyma

    NARCIS (Netherlands)

    Tielens, A.G.M.; Heuvel, J.M. van den; Bergh, S.G. van den

    1982-01-01

    Juvenile Fasciola hepatica at different stages of development were isolated from the liver parenchyma of experimentally infected rats. Their energy metabolism was studied by incubation with D-[16-14C]glucose and compared with that of juveniles isolated immediately after in vitro emergence from the m

  4. Hepatic ERK activity plays a role in energy metabolism.

    Science.gov (United States)

    Jiao, Ping; Feng, Bin; Li, Yujie; He, Qin; Xu, Haiyan

    2013-08-15

    Mitogen activated protein kinases (MAPKs), such as c-Jun N-terminal kinase (JNK) and P38, have been reported to play important roles in energy homeostasis. In this study, we show that the activity of extracellular signal-regulated kinase (ERK) is increased in the livers of diet induced and genetically obese mice. Activation of ERK in the livers of lean mice by over-expressing the constitutively active MAPK kinase 1 (MEK CA) results in decreased energy expenditure, lowered expression of genes involved in fatty acid oxidation, increases fasting hyperglycemia and causes systemic insulin resistance. Interestingly, hepatic glycogen content is markedly increased and expression of G6Pase gene is decreased in mice over-expressing MEK CA compared to control mice expressing green fluorescent protein (GFP), therefore hepatic glucose output is not likely the major contributor of hyperglycemia. One potential mechanism of decreased expression of G6Pase gene by MEK CA is likely due to ERK mediated phosphorylation and cytosolic retention of FOXO1. Adipocytes isolated from MEK CA mice display increased lipolysis. Circulating levels of free fatty acids (FFAs) in these mice are also increased, which possibly contribute to systemic insulin resistance and subsequent hyperglycemia. Consistent with these results, knocking down ERK expression in the liver of diet induced obese (DIO) mice improves systemic insulin and glucose tolerance. These results indicate that increased hepatic ERK activity in DIO mice may contribute to increased liver glycogen content and decreased energy expenditure in obesity. PMID:23732116

  5. Adipose tissue lipolysis and energy metabolism in early cancer cachexia in mice.

    Science.gov (United States)

    Kliewer, Kara L; Ke, Jia-Yu; Tian, Min; Cole, Rachel M; Andridge, Rebecca R; Belury, Martha A

    2015-01-01

    Cancer cachexia is a progressive metabolic disorder that results in depletion of adipose tissue and skeletal muscle. A growing body of literature suggests that maintaining adipose tissue mass in cachexia may improve quality-of-life and survival outcomes. Studies of lipid metabolism in cachexia, however, have generally focused on later stages of the disorder when severe loss of adipose tissue has already occurred. Here, we investigated lipid metabolism in adipose, liver and muscle tissues during early stage cachexia - before severe fat loss - in the colon-26 murine model of cachexia. White adipose tissue mass in cachectic mice was moderately reduced (34-42%) and weight loss was less than 10% of initial body weight in this study of early cachexia. In white adipose depots of cachectic mice, we found evidence of enhanced protein kinase A - activated lipolysis which coincided with elevated total energy expenditure and increased expression of markers of brown (but not white) adipose tissue thermogenesis and the acute phase response. Total lipids in liver and muscle were unchanged in early cachexia while markers of fatty oxidation were increased. Many of these initial metabolic responses contrast with reports of lipid metabolism in later stages of cachexia. Our observations suggest intervention studies to preserve fat mass in cachexia should be tailored to the stage of cachexia. Our observations also highlight a need for studies that delineate the contribution of cachexia stage and animal model to altered lipid metabolism in cancer cachexia and identify those that most closely mimic the human condition.

  6. Structure and function of enzymes involved in the anaerobic degradation of L-threonine to propionate

    Indian Academy of Sciences (India)

    Dhirendra K Simanshu; Sagar Chittori; H S Savithri; M R N Murthy

    2007-09-01

    In Escherichia coli and Salmonella typhimurium, L-threonine is cleaved non-oxidatively to propionate via 2-ketobutyrate by biodegradative threonine deaminase, 2-ketobutyrate formate-lyase (or pyruvate formate-lyase), phosphotransacetylase and propionate kinase. In the anaerobic condition, L-threonine is converted to the energy-rich keto acid and this is subsequently catabolised to produce ATP via substrate-level phosphorylation, providing a source of energy to the cells. Most of the enzymes involved in the degradation of L-threonine to propionate are encoded by the anaerobically regulated tdc operon. In the recent past, extensive structural and biochemical studies have been carried out on these enzymes by various groups. Besides detailed structural and functional insights, these studies have also shown the similarities and differences between the other related enzymes present in the metabolic network. In this paper, we review the structural and biochemical studies carried out on these enzymes.

  7. Basal metabolic rate in relation to body composition and daily energy expenditure in the field vole, Microtus agrestis

    NARCIS (Netherlands)

    Meerlo, P; Bolle, L; Visser, GH; Masman, D; Daan, S

    1997-01-01

    Basal metabolic rate in the field vole (Microtus agrestis) was studied in relation to body composition and daily energy expenditure in the field Daily energy expenditure was measured by means of doubly labelled water ((D2O)-O-18). In the same individuals, basal metabolic rate was subsequently derive

  8. Upflow anaerobic sludge blanket reactor--a review.

    Science.gov (United States)

    Bal, A S; Dhagat, N N

    2001-04-01

    Biological treatment of wastewater basically reduces the pollutant concentration through microbial coagulation and removal of non-settleable organic colloidal solids. Organic matter is biologically stabilized so that no further oxygen demand is exerted by it. The biological treatment requires contact of the biomass with the substrate. Various advances and improvements in anaerobic reactors to achieve variations in contact time and method of contact have resulted in development of in suspended growth systems, attached growth or fixed film systems or combinations thereof. Although anaerobic systems for waste treatment have been used since late 19th century, they were considered to have limited treatment efficiencies and were too slow to serve the needs of a quickly expanding wastewater volume, especially in industrialized and densely populated areas. At present aerobic treatment is the most commonly used process to reduce the organic pollution level of both domestic and industrial wastewaters. Aerobic techniques, such as activated sludge process, trickling filters, oxidation ponds and aerated lagoons, with more or less intense mixing devices, have been successfully installed for domestic wastewater as well as industrial wastewater treatment. Anaerobic digestion systems have undergone modifications in the last two decades, mainly as a result of the energy crisis. Major developments have been made with regard to anaerobic metabolism, physiological interactions among different microbial species, effects of toxic compounds and biomass accumulation. Recent developments however, have demonstrated that anaerobic processes might be an economically attractive alternative for the treatment of different types of industrial wastewaters and in (semi-) tropical areas also for domestic wastewaters. The anaerobic degradation of complex, particulate organic matter has been described as a multistep process of series and parallel reactions. It involves the decomposition of organic and

  9. Eyeless Mexican cavefish save energy by eliminating the circadian rhythm in metabolism.

    Directory of Open Access Journals (Sweden)

    Damian Moran

    Full Text Available The eyed surface form and eyeless cave form of the Mexican tetra Astyanax mexicanus experience stark differences in the daily periodicities of light, food and predation, factors which are likely to have a profound influence on metabolism. We measured the metabolic rate of Pachón cave and surface fish at a fixed swimming speed under light/dark and constant dark photoperiods. In constant darkness surface forms exhibited a circadian rhythm in metabolism with an increase in oxygen demand during the subjective daytime, whereas cave forms did not. The lack of circadian rhythm in metabolism leads to a 27% energy savings for Pachón cave fish compared to surface fish when comparing both forms in their natural photoperiods. When surface forms were tested under constant dark conditions they expended 38% more energy than cave forms under equivalent conditions. Elimination of the circadian rhythm in metabolism may be a general feature of animals that live in perpetually dark food-limited environments such as caves or the deep sea.

  10. Energy metabolism in human pluripotent stem cells and their differentiated counterparts.

    Directory of Open Access Journals (Sweden)

    Sandra Varum

    Full Text Available Human pluripotent stem cells have the ability to generate all cell types present in the adult organism, therefore harboring great potential for the in vitro study of differentiation and for the development of cell-based therapies. Nonetheless their use may prove challenging as incomplete differentiation of these cells might lead to tumoregenicity. Interestingly, many cancer types have been reported to display metabolic modifications with features that might be similar to stem cells. Understanding the metabolic properties of human pluripotent stem cells when compared to their differentiated counterparts can thus be of crucial importance. Furthermore recent data has stressed distinct features of different human pluripotent cells lines, namely when comparing embryo-derived human embryonic stem cells (hESCs and induced pluripotent stem cells (IPSCs reprogrammed from somatic cells.We compared the energy metabolism of hESCs, IPSCs, and their somatic counterparts. Focusing on mitochondria, we tracked organelle localization and morphology. Furthermore we performed gene expression analysis of several pathways related to the glucose metabolism, including glycolysis, the pentose phosphate pathway and the tricarboxylic acid (TCA cycle. In addition we determined oxygen consumption rates (OCR using a metabolic extracellular flux analyzer, as well as total intracellular ATP levels by high performance liquid chromatography (HPLC. Finally we explored the expression of key proteins involved in the regulation of glucose metabolism.Our results demonstrate that, although the metabolic signature of IPSCs is not identical to that of hESCs, nonetheless they cluster with hESCs rather than with their somatic counterparts. ATP levels, lactate production and OCR revealed that human pluripotent cells rely mostly on glycolysis to meet their energy demands. Furthermore, our work points to some of the strategies which human pluripotent stem cells may use to maintain high

  11. New Understanding on Metabolism of Anaerobic Ammonium Oxidation Bacteria Based on Metagenomics Technology%基于宏基因组技术获得的对厌氧氨氧化菌代谢的新理解

    Institute of Scientific and Technical Information of China (English)

    丁爽; 郑平; 陆慧锋; 唐崇俭

    2012-01-01

    厌氧氨氧化菌(Anaerobic ammonium oxidation bacteria,AAOB)是化能自养菌,由于其生理代谢的奇异性、细胞结构的特殊性以及对氮素循环的重要性,已成为环境工程、微生物以及海洋生物学等领域的研究热点.然而.AAOB未能实现纯培养的现状已成为AAOB代谢途径研究的巨大障碍近年来兴起的宏基因组技术(Metagenomics)为AAOB代谢途径的研究提供了新手段.采用宏基因组技术,可直接研究微生物群体中某特定微生物基因组的结构与功能,摆脱了传统微生物学研究对纯培养的依赖,使未培养微生物的认识和开发成为可能本文首先简述获取AAOB宏基因组信息的过程,然后通过比较由传统代谢研究方法和宏基因组技术获得的AAOB代谢途径的研究成果,论述基于宏基因组技术获得的对AAOB代谢的新理解,得出以下结果和结论:1)AAOB的碳素固定途径为乙酰辅酶A途径,碳素固定的还原力来自NADH或者QH2;2)AAOB氮素转化的重要中问产物是NO,而非NH2OH,并提出了以NO为核心的AAOB代谢的改进模型;3)AAOB的ATP合成途径为氧化磷酸化,推测的电子传递途径为N2H4-QH2-细胞色素bc1 复合体;细胞色素bc1复合体再将电子用于NO2还原和N2H4合成AAOB的宏基因组技术使AAOB代谢途径的研究更具方向性.随着分子生物学理论和技术的不断发展,宏基因组学的升级技术(如宏转录组学、宏蛋白质组学)将为AAOB代谢途径的研究提供新的方法与平台.%Anaerobic ammonium oxidation bacteria (AAOB) belong to chemolitho-autotrophs. AAOB have become one of the research hotspots in the field of environmental engineering, microbiology and oceanography because of their specificities in metabolism, cell structure and nitrogen cycle. However, AAOB can not been cultivated in pure culture, which has become a great obstacle to study their metabolic pathways in further. Nowadays, fast-developing metagenomics provides

  12. The effects of chronic cadmium exposure on repeat swimming performance and anaerobic metabolism in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis).

    Science.gov (United States)

    Cunningham, Jessie L; McGeer, James C

    2016-04-01

    This study investigates the effect of chronic Cd exposure on the ability to perform repeat swim challenges in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis). Fish were exposed to waterborne Cd (18nM) in moderately hard water (120mgL(-1) CaCO3) for 30 days. This level of exposure has been shown to cause sublethal physiological disruption and acclimation responses but no impairment of sustained swimming capacity (Ucrit) in single swim challenges. Swim trials were done over the course of the exposure and each one consisted of an initial swim to 85% of the Ucrit of control fish, a 30min recovery period and finally a second swim challenge to determine Ucrit. Plasma and tissue samples were collected before and after each of the swim periods. As expected from previous studies, Cd exposure resulted in significant accumulation of Cd in gills, liver and kidney but not in white muscle. Exposure also induced a loss of plasma Ca followed by subsequent recovery (in lake whitefish but not brown trout) with few mortalities (100% survival for lake whitefish and 93% for brown trout). Both control and exposed fish swam to 85% of the single swim Ucrit and no differences in performance were seen. The Ucrit of unexposed controls in the second swim challenges were not different from the single swim Ucrit. However, second swim performance was significantly reduced in Cd exposed fish, particularly after a week of exposure where 31% and 38% reductions were observed for brown trout and lake whitefish respectively. Swimming to 85% Ucrit resulted in metabolic expenditure with little recovery after 30min. Few differences were observed between control and Cd exposed fish with the exception of a reduction in resting white muscle ATP stores of Cd exposed fish after 1 week of exposure. The results show that chronic sublethal Cd exposure results in an impairment of swimming ability in repeat swim challenges but this impairment is generally not related to metabolic processes

  13. The effects of chronic cadmium exposure on repeat swimming performance and anaerobic metabolism in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis).

    Science.gov (United States)

    Cunningham, Jessie L; McGeer, James C

    2016-04-01

    This study investigates the effect of chronic Cd exposure on the ability to perform repeat swim challenges in brown trout (Salmo trutta) and lake whitefish (Coregonus clupeaformis). Fish were exposed to waterborne Cd (18nM) in moderately hard water (120mgL(-1) CaCO3) for 30 days. This level of exposure has been shown to cause sublethal physiological disruption and acclimation responses but no impairment of sustained swimming capacity (Ucrit) in single swim challenges. Swim trials were done over the course of the exposure and each one consisted of an initial swim to 85% of the Ucrit of control fish, a 30min recovery period and finally a second swim challenge to determine Ucrit. Plasma and tissue samples were collected before and after each of the swim periods. As expected from previous studies, Cd exposure resulted in significant accumulation of Cd in gills, liver and kidney but not in white muscle. Exposure also induced a loss of plasma Ca followed by subsequent recovery (in lake whitefish but not brown trout) with few mortalities (100% survival for lake whitefish and 93% for brown trout). Both control and exposed fish swam to 85% of the single swim Ucrit and no differences in performance were seen. The Ucrit of unexposed controls in the second swim challenges were not different from the single swim Ucrit. However, second swim performance was significantly reduced in Cd exposed fish, particularly after a week of exposure where 31% and 38% reductions were observed for brown trout and lake whitefish respectively. Swimming to 85% Ucrit resulted in metabolic expenditure with little recovery after 30min. Few differences were observed between control and Cd exposed fish with the exception of a reduction in resting white muscle ATP stores of Cd exposed fish after 1 week of exposure. The results show that chronic sublethal Cd exposure results in an impairment of swimming ability in repeat swim challenges but this impairment is generally not related to metabolic processes

  14. Multivariate monitoring of anaerobic co-digestion

    DEFF Research Database (Denmark)

    Madsen, Michael; Holm-Nielsen, Jens Bo

    Anaerobic digestion processes for production of renewable energy in the form of biogas, and in the future hydrogen, are becoming increasingly important worldwide. Sustainable solutions for renewable energy production systems are given high political priority, amongst other things due to global...... warming and environmental concerns. Anaerobic digestion applied in agriculture can simultaneously convert heterogeneous biomasses and wastes from the primary agricultural sector and from the bio processing industries, for instance food processing, pharma, and biofuel production, into valuable organic...... distinct scales. The aim was to investigate, whether changes in the chemical environment in the anaerobic digesters could be monitored by NIRS enabling biogas plant operators to respond to the process dynamics. Results show that several key intermediates suitable for control of the anaerobic digestion...

  15. The Pasteur effect in facultative anaerobic metazoa.

    Science.gov (United States)

    Schmidt, H; Kamp, G

    1996-05-15

    The existence and the regulatory mechanisms of the Pasteur effect in facultative anaerobic metazoa are discussed. There are three reasons for the controversy surrounding this phenomenon. 1) The different definitions of the Pasteur effect, 2) the antagonistic effect of metabolic depression and its species specific response to hypoxia, as well as 3) the laboratory-specific differences in the experimental procedures for analyzing the Pasteur effect and its regulation. This review aims to clarify the confusion about the existence of the Pasteur effect in facultative anaerobic metazoa and to offer possible molecular mechanisms.

  16. Sleep fragmentation alters brain energy metabolism without modifying hippocampal electrophysiological response to novelty exposure

    KAUST Repository

    Baud, Maxime O.

    2016-05-03

    © 2016 European Sleep Research Society. Sleep is viewed as a fundamental restorative function of the brain, but its specific role in neural energy budget remains poorly understood. Sleep deprivation dampens brain energy metabolism and impairs cognitive functions. Intriguingly, sleep fragmentation, despite normal total sleep duration, has a similar cognitive impact, and in this paper we ask the question of whether it may also impair brain energy metabolism. To this end, we used a recently developed mouse model of 2 weeks of sleep fragmentation and measured 2-deoxy-glucose uptake and glycogen, glucose and lactate concentration in different brain regions. In order to homogenize mice behaviour during metabolic measurements, we exposed them to a novel environment for 1 h. Using an intra-hippocampal electrode, we first showed that hippocampal electroencephalograph (EEG) response to exploration was unaltered by 1 or 14 days of sleep fragmentation. However, after 14 days, sleep fragmented mice exhibited a lower uptake of 2-deoxy-glucose in cortex and hippocampus and lower cortical lactate levels than control mice. Our results suggest that long-term sleep fragmentation impaired brain metabolism to a similar extent as total sleep deprivation without affecting the neuronal responsiveness of hippocampus to a novel environment.

  17. Water-energy links in cities: the urban metabolism of London

    Science.gov (United States)

    Mijic, A.; Ruiz Cazorla, J.; Keirstead, J.

    2014-12-01

    Rapid urbanisation results in increased water consumption in cities, requiring improved tools for understanding adaptive measures for water resources management under climate change. The energy sector is facing the same challenges and requires equally comprehensive solutions. More frequent water shortages due to climate and land use changes and potential limits on CO2 emissions from fossil fuels that science demands indicate clearly that the next step in the sustainable city development will be to look for the most efficient use of these highly interdependent resources. One of the concepts that could be used for quantifying fundamental flows in an urban environment such as water and energy is the urban metabolism framework. This paper will examine the concept of urban metabolism by quantifying amounts and trends of water and energy consumed in London by four main sectors: residential, industrial, commercial and public. Key data requirements at the sector level will be identified and initial mapping of critical factors for urban sustainability will be provided. Finally, the work will examine the potential of urban metabolism framework to provide data and information for implementing water, energy and greenhouse emissions trade-off 'fit-for-purpose' strategy for water supply security. The paper is a part of the Panta Rhei Research Initiative of the International Association of Hydrological Sciences (IAHS) under the working group of Energy and Food Impacts on Water.

