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Sample records for aerobic anoxygenic phototrophic

  1. Isolation and characterization of aerobic anoxygenic phototrophs from exposed soils from the Sør Rondane Mountains, East Antarctica.

    Science.gov (United States)

    Tahon, Guillaume; Willems, Anne

    2017-09-01

    This study investigated the culturable aerobic phototrophic bacteria present in soil samples collected in the proximity of the Belgian Princess Elisabeth Station in the Sør Rondane Mountains, East Antarctica. Until recently, only oxygenic phototrophic bacteria (Cyanobacteria) were well known from Antarctic soils. However, more recent non-cultivation-based studies have demonstrated the presence of anoxygenic phototrophs and, particularly, aerobic anoxygenic phototrophic bacteria in these areas. Approximately 1000 isolates obtained after prolonged incubation under different growth conditions were studied and characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Representative strains were identified by sequence analysis of 16S rRNA genes. More than half of the isolates grouped among known aerobic anoxygenic phototrophic taxa, particularly with Sphingomonadaceae, Methylobacterium and Brevundimonas. In addition, a total of 330 isolates were tested for the presence of key phototrophy genes. While rhodopsin genes were not detected, multiple isolates possessed key genes of the bacteriochlorophyll synthesis pathway. The majority of these potential aerobic anoxygenic phototrophic strains grouped with Alphaproteobacteria (Sphingomonas, Methylobacterium, Brevundimonas and Polymorphobacter). Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

  2. Distribution of aerobic anoxygenic phototrophs in the Eastern Adriatic Sea

    Czech Academy of Sciences Publication Activity Database

    Šantić, D.; Šestanović, S.; Vrdoljak, A.; Šolić, M.; Kušpilić, G.; Ninčević Gladan, Ž.; Koblížek, Michal

    2017-01-01

    Roč. 130, SEP 2017 (2017), s. 134-141 ISSN 0141-1136 R&D Projects: GA MŠk(CZ) LO1416 Institutional support: RVO:61388971 Keywords : Aerobic anoxygenic phototrophs * Adriatic sea * Picoplankton Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.101, year: 2016

  3. High turnover rates of aerobic anoxygenic phototrophs in European freshwater lakes

    Czech Academy of Sciences Publication Activity Database

    Cepáková, Zuzana; Hrouzek, Pavel; Žišková, Eva; Nuyanzina-Boldareva, Ekaterina; Šorf, M.; Kozlíková-Zapomělová, Eliška; Salka, I.; Grossart, H. P.; Koblížek, Michal

    2016-01-01

    Roč. 18, č. 12 (2016), s. 5063-5071 ISSN 1462-2912 R&D Projects: GA MŠk(CZ) LO1416; GA ČR GA13-11281S Institutional support: RVO:61388971 ; RVO:60077344 Keywords : Aerobic Anoxygenic Phototrophic bacteria * bacteriochlorophyll (BChl) * AAP bacteria Subject RIV: EE - Microbiology, Virology Impact factor: 5.395, year: 2016

  4. Leucine incorporation by aerobic anoxygenic phototrophic bacteria in the Delaware estuary

    OpenAIRE

    Stegman, Monica R; Cottrell, Matthew T; Kirchman, David L

    2014-01-01

    Aerobic anoxygenic phototrophic (AAP) bacteria are well known to be abundant in estuaries, coastal regions and in the open ocean, but little is known about their activity in any aquatic ecosystem. To explore the activity of AAP bacteria in the Delaware estuary and coastal waters, single-cell 3H-leucine incorporation by these bacteria was examined with a new approach that combines infrared epifluorescence microscopy and microautoradiography. The approach was used on samples from the Delaware c...

  5. Contribution of aerobic anoxygenic phototrophic bacteria to total organic carbon pool in aquatic system of subtropical karst catchments, Southwest China: evidence from hydrochemical and microbiological study.

    Science.gov (United States)

    Li, Qiang; Song, Ang; Peng, Wenjie; Jin, Zhenjiang; Müller, Werner E G; Wang, Xiaohong

    2017-06-01

    Aerobic anoxygenic phototrophic bacteria may play a particular role in carbon cycling of aquatic systems. However, little is known about the interaction between aerobic anoxygenic phototrophic bacteria and hydrochemistry in groundwater-surface water exchange systems of subtropical karst catchments. We carried out a detailed study on the abundance of aerobic anoxygenic phototrophic bacteria and bacterioplankton, hydrochemistry and taxonomy of bacterioplankton in the Maocun watershed, Southwest China, an area with karst geological background. Our results revealed that bacteria are the important contributors to total organic carbon source/sequestration in the groundwater-surface water of this area. The aerobic anoxygenic phototrophic bacteria, including β-Proteobacteria, also appear in the studied water system. In addition to that, the genus Polynucleobacter of the phototropic β-Proteobacteria shows a close link with those sampling sites by presenting bacterial origin organic carbon on CCA biplot and is found to be positively correlated with total nitrogen, dissolved oxygen and pH (r = 0.860, 0.747 and 0.813, respectively) in the Maocun watershed. The results suggest that Polynucleobacter might be involved in the production of organic carbon and might act as the negative feedback on global warming. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Evolutionary Divergence of Marine Aerobic Anoxygenic Phototrophic Bacteria as Seen from Diverse Organisations of Their Photosynthesis Gene Clusters

    Czech Academy of Sciences Publication Activity Database

    Zheng, Q.; Koblížek, Michal; Beatty, J.T.; Jiao, N.

    2013-01-01

    Roč. 66, č. 2013 (2013), s. 359-383 ISSN 0065-2296 R&D Projects: GA ČR GAP501/10/0221; GA MŠk ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : Aerobic anoxygenic phototrophic bacteria * photosynthesis * genome sequence Subject RIV: EE - Microbiology, Virology Impact factor: 1.740, year: 2013

  7. Carbon isotope fractionation by anoxygenic phototrophic bacteria in euxinic Lake Cadagno

    DEFF Research Database (Denmark)

    Posth, Nicole Rita Elisabeth; Bristow, L. A.; Cox, R. P.

    2017-01-01

    carbon (POC) in the Lake Cadagno chemocline. This large fractionation between the DIC and POC was also found in culture experiments carried out with anoxygenic phototrophic bacteria isolated from the lake. In the Lake Cadagno chemocline, anoxygenic phototrophic bacteria controlled the bulk C......Anoxygenic phototrophic bacteria utilize ancient metabolic pathways to link sulfur and iron metabolism to the reduction of CO2. In meromictic Lake Cadagno, Switzerland, both purple sulfur (PSB) and green sulfur anoxygenic phototrophic bacteria (GSB) dominate the chemocline community and drive...

  8. Carotenoid charge transfer states and their role in energy transfer processes in LH1-RC complexes from aerobic anoxygenic phototrophs

    Czech Academy of Sciences Publication Activity Database

    Šlouf, V.; Fuciman, M.; Dulebo, A.; Kaftan, D.; Koblížek, Michal; Frank, H.A.; Polívka, Tomáš

    2013-01-01

    Roč. 117, č. 38 (2013), s. 10987-10999 ISSN 1520-6106 R&D Projects: GA ČR(CZ) GAP205/11/1164; GA ČR GBP501/12/G055; GA MŠk(CZ) ED2.1.00/03.0110 Institutional research plan: CEZ:AV0Z50510513 Institutional support: RVO:61388971 ; RVO:60077344 Keywords : carotenoid * aerobic anoxygenic phototrophs * Roseobacter sp. Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.377, year: 2013

  9. Leucine incorporation by aerobic anoxygenic phototrophic bacteria in the Delaware estuary

    Science.gov (United States)

    Stegman, Monica R; Cottrell, Matthew T; Kirchman, David L

    2014-01-01

    Aerobic anoxygenic phototrophic (AAP) bacteria are well known to be abundant in estuaries, coastal regions and in the open ocean, but little is known about their activity in any aquatic ecosystem. To explore the activity of AAP bacteria in the Delaware estuary and coastal waters, single-cell 3H-leucine incorporation by these bacteria was examined with a new approach that combines infrared epifluorescence microscopy and microautoradiography. The approach was used on samples from the Delaware coast from August through December and on transects through the Delaware estuary in August and November 2011. The percent of active AAP bacteria was up to twofold higher than the percentage of active cells in the rest of the bacterial community in the estuary. Likewise, the silver grain area around active AAP bacteria in microautoradiography preparations was larger than the area around cells in the rest of the bacterial community, indicating higher rates of leucine consumption by AAP bacteria. The cell size of AAP bacteria was 50% bigger than the size of other bacteria, about the same difference on average as measured for activity. The abundance of AAP bacteria was negatively correlated and their activity positively correlated with light availability in the water column, although light did not affect 3H-leucine incorporation in light–dark experiments. Our results suggest that AAP bacteria are bigger and more active than other bacteria, and likely contribute more to organic carbon fluxes than indicated by their abundance. PMID:24824666

  10. Leucine incorporation by aerobic anoxygenic phototrophic bacteria in the Delaware estuary.

    Science.gov (United States)

    Stegman, Monica R; Cottrell, Matthew T; Kirchman, David L

    2014-11-01

    Aerobic anoxygenic phototrophic (AAP) bacteria are well known to be abundant in estuaries, coastal regions and in the open ocean, but little is known about their activity in any aquatic ecosystem. To explore the activity of AAP bacteria in the Delaware estuary and coastal waters, single-cell (3)H-leucine incorporation by these bacteria was examined with a new approach that combines infrared epifluorescence microscopy and microautoradiography. The approach was used on samples from the Delaware coast from August through December and on transects through the Delaware estuary in August and November 2011. The percent of active AAP bacteria was up to twofold higher than the percentage of active cells in the rest of the bacterial community in the estuary. Likewise, the silver grain area around active AAP bacteria in microautoradiography preparations was larger than the area around cells in the rest of the bacterial community, indicating higher rates of leucine consumption by AAP bacteria. The cell size of AAP bacteria was 50% bigger than the size of other bacteria, about the same difference on average as measured for activity. The abundance of AAP bacteria was negatively correlated and their activity positively correlated with light availability in the water column, although light did not affect (3)H-leucine incorporation in light-dark experiments. Our results suggest that AAP bacteria are bigger and more active than other bacteria, and likely contribute more to organic carbon fluxes than indicated by their abundance.

  11. Nitrogen transformation under different dissolved oxygen levels by the anoxygenic phototrophic bacterium Marichromatium gracile.

    Science.gov (United States)

    Hong, Xuan; Chen, Zhongwei; Zhao, Chungui; Yang, Suping

    2017-06-01

    Marichromatium gracile: YL28 (M. gracile YL28) is an anoxygenic phototrophic bacterial strain that utilizes ammonia, nitrate, or nitrite as its sole nitrogen source during growth. In this study, we investigated the removal and transformation of ammonium, nitrate, and nitrite by M. gracile YL28 grown in a combinatorial culture system of sodium acetate-ammonium, sodium acetate-nitrate and sodium acetate-nitrite in response to different initial dissolved oxygen (DO) levels. In the sodium acetate-ammonium system under aerobic conditions (initial DO = 7.20-7.25 mg/L), we detected a continuous accumulation of nitrate and nitrite. However, under semi-anaerobic conditions (initial DO = 4.08-4.26 mg/L), we observed a temporary accumulation of nitrate and nitrite. Interestingly, under anaerobic conditions (initial DO = 0.36-0.67 mg/L), there was little accumulation of nitrate and nitrite, but an increase in nitrous oxide production. In the sodium acetate-nitrite system, nitrite levels declined slightly under aerobic conditions, and nitrite was completely removed under semi-anaerobic and anaerobic conditions. In addition, M. gracile YL28 was able to grow using nitrite as the sole nitrogen source in situations when nitrogen gas produced by denitrification was eliminated. Taken together, the data indicate that M. gracile YL28 performs simultaneous heterotrophic nitrification and denitrification at low-DO levels and uses nitrite as the sole nitrogen source for growth. Our study is the first to demonstrate that anoxygenic phototrophic bacteria perform heterotrophic ammonia-oxidization and denitrification under anaerobic conditions.

  12. Ecology of aerobic anoxygenic phototrophic bacteria along an oligotrophic gradient in the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    D. Lamy

    2011-04-01

    Full Text Available Aerobic anoxygenic phototrophic (AAP bacteria are photoheterotrophic prokaryotes able to use both light and organic substrates for energy production. They are widely distributed in coastal and oceanic environments and may contribute significantly to the carbon cycle in the upper ocean. To better understand questions regarding links between the ecology of these photoheterotrophic bacteria and the trophic status of water masses, we examined their horizontal and vertical distribution and the effects of nutrient additions on their growth along an oligotrophic gradient in the Mediterranean Sea. Concentrations of bacteriochlorophyll-a (BChl-a and AAP bacterial abundance decreased from the western to the eastern basin of the Mediterranean Sea and were linked with concentrations of chlorophyll-a, nutrient and dissolved organic carbon. Inorganic nutrient and glucose additions to surface seawater samples along the oligotrophic gradient revealed that AAP bacteria were nitrogen- and carbon-limited in the ultraoligotrophic eastern basin. The intensity of the AAP bacterial growth response generally differed from that of the total bacterial growth response. BChl-a quota of AAP bacterial communities was significantly higher in the eastern basin than in the western basin, suggesting that reliance on phototrophy varied along the oligotrophic gradient and that nutrient and/or carbon limitation favors BChl-a synthesis.

  13. Diversity of cultivated and metabolically active aerobic anoxygenic phototrophic bacteria along an oligotrophic gradient in the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    C. Jeanthon

    2011-07-01

    Full Text Available Aerobic anoxygenic phototrophic (AAP bacteria play significant roles in the bacterioplankton productivity and biogeochemical cycles of the surface ocean. In this study, we applied both cultivation and mRNA-based molecular methods to explore the diversity of AAP bacteria along an oligotrophic gradient in the Mediterranean Sea in early summer 2008. Colony-forming units obtained on three different agar media were screened for the production of bacteriochlorophyll-a (BChl-a, the light-harvesting pigment of AAP bacteria. BChl-a-containing colonies represented a low part of the cultivable fraction. In total, 54 AAP strains were isolated and the phylogenetic analyses based on their 16S rRNA and pufM genes showed that they were all affiliated to the Alphaproteobacteria. The most frequently isolated strains belonged to Citromicrobium bathyomarinum, and Erythrobacter and Roseovarius species. Most other isolates were related to species not reported to produce BChl-a and/or may represent novel taxa. Direct extraction of RNA from seawater samples enabled the analysis of the expression of pufM, the gene coding for the M subunit of the reaction centre complex of aerobic anoxygenic photosynthesis. Clone libraries of pufM gene transcripts revealed that most phylotypes were highly similar to sequences previously recovered from the Mediterranean Sea and a large majority (~94 % was affiliated to the Gammaproteobacteria. The most abundantly detected phylotypes occurred in the western and eastern Mediterranean basins. However, some were exclusively detected in the eastern basin, reflecting the highest diversity of pufM transcripts observed in this ultra-oligotrophic region. To our knowledge, this is the first study to document extensively the diversity of AAP isolates and to unveil the active AAP community in an oligotrophic marine environment. By pointing out the discrepancies

  14. Genes essential for phototrophic growth by a purple alphaproteobacterium: Genes for phototrophic growth

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jianming [Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao Shandong Province People' s Republic of China; Department of Microbiology, University of Washington, Seattle WA USA; Yin, Liang [Department of Microbiology, University of Washington, Seattle WA USA; Lessner, Faith H. [Department of Biological Sciences, University of Arkansas, Fayetteville AR USA; Nakayasu, Ernesto S. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA USA; Payne, Samuel H. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA USA; Fixen, Kathryn R. [Department of Microbiology, University of Washington, Seattle WA USA; Gallagher, Larry [Department of Genome Sciences, University of Washington, Seattle WA USA; Harwood, Caroline S. [Department of Microbiology, University of Washington, Seattle WA USA

    2017-07-24

    Anoxygenic purple phototrophic bacteria have served as important models for studies of photophosphorylation. The pigment-protein complexes responsible for converting light energy to ATP are relatively simple and these bacteria can grow heterotrophically under aerobic conditions, thus allowing for the study of mutants defective in photophosphorylation. In the past, genes responsible for anoxygenic phototrophic growth have been identified in a number of different bacterial species. Here we systematically studied the genetic basis for this metabolism by using Tn-seq to identify genes essential for the anaerobic growth of the purple bacterium Rhodopseudomonas palustris on acetate in light. We identified 171 genes required for growth in this condition, 35 of which are annotated as photosynthesis genes. Among these are a few new genes not previously shown to be essential for phototrophic growth. We verified the essentiality of many of the genes we identified by analyzing the phenotypes of mutants we generated by Tn mutagenesis that had altered pigmentation. We used directed mutagenesis to verify that the R. palustris NADH:quinone oxidoreductase complex IE is essential for phototrophic growth. As a complement to the genetic data, we carried out proteomics experiments in which we found that 429 proteins were present in significantly higher amounts in cells grown anaerobically in light compared to aerobically. Among these were proteins encoded by subset of the phototrophic growth-essential genes.

  15. Competition for inorganic carbon between oxygenic and anoxygenic phototrophs in a hypersaline microbial mat, Guerrero Negro, Mexico

    DEFF Research Database (Denmark)

    Finke, Niko; Hoehler, Tori M.; Polerecky, Lubos

    2013-01-01

    While most oxygenic phototrophs harvest light only in the visible range (400-700 nm, VIS), anoxygenic phototrophs can harvest near infrared light (> 700 nm, NIR). To study interactions between the photosynthetic guilds we used microsensors to measure oxygen and gross oxygenic photosynthesis (gOP)...

  16. COMPETITION BETWEEN ANOXYGENIC PHOTOTROPHIC BACTERIA AND COLORLESS SULFUR BACTERIA IN A MICROBIAL MAT

    NARCIS (Netherlands)

    VISSCHER, PT; VANDENENDE, FP; SCHAUB, BEM; VANGEMERDEN, H

    The populations of chemolithoautotrophic (colorless) sulfur bacteria and anoxygenic phototrophic bacteria were enumerated in a marine microbial mat. The highest population densities were found in the 0-5 mm layer of the mat: 2.0 X 10(9) cells CM-3 sediment, and 4.0 X 10(7) cells cm-3 sediment for

  17. Picoplankton Bloom in Global South? A High Fraction of Aerobic Anoxygenic Phototrophic Bacteria in Metagenomes from a Coastal Bay (Arraial do Cabo--Brazil).

    Science.gov (United States)

    Cuadrat, Rafael R C; Ferrera, Isabel; Grossart, Hans-Peter; Dávila, Alberto M R

    2016-02-01

    Marine habitats harbor a great diversity of microorganism from the three domains of life, only a small fraction of which can be cultivated. Metagenomic approaches are increasingly popular for addressing microbial diversity without culture, serving as sensitive and relatively unbiased methods for identifying and cataloging the diversity of nucleic acid sequences derived from organisms in environmental samples. Aerobic anoxygenic phototrophic bacteria (AAP) play important roles in carbon and energy cycling in aquatic systems. In oceans, those bacteria are widely distributed; however, their abundance and importance are still poorly understood. The aim of this study was to estimate abundance and diversity of AAPs in metagenomes from an upwelling affected coastal bay in Arraial do Cabo, Brazil, using in silico screening for the anoxygenic photosynthesis core genes. Metagenomes from the Global Ocean Sample Expedition (GOS) were screened for comparative purposes. AAPs were highly abundant in the free-living bacterial fraction from Arraial do Cabo: 23.88% of total bacterial cells, compared with 15% in the GOS dataset. Of the ten most AAP abundant samples from GOS, eight were collected close to the Equator where solar irradiation is high year-round. We were able to assign most retrieved sequences to phylo-groups, with a particularly high abundance of Roseobacter in Arraial do Cabo samples. The high abundance of AAP in this tropical bay may be related to the upwelling phenomenon and subsequent picoplankton bloom. These results suggest a link between upwelling and light abundance and demonstrate AAP even in oligotrophic tropical and subtropical environments. Longitudinal studies in the Arraial do Cabo region are warranted to understand the dynamics of AAP at different locations and seasons, and the ecological role of these unique bacteria for biogeochemical and energy cycling in the ocean.

  18. Patterns in Abundance, Cell Size and Pigment Content of Aerobic Anoxygenic Phototrophic Bacteria along Environmental Gradients in Northern Lakes.

    Directory of Open Access Journals (Sweden)

    Lisa Fauteux

    Full Text Available There is now evidence that aerobic anoxygenic phototrophic (AAP bacteria are widespread across aquatic systems, yet the factors that determine their abundance and activity are still not well understood, particularly in freshwaters. Here we describe the patterns in AAP abundance, cell size and pigment content across wide environmental gradients in 43 temperate and boreal lakes of Québec. AAP bacterial abundance varied from 1.51 to 5.49 x 105 cells mL-1, representing <1 to 37% of total bacterial abundance. AAP bacteria were present year-round, including the ice-cover period, but their abundance relative to total bacterial abundance was significantly lower in winter than in summer (2.6% and 7.7%, respectively. AAP bacterial cells were on average two-fold larger than the average bacterial cell size, thus AAP cells made a greater relative contribution to biomass than to abundance. Bacteriochlorophyll a (BChla concentration varied widely across lakes, and was not related to AAP bacterial abundance, suggesting a large intrinsic variability in the cellular pigment content. Absolute and relative AAP bacterial abundance increased with dissolved organic carbon (DOC, whereas cell-specific BChla content was negatively related to chlorophyll a (Chla. As a result, both the contribution of AAP bacteria to total prokaryotic abundance, and the cell-specific BChla pigment content were positively correlated with the DOC:Chla ratio, both peaking in highly colored, low-chlorophyll lakes. Our results suggest that photoheterotrophy might represent a significant ecological advantage in highly colored, low-chlorophyll lakes, where DOC pool is chemically and structurally more complex.

  19. Diversity of pufM genes, involved in aerobic anoxygenic photosynthesis, in the bacterial communities associated with colonial ascidians.

    Science.gov (United States)

    Martínez-García, Manuel; Díaz-Valdés, Marta; Antón, Josefa

    2010-03-01

    Ascidians are invertebrate filter feeders widely distributed in benthic marine environments. A total of 14 different ascidian species were collected from the Western Mediterranean and their bacterial communities were analyzed by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene. Results showed that ascidian tissues harbored Bacteria belonging to Gamma- and Alphaproteobacteria classes, some of them phylogenetically related to known aerobic anoxygenic phototrophs (AAPs), such as Roseobacter sp. In addition, hierarchical cluster analysis of DGGE patterns showed a large variability in the bacterial diversity among the different ascidians analyzed, which indicates that they would harbor different bacterial communities. Furthermore, pufM genes, involved in aerobic anoxygenic photosynthesis in marine and freshwater systems, were widely detected within the ascidians analyzed, because nine out of 14 species had pufM genes inside their tissues. The pufM gene was only detected in those specimens that inhabited shallow waters (<77 m of depth). Most pufM gene sequences were very closely related to that of uncultured marine bacteria. Thus, our results suggest that the association of ascidians with bacteria related to AAPs could be a general phenomenon and that ascidian-associated microbiota could use the light that penetrates through the tunic tissue as an energy source.

  20. Computation studies into architecture and energy transfer properties of photosynthetic units from filamentous anoxygenic phototrophs

    Energy Technology Data Exchange (ETDEWEB)

    Linnanto, Juha Matti [Institute of Physics, University of Tartu, Riia 142, 51014 Tartu (Estonia); Freiberg, Arvi [Institute of Physics, University of Tartu, Riia 142, 51014 Tartu, Estonia and Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu (Estonia)

    2014-10-06

    We have used different computational methods to study structural architecture, and light-harvesting and energy transfer properties of the photosynthetic unit of filamentous anoxygenic phototrophs. Due to the huge number of atoms in the photosynthetic unit, a combination of atomistic and coarse methods was used for electronic structure calculations. The calculations reveal that the light energy absorbed by the peripheral chlorosome antenna complex transfers efficiently via the baseplate and the core B808–866 antenna complexes to the reaction center complex, in general agreement with the present understanding of this complex system.