  18. NanR, a Transcriptional Regulator That Binds to the Promoters of Genes Involved in Sialic Acid Metabolism in the Anaerobic Pathogen Clostridium perfringens.

    Directory of Open Access Journals (Sweden)

    Blair Therit

    Full Text Available Among many other virulence factors, Clostridium perfringens produces three sialidases NanH, NanI and NanJ. NanH lacks a secretion signal peptide and is predicted to be an intracellular enzyme, while NanI and NanJ are secreted. Previously, we had identified part of an operon encoding NanE (epimerase and NanA (sialic acid lyase enzymes. Further analysis of the entire operon suggests that it encodes a complete pathway for the transport and metabolism of sialic acid along with a putative transcriptional regulator, NanR. The addition of 30 mM N-acetyl neuraminic acid (Neu5Ac to a semi-defined medium significantly enhanced the growth yield of strain 13, suggesting that Neu5Ac can be used as a nutrient. C. perfringens strain 13 lacks a nanH gene, but has NanI- and NanJ-encoding genes. Analysis of nanI, nanJ, and nanInanJ mutants constructed by homologous recombination revealed that the expression of the major sialidase, NanI, was induced by the addition of Neu5Ac to the medium, and that in separate experiments, the same was true of a nanI-gusA transcriptional fusion. For the nanI and nanJ genes, primer extension identified three and two putative transcription start sites, respectively. Gel mobility shift assays using purified NanR and DNA from the promoter regions of the nanI and nanE genes showed high affinity, specific binding by NanR. We propose that NanR is a global regulator of sialic acid-associated genes and that it responds, in a positive feedback loop, to the concentration of sialic acid in the cell.

  19. Environmental impacts of anaerobic digestion and the use of anaerobic residues as soil amendment

    Energy Technology Data Exchange (ETDEWEB)

    Mosey, F.E. [VFA Services Ltd., Herts (United Kingdom)

    1996-01-01

    This paper defines the environmental role of anaerobic digestion within the overall objective of recovering energy from renewable biomass resources. Examples and opportunities for incorporating anaerobic digestion into biomass-to-energy schemes are discussed, together with environmental aspects of anaerobic digestion plants. These include visual, public amenity, pathogens and public health, odor control, and gaseous emissions. Digestate disposal and the benefits of restrictions on recycling organic wastes and biomass residues back to the land are discussed, particularly as they relate to American and European codes of practice and environmental legislation. The paper concludes that anaerobic digestion, if performed in purpose-designed reactors that efficiently recover and use biogas, is an environmentally benign process that can enhance energy recovery and aid the beneficial land use of plant residues in many biomass-to-energy schemes.

  20. 运动与心脏能量代谢%Exercise and Cardiac Energy Metabolism

    Institute of Scientific and Technical Information of China (English)

    张仁祥; 乔飞跃; 牛洁

    2012-01-01

    心脏的功能取决于高效率能量代谢。不同状态下(病理和生理),心脏能量代谢会发生变化。正常健康的心脏,脂肪酸是主要的底物;疾病的心脏,糖的利用可能更为有益;在运动状态下,乳酸代谢增加。运动诱导心肌肥大能量代谢正常,底物来自于脂肪代谢。特定的核受体转录因子和共激活剂调节与能量代谢底物选择发生变化相关基因的表达。但是涉及到运动益处的确切机制并不清楚,须进一步研究。%Cardiac function depends on efficient energy metabolism. Under different condition (Pathology and physiology), cardiac energy metabolism will change. For healthy heart, fatty acids are the major substrates, while the diseased heart, glucose utilization may be more useful. Under the exercise condition, lactate metabolism in- creases. Exercise induced myocardial hypertrophy of energy metabolism in normal and the substrate from fat me- tabolism. Specific nuclear receptor transcription factor and co - activator adjustment and energy metabolism sub- strate selection change related gene expression. However, the exact mechanism related to exercise benefits is not clear and need further study.

  1. Impact of hypothalamic reactive oxygen species in the control of energy metabolism and food intake

    Directory of Open Access Journals (Sweden)

    Anne eDrougard

    2015-02-01

    Full Text Available Hypothalamus is a key area involved in the control of metabolism and food intake via the integrations of numerous signals (hormones, neurotransmitters, metabolites from various origins. These factors modify hypothalamic neurons activity and generate adequate molecular and behavioral responses to control energy balance. In this complex integrative system, a new concept has been developed in recent years, that includes reactive oxygen species (ROS as a critical player in energy balance. ROS are known to act in many signaling pathways in different peripheral organs, but also in hypothalamus where they regulate food intake and metabolism by acting on different types of neurons, including proopiomelanocortin (POMC and agouti-related protein (AgRP/neuropeptide Y (NPY neurons. Hypothalamic ROS release is under the influence of different factors such as pancreatic and gut hormones, adipokines (leptin, apelin,..., neurotransmitters and nutrients (glucose, lipids,.... The sources of ROS production are multiple including NADPH oxidase, but also the mitochondria which is considered as the main ROS producer in the brain. ROS are considered as signaling molecules, but conversely impairment of this neuronal signaling ROS pathway contributes to alterations of autonomic nervous system and neuroendocrine function, leading to metabolic diseases such as obesity and type 2 diabetes.In this review we focus our attention on factors that are able to modulate hypothalamic ROS release in order to control food intake and energy metabolism, and whose deregulations could participate to the development of pathological conditions. This novel insight reveals an original mechanism in the hypothalamus that controls energy balance and identify hypothalamic ROS signaling as a potential therapeutic strategy to treat metabolic disorders.

  2. Anaerobic catabolism of aromatic compounds: a genetic and genomic view.

    Science.gov (United States)

    Carmona, Manuel; Zamarro, María Teresa; Blázquez, Blas; Durante-Rodríguez, Gonzalo; Juárez, Javier F; Valderrama, J Andrés; Barragán, María J L; García, José Luis; Díaz, Eduardo

    2009-03-01

    Aromatic compounds belong to one of the most widely distributed classes of organic compounds in nature, and a significant number of xenobiotics belong to this family of compounds. Since many habitats containing large amounts of aromatic compounds are often anoxic, the anaerobic catabolism of aromatic compounds by microorganisms becomes crucial in biogeochemical cycles and in the sustainable development of the biosphere. The mineralization of aromatic compounds by facultative or obligate anaerobic bacteria can be coupled to anaerobic respiration with a variety of electron acceptors as well as to fermentation and anoxygenic photosynthesis. Since the redox potential of the electron-accepting system dictates the degradative strategy, there is wide biochemical diversity among anaerobic aromatic degraders. However, the genetic determinants of all these processes and the mechanisms involved in their regulation are much less studied. This review focuses on the recent findings that standard molecular biology approaches together with new high-throughput technologies (e.g., genome sequencing, transcriptomics, proteomics, and metagenomics) have provided regarding the genetics, regulation, ecophysiology, and evolution of anaerobic aromatic degradation pathways. These studies revealed that the anaerobic catabolism of aromatic compounds is more diverse and widespread than previously thought, and the complex metabolic and stress programs associated with the use of aromatic compounds under anaerobic conditions are starting to be unraveled. Anaerobic biotransformation processes based on unprecedented enzymes and pathways with novel metabolic capabilities, as well as the design of novel regulatory circuits and catabolic networks of great biotechnological potential in synthetic biology, are now feasible to approach.

  3. The effect of the creatine analogue beta-guanidinopropionic acid on energy metabolism: a systematic review.

    Directory of Open Access Journals (Sweden)

    Inge Oudman

    Full Text Available BACKGROUND: Creatine kinase plays a key role in cellular energy transport. The enzyme transfers high-energy phosphoryl groups from mitochondria to subcellular sites of ATP hydrolysis, where it buffers ADP concentration by catalyzing the reversible transfer of the high-energy phosphate moiety (P between creatine and ADP. Cellular creatine uptake is competitively inhibited by beta-guanidinopropionic acid. This substance is marked as safe for human use, but the effects are unclear. Therefore, we systematically reviewed the effect of beta-guanidinopropionic acid on energy metabolism and function of tissues with high energy demands. METHODS: We performed a systematic review and searched the electronic databases Pubmed, EMBASE, the Cochrane Library, and LILACS from their inception through March 2011. Furthermore, we searched the internet and explored references from textbooks and reviews. RESULTS: After applying the inclusion criteria, we retrieved 131 publications, mainly considering the effect of chronic oral administration of beta-guanidinopropionic acid (0.5 to 3.5% on skeletal muscle, the cardiovascular system, and brain tissue in animals. Beta-guanidinopropionic acid decreased intracellular creatine and phosphocreatine in all tissues studied. In skeletal muscle, this effect induced a shift from glycolytic to oxidative metabolism, increased cellular glucose uptake and increased fatigue tolerance. In heart tissue this shift to mitochondrial metabolism was less pronounced. Myocardial contractility was modestly reduced, including a decreased ventricular developed pressure, albeit with unchanged cardiac output. In brain tissue adaptations in energy metabolism resulted in enhanced ATP stability and survival during hypoxia. CONCLUSION: Chronic beta-guanidinopropionic acid increases fatigue tolerance of skeletal muscle and survival during ischaemia in animal studies, with modestly reduced myocardial contractility. Because it is marked as safe for human

  4. Cerebral energy metabolism during mitochondrial dysfunction induced by cyanide in piglets

    DEFF Research Database (Denmark)

    Nielsen, Troels Halfeld; Olsen, N.V.; Toft, P;

    2013-01-01

    variables related to energy metabolism. METHODS: Mitochondrial dysfunction was induced in piglets and evaluated by monitoring brain tissue oxygen tension (PbtO2 ) and cerebral levels of glucose, lactate, pyruvate, glutamate, and glycerol bilaterally. The biochemical variables were obtained by microdialysis...... metabolism and degradation of cellular membranes, respectively. CONCLUSION: Mitochondrial dysfunction is characterised by an increased LP ratio signifying a shift in cytoplasmatic redox state at normal or elevated PbtO2 . The condition is biochemically characterised by a marked increase in cerebral lactate...... with a normal or elevated pyruvate level. The metabolic pattern is different from cerebral ischemia, which is characterised by simultaneous decreases in intracerebral pyruvate and PbtO2 . The study supports the hypothesis that cerebral ischemia and mitochondrial dysfunction may be identified and separated...

  5. Genome-scale estimate of the metabolic turnover of E. Coli from the energy balance analysis

    Science.gov (United States)

    De Martino, D.

    2016-02-01

    In this article the notion of metabolic turnover is revisited in the light of recent results of out-of-equilibrium thermodynamics. By means of Monte Carlo methods we perform an exact sampling of the enzymatic fluxes in a genome scale metabolic network of E. Coli in stationary growth conditions from which we infer the metabolites turnover times. However the latter are inferred from net fluxes, and we argue that this approximation is not valid for enzymes working nearby thermodynamic equilibrium. We recalculate turnover times from total fluxes by performing an energy balance analysis of the network and recurring to the fluctuation theorem. We find in many cases values one of order of magnitude lower, implying a faster picture of intermediate metabolism.

  6. Metabolic Disorders

    Science.gov (United States)

    ... as your liver, muscles, and body fat. A metabolic disorder occurs when abnormal chemical reactions in your body ... that produce the energy. You can develop a metabolic disorder when some organs, such as your liver or ...

  7. Gender comparisons in anaerobic power and anaerobic capacity tests.

    OpenAIRE

    Maud, P. J.; Shultz, B B

    1986-01-01

    The purpose of the study was to compare anaerobic power and anaerobic capacity test scores between young active men and women. Three performance measures of anaerobic power and two of anaerobic capacity were administered to a sample comprising 52 male and 50 female college students (means age = 21.4 yrs). Results indicated significant differences between men and women in body height, weight and per cent fat, in fat free mass (FFM), anaerobic power, and anaerobic capacity when recorded as gros...

  8. Rethinking Energy in Parkinsonian Motor Symptoms: A Potential Role for Neural Metabolic Deficits

    Directory of Open Access Journals (Sweden)

    Shinichi eAmano

    2015-01-01

    Full Text Available Parkinson’s disease (PD is characterized as a chronic and progressive neurodegenerative disorder that results in a variety of debilitating symptoms, including bradykinesia, resting tremor, rigidity, and postural instability. Research spanning several decades has emphasized basal ganglia dysfunction, predominantly resulting from dopaminergic cell loss, as the primarily cause of the aforementioned parkinsonian features. But, why those particular features manifest themselves remains an enigma. The goal of this paper is to develop a theoretical framework that parkinsonian motor features are behavioral consequence of a long-term adaptation to their inability (inflexibility or lack of capacity to meet energetic demands, due to neural metabolic deficits arising from mitochondrial dysfunction associated with PD. Here, we discuss neurophysiological changes that are generally associated with PD, such as selective degeneration of dopaminergic neurons in the substantia nigra pars compacta, in conjunction with metabolic and mitochondrial dysfunction. We then characterize the cardinal motor symptoms of PD, bradykinesia, resting tremor, rigidity and gait disturbance, reviewing literature to demonstrate how these motor patterns are actually energy efficient from a metabolic perspective. We will also develop three testable hypotheses: (1 neural metabolic deficits precede the increased rate of neurodegeneration and onset of behavioral symptoms in PD, (2 motor behavior of persons with PD are more sensitive to changes in metabolic/bioenergetic state, and (3 improvement of metabolic function could lead to better motor performance in persons with PD. These hypotheses are designed to introduce a novel viewpoint that can elucidate the connections between metabolic, neural and motor function in PD.

  9. Effects of a low- or a high-carbohydrate diet on performance, energy system contribution, and metabolic responses during supramaximal exercise.

    Science.gov (United States)

    Lima-Silva, Adriano E; Pires, Flavio O; Bertuzzi, Romulo; Silva-Cavalcante, Marcos D; Oliveira, Rodrigo S F; Kiss, Maria Augusta; Bishop, David

    2013-09-01

    The purpose of the present study was to examine the effects of a high- or low-carbohydrate (CHO) diet on performance, aerobic and anaerobic contribution, and metabolic responses during supramaximal exercise. Six physically-active men first performed a cycling exercise bout at 115% maximal oxygen uptake to exhaustion after following their normal diet for 48 h (∼50% of CHO, control test). Seventy-two hours after, participants performed a muscle glycogen depletion exercise protocol, followed by either a high- or low-CHO diet (∼70 and 25% of CHO, respectively) for 48 h, in a random, counterbalanced order. After the assigned diet period (48 h), the supramaximal cycling exercise bout (115% maximal oxygen consumption) to exhaustion was repeated. The low-CHO diet reduced time to exhaustion when compared with both the control and the high-CHO diet (-19 and -32%, respectively, p low-CHO diet was accompanied by a lower total aerobic energy contribution (-39%) compared with the high-CHO diet (p 0.05). The low-CHO diet was associated with a lower blood lactate concentration (p 0.05). In conclusion, a low-CHO diet reduces both performance and total aerobic energy provision during supramaximal exercise. As peak K(+) concentration was similar, but time to exhaustion shorter, the low-CHO diet was associated with an earlier attainment of peak plasma K(+) concentration.

  10. Simulating the physiology of athletes during endurance sports events: modelling human energy conversion and metabolism.

    Science.gov (United States)

    van Beek, Johannes H G M; Supandi, Farahaniza; Gavai, Anand K; de Graaf, Albert A; Binsl, Thomas W; Hettling, Hannes

    2011-11-13

    The human physiological system is stressed to its limits during endurance sports competition events. We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We calculated heat transfer by conduction and blood flow inside the body, and heat transfer from the skin by radiation, convection and sweat evaporation, resulting in temperature changes in 25 body compartments. We simulated a mountain time trial to Alpe d'Huez during the Tour de France. To approach the time realized by Lance Armstrong in 2004, very high oxygen uptake must be sustained by the simulated cyclist. Temperature was predicted to reach 39°C in the brain, and 39.7°C in leg muscle. In addition to the macroscopic simulation, we analysed the buffering of bursts of high adenosine triphosphate hydrolysis by creatine kinase during cyclical muscle activity at the biochemical pathway level. To investigate the low oxygen to carbohydrate ratio for the brain, which takes up lactate during exercise, we calculated the flux distribution in cerebral energy metabolism. Computational modelling of the human body, describing heat exchange and energy metabolism, makes simulation of endurance sports events feasible.

  11. Unique flexibility in energy metabolism allows mycobacteria to combat starvation and hypoxia.

    Directory of Open Access Journals (Sweden)

    Michael Berney

    Full Text Available Mycobacteria are a group of obligate aerobes that require oxygen for growth, but paradoxically have the ability to survive and metabolize under hypoxia. The mechanisms responsible for this metabolic plasticity are unknown. Here, we report on the adaptation of Mycobacterium smegmatis to slow growth rate and hypoxia using carbon-limited continuous culture. When M. smegmatis is switched from a 4.6 h to a 69 h doubling time at a constant oxygen saturation of 50%, the cells respond through the down regulation of respiratory chain components and the F1Fo-ATP synthase, consistent with the cells lower demand for energy at a reduced growth rate. This was paralleled by an up regulation of molecular machinery that allowed more efficient energy generation (i.e. Complex I and the use of alternative electron donors (e.g. hydrogenases and primary dehydrogenases to maintain the flow of reducing equivalents to the electron transport chain during conditions of severe energy limitation. A hydrogenase mutant showed a 40% reduction in growth yield highlighting the importance of this enzyme in adaptation to low energy supply. Slow growing cells at 50% oxygen saturation subjected to hypoxia (0.6% oxygen saturation responded by switching on oxygen scavenging cytochrome bd, proton-translocating cytochrome bc1-aa3 supercomplex, another putative hydrogenase, and by substituting NAD+-dependent enzymes with ferredoxin-dependent enzymes thus highlighting a new pattern of mycobacterial adaptation to hypoxia. The expression of ferredoxins and a hydrogenase provides a potential conduit for disposing of and transferring electrons in the absence of exogenous electron acceptors. The use of ferredoxin-dependent enzymes would allow the cell to maintain a high carbon flux through its central carbon metabolism independent of the NAD+/NADH ratio. These data demonstrate the remarkable metabolic plasticity of the mycobacterial cell and provide a new framework for understanding their

  12. Energy metabolism determines the sensitivity of human hepatocellular carcinoma cells to mitochondrial inhibitors and biguanide drugs.

    Science.gov (United States)

    Hsu, Chia-Chi; Wu, Ling-Chia; Hsia, Cheng-Yuan; Yin, Pen-Hui; Chi, Chin-Wen; Yeh, Tien-Shun; Lee, Hsin-Chen

    2015-09-01

    Human hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide particularly in Asia. Deregulation of cellular energetics was recently included as one of the cancer hallmarks. Compounds that target the mitochondria in cancer cells were proposed to have therapeutic potential. Biguanide drugs which inhibit mitochondrial complex I and repress mTOR signaling are clinically used to treat type 2 diabetes mellitus patients (T2DM) and were recently found to reduce the risk of HCC in T2DM patients. However, whether alteration of energy metabolism is involved in regulating the sensitivity of HCC to biguanide drugs is still unclear. In the present study, we treated four HCC cell lines with mitochondrial inhibitors (rotenone and oligomycin) and biguanide drugs (metformin and phenformin), and found that the HCC cells which had a higher mitochondrial respiration rate were more sensitive to these treatments; whereas the HCC cells which exhibited higher glycolysis were more resistant. When glucose was replaced by galactose in the medium, the altered energy metabolism from glycolysis to mitochondrial respiration in the HCC cells enhanced the cellular sensitivity to mitochondrial inhibitors and biguanides. The energy metabolism change enhanced AMP-activated protein kinase (AMPK) activation, mTOR repression and downregulation of cyclin D1 and Mcl-1 in response to the mitochondrial inhibitors and biguanides. In conclusion, our results suggest that increased mitochondrial oxidative metabolism upregulates the sensitivity of HCC to biguanide drugs. Enhancing the mitochondrial oxidative metabolism in combination with biguanide drugs may be a therapeutic strategy for HCC.

  13. Unique metabolic features of stem cells, cardiomyocytes, and their progenitors.

    Science.gov (United States)

    Gaspar, John Antonydas; Doss, Michael Xavier; Hengstler, Jan Georg; Cadenas, Cristina; Hescheler, Jürgen; Sachinidis, Agapios

    2014-04-11

    Recently, growing attention has been directed toward stem cell metabolism, with the key observation that the plasticity of stem cells also reflects the plasticity of their energy substrate metabolism. There seems to be a clear link between the self-renewal state of stem cells, in which cells proliferate without differentiation, and the activity of specific metabolic pathways. Differentiation is accompanied by a shift from anaerobic glycolysis to mitochondrial respiration. This metabolic switch of differentiating stem cells is required to cover the energy demands of the different organ-specific cell types. Among other metabolic signatures, amino acid and carbohydrate metabolism is most prominent in undifferentiated embryonic stem cells, whereas the fatty acid metabolic signature is unique in cardiomyocytes derived from embryonic stem cells. Identifying the specific metabolic pathways involved in pluripotency and differentiation is critical for further progress in the field of developmental biology and regenerative medicine. The recently generated knowledge on metabolic key processes may help to generate mature stem cell-derived somatic cells for therapeutic applications without the requirement of genetic manipulation. In the present review, the literature about metabolic features of stem cells and their cardiovascular cell derivatives as well as the specific metabolic gene signatures differentiating between stem and differentiated cells are summarized and discussed.

  14. The Gut Microbiota Modulates Energy Metabolism in the Hibernating Brown Bear Ursus arctos

    DEFF Research Database (Denmark)

    Sommer, Felix; Ståhlman, Marcus; Ilkayeva, Olga;

    2016-01-01

    Hibernation is an adaptation that helps many animals to conserve energy during food shortage in winter. Brown bears double their fat depots during summer and use these stored lipids during hibernation. Although bears seasonally become obese, they remain metabolically healthy. We analyzed the micr......Hibernation is an adaptation that helps many animals to conserve energy during food shortage in winter. Brown bears double their fat depots during summer and use these stored lipids during hibernation. Although bears seasonally become obese, they remain metabolically healthy. We analyzed...... the microbiota of free-ranging brown bears during their active phase and hibernation. Compared to the active phase, hibernation microbiota had reduced diversity, reduced levels of Firmicutes and Actinobacteria, and increased levels of Bacteroidetes. Several metabolites involved in lipid metabolism, including...... triglycerides, cholesterol, and bile acids, were also affected by hibernation. Transplantation of the bear microbiota from summer and winter to germ-free mice transferred some of the seasonal metabolic features and demonstrated that the summer microbiota promoted adiposity without impairing glucose tolerance...

  15. Short- and medium-chain fatty acids in energy metabolism: the cellular perspective.

    Science.gov (United States)

    Schönfeld, Peter; Wojtczak, Lech

    2016-06-01

    Short- and medium-chain fatty acids (SCFAs and MCFAs), independently of their cellular signaling functions, are important substrates of the energy metabolism and anabolic processes in mammals. SCFAs are mostly generated by colonic bacteria and are predominantly metabolized by enterocytes and liver, whereas MCFAs arise mostly from dietary triglycerides, among them milk and dairy products. A common feature of SCFAs and MCFAs is their carnitine-independent uptake and intramitochondrial activation to acyl-CoA thioesters. Contrary to long-chain fatty acids, the cellular metabolism of SCFAs and MCFAs depends to a lesser extent on fatty acid-binding proteins. SCFAs and MCFAs modulate tissue metabolism of carbohydrates and lipids, as manifested by a mostly inhibitory effect on glycolysis and stimulation of lipogenesis or gluconeogenesis. SCFAs and MCFAs exert no or only weak protonophoric and lytic activities in mitochondria and do not significantly impair the electron transport in the respiratory chain. SCFAs and MCFAs modulate mitochondrial energy production by two mechanisms: they provide reducing equivalents to the respiratory chain and partly decrease efficacy of oxidative ATP synthesis. PMID:27080715

  16. Effect of fipronil on energy metabolism in the perfused rat liver.

    Science.gov (United States)

    de Medeiros, Hyllana Catarine Dias; Constantin, Jorgete; Ishii-Iwamoto, Emy Luiza; Mingatto, Fábio Erminio

    2015-07-01

    Fipronil is an insecticide used to control pests in animals and plants that can causes hepatotoxicity in animals and humans, and it is hepatically metabolized to fipronil sulfone by cytochrome P-450. The present study aimed to characterize the effects of fipronil (10-50μM) on energy metabolism in isolated perfused rat livers. In fed animals, there was increased glucose and lactate release from glycogen catabolism, indicating the stimulation of glycogenolysis and glycolysis. In the livers of fasted animals, fipronil inhibited glucose and urea production from exogenous l-alanine, whereas ammonia and lactate production were increased. In addition, fipronil at 50μM concentration inhibited the oxygen uptake and increased the cytosolic NADH/NAD⁺ ratio under glycolytic conditions. The metabolic alterations were found both in livers from normal or proadifen-pretreated rats revealing that fipronil and its reactive metabolites contributed for the observed activity. The effects on oxygen uptake indicated that the possible mechanism of toxicity of fipronil involves impairment on mitochondrial respiratory activity, and therefore, interference with energy metabolism. The inhibitory effects on oxygen uptake observed at the highest concentration of 50μM was abolished by pretreatment of the rats with proadifen indicating that the metabolites of fipronil, including fipronil sulfone, acted predominantly as inhibitors of respiratory chain. The hepatoxicity of both the parent compound and its reactive metabolites was corroborated by the increase in the activity of lactate dehydrogenase in the effluent perfusate in livers from normal or proadifen-pretreated rats. PMID:25943759

  17. TRPV1 activation improves exercise endurance and energy metabolism through PGC-1α upregulation in mice

    Institute of Scientific and Technical Information of China (English)

    Zhidan Luo; Tingbing Cao; Daoyan Liu; Bernd Nilius; Yu Huang; Zhencheng Yan; Zhiming Zhu; Liqun Ma; Zhigang Zhao; Hongbo He; Dachun Yang; Xiaoli Feng; Shuangtao Ma; Xiaoping Chen; Tianqi Zhu

    2012-01-01

    Impaired aerobic exercise capacity and skeletal muscle dysfunction are associated with cardiometabolic diseases.Acute administration of capsaicin enhances exercise endurance in rodents,but the long-term effect of dietary capsaicin is unknown.The capsaicin receptor,the transient receptor potential vanilloid 1(TRPV1)cation channel has been detected in skeletal muscle,the role of which remains unclear.Here we report the function of TRPV1 in cultured C2C12 myocytes and the effect of TRPV1 activation by dietary capsaicin on energy metabolism and exercise endurance of skeletal muscles in mice.In vitro,capsaicin increased cytosolic free calcium and peroxisome proliferator-activated receptor-γ coactivator-1α(PGC-1α)expression in C2C12 myotubes through activating TRPV1.In vivo,PGC-1α in skeletal muscle was upregulated by capsaicin-induced TRPV1 activation or genetic overexpression of TRPV1 in mice.TRPV1 activation increased the expression of genes involved in fatty acid oxidation and mitochondrial respiration,promoted mitochondrial biogenesis,increased oxidative fibers,enhanced exercise endurance and prevented high-fat diet-induced metabolic disorders.Importantly,these effects of capsaicin were absent in TRPV1-deficient mice.We conclude that TRPV1 activation by dietary capsaicin improves energy metabolism and exercise endurance by upregulating PGC-1α in skeletal muscles.The present results indicate a novel therapeutic strategy for managing metabolic diseases and improving exercise endurance.

  18. The roles of nuclear receptors CAR and PXR in hepatic energy metabolism.

    Science.gov (United States)

    Konno, Yoshihiro; Negishi, Masahiko; Kodama, Susumu

    2008-01-01

    Nuclear receptors constitutive active/androstane receptor (CAR) and pregnane X receptor (PXR) were originally characterized as transcription factors regulating the hepatic genes that encode drug metabolizing enzymes. Recent works have now revealed that these nuclear receptors also play the critical roles in modulating hepatic energy metabolism. While CAR and PXR directly bind to their response sequences phenobarbital-responsive enhancer module (PBREM) and xenobiotic responsive enhancer module (XREM) in the promoter of target genes to increase drug metabolism, the receptors also cross talk with various hormone responsive transcription factors such as forkhead box O1 (FoxO1), forkhead box A2 (FoxA2), cAMP-response element binding protein, and peroxisome proliferator activated receptor gamma coactivator 1alpha (PGC 1alpha) to decrease energy metabolism through down-regulating gluconeogenesis, fatty acid oxidation and ketogenesis and up-regulating lipogenesis. In addition, CAR modulates thyroid hormone activity by regulating type 1 deiodinase in the regenerating liver. Thus, CAR and PXR are now placed at the crossroad where both xenobiotics and endogenous stimuli co-regulate liver function.

  19. Effect of fipronil on energy metabolism in the perfused rat liver.

    Science.gov (United States)

    de Medeiros, Hyllana Catarine Dias; Constantin, Jorgete; Ishii-Iwamoto, Emy Luiza; Mingatto, Fábio Erminio

    2015-07-01

    Fipronil is an insecticide used to control pests in animals and plants that can causes hepatotoxicity in animals and humans, and it is hepatically metabolized to fipronil sulfone by cytochrome P-450. The present study aimed to characterize the effects of fipronil (10-50μM) on energy metabolism in isolated perfused rat livers. In fed animals, there was increased glucose and lactate release from glycogen catabolism, indicating the stimulation of glycogenolysis and glycolysis. In the livers of fasted animals, fipronil inhibited glucose and urea production from exogenous l-alanine, whereas ammonia and lactate production were increased. In addition, fipronil at 50μM concentration inhibited the oxygen uptake and increased the cytosolic NADH/NAD⁺ ratio under glycolytic conditions. The metabolic alterations were found both in livers from normal or proadifen-pretreated rats revealing that fipronil and its reactive metabolites contributed for the observed activity. The effects on oxygen uptake indicated that the possible mechanism of toxicity of fipronil involves impairment on mitochondrial respiratory activity, and therefore, interference with energy metabolism. The inhibitory effects on oxygen uptake observed at the highest concentration of 50μM was abolished by pretreatment of the rats with proadifen indicating that the metabolites of fipronil, including fipronil sulfone, acted predominantly as inhibitors of respiratory chain. The hepatoxicity of both the parent compound and its reactive metabolites was corroborated by the increase in the activity of lactate dehydrogenase in the effluent perfusate in livers from normal or proadifen-pretreated rats.

  20. Biochemistry and physiology of anaerobic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-18

    We welcome you to The Power of Anaerobes. This conference serves two purposes. One is to celebrate the life of Harry D. Peck, Jr.,who was born May 18, 1927 and would have celebrated his 73rd birthday at this conference. He died November 20, 1998. The second is to gather investigators to exchange views within the realm of anaerobic microbiology, an area in which tremendous progress has been seen during recent years. It is sufficient to mention discoveries of a new form of life (the archaea), hyper or extreme thermophiles, thermophilic alkaliphiles and anaerobic fungi. With these discoveries has come a new realization about physiological and metabolic properties of microorganisms, and this in turn has demonstrated their importance for the development, maintenance and sustenance of life on Earth.

  1. Upflow anaerobic sludge blanket reactor--a review.

    Science.gov (United States)

    Bal, A S; Dhagat, N N

    2001-04-01

    Biological treatment of wastewater basically reduces the pollutant concentration through microbial coagulation and removal of non-settleable organic colloidal solids. Organic matter is biologically stabilized so that no further oxygen demand is exerted by it. The biological treatment requires contact of the biomass with the substrate. Various advances and improvements in anaerobic reactors to achieve variations in contact time and method of contact have resulted in development of in suspended growth systems, attached growth or fixed film systems or combinations thereof. Although anaerobic systems for waste treatment have been used since late 19th century, they were considered to have limited treatment efficiencies and were too slow to serve the needs of a quickly expanding wastewater volume, especially in industrialized and densely populated areas. At present aerobic treatment is the most commonly used process to reduce the organic pollution level of both domestic and industrial wastewaters. Aerobic techniques, such as activated sludge process, trickling filters, oxidation ponds and aerated lagoons, with more or less intense mixing devices, have been successfully installed for domestic wastewater as well as industrial wastewater treatment. Anaerobic digestion systems have undergone modifications in the last two decades, mainly as a result of the energy crisis. Major developments have been made with regard to anaerobic metabolism, physiological interactions among different microbial species, effects of toxic compounds and biomass accumulation. Recent developments however, have demonstrated that anaerobic processes might be an economically attractive alternative for the treatment of different types of industrial wastewaters and in (semi-) tropical areas also for domestic wastewaters. The anaerobic degradation of complex, particulate organic matter has been described as a multistep process of series and parallel reactions. It involves the decomposition of organic and

  2. A metabolic model for members of the genus Tetrasphaera involved in enhanced biological phosphorus removal

    DEFF Research Database (Denmark)

    Kristiansen, Rikke; Nguyen, Hien Thi Thu; Saunders, Aaron Marc;

    2013-01-01

    and substrate fermentation. During the aerobic phase, the stored glycogen is catabolized to provide energy for growth and to replenish the intracellular polyphosphate reserves needed for subsequent anaerobic metabolism. They are also able to denitrify. This physiology is markedly different to that displayed...... Accumulibacter phosphatis’ is unclear, although they may occupy different ecological niches in EBPR communities. The genomes of four Tetrasphaera isolates (T. australiensis, T. japonica, T. elongata and T. jenkinsii) were sequenced and annotated, and the data used to construct metabolic models. These models...... incorporate central aspects of carbon and phosphorus metabolism critical to understanding their behavior under the alternating anaerobic/aerobic conditions encountered in EBPR systems. Key features of these metabolic pathways were investigated in pure cultures, although poor growth limited their analyses to T...

  3. Anaerobic fermentation of beef cattle manure

    Science.gov (United States)

    Hashimoto, A. G.; Chen, Y. R.; Varel, V. H.

    1981-01-01

    The conversion of livestock manure and crop residues into methane and a high protein feed ingredient by thermophilic anaerobic fermentation is summarized. The major biological and operational factors involved in methanogenesis are discussed, and a kinetic model that describes the fermentation process is presented. Substrate biodegradability, fermentation temperature, and influent substrate concentration to have significant effects on CH4 production rate. Assessment of the energy requirements for anaerobic fermentation systems showed that the major energy requirement for a thermophilic system was for maintaining the fermenter temperature. The next major energy consumption was due to the mixing of the influent slurry and fermenter liquor. An approach to optimizing anaerobic fermenter s by selecting design criteria that maximize the net energy production per unit cost is presented.

  4. III. Cellular ultrastructures in situ as key to understanding tumor energy metabolism: biological significance of the Warburg effect [v1; ref status: indexed, http://f1000r.es/a0

    Directory of Open Access Journals (Sweden)

    Halina Witkiewicz

    2013-01-01

    Full Text Available Despite the universality of metabolic pathways, malignant cells were found to have their metabolism reprogrammed to generate energy by glycolysis even under normal oxygen concentrations (the Warburg effect. Therefore, the pathway energetically 18 times less efficient than oxidative phosphorylation was implicated to match increased energy requirements of growing tumors. The paradox was explained by an abnormally high rate of glucose uptake, assuming unlimited availability of substrates for tumor growth in vivo. However, ultrastructural analysis of tumor vasculature morphogenesis showed that the growing tissue regions did not have continuous blood supply and intermittently depended on autophagy for survival. Erythrogenic autophagy, and resulting ATP generation by glycolysis, appeared critical to initiating vasculature formation where it was missing. This study focused on ultrastructural features that reflected metabolic switch from aerobic to anaerobic. Morphological differences between and within different types of cells were evident in tissue sections. In cells undergoing nucleo-cytoplasmic conversion into erythrosomes (erythrogenesis, gradual changes led to replacing mitochondria with peroxisomes, through an intermediate form connected to endoplasmic reticulum. Those findings related to the issue of peroxisome biogenesis and to the phenomenon of hemogenic endothelium. Mitochondria were compacted also during mitosis. In vivo, cells that lost and others that retained capability to use oxygen coexisted side-by-side; both types were important for vasculature morphogenesis and tissue growth. Once passable, the new vasculature segment could deliver external oxygen and nutrients. Nutritional and redox status of microenvironment had similar effect on metabolism of malignant and non-malignant cells demonstrating the necessity to maintain structure-energy equivalence in all living cells. The role of glycolysis in initiating vasculature formation, and in

  5. Energy valorization of agro-industrial wastes and sweet sorghum for the production of gaseous biofuels through anaerobic digestion

    OpenAIRE

    Δαρειώτη, Μαργαρίτα

    2015-01-01

    It is clear that renewable resources have received great interest from the international community during the last decades and play a crucial role in the current CO2-mitigation policy. In this regard, energy from biomass and waste is seen as one of the most dominant future renewable energy sources. Thus, organic waste i.e. animal wastes, wastewaters, energy crops, agricultural and agro-industrial residues are of specific importance since these sources do not compete with food crops in agricul...

  6. Interplay Between Diet, Gut Microbiota, Immune Cells and Energy Metabolism in Obesity Development

    DEFF Research Database (Denmark)

    Danneskiold-Samsøe, Niels Banhos

    -glycemic carbohydrates such as refined grains and sugars. The lack of sufficient therapeutic options for obesity, and the inability of most individuals to reduce energy intake or increase expenditure highlight the importance of understanding its underlying biological mechanisms. Obesity is associated with low......Obesity and associated metabolic disorders such as type 2 diabetes are major causes of morbidity and mortality globally. A major contributor to development of the obesity pandemic has been the increasing intake of energy dense diets, consisting of dietary fats combined with high...... investigation of the interactions between the diet, gut microbiota and development of inflammation is necessary to understand development of obesity. For this, it is important to understand the regulation of the local immune system of fat and other tissues important for regulation of systemic metabolism...