  1. Novel acsF Gene Primers Revealed a Diverse Phototrophic Bacterial Population, Including Gemmatimonadetes, in Lake Taihu (China)

    Czech Academy of Sciences Publication Activity Database

    Huang, Y.; Zeng, Y.; Lu, H.; Feng, H.; Zeng, Yo.; Koblížek, Michal

    2016-01-01

    Roč. 82, č. 18 (2016), s. 5587-5594 ISSN 0099-2240 R&D Projects: GA ČR GA13-11281S; GA MŠk(CZ) LO1416 Institutional support: RVO:61388971 Keywords : AEROBIC ANOXYGENIC PHOTOTROPHS * MICROBIAL COMMUNITIES * OPERONS Subject RIV: EA - Cell Biology Impact factor: 3.807, year: 2016

  2. Bacterial anoxygenic photosynthesis on plant leaf surfaces.

    Science.gov (United States)

    Atamna-Ismaeel, Nof; Finkel, Omri; Glaser, Fabian; von Mering, Christian; Vorholt, Julia A; Koblížek, Michal; Belkin, Shimshon; Béjà, Oded

    2012-04-01

    The aerial surface of plants, the phyllosphere, is colonized by numerous bacteria displaying diverse metabolic properties that enable their survival in this specific habitat. Recently, we reported on the presence of microbial rhodopsin harbouring bacteria on the top of leaf surfaces. Here, we report on the presence of additional bacterial populations capable of harvesting light as a means of supplementing their metabolic requirements. An analysis of six phyllosphere metagenomes revealed the presence of a diverse community of anoxygenic phototrophic bacteria, including the previously reported methylobacteria, as well as other known and unknown phototrophs. The presence of anoxygenic phototrophic bacteria was also confirmed in situ by infrared epifluorescence microscopy. The microscopic enumeration correlated with estimates based on metagenomic analyses, confirming both the presence and high abundance of these microorganisms in the phyllosphere. Our data suggest that the phyllosphere contains a phylogenetically diverse assemblage of phototrophic species, including some yet undescribed bacterial clades that appear to be phyllosphere-unique. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  3. Distribution and Origin of Oxygen-Dependent and Oxygen-Independent Forms of Mg-Protoporphyrin Monomethylester Cyclase among Phototrophic Proteobacteria

    Czech Academy of Sciences Publication Activity Database

    Boldareva, Ekaterina; Bláhová, Zuzana; Sobotka, Roman; Koblížek, Michal

    2013-01-01

    Roč. 79, č. 8 (2013), s. 2596-2604 ISSN 0099-2240 R&D Projects: GA ČR GAP501/10/0221; GA ČR GBP501/12/G055; GA MŠk(CZ) ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : AEROBIC ANOXYGENIC PHOTOTROPHS * CHLOROPHYLL ISOCYCLIC RING * PURPLE BACTERIA Subject RIV: EE - Microbiology, Virology Impact factor: 3.952, year: 2013

  4. Sulfur metabolism in phototrophic sulfur bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Dahl, Christiane

    2008-01-01

    Phototrophic sulfur bacteria are characterized by oxidizing various inorganic sulfur compounds for use as electron donors in carbon dioxide fixation during anoxygenic photosynthetic growth. These bacteria are divided into the purple sulfur bacteria (PSB) and the green sulfur bacteria (GSB......). They utilize various combinations of sulfide, elemental sulfur, and thiosulfate and sometimes also ferrous iron and hydrogen as electron donors. This review focuses on the dissimilatory and assimilatory metabolism of inorganic sulfur compounds in these bacteria and also briefly discusses these metabolisms...... in other types of anoxygenic phototrophic bacteria. The biochemistry and genetics of sulfur compound oxidation in PSB and GSB are described in detail. A variety of enzymes catalyzing sulfur oxidation reactions have been isolated from GSB and PSB (especially Allochromatium vinosum, a representative...

  5. Phototrophic Fe(II-oxidation in the chemocline of a ferruginous meromictic lake

    Directory of Open Access Journals (Sweden)

    Xavier Alexis eWalter

    2014-12-01

    Full Text Available Precambrian Banded Iron Formation (BIF deposition was conventionally attributed to the precipitation of iron-oxides resulting from the abiotic reaction of ferrous iron (Fe(II with photosynthetically-produced oxygen. Earliest traces of oxygen date from 2.7 Ga, thus raising questions as to what may have caused BIF precipitation before oxygenic photosynthesis evolved. The discovery of anoxygenic phototrophic bacteria thriving through the oxidation of Fe(II has provided support for a biological origin for some BIFs, but despite reports suggesting that anoxygenic phototrophs may oxidize Fe(II in the environment, a model ecosystem of an ancient ocean where they are demonstrably active was lacking. Here we show that anoxygenic phototrophic bacteria contribute to Fe(II oxidation in the water column of the ferruginous sulfate-poor, meromictic lake La Cruz (Spain. We observed in-situ photoferrotrophic activity through stimulation of phototrophic carbon uptake in the presence of Fe(II, and determined light-dependent Fe(II-oxidation by the natural chemocline microbiota. Moreover, a photoferrotrophic bacterium most closely related to Chlorobium ferrooxidans was enriched from the ferruginous water column. Our study for the first time demonstrates a direct link between anoxygenic photoferrotrophy and the anoxic precipitation of Fe(III-oxides in a ferruginous water column, providing a plausible mechanism for the bacterial origin of BIF’s before the advent of free oxygen.

  6. Anoxic and oxic phototrophic primary production during the Precambrian

    DEFF Research Database (Denmark)

    Ebey-Honeycutt, Christina Marie; Bjerrum, Christian J.; Canfield, Donald Eugene

    2009-01-01

    of the mixed layer often lies above the base of the photic zone . Thus, an ecosystem model for the Precambrian should reflect the net primary production (NPP) of oxygenic phototrophs in the mixed layer and anoxygenic phototrophs below (NPPox and NPPred, respectively). Satelite data and a vertically generalized...

  7. Constraining the role of anoxygenic phototrophic Fe(II)-oxidizing bacteria in deposition of BIFs

    Science.gov (United States)

    Kappler, A.; Posth, N. R.; Hegler, F.; Wartha, E.; Huelin, S.

    2007-12-01

    Banded Iron Formations (BIFs) are Precambrian sedimentary deposits of alternating iron oxide and silica mineral layers. Their presence in the rock record ca.3.8-2.2 Ga makes them particularly intriguing formations for the debate over when oxygen became dominant on Earth. The mechanism(s) of BIF deposition is still unclear; suggestions including both abiotic and biotic processes. We are interested in constraining one of these proposed mechanisms; the direct biological oxidation of Fe(II) via anoxygenic Fe(II)-oxidizing autophototrophs. In order to find the limitations of photoferrotrophic BIF deposition, we take a holistic approach, investigating the oxidation of Fe(II) by modern Fe(II)-oxidizing phototrophs, the precipitation of Fe(III) (hydr)oxides, and the fate of the cell-mineral aggregates in the water column and at the basin floor. Specifically, physiology experiments with Fe(II)-oxidizing phototrophs under various conditions of light intensity, pH, Fe(II) concentration and temperature allow us to determine the environmental limits of such organisms. We carry out precipitation experiments to characterize the sedimentation rates, aggregate size and composition in order to resolve the effect of reactions in the water column. Finally, we simulate the diagenetic fate of these aggregates on the basin floor by placing them in gold capsules under T and P conditions relevant for the Transvaal Supergroup BIFs of South Africa. Recently, we have developed a tank simulating the Archean ocean in which the strains grow in continuous culture and collect the aggregates formed under various geochemical conditions. We aim to model the extent of and limitations to photoferrotrophs in BIF deposition. This information will help constrain whether biotic processes were dominant in the Archean ocean and will offer insight to the evolution of the early biogeosphere.

  8. Biofilm comprising phototrophic, diazotrophic, and hydrocarbon-utilizing bacteria: a promising consortium in the bioremediation of aquatic hydrocarbon pollutants.

    Science.gov (United States)

    Al-Bader, Dhia; Kansour, Mayada K; Rayan, Rehab; Radwan, Samir S

    2013-05-01

    Biofilms harboring simultaneously anoxygenic and oxygenic phototrophic bacteria, diazotrophic bacteria, and hydrocarbon-utilizing bacteria were established on glass slides suspended in pristine and oily seawater. Via denaturing gradient gel electrophoresis analysis on PCR-amplified rRNA gene sequence fragments from the extracted DNA from biofilms, followed by band amplification, biofilm composition was determined. The biofilms contained anoxygenic phototrophs belonging to alphaproteobacteria; pico- and filamentous cyanobacteria (oxygenic phototrophs); two species of the diazotroph Azospirillum; and two hydrocarbon-utilizing gammaproteobacterial genera, Cycloclasticus and Oleibacter. The coexistence of all these microbial taxa with different physiologies in the biofilm makes the whole community nutritionally self-sufficient and adequately aerated, a condition quite suitable for the microbial biodegradation of aquatic pollutant hydrocarbons.

  9. Distribution of aerobic anoxygenic phototrophic bacteria in glacial lakes of northern Europe

    Czech Academy of Sciences Publication Activity Database

    Mašín, Michal; Čuperová, Zuzana; Hojerová, Eva; Salka, I.; Grossart, H. P.; Koblížek, Michal

    2012-01-01

    Roč. 66, č. 1 (2012), s. 77-86 ISSN 0948-3055 R&D Projects: GA MŠk(CZ) ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : Aerobic photosynthetic bacteria * Lakes * Photoheterotrophy Subject RIV: EE - Microbiology, Virology Impact factor: 2.037, year: 2012

  10. Short Note Abundance of aerobic anoxygenic bacteria in freshwater lakes on James Ross Island, Antarctic Peninsula

    Czech Academy of Sciences Publication Activity Database

    Medová, Hana; Koblížek, Michal; Elster, Josef; Nedbalová, Linda

    2016-01-01

    Roč. 28, č. 2 (2016), s. 101-102 ISSN 0954-1020 R&D Projects: GA ČR GA15-00703S; GA MŠk ED2.1.00/03.0110 Institutional support: RVO:67985939 ; RVO:61388971 Keywords : aerobic anoxygenic bacteria * planktonic communities * bacteriochlorophyll Subject RIV: EE - Microbiology, Virology; EH - Ecology, Behaviour (BU-J) Impact factor: 1.461, year: 2016

  11. Aerobic Anoxygenic Photosynthesis Is Commonly Present within the Genus Limnohabitans.

    Science.gov (United States)

    Kasalický, Vojtěch; Zeng, Yonghui; Piwosz, Kasia; Šimek, Karel; Kratochvilová, Hana; Koblížek, Michal

    2018-01-01

    The genus Limnohabitans ( Comamonadaceae , Betaproteobacteria ) is a common and a highly active component of freshwater bacterioplanktonic communities. To date, the genus has been considered to contain only heterotrophic species. In this study, we detected the photosynthesis genes pufLM and bchY in 28 of 46 strains from three Limnohabitans lineages. The pufM sequences obtained are very closely related to environmental pufM sequences detected in various freshwater habitats, indicating the ubiquity and potential importance of photoheterotrophic Limnohabitans in nature. Additionally, we sequenced and analyzed the genomes of 5 potentially photoheterotrophic Limnohabitans strains, to gain further insights into their phototrophic capacity. The structure of the photosynthesis gene cluster turned out to be highly conserved within the genus Limnohabitans and also among all potentially photosynthetic Betaproteobacteria strains. The expression of photosynthetic complexes was detected in a culture of Limnohabitans planktonicus II-D5 T using spectroscopic and pigment analyses. This was further verified by a novel combination of infrared microscopy and fluorescent in situ hybridization. IMPORTANCE The data presented document that the capacity to perform anoxygenic photosynthesis is common among the members of the genus Limnohabitans , indicating that they may have a novel role in freshwater habitats. Copyright © 2017 American Society for Microbiology.

  12. Seeing green bacteria in a new light: genomics-enabled studies of the photosynthetic apparatus in green sulfur bacteria and filamentous anoxygenic phototrophic bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Bryant, Donald A

    2004-01-01

    Based upon their photosynthetic nature and the presence of a unique light-harvesting antenna structure, the chlorosome, the photosynthetic green bacteria are defined as a distinctive group in the Bacteria. However, members of the two taxa that comprise this group, the green sulfur bacteria...... (Chlorobi) and the filamentous anoxygenic phototrophic bacteria ("Chloroflexales"), are otherwise quite different, both physiologically and phylogenetically. This review summarizes how genome sequence information facilitated studies of the biosynthesis and function of the photosynthetic apparatus...... a and carotenoid biosynthesis enzymes, gene cluster analysis in Cfx. aurantiacus, and gene inactivation studies in Chl. tepidum. Based on these results, BChl a and BChl c biosynthesis is similar in the two organisms, whereas carotenoid biosynthesis differs significantly. In agreement with its facultative anaerobic...

  13. Evolution of the 3-hydroxypropionate bicycle and recent transfer of anoxygenic photosynthesis into the Chloroflexi

    Science.gov (United States)

    Shih, Patrick M.; Ward, Lewis M.; Fischer, Woodward W.

    2017-10-01

    Various lines of evidence from both comparative biology and the geologic record make it clear that the biochemical machinery for anoxygenic photosynthesis was present on early Earth and provided the evolutionary stock from which oxygenic photosynthesis evolved ca. 2.3 billion years ago. However, the taxonomic identity of these early anoxygenic phototrophs is uncertain, including whether or not they remain extant. Several phototrophic bacterial clades are thought to have evolved before oxygenic photosynthesis emerged, including the Chloroflexi, a phylum common across a wide range of modern environments. Although Chloroflexi have traditionally been thought to be an ancient phototrophic lineage, genomics has revealed a much greater metabolic diversity than previously appreciated. Here, using a combination of comparative genomics and molecular clock analyses, we show that phototrophic members of the Chloroflexi phylum are not particularly ancient, having evolved well after the rise of oxygen (ca. 867 million years ago), and thus cannot be progenitors of oxygenic photosynthesis. Similarly, results show that the carbon fixation pathway that defines this clade—the 3-hydroxypropionate bicycle—evolved late in Earth history as a result of a series of horizontal gene transfer events, explaining the lack of geological evidence for this pathway based on the carbon isotope record. These results demonstrate the role of horizontal gene transfer in the recent metabolic innovations expressed within this phylum, including its importance in the development of a novel carbon fixation pathway.

  14. Distribution of phototrophic populations and primary production in a microbial mat from the Ebro Delta, Spain.

    Science.gov (United States)

    Martínez-Alonso, Maira; Mir, Joan; Caumette, Pierre; Gaju, Núria; Guerrero, Ricardo; Esteve, Isabel

    2004-03-01

    Microbial mats arising in the sand flats of the Ebro Delta (Tarragona, Spain) were investigated during the summer season, when the community was highly developed. These mats are composed of three pigmented layers of phototrophic organisms, an upper brown layer mainly composed of Lyngbya aestuarii and diatoms, an intermediate green layer of the cyanobacterium Microcoleus chthonoplastes, and an underlying pink layer of a so-far unidentified purple sulfur bacterium. In the photic zone, oxygenic phototrophs constitute about 58% of total photosynthetic biomass, measured as biovolume, and anoxygenic phototrophs represent 42%. Diatoms constitute 11.8% of the oxygenic biomass, M. chthonoplastes 61.2%, and L. aestuarii and coccoid cyanobacteria 20.6 and 6.4%, respectively. In this laminated community, organic matter has an autochthonous origin, and photosynthesis is the most important source of organic carbon. Oxygen production reaches up to 27.2 mmol O(2) m(-2) h(-1), measured at 1000 microE m(-2) s(-1) light intensity, whereas oxidation of sulfide in the light has been calculated to be 18.6 mmol S m(-2) h(-1). This amount represents 26% of the total photosynthetic production in terms of photoassimilated carbon, demonstrating the important role of anoxygenic phototrophs as primary producers in the pink layer of Ebro Delta microbial mats.

  15. Astrobiological implications of dim light phototrophy in deep-sea red clays

    Science.gov (United States)

    Das, Anindita; Singh, Tanya; LokaBharathi, P. A.; Dhakephalkar, Prashant K.; Mallik, Sweta; Kshirsagar, Pranav R.; Khadge, N. H.; Nath, B. Nagender; Bhattacharya, Satadru; Dagar, Aditya Kumar; Kaur, Prabhjot; Ray, Dwijesh; Shukla, Anil D.; Fernandes, Christabelle E. G.; Fernandes, Sheryl O.; Thomas, Tresa Remya A.; Mamatha, S. S.; Mourya, Babu Shashikant; Meena, Ram Murti

    2017-02-01

    Red clays of Central Indian Basin (CIB) under influence of trace of Rodriguez Triple Junction exhibited chemoautotrophy, low temperature hydrothermal alterations and photoautotrophic potential. Seamount flank TVBC-08, hosting such signatures revealed dominance of aerobic anoxygenic phototroph Erythrobacter, with 93% of total 454 pyrosequencing tags. Subsequently, enrichments for both aerobic (Erythrobacter) and anaerobic anoxygenic phototrophs (green and purple sulphur bacteria) under red and white LED light illumination, with average irradiance 30.66 W m-2, were attempted for three red-clay sediment cores. Successful enrichments were obtained after incubation for c.a. 120 days at 4°± 2 °C and 25°± 2 °C, representing ambient psychrophilic and low temperature hydrothermal alteration conditions respectively. During hydrothermal cooling, a microbial succession from anaerobic chemolithotrophy to oxygenic photoautotrophy through anaerobic/aerobic anoxygenic phototrophic microbes is indicated. Spectral absorbance patterns of the methanol extracted cell pellets showed peaks corresponding to metal sulphide precipitations, the Soret band of chlorosome absorbance by photosystem II and absence of peaks at Qy transition band. Dendritic nano-structures of metal sulphides are common in these sediments and are comparable with other sulphidic paleo-marine Martian analogues. Significant blue and redshifts have been observed for the experimental samples relative to the un-inoculated medium. These observations indicate the propensity of metal-sulphide deposits contributing to chemiluminiscence supporting the growth of phototrophs at least partially, in the otherwise dark abyss. The effects of other geothermal heat and light sources are also under further consideration. The potential of phototrophic microbial cells to exhibit Doppler shift in absorbance patterns is significant towards understanding planetary microbial habitability. Planetary desiccation could considerably

  16. Ecology of aerobic anoxygenic phototrophs in aquatic environments

    Czech Academy of Sciences Publication Activity Database

    Koblížek, Michal

    2015-01-01

    Roč. 39, č. 6 (2015), s. 854-870 ISSN 0168-6445 R&D Projects: GA ČR GA13-11281S; GA MŠk LO1416 Institutional support: RVO:61388971 Keywords : photoheterotrophs * microbial loop * aquatic food webs Subject RIV: EE - Microbiology, Virology Impact factor: 13.687, year: 2015

  17. Geminicoccus roseus gen. nov., sp. nov., an aerobic phototrophic Alphaproteobacterium isolated from a marine aquaculture biofilter

    DEFF Research Database (Denmark)

    Foesel, Bärbel U.; Gößner, Anita S.; Drake, Harold L.

    2007-01-01

    A Gram-negative, strictly aerobic, diplococcoid bacterium (strain D2-3T) was isolated from the biofilter of a recirculating marine aquaculture system. Phylogenetic analysis of the 16S rRNA gene sequence of D2-3T indicated that the new organism occupied a novel lineage within the α-1 subclass...... of the DNA was 60.3±0.1 mol%. Phylogenetic, morphological, physiological, and biochemical analyses demonstrated that D2-3T represented a new aerobic phototrophic genus, for which the name Geminicoccus roseus gen. nov., sp. nov. is proposed for the type species (D2-3T=DSM 18922T=ATCC BAA-1445T)....

  18. Facultative anoxygenic photosynthesis in cyanobacteria driven by arsenite and sulfide with evidence for the support of nitrogen fixation

    Science.gov (United States)

    Wolfe-Simon, F.; Hoeft, S. E.; Baesman, S. M.; Oremland, R. S.

    2010-12-01

    The rise in atmospheric oxygen (O2) over geologic time is attributed to the evolution and widespread proliferation of oxygenic photosynthesis in cyanobacteria. However, cyanobacteria maintain a metabolic flexibility that may not always result in O2 release. In the environment, cyanobacteria may use a variety of alternative electron donors rather than water that are known to be used by other anoxygenic phototrophs (eg. purple sulfur bacteria) including reduced forms of sulfur, iron, nitrogen, and arsenic. Recent evidence suggests cyanobacteria actively take advantage of at least a few of these alternatives. We used a classical Winogradsky approach to enrich for cyanobacteria from the high salinity, elevated pH and arsenic-enriched waters of Mono Lake (CA). Experiments, optimized for cyanobacteria, revealed light-dependent, anaerobic arsenite-oxidation in sub-cultured sediment-free enrichments dominated by a filamentous cyanobacteria. We isolated and identified the dominant member of this enrichment to be a member of the Oscillatoriales by 16S rDNA. Addition of 1 mM arsenite induced facultative anoxygenic photosynthesis under continuous and circadian light. This isolate also oxidized sulfide under the same light-based conditions. Aerobic conditions elicited no arsenite oxidation in the light or dark and the isolate grew as a typical cyanobacterium using oxygenic photosynthesis. Under near-infrared light (700 nm) there was a direct correlation of enhanced growth with an increase in the rate arsenite or sulfide oxidation suggesting the use of photosystem I. Additionally, to test the wide-spread nature of this metabolism in the Oscillatoriales, we followed similar arsenite- and sulfide-driven facultative anoxygenic photosynthesis as well as nitrogen fixation (C2H2 reduction) in the axenic isolate Oscillatoria sp. CCMP 1731. Future characterization includes axenic isolation of the Mono Lake Oscillatoria sp. as well as the arsenite oxidase responsible for electron

  19. Seasonal changes of microbial communities in two shallow peat bog lakes

    Czech Academy of Sciences Publication Activity Database

    Lew, S.; Koblížek, Michal; Lew, M.; Medová, Hana; Glinska-Lewczuk, K.; Owsianny, P. M.

    2015-01-01

    Roč. 60, č. 2 (2015), s. 165-175 ISSN 0015-5632 R&D Projects: GA ČR GA13-11281S; GA MŠk ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : AEROBIC ANOXYGENIC PHOTOTROPHS * TARGETED OLIGONUCLEOTIDE PROBES * IN-SITU HYBRIDIZATION Subject RIV: EE - Microbiology, Virology Impact factor: 1.335, year: 2015

  20. Effects of grazing, phosphorus and light on the growth rates of major bacterioplankton taxa in the coastal NW Mediterranean

    Czech Academy of Sciences Publication Activity Database

    Sánchez, O.; Koblížek, Michal; Gasol, J.M.; Ferrera, I.

    2017-01-01

    Roč. 9, č. 3 (2017), s. 300-309 ISSN 1758-2229 R&D Projects: GA ČR GA13-11281S; GA MŠk(CZ) LO1416 Institutional support: RVO:61388971 Keywords : AEROBIC ANOXYGENIC PHOTOTROPHS * CATALYZED REPORTER DEPOSITION * NATURAL PLANKTONIC BACTERIA Subject RIV: EE - Microbiology , Virology OBOR OECD: Microbiology Impact factor: 3.363, year: 2016

  1. HiPIP oxido-reductase activity in membranes from aerobically grown cells of the facultative phototroph Rhodoferax fermentans

    DEFF Research Database (Denmark)

    Hochkoeppler, Alejandro; Kofod, Pauli; Zannoni, Davide

    1995-01-01

    The role of the periplasmically located, water-soluble, HiPIP (high-potential iron-sulfur protein) in the respiratory chain of the facultative phototroph Rhodoferax fermentans has been examined. The oxidized HiPIP is reduced by succinate-dependent respiration via the bc 1 complex, this reaction...... being inhibited by myxothiazol and/or stigmatellin. The reduced HiPIP can be oxidized by the membrane-bound cytochrome oxidase, this reaction being inhibited by 0.1 mM cyanide. We conclude that aerobically grown Rf. fermentans contains a redox chain in which HiPIP mediates electron transfer between...... the bc 1 complex and the cb-type cytochrome oxidase....

  2. Anoxygenic Photosynthesis Controls Oxygenic Photosynthesis in a Cyanobacterium from a Sulfidic Spring

    KAUST Repository

    Klatt, Judith M.; Alnajjar, Mohammad Ahmad; Yilmaz, Pelin; Lavik, Gaute; de Beer, Dirk; Polerecky, Lubos

    2015-01-01

    Before the Earth's complete oxygenation (0.58 to 0.55 billion years [Ga] ago), the photic zone of the Proterozoic oceans was probably redox stratified, with a slightly aerobic, nutrient-limited upper layer above a light-limited layer that tended toward euxinia. In such oceans, cyanobacteria capable of both oxygenic and sulfide-driven anoxygenic photosynthesis played a fundamental role in the global carbon, oxygen, and sulfur cycle. We have isolated a cyanobacterium, Pseudanabaena strain FS39, in which this versatility is still conserved, and we show that the transition between the two photosynthetic modes follows a surprisingly simple kinetic regulation controlled by this organism's affinity for H2S. Specifically, oxygenic photosynthesis is performed in addition to anoxygenic photosynthesis only when H2S becomes limiting and its concentration decreases below a threshold that increases predictably with the available ambient light. The carbon-based growth rates during oxygenic and anoxygenic photosynthesis were similar. However, Pseudanabaena FS39 additionally assimilated NO3 - during anoxygenic photosynthesis. Thus, the transition between anoxygenic and oxygenic photosynthesis was accompanied by a shift of the C/N ratio of the total bulk biomass. These mechanisms offer new insights into the way in which, despite nutrient limitation in the oxic photic zone in the mid-Proterozoic oceans, versatile cyanobacteria might have promoted oxygenic photosynthesis and total primary productivity, a key step that enabled the complete oxygenation of our planet and the subsequent diversification of life.

  3. Anoxygenic Photosynthesis Controls Oxygenic Photosynthesis in a Cyanobacterium from a Sulfidic Spring

    KAUST Repository

    Klatt, Judith M.

    2015-03-15

    Before the Earth\\'s complete oxygenation (0.58 to 0.55 billion years [Ga] ago), the photic zone of the Proterozoic oceans was probably redox stratified, with a slightly aerobic, nutrient-limited upper layer above a light-limited layer that tended toward euxinia. In such oceans, cyanobacteria capable of both oxygenic and sulfide-driven anoxygenic photosynthesis played a fundamental role in the global carbon, oxygen, and sulfur cycle. We have isolated a cyanobacterium, Pseudanabaena strain FS39, in which this versatility is still conserved, and we show that the transition between the two photosynthetic modes follows a surprisingly simple kinetic regulation controlled by this organism\\'s affinity for H2S. Specifically, oxygenic photosynthesis is performed in addition to anoxygenic photosynthesis only when H2S becomes limiting and its concentration decreases below a threshold that increases predictably with the available ambient light. The carbon-based growth rates during oxygenic and anoxygenic photosynthesis were similar. However, Pseudanabaena FS39 additionally assimilated NO3 - during anoxygenic photosynthesis. Thus, the transition between anoxygenic and oxygenic photosynthesis was accompanied by a shift of the C/N ratio of the total bulk biomass. These mechanisms offer new insights into the way in which, despite nutrient limitation in the oxic photic zone in the mid-Proterozoic oceans, versatile cyanobacteria might have promoted oxygenic photosynthesis and total primary productivity, a key step that enabled the complete oxygenation of our planet and the subsequent diversification of life.