  7. An integrative approach to energy, carbon, and redox metabolism in the cyanobacterium Synechocystis sp. PCC 6803

    Energy Technology Data Exchange (ETDEWEB)

    Overbeek, Ross; Fonstein, Veronika; Osterman, Andrei; Gerdes, Svetlana; Vassieva, Olga; Zagnitko, Olga; Rodionov, Dmitry

    2005-02-15

    covering energy, carbon, and redox metabolism in the Synechocystis sp. PCC 6803 and other cyanobacteria has been performed (Specific Aim 4). The main objectives for this year (adjusted to reflect a new, public domain, setting of the Project research team) were: Aim 1. To develop, test, and deploy a new open source system, the SEED, for integrating community-based annotation, and comparative analysis of all publicly available microbial genomes. Develop a comprehensive genomic database by integrating within SEED all publicly available complete and nearly complete genome sequences with special emphasis on genomes of cyanobacteria, phototrophic eukaryotes, and anoxygenic phototrophic bacteria--invaluable for comparative genomic studies of energy and carbon metabolism in Synechocystis sp. PCC 6803. Aim 2. To develop the SEED's biological content in the form of a collection of encoded Subsystems largely covering the conserved cellular machinery in prokaryotes (and central metabolic machinery in eukaryotes). Aim 3. To develop, utilizing core SEED technology, the CyanoSEED--a specialized WEB portal for community-based annotation, and comparative analysis of all publicly available cyanobacterial genomes. Encode the set of additional subsystems representing key metabolic transformations in cyanobacteria and other photoautotrophs. We envisioned this resource as complementary to other public access databases for comparative genomic analysis currently available to the cyanobacterial research community. Aim 4. Perform in-depth analysis of several subsystems covering energy, carbon, and redox metabolism in the Synechocystis sp. PCC 6803 and all other cyanobacteria with available genome sequences. Reveal inconsistencies and gaps in the current knowledge of these subsystems. Use functional and genome context analysis tools in CyanoSEED to predict, whenever possible, candidate genes for inferred functional roles. To disseminate freely these conjectures and predictions by publishing

  8. Anaerobic Digestion: Process

    DEFF Research Database (Denmark)

    Angelidaki, Irini; Batstone, Damien J.

    2011-01-01

    with very little dry matter may also be called a digest. The digest should not be termed compost unless it specifically has been composted in an aerated step. This chapter describes the basic processes of anaerobic digestion. Chapter 9.5 describes the anaerobic treatment technologies, and Chapter 9...

  9. Anaerobic sludge granulation

    NARCIS (Netherlands)

    Hulshoff Pol, L.W.; Castro Lopes, de S.I.; Lettinga, G.; Lens, P.N.L.

    2004-01-01

    This paper reviews different theories on anaerobic sludge granulation in UASB-reactors that have been proposed during the past two decades
    This paper reviews different theories on anaerobic sludge granulation in UASB-reactors that have been proposed during the past two decades. The initial stage

  10. Aspects of Energy Metabolism in Mangalitsa Pigs Exposed at Thermic Neutral Temperature

    Directory of Open Access Journals (Sweden)

    Monica Pârvu

    2011-10-01

    Full Text Available The studies aimed the energy metabolism determination in Mangalitsa pigs exposed at thermic neutral temperature, compared to Large White pigs. The experimental period was between 80 and 100 kg liveweight. The animals had free access to standard, isoprotein and isocalory diets, with 13.5% crude protein (CP and 3100 kcal/kg metabolizable energy. Feed intake was measured on a daily basis. The energy-protein balance was calculated on the basis of comparative slaughter made at the beginning and end of the experiment. The metabolizable energy (MEc was estimated by chemical analysis (feed and excreta using mathematical modelling and the Whittemore’s formula. The metabolizable energy utilization efficiency was 0.61 at Large White and 0.53 at Mangalitsa.

  11. Signals for the lysosome: a control center for cellular clearance and energy metabolism

    OpenAIRE

    Settembre, Carmine; Fraldi, Alessandro; Medina, Diego L.; Ballabio, Andrea

    2013-01-01

    For a long time lysosomes were considered merely to be cellular “incinerators” involved in the degradation and recycling of cellular waste. However, there is now compelling evidence indicating that lysosomes have a much broader function and that they are involved in fundamental processes such as secretion, plasma membrane repair, signaling and energy metabolism. Furthermore, the essential role of lysosomes in the autophagic pathway puts these organelles at the crossroads of several cellular p...

  12. Effects of DGAT1 deficiency on energy and glucose metabolism are independent of adiponectin

    OpenAIRE

    Streeper, Ryan S.; Koliwad, Suneil K.; Villanueva, Claudio J.; Farese, Robert V

    2006-01-01

    Mice lacking acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1), an enzyme that catalyzes the terminal step in triacylglycerol synthesis, have enhanced insulin sensitivity and are protected from obesity, a result of increased energy expenditure. In these mice, factors derived from white adipose tissue (WAT) contribute to the systemic changes in metabolism. One such factor, adiponectin, increases fatty acid oxidation and enhances insulin sensitivity. To test the hypothesis that adiponectin is r...

  13. A Review of Effects of Heat Stress on Substance and Energy Metabolism in Muscle

    Institute of Scientific and Technical Information of China (English)

    Shiyong WU; Zhi FANG; Bo XUE; Longzhou LIU; Ye YANG

    2015-01-01

    Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress wil become more and more seri-ous. This paper reviewed the effects of heat stress on metabolism of proteins, glu-cose, fat and energy in skeletal muscle and related mechanisms so as to provide theoretical guidance for al eviating heat stress and improving production performance of animal suffering from heat stress.

  14. Ubc9 Impairs Activation of the Brown Fat Energy Metabolism Program in Human White Adipocytes.

    Science.gov (United States)

    Hartig, Sean M; Bader, David A; Abadie, Kathleen V; Motamed, Massoud; Hamilton, Mark P; Long, Weiwen; York, Brian; Mueller, Michaela; Wagner, Martin; Trauner, Michael; Chan, Lawrence; Bajaj, Mandeep; Moore, David D; Mancini, Michael A; McGuire, Sean E

    2015-09-01

    Insulin resistance and type 2 diabetes mellitus (T2DM) result from an inability to efficiently store and catabolize surplus energy in adipose tissue. Subcutaneous adipocytes protect against insulin resistance and T2DM by coupling differentiation with the induction of brown fat gene programs for efficient energy metabolism. Mechanisms that disrupt these programs in adipocytes are currently poorly defined, but represent therapeutic targets for the treatment of T2DM. To gain insight into these mechanisms, we performed a high-throughput microscopy screen that identified ubiquitin carrier protein 9 (Ubc9) as a negative regulator of energy storage in human sc adipocytes. Ubc9 depletion enhanced energy storage and induced the brown fat gene program in human sc adipocytes. Induction of adipocyte differentiation resulted in decreased Ubc9 expression commensurate with increased brown fat gene expression. Thiazolidinedione treatment reduced the interaction between Ubc9 and peroxisome proliferator-activated receptor (PPAR)γ, suggesting a mechanism by which Ubc9 represses PPARγ activity. In support of this hypothesis, Ubc9 overexpression remodeled energy metabolism in human sc adipocytes by selectively inhibiting brown adipocyte-specific function. Further, Ubc9 overexpression decreased uncoupling protein 1 expression by disrupting PPARγ binding at a critical uncoupling protein 1 enhancer region. Last, Ubc9 is significantly elevated in sc adipose tissue isolated from mouse models of insulin resistance as well as diabetic and insulin-resistant humans. Taken together, our findings demonstrate a critical role for Ubc9 in the regulation of sc adipocyte energy homeostasis.

  15. Postprandial Energy Metabolism in the Regulation of Body Weight: Is there a Mechanistic Role for Dietary Calcium?

    Directory of Open Access Journals (Sweden)

    Mario J. Soares

    2010-05-01

    Full Text Available There has been much interest in the mechanisms by which calcium may attenuate weight gain or accelerate body fat loss. This review focuses on postprandial energy metabolism and indicates that dietary calcium increases whole body fat oxidation after single and multiple meals. There is, as yet, no conclusive evidence for a greater diet induced thermogenesis, an increased lipolysis or suppression of key lipogenic enzyme systems. There is however convincing evidence that higher calcium intakes promote a modest energy loss through increased fecal fat excretion. Overall, there is a role for dietary calcium in human energy metabolism. Future studies need to define threshold intakes for metabolic and gastrointestinal outcomes.

  16. LGR4 and its role in intestinal protection and energy metabolism

    Directory of Open Access Journals (Sweden)

    Ziru eLi

    2015-08-01

    Full Text Available Leucine-rich repeat-containing G protein-coupled receptors (LGRs were identified by the unique nature of their long leucine-rich repeat extracellular domains. Distinct from classical G protein-coupled receptors which act via G proteins, LGR4 functions mainly through Wnt/β-catenin signaling to regulate cell proliferation, differentiation, and adult stem cell homeostasis. LGR4 is widely expressed in tissues ranging from the reproductive system, urinary system, sensory organs, digestive system, and the central nervous system, indicating LGR4 may have multiple functions in development. Here we focus on the digestive system by reviewing its effects on crypt cells differentiation and stem cells maintenance, which are important for cell regeneration after injury. Through effects on Wnt/β-catenin signaling and cell proliferation, LGR4 and its endogenous ligands, R-spondins, are involved in colon tumorigenesis. LGR4 also contributes to regulation of energy metabolism, including food intake, energy expenditure and lipid metabolism, as well as pancreatic β-cell proliferation and insulin secretion. This review summarizes the identification of LGR4, its endogenous ligand, ligand-receptor binding and intracellular signaling. Physiological functions include intestinal development and energy metabolism. The potential effects of LGR4 and its ligand in the treatment of inflammatory bowel disease, chemoradiotherapy induced gut damage, colorectal cancer and diabetes are also discussed.

  17. The Energy Metabolism in Caenorhabditis elegans under The Extremely Low-Frequency Electromagnetic Field Exposure

    Science.gov (United States)

    Shi, Zhenhua; Yu, Hui; Sun, Yongyan; Yang, Chuanjun; Lian, Huiyong; Cai, Peng

    2015-02-01

    A literal mountain of documentation generated in the past five decades showing unmistakable health hazards associated with extremely low-frequency electromagnetic fields (ELF-EMFs) exposure. However, the relation between energy mechanism and ELF-EMF exposure is poorly understood. In this study, Caenorhabditis elegans was exposed to 50 Hz ELF-EMF at intensities of 0.5, 1, 2, and 3 mT, respectively. Their metabolite variations were analyzed by GC-TOF/MS-based metabolomics. Although minimal metabolic variations and no regular pattern were observed, the contents of energy metabolism-related metabolites such as pyruvic acid, fumaric acid, and L-malic acid were elevated in all the treatments. The expressions of nineteen related genes that encode glycolytic enzymes were analyzed by using quantitative real-time PCR. Only genes encoding GAPDH were significantly upregulated (P elegans exposed to ELF-EMF have enhanced energy metabolism and restricted dietary, which might contribute to the resistance against exogenous ELF-EMF stress.

  18. Irradiation induced injury reduces energy metabolism in small intestine of Tibet minipigs.

    Directory of Open Access Journals (Sweden)

    Yu-Jue Wang

    Full Text Available BACKGROUND: The radiation-induced energy metabolism dysfunction related to injury and radiation doses is largely elusive. The purpose of this study is to investigate the early response of energy metabolism in small intestinal tissue and its correlation with pathologic lesion after total body X-ray irradiation (TBI in Tibet minipigs. METHODS AND RESULTS: 30 Tibet minipigs were assigned into 6 groups including 5 experimental groups and one control group with 6 animals each group. The minipigs in these experimental groups were subjected to a TBI of 2, 5, 8, 11, and 14 Gy, respectively. Small intestine tissues were collected at 24 h following X-ray exposure and analyzed by histology and high performance liquid chromatography (HPLC. DNA contents in this tissue were also examined. Irradiation causes pathologic lesions and mitochondrial abnormalities. The Deoxyribonucleic acid (DNA content-corrected and uncorrected adenosine-triphosphate (ATP and total adenine nucleotides (TAN were significantly reduced in a dose-dependent manner by 2-8 Gy exposure, and no further reduction was observed over 8 Gy. CONCLUSION: TBI induced injury is highly dependent on the irradiation dosage in small intestine and inversely correlates with the energy metabolism, with its reduction potentially indicating the severity of injury.

  19. A Single Oral Administration of Theaflavins Increases Energy Expenditure and the Expression of Metabolic Genes.

    Directory of Open Access Journals (Sweden)

    Naoto Kudo

    Full Text Available Theaflavins are polyphenols found in black tea, whose physiological activities are not well understood. This study on mice evaluated the influence of a single oral administration of theaflavins on energy metabolism by monitoring the initial metabolic changess in skeletal muscle and brown adipose tissue (BAT. Oxygen consumption (VO2 and energy expenditure (EE were increased significantly in mice treated with theaflavin rich fraction (TF compared with the group administered vehicle alone. There was no difference in locomotor activity. Fasting mice were euthanized under anesthesia before and 2 and 5, 20-hr after treatment with TF or vehicle. The mRNA levels of uncoupling protein-1 (UCP-1 and peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α in BAT were increased significantly 2-hr after administration ofTF. The levels of UCP-3 and PGC-1α in the gastrocnemius muscle were increased significantly 2 and 5-hr after administration of TF. The concentration of phosphorylated AMP-activated protein kinase (AMPK 1α was also increased significantly in the gastrocnemius 2 and 5-hr after treatment with TF. These results indicate that TF significantly enhances systemic energy expenditure, as evidenced by an increase in expression of metabolic genes.

  20. Energy transfer in "parasitic" cancer metabolism: mitochondria are the powerhouse and Achilles' heel of tumor cells.

    Science.gov (United States)

    Martinez-Outschoorn, Ubaldo E; Pestell, Richard G; Howell, Anthony; Tykocinski, Mark L; Nagajyothi, Fnu; Machado, Fabiana S; Tanowitz, Herbert B; Sotgia, Federica; Lisanti, Michael P

    2011-12-15

    It is now widely recognized that the tumor microenvironment promotes cancer cell growth and metastasis via changes in cytokine secretion and extracellular matrix remodeling. However, the role of tumor stromal cells in providing energy for epithelial cancer cell growth is a newly emerging paradigm. For example, we and others have recently proposed that tumor growth and metastasis is related to an energy imbalance. Host cells produce energy-rich nutrients via catabolism (through autophagy, mitophagy, and aerobic glycolysis), which are then transferred to cancer cells to fuel anabolic tumor growth. Stromal cell-derived L-lactate is taken up by cancer cells and is used for mitochondrial oxidative phosphorylation (OXPHOS) to produce ATP efficiently. However, "parasitic" energy transfer may be a more generalized mechanism in cancer biology than previously appreciated. Two recent papers in Science and Nature Medicine now show that lipolysis in host tissues also fuels tumor growth. These studies demonstrate that free fatty acids produced by host cell lipolysis are re-used via beta-oxidation (beta-OX) in cancer cell mitochondria. Thus, stromal catabolites (such as lactate, ketones, glutamine and free fatty acids) promote tumor growth by acting as high-energy onco-metabolites. As such, host catabolism, via autophagy, mitophagy and lipolysis, may explain the pathogenesis of cancer-associated cachexia and provides exciting new druggable targets for novel therapeutic interventions. Taken together, these findings also suggest that tumor cells promote their own growth and survival by behaving as a "parasitic organism." Hence, we propose the term "Parasitic Cancer Metabolism" to describe this type of metabolic coupling in tumors. Targeting tumor cell mitochondria (OXPHOS and beta-OX) would effectively uncouple tumor cells from their hosts, leading to their acute starvation. In this context, we discuss new evidence that high-energy onco-metabolites (produced by the stroma) can

  1. Endogenous and dietary lipids influencing feed intake and energy metabolism of periparturient dairy cows.

    Science.gov (United States)

    Kuhla, B; Metges, C C; Hammon, H M

    2016-07-01

    The high metabolic priority of the mammary gland for milk production, accompanied by limited feed intake around parturition results in a high propensity to mobilize body fat reserves. Under these conditions, fuel selection of many peripheral organs is switched, for example, from carbohydrate to fat utilization to spare glucose for milk production and to ensure partitioning of tissue- and dietary-derived nutrients toward the mammary gland. For example, muscle tissue uses nonesterified fatty acids (NEFA) but releases lactate and amino acids in a coordinated order, thereby providing precursors for milk synthesis or hepatic gluconeogenesis. Tissue metabolism and in concert, nutrient partitioning are controlled by the endocrine system involving a reduction in insulin secretion and systemic insulin sensitivity and orchestrated changes in plasma hormones such as insulin, adiponectin, insulin growth factor-I, growth hormone, glucagon, leptin, glucocorticoids, and catecholamines. However, the endocrine system is highly sensitive and responsive to an overload of fatty acids no matter if excessive NEFA supply originates from exogenous or endogenous sources. Feeding a diet containing rumen-protected fat from late lactation to calving and beyond exerts similar negative effects on energy intake, glucose and insulin concentrations as does a high extent of body fat mobilization around parturition in regard to the risk for ketosis and fatty liver development. High plasma NEFA concentrations are thought not to act directly at the brain level, but they increase the energy charge of the liver which is, signaled to the brain to diminish feed intake. Cows differing in fat mobilization during the transition phase differ in their hepatic energy charge, whole body fat oxidation, glucose metabolism, plasma ghrelin, and leptin concentrations and in feed intake several week before parturition. Hence, a high lipid load, no matter if stored, mobilized or fed, affects the endocrine system

  2. Endogenous and dietary lipids influencing feed intake and energy metabolism of periparturient dairy cows.

    Science.gov (United States)

    Kuhla, B; Metges, C C; Hammon, H M

    2016-07-01

    The high metabolic priority of the mammary gland for milk production, accompanied by limited feed intake around parturition results in a high propensity to mobilize body fat reserves. Under these conditions, fuel selection of many peripheral organs is switched, for example, from carbohydrate to fat utilization to spare glucose for milk production and to ensure partitioning of tissue- and dietary-derived nutrients toward the mammary gland. For example, muscle tissue uses nonesterified fatty acids (NEFA) but releases lactate and amino acids in a coordinated order, thereby providing precursors for milk synthesis or hepatic gluconeogenesis. Tissue metabolism and in concert, nutrient partitioning are controlled by the endocrine system involving a reduction in insulin secretion and systemic insulin sensitivity and orchestrated changes in plasma hormones such as insulin, adiponectin, insulin growth factor-I, growth hormone, glucagon, leptin, glucocorticoids, and catecholamines. However, the endocrine system is highly sensitive and responsive to an overload of fatty acids no matter if excessive NEFA supply originates from exogenous or endogenous sources. Feeding a diet containing rumen-protected fat from late lactation to calving and beyond exerts similar negative effects on energy intake, glucose and insulin concentrations as does a high extent of body fat mobilization around parturition in regard to the risk for ketosis and fatty liver development. High plasma NEFA concentrations are thought not to act directly at the brain level, but they increase the energy charge of the liver which is, signaled to the brain to diminish feed intake. Cows differing in fat mobilization during the transition phase differ in their hepatic energy charge, whole body fat oxidation, glucose metabolism, plasma ghrelin, and leptin concentrations and in feed intake several week before parturition. Hence, a high lipid load, no matter if stored, mobilized or fed, affects the endocrine system

  3. Thermodynamics-based design of microbial cell factories for anaerobic product formation.

    Science.gov (United States)

    Cueto-Rojas, Hugo F; van Maris, A J A; Wahl, S Aljoscha; Heijnen, J J

    2015-09-01

    The field of metabolic engineering has delivered new microbial cell factories and processes for the production of different compounds including biofuels, (di)carboxylic acids, alcohols, and amino acids. Most of these processes are aerobic, with few exceptions (e.g., alcoholic fermentation), and attention is focused on assembling a high-flux product pathway with a production limit usually set by the oxygen transfer rate. By contrast, anaerobic product synthesis offers significant benefits compared to aerobic systems: higher yields, less heat generation, reduced biomass production, and lower mechanical energy input, which can significantly reduce production costs. Using simple thermodynamic calculations, we demonstrate that many products can theoretically be produced under anaerobic conditions using several conventional and non-conventional substrates.