  4. Anoxygenic photosynthesis controls oxygenic photosynthesis in a cyanobacterium from a sulfidic spring.

    Science.gov (United States)

    Klatt, Judith M; Al-Najjar, Mohammad A A; Yilmaz, Pelin; Lavik, Gaute; de Beer, Dirk; Polerecky, Lubos

    2015-03-01

    Before the Earth's complete oxygenation (0.58 to 0.55 billion years [Ga] ago), the photic zone of the Proterozoic oceans was probably redox stratified, with a slightly aerobic, nutrient-limited upper layer above a light-limited layer that tended toward euxinia. In such oceans, cyanobacteria capable of both oxygenic and sulfide-driven anoxygenic photosynthesis played a fundamental role in the global carbon, oxygen, and sulfur cycle. We have isolated a cyanobacterium, Pseudanabaena strain FS39, in which this versatility is still conserved, and we show that the transition between the two photosynthetic modes follows a surprisingly simple kinetic regulation controlled by this organism's affinity for H2S. Specifically, oxygenic photosynthesis is performed in addition to anoxygenic photosynthesis only when H2S becomes limiting and its concentration decreases below a threshold that increases predictably with the available ambient light. The carbon-based growth rates during oxygenic and anoxygenic photosynthesis were similar. However, Pseudanabaena FS39 additionally assimilated NO3 (-) during anoxygenic photosynthesis. Thus, the transition between anoxygenic and oxygenic photosynthesis was accompanied by a shift of the C/N ratio of the total bulk biomass. These mechanisms offer new insights into the way in which, despite nutrient limitation in the oxic photic zone in the mid-Proterozoic oceans, versatile cyanobacteria might have promoted oxygenic photosynthesis and total primary productivity, a key step that enabled the complete oxygenation of our planet and the subsequent diversification of life. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  5. Influence of Light on Carbon Utilization in Aerobic Anoxygenic Phototrophs

    Czech Academy of Sciences Publication Activity Database

    Hauruseu, Dzmitry; Koblížek, Michal

    2012-01-01

    Roč. 78, č. 20 (2012), s. 7414-7419 ISSN 0099-2240 R&D Projects: GA ČR GBP501/12/G055; GA MŠk(CZ) ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : ROSEOBACTER-DENITRIFICANS * PHOTOSYNTHETIC BACTERIUM * GENOME SEQUENCE Subject RIV: EE - Microbiology, Virology Impact factor: 3.678, year: 2012

  6. The variability of light-harvesting complexes in aerobic anoxygenic phototrophs

    Czech Academy of Sciences Publication Activity Database

    Selyanin, Vadim; Hauruseu, Dzmitry; Koblížek, Michal

    2016-01-01

    Roč. 128, č. 1 (2016), s. 35-43 ISSN 0166-8595 R&D Projects: GA ČR GBP501/12/G055; GA MŠk(CZ) LO1416 Institutional support: RVO:61388971 Keywords : Bacteriochlorophyll * Purple non-sulfur bacteria * Photosynthetic unit size Subject RIV: EE - Microbiology, Virology Impact factor: 3.864, year: 2016

  7. Novel acsF Gene Primers Revealed a Diverse Phototrophic Bacterial Population, Including Gemmatimonadetes, in Lake Taihu (China)

    DEFF Research Database (Denmark)

    Huang, Yili; Zeng, Yanhua; Lu, Hang

    2016-01-01

    Seq sequencing of the 16S rRNA, pufM, and bchY genes was carried out to assess the diversity of local phototrophic communities. In addition, we designed new degenerate primers of aerobic cyclase gene acsF, which serves as a convenient marker for both phototrophic Gemmatimonadetes and phototrophic Proteobacteria...... a diverse community of phototrophic Gemmatimonadetes forming 30 operational taxonomic units. These species represented 10.5 and 17.3% of the acsF reads in the upper semiaerobic sediment and anoxic sediment, whereas their abundance in the water column was ... fundamental biological processes on Earth. Recently, the presence of photosynthetic reaction centers has been reported from a rarely studied bacterial phylum, Gemmatimonadetes, but almost nothing is known about the diversity and environmental distribution of these organisms. The newly designed acsF primers...

  8. Distribution and Growth of Aerobic Anoxygenic Phototrophs in the Mediterranean Sea

    Czech Academy of Sciences Publication Activity Database

    Hojerová, Eva; Mašín, Michal; Brunet, C.; Ferrera, I.; Gasol, J.M.; Koblížek, Michal

    2011-01-01

    Roč. 13, č. 10 (2011), s. 2717-2725 ISSN 1462-2912 Institutional research plan: CEZ:AV0Z50200510 Keywords : BALTIC SEA * PHOTOHETEROTROPHIC BACTERIA * COMMUNITY STRUCTURE Subject RIV: EE - Microbiology, Virology Impact factor: 5.843, year: 2011

  9. Diverse Arrangement of Photosynthetic Gene Clusters in Aerobic Anoxygenic Phototrophic Bacteria

    Czech Academy of Sciences Publication Activity Database

    Zheng, Q.; Zhang, R.; Koblížek, Michal; Boldareva, Ekaterina; Yurkov, V.; Shi, Y.

    2011-01-01

    Roč. 6, č. 9 (2011), s. 1-7 E-ISSN 1932-6203 R&D Projects: GA ČR GAP501/10/0221 Institutional research plan: CEZ:AV0Z50200510 Keywords : RHODOBACTER-CAPSULATUS * CITROMICROBIUM-BATHYOMARINUM * REACTION CENTERS Subject RIV: EE - Microbiology, Virology Impact factor: 4.092, year: 2011

  10. Temporal Changes and Altitudinal Distribution of Aerobic Anoxygenic Phototrophs in Mountain Lakes

    Czech Academy of Sciences Publication Activity Database

    Čuperová, Zuzana; Holzer, E.; Salka, I.; Sommaruga, R.; Koblížek, Michal

    2013-01-01

    Roč. 79, č. 20 (2013), s. 6439-6446 ISSN 0099-2240 R&D Projects: GA MŠk MEB060911; GA ČR GA13-11281S; GA MŠk ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : FRESH-WATER BACTERIOPLANKTON * PHOTOHETEROTROPHIC BACTERIA * SURFACE WATERS Subject RIV: EE - Microbiology, Virology Impact factor: 3.952, year: 2013

  11. Low-Light Anoxygenic Photosynthesis and Fe-S-Biogeochemistry in a Microbial Mat.

    Science.gov (United States)

    Haas, Sebastian; de Beer, Dirk; Klatt, Judith M; Fink, Artur; Rench, Rebecca McCauley; Hamilton, Trinity L; Meyer, Volker; Kakuk, Brian; Macalady, Jennifer L

    2018-01-01

    We report extremely low-light-adapted anoxygenic photosynthesis in a thick microbial mat in Magical Blue Hole, Abaco Island, The Bahamas. Sulfur cycling was reduced by iron oxides and organic carbon limitation. The mat grows below the halocline/oxycline at 30 m depth on the walls of the flooded sinkhole. In situ irradiance at the mat surface on a sunny December day was between 0.021 and 0.084 μmol photons m -2 s -1 , and UV light (97% sequence identity) of clones affiliated with Prosthecochloris , a genus within the green sulfur bacteria (GSB), which are obligate anoxygenic phototrophs. Typical photopigments of brown-colored GSB, bacteriochlorophyll e and (β-)isorenieratene, were abundant in mat samples and their absorption properties are well-adapted to harvest light in the available green and possibly even UV-A spectra. Sulfide from the water column (3-6 μmol L -1 ) was the main source of sulfide to the mat as sulfate reduction rates in the mats were very low (undetectable-99.2 nmol cm -3 d -1 ). The anoxic water column was oligotrophic and low in dissolved organic carbon (175-228 μmol L -1 ). High concentrations of pyrite (FeS 2 ; 1-47 μmol cm -3 ) together with low microbial process rates (sulfate reduction, CO 2 fixation) indicate that the mats function as net sulfide sinks mainly by abiotic processes. We suggest that abundant Fe(III) (4.3-22.2 μmol cm -3 ) is the major source of oxidizing power in the mat, and that abiotic Fe-S-reactions play the main role in pyrite formation. Limitation of sulfate reduction by low organic carbon availability along with the presence of abundant sulfide-scavenging iron oxides considerably slowed down sulfur cycling in these mats.

  12. Biogeography of thermophilic phototrophic bacteria belonging to Roseiflexus genus.

    Science.gov (United States)

    Gaisin, Vasil A; Grouzdev, Denis S; Namsaraev, Zorigto B; Sukhacheva, Marina V; Gorlenko, Vladimir M; Kuznetsov, Boris B

    2016-03-01

    Isolated environments such as hot springs are particularly interesting for studying the microbial biogeography. These environments create an 'island effect' leading to genetic divergence. We studied the phylogeographic pattern of thermophilic anoxygenic phototrophic bacteria, belonging to the Roseiflexus genus. The main characteristic of the observed pattern was geographic and geochronologic fidelity to the hot springs within Circum-Pacific and Alpine-Himalayan-Indonesian orogenic belts. Mantel test revealed a correlation between genetic divergence and geographic distance among the phylotypes. Cluster analysis revealed a regional differentiation of the global phylogenetic pattern. The phylogeographic pattern is in correlation with geochronologic events during the break up of Pangaea that led to the modern configuration of continents. To our knowledge this is the first geochronological scenario of intercontinental prokaryotic taxon divergence. The existence of the modern phylogeographic pattern contradicts with the existence of the ancient evolutionary history of the Roseiflexus group proposed on the basis of its deep-branching phylogenetic position. These facts indicate that evolutionary rates in Roseiflexus varied over a wide range. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Ciliates as engineers of phototrophic biofilms

    NARCIS (Netherlands)

    Weerman, Ellen J.; van der Geest, Harm G.; van der Meulen, Myra D.; Manders, Erik M. M.; van de Koppel, Johan; Herman, Peter M. J.; Admiraal, Wim

    1. Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the 'engineering'

  14. Chemiosmotic Energy Conservation in Dinoroseobacter shibae: Proton Translocation Driven by Aerobic Respiration, Denitrification, and Photosynthetic Light Reaction

    Directory of Open Access Journals (Sweden)

    Christian Kirchhoff

    2018-05-01

    Full Text Available Dinoroseobacter shibae is an aerobic anoxygenic phototroph and able to utilize light energy to support its aerobic energy metabolism. Since the cells can also grow anaerobically with nitrate and nitrite as terminal electron acceptor, we were interested in how the cells profit from photosynthesis during denitrification and what the steps of chemiosmotic energy conservation are. Therefore, we conducted proton translocation experiments and compared O2-, NO3-, and NO2- respiration during different light regimes and in the dark. We used wild type cells and transposon mutants with knocked-out nitrate- and nitrite- reductase genes (napA and nirS, as well as a mutant (ppsR impaired in bacteriochlorophyll a synthesis. Light had a positive impact on proton translocation, independent of the type of terminal electron acceptor present. In the absence of an electron acceptor, however, light did not stimulate proton translocation. The light-driven add-on to proton translocation was about 1.4 H+/e- for O2 respiration and about 1.1 H+/e- for NO3- and NO2-. We could see that the chemiosmotic energy conservation during aerobic respiration involved proton translocation, mediated by the NADH dehydrogenase, the cytochrome bc1 complex, and the cytochrome c oxidase. During denitrification the last proton translocation step of the electron transport was missing, resulting in a lower H+/e- ratio during anoxia. Furthermore, we studied the type of light-harvesting and found that the cells were able to channel light from the green–blue spectrum most efficiently, while red light has only minor impact. This fits well with the depth profiles for D. shibae abundance in the ocean and the penetration depth of light with different wavelengths into the water column.

  15. Ciliates as engineers of phototrophic biofilms.

    NARCIS (Netherlands)

    Weerman, E.J.; van der Geest, H.G.; van der Meulen, M.D; Manders, E.M.M.; van de Koppel, J.; Herman, P.M.J.; Admiraal, W.

    2011-01-01

    1. Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the ‘engineering’

  16. Ciliates as engineers of phototrophic biofilms.

    NARCIS (Netherlands)

    Weerman, E.J.; Geest, H.G.; Meulen, M.D.; Manders, E.M.M.; Van de Koppel, J.; Herman, P.M.J.; Admiraal, W.

    2011-01-01

    1.Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the ‘engineering’ effects

  17. Biosynthesis of Chlorophyll a in a Purple Bacterial Phototroph and Assembly into a Plant Chlorophyll-Protein Complex.

    Science.gov (United States)

    Hitchcock, Andrew; Jackson, Philip J; Chidgey, Jack W; Dickman, Mark J; Hunter, C Neil; Canniffe, Daniel P

    2016-09-16

    Improvements to photosynthetic efficiency could be achieved by manipulating pigment biosynthetic pathways of photosynthetic organisms in order to increase the spectral coverage for light absorption. The development of organisms that can produce both bacteriochlorophylls and chlorophylls is one way to achieve this aim, and accordingly we have engineered the bacteriochlorophyll-utilizing anoxygenic phototroph Rhodobacter sphaeroides to make chlorophyll a. Bacteriochlorophyll and chlorophyll share a common biosynthetic pathway up to the precursor chlorophyllide. Deletion of genes responsible for the bacteriochlorophyll-specific modifications of chlorophyllide and replacement of the native bacteriochlorophyll synthase with a cyanobacterial chlorophyll synthase resulted in the production of chlorophyll a. This pigment could be assembled in vivo into the plant water-soluble chlorophyll protein, heterologously produced in Rhodobacter sphaeroides, which represents a proof-of-principle for the engineering of novel antenna complexes that enhance the spectral range of photosynthesis.

  18. Light enhances the growth rates of natural populations of aerobic anoxygenic phototrophic bacteria

    Czech Academy of Sciences Publication Activity Database

    Ferrera, I.; Sánchez, O.; Kolářová, Eva; Koblížek, Michal; Gasol, J.M.

    2017-01-01

    Roč. 11, č. 10 (2017), s. 2391-2393 ISSN 1751-7362 R&D Projects: GA ČR GA13-11281S; GA MŠk(CZ) LO1416 Institutional support: RVO:61388971 Keywords : MEDITERRANEAN-SEA * BACTERIOCHLOROPHYLL * REGIMEN Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 9.664, year: 2016

  19. Tellurite and Tellurate Reduction by the Aerobic Anoxygenic Phototroph Erythromonas ursincola, Strain KR99 Is Carried out by a Novel Membrane Associated Enzyme

    Directory of Open Access Journals (Sweden)

    Chris Maltman

    2017-04-01

    Full Text Available Erythromonas ursincola, strain KR99 isolated from a freshwater thermal spring of Kamchatka Island in Russia, resists and reduces very high levels of toxic tellurite under aerobic conditions. Reduction is carried out by a constitutively expressed membrane associated enzyme, which was purified and characterized. The tellurite reductase has a molecular weight of 117 kDa, and is comprised of two subunits (62 and 55 kDa in a 1:1 ratio. Optimal activity occurs at pH 7.0 and 28 °C. Tellurite reduction has a Vmax of 5.15 µmol/min/mg protein and a Km of 3.36 mM. The enzyme can also reduce tellurate with a Vmax and Km of 1.08 µmol/min/mg protein and 1.44 mM, respectively. This is the first purified membrane associated Te oxyanion reductase.

  20. Low-Light Anoxygenic Photosynthesis and Fe-S-Biogeochemistry in a Microbial Mat

    Directory of Open Access Journals (Sweden)

    Sebastian Haas

    2018-04-01

    Full Text Available We report extremely low-light-adapted anoxygenic photosynthesis in a thick microbial mat in Magical Blue Hole, Abaco Island, The Bahamas. Sulfur cycling was reduced by iron oxides and organic carbon limitation. The mat grows below the halocline/oxycline at 30 m depth on the walls of the flooded sinkhole. In situ irradiance at the mat surface on a sunny December day was between 0.021 and 0.084 μmol photons m-2 s-1, and UV light (<400 nm was the most abundant part of the spectrum followed by green wavelengths (475–530 nm. We measured a light-dependent carbon uptake rate of 14.5 nmol C cm-2 d-1. A 16S rRNA clone library of the green surface mat layer was dominated (74% by a cluster (>97% sequence identity of clones affiliated with Prosthecochloris, a genus within the green sulfur bacteria (GSB, which are obligate anoxygenic phototrophs. Typical photopigments of brown-colored GSB, bacteriochlorophyll e and (β-isorenieratene, were abundant in mat samples and their absorption properties are well-adapted to harvest light in the available green and possibly even UV-A spectra. Sulfide from the water column (3–6 μmol L-1 was the main source of sulfide to the mat as sulfate reduction rates in the mats were very low (undetectable-99.2 nmol cm-3 d-1. The anoxic water column was oligotrophic and low in dissolved organic carbon (175–228 μmol L-1. High concentrations of pyrite (FeS2; 1–47 μmol cm-3 together with low microbial process rates (sulfate reduction, CO2 fixation indicate that the mats function as net sulfide sinks mainly by abiotic processes. We suggest that abundant Fe(III (4.3–22.2 μmol cm-3 is the major source of oxidizing power in the mat, and that abiotic Fe-S-reactions play the main role in pyrite formation. Limitation of sulfate reduction by low organic carbon availability along with the presence of abundant sulfide-scavenging iron oxides considerably slowed down sulfur cycling in these mats.

  1. Distribution of free-living and particle-attached aerobic anoxygenic phototrophic bacteria in marine environments

    Czech Academy of Sciences Publication Activity Database

    Lami, R.; Čuperová, Zuzana; Ras, J.; Lebaron, P.; Koblížek, Michal

    2009-01-01

    Roč. 55, č. 1 (2009), s. 31-38 ISSN 0948-3055 R&D Projects: GA ČR GA206/07/0241; GA AV ČR 1QS500200570 Institutional research plan: CEZ:AV0Z50200510 Keywords : AAP bacteria * photoheterotrophy * free-living bacteria Subject RIV: EE - Microbiology, Virology Impact factor: 1.743, year: 2009

  2. Phototrophic biofilms and their potential applications

    NARCIS (Netherlands)

    Roeselers, G.; Van Loosdrecht, M.C.M.; Muyzer, G.

    2007-01-01

    Phototrophic biofilms occur on surfaces exposed to light in a range of terrestrial and aquatic environments. Oxygenic phototrophs like diatoms, green algae, and cyanobacteria are the major primary producers that generate energy and reduce carbon dioxide, providing the system with organic substrates

  3. Diversity of purple nonsulfur bacteria in shrimp ponds with varying mercury levels

    Directory of Open Access Journals (Sweden)

    Kanokwan Mukkata

    2016-07-01

    Full Text Available This research aimed to study the diversity of purple nonsulfur bacteria (PNSB and to investigate the effect of Hg concentrations in shrimp ponds on PNSB diversity. Amplification of the pufM gene was detected in 13 and 10 samples of water and sediment collected from 16 shrimp ponds in Southern Thailand. In addition to PNSB, other anoxygenic phototrophic bacteria (APB were also observed; purple sulfur bacteria (PSB and aerobic anoxygenic phototrophic bacteria (AAPB although most of them could not be identified. Among identified groups; AAPB, PSB and PNSB in the samples of water and sediment were 25.71, 11.43 and 8.57%; and 27.78, 11.11 and 22.22%, respectively. In both sample types, Roseobacter denitrificans (AAPB was the most dominant species followed by Halorhodospira halophila (PSB. In addition two genera, observed most frequently in the sediment samples were a group of PNSB (Rhodovulum kholense, Rhodospirillum centenum and Rhodobium marinum. The UPGMA dendrograms showed 7 and 6 clustered groups in the water and sediment samples, respectively. There was no relationship between the clustered groups and the total Hg (HgT concentrations in the water and sediment samples used (<0.002–0.03 μg/L and 35.40–391.60 μg/kg dry weight for studying the biodiversity. It can be concluded that there was no effect of the various Hg levels on the diversity of detected APB species; particularly the PNSB in the shrimp ponds.

  4. Size, density and composition of cell-mineral aggregates formed during anoxygenic phototrophic Fe(II) oxidation: Impact on modern and ancient environments

    DEFF Research Database (Denmark)

    Posth, Nicole R.; Huelin, Sonia; Konhauser, Kurt O.

    2010-01-01

    Cell-Fe(III) mineral aggregates produced by anoxygenic Fe(II)-oxidizing photoautotrophic microorganisms (photoferrotrophs) may be influential in the modern Fe cycle and were likely an integral part of ancient biogeochemical cycles on early Earth. While studies have focused on the environmental...... conditions under which modern photoferrotrophs grow and the kinetics, physiology and mechanism of Fe(II) oxidation, no systematic analyses of the physico-chemical characteristics of those aggregates, such as shape, size, density and chemical composition, have as yet been conducted. Herein, experimental...... results show most aggregates are bulbous or ragged in shape, with an average particle size of 10-40??m, and densities that typically range between 2.0 and 2.4g/cm 3; the cell fraction of the aggregates increased and their density decreased with initial Fe(II) concentration. The mineralogy of the ferric...

  5. Interactions among sulfide-oxidizing bacteria

    Science.gov (United States)

    Poplawski, R.

    1985-01-01

    The responses of different phototrophic bacteria in a competitive experimental system are studied, one in which primary factors such as H2S or light limited photometabolism. Two different types of bacteria shared one limited source of sulfide under specific conditions of light. The selection of a purple and a green sulfur bacteria and the cyanobacterium was based on their physiological similarity and also on the fact that they occur together in microbial mats. They all share anoxygenic photosynthesis, and are thus probably part of an evolutionary continuum of phototrophic organisms that runs from, strictly anaerobic physiology to the ability of some cyanobacteria to shift between anoxygenic bacterial style photosynthesis and the oxygenic kind typical of eukaryotes.

  6. 光合成の出現と進化

    OpenAIRE

    花田, 智; Satoshi, Hanada; 独立行政法人産業技術総合研究所(AIST)生物機能工学研究部門; Institute for Biological Resources and Functions National Institute of Advanced Industrial Science and Technology (AIST)

    2005-01-01

    Cyanobacteria can oxidize water using light energy, and which causes evolving oxygen molecules. In the history of life on the Earth, the origin of cyanobacteria is not so old, and anoxygenic photosynthesis has been established prior to the first appearance of oxygenic photosynthesis. Such phototrophs that photosynthesize without oxygen production still survive up to now and frequently found in various environments. Anoxygenic photosynthetic bacteria are taxonomically divided into four groups ...

  7. Model photoautrophs isolated from a Proterozoic ocean analog - aerobic life under anoxic conditions

    Science.gov (United States)

    Hamilton, T. L.; de Beer, D.; Klatt, J.; Macalady, J.; Weber, M.; Lott, C.; Chennu, A.

    2016-12-01

    The 1-2 billion year delay before the final rise of oxygen at the end of the Proterozoic represents an important gap in our understanding of ancient biogeochemical cycling. Primary production fueled by sulfide-dependent anoxygenic photosynthesis, including the activity of metabolically versatile cyanobacteria, has been invoked as a mechanism for sustaining low atmospheric O2 throughout much of the Proterozoic. However, we understand very little about photoautotrophs that inhabit Proterozoic-like environments present on Earth today. Here we report on the isolation and characterization of a cyanobacterium and a green sulfur bacterium that are the dominant members of pinnacle mats in Little Salt Spring—a karst sinkhole in Florida with perennially low levels of dissolved oxygen and sulfide. The red pinnacle mats bloom in the anoxic basin of the sinkhole and receive light that is of very poor quality to support photosynthesis. Characterization of the isolates is consistent with observations of oxygenic and anoxygenic photosynthesis in situ—both organisms perform anoxygenic photosynthesis under conditions of very low light quality and quantity. Oxygenic photosynthesis by the cyanobacterium isolate is inhibited by the presence of sulfide and under optimal light conditions, rates of anoxygenic photosynthesis are nearly double that of oxygenic photosynthesis. The green sulfur bacterium is tolerant of oxygen and has a very low affinity for sulfide. In Little Salt Spring, oxygenic photosynthesis occurs for only four hours a day and the water column remains anoxic because of a continuous supply of sulfide. Isolation and characterization of these photoautotrophs combined with our high resolution microsensor data in situ highlight microbial biogeochemical cycling in this exceptional site where aerobic microorganisms persist in a largely anoxic ecosystem.

  8. Insights into chemotaxonomic composition and carbon cycling of phototrophic communities in an artesian sulfur-rich spring (Zodletone, Oklahoma, USA), a possible analog for ancient microbial mat systems.

    Science.gov (United States)

    Bühring, S I; Sievert, S M; Jonkers, H M; Ertefai, T; Elshahed, M S; Krumholz, L R; Hinrichs, K-U

    2011-03-01

    Zodletone spring in Oklahoma is a unique environment with high concentrations of dissolved-sulfide (10 mm) and short-chain gaseous alkanes, exhibiting characteristics that are reminiscent of conditions that are thought to have existed in Earth's history, in particular the late Archean and early-to-mid Proterozoic. Here, we present a process-oriented investigation of the microbial community in two distinct mat formations at the spring source, (1) the top of the sediment in the source pool and (2) the purple streamers attached to the side walls. We applied a combination of pigment and lipid biomarker analyses, while functional activities were investigated in terms of oxygen production (microsensor analysis) and carbon utilization ((13)C incorporation experiments). Pigment analysis showed cyanobacterial pigments, in addition to pigments from purple sulfur bacteria (PSB), green sulfur bacteria (GSB) and Chloroflexus-like bacteria (CLB). Analysis of intact polar lipids (IPLs) in the source sediment confirmed the presence of phototrophic organisms via diacylglycerol phospholipids and betaine lipids, whereas glyceroldialkylglyceroltetraether additionally indicated the presence of archaea. No archaeal IPLs were found in the purple streamers, which were strongly dominated by betaine lipids. (13)C-bicarbonate- and -acetate-labeling experiments indicated cyanobacteria as predominant phototrophs in the source sediment, carbon was actively fixed by PSB/CLB/GSB in purple streamers by using near infrared light. Despite the presence of cyanobacteria, no oxygen could be detected in the presence of light, suggesting anoxygenic photosynthesis as the major metabolic process at this site. Our investigations furthermore indicated photoheterotrophy as an important process in both habitats. We obtained insights into a syntrophically operating phototrophic community in an ecosystem that bears resemblance to early Earth conditions, where cyanobacteria constitute an important contributor to

  9. Microenvironmental Ecology of Phototrophs from Extreme Environments

    DEFF Research Database (Denmark)

    Trampe, Erik

    In the three manuscripts presented in part one of this thesis, I analyse the physicochemical parameters, microenvironmental ecology and species composition of microbial phototrophs in ikaite tufa columns. This work was not easy, and encompassed underwater sampling and microsensor work demanding...... of the ikaite matrix, ii) measurements of diurnal fluctuations in irradiance and O2 under different light scenarios, and iii) the first in situ measurements of photosynthetic activity in the tufa columns (Manuscript 1). This was followed up with more detailed lab-based measurements close to the field site...... on spatial distribution of major taxonomic groups of phototrophs, detailed measurements of the optical properties of the ikaite matrix, in combination with various microscopic investigations of the phototrophic biofilms in the ikaite (Manuscript 2). Samples brought back for more advanced microscopy...

  10. Divergent mitochondrial respiratory chains in phototrophic relatives of apicomplexan parasites

    KAUST Repository

    Flegontov, Pavel

    2015-02-06

    Four respiratory complexes and ATP-synthase represent central functional units in mitochondria. In some mitochondria and derived anaerobic organelles, a few or all of these respiratory complexes have been lost during evolution. We show that the respiratory chain of Chromera velia, a phototrophic relative of parasitic apicomplexans, lacks complexes I and III, making it a uniquely reduced aerobic mitochondrion. In Chromera, putative lactate:cytochrome c oxidoreductases are predicted to transfer electrons from lactate to cytochrome c, rendering complex III unnecessary. The mitochondrial genome of Chromera has the smallest known protein-coding capacity of all mitochondria, encoding just cox1 and cox3 on heterogeneous linear molecules. In contrast, another photosynthetic relative of apicomplexans, Vitrella brassicaformis, retains the same set of genes as apicomplexans and dinoflagellates (cox1, cox3, and cob). © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  11. Divergent mitochondrial respiratory chains in phototrophic relatives of apicomplexan parasites

    KAUST Repository

    Flegontov, Pavel; Michá lek, Jan; Janouškovec, Jan; Lai, De Hua; Jirků, Milan; Hajdušková , Eva; Tomčala, Aleš; Otto, Thomas D.; Keeling, Patrick J.; Pain, Arnab; Oborní k, Miroslav; Lukeš, J.

    2015-01-01

    Four respiratory complexes and ATP-synthase represent central functional units in mitochondria. In some mitochondria and derived anaerobic organelles, a few or all of these respiratory complexes have been lost during evolution. We show that the respiratory chain of Chromera velia, a phototrophic relative of parasitic apicomplexans, lacks complexes I and III, making it a uniquely reduced aerobic mitochondrion. In Chromera, putative lactate:cytochrome c oxidoreductases are predicted to transfer electrons from lactate to cytochrome c, rendering complex III unnecessary. The mitochondrial genome of Chromera has the smallest known protein-coding capacity of all mitochondria, encoding just cox1 and cox3 on heterogeneous linear molecules. In contrast, another photosynthetic relative of apicomplexans, Vitrella brassicaformis, retains the same set of genes as apicomplexans and dinoflagellates (cox1, cox3, and cob). © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  12. Relationships between 16S-23S rRNA gene internal transcribed spacer DNA and genomic DNA similarities in the taxonomy of phototrophic bacteria

    International Nuclear Information System (INIS)

    Okamura, K; Hisada, T; Takata, K; Hiraishi, A

    2013-01-01

    Rapid and accurate identification of microbial species is essential task in microbiology and biotechnology. In prokaryotic systematics, genomic DNA-DNA hybridization is the ultimate tool to determine genetic relationships among bacterial strains at the species level. However, a practical problem in this assay is that the experimental procedure is laborious and time-consuming. In recent years, information on the 16S-23S rRNA gene internal transcribed spacer (ITS) region has been used to classify bacterial strains at the species and intraspecies levels. It is unclear how much information on the ITS region can reflect the genome that contain it. In this study, therefore, we evaluate the quantitative relationship between ITS DNA and entire genomic DNA similarities. For this, we determined ITS sequences of several species of anoxygenic phototrophic bacteria belonging to the order Rhizobiales, and compared with DNA-DNA relatedness among these species. There was a high correlation between the two genetic markers. Based on the regression analysis of this relationship, 70% DNA-DNA relatedness corresponded to 92% ITS sequence similarity. This suggests the usefulness of the ITS sequence similarity as a criterion for determining the genospecies of the phototrophic bacteria. To avoid the effects of polymorphism bias of ITS on similarities, PCR products from all loci of ITS were used directly as genetic probes for comparison. The results of ITS DNA-DNA hybridization coincided well with those of genomic DNA-DNA relatedness. These collective data indicate that the whole ITS DNA-DNA similarity can be used as an alternative to genomic DNA-DNA similarity.

  13. Transformation of monothioarsenate by haloalkaliphilic, anoxygenic photosynthetic purple sulfur bacteria.

    Science.gov (United States)

    Edwardson, Christian F; Planer-Friedrich, Britta; Hollibaugh, James T

    2014-12-01

    Thioarsenates are the dominant arsenic species in arsenic-rich, alkaline, and sulfidic waters, but bacterial interactions with these compounds have only recently been examined. Previous studies have shown that microorganisms play a role in the transformation of monothioarsenate to arsenate, including use of monothioarsenate as a chemolithotrophic electron donor coupled with oxygen as an electron acceptor. We obtained enrichment cultures from two saline, alkaline lakes (Mono Lake, CA and Big Soda Lake, NV) that are able to use monothioarsenate as the sole electron donor for anoxygenic photosynthesis. These anoxic cultures were able to convert a 1 mM mixture of thioarsenates completely to arsenate in c. 13 days and 4 mM monothioarsenate to arsenate in c. 17 days. This conversion was light dependent; thus, monothioarsenate can be used as the sole electron donor for anoxygenic photosynthesis. Both of the Mono Lake and Big Soda Lake enrichment cultures were dominated by an organism closely related to Ectothiorhodospira species. We tested additional strains of purple sulfur bacteria and found widespread ability to use monothioarsenate as an electron donor. The ability of bacteria to transform thioarsenates directly via anoxygenic photosynthesis adds a new perspective to the well-studied arsenic and sulfur cycles. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  14. Influence of selected environmental factors on the abundance of aerobic anoxygenic phototrophs in peat-bog lakes

    Czech Academy of Sciences Publication Activity Database

    Lew, S.; Lew, M.; Koblížek, Michal

    2016-01-01

    Roč. 23, č. 14 (2016), s. 13853-13863 ISSN 0944-1344 R&D Projects: GA ČR GA13-11281S Institutional support: RVO:61388971 Keywords : BACTERIAL COMMUNITY COMPOSITION * MEDITERRANEAN SEA * PHOTOHETEROTROPHIC BACTERIA Subject RIV: EH - Ecology, Behaviour Impact factor: 2.741, year: 2016

  15. Two-stage heterotrophic and phototrophic culture strategy for algal biomass and lipid production.

    Science.gov (United States)

    Zheng, Yubin; Chi, Zhanyou; Lucker, Ben; Chen, Shulin

    2012-01-01

    A two-stage heterotrophic and phototrophic culture strategy for algal biomass and lipid production was studied, wherein high density heterotrophic cultures of Chlorellasorokiniana serve as seed for subsequent phototrophic growth. The data showed growth rate, cell density and productivity of heterotrophic C.sorokiniana were 3.0, 3.3 and 7.4 times higher than phototrophic counterpart, respectively. Hetero- and phototrophic algal seeds had similar biomass/lipid production and fatty acid profile when inoculated into phototrophic culture system. To expand the application, food waste and wastewater were tested as feedstock for heterotrophic growth, and supported cell growth successfully. These results demonstrated the advantages of using heterotrophic algae cells as seeds for open algae culture system. Additionally, high inoculation rate of heterotrophic algal seed can be utilized as an effective method for contamination control. This two-stage heterotrophic phototrophic process is promising to provide a more efficient way for large scale production of algal biomass and biofuels. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Application of phototrophic biofilms: from fundamentals to processes.

    Science.gov (United States)

    Strieth, D; Ulber, R; Muffler, K

    2018-03-01

    Biotechnological production of valuables by microorganisms is commonly achieved by cultivating the cells as suspended solids in an appropriate liquid medium. However, the main portion of these organisms features a surface-attached growth in their native habitats. The utilization of such biofilms shows significant challenges, e.g. concerning control of pH, nutrient supply, and heat/mass transfer. But the use of biofilms might also enable novel and innovative production processes addressing robustness and strength of the applied biocatalyst, for example if variable conditions might occur in the process or a feedstock (substrate) is changed in its composition. Besides the robustness of a biofilm, the high density of the immobilized biocatalyst facilitates a simple separation of the catalyst and the extracellular product, whereas intracellular target compounds occur in a concentrated form; thus, expenses for downstream processing can be drastically reduced. While phototrophic organisms feature a fabulous spectrum of metabolites ranging from biofuels to biologically active compounds, the low cell density of phototrophic suspension cultures is still limiting their application for production processes. The review is focusing on pro- and eukaryotic microalgae featuring the production of valuable compounds and highlights requirements for their cultivation as phototrophic biofilms, i.e. setup as well as operation of biofilm reactors, and modeling of phototrophic growth.

  17. Genome Sequence of Rhodoferax antarcticus ANT.BRT; A Psychrophilic Purple Nonsulfur Bacterium from an Antarctic Microbial Mat

    Directory of Open Access Journals (Sweden)

    Jennifer M. Baker

    2017-02-01

    Full Text Available Rhodoferax antarcticus is an Antarctic purple nonsulfur bacterium and the only characterized anoxygenic phototroph that grows best below 20 °C. We present here a high-quality draft genome of Rfx. antarcticus strain ANT.BRT, isolated from an Antarctic microbial mat. The circular chromosome (3.8 Mbp of Rfx. antarcticus has a 59.1% guanine + cytosine (GC content and contains 4036 open reading frames. In addition, the bacterium contains a sizable plasmid (198.6 kbp, 48.4% GC with 226 open reading frames that comprises about 5% of the total genetic content. Surprisingly, genes encoding light-harvesting complexes 1 and 3 (LH1 and LH3, but not light-harvesting complex 2 (LH2, were identified in the photosynthesis gene cluster of the Rfx. antarcticus genome, a feature that is unique among purple phototrophs. Consistent with physiological studies that showed a strong capacity for nitrogen fixation in Rfx. antarcticus, a nitrogen fixation gene cluster encoding a molybdenum-type nitrogenase was present, but no alternative nitrogenases were identified despite the cold-active phenotype of this phototroph. Genes encoding two forms of ribulose 1,5-bisphosphate carboxylase/oxygenase were present in the Rfx. antarcticus genome, a feature that likely provides autotrophic flexibility under varying environmental conditions. Lastly, genes for assembly of both type IV pili and flagella are present, with the latter showing an unusual degree of clustering. This report represents the first genomic analysis of a psychrophilic anoxygenic phototroph and provides a glimpse of the genetic basis for maintaining a phototrophic lifestyle in a permanently cold, yet highly variable, environment.

  18. Microbial ecology of phototrophic biofilms

    NARCIS (Netherlands)

    Roeselers, G.

    2007-01-01

    Biofilms are layered structures of microbial cells and an extracellular matrix of polymeric substances, associated with surfaces and interfaces. Biofilms trap nutrients for growth of the enclosed microbial community and help prevent detachment of cells from surfaces in flowing systems. Phototrophic

  19. Phototrophic pigment production with microalgae

    NARCIS (Netherlands)

    Mulders, K.J.M.

    2014-01-01

    Abstract

    Microalgal pigments are regarded as natural alternatives for food colorants. To facilitate optimization of microalgae-based pigment production, this thesis aimed to obtain key insights in the pigment metabolism of phototrophic microalgae, with the main focus on secondary

  20. Long alkyl-chain imidazolium ionic liquids: Antibiofilm activity against phototrophic biofilms.

    Science.gov (United States)

    Reddy, G Kiran Kumar; Nancharaiah, Y V; Venugopalan, V P

    2017-07-01

    Biofilm formation is problematic and hence undesirable in medical and industrial settings. In addition to bacteria, phototrophic organisms are an integral component of biofilms that develop on surfaces immersed in natural waters. 1-Alkyl-3-methyl imidazolium ionic liquids (IL) with varying alkyl chain length were evaluated for their influence on the formation of monospecies (Navicula sp.) and multispecies biofilms under phototrophic conditions. An IL with a long alkyl side chain, 1-hexadecyl-3-methylimidaazolium chloride ([C 16 (MIM)][Cl]) retarded growth, adhesion and biofilm formation of Navicula sp. at concentrations as low as 5μM. Interestingly, [C 16 (MIM)][Cl] was very effective in preventing multispecies phototrophic biofilms on fibre reinforced plastic surfaces immersed in natural waters (fresh and seawater). SYTOX ® Green staining and chlorophyll leakage assay confirmed that the biocidal activity of the IL was exerted through cell membrane disruption. The data show that [C 16 (MIM)][Cl] is a potent inhibitor of phototrophic biofilms at micromolar concentrations and a promising agent for biofilm control in re-circulating cooling water systems. This is the first report that ionic liquids inhibit biofilm formation by phototrophic organisms which are important members of biofilms in streams and cooling towers. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Nonlinear effect of irradiance on photoheterotrophic activity and growth of the aerobic anoxygenic phototrophic bacterium Dinoroseobacter shibae

    Czech Academy of Sciences Publication Activity Database

    Piwosz, Kasia; Kaftan, David; Dean, Jason; Šetlík, Jiří; Koblížek, Michal

    2018-01-01

    Roč. 20, č. 2 (2018), s. 724-733 ISSN 1758-2229 R&D Projects: GA MŠk(CZ) LO1416 Institutional support: RVO:61388971 Keywords : PHOTOSYNTHETIC BACTERIUM * LEUCINE INCORPORATION * SOLAR-RADIATION Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.363, year: 2016

  2. Comparison of Growth Rates of Aerobic Anoxygenic Phototrophic Bacteria and Other Bacterioplankton Groups in Coastal Mediterranean Waters

    Czech Academy of Sciences Publication Activity Database

    Ferrera, I.; Gasol, J.M.; Sebastian, M.; Hojerová, Eva; Koblížek, Michal

    2011-01-01

    Roč. 77, č. 21 (2011), s. 7451-7458 ISSN 0099-2240 R&D Projects: GA ČR GAP501/10/0221 Institutional research plan: CEZ:AV0Z50200510 Keywords : CATALYZED REPORTER DEPOSITION * NATURAL AQUATIC SYSTEMS * IN-SITU HYBRIDIZATION Subject RIV: EE - Microbiology, Virology Impact factor: 3.829, year: 2011

  3. The Purification and Characterization of Superoxide Dismutase from Chloroflexus aurantiacus and the Effects of UV Radiation on the Activity of SOD and Catalase in Hydrothermal Mats of Yellowstone National Park

    Science.gov (United States)

    Lancaster, Vanessa; Blankenship, Robert E.; Rothschild, Lynn

    2001-01-01

    Chloroflexus aurantiacus is a thermotolerant anoxygenic green phototrophic bacterium that is prominent in alkaline hot springs at temperatures between 52 and 60 C. This species often grows in the hyperoxic environment beneath cyanobacterial mats at higher temperatures up to 70 - 72 C. Cf. aurantiacus is an evolutionarily important organism since it is in the earliest branch of the eubacteria that are capable of photosynthesis and many of its characteristics can be found in other diverse groups of phototrophic bacteria. Additional information is contained in the original extended abstract.

  4. Effect of salinity on diazotrophic activity and microbial composition of phototrophic communities from Bitter-1 soda lake (Kulunda Steppe, Russia).

    Science.gov (United States)

    Namsaraev, Zorigto; Samylina, Olga; Sukhacheva, Marina; Borisenko, Gennadii; Sorokin, Dimitry Y; Tourova, Tatiana

    2018-04-16

    Bitter-1 is a shallow hypersaline soda lake in Kulunda Steppe (Altai region, Russia). During a study period between 2005 and 2016, the salinity in the littoral area of the lake fluctuated within the range from 85 to 400 g/L (in July of each year). Light-dependent nitrogen fixation occurred in this lake up to the salt-saturating conditions. The rates increased with a decrease in salinity, both under environmental conditions and in laboratory simulations. The salinities below 100 g/L were favorable for light-dependent nitrogen fixation, while the process was dramatically inhibited above 200 g/L salts. The analysis of nifH genes in environmental samples and in enrichment cultures of diazotrophic phototrophs suggested that anaerobic fermenting and sulfate-reducing bacteria could participate in the dark nitrogen fixation process up to soda-saturating conditions. However, we cannot exclude the possibility that haloalkaliphilic nonheterocystous cyanobacteria (Euhalothece sp. and Geitlerinema sp.) and anoxygenic purple sulfur bacteria (Ectothiorhodospira sp.) might also play a role in the process at light conditions. The heterocystous cyanobacterium Nodularia sp. develops at low salinity (below 80 g/L) that is not characteristic for Bitter-1 Lake and thus does not make a significant contribution to the nitrogen fixation in this lake.

  5. Dynamics of anoxygenic photosynthesis in an experimental green sulphur bacteria biofilm

    DEFF Research Database (Denmark)

    Pringault, Olivier; Epping, E.H.G.; Guyoneaud, Remy

    1999-01-01

    procedure to solve the non-stationary general diffusion equation. A close agreement was found between the areal rates of anoxygenic photosynthesis during the cycling procedure and the steady state before the cycling experiment. For the different layers of the biofilm, the maximum activity was observed after...

  6. Cyanobacteria in sulfidic spring microbial mats can perform oxygenic and anoxygenic photosynthesis simultaneously during an entire diurnal period

    Directory of Open Access Journals (Sweden)

    Judith M Klatt

    2016-12-01

    Full Text Available We used microsensors to study the regulation of oxygenic and anoxygenic photosynthesis by light and sulfide in a cyanobacterium dominating microbial mats from cold sulfidic springs. Both photosynthetic modes were performed simultaneously over all H2S concentrations (1–2200 µM and irradiances (4–52 µmol photons m-2 s-1 tested. Anoxygenic photosynthesis increased with H2S concentration while the sum of oxygenic and anoxygenic photosynthetic rates was constant at each light intensity. Thus, the total photosynthetically driven electron transport rate was solely controlled by the irradiance level. The partitioning between the rates of these two photosynthetic modes was regulated by both light and H2S concentration. The plastoquinone pool (PQ receives electrons from sulfide:quinone:reductase (SQR in anoxygenic photosynthesis and from photosystem II (PSII in oxygenic photosynthesis. It is thus the link in the electron transport chain where both pathways intersect, and the compound that controls their partitioning. We fitted our data with a model of the photosynthetic electron transport that includes the kinetics of plastoquinone reduction and oxidation. The model results confirmed that the observed partitioning between photosynthetic modes can be explained by a simple kinetic control based on the affinity of SQR and PSII towards PQ. The SQR enzyme and PSII have similar affinities towards PQ, which explains the concurrent oxygenic and anoxygenic photosynthesis over an astonishingly wide range of H2S concentrations and irradiances. The elegant kinetic control of activity makes the cyanobacterium successful in the fluctuating spring environment. We discuss how these specific regulation mechanisms may have played a role in ancient H2S-rich oceans.

  7. Metagenomic evidence for the presence of phototrophic Gemmatimonadetes bacteria in diverse environments

    DEFF Research Database (Denmark)

    Zeng, Yonghui; Baumbach, Jan; Barbosa, Eudes Guilherme Vieira

    2016-01-01

    , biofilms, plant surfaces, intertidal sediment, soils, springs, and wastewater treatment plants, but none from marine waters or sediment. Phototrophic Gemmatimonadetes bacteria make up 0.4∼11.9% of whole phototrophic microbial communities in these habitats. Unexpectedly, an almost complete 37.9 kb long...... widely distributed in the environment and exhibit a higher genetic diversity than previously thought....

  8. Interactions between phototrophic bacteria in marine sediments

    NARCIS (Netherlands)

    de Wit, Rutger

    1989-01-01

    Phototrophic bacteria are the most consicious organisms occuring in laminated microbial sediment ecosystems (microbial mats). In the Waddensea area ecosystems consisting of a toplayer of the cyanobacterium Microleus chthonoplastes overlying a red layer of the purple sulfur bacterium Thiocapsa

  9. Regulation of electron transfer processes affects phototrophic mat structure and activity

    OpenAIRE

    Ha, Phuc T.; Renslow, Ryan S.; Atci, Erhan; Reardon, Patrick N.; Lindemann, Stephen R.; Fredrickson, James K.; Call, Douglas R.; Beyenal, Haluk

    2015-01-01

    Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located ne...

  10. Comparative Genomics of Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Ussery, David; Davenport, C; Tümmler, B

    2010-01-01

    Eleven completely sequenced Chlorobi genomes were compared in oligonucleotide usage, gene contents, and synteny. The green sulfur bacteria (GSB) are equipped with a core genome that sustains their anoxygenic phototrophic lifestyle by photosynthesis, sulfur oxidation, and CO(2) fixation. Whole...... weight of 10(6), and are probably instrumental for the bacteria to generate their own intimate (micro)environment....

  11. A dual-species co-cultivation system to study the interactions between Roseobacters and Dinoflagellates

    Directory of Open Access Journals (Sweden)

    Hui eWang

    2014-06-01

    Full Text Available Some microalgae in nature live in symbiosis with microorganisms that can enhance or inhibit growth, thus influencing the dynamics of phytoplankton blooms. In spite of the great ecological importance of these interactions, very few defined laboratory systems are available to study them in detail. Here we present a co-cultivation system consisting of the toxic phototrophic dinoflagellate Prorocentrum minimum and the photoheterotrophic alphaproteobacterium Dinoroseobacter shibae. In a mineral medium lacking a carbon source, vitamins for the bacterium and the essential vitamin B12 for the dinoflagellate, growth dynamics reproducibly went from a mutualistic phase, where both algae and bacteria grow, to a pathogenic phase, where the algae are killed by the bacteria. The data show a Jekyll and Hyde lifestyle that had been proposed but not previously demonstrated. We used RNAseq and microarray analysis to determine which genes of D. shibae are transcribed and differentially expressed in a light dependent way at an early time-point of the co-culture when the bacterium grows very slowly. Enrichment of bacterial mRNA for transcriptome analysis was optimized, but none of the available methods proved capable of removing dinoflagellate ribosomal RNA completely. RNAseq showed that a phasin encoding gene (phaP1 which is part of the polyhydroxyalkanoate (PHA metabolism operon represented approximately 10 % of all transcripts. Five genes for aerobic anoxygenic photosynthesis were down-regulated in the light, indicating that the photosynthesis apparatus was functional. A betaine-choline-carnitine-transporter (BCCT that may be used for dimethylsulfoniopropionate (DMSP uptake was the highest up-regulated gene in the light. The data suggest that at this early mutualistic phase of the symbiosis, PHA degradation might be the main carbon and energy source of D. shibae, supplemented in the light by degradation of DMSP and aerobic anoxygenic photosynthesis.

  12. Carbohydrate secretion by phototrophic communities in tidal sediments

    NARCIS (Netherlands)

    de Winder, B.; Staats, N.; Stal, L.J.; Paterson, D.M.

    1999-01-01

    Two different benthic phototrophic communities on tidal flats were investigated for their carbohydrate content and distribution. Carbohydrates were analysed as two operationally defined fractions, related to the difficulty of extraction from the sediment matrix. Water-soluble (colloidal) and EDTA-

  13. 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

  14. 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

  15. Air-dust-borne associations of phototrophic and hydrocarbon-utilizing microorganisms: promising consortia in volatile hydrocarbon bioremediation.