  4. Effect of short-term thyroxine administration on energy metabolism and mitochondrial efficiency in humans.

    Directory of Open Access Journals (Sweden)

    Darcy L Johannsen

    Full Text Available The physiologic effects of triiodothyronine (T3 on metabolic rate are well-documented; however, the effects of thyroxine (T4 are less clear despite its wide-spread use to treat thyroid-related disorders and other non-thyroidal conditions. Here, we investigated the effects of acute (3-day T4 supplementation on energy expenditure at rest and during incremental exercise. Furthermore, we used a combination of in situ and in vitro approaches to measure skeletal muscle metabolism before and after T4 treatment. Ten healthy, euthyroid males were given 200 µg T4 (levothyroxine per day for 3 days. Energy expenditure was measured at rest and during exercise by indirect calorimetry, and skeletal muscle mitochondrial function was assessed by in situ ATP flux ((31P MRS and in vitro respiratory control ratio (RCR, state 3/state 4 rate of oxygen uptake using a Clark-type electrode before and after acute T4 treatment. Thyroxine had a subtle effect on resting metabolic rate, increasing it by 4% (p = 0.059 without a change in resting ATP demand (i.e., ATP flux of the vastus lateralis. Exercise efficiency did not change with T4 treatment. The maximal capacity to produce ATP (state 3 respiration and the coupled state of the mitochondria (RCR were reduced by approximately 30% with T4 (p = 0.057 and p = 0.04, respectively. Together, the results suggest that T4, although less metabolically active than T3, reduces skeletal muscle efficiency and modestly increases resting metabolism even after short-term supplementation. Our findings may be clinically relevant given the expanding application of T4 to treat non-thyroidal conditions such as obesity and weight loss.

  5. Effects of rutin and buckwheat seeds on energy metabolism and methane production in dairy cows.

    Science.gov (United States)

    Stoldt, Ann-Kathrin; Derno, Michael; Das, Gürbüz; Weitzel, Joachim M; Wolffram, Siegfried; Metges, Cornelia C

    2016-03-01

    Flavonoids are secondary plant metabolites with several health promoting effects. As dairy cows often suffer from metabolic imbalance and health problems, interest is growing in health improvements by plant substances such as flavonoids. Our group has recently shown that the flavonoids quercetin and rutin (a glucorhamnoside of quercetin) are bioavailable in cows when given via a duodenal fistula or orally, respectively, affect glucose metabolism, and have beneficial effects on liver health. Furthermore, flavonoids may reduce rumen methane production in vitro through their antibacterial properties. To test the hypothesis that rutin has effects on energy metabolism, methane production, and production performance in dairy cows, we fed rutin trihydrate at a dose of 100mg/kg of body weight to a group of 7 lactating dairy cows for 2 wk in a crossover design. In a second experiment, 2 cows were fed the same ration but were supplemented with buckwheat seeds (Fagopyrum tartaricum), providing rutin at a dose comparable to the first experiment. Two other cows receiving barley supplements were used as controls in a change-over mode. Blood samples were taken weekly and respiration measurements were performed at the end of each treatment. Supplementation of pure rutin, but not of rutin contained in buckwheat seeds, increased the plasma quercetin content. Methane production and milk yield and composition were not affected by rutin treatment in either form. Plasma glucose, β-hydroxybutyrate, and albumin were increased by pure rutin treatment, indicating a possible metabolic effect of rutin on energy metabolism of dairy cows. In addition, we did not show that in vivo ruminal methane production was reduced by rutin. In conclusion, we could not confirm earlier reports on in vitro methane reduction by rutin supplementation in dairy cows in established lactation.

  6. Energy substrate metabolism among habitually violent alcoholic offenders having antisocial personality disorder.

    Science.gov (United States)

    Virkkunen, Matti; Rissanen, Aila; Naukkarinen, Hannu; Franssila-Kallunki, Anja; Linnoila, Markku; Tiihonen, Jari

    2007-04-15

    A large proportion of violent offences in Western countries are attributable to antisocial personality disorder (APD). Several studies have shown abnormal lipid, carbohydrate and low cerebrospinal fluid (CSF) monoamine metabolite levels in habitually violent alcoholic offenders with APD, but it is not clear how these biochemical abnormalities are related to each other in this disorder. We aimed to study energy substrate metabolism among habitually violent offenders with APD. Insulin sensitivity (euglycemic insulin clamp), basal energy expenditure (indirect calorimetry), and CSF 5-hydroxyindoleacetic acid (5-HIAA) measurements were performed on 96 habitually violent antisocial male alcoholic offenders and on 40 normal male controls. Habitually violent, incarcerated offenders with APD had significantly lower non-oxidative glucose metabolism, basal glucagon, and free fatty acids when compared with normal controls, but glucose oxidation and CSF 5-HIAA did not differ markedly between these groups. The effect sizes for lower non-oxidative glucose metabolism among incarcerated and non-incarcerated APD subjects were 0.73 and 0.51, respectively, when compared with controls, indicating that this finding was not explained by incarceration. Habitually violent offenders with APD have markedly lower glucagon and non-oxidative glucose metabolism when compared with healthy controls, and these findings were more strongly associated with habitual violent offending than low CSF 5-HIAA levels, a well-established marker for impulsive violent behavior. Follow-up studies are needed to confirm if abnormal glucose and lipid metabolism can be used to predict violent offending over the course of the APD offender's life span. PMID:17316826

  7. Effects of rutin and buckwheat seeds on energy metabolism and methane production in dairy cows.

    Science.gov (United States)

    Stoldt, Ann-Kathrin; Derno, Michael; Das, Gürbüz; Weitzel, Joachim M; Wolffram, Siegfried; Metges, Cornelia C

    2016-03-01

    Flavonoids are secondary plant metabolites with several health promoting effects. As dairy cows often suffer from metabolic imbalance and health problems, interest is growing in health improvements by plant substances such as flavonoids. Our group has recently shown that the flavonoids quercetin and rutin (a glucorhamnoside of quercetin) are bioavailable in cows when given via a duodenal fistula or orally, respectively, affect glucose metabolism, and have beneficial effects on liver health. Furthermore, flavonoids may reduce rumen methane production in vitro through their antibacterial properties. To test the hypothesis that rutin has effects on energy metabolism, methane production, and production performance in dairy cows, we fed rutin trihydrate at a dose of 100mg/kg of body weight to a group of 7 lactating dairy cows for 2 wk in a crossover design. In a second experiment, 2 cows were fed the same ration but were supplemented with buckwheat seeds (Fagopyrum tartaricum), providing rutin at a dose comparable to the first experiment. Two other cows receiving barley supplements were used as controls in a change-over mode. Blood samples were taken weekly and respiration measurements were performed at the end of each treatment. Supplementation of pure rutin, but not of rutin contained in buckwheat seeds, increased the plasma quercetin content. Methane production and milk yield and composition were not affected by rutin treatment in either form. Plasma glucose, β-hydroxybutyrate, and albumin were increased by pure rutin treatment, indicating a possible metabolic effect of rutin on energy metabolism of dairy cows. In addition, we did not show that in vivo ruminal methane production was reduced by rutin. In conclusion, we could not confirm earlier reports on in vitro methane reduction by rutin supplementation in dairy cows in established lactation. PMID:26805964

  8. Alpha proteobacterial ancestry of the [Fe-Fe]-hydrogenases in anaerobic eukaryotes

    DEFF Research Database (Denmark)

    Degli Esposti, Mauro; Cortez, Diego; Lozano, Luis;

    2016-01-01

    . The consensus is based upon genetic and metabolic similarities between mitochondria and aerobic α proteobacteria but fails to explain the origin of several enzymes found in the mitochondria-derived organelles of anaerobic eukaryotes such as Trichomonas and Entamoeba. These enzymes are thought to derive from...... bacterial lineages other than a proteobacteria, e.g., Clostridium - an obligate anaerobe. [FeFe]-hydrogenase constitues the characteristic enzyme of this anaerobic metabolism and is present in different types also in Entamoeba and other anaerobic eukaryotes. Here we show that a proteobacteria derived from...

  9. Predicting changes of body weight, body fat, energy expenditure and metabolic fuel selection in C57BL/6 mice.

    Directory of Open Access Journals (Sweden)

    Juen Guo

    Full Text Available The mouse is an important model organism for investigating the molecular mechanisms of body weight regulation, but a quantitative understanding of mouse energy metabolism remains lacking. Therefore, we created a mathematical model of mouse energy metabolism to predict dynamic changes of body weight, body fat, energy expenditure, and metabolic fuel selection. Based on the principle of energy balance, we constructed ordinary differential equations representing the dynamics of body fat mass (FM and fat-free mass (FFM as a function of dietary intake and energy expenditure (EE. The EE model included the cost of tissue deposition, physical activity, diet-induced thermogenesis, and the influence of FM and FFM on metabolic rate. The model was calibrated using previously published data and validated by comparing its predictions to measurements in five groups of male C57/BL6 mice (N = 30 provided ad libitum access to either chow or high fat diets for varying time periods. The mathematical model accurately predicted the observed body weight and FM changes. Physical activity was predicted to decrease immediately upon switching from the chow to the high fat diet and the model coefficients relating EE to FM and FFM agreed with previous independent estimates. Metabolic fuel selection was predicted to depend on a complex interplay between diet composition, the degree of energy imbalance, and body composition. This is the first validated mathematical model of mouse energy metabolism and it provides a quantitative framework for investigating energy balance relationships in mouse models of obesity and diabetes.

  10. Changes in energy metabolism in response to 48 h of overfeeding and fasting in Caucasians and Pima Indians

    DEFF Research Database (Denmark)

    Weyer, C; Vozarova, B; Ravussin, E;

    2001-01-01

    Differences in the metabolic response to overfeeding and starvation may confer susceptibility or resistance to obesity in humans. To further examine this hypothesis, we assessed the changes in 24 h energy metabolism in response to short-term overfeeding and fasting in Caucasians (C) and Pima Indi...

  11. Possible therapeutic effect of naftidrofuryl oxalate on brain energy metabolism after microsphere-induced cerebral embolism.

    OpenAIRE

    Miyake, K.; Tanonaka, K; Minematsu, R.; Inoue, K.; Takeo, S.

    1989-01-01

    1. The present study was designed to determine whether naftidrofuryl oxalate exerts a possible therapeutic effect on brain energy metabolism impaired by microsphere-induced cerebral embolism in vitro. 2. Injection of microspheres into the right carotid canal resulted in a decrease in tissue high-energy phosphates both in the right and left hemispheres, and an increase in tissue lactate in the right hemisphere, on the 3rd and the 5th day after the embolism. The embolism also induced a marked r...

  12. Economic Feasibility of Stand-Alone Wind Energy Hybrid with Bioenergy from Anaerobic Digestion for Electrification of Remote Area of Pakistan

    Directory of Open Access Journals (Sweden)

    Abdur Raheem

    2015-02-01

    Full Text Available Hybrid Renewable Energy systems (HRES are gaining importance throughout the world because of the finite sources of oil and gas reservoirs. These have the great ability in the production of electrical energy and cleaning the environment. It is difficult to get grid electricity in the remote areas where no infrastructure exists. The utilization of renewable sources is the ultimate solution for the generation of electricity. In this paper, the economic modeling of Hybrid system consisting of Wind/biomass is explored for the remote area ‘Jangiah’ of Balochistan province, Pakistan. Anaerobic Digestion of biomass is used to get biogas. This source is used to complement the uncertainties in the wind production. Homer is used to simulate the hybrid model. Economic analysis is performed to get the net present value (NPV and cost of energy. It is observed that wind/biomass alone is capable to meet the demand of community which consumes 60 kW peak daily along with the storage backup. This system is the most economical with COE equal to 0.118 US$/kWh following the hybrid biomass/wind/diesel system with COE 0.202 US$/kWh. The sensitivity analysis is carried out and shows that the proposed system is sensitive to the prices of fossil fuel and project lifespan. The net present value increases as the lifetime of the project increases from 15 years to 30 years. It can also be concluded that if the price of the diesel drops below 0.8 US$/liter, the traditional system using fossil fuels will become the most suitable system for the generation of electricity in remote areas.

  13. Identification and characterization of an anaerobic ethanol-producing cellulolytic bacterial consortium from Great Basin hot springs with agricultural residues and energy crops.

    Science.gov (United States)

    Zhao, Chao; Deng, Yunjin; Wang, Xingna; Li, Qiuzhe; Huang, Yifan; Liu, Bin

    2014-09-01

    In order to obtain the cellulolytic bacterial consortia, sediments from Great Basin hot springs (Nevada, USA) were sampled and enriched with cellulosic biomass as the sole carbon source. The bacterial composition of the resulting anaerobic ethanol-producing celluloytic bacterial consortium, named SV79, was analyzed. With methods of the full-length 16S rRNA librarybased analysis and denaturing gradient gel electrophoresis, 21 bacteria belonging to eight genera were detected from this consortium. Clones with closest relation to the genera Acetivibrio, Clostridium, Cellulosilyticum, Ruminococcus, and Sporomusa were predominant. The cellulase activities and ethanol productions of consortium SV79 using different agricultural residues (sugarcane bagasse and spent mushroom substrate) and energy crops (Spartina anglica, Miscanthus floridulus, and Pennisetum sinese Roxb) were studied. During cultivation, consortium SV79 produced the maximum filter paper activity (FPase, 9.41 U/ml), carboxymethylcellulase activity (CMCase, 6.35 U/ml), and xylanase activity (4.28 U/ml) with sugarcane bagasse, spent mushroom substrate, and S. anglica, respectively. The ethanol production using M. floridulus as substrate was up to 2.63 mM ethanol/g using gas chromatography analysis. It has high potential to be a new candidate for producing ethanol with cellulosic biomass under anoxic conditions in natural environments.

  14. Anaerobic digestion in sustainable biomass chains

    NARCIS (Netherlands)

    Pabon Pereira, C.P.

    2009-01-01

    This thesis evaluates the potential contribution of anaerobic digestion (AD) to the sustainability of biomass chains. Results provide insights in the technological potential to recover energy and valuable by-products from energy crops and residues, and evaluate biomass cascades involving AD technolo

  15. Microalgal bioengineering for sustainable energy development: Recent transgenesis and metabolic engineering strategies.

    Science.gov (United States)

    Banerjee, Chiranjib; Singh, Puneet Kumar; Shukla, Pratyoosh

    2016-03-01

    Exploring the efficiency of algae to produce remarkable products can be directly benefitted by studying its mechanism at systems level. Recent advents in biotechnology like flux balance analysis (FBA), genomics and in silico proteomics minimize the wet lab exertion. It is understood that FBA predicts the metabolic products, metabolic pathways and alternative pathway to maximize the desired product, and these are key components for microalgae bio-engineering. This review encompasses recent transgenesis techniques and metabolic engineering strategies applied to different microalgae for improving different traits. Further it also throws light on RNAi and riboswitch engineering based methods which may be advantageous for high throughput microalgal research. A valid and optimally designed microalga can be developed where every engineering strategies meet each other successfully and will definitely fulfill the market needs. It is also to be noted that Omics (viz. genetic and metabolic manipulation with bioinformatics) should be integrated to develop a strain which could prove to be a futuristic solution for sustainable development for energy. PMID:26844808

  16. A conserved role for syndecan family members in the regulation of whole-body energy metabolism.

    Directory of Open Access Journals (Sweden)

    Maria De Luca

    Full Text Available Syndecans are a family of type-I transmembrane proteins that are involved in cell-matrix adhesion, migration, neuronal development, and inflammation. Previous quantitative genetic studies pinpointed Drosophila Syndecan (dSdc as a positional candidate gene affecting variation in fat storage between two Drosophila melanogaster strains. Here, we first used quantitative complementation tests with dSdc mutants to confirm that natural variation in this gene affects variability in Drosophila fat storage. Next, we examined the effects of a viable dSdc mutant on Drosophila whole-body energy metabolism and associated traits. We observed that young flies homozygous for the dSdc mutation had reduced fat storage and slept longer than homozygous wild-type flies. They also displayed significantly reduced metabolic rate, lower expression of spargel (the Drosophila homologue of PGC-1, and reduced mitochondrial respiration. Compared to control flies, dSdc mutants had lower expression of brain insulin-like peptides, were less fecund, more sensitive to starvation, and had reduced life span. Finally, we tested for association between single nucleotide polymorphisms (SNPs in the human SDC4 gene and variation in body composition, metabolism, glucose homeostasis, and sleep traits in a cohort of healthy early pubertal children. We found that SNP rs4599 was significantly associated with resting energy expenditure (P = 0.001 after Bonferroni correction and nominally associated with fasting glucose levels (P = 0.01 and sleep duration (P = 0.044. On average, children homozygous for the minor allele had lower levels of glucose, higher resting energy expenditure, and slept shorter than children homozygous for the common allele. We also observed that SNP rs1981429 was nominally associated with lean tissue mass (P = 0.035 and intra-abdominal fat (P = 0.049, and SNP rs2267871 with insulin sensitivity (P = 0.037. Collectively, our results in Drosophila and humans argue that

  17. Rhabdomyosarcoma cells show an energy producing anabolic metabolic phenotype compared with primary myocytes

    Directory of Open Access Journals (Sweden)

    Higashi Richard M

    2008-10-01

    Full Text Available Abstract Background The functional status of a cell is expressed in its metabolic activity. We have applied stable isotope tracing methods to determine the differences in metabolic pathways in proliferating Rhabdomysarcoma cells (Rh30 and human primary myocytes in culture. Uniformly 13C-labeled glucose was used as a source molecule to follow the incorporation of 13C into more than 40 marker metabolites using NMR and GC-MS. These include metabolites that report on the activity of glycolysis, Krebs' cycle, pentose phosphate pathway and pyrimidine biosynthesis. Results The Rh30 cells proliferated faster than the myocytes. Major differences in flux through glycolysis were evident from incorporation of label into secreted lactate, which accounts for a substantial fraction of the glucose carbon utilized by the cells. Krebs' cycle activity as determined by 13C isotopomer distributions in glutamate, aspartate, malate and pyrimidine rings was considerably higher in the cancer cells than in the primary myocytes. Large differences were also evident in de novo biosynthesis of riboses in the free nucleotide pools, as well as entry of glucose carbon into the pyrimidine rings in the free nucleotide pool. Specific labeling patterns in these metabolites show the increased importance of anaplerotic reactions in the cancer cells to maintain the high demand for anabolic and energy metabolism compared with the slower growing primary myocytes. Serum-stimulated Rh30 cells showed higher degrees of labeling than serum starved cells, but they retained their characteristic anabolic metabolism profile. The myocytes showed evidence of de novo synthesis of glycogen, which was absent in the Rh30 cells. Conclusion The specific 13C isotopomer patterns showed that the major difference between the transformed and the primary cells is the shift from energy and maintenance metabolism in the myocytes toward increased energy and anabolic metabolism for proliferation in the Rh30 cells

  18. Mechanisms controlling pork quality development: The biochemistry controlling postmortem energy metabolism.

    Science.gov (United States)

    Scheffler, T L; Gerrard, D E

    2007-09-01

    Pale, soft and exudative (PSE) pork represents considerable economic losses for the industry due to its limited functionality and undesirable appearance. During the past several decades, exhaustive research covering various aspects of the food chain has established genotyping procedures, recommended handling practices, and quality indicators in order to reduce the incidence of inferior pork quality. Despite these efforts, there is still a relatively high occurrence of PSE pork. Development of pork quality attributes is largely governed by the rate and extent of postmortem pH decline. The combination of high temperature at low pH or abnormally low ultimate pH causes denaturation of sarcoplasmic and myofibrillar proteins, resulting in paler color and reduced water holding capacity. The pH decline is closely related to muscle energy availability and demand at or around slaughter. The postmortem degradation of glycogen through glycogenolysis and glycolysis provides ATP to help meet energy demand and decreases pH by generating lactate and H+. Therefore, the flux of metabolites through glycolysis, the involvement of energy signaling pathways that modulate glycolytic activity, and the inherent metabolism of different fiber types are critical factors influencing pH decline and pork quality. Further, recent work implicates adenosine monophosphate-activated protein kinase (AMPK) as a major energy sensor for the cell, and thus may be involved in the control of postmortem metabolism. The intent of this paper is to review the biochemistry controlling postmortem energy metabolism in pig muscle and explore new information generated using genetic mutations in order to define the fundamental mechanisms controlling the transformation of muscle to meat. PMID:22061391

  19. Metabolic consequences of resistive-type exercise

    Science.gov (United States)

    Dudley, G. A.

    1988-01-01

    This brief review concerns acute and chronic metabolic responses to resistive-type exercise (RTE) (i.e., Olympic/power weight lifting and bodybuilding). Performance of RTE presents power output substantially greater (10-15-fold) than that evident with endurance-type exercise. Accordingly, RTE relies heavily on the anaerobic enzyme machinery of skeletal muscle for energy supply, with alterations in the rate of aerobic metabolism being modest. Hydrolysis of high energy phosphate compounds (PC, ATP), glycogenolysis, and glycolysis are evident during an acute bout of RTE as indicated by metabolic markers in mixed fiber type skeletal muscle samples. The type of RTE probably influences the magnitude of these responses since the increase in blood lactate is much greater during a typical "bodybuilding" than "power lifting" session. The influence of RTE training on acute metabolic responses to RTE has received little attention. An individual's inherent metabolic characteristics are apparently sufficient to meet the energy demands of RTE as training of this type does not increase VO2max or substantially alter the content of marker enzymes in mixed fiber type skeletal muscle. Analyses of pools of fast- vs slow-twitch fibers, however, indicate that RTE-induced changes may be fiber type specific. Future studies should better delineate the metabolic responses to RTE and determine whether these are related to the enhanced performance associated with such training.

  20. Evaluation of mild hypothermia therapy for neonatal hypoxic-ischaemic encephalopathy on brain energy metabolism using 18F-fluorodeoxyglucose positron emission computed tomography

    OpenAIRE

    Luo, Mei; Li, Qingping; DONG, WENBIN; Zhai, Xuesong; Kang, Lan

    2014-01-01

    It remains unclear whether mild hypothermia affects energy metabolism in the brain tissue of newborns with hypoxic-ischaemic encephalopathy (HIE). The current study aimed to investigate the effect of mild hypothermia on energy metabolism in neonatal HIE and assess brain energy metabolism using position emission tomography/computed tomography (PET/CT) scanning. The mean standardised uptake values of 18F-fluorodeoxyglucose (18F-FDG) were used to determine the glucose metabolic rate in various b...

  1. Fluvoxamine alters the activity of energy metabolism enzymes in the brain

    Directory of Open Access Journals (Sweden)

    Gabriela K. Ferreira

    2014-09-01

    Full Text Available Objective: Several studies support the hypothesis that metabolism impairment is involved in the pathophysiology of depression and that some antidepressants act by modulating brain energy metabolism. Thus, we evaluated the activity of Krebs cycle enzymes, the mitochondrial respiratory chain, and creatine kinase in the brain of rats subjected to prolonged administration of fluvoxamine. Methods: Wistar rats received daily administration of fluvoxamine in saline (10, 30, and 60 mg/kg for 14 days. Twelve hours after the last administration, rats were killed by decapitation and the prefrontal cortex, cerebral cortex, hippocampus, striatum, and cerebellum were rapidly isolated. Results: The activities of citrate synthase, malate dehydrogenase, and complexes I, II-III, and IV were decreased after prolonged administration of fluvoxamine in rats. However, the activities of complex II, succinate dehydrogenase, and creatine kinase were increased. Conclusions: Alterations in activity of energy metabolism enzymes were observed in most brain areas analyzed. Thus, we suggest that the decrease in citrate synthase, malate dehydrogenase, and complexes I, II-III, and IV can be related to adverse effects of pharmacotherapy, but long-term molecular adaptations cannot be ruled out. In addition, we demonstrated that these changes varied according to brain structure or biochemical analysis and were not dose-dependent.

  2. Depletion of reduction potential and key energy generation metabolic enzymes underlies tellurite toxicity in Deinococcus radiodurans.

    Science.gov (United States)

    Anaganti, Narasimha; Basu, Bhakti; Gupta, Alka; Joseph, Daisy; Apte, Shree Kumar

    2015-01-01

    Oxidative stress resistant Deinococcus radiodurans surprisingly exhibited moderate sensitivity to tellurite induced oxidative stress (LD50 = 40 μM tellurite, 40 min exposure). The organism reduced 70% of 40 μM potassium tellurite within 5 h. Tellurite exposure significantly modulated cellular redox status. The level of ROS and protein carbonyl contents increased while the cellular reduction potential substantially decreased following tellurite exposure. Cellular thiols levels initially increased (within 30 min) of tellurite exposure but decreased at later time points. At proteome level, tellurite resistance proteins (TerB and TerD), tellurite reducing enzymes (pyruvate dehydrogense subunits E1 and E3), ROS detoxification enzymes (superoxide dismutase and thioredoxin reductase), and protein folding chaperones (DnaK, EF-Ts, and PPIase) displayed increased abundance in tellurite-stressed cells. However, remarkably decreased levels of key metabolic enzymes (aconitase, transketolase, 3-hydroxy acyl-CoA dehydrogenase, acyl-CoA dehydrogenase, electron transfer flavoprotein alpha, and beta) involved in carbon and energy metabolism were observed upon tellurite stress. The results demonstrate that depletion of reduction potential in intensive tellurite reduction with impaired energy metabolism lead to tellurite toxicity in D. radiodurans.

  3. Anaerobic Digestion and its Applications

    Science.gov (United States)

    Anaerobic digestion is a natural biological process. The initials "AD" may refer to the process of anaerobic digestion, or the built systems of anaerobic digesters. While there are many kinds of digesters, the biology is basically the same for all. Anaerobic digesters are built...

  4. Mechanotransduction in primary human osteoarthritic chondrocytes is mediated by metabolism of energy, lipids, and amino acids.

    Science.gov (United States)

    Zignego, Donald L; Hilmer, Jonathan K; June, Ronald K

    2015-12-16

    Chondrocytes are the sole cell type found in articular cartilage and are repeatedly subjected to mechanical loading in vivo. We hypothesized that physiological dynamic compression results in changes in energy metabolism to produce proteins for maintenance of the pericellular and extracellular matrices. The objective of this study was to develop an in-depth understanding for the short term (human chondrocytes harvested from femoral heads of osteoarthritic donors. Cell-seeded agarose constructs were randomly assigned to experimental groups, and dynamic compression was applied for 0, 15, or 30min. Following dynamic compression, metabolites were extracted and detected by HPLC-MS. Untargeted analyzes examined changes in global metabolomics profiles and targeted analysis examined the expression of specific metabolites related to central energy metabolism. We identified hundreds of metabolites that were regulated by applied compression, and we report the detection of 16 molecules not found in existing metabolite databases. We observed patient-specific mechanotransduction with aging dependence. Targeted studies found a transient increase in the ratio of NADP+ to NADPH and an initial decrease in the ratio of GDP to GTP, suggesting a flux of energy into the TCA cycle. By characterizing metabolomics profiles of primary chondrocytes in response to applied dynamic compression, this study provides insight into how OA chondrocytes respond to mechanical load. These results are consistent with increases in glycolytic energy utilization by mechanically induced signaling, and add substantial new data to a complex picture of how chondrocytes transduce mechanical loads.

  5. Influence of Continuous Flow Microwave Pre-Treatment on Anaerobic Digestion of Secondary Thickened Sludge for Sustainable Energy Recovery in Sewage Treatment Plant

    Science.gov (United States)

    Hephzibah, D.; Kumaran, P.; Saifuddin, N. M.

    2016-03-01

    This work elucidates the effects of pre-treatment of secondary thickened sludge (STS) for enhancement of biogas production that has great potential to generate energy for the utilization of the sewage treatment plant (STP) itself. Microwave pre-treatment has been adopted for this study. Experiment works have been designed and conducted to examine the effectiveness of continuous flow microwave pre-treatment on the solubility of STS, digestibility of STS and biogas production at a power level of 80 W for 5, 10 and 15 minutes. A few characteristics of the sewage sludge were monitored daily to identify the effect of pre-treatment on the sludge. The soluble chemical oxygen demand (SCOD)/total chemical oxygen demand (TCOD) ratio increased by 0.1, 1.0 and 1.8%, while the volatile fatty acids (VFA) concentration of the pre-treated sludge improved by 4.4, 5.1, 5.9% at the irradiation time of 5, 10 and 15 minutes, respectively at a microwave power level of 80 W. Besides that, the digestate also indicates that the pre-treated sludge undergoes efficient VS removal and TCOD removal after anaerobic digestion compared to the untreated sludge. Moreover, the biogas quantity increased by an average of 19.2, 24.1 and 32.2% in 5, 10 and 15 minutes irradiation time respectively compared to the untreated sludge. The additional quantity of biogas generated has shown a great potential for sustainable energy generation that can be utilized internally by the STP.

  6. Metabolomic analysis of amino acid and energy metabolism in rats supplemented with chlorogenic acid

    Science.gov (United States)

    Ruan, Zheng; Yang, Yuhui; Zhou, Yan; Wen, Yanmei; Ding, Sheng; Liu, Gang; Wu, Xin; Deng, Zeyuan; Assaad, Houssein; Wu, Guoyao

    2016-01-01

    This study was conducted to investigate effects of chlorogenic acid (CGA) supplementation on serum and hepatic metabolomes in rats. Rats received daily intragastric administration of either CGA (60 mg/kg body weight) or distilled water (control) for 4 weeks. Growth performance, serum biochemical profiles, and hepatic morphology were measured. Additionally, serum and liver tissue extracts were analyzed for metabolomes by high-resolution 1H nuclear magnetic resonance-based metabolomics and multivariate statistics. CGA did not affect rat growth performance, serum biochemical profiles, or hepatic morphology. However, supplementation with CGA decreased serum concentrations of lactate, pyruvate, succinate, citrate, β-hydroxybutyrate and acetoacetate, while increasing serum concentrations of glycine and hepatic concentrations of glutathione. These results suggest that CGA supplementation results in perturbation of energy and amino acid metabolism in rats. We suggest that glycine and glutathione in serum may be useful biomarkers for biological properties of CGA on nitrogen metabolism in vivo. PMID:24927697

  7. Bone morphogenetic proteins in inflammation, glucose homeostasis and adipose tissue energy metabolism

    DEFF Research Database (Denmark)

    Grgurevic, Lovorka; Christensen, Gitte Lund; Schulz, Tim J;

    2016-01-01

    implicated in pancreas development as well as control of adult glucose homeostasis. Lastly, we review the recently recognized role of BMPs in brown adipose tissue formation and their consequences for energy expenditure and adiposity. In summary, BMPs play a pivotal role in metabolism beyond their role...... homeostasis (anaemia, hemochromatosis) and oxidative damage. The second and third parts of this review focus on BMPs in the development of metabolic pathologies such as type-2 diabetes mellitus and obesity. The pancreatic beta cells are the sole source of the hormone insulin and BMPs have recently been...... in skeletal homeostasis. However, increased understanding of these pleiotropic functions also highlights the necessity of tissue-specific strategies when harnessing BMP action as a therapeutic target....

  8. Simulating antler growth and energy, nitrogen, calcium and phosphorus metabolism in caribou

    Directory of Open Access Journals (Sweden)

    Ron Moen

    1998-03-01

    Full Text Available We added antler growth and mineral metabolism modules to a previously developed energetics model for ruminants to simulate energy and mineral balance of male and female caribou throughout an annual cycle. Body watet, fat, protein, and ash are monitored on a daily time step, and energy costs associated with reproduction and body mass changes are simulated. In order to simulate antler growth, we had to predict calcium and phosphorus metabolism as it is affected by antler growth, gestation, and lactation. We used data on dietary digestibility, protein, calcium and phosphorus content, and seasonal patterns in body mass to predict the energy, nitrogen, calcium, and phosphorus balances of a "generic" male and female caribou. Antler growth in males increased energy requirements during antler growth by 8 to 16%, depending on the efficiency with which energy was used for antler growth. Female energy requirements for antler growth were proportionately much smaller because of the smaller size of female antlers. Protein requirements for antler growth in both males and females were met by forage intake. Calcium and phosphorus must be resorbed from bone during peak antler growth in males, when > 25 g/day of calcium and > 12 g/day of phosphorus are being deposited in antlers. Females are capable of meeting calcium needs during antler growth without bone resorption, but phosphorus was resorbed from bone during the final stages of antler mineralization. After energy, phosphorus was most likely to limit growth of antlers for both males and females in our simulations. Input parameters can be easily changed to represent caribou from specific geographic regions in which dietary nutrient content or body mass patterns differ from those in our "generic" caribou. The model can be used to quantitatively analyze the evolutionary basis for development of antlers in female caribou, and the relationship between body mass and antler size in the Cervidae.

  9. Reconstitution of supramolecular organization involved in energy metabolism at electrochemical interfaces for biosensing and bioenergy production.

    Science.gov (United States)

    Roger, M; de Poulpiquet, A; Ciaccafava, A; Ilbert, M; Guiral, M; Giudici-Orticoni, M T; Lojou, E

    2014-02-01

    How the redox proteins and enzymes involved in bioenergetic pathways are organized is a relevant fundamental question, but our understanding of this is still incomplete. This review provides a critical examination of the electrochemical tools developed in recent years to obtain knowledge of the intramolecular and intermolecular electron transfer processes involved in metabolic pathways. Furthermore, better understanding of the electron transfer processes associated with energy metabolism will provide the basis for the rational design of biotechnological devices such as electrochemical biosensors, enzymatic and microbial fuel cells, and hydrogen production factories. Starting from the redox complexes involved in two relevant bacterial chains, i.e., from the hyperthermophile Aquifex aeolicus and the acidophile Acidithiobacillus ferrooxidans, examination of protein-protein interactions using electrochemistry is first reviewed, with a focus on the orientation of a protein on an electrochemical interface mimic of a physiological interaction between two partners. Special attention is paid to current research in the electrochemistry of essential membrane proteins, which is one mandatory step toward the understanding of energy metabolic pathways. The complex and challenging architectures built to reconstitute a membrane-like environment at an electrode are especially considered. The role played by electrochemistry in the attempt to consider full bacterial metabolism is finally emphasized through the study of whole cells immobilized at electrodes as suspensions or biofilms. Before the performances of biotechnological devices can be further improved to make them really attractive, questions remain to be addressed in this particular field of research. We discuss the bottlenecks that need to be overcome in the future. PMID:24292430

  10. The Characteristic of Energy Metabolism and Nutritional Supplement of Volleyball Athletes

    Directory of Open Access Journals (Sweden)

    Liping Zhang

    2015-05-01

    Full Text Available Substantial metabolism and energy metabolism is the base of the normal operation for every organ. Nutrition arrangement instructed by the knowledge about the regularities of metabolism is very significant. The purpose of the presented study was the examination of nutrition intake influence on energy metabolism in young volleyball players. The study was performed in twenty four 16-18 years old male volleyball players in the competition period. Subjects were divided into 2 groups, depending on the calcium intake: more than 1300 mg/day in the first group (13 athletes; and less than 1300 mg/day in the second group (11 athletes. The nutrition mode assessment was based on the 24-h dietary history using the recall method. In the blood serum concentrations of osteocalcin, alkaline phosphatase (bALP, C-terminal telopeptide of collagen I (ICTP, insulin-like growth factor-1 (IGF-1, insulin-like-growth factor-binding protein-3 (IGFBP-3, growth hormone (hGH and ionized calcium and magnesium were determined. Statistical analysis showed significant differences between both groups investigated in respect to the calcium (p<0.01 and protein (p<0.05 intake and the bALP and (IGFBP-3 concentrations (p<0.05. The results of the study led us to conclude that low calcium and protein intake together with systematic sport activity negatively influenced the bone formation level. At last to improve the capacity of sports man we give some advice such as the methods of volleyball train and supplying some nutrient matter in the training.

  11. Who controls the ATP supply in cancer cells? Biochemistry lessons to understand cancer energy metabolism.

    Science.gov (United States)

    Moreno-Sánchez, Rafael; Marín-Hernández, Alvaro; Saavedra, Emma; Pardo, Juan P; Ralph, Stephen J; Rodríguez-Enríquez, Sara

    2014-05-01

    Applying basic biochemical principles, this review analyzes data that contrasts with the Warburg hypothesis that glycolysis is the exclusive ATP provider in cancer cells. Although disregarded for many years, there is increasing experimental evidence demonstrating that oxidative phosphorylation (OxPhos) makes a significant contribution to ATP supply in many cancer cell types and under a variety of conditions. Substrates oxidized by normal mitochondria such as amino acids and fatty acids are also avidly consumed by cancer cells. In this regard, the proposal that cancer cells metabolize glutamine for anabolic purposes without the need for a functional respiratory chain and OxPhos is analyzed considering thermodynamic and kinetic aspects for the reductive carboxylation of 2-oxoglutarate catalyzed by isocitrate dehydrogenase. In addition, metabolic control analysis (MCA) studies applied to energy metabolism of cancer cells are reevaluated. Regardless of the experimental/environmental conditions and the rate of lactate production, the flux-control of cancer glycolysis is robust in the sense that it involves the same steps: glucose transport, hexokinase, hexosephosphate isomerase and glycogen degradation, all at the beginning of the pathway; these steps together with phosphofructokinase 1 also control glycolysis in normal cells. The respiratory chain complexes exert significantly higher flux-control on OxPhos in cancer cells than in normal cells. Thus, determination of the contribution of each pathway to ATP supply and/or the flux-control distribution of both pathways in cancer cells is necessary in order to identify differences from normal cells which may lead to the design of rational alternative therapies that selectively target cancer energy metabolism. PMID:24513530

  12. Environmental oxygen tension regulates the energy metabolism and self-renewal of human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Catherine E Forristal

    Full Text Available Energy metabolism is intrinsic to cell viability but surprisingly has been little studied in human embryonic stem cells (hESCs. The current study aims to investigate the effect of environmental O2 tension on carbohydrate utilisation of hESCs. Highly pluripotent hESCs cultured at 5% O2 consumed significantly more glucose, less pyruvate and produced more lactate compared to those maintained at 20% O2. Moreover, hESCs cultured at atmospheric O2 levels expressed significantly less OCT4, SOX2 and NANOG than those maintained at 5% O2. To determine whether this difference in metabolism was a reflection of the pluripotent state, hESCs were cultured at 5% O2 in the absence of FGF2 for 16 hours leading to a significant reduction in the expression of SOX2. In addition, these cells consumed less glucose and produced significantly less lactate compared to those cultured in the presence of FGF2. hESCs maintained at 5% O2 were found to consume significantly less O2 than those cultured in the absence of FGF2, or at 20% O2. GLUT1 expression correlated with glucose consumption and using siRNA and chromatin immunoprecipitation was found to be directly regulated by hypoxia inducible factor (HIF-2α at 5% O2. In conclusion, highly pluripotent cells associated with hypoxic culture consume low levels of O2, high levels of glucose and produce large amounts of lactate, while at atmospheric conditions glucose consumption and lactate production are reduced and there is an increase in oxidative metabolism. These data suggest that environmental O2 regulates energy metabolism and is intrinsic to the self-renewal of hESCs.