    Science.gov (United States)

    Al-Bader, Dhia; Eliyas, Mohamed; Rayan, Rihab; Radwan, Samir

    2012-11-01

    Aquatic and terrestrial associations of phototrophic and heterotrophic microorganisms active in hydrocarbon bioremediation have been described earlier. The question arises: do similar consortia also occur in the atmosphere? Dust samples at the height of 15 m were collected from Kuwait City air, and analyzed microbiologically for phototrophic and heterotrophic hydrocarbon-utilizing microorganisms, which were subsequently characterized according to their 16S rRNA gene sequences. The hydrocarbon utilization potential of the heterotrophs alone, and in association with the phototrophic partners, was measured quantitatively. The chlorophyte Gloeotila sp. and the two cyanobacteria Nostoc commune and Leptolyngbya thermalis were found associated with dust, and (for comparison) the cynobacteria Leptolyngbya sp. and Acaryochloris sp. were isolated from coastal water. All phototrophic cultures harbored oil vapor-utilizing bacteria in the magnitude of 10(5) g(-1). Each phototrophic culture had its unique oil-utilizing bacteria; however, the bacterial composition in Leptolyngbya cultures from air and water was similar. The hydrocarbon-utilizing bacteria were affiliated with Acinetobacter sp., Aeromonas caviae, Alcanivorax jadensis, Bacillus asahii, Bacillus pumilus, Marinobacter aquaeolei, Paenibacillus sp., and Stenotrophomonas maltophilia. The nonaxenic cultures, when used as inocula in batch cultures, attenuated crude oil in light and dark, and in the presence of antibiotics and absence of nitrogenous compounds. Aqueous and diethyl ether extracts from the phototrophic cultures enhanced the growth of the pertinent oil-utilizing bacteria in batch cultures, with oil vapor as a sole carbon source. It was concluded that the airborne microbial associations may be effective in bioremediating atmospheric hydrocarbon pollutants in situ. Like the aquatic and terrestrial habitats, the atmosphere contains dust-borne associations of phototrophic and heterotrophic hydrocarbon

  16. Hans Georg Trüper (1936–2016 and His Contributions to Halophile Research

    Directory of Open Access Journals (Sweden)

    Aharon Oren

    2016-05-01

    Full Text Available Prof. Hans Georg Trüper, one of the most important scientists in the field of halophile research, passed away on 9 March 2016 at the age of 79. I here present a brief obituary with special emphasis on Prof. Trüper’s contributions to our understanding of the halophilic prokaryotes and their adaptations to life in hypersaline environments. He has pioneered the study of the halophilic anoxygenic phototrophic sulfur bacteria of the Ectothiorhodospira—Halorhodospira group. Some of the species he and his group isolated from hypersaline and haloalkaline environments have become model organisms for the study of the mechanisms of haloadaptation: the functions of three major organic compounds – glycine betaine, ectoine, and trehalose – known to serve as “compatible solutes” in halophilic members of the Bacteria domain, were discovered during studies of these anoxygenic phototrophs. Prof. Trüper’s studies of hypersaline alkaline environments in Egypt also led to the isolation of the first known extremely halophilic archaeon (Natronomonas pharaonis. The guest editors dedicate this special volume of Life to the memory of Prof. Hans Georg Trüper.

  17. Light-Dependent Aerobic Methane Oxidation Reduces Methane Emissions from Seasonally Stratified Lakes

    Science.gov (United States)

    Oswald, Kirsten; Milucka, Jana; Brand, Andreas; Littmann, Sten; Wehrli, Bernhard; Kuypers, Marcel M. M.; Schubert, Carsten J.

    2015-01-01

    Lakes are a natural source of methane to the atmosphere and contribute significantly to total emissions compared to the oceans. Controls on methane emissions from lake surfaces, particularly biotic processes within anoxic hypolimnia, are only partially understood. Here we investigated biological methane oxidation in the water column of the seasonally stratified Lake Rotsee. A zone of methane oxidation extending from the oxic/anoxic interface into anoxic waters was identified by chemical profiling of oxygen, methane and δ13C of methane. Incubation experiments with 13C-methane yielded highest oxidation rates within the oxycline, and comparable rates were measured in anoxic waters. Despite predominantly anoxic conditions within the zone of methane oxidation, known groups of anaerobic methanotrophic archaea were conspicuously absent. Instead, aerobic gammaproteobacterial methanotrophs were identified as the active methane oxidizers. In addition, continuous oxidation and maximum rates always occurred under light conditions. These findings, along with the detection of chlorophyll a, suggest that aerobic methane oxidation is tightly coupled to light-dependent photosynthetic oxygen production both at the oxycline and in the anoxic bottom layer. It is likely that this interaction between oxygenic phototrophs and aerobic methanotrophs represents a widespread mechanism by which methane is oxidized in lake water, thus diminishing its release into the atmosphere. PMID:26193458

  18. Metabolomic profiling of the purple sulfur bacterium Allochromatium vinosum during growth on different reduced sulfur compounds and malate

    OpenAIRE

    Weissgerber, Thomas; Watanabe, Mutsumi; Hoefgen, Rainer; Dahl, Christiane

    2014-01-01

    Environmental fluctuations require rapid adjustment of the physiology of bacteria. Anoxygenic phototrophic purple sulfur bacteria, like Allochromatium vinosum, thrive in environments that are characterized by steep gradients of important nutrients for these organisms, i.e., reduced sulfur compounds, light, oxygen and carbon sources. Changing conditions necessitate changes on every level of the underlying cellular and molecular network. Thus far, two global analyses of A. vinosum responses to ...

  19. Insights into heliobacterial photosynthesis and physiology from the genome of Heliobacterium modesticaldum.

    Science.gov (United States)

    Sattley, W Matthew; Blankenship, Robert E

    2010-06-01

    The complete annotated genome sequence of Heliobacterium modesticaldum strain Ice1 provides our first glimpse into the genetic potential of the Heliobacteriaceae, a unique family of anoxygenic phototrophic bacteria. H. modesticaldum str. Ice1 is the first completely sequenced phototrophic representative of the Firmicutes, and heliobacteria are the only phototrophic members of this large bacterial phylum. The H. modesticaldum genome consists of a single 3.1-Mb circular chromosome with no plasmids. Of special interest are genomic features that lend insight to the physiology and ecology of heliobacteria, including the genetic inventory of the photosynthesis gene cluster. Genes involved in transport, photosynthesis, and central intermediary metabolism are described and catalogued. The obligately heterotrophic metabolism of heliobacteria is a key feature of the physiology and evolution of these phototrophs. The conspicuous absence of recognizable genes encoding the enzyme ATP-citrate lyase prevents autotrophic growth via the reverse citric acid cycle in heliobacteria, thus being a distinguishing differential characteristic between heliobacteria and green sulfur bacteria. The identities of electron carriers that enable energy conservation by cyclic light-driven electron transfer remain in question.

  20. Bioenergetics of photoheterotrophic bacteria in the oceans.

    Science.gov (United States)

    Kirchman, David L; Hanson, Thomas E

    2013-04-01

    Photoheterotrophic microbes, such as proteorhodopsin (PR)-based phototrophic (PRP) and aerobic anoxygenic phototrophic (AAP) bacteria, are well known to be abundant in the oceans, potentially playing unique roles in biogeochemical cycles. However, the contribution of phototrophy to the energy requirements of these bacteria has not been quantitatively examined to date. To better understand the implications of photoheterophy in the oceans, we calculated energy benefits and costs of phototrophy and compared net benefits with maintenance costs. Benefits depend on the number of photosynthetic units (PSUs), absorption cross-section area of each PSU as function of wavelength, the in situ light quality, and the energy yield per absorbed photon. For costs we considered the energy required for the synthesis of pigments, amino acids and proteins in each PSU. Our calculations indicate that AAP bacteria harvest more light energy than do PRP bacteria, but the costs of phototrophy are much higher for AAP bacteria. Still, the net energy gained by AAP bacteria is often sufficient to meet maintenance costs, while that is not the case for PRP bacteria except with high light intensities and large numbers of proteorhodopsin molecules per cell. The low costs and simplicity of PR-based phototrophy explain the high abundance of proteorhodopsin genes in the oceans. However, even for AAP bacteria, the net energy yield of phototrophy is apparently too low to influence the distribution of photoheterotrophic bacteria among various marine systems. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  1. Anoxygenic photosynthesis modulated Proterozoic oxygen and sustained Earth's middle age

    Science.gov (United States)

    Johnston, D. T.; Wolfe-Simon, F.; Pearson, A.; Knoll, A. H.

    2009-01-01

    Molecular oxygen (O2) began to accumulate in the atmosphere and surface ocean ca. 2,400 million years ago (Ma), but the persistent oxygenation of water masses throughout the oceans developed much later, perhaps beginning as recently as 580–550 Ma. For much of the intervening interval, moderately oxic surface waters lay above an oxygen minimum zone (OMZ) that tended toward euxinia (anoxic and sulfidic). Here we illustrate how contributions to primary production by anoxygenic photoautotrophs (including physiologically versatile cyanobacteria) influenced biogeochemical cycling during Earth's middle age, helping to perpetuate our planet's intermediate redox state by tempering O2 production. Specifically, the ability to generate organic matter (OM) using sulfide as an electron donor enabled a positive biogeochemical feedback that sustained euxinia in the OMZ. On a geologic time scale, pyrite precipitation and burial governed a second feedback that moderated sulfide availability and water column oxygenation. Thus, we argue that the proportional contribution of anoxygenic photosynthesis to overall primary production would have influenced oceanic redox and the Proterozoic O2 budget. Later Neoproterozoic collapse of widespread euxinia and a concomitant return to ferruginous (anoxic and Fe2+ rich) subsurface waters set in motion Earth's transition from its prokaryote-dominated middle age, removing a physiological barrier to eukaryotic diversification (sulfide) and establishing, for the first time in Earth's history, complete dominance of oxygenic photosynthesis in the oceans. This paved the way for the further oxygenation of the oceans and atmosphere and, ultimately, the evolution of complex multicellular organisms. PMID:19805080

  2. Origin of Bacteriochlorophyll a and the Early Diversification of Photosynthesis.

    Directory of Open Access Journals (Sweden)

    Tanai Cardona

    Full Text Available Photosynthesis originated in the domain Bacteria billions of years ago; however, the identity of the last common ancestor to all phototrophic bacteria remains undetermined and speculative. Here I present the evolution of BchF or 3-vinyl-bacteriochlorophyll hydratase, an enzyme exclusively found in bacteria capable of synthetizing bacteriochlorophyll a. I show that BchF exists in two forms originating from an early divergence, one found in the phylum Chlorobi, including its paralogue BchV, and a second form that was ancestral to the enzyme found in the remaining anoxygenic phototrophic bacteria. The phylogeny of BchF is consistent with bacteriochlorophyll a evolving in an ancestral phototrophic bacterium that lived before the radiation event that gave rise to the phylum Chloroflexi, Chlorobi, Acidobacteria, Proteobacteria, and Gemmatimonadetes, but only after the divergence of Type I and Type II reaction centers. Consequently, it is suggested that the lack of phototrophy in many groups of extant bacteria is a derived trait.

  3. Phototrophic microbes form endolithic biofilms in ikaite tufa columns (SW Greenland).

    Science.gov (United States)

    Trampe, Erik; Castenholz, Richard W; Larsen, Jens E N; Kühl, Michael

    2017-11-01

    Marine tufa-columns, formed by the hydrated carbonate mineral ikaite, present a unique alkaline microbial habitat only found in Ikka Fjord (SW-Greenland). The outermost parts of the ikaite columns exhibit a multitude of physico-chemical gradients, and the porous ikaite is colonized by endolithic phototrophic biofilms serving as a substrate for grazing epifauna, where scraping by sea urchins affects overall column-topography. We present a detailed study of the optical microenvironment, spatial organization, and photosynthetic activity of endolithic phototrophs within the porous ikaite crystal matrix. Cyanobacteria and diatoms formed distinctly coloured zones and were closely associated with ikaite-crystals via excretion of exopolymers. Scalar-irradiance measurements showed strong attenuation of visible light (400-700 nm), where only ∼1% of incident irradiance remained at 20 mm depth. Transmission spectra showed in vivo absorption signatures of diatom and cyanobacterial photopigments, which were confirmed by HPLC-analysis. Variable-chlorophyll-fluorescence-imaging showed active photosynthesis with high-light acclimation in the outer diatom layer, and low-light acclimation in the underlying cyanobacterial part. Phototrophs in ikaite thus thrive in polymer-bound endolithic biofilms in a complex gradient microhabitat experiencing constant slow percolation of highly alkaline phosphate-enriched spring water mixing with cold seawater at the tufa-column-apex. We discuss the potential role of these biofilms in ikaite column formation. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. Microscale Canopy Interactions in Aquatic Phototrophs

    DEFF Research Database (Denmark)

    Lichtenberg, Mads

    . This was investigated in a range of aquatic phototrophs such as macroalgae, reef-building corals, and photosynthetic biofilms. As a first step, we demonstrate that a microscale stratification of the internal light- and chemical environment exists across the investigated systems, with concomitant internal gradients...... of photosynthesis and respiration. We further investigate this by compiling a closed radiative energy budget of a coral and find that corals are highly efficient light collectors that can display photosynthetic quantum efficiencies close to the theoretical limit. Using a similar approach, we then investigate i) how...

  5. The diversity and abundance of bacteria and oxygenic phototrophs in saline biological desert crusts in Xinjiang, northwest China.

    Science.gov (United States)

    Li, Ke; Liu, Ruyin; Zhang, Hongxun; Yun, Juanli

    2013-07-01

    Although microorganisms, particularly oxygenic phototrophs, are known as the major players in the biogeochemical cycles of elements in desert soil ecosystems and have received extensive attention, still little is known about the effects of salinity on the composition and abundances of microbial community in desert soils. In this study, the diversity and abundance of bacteria and oxygenic phototrophs in biological desert crusts from Xinjiang province, which were under different salinity conditions, were investigated by using clone library and quantitative PCR (qPCR). The 16S rRNA gene phylogenetic analysis showed that cyanobacteria, mainly Microcoleus vagnitus of the order Oscillatoriales, were predominant in the low saline crusts, while other phototrophs, such as diatom, were the main microorganism group responsible for the oxygenic photosynthesis in the high saline crusts. Furthermore, the higher salt content in crusts may stimulate the growth of other bacteria, including Deinococcus-Thermus, Bacteroidetes, and some subdivisions of Proteobacteria (β-, γ-, and δ-Proteobacteria). The cpcBA-IGS gene analysis revealed the existence of novel M. vagnitus strains in this area. The qPCR results showed that the abundance of oxygenic phototrophs was significantly higher under lower saline condition than that in the higher saline crusts, suggesting that the higher salinity in desert crusts could suppress the numbers of total bacteria and phototrophic bacteria but did highly improve the diversity of salt-tolerant bacteria.

  6. Anthocyanin-dependent anoxygenic photosynthesis in coloured flower petals?

    Science.gov (United States)

    Lysenko, Vladimir; Varduny, Tatyana

    2013-11-01

    Chlorophylless flower petals are known to be composed of non-photosynthetic tissues. Here, we show that the light energy storage that can be photoacoustically measured in flower petals of Petunia hybrida is approximately 10-12%. We found that the supposed chlorophylless photosynthesis is an anoxygenic, anthocyanin-dependent process occurring in blue flower petals (ADAPFP), accompanied by non-respiratory light-dependent oxygen uptake and a 1.5-fold photoinduced increase in ATP levels. Using a simple, adhesive tape stripping technique, we have obtained a backside image of an intact flower petal epidermis, revealing sword-shaped ingrowths connecting the cell wall and vacuole, which is of interest for the further study of possible vacuole-related photosynthesis. Approaches to the interpretations of ADAPFP are discussed, and we conclude that these results are not impossible in terms of the known photochemistry of anthocyanins.

  7. Interactions between soil phototrophs and vascular plants in Himalayan cold deserts

    Czech Academy of Sciences Publication Activity Database

    Řeháková, Klára; Čapková, Kateřina; Dvorský, M.; Kopecký, M.; Altman, J.; Šmilauer, P.; Doležal, J.

    2017-01-01

    Roč. 115, Dec (2017), s. 568-578 ISSN 0038-0717 Institutional support: RVO:60077344 Keywords : cold desert * Himalaya * interactions * soil phototrophs Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.857, year: 2016

  8. Gain and loss of phototrophic genes revealed by comparison of two Citromicrobium bacterial genomes.

    Directory of Open Access Journals (Sweden)

    Qiang Zheng

    Full Text Available Proteobacteria are thought to have diverged from a phototrophic ancestor, according to the scattered distribution of phototrophy throughout the proteobacterial clade, and so the occurrence of numerous closely related phototrophic and chemotrophic microorganisms may be the result of the loss of genes for phototrophy. A widespread form of bacterial phototrophy is based on the photochemical reaction center, encoded by puf and puh operons that typically are in a 'photosynthesis gene cluster' (abbreviated as the PGC with pigment biosynthesis genes. Comparison of two closely related Citromicrobial genomes (98.1% sequence identity of complete 16S rRNA genes, Citromicrobium sp. JL354, which contains two copies of reaction center genes, and Citromicrobium strain JLT1363, which is chemotrophic, revealed evidence for the loss of phototrophic genes. However, evidence of horizontal gene transfer was found in these two bacterial genomes. An incomplete PGC (pufLMC-puhCBA in strain JL354 was located within an integrating conjugative element, which indicates a potential mechanism for the horizontal transfer of genes for phototrophy.

  9. Light structures phototroph, bacterial and fungal communities at the soil surface.

    Directory of Open Access Journals (Sweden)

    Lawrence O Davies

    Full Text Available The upper few millimeters of soil harbour photosynthetic microbial communities that are structurally distinct from those of underlying bulk soil due to the presence of light. Previous studies in arid zones have demonstrated functional importance of these communities in reducing soil erosion, and enhancing carbon and nitrogen fixation. Despite being widely distributed, comparative understanding of the biodiversity of the soil surface and underlying soil is lacking, particularly in temperate zones. We investigated the establishment of soil surface communities on pasture soil in microcosms exposed to light or dark conditions, focusing on changes in phototroph, bacterial and fungal communities at the soil surface (0-3 mm and bulk soil (3-12 mm using ribosomal marker gene analyses. Microbial community structure changed with time and structurally similar phototrophic communities were found at the soil surface and in bulk soil in the light exposed microcosms suggesting that light can influence phototroph community structure even in the underlying bulk soil. 454 pyrosequencing showed a significant selection for diazotrophic cyanobacteria such as Nostoc punctiforme and Anabaena spp., in addition to the green alga Scenedesmus obliquus. The soil surface also harboured distinct heterotrophic bacterial and fungal communities in the presence of light, in particular, the selection for the phylum Firmicutes. However, these light driven changes in bacterial community structure did not extend to the underlying soil suggesting a discrete zone of influence, analogous to the rhizosphere.

  10. A mass-spring model unveils the morphogenesis of phototrophic Diatoma biofilms

    NARCIS (Netherlands)

    Celler, K.; Hödl, I.; Simone, A.; Battin, T.J.; Picioreanu, C.

    2014-01-01

    Diatoms often dominate planktonic communities in the ocean and phototrophic biofilms in streams and rivers, greatly contributing to global biogeochemical fluxes. In pelagic ecosystems, these microscopic algae can form chain-like microcolonies, which seem advantageous for nutrient uptake and protect

  11. Cyanobacteria in sulfidic spring microbial mats can perform oxygenic and anoxygenic photosynthesis simultaneously during an entire diurnal period

    NARCIS (Netherlands)

    Klatt, Judith M.; de Beer, Dirk; Häusler, Stefan; Polerecky, Lubos|info:eu-repo/dai/nl/370827929

    2016-01-01

    We used microsensors to study the regulation of anoxygenic and oxygenic photosynthesis (AP and OP, respectively) by light and sulfide in a cyanobacterium dominating microbial mats from cold sulfidic springs. Both photosynthetic modes were performed simultaneously over all H2S concentrations (1–2200

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

    KAUST Repository

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

    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

  13. Modeling the Habitat Range of Phototrophic Microorganisms in Yellowstone National Park: Toward the Development of a Comprehensive Fitness Landscape

    Directory of Open Access Journals (Sweden)

    Eric eBoyd

    2012-06-01

    Full Text Available The extent to which geochemical variation constrains the distribution of phototrophic metabolisms was modeled based on 439 observations in geothermal springs in Yellowstone National Park (YNP, Wyoming. Generalized additive models (GAMs were developed to predict the distribution of photosynthesis as a function of spring temperature, pH, and total sulfide. GAMs comprised of temperature explained 42.7% of the variation in the distribution of phototrophic metabolisms whereas GAMs comprised of sulfide and pH explained 20.7% and 11.7% of the variation, respectively. These results suggest that of the measured variables, temperature is the primary constraint on the distribution of phototrophic metabolism in YNP. GAMs comprised of multiple variables explained a larger percentage of the variation in the distribution of phototrophic metabolism, indicating additive interactions among variables. A GAM that combined temperature and sulfide explained the greatest variation in the dataset (54.8% while minimizing the introduction of degrees of freedom. In an effort to verify the extent to which phototroph distribution reflects constraints on activity, we examined the influence of sulfide and temperature on dissolved inorganic carbon (DIC uptake rates under both light and dark conditions. Light-driven DIC uptake decreased systematically with increasing concentrations of sulfide in acidic, algal-dominated systems, but was unaffected in alkaline, bacterial-dominated systems. In both alkaline and acidic systems, light-driven DIC uptake was suppressed in cultures incubated at temperatures 10°C greater than their in situ temperature. Collectively, these results suggest that the habitat range of phototrophs in YNP springs, specifically that of cyanobacteria and algae, largely results from constraints imposed by temperature and sulfide on the activity and fitness of these populations, a finding that is consistent with the predictions from GAMs.

  14. Structural and functional analysis of a microbial mat ecosystem from a unique permanent hypersaline inland lake: 'La Salada de Chiprana' (NE Spain).

    Science.gov (United States)

    Jonkers, Henk M; Ludwig, Rebecca; Wit, Rutger; Pringault, Olivier; Muyzer, Gerard; Niemann, Helge; Finke, Niko; Beer, Dirk

    2003-05-01

    The benthic microbial mat community of the only permanent hypersaline natural inland lake of Western Europe, 'La Salada de Chiprana', northeastern Spain, was structurally and functionally analyzed. The ionic composition of the lake water is characterized by high concentrations of magnesium and sulfate, which were respectively 0.35 and 0.5 M at the time of sampling while the total salinity was 78 g l(-1). Community composition was analyzed by microscopy, high-performance liquid chromatography (HPLC) pigment analyses and by studying culturable bacteria from different functional groups. Therefore, denaturing gradient gel electrophoresis (DGGE) was applied on most probable number (MPN) dilution cultures. Microscopy revealed that a thin layer of Chloroflexus-like bacteria overlaid various cyanobacteria-dominated layers each characterized by different morphotypes. DGGE analysis of MPN dilution cultures from distinct mat layers showed that various phylotypes of anoxygenic phototrophic, aerobic heterotrophic, colorless sulfur-, and sulfate-reducing bacteria were present. The mats were furthermore functionally studied and attention was focussed on the relationship between oxygenic primary production and the flow of carbon through the microbial community. Microsensor techniques, porewater and sediment photopigment analysis were applied in order to estimate oxygenic photosynthetic rates, daily dynamics of (in)organic carbon porewater concentration and migration behavior of phototrophs. Chiprana microbial mats produced dissolved organic carbon (DOC) both during the day and night. It was estimated that 14% of the mats gross photosynthetic production and 49% of the mats net photosynthetic production diffused out of the mat in the form of low molecular mass fatty acids, although these compounds made up only 2% of the total DOC pool. The high flux of dissolved fatty acids from the microbial mat to the water column may explain why in this system Chloroflexus-like bacteria

  15. Rapid assessment of different oxygenic phototrophs and single-cell photosynthesis with multicolour variable chlorophyll fluorescence imaging

    DEFF Research Database (Denmark)

    Trampe, Erik Christian Løvbjerg; Kolbowski, J.; Schreiber, U.

    2011-01-01

    , red or white light. Automated sequential exposure of microscopic samples to the three excitation colours enables subsequent deconvolution of the resulting fluorescence signals and colour marking of cells with different photopigmentation, i.e., cyanobacteria, green algae, red algae and diatoms....... The photosynthetic activity in complex mixtures of phototrophs and natural samples can thus be assigned to different types of phototrophs, which can be quantified simultaneously. Here, we describe the composition and performance of the new imaging system and present applications with both natural phytoplankton...

  16. Cellulose degradation and assimilation by the unicellular phototrophic eukaryote Chlamydomonas reinhardtii.

    Science.gov (United States)

    Blifernez-Klassen, Olga; Klassen, Viktor; Doebbe, Anja; Kersting, Klaudia; Grimm, Philipp; Wobbe, Lutz; Kruse, Olaf

    2012-01-01

    Plants convert sunlight to biomass, which is primarily composed of lignocellulose, the most abundant natural biopolymer and a potential feedstock for fuel and chemical production. Cellulose assimilation has so far only been described for heterotrophic organisms that rely on photosynthetically active primary producers of organic compounds. Among phototrophs, the unicellular green microalga Chlamydomonas reinhardtii is widely known as one of the best established model organisms. It occupies many habitats, including aquatic and soil ecosystems. This ubiquity underscores the versatile metabolic properties of this microorganism. Here we present yet another paradigm of adaptation for C. reinhardtii, highlighting its photoheterotrophic ability to utilize cellulose for growth in the absence of other carbon sources. When grown under CO(2)-limiting conditions in the light, secretion of endo-β-1,4-glucanases by the cell causes digestion of exogenous cellulose, followed by cellobiose uptake and assimilation. Phototrophic microbes like C. reinhardtii may thus serve as biocatalysts for cellulosic biofuel production.

  17. Photosynthesis Is Widely Distributed among Proteobacteria as Demonstrated by the Phylogeny of PufLM Reaction Center Proteins

    Directory of Open Access Journals (Sweden)

    Johannes F. Imhoff

    2018-01-01

    Full Text Available Two different photosystems for performing bacteriochlorophyll-mediated photosynthetic energy conversion are employed in different bacterial phyla. Those bacteria employing a photosystem II type of photosynthetic apparatus include the phototrophic purple bacteria (Proteobacteria, Gemmatimonas and Chloroflexus with their photosynthetic relatives. The proteins of the photosynthetic reaction center PufL and PufM are essential components and are common to all bacteria with a type-II photosynthetic apparatus, including the anaerobic as well as the aerobic phototrophic Proteobacteria. Therefore, PufL and PufM proteins and their genes are perfect tools to evaluate the phylogeny of the photosynthetic apparatus and to study the diversity of the bacteria employing this photosystem in nature. Almost complete pufLM gene sequences and the derived protein sequences from 152 type strains and 45 additional strains of phototrophic Proteobacteria employing photosystem II were compared. The results give interesting and comprehensive insights into the phylogeny of the photosynthetic apparatus and clearly define Chromatiales, Rhodobacterales, Sphingomonadales as major groups distinct from other Alphaproteobacteria, from Betaproteobacteria and from Caulobacterales (Brevundimonas subvibrioides. A special relationship exists between the PufLM sequences of those bacteria employing bacteriochlorophyll b instead of bacteriochlorophyll a. A clear phylogenetic association of aerobic phototrophic purple bacteria to anaerobic purple bacteria according to their PufLM sequences is demonstrated indicating multiple evolutionary lines from anaerobic to aerobic phototrophic purple bacteria. The impact of pufLM gene sequences for studies on the environmental diversity of phototrophic bacteria is discussed and the possibility of their identification on the species level in environmental samples is pointed out.