  13. TEST RESULTS FOR FUEL CELL OPERATION ON ANAEROBIC DIGESTER GAS

    Science.gov (United States)

    EPA, in conjunction with ONSI Corp., embarked on a project to define, design, test, and assess a fuel cell energy recovery system for application at anaerobic digester waste water (sewage) treatment plants. Anaerobic digester gas (ADG) is produced at these plants during the proce...

  14. Anaerobic digestion: biodegradability and biogas production of model wastes

    OpenAIRE

    Lausund, Erlend

    2014-01-01

    Anaerobic digestion is a desirable treatment practice in terms of minimizing volume, treating of pollutants and biogas production. In this thesis model wastes have been investigated with respect to biogas and methane production in order to find out what wastes are suitable for anaerobic digestion, and discussing ways to further the research to optimize the production of renewable energy.

  15. Photosynthetic H2 metabolism in Chlamydomonas reinhardtii (unicellular green algae).

    Science.gov (United States)

    Melis, Anastasios

    2007-10-01

    Unicellular green algae have the ability to operate in two distinctly different environments (aerobic and anaerobic), and to photosynthetically generate molecular hydrogen (H2). A recently developed metabolic protocol in the green alga Chlamydomonas reinhardtii permitted separation of photosynthetic O2-evolution and carbon accumulation from anaerobic consumption of cellular metabolites and concomitant photosynthetic H2-evolution. The H2 evolution process was induced upon sulfate nutrient deprivation of the cells, which reversibly inhibits photosystem-II and O2-evolution in their chloroplast. In the absence of O2, and in order to generate ATP, green algae resorted to anaerobic photosynthetic metabolism, evolved H2 in the light and consumed endogenous substrate. This study summarizes recent advances on green algal hydrogen metabolism and discusses avenues of research for the further development of this method. Included is the mechanism of a substantial tenfold starch accumulation in the cells, observed promptly upon S-deprivation, and the regulated starch and protein catabolism during the subsequent H2-evolution. Also discussed is the function of a chloroplast envelope-localized sulfate permease, and the photosynthesis-respiration relationship in green algae as potential tools by which to stabilize and enhance H2 metabolism. In addition to potential practical applications of H2, approaches discussed in this work are beginning to address the biochemistry of anaerobic H2 photoproduction, its genes, proteins, regulation, and communication with other metabolic pathways in microalgae. Photosynthetic H2 production by green algae may hold the promise of generating a renewable fuel from nature's most plentiful resources, sunlight and water. The process potentially concerns global warming and the question of energy supply and demand. PMID:17721788

  16. Comparison between myocardial infarction and diabetes mellitus damage caused angiogenesis or energy metabolism.

    Science.gov (United States)

    Li, Chao; Lu, Chengzhi; Zhao, Xiangdong; Chen, Xin

    2015-01-01

    This study aims to compare and analyze lactate dehydrogenase (LDH), succinic dehydrogenase (SDH) and differences in capillary density level in the model of myocardial damage which caused by rats diabetes. The Wistar rats were divided into 4 groups, including control, diabetic, myocardial infarction and two diseases combined group. Ligate descending branch of left coronary artery on 1/3 position or inject streptozotocin into abdominal cavity to establish two kinds of disease models. After 6 w, obtain the myocardial tissues to do the vascular density analysis of tissue sections which are stained and cell tissue enzyme. Explore change of relevant index and differences among groups. Results indicated that degree of LDH and SDH decrease in two kinds of disease model. Compared with control group, level of myocardial vascular of myocardial injury group is higher, and diabetic group is higher than non diabetic group. Quantitative result of FFA in mitochondrial suspension of single disease group is higher than that of control group and two diseases combined group. Level of FFA and LDH of two diseases combined group is consistent with control group. In conclusion, after myocardial damage, which is caused by diabetes mellitus or myocardial infarction, degree of local vascularization increases, diabetes mellitus is more obvious. After myocardial damage, process of myocardial mitochondrial glycolysis and oxidative phosphorylation has some obstacles. But these two kinds of diseases all have cardiac muscle cell which can keep generated procedure of aerobic and anaerobic energy to instead the normal function of cardiac muscle. PMID:26885216

  17. Transcriptional regulation of the outer membrane porin gene ompW reveals its physiological role during the transition from the aerobic to the anaerobic lifestyle of Escherichia coli

    Directory of Open Access Journals (Sweden)

    Minfeng eXiao

    2016-05-01

    Full Text Available Understanding bacterial physiology relies on elucidating the regulatory mechanisms and cellular functions of those differentially expressed genes in response to environmental changes. A widespread Gram-negative bacterial outer membrane protein OmpW has been implicated in the adaptation to stresses in various species. It is recently found to be present in the regulon of the global anaerobic transcription factor FNR and ArcA in E. coli. However, little is known about the physiological implications of this regulatory disposition. In this study, we demonstrate that transcription of ompW is indeed mediated by a series of global regulators involved in the anaerobiosis of E. coli. We show that FNR can both activate and repress the expression of ompW through its direct binding to two distinctive sites, -81.5 and -126.5 bp respectively, on ompW promoter. ArcA also participates in repression of ompW under anaerobic condition, but in an FNR dependent manner. Additionally, ompW is also subject to the regulation by CRP and NarL which senses the availability and types of carbon sources and respiration electron acceptors in the environment respectively, implying a role of OmpW in the carbon and energy metabolism of E. coli during its anaerobic adaptation. Molecular docking reveals that OmpW can bind fumarate, an alternative electron acceptor in anaerobic respiration, with sufficient affinity. Moreover, supplement of fumarate or succinate which belongs to the C4-dicarboxylates family of metabolite, to E. coli culture rescues OmpW-mediated colicin S4 killing. Taken together, we propose that OmpW is involved in anaerobic carbon and energy metabolism to mediate the transition from aerobic to anaerobic lifestyle in E. coli.

  18. Semecarpus anacardium (Bhallataka Alters the Glucose Metabolism and Energy Production in Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Jaya Aseervatham

    2011-01-01

    Full Text Available Glucose produced by gluconeogenesis and glycogenolysis plays an important role in aggravating hyperglycemia in diabetes, and altered mitochondrial function is associated with impaired energy production. The present study focuses on the effect of Semecarpus anacardium on carbohydrate metabolism and energy production in diabetic rats. Diabetes was induced by the administration of Streptozotocin at a dose of 50 mg/kg.b.wt. Three days after the induction, Semecarpus anacardium at a dose of 300 mg/kg.b.wt was administered for 21 days. After the experimental duration, the activities of the enzymes involved in Glycolysis, TCA cycle, gluconeogenesis, and glycogen were assayed in the liver and kidney of the experimental animals. In addition, to the complexes the protein expression of AKT and PI3K were assayed. The levels of the enzymes involved in Glycolysis and TCA cycle increased, while that of gluconeogensis decreased. The activities of the mitochondrial complexes were also favorably modulated. The expressions of PI3K and AKT also increased in the skeletal muscle. These effects may be attributed to the hypoglycemic and the antioxidative activity of Semecarpus anacardium. The results of the study revealed that Semecarpus anacardium was able to restore the altered activities of the enzymes involved in carbohydrate metabolism and energy production.

  19. Cardiac energy metabolism and oxidative stress biomarkers in diabetic rat treated with resveratrol.

    Science.gov (United States)

    Carolo dos Santos, Klinsmann; Pereira Braga, Camila; Octavio Barbanera, Pedro; Seiva, Fábio Rodrigues Ferreira; Fernandes Junior, Ary; Fernandes, Ana Angélica Henrique

    2014-01-01

    Resveratrol (RSV), polyphenol from grape, was studied to evaluate its effects on calorimetric parameters, energy metabolism, and antioxidants in the myocardium of diabetic rats. The animals were randomly divided into four groups (n = 8): C (control group): normal rats; C-RSV: normal rats receiving RSV; DM: diabetic rats; and DM-RSV: diabetics rats receiving RSV. Type 1 diabetes mellitus was induced with administration of streptozotocin (STZ; 60 mg(-1) body weight, single dose, i.p.). After 48 hours of STZ administration, the animals received RSV (1.0 mg/kg/day) for gavage for 30 days. Food, water, and energy intake were higher in the DM group, while administration of RSV caused decreases (pdiabetic rats showed higher serum-free fatty acid, which was normalized with RSV. Oxygen consumption (VO2) and carbon dioxide production (VCO2) decreased (plactate dehydrogenase compared to the DM-RSV group. Myocardial protein carbonyl was increased in the DM group. RSV increased reduced glutathione in the cardiac tissue of diabetic animals. The glutathione reductase activity was higher in the DM-RSV group compared to the DM group. In conclusion, diabetes is accompanied by cardiac energy metabolism dysfunction and change in the biomarkers of oxidative stress. The cardioprotective effect may be mediated through RVS's ability to normalize free fatty acid oxidation, enhance utilization glucose, and control the biomarkers' level of oxidative stress under diabetic conditions. PMID:25050809

  20. Endothelial nitric oxide synthase (NOS) deficiency affects energy metabolism pattern in murine oxidative skeletal muscle.

    Science.gov (United States)

    Momken, Iman; Fortin, Dominique; Serrurier, Bernard; Bigard, Xavier; Ventura-Clapier, Renée; Veksler, Vladimir

    2002-01-01

    Oxidative capacity of muscles correlates with capillary density and with microcirculation, which in turn depend on various regulatory factors, including NO generated by endothelial nitric oxide synthase (eNOS). To determine the role of eNOS in patterns of regulation of energy metabolism in various muscles, we studied mitochondrial respiration in situ in saponin-permeabilized fibres as well as the energy metabolism enzyme profile in the cardiac, soleus (oxidative) and gastrocnemius (glycolytic) muscles isolated from mice lacking eNOS (eNOS(-/-)). In soleus muscle, the absence of eNOS induced a marked decrease in both basal mitochondrial respiration without ADP (-32%; P <0.05) and maximal respiration in the presence of ADP (-29%; P <0.05). Furthermore, the eNOS(-/-) soleus muscle showed a decrease in total creatine kinase (-29%; P <0.05), citrate synthase (-31%; P <0.01), adenylate kinase (-27%; P <0.05), glyceraldehyde-3-phosphate dehydrogenase (-43%; P <0.01) and pyruvate kinase (-26%; P <0.05) activities. The percentage of myosin heavy chains I (slow isoform) was significantly increased from 24.3+/-1.5% in control to 30.1+/-1.1% in eNOS(-/-) soleus muscle ( P <0.05) at the expense of a slight non-significant decrease in the three other (fast) isoforms. Besides, eNOS(-/-) soleus showed a 28% loss of weight. Interestingly, we did not find differences in any parameters in cardiac and gastrocnemius muscles compared with respective controls. These results show that eNOS knockout has an important effect on muscle oxidative capacity as well on the activities of energy metabolism enzymes in oxidative (soleus) muscle. The absence of such effects in cardiac and glycolytic (gastrocnemius) muscle suggests a specific role for eNOS-produced NO in oxidative skeletal muscle. PMID:12123418

  1. Dual regulation of energy metabolism by p53 in human cervix and breast cancer cells.

    Science.gov (United States)

    Hernández-Reséndiz, Ileana; Román-Rosales, Alejandra; García-Villa, Enríque; López-Macay, Ambar; Pineda, Erika; Saavedra, Emma; Gallardo-Pérez, Juan Carlos; Alvarez-Ríos, Elizabeth; Gariglio, Patricio; Moreno-Sánchez, Rafael; Rodríguez-Enríquez, Sara

    2015-12-01

    The role of p53 as modulator of OxPhos and glycolysis was analyzed in HeLa-L (cells containing negligible p53 protein levels) and HeLa-H (p53-overexpressing) human cervix cancer cells under normoxia and hypoxia. In normoxia, functional p53, mitochondrial enzyme contents, mitochondrial electrical potential (ΔΨm) and OxPhos flux increased in HeLa-H vs. HeLa-L cells; whereas their glycolytic enzyme contents and glycolysis flux were unchanged. OxPhos provided more than 70% of the cellular ATP and proliferation was abolished by anti-mitochondrial drugs in HeLa-H cells. In hypoxia, both cell proliferations were suppressed, but HeLa-H cells exhibited a significant decrease in OxPhos protein contents, ΔΨm and OxPhos flux. Although glycolytic function was also diminished vs. HeLa-L cells in hypoxia, glycolysis provided more than 60% of cellular ATP in HeLa-H cells. The energy metabolism phenotype of HeLa-H cells was reverted to that of HeLa-L cells by incubating with pifithrin-α, a p53-inhibitor. In normoxia, the energy metabolism phenotype of breast cancer MCF-7 cells was similar to that of HeLa-H cells, whereas p53shRNAMCF-7 cells resembled the HeLa-L cell phenotype. In hypoxia, autophagy proteins and lysosomes contents increased 2-5 times in HeLa-H cells suggesting mitophagy activation. These results indicated that under normoxia p53 up-regulated OxPhos without affecting glycolysis, whereas under hypoxia, p53 down-regulated both OxPhos (severely) and glycolysis (weakly). These p53 effects appeared mediated by the formation of p53-HIF-1α complexes. Therefore, p53 exerts a dual and contrasting regulatory role on cancer energy metabolism, depending on the O₂level.

  2. Gasto energético aeróbico y anaeróbico en un circuito con cargas a seis intensidades diferentes. (Aerobic and anaerobic energy expenditure during at circuit weight training through six different intensities.

    Directory of Open Access Journals (Sweden)

    Rocío Cupeiro Coto

    2011-07-01

    Full Text Available ResumenEl entrenamiento con cargas es una actividad anaeróbica glucolítica intensa y se ha comprobado que el error en las estimaciones del gasto energético en esta actividad varía entre un 13 y un 30%. El principal objetivo de este trabajo es describir la contribución anaeróbica de energía en un circuito con cargas. Doce hombres (20-26 años y diecisiete mujeres (18-29 años estudiantes de Ciencias de la Actividad Física y del Deporte realizaron un entrenamiento en circuito de cargas a 6 intensidades diferentes (entre el 30% y 80% de su 15RM. Durante la totalidad de los circuitos se registró el gasto energético aeróbico por calorimetría indirecta, la frecuencia cardiaca con pulsómetro Polar® y la concentración de lactato en sangre capilar para medir la contribución anaeróbica. El incremento que produjo la energía anaeróbica se situó entre el 5,1% y un máximo del 13,5%, lo que hace evidente que medir o no la contribución anaeróbica en el entrenamiento en circuito puede provocar un error medio del 9,65%. Existen diferencias significativas (PAbstractResistance training is an intense anaerobic glycolytic activity and has been shown that estimates of energy expenditure in this activity turn out into an error that varies between 13 and 30%. The main aim of this paper is to describe the anaerobic energy contribution in circuit weight training. Twelve men (20-26 years and seventeen women (18-29 years students in Science of Physical Activity and Sport performed circuit training at six different intensities (between 30% and 80% of 15RM. During all the circuits aerobic energy expenditure was registered by indirect calorimetry, heart rate with Polar® monitors and lactate concentration in capillary blood to measure the anaerobic contribution. The increased due to anaerobic energy was between 5,1% and a maximum of 13,5%, which clearly means that to measure or not the anaerobic contribution in circuit training can lead to an average

  3. EVALUATION OF A TWO-STAGE TREATMENT OF DOMESTIC SEWAGE WITH ANAEROBIC-AEROBIC MICROBIAL FILM

    OpenAIRE

    A.Mesdaghinia

    1986-01-01

    The objective of this research was to study the feasibility of a two stage continuous system employing anaerobic-aerobic microbial film for domestic wastewater treatment and the effect of iron on the behavior of sulfate reducing bacteria in anaerobic metabolism. A bench scale system with an anaerobic filter followed by aerobic fixed units used plastic media and was operated in up flow manner with hydraulic detention times of 6 hours, whereas the aerobic unit utilized diffused aeration. Raw do...

  4. Wet and Dry Anaerobic Digestion of Biowaste and of Co-substrates

    OpenAIRE

    Li, Chaoran

    2015-01-01

    Treatment of municipal solid waste by anaerobic digestion can solve the environmental problems caused by this organic solid waste and also supply biogas as renewable energy for a sustainable development. In this study the improvement of wet anaerobic digestion by addition of co-substrates and the effect of moisture on dry anaerobic digestion were investigated.

  5. Going beyond energy intensity to understand the energy metabolism of nations: The case of Argentina

    OpenAIRE

    Recalde, Marina; Ramos Martín, Jesús

    2012-01-01

    The link between energy consumption and economic growth has been widely studied in the economic literature. Understanding this relationship is important from both an environmental and a socio-economic point of view, as energy consumption is crucial to economic activity and human environmental impact. This relevance is even higher for developing countries, since energy consumption per unit of output varies through the phases of development, increasing from an agricultural stage to an industria...

  6. Effect of exercise intensity on the expression of UCP2 and energy metabolism in rat myocardium

    OpenAIRE

    Li, Xiao-Yan; Ke MENG; Zhang, Hong-Ming; Ji, Li-li; Zhang, Guo-ming; Jin, Qun; Chen, Ying-Jian

    2015-01-01

    Objective  To study the effect of different exercise intensity on the expression of uncoupling protein 2 (UCP2) in mitochondria of rat myocardium, and investigate the correlation and significance between energy metabolism and UCP2. Methods Forty five male Wistar rats were randomly divided into 3 groups (15 each): normal control (NC) group, endurance exercise (EnE) group and exhaustive exercise (ExE) group. Four weeks later, both the serum concentration of free fatty acid (FFA) and the content...

  7. Environmental oxygen tension regulates the energy metabolism and self-renewal of human embryonic stem cells

    OpenAIRE

    Forristal, Catherine E; David R. Christensen; Chinnery, Fay E.; Raffaella Petruzzelli; Parry, Kate L.; Tilman Sanchez-Elsner; Franchesca D. Houghton

    2013-01-01

    Energy metabolism is intrinsic to cell viability but surprisingly has been little studied in human embryonic stem cells (hESCs). The current study aims to investigate the effect of environmental O2 tension on carbohydrate utilisation of hESCs. Highly pluripotent hESCs cultured at 5% O2 consumed significantly more glucose, less pyruvate and produced more lactate compared to those maintained at 20% O2. Moreover, hESCs cultured at atmospheric O2 levels expressed significantly less OCT4, SOX2 and...

  8. Differential expression of microRNAs in mouse liver under aberrant energy metabolic status[S

    OpenAIRE

    Li, Shengjie; Chen, Xi; Zhang, Hongjie; Liang, Xiangying; Xiang, Yang; Yu, Chaohui; Zen, Ke; Li, Youming; Zhang, Chen-Yu

    2009-01-01

    Despite years of effort, exact pathogenesis of nonalcoholic fatty liver disease (NAFLD) remains obscure. To gain an insight into the regulatory roles of microRNAs (miRNAs) in aberrant energy metabolic status and pathogenesis of NAFLD, we analyzed the expression of miRNAs in livers of ob/ob mice, streptozotocin (STZ)-induced type 1 diabetic mice, and normal C57BL/6 mice by miRNA microarray. Compared with normal C57BL/6 mice, ob/ob mice showed upregulation of eight miRNAs and downregulation of ...