  18. Photosynthetic versatility in the genome of Geitlerinema sp. PCC 9228 (formerly Oscillatoria limnetica ‘Solar Lake’, a model anoxygenic photosynthetic cyanobacterium

    Directory of Open Access Journals (Sweden)

    Sharon L Grim

    2016-10-01

    Full Text Available Anoxygenic cyanobacteria that use sulfide as the electron donor for photosynthesis are a potentially influential but poorly constrained force on Earth’s biogeochemistry. Their versatile metabolism may have boosted primary production and nitrogen cycling in euxinic coastal margins in the Proterozoic. In addition, they represent a biological mechanism for limiting the accumulation of atmospheric oxygen, especially before the Great Oxidation Event and in the low-oxygen conditions of the Proterozoic. In this study, we describe the draft genome sequence of Geitlerinema sp. PCC 9228, formerly Oscillatoria limnetica ‘Solar Lake’, a mat-forming diazotrophic cyanobacterium that can switch between oxygenic photosynthesis and sulfide-based anoxygenic photosynthesis. Geitlerinema possesses three variants of psbA, which encodes protein D1, a core component of the photosystem II reaction center. Phylogenetic analyses indicate that one variant is closely affiliated with cyanobacterial psbA genes that code for a D1 protein used for oxygen-sensitive processes. Another version is phylogenetically similar to cyanobacterial psbA genes that encode D1 proteins used under microaerobic conditions, and the third variant may be cued to high light and/or elevated oxygen concentrations. Geitlerinema has the canonical gene for sulfide quinone reductase (SQR used in cyanobacterial anoxygenic photosynthesis and a putative transcriptional regulatory gene in the same operon. Another operon with a second, distinct sqr and regulatory gene is present, and is phylogenetically related to sqr genes used for high sulfide concentrations. The genome has a comprehensive nif gene suite for nitrogen fixation, supporting previous observations of nitrogenase activity. Geitlerinema possesses a bidirectional hydrogenase rather than the uptake hydrogenase typically used by cyanobacteria in diazotrophy. Overall, the genome sequence of Geitlerinema sp. PCC 9228 highlights potential

  19. Phototrophy in Mildly Acidic Hot Spring Ecosystems

    Science.gov (United States)

    Fecteau, K.; Boyd, E. S.; Shock, E.

    2014-12-01

    Microbial light-driven reduction of carbon in continental hydrothermal ecosystems is restricted to environments at temperatures less than 73 °C. In circumneutral and alkaline systems bacterial phototrophs (cyanobacteria and anoxygenic phototrophs) are suggested to be principally responsible for this activity whereas algal (i.e., eukaryotic) phototrophs are thought to be responsible for this activity in acidic systems. In Yellowstone National Park numerous examples of phototrophic microbial communities exist at high and low pH, while hot springs with intermediate pH (values 3-5) are rare and commonly dilute. It is thought that the transition from algal photosynthesis to bacterial photosynthesis occurs within this pH range. To test this hypothesis, we sequenced bacterial and eukaryal small subunit ribosomal RNA genes, analyzed pigments, and performed comprehensive geochemical measurements from 12 hot springs within this pH realm. At all sites, the largest phototrophic population was either comprised of Cyanobacteria or affiliated with the algal order Cyanidiales, which are ubiquitous in acidic springs, yet abundant sequences of both lineages were present in 8 of the 12 sites. Nevertheless, some of these samples exceeded the known temperature limit of the algae (56 °C), suggesting that these populations are dead or inactive. Indeed, one site yielded evidence for a large Cyanidiales population as the only phototrophs present, yet an experiment at the time of sampling failed to demonstrate light-driven carbon fixation, and analysis of extracted pigments showed a large amount of the chlorophyll degradation product pheophorbide a and very little intact chlorophyll, indicating photosynthesis occurred at this site when conditions were different. Our observations illustrate the dynamic nature of these systems that may be transiently conducive to photosynthesis, which may open niches for phototrophs of both domains and likely played a role in the evolution of photosynthesis.

  20. The interaction of soil phototrophs and fungi with pH and their impact on soil CO2, CO18O and OCS exchange.

    Science.gov (United States)

    Sauze, Joana; Ogée, Jérôme; Maron, Pierre-Alain; Crouzet, Olivier; Nowak, Virginie; Wohl, Steven; Kaisermann, Aurore; Jones, Sam P; Wingate, Lisa

    2017-12-01

    The stable oxygen isotope composition of atmospheric CO 2 and the mixing ratio of carbonyl sulphide (OCS) are potential tracers of biospheric CO 2 fluxes at large scales. However, the use of these tracers hinges on our ability to understand and better predict the activity of the enzyme carbonic anhydrase (CA) in different soil microbial groups, including phototrophs. Because different classes of the CA family (α, β and γ) may have different affinities to CO 2 and OCS and their expression should also vary between different microbial groups, differences in the community structure could impact the 'community-integrated' CA activity differently for CO 2 and OCS. Four soils of different pH were incubated in the dark or with a diurnal cycle for forty days to vary the abundance of native phototrophs. Fluxes of CO 2 , CO 18 O and OCS were measured to estimate CA activity alongside the abundance of bacteria, fungi and phototrophs. The abundance of soil phototrophs increased most at higher soil pH. In the light, the strength of the soil CO 2 sink and the CA-driven CO 2 -H 2 O isotopic exchange rates correlated with phototrophs abundance. OCS uptake rates were attributed to fungi whose abundance was positively enhanced in alkaline soils but only in the presence of increased phototrophs. Our findings demonstrate that soil-atmosphere CO 2 , OCS and CO 18 O fluxes are strongly regulated by the microbial community structure in response to changes in soil pH and light availability and supports the idea that different members of the microbial community express different classes of CA, with different affinities to CO 2 and OCS.

  1. Carbon metabolic pathways in phototrophic bacteria and their broader evolutionary implications

    Directory of Open Access Journals (Sweden)

    Kuo-Hsiang eTang

    2011-08-01

    Full Text Available Photosynthesis is the biological process that converts solar energy to biomass, bio-products and biofuel. It is the only major natural solar energy storage mechanism on Earth. To satisfy the increased demand for sustainable energy sources and identify the mechanism of photosynthetic carbon assimilation, which is one of the bottlenecks in photosynthesis, it is essential to understand the process of solar energy storage and associated carbon metabolism in photosynthetic organisms. Researchers have employed physiological studies, microbiological chemistry, enzyme assays, genome sequencing, transcriptomics, and 13C-based metabolomics/fluxomics to investigate central carbon metabolism and enzymes that operate in phototrophs. In this report, we review diverse CO2 assimilation pathways, acetate assimilation, carbohydrate catabolism, the TCA cycle and some key and/or unconventional enzymes in central carbon metabolism of phototrophic microorganisms. We also discuss the reducing equivalent flow during photoautotrophic and photoheterotrophic growth, evolutionary links in the central carbon metabolic network, and correlations between photosynthetic and non-photosynthetic organisms. Considering the metabolic versatility in these fascinating and diverse photosynthetic bacteria, many essential questions in their central carbon metabolism still remain to be addressed.

  2. Molecular characterization of phototrophic microorganisms in the forefield of a receding glacier in the Swiss Alps

    Science.gov (United States)

    Frey, Beat; Bühler, Lukas; Schmutz, Stefan; Zumsteg, Anita; Furrer, Gerhard

    2013-03-01

    Recently deglaciated areas are ideal environments to study soil formation and primary microbial succession where phototrophic microorganisms may play a role as primary producers. The aim of our study was to investigate the cyanobacterial and green algal community composition in three different successional stages of the Damma glacier forefield in the Swiss Alps using 16S rDNA and ITS rDNA clone libraries. Cyanobacterial target sequences varied along the glacier forefield, with the highest cyanobacterial 16S rRNA gene copies found in sparsely vegetated soils. Sequence analysis revealed that the phototrophic communities were distinct in each of the three soil environments. The majority of the cyanobacterial sequences retrieved from barren soils were related to the Oscillatoriales. The diversity in sparsely vegetated soils was low, and sequences closely related to Nostoc sp. dominated. The majority of the algal phylotypes are related to members of the Trebouxiophyceae known to live as symbiotic partners in lichens. We conclude that the community composition appears to shift markedly along the chronosequence, indicating that each soil environment selects for its phototrophic community. When cyanobacteria occur together with eukaryotic microalgae, they form a rich source of organic matter and may be important contributors of carbon in nutrient-deficient deglaciated soils.

  3. Molecular characterization of phototrophic microorganisms in the forefield of a receding glacier in the Swiss Alps

    International Nuclear Information System (INIS)

    Frey, Beat; Bühler, Lukas; Schmutz, Stefan; Zumsteg, Anita; Furrer, Gerhard

    2013-01-01

    Recently deglaciated areas are ideal environments to study soil formation and primary microbial succession where phototrophic microorganisms may play a role as primary producers. The aim of our study was to investigate the cyanobacterial and green algal community composition in three different successional stages of the Damma glacier forefield in the Swiss Alps using 16S rDNA and ITS rDNA clone libraries. Cyanobacterial target sequences varied along the glacier forefield, with the highest cyanobacterial 16S rRNA gene copies found in sparsely vegetated soils. Sequence analysis revealed that the phototrophic communities were distinct in each of the three soil environments. The majority of the cyanobacterial sequences retrieved from barren soils were related to the Oscillatoriales. The diversity in sparsely vegetated soils was low, and sequences closely related to Nostoc sp. dominated. The majority of the algal phylotypes are related to members of the Trebouxiophyceae known to live as symbiotic partners in lichens. We conclude that the community composition appears to shift markedly along the chronosequence, indicating that each soil environment selects for its phototrophic community. When cyanobacteria occur together with eukaryotic microalgae, they form a rich source of organic matter and may be important contributors of carbon in nutrient-deficient deglaciated soils. (letter)

  4. Genomic analysis reveals key aspects of prokaryotic symbiosis in the phototrophic consortium "Chlorochromatium aggregatum"

    DEFF Research Database (Denmark)

    Liu, Zhenfeng; Müller, Johannes; Li, Tao

    2013-01-01

    'Chlorochromatium aggregatum' is a phototrophic consortium, a symbiosis that may represent the highest degree of mutual interdependence between two unrelated bacteria not associated with a eukaryotic host. 'Chlorochromatium aggregatum' is a motile, barrel-shaped aggregate formed from a single cell...

  5. NATURAL ANTIBIOFOULING AGENTS AS NEW CONTROL METHOD FOR PHOTOTROPHIC BIOFILMS DWELLING ON MONUMENTAL STONE SURFACES

    Directory of Open Access Journals (Sweden)

    Oana-Adriana CUZMAN

    2011-03-01

    Full Text Available Five natural antibiofoulants with terrestrial (capsaicine - CS, cinnamaldehyde - CI and marine origin (zosteric acid - ZA, poly-alkylpyridinium salts - pAPS and Ceramium botryocarpum extract - CBE have been selected and tested against phototrophic biofilm formation on the stone surfaces for their inhibitory properties. The antibiofouling agents (ABAs were incorporated into two commercial silicone based coatings (Silres BS OH 100 - S and Silres BS 290 - W. In this work, phototrophic growth was evaluated by epifluorescence microscopy and semi-quantitative image analysis. The results showed an inhibitory efficiency for almost all tested ABAs. However, this efficiency has been found for short time or when the incorporating agent were incompletely cured. Among the ABAs tested, the poly-alkylpyridinium salts and cinnamaldehyde incorporated into Silres BS 290 showed the best inhibitory efficiency.

  6. Towards long-read metagenomics: complete assembly of three novel genomes from bacteria dependent on a diazotrophic cyanobacterium in a freshwater lake co-culture.

    Science.gov (United States)

    Driscoll, Connor B; Otten, Timothy G; Brown, Nathan M; Dreher, Theo W

    2017-01-01

    Here we report three complete bacterial genome assemblies from a PacBio shotgun metagenome of a co-culture from Upper Klamath Lake, OR. Genome annotations and culture conditions indicate these bacteria are dependent on carbon and nitrogen fixation from the cyanobacterium Aphanizomenon flos-aquae, whose genome was assembled to draft-quality . Due to their taxonomic novelty relative to previously sequenced bacteria, we have temporarily designated these bacteria as incertae sedis Hyphomonadaceae strain UKL13-1 (3,501,508 bp and 56.12% GC), incertae sedis Betaproteobacterium strain UKL13-2 (3,387,087 bp and 54.98% GC), and incertae sedis Bacteroidetes strain UKL13-3 (3,236,529 bp and 37.33% GC). Each genome consists of a single circular chromosome with no identified plasmids. When compared with binned Illumina assemblies of the same three genomes, there was ~7% discrepancy in total genome length. Gaps where Illumina assemblies broke were often due to repetitive elements. Within these missing sequences were essential genes and genes associated with a variety of functional categories. Annotated gene content reveals that both Proteobacteria are aerobic anoxygenic phototrophs, with Betaproteobacterium UKL13-2 potentially capable of phototrophic oxidation of sulfur compounds. Both proteobacterial genomes contain transporters suggesting they are scavenging fixed nitrogen from A. flos-aquae in the form of ammonium. Bacteroidetes UKL13-3 has few completely annotated biosynthetic pathways, and has a comparatively higher proportion of unannotated genes. The genomes were detected in only a few other freshwater metagenomes, suggesting that these bacteria are not ubiquitous in freshwater systems. Our results indicate that long-read sequencing is a viable method for sequencing dominant members from low-diversity microbial communities, and should be considered for environmental metagenomics when conditions meet these requirements.

  7. Environmental drivers of phototrophic biofilms in an Alpine show cave (SW-Italian Alps)

    International Nuclear Information System (INIS)

    Piano, E.; Bona, F.; Falasco, E.; La Morgia, V.; Badino, G.; Isaia, M.

    2015-01-01

    The proliferation of lampenflora is a major threat for the conservation of show caves, since phototrophic organisms cause physical, chemical and aesthetic damage to speleothems. In this paper we examine the environmental factors influencing the presence and the growth of the three main photosynthetic groups composing phototrophic biofilms in the Bossea show cave (SW-Italian Alps). The presence and the primary production of cyanobacteria, diatoms and green algae were detected with BenthoTorch®, an instrument for in situ measurement of chlorophyll a concentration that has never been used before in caves. By means of different techniques of regression analysis, we highlighted the response of the three photosynthetic groups to different environmental factors. Illuminance proved to be the main factor influencing positively both the probability of the presence and the productivity of the three groups. The presence of seeping water on the substrate and the distance from the cave entrance proved to play an important role in determining patterns of colonization. By means of GIS techniques, we provide thematic maps of the cave, providing a representation of pattern of the density of the three examined photosynthetic groups within different areas of the cave. The same approach may apply to other show caves, aiming at providing suggestions for the cave management (i.e. cleaning of the cave walls and positioning of artificial lights) and reduce impact caused by tourism. - Highlights: • We used a PAM fluorimeter on autotrophic biofilms in a show cave for the first time. • We modelled the environmental factors influencing phototrophic biofilms. • Illuminance, moisture and distance from the entrance proved to be significant. • We produced thematic maps illustrating our results. • We provide suggestions for cave management

  8. Environmental drivers of phototrophic biofilms in an Alpine show cave (SW-Italian Alps)

    Energy Technology Data Exchange (ETDEWEB)

    Piano, E., E-mail: elena.piano@unito.it [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy); Bona, F.; Falasco, E. [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy); La Morgia, V. [ISPRA, via Ca' Fornacetta, 9, 40064 Ozzano dell' Emilia (Italy); Badino, G. [Department of Physics, University of Turin, Via P. Giuria 1, 10125 Turin (Italy); Isaia, M. [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy)

    2015-12-01

    The proliferation of lampenflora is a major threat for the conservation of show caves, since phototrophic organisms cause physical, chemical and aesthetic damage to speleothems. In this paper we examine the environmental factors influencing the presence and the growth of the three main photosynthetic groups composing phototrophic biofilms in the Bossea show cave (SW-Italian Alps). The presence and the primary production of cyanobacteria, diatoms and green algae were detected with BenthoTorch®, an instrument for in situ measurement of chlorophyll a concentration that has never been used before in caves. By means of different techniques of regression analysis, we highlighted the response of the three photosynthetic groups to different environmental factors. Illuminance proved to be the main factor influencing positively both the probability of the presence and the productivity of the three groups. The presence of seeping water on the substrate and the distance from the cave entrance proved to play an important role in determining patterns of colonization. By means of GIS techniques, we provide thematic maps of the cave, providing a representation of pattern of the density of the three examined photosynthetic groups within different areas of the cave. The same approach may apply to other show caves, aiming at providing suggestions for the cave management (i.e. cleaning of the cave walls and positioning of artificial lights) and reduce impact caused by tourism. - Highlights: • We used a PAM fluorimeter on autotrophic biofilms in a show cave for the first time. • We modelled the environmental factors influencing phototrophic biofilms. • Illuminance, moisture and distance from the entrance proved to be significant. • We produced thematic maps illustrating our results. • We provide suggestions for cave management.

  9. Whole-genome sequence of a freshwater aerobic anoxygenic phototroph, Porphyrobacter sp. strain AAP82, isolated from the Huguangyan Maar Lake in Southern China

    Czech Academy of Sciences Publication Activity Database

    Li, X.; Koblížek, Michal; Feng, F.; Li, Y.; Jian, J.; Zeng, Yonghui

    2013-01-01

    Roč. 1, č. 2 (2013) ISSN 2169-8287 R&D Projects: GA ČR GAP501/10/0221; GA MŠk(CZ) ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : Porphyrobacter * Huguangyan Maar Lake Subject RIV: EE - Microbiology, Virology http://genomea. asm .org/content/1/2/e00072-13.full

  10. Whole-Genome Sequences of an Aerobic Anoxygenic Phototroph, Blastomonas sp. Strain AAP53, Isolated from a Freshwater Desert Lake in Inner Mongolia, China

    Czech Academy of Sciences Publication Activity Database

    Zeng, Yonghui; Koblížek, Michal; Feng, F.; Liu, Y.; Wu, Z.; Jian, J.

    2013-01-01

    Roč. 1, č. 2 (2013) ISSN 2169-8287 R&D Projects: GA ČR GAP501/10/0221; GA MŠk(CZ) ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : Blastomonas * Genome sequence Subject RIV: EE - Microbiology, Virology http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3622956/

  11. Exploring the secrets of the three-dimensional architecture of phototrophic biofilms in caves

    Directory of Open Access Journals (Sweden)

    Roldàn Monica

    2009-01-01

    Full Text Available Caves with dim natural light, and lighted hypogean environments, have been found to host phototrophic microorganisms from varioustaxonomic groups. These microorganisms group themselves into assemblies known as communities or biofilms, which are associated withrock surfaces. In this work, the phototrophic biofilms that colonise speleothems, walls and floors in three tourist caves (Spain were studied.Confocal laser scanning microscopy (CLSM and scanning electron microscopy (SEM were used to study these organisms and acquirethree-dimensional data on their biofilm structure. CLSM was used in a multi-channel mode whereby the different channels map individualbiofilm components. Cyanobacteria, green microalgae, diatoms, mosses and lichens were found to be grouped as biofilms that differedaccording to the sampling sites. The biofilms were classified into six types regarding their environmental conditions. These types weredefined by their constituent organisms, the thickness of their photosynthetic layers and their structure. Light-related stress is associated with lower biofilm thickness and species diversity, as is low humidity, and, in the case of artificially illuminated areas, the duration of lightexposure.

  12. Combining sedimentological, trace metal (Mn, Mo) and molecular evidence for reconstructing past water-column redox conditions: The example of meromictic Lake Cadagno (Swiss Alps)

    DEFF Research Database (Denmark)

    Wirth, S. B.; Gilli, A.; Niemann, H.

    2013-01-01

    reducing conditions and subsequent rapid precipitation of Mn-(oxyhydr) oxide minerals during episodic and short-term water-column mixing events mainly due to flood-induced underflows. At 9800 +/- 130 cal yr BP, a rapid transition to fully sulfidic conditions is indicated by the marked enrichment of Mo......-transition period beginning shortly after the lake formation similar to 12.5 kyr ago. The oxic period is characterized by low sedimentary Mn and Mo concentrations, as well as by the absence of any remnants of anoxygenic phototrophic sulfur bacteria. Enhanced accumulation/preservation of Mn (up to 5.6 wt...

  13. The evolution of glutathione metabolism in phototrophic microorganisms

    Science.gov (United States)

    Fahey, R. C.; Buschbacher, R. M.; Newton, G. L.

    1987-01-01

    Of the many roles ascribed to glutathione (GSH) the one most clearly established is its role in the protection of higher eucaryotes against oxygen toxicity through destruction of thiol-reactive oxygen byproducts. If this is the primary function of GSH then GSH metabolism should have evolved during or after the evolution of oxygenic photosynthesis. That many bacteria do not produce GSH is consistent with this view. In the present study we have examined the low-molecular-weight thiol composition of a variety of phototrophic microorganisms to ascertain how evolution of GSH production is related to evolution of oxygenic photosynthesis. Cells were extracted in the presence of monobromobimane (mBBr) to convert thiols to fluorescent derivatives, which were analyzed by high-pressure liquid chromatography. Significant levels of GSH were not found in the green bacteria (Chlorobium thiosulfatophilum and Chloroflexus aurantiacus). Substantial levels of GSH were present in the purple bacteria (Chromatium vinosum, Rhodospirillum rubrum, Rhodobacter sphaeroides, and Rhodocyclus gelatinosa), the cyanobacteria [Anacystis nidulans, Microcoleus chthonoplastes S.G., Nostoc muscorum, Oscillatoria amphigranulata, Oscillatoria limnetica, Oscillatoria sp. (Stinky Spring, Utah), Oscillatoria terebriformis, Plectonema boryanum, and Synechococcus lividus], and eucaryotic algae (Chlorella pyrenoidsa, Chlorella vulgaris, Euglena gracilis, Scenedesmus obliquus, and Chlamydomonas reinhardtii). Other thiols measured included cysteine, gamma-glutamylcysteine, thiosulfate, coenzyme A, and sulfide; several unidentified thiols were also detected. Many of the organisms examined also exhibited a marked ability to reduce mBBr to syn-(methyl,methyl)bimane, an ability that was quenched by treatment with 2-pyridyl disulfide or 5,5'-bisdithio-(2-nitrobenzoic acid) prior to reaction with mBBr. These observations indicate the presence of a reducing system capable of electron transfer to mBBr and reduction of

  14. Ultrafast excited state processes in Roseobacter denitrificans antennae: comparison of isolated complexes and native membranes

    NARCIS (Netherlands)

    Ferretti, M.; Duquesne, K.; Sturgis, J.N.; van Grondelle, R.

    2014-01-01

    Roseobacter (Rsb.) denitrificans is a marine aerobic anoxygenic photosynthetic purple bacterium with an unusually high-800 nm absorption band. Ultrafast excited state processes have been intensively studied in the past in order to understand why the energy transfer efficiency between photosynthetic

  15. Phaeobacterium nitratireducens gen. nov., sp. nov., a phototrophic gammaproteobacterium isolated from a mangrove forest sediment sample

    Digital Repository Service at National Institute of Oceanography (India)

    Nupur, P.; Srinivas, T.N.R.; Takaichi, S.; AnilKumar, P.

    A novel brown-coloured, Gram-negative-staining, rod-shaped, motile, phototrophic, purple sulfur bacterium, designated strain AK40T , was isolated in pure culture from a sediment sample collected from Coringa mangrove forest, India. Strain...

  16. Photosynthetic Versatility in the Genome of Geitlerinema sp. PCC 9228 (Formerly Oscillatoria limnetica 'Solar Lake'), a Model Anoxygenic Photosynthetic Cyanobacterium.

    Science.gov (United States)

    Grim, Sharon L; Dick, Gregory J

    2016-01-01

    Anoxygenic cyanobacteria that use sulfide as the electron donor for photosynthesis are a potentially influential but poorly constrained force on Earth's biogeochemistry. Their versatile metabolism may have boosted primary production and nitrogen cycling in euxinic coastal margins in the Proterozoic. In addition, they represent a biological mechanism for limiting the accumulation of atmospheric oxygen, especially before the Great Oxidation Event and in the low-oxygen conditions of the Proterozoic. In this study, we describe the draft genome sequence of Geitlerinema sp. PCC 9228, formerly Oscillatoria limnetica 'Solar Lake', a mat-forming diazotrophic cyanobacterium that can switch between oxygenic photosynthesis and sulfide-based anoxygenic photosynthesis (AP). Geitlerinema possesses three variants of psbA , which encodes protein D1, a core component of the photosystem II reaction center. Phylogenetic analyses indicate that one variant is closely affiliated with cyanobacterial psbA genes that code for a D1 protein used for oxygen-sensitive processes. Another version is phylogenetically similar to cyanobacterial psbA genes that encode D1 proteins used under microaerobic conditions, and the third variant may be cued to high light and/or elevated oxygen concentrations. Geitlerinema has the canonical gene for sulfide quinone reductase (SQR) used in cyanobacterial AP and a putative transcriptional regulatory gene in the same operon. Another operon with a second, distinct sqr and regulatory gene is present, and is phylogenetically related to sqr genes used for high sulfide concentrations. The genome has a comprehensive nif gene suite for nitrogen fixation, supporting previous observations of nitrogenase activity. Geitlerinema possesses a bidirectional hydrogenase rather than the uptake hydrogenase typically used by cyanobacteria in diazotrophy. Overall, the genome sequence of Geitlerinema sp. PCC 9228 highlights potential cyanobacterial strategies to cope with fluctuating

  17. Quantification of two forms of green sulfur bacteria in their natural habitat using bacteriochlorophyll fluorescence spectra

    Science.gov (United States)

    Kharcheva, Anastasia V.; Zhiltsova, Anna A.; Lunina, Olga N.; Savvichev, Alexander S.; Patsaeva, Svetlana V.