  9. Redistribution of whole-body energy metabolism by exercise. A positron emission tomography study

    International Nuclear Information System (INIS)

    Our aim was to evaluate changes in glucose metabolism of skeletal muscles and viscera induced by different workloads using 18F-2-fluoro-2-deoxyglucose ([18F]FDG) and three-dimensional positron emission tomography (3-D PET). Five male volunteers performed ergometer bicycle exercise for 40 min at 40% and 70% of the maximal O2 consumption (VO2max). [18]FDG was injected 10 min later following the exercise task. Whole-body 3-D PET was performed. Five other male volunteers were studied as a control to compare with the exercise group. The PET image data were analyzed using manually defined regions of interest to quantify the regional metabolic rate of glucose (rMRGlc). Group comparisons were made using analysis of variance, and significant differences (P18F]FDG-PET can be used as an index of organ energy metabolism for moderate exercise workloads (70% VO2max). The results of this investigation may contribute to sports medicine and rehabilitation science. (author)

  10. Regulation of neurotrophic factors and energy metabolism by antidepressants in astrocytes

    KAUST Repository

    Martin, Jean Luc

    2013-09-01

    There is growing evidence that astrocytes are involved in the neuropathology of major depression. In particular, decreases in glial cell density observed in the cerebral cortex of individuals with major depressive disorder are accompanied by a reduction of several astrocytic markers suggesting that astrocyte dysfunction may contribute to the pathophysiology of major depression. In rodents, glial loss in the prefrontal cortex is sufficient to induce depressive-like behaviors and antidepressant treatment prevents the stress-induced reduction of astrocyte number in the hippocampus. Collectively, these data support the existence of a link between astrocyte loss or dysfunction, depressive-like behavior and antidepressant treatment. Astrocytes are increasingly recognized to play important roles in neuronal development, neurotransmission, synaptic plasticity and maintenance of brain homeostasis. It is also well established that astrocytes provide trophic, structural, and metabolic support to neurons. In this article, we review evidence that antidepressants regulate energy metabolism and neurotrophic factor expression with particular emphasis on studies in astrocytes. These observations support a role for astrocytes as new targets for antidepressants. The contribution of changes in astrocyte glucose metabolism and neurotrophic factor expression to the therapeutic effects of antidepressants remains to be established. © 2013 Bentham Science Publishers.

  11. Determinants of brain cell metabolic phenotypes and energy substrate utilization unraveled with a modeling approach.

    Directory of Open Access Journals (Sweden)

    Aitana Neves

    Full Text Available Although all brain cells bear in principle a comparable potential in terms of energetics, in reality they exhibit different metabolic profiles. The specific biochemical characteristics explaining such disparities and their relative importance are largely unknown. Using a modeling approach, we show that modifying the kinetic parameters of pyruvate dehydrogenase and mitochondrial NADH shuttling within a realistic interval can yield a striking switch in lactate flux direction. In this context, cells having essentially an oxidative profile exhibit pronounced extracellular lactate uptake and consumption. However, they can be turned into cells with prominent aerobic glycolysis by selectively reducing the aforementioned parameters. In the case of primarily oxidative cells, we also examined the role of glycolysis and lactate transport in providing pyruvate to mitochondria in order to sustain oxidative phosphorylation. The results show that changes in lactate transport capacity and extracellular lactate concentration within the range described experimentally can sustain enhanced oxidative metabolism upon activation. Such a demonstration provides key elements to understand why certain brain cell types constitutively adopt a particular metabolic profile and how specific features can be altered under different physiological and pathological conditions in order to face evolving energy demands.

  12. Nuclear receptor/microRNA circuitry links muscle fiber type to energy metabolism.

    Science.gov (United States)

    Gan, Zhenji; Rumsey, John; Hazen, Bethany C; Lai, Ling; Leone, Teresa C; Vega, Rick B; Xie, Hui; Conley, Kevin E; Auwerx, Johan; Smith, Steven R; Olson, Eric N; Kralli, Anastasia; Kelly, Daniel P

    2013-06-01

    The mechanisms involved in the coordinate regulation of the metabolic and structural programs controlling muscle fitness and endurance are unknown. Recently, the nuclear receptor PPARβ/δ was shown to activate muscle endurance programs in transgenic mice. In contrast, muscle-specific transgenic overexpression of the related nuclear receptor, PPARα, results in reduced capacity for endurance exercise. We took advantage of the divergent actions of PPARβ/δ and PPARα to explore the downstream regulatory circuitry that orchestrates the programs linking muscle fiber type with energy metabolism. Our results indicate that, in addition to the well-established role in transcriptional control of muscle metabolic genes, PPARβ/δ and PPARα participate in programs that exert opposing actions upon the type I fiber program through a distinct muscle microRNA (miRNA) network, dependent on the actions of another nuclear receptor, estrogen-related receptor γ (ERRγ). Gain-of-function and loss-of-function strategies in mice, together with assessment of muscle biopsies from humans, demonstrated that type I muscle fiber proportion is increased via the stimulatory actions of ERRγ on the expression of miR-499 and miR-208b. This nuclear receptor/miRNA regulatory circuit shows promise for the identification of therapeutic targets aimed at maintaining muscle fitness in a variety of chronic disease states, such as obesity, skeletal myopathies, and heart failure.

  13. Bone and energy metabolism parameters in professional cyclists during the Giro d'Italia 3-weeks stage race.

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    Giovanni Lombardi

    Full Text Available Cycling is a not weight-bearing activity and is known to induce bone resorption. Stage races are really strenuous endurance performances affecting the energy homeostasis. The recently highlighted link, in the co-regulation of bone and energy metabolism, demonstrates a central role for the equilibrium between carboxylated and undercarboxylated forms of osteocalcin. Aim of this study was to understand the acute physiological responses to a cycling stage race in terms of bone turnover and energy metabolism and the possible co-regulative mechanisms underlying their relationship. We studied nine professional cyclists engaged in 2011 Giro d'Italia stage race. Pre-analytical and analytical phases tightly followed academic and anti-doping authority's recommendations. Bone and energy metabolism markers (bone alkaline phosphatase, tartrate-resistant acid phosphatase 5b, total and undercarboxylated osteocalcin, leptin and adiponectin and related hormones (cortisol and testosterone were measured, by Sandwich Enzyme Immunoassays, at days -1 (pre-race, 12 and 22 during the race. The power output and the energy expenditure (mean and accumulated were derived and correlated with the biochemical indexes. During the race, bone metabolism showed that an unbalance in behalf of resorption, which is enhanced, occurred along with a relative increase in the concentration of the undercarboxylated form of osteocalcin that was indirectly related to the enhanced energy expenditure, through adipokines modifications, with leptin decrease (high energy consumption and adiponectin increase (optimization of energy expenditure. The exertion due to heavy effort induced a decrease of cortisol, while testosterone levels resulted unchanged. In conclusion, during a 3-weeks stage race, bone metabolism is pushed towards resorption. A possible relationship between the bone and the energy metabolisms is suggested by the relative correlations among absolute and relative concentrations

  14. The Effect of Higher Sludge Recycling Rate on Anaerobic Treatment of Palm Oil Mill Effluent in a Semi-Commercial Closed Digester for Renewable Energy

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    Alawi Sulaiman

    2009-01-01

    Full Text Available Problem statement: A 500 m3 semi-commercial closed anaerobic digester was constructed for Palm Oil Mill Effluent (POME treatment and methane gas capture for renewable energy. During the start-up operation period, the Volatile Fatty Acids (VFA accumulation could not be controlled and caused instability on the system. Approach: A settling tank was installed and sludge was recycled as to provide a balanced microorganisms population for the treatment of POME and methane gas production. The effect of sludge recycling rate was studied by applying Organic Loading Rates (OLR (between 1.0 and 10.0 kgCOD m-3 day-1 at different sludge recycling rates (6, 12 and 18 m3 day-1. Results: At sludge recycling rate of 18 m3 day-1, the maximum OLR was 10.0 kgCOD m-3 day-1 with biogas and methane productivity of 1.5 and 0.9 m3 m-3 day-1, respectively. By increasing the sludge recycling rate the VFA concentration was controlled below its inhibitory limit (1000 mg L-1 and the COD removal efficiency recorded was above 95% which indicated good treatment performance for the digester. Two methanogens species (Methanosarcina sp. and Methanosaeta concilii had been identified from sludge samples obtained from the digester and recycled stream. Conclusion: By increasing the sludge recycling rate upon higher application of OLR, the treatment process was kept stable with high COD removal efficiency. The biogas and methane productivity were initially improved but reduced once OLR and recycling rate were increased to 10.0 kg COD m3 day-1 and 18 m3 day-1 respectively.

  15. Systems genetics analysis of body weight and energy metabolism traits in Drosophila melanogaster

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    Jordan Katherine W

    2010-05-01

    Full Text Available Abstract Background Obesity and phenotypic traits associated with this condition exhibit significant heritability in natural populations of most organisms. While a number of genes and genetic pathways have been implicated to play a role in obesity associated traits, the genetic architecture that underlies the natural variation in these traits is largely unknown. Here, we used 40 wild-derived inbred lines of Drosophila melanogaster to quantify genetic variation in body weight, the content of three major metabolites (glycogen, triacylglycerol, and glycerol associated with obesity, and metabolic rate in young flies. We chose these lines because they were previously screened for variation in whole-genome transcript abundance and in several adult life-history traits, including longevity, resistance to starvation stress, chill-coma recovery, mating behavior, and competitive fitness. This enabled us not only to identify candidate genes and transcriptional networks that might explain variation for energy metabolism traits, but also to investigate the genetic interrelationships among energy metabolism, behavioral, and life-history traits that have evolved in natural populations. Results We found significant genetically based variation in all traits. Using a genome-wide association screen for single feature polymorphisms and quantitative trait transcripts, we identified 337, 211, 237, 553, and 152 novel candidate genes associated with body weight, glycogen content, triacylglycerol storage, glycerol levels, and metabolic rate, respectively. Weighted gene co-expression analyses grouped transcripts associated with each trait in significant modules of co-expressed genes and we interpreted these modules in terms of their gene enrichment based on Gene Ontology analysis. Comparison of gene co-expression modules for traits in this study with previously determined modules for life-history traits identified significant modular pleiotropy between glycogen content

  16. Associations of fatty acids in cerebrospinal fluid with peripheral glucose concentrations and energy metabolism.

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    Reiner Jumpertz

    Full Text Available Rodent experiments have emphasized a role of central fatty acid (FA species, such as oleic acid, in regulating peripheral glucose and energy metabolism. Thus, we hypothesized that central FAs are related to peripheral glucose regulation and energy expenditure in humans. To test this we measured FA species profiles in cerebrospinal fluid (CSF and plasma of 32 individuals who stayed in our clinical inpatient unit for 6 days. Body composition was measured by dual energy X-ray absorptiometry and glucose regulation by an oral glucose test (OGTT followed by measurements of 24 hour (24EE and sleep energy expenditure (SLEEP as well as respiratory quotient (RQ in a respiratory chamber. CSF was obtained via lumbar punctures; FA concentrations were measured by liquid chromatography/mass spectrometry. As expected, FA concentrations were higher in plasma compared to CSF. Individuals with high concentrations of CSF very-long-chain saturated FAs had lower rates of SLEEP. In the plasma moderate associations of these FAs with higher 24EE were observed. Moreover, CSF monounsaturated long-chain FA (palmitoleic and oleic acid concentrations were associated with lower RQs and lower glucose area under the curve during the OGTT. Thus, FAs in the CSF strongly correlated with peripheral metabolic traits. These physiological parameters were most specific to long-chain monounsaturated (C16:1, C18:1 and very-long-chain saturated (C24:0, C26:0 FAs.Together with previous animal experiments these initial cross-sectional human data indicate that central FA species are linked to peripheral glucose and energy homeostasis.

  17. Isolation, identification and metabolic characterization of an anaerobic thermophilic bacterium%一嗜热厌氧杆菌的分离、鉴定及其代谢特征

    Institute of Scientific and Technical Information of China (English)

    兰贵红; 葛菊; 刘海昌; 唐全武; 张辉; 乔代容; 曹毅

    2012-01-01

    [Objective] To isolate, protect thermophilic microbial resources from petroleum reservoirs and analyze these main metabolic characterization. [Methods] The strain BF1 was isolated by Hungte anaerobic technique from Chenghai 1 Unit of Dagang oil field in China. Its taxonomic status determined by physiological, biochemical and 16S Rrna gene sequence analysis. Its effect of sulfur metabolism on the corrosion current was measured by electrochemical analysis. [Results] The strain BF1 was Gram-negative, strictly thermophilic anaerobic, top-sporulating, non-motile, rods, 0.42 μmx(l.6-5.4) μm, grew solitary, in pairs or in chains. Growth occurred at 45 °C-75 °C (optimum 60 °C), at Ph 4.5-8.5 (optimum 6.5). Specific growth rate (μm) was 0.99 h-1 and doubling time was 42 min. Substrates included glucose, melizitose, raffinose, mannose, lactose, fructose and ribose. The main products of glucose fermentation were CO2, H2, acetate and ethanol. The strain could reduce thiosulfate and sulfite to sulfide, and its tolerance limits were 75 mmol/L and 50 mmol/L, respectively. The electrochemical impedance reduced from 2 099 Ω/cm2 to 776 Ω/cm2 and the corrosion current increased from 9.936e-006 A to 3.25e-005 A after thiosulfate (50 mmol/L) was reduced. The fatty acids were mainly composed of saturated long chain fatty acids, with C15:0 the most, accounting for 70.6%. The G+C content of DNA was 34.0 mol%. The 16S Rrna gene sequence analysis indicated that the closest phylogenetic relatives were Thermoanaerobacter pseudethanolicus DSM2355T and T. Brockii subsp. Brockii DSM1457T, 98.3% and 98.0%, respectively. However, the strain BF1 was different with T. Pseudethanolicus DSM2355T and T. Brockii subsp. Brockii DSM1457T in doubling time, optimum temperature and substrates utilized, and different with T. Pseudethanolicus DSM 2355T in fatty acid profile. [Conclusion] The strain BF1 may be a new species of Thermoanaerobacter genus, the exact taxonomic status of it requires DNA

  18. Maternal melatonin programs the daily pattern of energy metabolism in adult offspring.

    Directory of Open Access Journals (Sweden)

    Danilo S Ferreira

    Full Text Available BACKGROUND: Shift work was recently described as a factor that increases the risk of Type 2 diabetes mellitus. In addition, rats born to mothers subjected to a phase shift throughout pregnancy are glucose intolerant. However, the mechanism by which a phase shift transmits metabolic information to the offspring has not been determined. Among several endocrine secretions, phase shifts in the light/dark cycle were described as altering the circadian profile of melatonin production by the pineal gland. The present study addresses the importance of maternal melatonin for the metabolic programming of the offspring. METHODOLOGY/PRINCIPAL FINDINGS: Female Wistar rats were submitted to SHAM surgery or pinealectomy (PINX. The PINX rats were divided into two groups and received either melatonin (PM or vehicle. The SHAM, the PINX vehicle and the PM females were housed with male Wistar rats. Rats were allowed to mate and after weaning, the male and female offspring were subjected to a glucose tolerance test (GTT, a pyruvate tolerance test (PTT and an insulin tolerance test (ITT. Pancreatic islets were isolated for insulin secretion, and insulin signaling was assessed in the liver and in the skeletal muscle by western blots. We found that male and female rats born to PINX mothers display glucose intolerance at the end of the light phase of the light/dark cycle, but not at the beginning. We further demonstrate that impaired glucose-stimulated insulin secretion and hepatic insulin resistance are mechanisms that may contribute to glucose intolerance in the offspring of PINX mothers. The metabolic programming described here occurs due to an absence of maternal melatonin because the offspring born to PINX mothers treated with melatonin were not glucose intolerant. CONCLUSIONS/SIGNIFICANCE: The present results support the novel concept that maternal melatonin is responsible for the programming of the daily pattern of energy metabolism in their offspring.

  19. On the origin of 3-methylglutaconic acid in disorders of mitochondrial energy metabolism.

    Science.gov (United States)

    Ikon, Nikita; Ryan, Robert O

    2016-09-01

    3-methylglutaconic acid (3MGA)-uria occurs in numerous inborn errors of metabolism (IEM) associated with compromised mitochondrial energy metabolism. This organic acid arises from thioester cleavage of 3-methylglutaconyl CoA (3MG CoA), an intermediate in leucine catabolism. In individuals harboring mutations in 3MG CoA hydratase (i.e., primary 3MGA-uria), dietary leucine is the source of 3MGA. In secondary 3MGA-uria, however, no leucine metabolism defects have been reported. While others have suggested 3MGA arises from aberrant isoprenoid shunting from cytosol to mitochondria, an alternative route posits that 3MG CoA arises in three steps from mitochondrial acetyl CoA. Support for this biosynthetic route in IEMs is seen by its regulated occurrence in microorganisms. The fungus, Ustilago maydis, the myxobacterium, Myxococcus xanthus and the marine cyanobacterium, Lyngbya majuscule, generate 3MG CoA (or acyl carrier protein derivative) in the biosynthesis of iron chelating siderophores, iso-odd chain fatty acids and polyketide/nonribosomal peptide products, respectively. The existence of this biosynthetic machinery in these organisms supports a model wherein, under conditions of mitochondrial dysfunction, accumulation of acetyl CoA in the inner mitochondrial space as a result of inefficient fuel utilization drives de novo synthesis of 3MG CoA. Since humans lack the downstream biosynthetic capability of the organisms mentioned above, as 3MG CoA levels rise, thioester hydrolysis yields 3MGA, which is excreted in urine as unspent fuel. Understanding the metabolic origins of 3MGA may increase its utility as a biomarker. PMID:27091556

  20. SUPPLY AND DEMAND IN CEREBRAL ENERGY METABOLISM: THE ROLE OF NUTRIENT TRANSPORTERS

    Science.gov (United States)

    Simpson, Ian A.; Carruthers, Anthony; Vannucci, Susan J.

    2007-01-01

    Glucose is the obligate energetic fuel for the mammalian brain and most studies of cerebral energy metabolism assume that the vast majority of cerebral glucose utilization fuels neuronal activity via oxidative metabolism, both in the basal and activated state. Glucose transporter proteins (GLUTs) deliver glucose from the circulation to the brain: GLUT1 in the microvascular endothelial cells of the blood brain barrier (BBB) and glia; GLUT3 in neurons. Lactate, the glycolytic product of glucose metabolism, is transported into and out of neural cells by the monocarboxylate transporters: MCT1 in the BBB and astrocytes and MCT2 in neurons. The proposal of the astrocyte-neuron lactate shuttle hypothesis (Pellerin and Magistretti, 1994) suggested that astrocytes play the primary role in cerebral glucose utilization and generate lactate for neuronal energetics, especially during activation. Since the identification of the GLUTs and MCTs in brain, much has been learned about their transport properties, i.e. capacity and affinity for substrate, which must be considered in any model of cerebral glucose uptake and utilization. Using concentrations and kinetic parameters of GLUT1 and GLUT3 in BBB endothelial cells, astrocytes and neurons, along with the corresponding kinetic properties of the monocarboxylate transporters, we have successfully modeled brain glucose and lactate levels as well as lactate transients in response to neuronal stimulation. Simulations based on these parameters suggest that glucose readily diffuses through the basal lamina and interstitium to neurons, which are primarily responsible for glucose uptake, metabolism, and the generation of the lactate transients observed upon neuronal activation. PMID:17579656