    2016-04-01

    Detection of phototropic organisms in their natural habitat using optical instruments operating under water is urgently needed for many tasks of ecological monitoring. While fluorescence methods are widely applied nowadays to detect and characterize phytoplankton communities, the techniques for detection and recognition of anoxygenic phototrophs are considered challenging. Differentiation of the forms of anoxygenic green sulfur bacteria in natural water using spectral techniques remains problematic. Green sulfur bacteria could be found in two forms, green-colored (containing BChl d in pigment compound) and brown-colored (containing BChl e), have the special ecological niche in such reservoirs. Separate determination of these microorganisms by spectral methods is complicated because of similarity of spectral characteristics of their pigments. We describe the novel technique of quantification of two forms of green sulfur bacteria directly in water using bacteriochlorophyll fluorescence without pigment extraction. This technique is noninvasive and could be applied in remote mode in the water bodies with restricted water circulation to determine simultaneously concentrations of two forms of green sulfur bacteria in their natural habitat.

  18. Photosynthetic Versatility in the Genome of Geitlerinema sp. PCC 9228 (Formerly Oscillatoria limnetica ?Solar Lake?), a Model Anoxygenic Photosynthetic Cyanobacterium

    OpenAIRE

    Grim, Sharon L.; Dick, Gregory J.

    2016-01-01

    Anoxygenic cyanobacteria that use sulfide as the electron donor for photosynthesis are a potentially influential but poorly constrained force on Earth’s biogeochemistry. Their versatile metabolism may have boosted primary production and nitrogen cycling in euxinic coastal margins in the Proterozoic. In addition, they represent a biological mechanism for limiting the accumulation of atmospheric oxygen, especially before the Great Oxidation Event and in the low-oxygen conditions of the Proteroz...

  19. A comparative ToF-SIMS and GC–MS analysis of phototrophic communities collected from an alkaline silica-depositing hot spring

    Energy Technology Data Exchange (ETDEWEB)

    Siljeström, S.; Parenteau, M. N.; Jahnke, L. L.; Cady, S. L.

    2017-07-01

    One of few techniques that is able to spatially resolve chemical data, including organic molecules, to morphological features in modern and ancient geological samples, is time-of-flight secondary ion mass spectrometry (ToF-SIMS). The ability to connect chemical data to morphology is key for interpreting the biogenicity of preserved remains in ancient samples. However, due to the lack of reference data for geologically relevant samples and the ease with which samples can be contaminated, ToF-SIMS data may be difficult to interpret. In this project, we aimed to build a ToF-SIMS spectral database by performing parallel ToF-SIMS and gas chromatography–mass spectrometry (GC–MS) analyses of extant photosynthetic microbial communities collected from an alkaline silica-depositing hot spring in Yellowstone National Park, USA. We built the library by analyzing samples of increasing complexity: pure lipid standards commonly found in thermophilic phototrophs, solvent extracts of specific lipid fractions, total lipid extracts, pure cultures of dominant phototrophic community members, and unsilicified phototrophic streamer communities. The results showed that important lipids and pigments originating from phototrophs were detected by ToF-SIMS (e.g., wax esters, monogalactosyldiacylglycerol, digalactosyldiacylglycerol, sufloquinovosyldiaglycerol, alkanes, etc.) in the streamer lipid extracts. Many of the lipids were also detected in situ in the unsilicified streamer, and could even be spatially resolved to individual cells within the streamer community. Together with the ToF-SIMS database, this mapping ability will be used to further explore other microbial mats and their fossilized counterparts in the geological record. This is likely to expand the geochemical understanding of these types of samples.

  20. The effect of harvesting on biomass production and nutrient removal in phototrophic biofilm reactors for effluent polishing

    NARCIS (Netherlands)

    Boelee, N.C.; Janssen, M.; Temmink, H.; Taparaviciute, L.; Khiewwijit, R.; Janoska, A.; Buisman, C.J.N.; Wijffels, R.H.

    2014-01-01

    An increasing number of wastewater treatment plants require post-treatment to remove residual nitrogen and phosphorus. This study investigated various harvesting regimes that would achieve consistent low effluent concentrations of nitrogen and phosphorus in a phototrophic biofilm reactor.

  1. Iron, Sulfur, Arsenic and Water: Geochemical Implications of Facultative Anoxygenic Photosynthesis in Cyanobacteria and the Slow Rise of Oxygen

    Science.gov (United States)

    Wolfe-Simon, F.; Johnston, D. T.; Girguis, P. R.; Pearson, A.; Knoll, A. H.

    2008-12-01

    Over geologic time, the global rise in atmospheric oxygen (O2) is attributed to the evolution and wide spread proliferation of oxygenic photosynthesis in cyanobacteria. However, cyanobacteria maintain a metabolic flexibility that may not always result in O2 release. Specifically, cyanobacteria can use a variety of alternative electron donors, rather than water, that are also readily oxidized. These may include sulfur, iron, and arsenic. Cyanobacteria are thus not uniquely constrained towards O2 production. Changes in the bioavailability of these key elements may have had dramatic consequences for and resulted in the slow accumulation of O2 in the atmosphere. In particular, by using facultative anoxygenic photosynthesis the cells maintain advantageous anaerobic conditions for N2-fixation. Although other types of bacteria are capable of N2-fixation, cyanobacteria singularly possess the dynamic capability of generating and surviving O2. These two processes "pull" the cells in opposite directions, metabolically speaking, around an aerobic-anaerobic continuum. Such a strategy also confers a distinct competitive advantage for cyanobacteria over photosynthetic eukaryotes, as they can endure widespread euxinia and maintain their cellular N quota. In an anoxic and/or sulfidic ocean, cyanobacteria would be expected to dominate over eukaryotic algae. Here we present Bayesian constructed phylogenetic distribution of specific genes and the metabolic role of key enzymes that form the basis of this hypothesis. We further suggest that the consequences of this proposed ecosystem structure altered the redox balance of the fluid Earth (atmosphere and oceans) and can help explain the observed long-term geochemical stasis and slow rates of eukaryotic diversification. We suggest that the underlying control for global oxygenation was a synergistic interplay between the evolution and elastic physiology of cyanobacteria as they impacted the redox state of early Earth.

  2. Isolation of a significant fraction of non-phototroph diversity from a desert Biological Soil Crust

    Directory of Open Access Journals (Sweden)

    Ulisses eNunes da Rocha

    2015-04-01

    Full Text Available Biological Soil Crusts (BSCs are organosedimentary assemblages comprised of microbes and minerals in topsoil of terrestrial environments. BSCs strongly impact soil quality in dryland ecosystems (e.g., soil structure and nutrient yields due to pioneer species such as Microcoleus vaginatus; phototrophs that produce filaments that bind the soil together, and support an array of heterotrophic microorganisms. These microorganisms in turn contribute to soil stability and biogeochemistry of BSCs. Non-cyanobacterial populations of BSCs are less well known than cyanobacterial populations. Therefore, we attempted to isolate a broad range of numerically significant and phylogenetically representative BSC aerobic heterotrophs. Combining simple pre-treatments (hydration of BSCs under dark and light and isolation strategies (media with varying nutrient availability and protection from oxidative stress we recovered 402 bacterial and one fungal isolate in axenic culture, which comprised 116 phylotypes (at 97% 16S rRNA gene sequence homology, 115 bacterial and one fungal. Each medium enriched a mostly distinct subset of phylotypes, and cultivated phylotypes varied due to the BSC pre-treatment. The fraction of the total phylotype diversity isolated, weighted by relative abundance in the community, was determined by the overlap between isolate sequences and OTUs reconstructed from metagenome or metatranscriptome reads. Together, more than 8% of relative abundance of OTUs in the metagenome was represented by our isolates, a cultivation efficiency much larger than typically expected from most soils. We conclude that simple cultivation procedures combined with specific pre-treatment of samples afford a significant reduction in the culturability gap, enabling physiological and metabolic assays that rely on ecologically relevant axenic cultures.

  3. Nutrient Removal and Biomass Production in an Outdoor Pilot-Scale Phototrophic Biofilm Reactor for Effluent Polishing

    NARCIS (Netherlands)

    Boelee, N.C.; Janssen, M.; Temmink, H.; Shrestha, R.; Buisman, C.J.N.; Wijffels, R.H.

    2014-01-01

    An innovative pilot-scale phototrophic biofilm reactor was evaluated over a 5-month period to determine its capacity to remove nitrogen and phosphorus from Dutch municipal wastewater effluents. The areal biomass production rate ranged between 2.7 and 4.5 g dry weight/m2/day. The areal nitrogen and

  4. Photosynthetic Versatility in the Genome of Geitlerinema sp. PCC 9228 (Formerly Oscillatoria limnetica ‘Solar Lake’), a Model Anoxygenic Photosynthetic Cyanobacterium

    Science.gov (United States)

    Grim, Sharon L.; Dick, Gregory J.

    2016-01-01

    Anoxygenic cyanobacteria that use sulfide as the electron donor for photosynthesis are a potentially influential but poorly constrained force on Earth’s biogeochemistry. Their versatile metabolism may have boosted primary production and nitrogen cycling in euxinic coastal margins in the Proterozoic. In addition, they represent a biological mechanism for limiting the accumulation of atmospheric oxygen, especially before the Great Oxidation Event and in the low-oxygen conditions of the Proterozoic. In this study, we describe the draft genome sequence of Geitlerinema sp. PCC 9228, formerly Oscillatoria limnetica ‘Solar Lake’, a mat-forming diazotrophic cyanobacterium that can switch between oxygenic photosynthesis and sulfide-based anoxygenic photosynthesis (AP). Geitlerinema possesses three variants of psbA, which encodes protein D1, a core component of the photosystem II reaction center. Phylogenetic analyses indicate that one variant is closely affiliated with cyanobacterial psbA genes that code for a D1 protein used for oxygen-sensitive processes. Another version is phylogenetically similar to cyanobacterial psbA genes that encode D1 proteins used under microaerobic conditions, and the third variant may be cued to high light and/or elevated oxygen concentrations. Geitlerinema has the canonical gene for sulfide quinone reductase (SQR) used in cyanobacterial AP and a putative transcriptional regulatory gene in the same operon. Another operon with a second, distinct sqr and regulatory gene is present, and is phylogenetically related to sqr genes used for high sulfide concentrations. The genome has a comprehensive nif gene suite for nitrogen fixation, supporting previous observations of nitrogenase activity. Geitlerinema possesses a bidirectional hydrogenase rather than the uptake hydrogenase typically used by cyanobacteria in diazotrophy. Overall, the genome sequence of Geitlerinema sp. PCC 9228 highlights potential cyanobacterial strategies to cope with

  5. Treatment of hydrocarbon-rich wastewater using oil degrading bacteria and phototrophic microorganisms in rotating biological contactor: Effect of N:P ratio

    International Nuclear Information System (INIS)

    Chavan, Anal; Mukherji, Suparna

    2008-01-01

    Treatment of hydrocarbon-rich industrial wastewater in bioreactors using heterotrophic microorganisms is often associated with various operational problems. In this study, a consortium of phototrophic microorganisms and a bacterium is developed on the discs of a rotating biological contactor (RBC) for treatment of wastewater containing diesel oil. The reactor was fed with oil degrading bacterium, Burkholderia cepacia and oil tolerant phototrophic microorganisms. After biofilm formation and acclimatization to 0.6% (v/v) diesel, continuous-mode operation was initiated at 21 h hydraulic retention time (HRT). Residual diesel in the effluent was 0.003%. Advantages of this system include good total petroleum hydrocarbon (TPH) removal, no soluble carbon source requirement and good settleability of biosolids. Biofilm observations revealed the predominance of B. cepacia and cyanobacteria (Phormidium, Oscillatoria and Chroococcus). The N:P ratio affected the relative dominance of the phototrophic microorganisms and bacterial culture. This ratio was a critical factor in determining the performance efficiency of the reactor. At 21 h HRT and organic loading of 27.33 g TPH/m 2 d, the N:P ratio 28.5:1 and 38:1 both yielded high and almost comparable TPH and COD removal efficiencies. This study presents a feasible technology for the treatment of hydrocarbon-rich wastewater from petrochemical industries and petroleum refineries

  6. Temperature modulates phototrophic periphyton response to chronic copper exposure

    International Nuclear Information System (INIS)

    Lambert, Anne Sophie; Dabrin, Aymeric; Morin, Soizic; Gahou, Josiane; Foulquier, Arnaud; Coquery, Marina; Pesce, Stéphane

    2016-01-01

    Streams located in vineyard areas are highly prone to metal pollution. In a context of global change, aquatic systems are generally subjected to multi-stress conditions due to multiple chemical and/or physical pressures. Among various environmental factors that modulate the ecological effects of toxicants, special attention should be paid to climate change, which is driving an increase in extreme climate events such as sharp temperature rises. In lotic ecosystems, periphyton ensures key ecological functions such as primary production and nutrient cycling. However, although the effects of metals on microbial communities are relatively well known, there is scant data on possible interactions between temperature increase and metal pollution. Here we led a study to evaluate the influence of temperature on the response of phototrophic periphyton to copper (Cu) exposure. Winter communities, collected in a 8 °C river water, were subjected for six weeks to four thermal conditions in microcosms in presence or not of Cu (nominal concentration of 15 μg L"−"1). At the initial river temperature (8 °C), our results confirmed the chronic impact of Cu on periphyton, both in terms of structure (biomass, distribution of algal groups, diatomic composition) and function (photosynthetic efficiency). At higher temperatures (13, 18 and 23 °C), Cu effects were modulated. Indeed, temperature increase reduced Cu effects on algal biomass, algal class proportions, diatom assemblage composition and photosynthetic efficiency. This reduction of Cu effects on periphyton may be related to lower bioaccumulation of Cu and/or to selection of more Cu-tolerant species at higher temperatures. - Highlights: • At in situ temperature, Cu impacted structure and activity of phototrophic biofilms. • Cu effects were reduced with increasing temperature (from +5 °C to +15 °C). • The decrease in Cu effects may be related to lower Cu bioaccumulation in biofilms. • Changes in diatom

  7. Endolithic phototrophs in built and natural stone.

    Science.gov (United States)

    Gaylarde, Christine C; Gaylarde, Peter M; Neilan, Brett A

    2012-08-01

    Lichens, algae and cyanobacteria have been detected growing endolithically in natural rock and in stone buildings in various countries of Australasia, Europe and Latin America. Previously these organisms had mainly been described in natural carbonaceous rocks in aquatic environments, with some reports in siliceous rocks, principally from extremophilic regions. Using various culture and microscopy methods, we have detected endoliths in siliceous stone, both natural and cut, in humid temperate and subtropical climates. Such endolithic growth leads to degradation of the stone structure, not only by mechanical means, but also by metabolites liberated by the cells. Using in vitro culture, transmission, optical and fluorescence microscopy, and confocal laser scanning microscopy, both coccoid and filamentous cyanobacteria and algae, including Cyanidiales, have been identified growing endolithically in the facades of historic buildings built from limestone, sandstone, granite, basalt and soapstone, as well as in some natural rocks. Numerically, the most abundant are small, single-celled, colonial cyanobacteria. These small phototrophs are difficult to detect by standard microscope techniques and some of these species have not been previously reported within stone.

  8. Cyanobacteria in Sulfidic Spring Microbial Mats Can Perform Oxygenic and Anoxygenic Photosynthesis Simultaneously during an Entire Diurnal Period.

    Science.gov (United States)

    Klatt, Judith M; de Beer, Dirk; Häusler, Stefan; Polerecky, Lubos

    2016-01-01

    We used microsensors to study the regulation of anoxygenic and oxygenic photosynthesis (AP and OP, respectively) by light and sulfide in a cyanobacterium dominating microbial mats from cold sulfidic springs. Both photosynthetic modes were performed simultaneously over all H 2 S concentrations (1-2200 μM) and irradiances (4-52 μmol photons m -2 s -1 ) tested. AP increased with H 2 S concentration while the sum of oxygenic and anoxygenic photosynthetic rates was constant at each light intensity. Thus, the total photosynthetically driven electron transport rate was solely controlled by the irradiance level. The partitioning between the rates of these two photosynthetic modes was regulated by both light and H 2 S concentration. The plastoquinone pool (PQ) receives electrons from sulfide:quinone:reductase (SQR) in AP and from photosystem II (PSII) in OP. It is thus the link in the electron transport chain where both pathways intersect, and the compound that controls their partitioning. We fitted our data with a model of the photosynthetic electron transport that includes the kinetics of plastoquinone reduction and oxidation. The model results confirmed that the observed partitioning between photosynthetic modes can be explained by a simple kinetic control based on the affinity of SQR and PSII toward PQ. The SQR enzyme and PSII have similar affinities toward PQ, which explains the concurrent OP and AP over an astonishingly wide range of H 2 S concentrations and irradiances. The elegant kinetic control of activity makes the cyanobacterium successful in the fluctuating spring environment. We discuss how these specific regulation mechanisms may have played a role in ancient H 2 S-rich oceans.

  9. Diversity and distribution of photosynthesis bacteria in the Black Sea

    Czech Academy of Sciences Publication Activity Database

    Koblížek, Michal; Falkowski, P. G.; Kolber, Z. S.

    2006-01-01

    Roč. 53, 17-19 (2006), s. 1934-1944 ISSN 0967-0645 R&D Projects: GA ČR GA204/05/0307; GA MŽP SL/1/6/04 Institutional research plan: CEZ:AV0Z50200510 Keywords : aerobic anoxygenic proto trophs * erythrobacter * roseobacter Subject RIV: EE - Microbiology, Virology Impact factor: 1.358, year: 2006

  10. Feeding by phototrophic red-tide dinoflagellates on the ubiquitous marine diatom Skeletonema costatum.

    Science.gov (United States)

    Du Yoo, Yeong; Jeong, Hae Jin; Kim, Mi Seon; Kang, Nam Seon; Song, Jae Yoon; Shin, Woongghi; Kim, Kwang Young; Lee, Kitack

    2009-01-01

    We investigated feeding by phototrophic red-tide dinoflagellates on the ubiquitous diatom Skeletonema costatum to explore whether dinoflagellates are able to feed on S. costatum, inside the protoplasm of target dinoflagellate cells observed under compound microscope, confocal microscope, epifluorescence microscope, and transmission electron microscope (TEM) after adding living and fluorescently labeled S. costatum (FLSc). To explore effects of dinoflagellate predator size on ingestion rates of S. costatum, we measured ingestion rates of seven dinoflagellates at a single prey concentration. In addition, we measured ingestion rates of the common phototrophic dinoflagellates Prorocentrum micans and Gonyaulax polygramma on S. costatum as a function of prey concentration. We calculated grazing coefficients by combining field data on abundances of P. micans and G. polygramma on co-occurring S. costatum with laboratory data on ingestion rates obtained in the present study. All phototrophic dinoflagellate predators tested (i.e. Akashiwo sanguinea, Amphidinium carterae, Alexandrium catenella, Alexandrium tamarense, Cochlodinium polykrikoides, G. polygramma, Gymnodinium catenatum, Gymnodinium impudicum, Heterocapsa rotundata, Heterocapsa triquetra, Lingulodinium polyedrum, Prorocentrum donghaiense, P. micans, Prorocentrum minimum, Prorocentrum triestinum, and Scrippsiella trochoidea) were able to ingest S. costatum. When mean prey concentrations were 170-260 ng C/ml (i.e. 6,500-10,000 cells/ml), the ingestion rates of G. polygramma, H. rotundata, H. triquetra, L. polyedrum, P. donghaiense, P. micans, and P. triestinum on S. costatum (0.007-0.081 ng C/dinoflagellate/d [0.2-3.0 cells/dinoflagellate/d]) were positively correlated with predator size. With increasing mean prey concentration of ca 1-3,440 ng C/ml (40-132,200 cells/ml), the ingestion rates of P. micans and G. polygramma on S. costatum continuously increased. At the given prey concentrations, the maximum ingestion

  11. Synthesis of UDP-apiose in Bacteria: The marine phototroph Geminicoccus roseus and the plant pathogen Xanthomonas pisi.

    Directory of Open Access Journals (Sweden)

    James Amor Smith

    Full Text Available The branched-chain sugar apiose was widely assumed to be synthesized only by plant species. In plants, apiose-containing polysaccharides are found in vascularized plant cell walls as the pectic polymers rhamnogalacturonan II and apiogalacturonan. Apiosylated secondary metabolites are also common in many plant species including ancestral avascular bryophytes and green algae. Apiosyl-residues have not been documented in bacteria. In a screen for new bacterial glycan structures, we detected small amounts of apiose in methanolic extracts of the aerobic phototroph Geminicoccus roseus and the pathogenic soil-dwelling bacteria Xanthomonas pisi. Apiose was also present in the cell pellet of X. pisi. Examination of these bacterial genomes uncovered genes with relatively low protein homology to plant UDP-apiose/UDP-xylose synthase (UAS. Phylogenetic analysis revealed that these bacterial UAS-like homologs belong in a clade distinct to UAS and separated from other nucleotide sugar biosynthetic enzymes. Recombinant expression of three bacterial UAS-like proteins demonstrates that they actively convert UDP-glucuronic acid to UDP-apiose and UDP-xylose. Both UDP-apiose and UDP-xylose were detectable in cell cultures of G. roseus and X. pisi. We could not, however, definitively identify the apiosides made by these bacteria, but the detection of apiosides coupled with the in vivo transcription of bUAS and production of UDP-apiose clearly demonstrate that these microbes have evolved the ability to incorporate apiose into glycans during their lifecycles. While this is the first report to describe enzymes for the formation of activated apiose in bacteria, the advantage of synthesizing apiose-containing glycans in bacteria remains unknown. The characteristics of bUAS and its products are discussed.

  12. Metatranscriptomic analysis of a high-sulfide aquatic spring reveals insights into sulfur cycling and unexpected aerobic metabolism

    Directory of Open Access Journals (Sweden)

    Anne M. Spain

    2015-09-01

    Full Text Available Zodletone spring is a sulfide-rich spring in southwestern Oklahoma characterized by shallow, microoxic, light-exposed spring water overlaying anoxic sediments. Previously, culture-independent 16S rRNA gene based diversity surveys have revealed that Zodletone spring source sediments harbor a highly diverse microbial community, with multiple lineages putatively involved in various sulfur-cycling processes. Here, we conducted a metatranscriptomic survey of microbial populations in Zodletone spring source sediments to characterize the relative prevalence and importance of putative phototrophic, chemolithotrophic, and heterotrophic microorganisms in the sulfur cycle, the identity of lineages actively involved in various sulfur cycling processes, and the interaction between sulfur cycling and other geochemical processes at the spring source. Sediment samples at the spring’s source were taken at three different times within a 24-h period for geochemical analyses and RNA sequencing. In depth mining of datasets for sulfur cycling transcripts revealed major sulfur cycling pathways and taxa involved, including an unexpected potential role of Actinobacteria in sulfide oxidation and thiosulfate transformation. Surprisingly, transcripts coding for the cyanobacterial Photosystem II D1 protein, methane monooxygenase, and terminal cytochrome oxidases were encountered, indicating that genes for oxygen production and aerobic modes of metabolism are actively being transcribed, despite below-detectable levels (<1 µM of oxygen in source sediment. Results highlight transcripts involved in sulfur, methane, and oxygen cycles, propose that oxygenic photosynthesis could support aerobic methane and sulfide oxidation in anoxic sediments exposed to sunlight, and provide a viewpoint of microbial metabolic lifestyles under conditions similar to those seen during late Archaean and Proterozoic eons.

  13. Settling properties of aerobic granular sludge (AGS) and aerobic granular sludge molasses (AGSM)

    Science.gov (United States)

    Mat Saad, Azlina; Aini Dahalan, Farrah; Ibrahim, Naimah; Yasina Yusuf, Sara; Aqlima Ahmad, Siti; Khalil, Khalilah Abdul

    2018-03-01

    Aerobic granulation technology is applied to treat domestic and industrial wastewater. The Aerobic granular sludge (AGS) cultivated has strong properties that appears to be denser and compact in physiological structure compared to the conventional activated sludge. It offers rapid settling for solid:liquid separation in wastewater treatment. Aerobic granules were developed using sequencing batch reactor (SBR) with intermittent aerobic - anaerobic mode with 8 cycles in 24 hr. This study examined the settling velocity performance of cultivated aerobic granular sludge (AGS) and aerobic granular sludge molasses (AGSM). The elemental composition in both AGS and AGSM were determined using X-ray fluorescence (XRF). The results showed that AGSM has higher settling velocity 30.5 m/h compared to AGS.

  14. Examining physiotherapist use of structured aerobic exercise testing to decrease barriers to aerobic exercise.

    Science.gov (United States)

    Foster B Sc, Evan; Fraser, Julia E; Inness PhD, Elizabeth L; Munce, Sarah; Biasin, Louis; Poon, Vivien; Bayley, Mark

    2018-04-03

    To determine the frequency of physiotherapist-administered aerobic exercise testing/training, the proportion of physiotherapists who administer this testing/training, and the barriers that currently exist across different practice environments. A secondary objective is to identify the learning needs of physiotherapists for the development of an education curriculum in aerobic exercise testing and training with electrocardiograph (ECG) administration and interpretation. National, cross-sectional survey. Registered physiotherapists practicing in Canada. Out of 137 participants, most (75%) physiotherapists prescribed aerobic exercise on a regular basis (weekly); however, 65% had never conducted an aerobic exercise test. There were no significant differences in frequency of aerobic exercise testing across different practice environments or across years of physiotherapy experience. Physiotherapists perceived the main barriers to aerobic exercise testing as being a lack of equipment/space (78%), time (65%), and knowledge (56%). Although most (82%) were uncomfortable administering 12-lead ECG-monitored aerobic exercise tests, 60% stated they would be interested in learning more about ECG interpretation. This study found that physiotherapists are regularly implementing aerobic exercise. This exercise was infrequently guided by formal aerobic exercise testing, which could increase access to safe and effective exercise within the optimal aerobic training zone. As well, this could facilitate training in patients with cardiovascular diagnoses that require additional testing for medical clearance. Increased ECG training and access to equipment for physiotherapists may augment pre-screening aerobic exercise testing. This training should include learning the key arrhythmias for aerobic exercise test termination as defined by the American College of Sports Medicine.

  15. Isolation and Identification of Phototrophic Microorganisms from Rudkhan Castle as a Biodeteriorating Agent

    Directory of Open Access Journals (Sweden)

    Parisa Mohammadi

    2016-09-01

    Full Text Available Introduction: Phototrophic microorganisms are the first residents of different surfaces of ancient buildings’ walls. These organisms can expand to provide the colonization of other microorganisms and to form microbial biofilms. During biofilm growth, acids and metabolites production bore the substratum and cause surfaces damages. Rudkan Castle, the historic monument located in Gilan province, an area with a humid climate has an appropriate surfaces to grow these microorganisms. Materials and methods: In this study, morphological identification of algae and cyanobacteria which was isolated from different areas of the brick walls of Castle has been investigated. Samples were taken from 24 different areas of Castle walls and were aseptically cultured into Blue Green Medium (BGM and Bolds Basal Medium (BBM, and colonies were observed using light microscopy. Results: The dominant organisms which were isolated and identified, were Cladophora, Trentepohlia, Klebsormidium, Trebouxia, Pleurastrum, Chlorococcum as chlorophyta order and Scytonema, Tolypothrix, Leptolyngbya, Plectolyngbya, Phormidium, Gloeocapsa, Microcoleus, Nostoc as a cyanobacteria order. Discussion and conclusion: As expected, diversity of a large number of cyanobacteria and algae phototrophs was isolated. Diversity of organisms on the surface of monuments depends on many factors, including the weather condition such as moisture, the amount of radiation absorbed by the surface, temperature of area, the materials used in the monuments, the biological acceptance of surface and presence of variety of organisms in the soil surface and the air on. Study of destructive factors is the first step toward the protection and restoration of ancient monuments.

  16. Aerobic transformation of cadmium through metal sulfide biosynthesis in photosynthetic microorganisms.

    Science.gov (United States)

    Edwards, Chad D; Beatty, Joseph C; Loiselle, Jacqueline B R; Vlassov, Katya A; Lefebvre, Daniel D

    2013-07-15

    Cadmium is a non-essential metal that is toxic because of its interference with essential metals such as iron, calcium and zinc causing numerous detrimental metabolic and cellular effects. The amount of this metal in the environment has increased dramatically since the advent of the industrial age as a result of mining activities, the use of fertilizers and sewage sludge in farming, and discharges from manufacturing activities. The metal bioremediation utility of phototrophic microbes has been demonstrated through their ability to detoxify Hg(II) into HgS under aerobic conditions. Metal sulfides are generally very insoluble and therefore, biologically unavailable. When Cd(II) was exposed to cells it was bioconverted into CdS by the green alga Chlamydomonas reinhardtii, the red alga Cyanidioschyzon merolae, and the cyanobacterium, Synechoccocus leopoliensis. Supplementation of the two eukaryotic algae with extra sulfate, but not sulfite or cysteine, increased their cadmium tolerances as well as their abilities to produce CdS, indicating an involvement of sulfate assimilation in the detoxification process. However, the combined activities of extracted serine acetyl-transferase (SAT) and O-acetylserine(thiol)lyase (OASTL) used to monitor sulfate assimilation, was not significantly elevated during cell treatments that favored sulfide biosynthesis. It is possible that the prolonged incubation of the experiments occurring over two days could have compensated for the low rates of sulfate assimilation. This was also the case for S. leopoliensis where sulfite and cysteine as well as sulfate supplementation enhanced CdS synthesis. In general, conditions that increased cadmium sulfide production also resulted in elevated cysteine desulfhydrase activities, strongly suggesting that cysteine is the direct source of sulfur for CdS synthesis. Cadmium(II) tolerance and CdS formation were significantly enhanced by sulfate supplementation, thus indicating that algae and cyanobacteria

  17. Genome Sequences and Photosynthesis Gene Cluster Composition of a Freshwater Aerobic Anoxygenic Phototroph, Sandarakinorhabdus asp. Strain AAP62, Isolated from the Shahu Lake in Ningxia, China

    Czech Academy of Sciences Publication Activity Database

    Zeng, Yonghui; Feng, F.; Liu, Y.; Koblížek, Michal

    2013-01-01

    Roč. 1, č. 1 (2013) ISSN 2169-8287 R&D Projects: GA ČR GAP501/10/0221; GA MŠk(CZ) ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : Gene cluster * Sandarakinorhabdus Subject RIV: EE - Microbiology, Virology http://genomea. asm .org/content/1/1/e00034-13.full

  18. Functional structure of the bromeliad tank microbiome is strongly shaped by local geochemical conditions.

    Science.gov (United States)

    Louca, Stilianos; Jacques, Saulo M S; Pires, Aliny P F; Leal, Juliana S; González, Angélica L; Doebeli, Michael; Farjalla, Vinicius F

    2017-08-01

    Phytotelmata in tank-forming Bromeliaceae plants are regarded as potential miniature models for aquatic ecology, but detailed investigations of their microbial communities are rare. Hence, the biogeochemistry in bromeliad tanks remains poorly understood. Here we investigate the structure of bacterial and archaeal communities inhabiting the detritus within the tanks of two bromeliad species, Aechmea nudicaulis and Neoregelia cruenta, from a Brazilian sand dune forest. We used metagenomic sequencing for functional community profiling and 16S sequencing for taxonomic profiling. We estimated the correlation between functional groups and various environmental variables, and compared communities between bromeliad species. In all bromeliads, microbial communities spanned a metabolic network adapted to oxygen-limited conditions, including all denitrification steps, ammonification, sulfate respiration, methanogenesis, reductive acetogenesis and anoxygenic phototrophy. Overall, CO2 reducers dominated in abundance over sulfate reducers, and anoxygenic phototrophs largely outnumbered oxygenic photoautotrophs. Functional community structure correlated strongly with environmental variables, between and within a single bromeliad species. Methanogens and reductive acetogens correlated with detrital volume and canopy coverage, and exhibited higher relative abundances in N. cruenta. A comparison of bromeliads to freshwater lake sediments and soil from around the world, revealed stark differences in terms of taxonomic as well as functional microbial community structure. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  19. Nutrient Acquisition and the Metabolic Potential of Photoferrotrophic Chlorobi

    Directory of Open Access Journals (Sweden)

    Katharine J. Thompson

    2017-07-01

    Full Text Available Anoxygenic photosynthesis evolved prior to oxygenic photosynthesis and harnessed energy from sunlight to support biomass production on the early Earth. Models that consider the availability of electron donors predict that anoxygenic photosynthesis using Fe(II, known as photoferrotrophy, would have supported most global primary production before the proliferation of oxygenic phototrophs at approximately 2.3 billion years ago. These photoferrotrophs have also been implicated in the deposition of banded iron formations, the world’s largest sedimentary iron ore deposits that formed mostly in late Archean and early Proterozoic Eons. In this work we present new data and analyses that illuminate the metabolic capacity of photoferrotrophy in the phylum Chlorobi. Our laboratory growth experiments and biochemical analyses demonstrate that photoferrotrophic Chlorobi are capable of assimilatory sulfate reduction and nitrogen fixation under sulfate and nitrogen limiting conditions, respectively. Furthermore, the evolutionary histories of key enzymes in both sulfur (CysH and CysD and nitrogen fixation (NifDKH pathways are convoluted; protein phylogenies, however, suggest that early Chlorobi could have had the capacity to assimilate sulfur and fix nitrogen. We argue, then, that the capacity for photoferrotrophic Chlorobi to acquire these key nutrients enabled them to support primary production and underpin global biogeochemical cycles in the Precambrian.

  20. Aerobic exercise (image)

    Science.gov (United States)

    Aerobic exercise gets the heart working to pump blood through the heart more quickly and with more ... must be oxygenated more quickly, which quickens respiration. Aerobic exercise strengthens the heart and boosts healthy cholesterol ...

  1. Regulation of electron transfer processes affects phototrophic mat structure and activity

    Science.gov (United States)

    Ha, Phuc T.; Renslow, Ryan S.; Atci, Erhan; Reardon, Patrick N.; Lindemann, Stephen R.; Fredrickson, James K.; Call, Douglas R.; Beyenal, Haluk

    2015-01-01

    Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located near Oroville (Washington, USA). We operated two reactors: graphite electrodes were polarized at potentials of -700 mVAg/AgCl [cathodic (CAT) mat system] and +300 mVAg/AgCl [anodic (AN) mat system] and the electron transfer rates between the electrode and mat were monitored. We observed a diel cycle of electron transfer rates for both AN and CAT mat systems. Interestingly, the CAT mats generated the highest reducing current at the same time points that the AN mats showed the highest oxidizing current. To characterize the physicochemical factors influencing electron transfer processes, we measured depth profiles of dissolved oxygen (DO) and sulfide in the mats using microelectrodes. We further demonstrated that the mat-to-electrode and electrode-to-mat electron transfer rates were light- and temperature-dependent. Using nuclear magnetic resonance (NMR) imaging, we determined that the electrode potential regulated the diffusivity and porosity of the microbial mats. Both porosity and diffusivity were higher in the CAT mats than in the AN mats. We also used NMR spectroscopy for high-resolution quantitative metabolite analysis and found that the CAT mats had significantly higher concentrations of osmoprotectants such as betaine and trehalose. Subsequently, we performed amplicon sequencing across the V4 region of the 16S rRNA gene of incubated mats to understand the impact of electrode potential on microbial community structure. These data suggested that variation in the

  2. Regulation of electron transfer processes affects phototrophic mat structure and activity

    Directory of Open Access Journals (Sweden)

    Haluk eBeyenal

    2015-09-01

    Full Text Available Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located near Oroville (Washington, USA. We operated two reactors: graphite electrodes were polarized at potentials of -700 mVAg/AgCl (cathodic mat system and +300 mVAg/AgCl (anodic mat system and the electron transfer rates between the electrode and mat were monitored. We observed a diel cycle of electron transfer rates for both anodic and cathodic mat systems. Interestingly, the cathodic mats generated the highest reducing current at the same time points that the anodic mats showed the highest oxidizing current. To characterize the physicochemical factors influencing electron transfer processes, we measured depth profiles of dissolved oxygen and sulfide in the mats using microelectrodes. We further demonstrated that the mat-to-electrode and electrode-to-mat electron transfer rates were light- and temperature-dependent. Using nuclear magnetic resonance (NMR imaging, we determined that the electrode potential regulated the diffusivity and porosity of the microbial mats. Both porosity and diffusivity were higher in the cathodic mats than in the anodic mats. We also used NMR spectroscopy for high-resolution quantitative metabolite analysis and found that the cathodic mats had significantly higher concentrations of osmoprotectants such as betaine and trehalose. Subsequently, we performed amplicon sequencing across the V4 region of the 16S rRNA gene of incubated mats to understand the impact of electrode potential on microbial community structure. These data suggested that

  3. Regulation of electron transfer processes affects phototrophic mat structure and activity.

    Science.gov (United States)

    Ha, Phuc T; Renslow, Ryan S; Atci, Erhan; Reardon, Patrick N; Lindemann, Stephen R; Fredrickson, James K; Call, Douglas R; Beyenal, Haluk

    2015-01-01

    Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located near Oroville (Washington, USA). We operated two reactors: graphite electrodes were polarized at potentials of -700 mVAg/AgCl [cathodic (CAT) mat system] and +300 mVAg/AgCl [anodic (AN) mat system] and the electron transfer rates between the electrode and mat were monitored. We observed a diel cycle of electron transfer rates for both AN and CAT mat systems. Interestingly, the CAT mats generated the highest reducing current at the same time points that the AN mats showed the highest oxidizing current. To characterize the physicochemical factors influencing electron transfer processes, we measured depth profiles of dissolved oxygen (DO) and sulfide in the mats using microelectrodes. We further demonstrated that the mat-to-electrode and electrode-to-mat electron transfer rates were light- and temperature-dependent. Using nuclear magnetic resonance (NMR) imaging, we determined that the electrode potential regulated the diffusivity and porosity of the microbial mats. Both porosity and diffusivity were higher in the CAT mats than in the AN mats. We also used NMR spectroscopy for high-resolution quantitative metabolite analysis and found that the CAT mats had significantly higher concentrations of osmoprotectants such as betaine and trehalose. Subsequently, we performed amplicon sequencing across the V4 region of the 16S rRNA gene of incubated mats to understand the impact of electrode potential on microbial community structure. These data suggested that variation in the

  4. Ecological divergence of a novel group of Chloroflexus strains along a geothermal gradient.

    Science.gov (United States)

    Weltzer, Michael L; Miller, Scott R

    2013-02-01

    Environmental gradients are expected to promote the diversification and coexistence of ecological specialists adapted to local conditions. Consistent with this view, genera of phototrophic microorganisms in alkaline geothermal systems generally appear to consist of anciently divergent populations which have specialized on different temperature habitats. At White Creek (Lower Geyser Basin, Yellowstone National Park), however, a novel, 16S rRNA-defined lineage of the filamentous anoxygenic phototroph Chloroflexus (OTU 10, phylum Chloroflexi) occupies a much wider thermal niche than other 16S rRNA-defined groups of phototrophic bacteria. This suggests that Chloroflexus OTU 10 is either an ecological generalist or, alternatively, a group of cryptic thermal specialists which have recently diverged. To distinguish between these alternatives, we first isolated laboratory strains of Chloroflexus OTU 10 from along the White Creek temperature gradient. These strains are identical for partial gene sequences encoding the 16S rRNA and malonyl coenzyme A (CoA) reductase. However, strains isolated from upstream and downstream samples could be distinguished based on sequence variation at pcs, which encodes the propionyl-CoA synthase of the 3-hydroxypropionate pathway of carbon fixation used by the genus Chloroflexus. We next demonstrated that strains have diverged in temperature range for growth. Specifically, we obtained evidence for a positive correlation between thermal niche breadth and temperature optimum, with strains isolated from lower temperatures exhibiting greater thermal specialization than the most thermotolerant strain. The study has implications for our understanding of both the process of niche diversification of microorganisms and how diversity is organized in these hot spring communities.

  5. Development of a laboratory model of a phototroph-heterotroph mixed-species biofilm at the stone/air interface

    Directory of Open Access Journals (Sweden)

    Federica eVilla

    2015-11-01

    Full Text Available Recent scientific investigations have shed light on the ecological importance and physiological complexity of subaerial biofilms (SABs inhabiting lithic surfaces. In the field of sustainable cultural heritage (CH preservation, mechanistic approaches aimed at investigation of the spatiotemporal patterns of interactions between the biofilm, the stone, and the atmosphere are of outstanding importance. However, these interactions have proven difficult to explore with field experiments due to the inaccessibility of samples, the complexity of the ecosystem under investigation and the temporal resolution of the experiments.To overcome these limitations, we aimed at developing a unifying methodology to reproduce a fast-growing, phototroph-heterotroph mixed species biofilm at the stone/air interface. Our experiments underscore the ability of the dual-species SAB model to capture functional traits characteristic of biofilms inhabiting lithic substrate such as: i microcolonies of aggregated bacteria; ii network like structure following surface topography; iii cooperation between phototrophs and heterotrophs and cross feeding processes; iv ability to change the chemical parameters that characterize the microhabitats; v survival under desiccation and vi biocide tolerance. With its advantages in control, replication, range of different experimental scenarios and matches with the real ecosystem, the developed model system is a powerful tool to advance our mechanistic understanding of the stone-biofilm-atmosphere interplay in different environments.

  6. Photosynthetic microbial mats today, on early Earth, (and on early Mars?)

    Science.gov (United States)

    Des Marais, D. J.

    2008-05-01

    Marine hypersaline cyanobacterial mats offer insights about their ancient ancestors, whose fossil record is 3.43 billion years old. Studies of mat microbiota have greatly expanded the known diversity of ancient microbial lineages. Their evolution was shaped by mat microenvironments, which can differ substantially from their surroundings. Oxygenic photosynthesis perhaps developed in microbial mats and probably triggered a major evolutionary transformation and diversification of the early biosphere. Gross primary production rates in cyanobacterial mats can rival the most productive ecosystems known. Sunlight changes in intensity and spectral composition as it penetrates mats, and counteracting gradients of O2 and sulfide shape the chemical microenvironment. A combination of benefits and hazards of light, O2 and sulfide promotes the allocation of the various essential mat processes between light and dark periods and to various depths in the mat. Close inspection has revealed surprises, for example: anoxygenic phototrophs inside cyanobacterial sheaths, record- high sulfate reduction rates in O2-saturated conditions, and high H2 fluxes into overlying waters. Diverse organic biomarker compounds have been documented that are amenable to long-term preservation. Such coordinated observations of populations, processes and products are making fundamental questions in ecology accessible. Cyanobacterial mats have robust fossil records in part because they populated stable continental platforms and margins, contributing to sediments having high preservation potential. Proterozoic cyanobacterial fossils and organic biomarkers are well documented. The 3.43 Ga Strelley Pool cherts, W. Australia, reveal diverse stromatolites that populated a partially restricted, low-energy shallow hypersaline basin. Molecular studies of extant bacteria hint that early chlorophyll-utilizing photosynthesizers required geochemical sources of reductants. Did these anoxygenic phototrophs once sustain an

  7. Aerobic Anoxygenic Photosynthesis Is Commonly Present within the Genus Limnohabitans

    Czech Academy of Sciences Publication Activity Database

    Kasalický, Vojtěch; Zeng, Yonghui; Piwosz, Kasia; Šimek, Karel; Kratochvílová, Hana; Koblížek, Michal

    2018-01-01

    Roč. 84, č. 1 (2018), č. článku e02116-17. ISSN 0099-2240 R&D Projects: GA MŠk(CZ) EE2.3.30.0032; GA ČR(CZ) GA13-00243S; GA ČR GA15-12197S; GA MŠk(CZ) LO1416 Institutional support: RVO:60077344 ; RVO:61388971 Keywords : fish * IR microscopy * Limnohabitans * bacteriochlorophyll * bchY Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology; Microbiology (MBU-M) Impact factor: 3.807, year: 2016

  8. Novel thiols of prokaryotes.

    Science.gov (United States)

    Fahey, R C

    2001-01-01

    Glutathione metabolism is associated with oxygenic cyanobacteria and the oxygen-utilizing purple bacteria, but is absent in many other prokaryotes. This review focuses on novel thiols found in those bacteria lacking glutathione. Included are glutathione amide and its perthiol, produced by phototrophic purple sulfur bacteria and apparently involved in their sulfide metabolism. Among archaebacteria, coenzyme M (2-mercaptoethanesulfonic acid) and coenzyme B (7-mercaptoheptanoylthreonine phosphate) play central roles in the anaerobic production of CH4 and associated energy conversion by methanogens, whereas the major thiol in the aerobic phototrophic halobacteria is gamma-glutamylcysteine. The highly aerobic actinomycetes produce mycothiol, a conjugate of N-acetylcysteine with a pseudodisaccharide of glucosamine and myo-inositol, AcCys-GlcNalpha(1 --> 1)Ins, which appears to play an antioxidant role similar to glutathione. Ergothioneine, also produced by actinomycetes, remains a mystery despite many years of study. Available data on the biosynthesis and metabolism of these and other novel thiols is summarized and key areas for additional study are identified.

  9. Molecular evolution of the nif gene cluster carrying nifI1 and nifI2 genes in the Gram-positive phototrophic bacterium Heliobacterium chlorum.

    Science.gov (United States)

    Enkh-Amgalan, Jigjiddorj; Kawasaki, Hiroko; Seki, Tatsuji

    2006-01-01

    A major nif cluster was detected in the strictly anaerobic, Gram-positive phototrophic bacterium Heliobacterium chlorum. The cluster consisted of 11 genes arranged within a 10 kb region in the order nifI1, nifI2, nifH, nifD, nifK, nifE, nifN, nifX, fdx, nifB and nifV. The phylogenetic position of Hbt. chlorum was the same in the NifH, NifD, NifK, NifE and NifN trees; Hbt. chlorum formed a cluster with Desulfitobacterium hafniense, the closest neighbour of heliobacteria based on the 16S rRNA phylogeny, and two species of the genus Geobacter belonging to the Deltaproteobacteria. Two nifI genes, known to occur in the nif clusters of methanogenic archaea between nifH and nifD, were found upstream of the nifH gene of Hbt. chlorum. The organization of the nif operon and the phylogeny of individual and concatenated gene products showed that the Hbt. chlorum nif operon carrying nifI genes upstream of the nifH gene was an intermediate between the nif operon with nifI downstream of nifH (group II and III of the nitrogenase classification) and the nif operon lacking nifI (group I). Thus, the phylogenetic position of Hbt. chlorum nitrogenase may reflect an evolutionary stage of a divergence of the two nitrogenase groups, with group I consisting of the aerobic diazotrophs and group II consisting of strictly anaerobic prokaryotes.

  10. Management of aerobic vaginitis.

    Science.gov (United States)

    Tempera, Gianna; Furneri, Pio Maria

    2010-01-01

    Aerobic vaginitis is a new nonclassifiable pathology that is neither specific vaginitis nor bacterial vaginosis. The diversity of this microbiological peculiarity could also explain several therapeutic failures when patients were treated for infections identified as bacterial vaginosis. The diagnosis 'aerobic vaginitis' is essentially based on microscopic examinations using a phase-contrast microscope (at ×400 magnification). The therapeutic choice for 'aerobic vaginitis' should take into consideration an antibiotic characterized by an intrinsic activity against the majority of bacteria of fecal origin, bactericidal effect and poor/absent interference with the vaginal microbiota. Regarding the therapy for aerobic vaginitis when antimicrobial agents are prescribed, not only the antimicrobial spectrum but also the presumed ecological disturbance on the anaerobic and aerobic vaginal and rectal microbiota should be taken into a consideration. Because of their very low impact on the vaginal microbiota, kanamycin or quinolones are to be considered a good choice for therapy. Copyright © 2010 S. Karger AG, Basel.

  11. Effect of copper and lead on two consortia of phototrophic microorganisms and their capacity to sequester metals

    Energy Technology Data Exchange (ETDEWEB)

    Burgos, A. [Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Edifici C, Campus de UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona (Spain); Departamento de Recursos Hidrobiológicos, Universidad de Nariño, Pasto (N) (Colombia); Maldonado, J. [Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Edifici C, Campus de UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona (Spain); De los Rios, A. [Museo Nacional de Ciencias Naturales(CSIC), Serrano 115 dpdo, 28006 Madrid (Spain); Solé, A. [Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Edifici C, Campus de UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona (Spain); Esteve, I., E-mail: isabel.esteve@uab.cat [Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Edifici C, Campus de UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona (Spain); Departamento de Recursos Hidrobiológicos, Universidad de Nariño, Pasto (N) (Colombia); Museo Nacional de Ciencias Naturales(CSIC), Serrano 115 dpdo, 28006 Madrid (Spain)

    2013-09-15

    Highlights: •We studied the tolerance-resistance of phototrophic microorganisms to copper and lead. •We determined the capacity of consortia of microorganisms to sequester copper and lead. •CLSM-λscan is a technique for evaluating in vivo effect of metals on microorganisms. •SEM-EDX and TEM-EDX determined the capacity of microorganisms to sequester metals. -- Abstract: The roles of consortia of phototrophic microorganisms have been investigated in this paper to determine their potential role to tolerate or resist metals and to capture them from polluted cultures. With this purpose, two consortia of microorganisms: on one hand, Geitlerinema sp. DE2011 (Ge) and Scenedesmus sp. DE2009 (Sc) (both identified in this paper by molecular biology methods) isolated from Ebro Delta microbial mats, and on the other, Spirulina sp. PCC 6313 (Sp) and Chroococcus sp. PCC 9106 (Ch), from Pasteur culture collection were polluted with copper and lead. In order to analyze the ability of these consortia to tolerate and capture metals, copper and lead were selected, because both have been detected in Ebro Delta microbial mats. The tolerance-resistance to copper and lead for both consortia was determined in vivo and at cellular level by Confocal Laser Scanning Microscopy (CLSM-λscan function). The results obtained demonstrate that both consortia are highly tolerant-resistant to lead and that the limits between the copper concentration having cytotoxic effect and that having an essential effect are very close in these microorganisms. The capacity of both consortia to capture extra- and intracellular copper and lead was determined by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) respectively, coupled to an Energy Dispersive X-ray detector (EDX). The results showed that all the microorganisms assayed were able to capture copper extracellularly in the extrapolymeric substances, and lead extra- and intracellularly in polyphosphate inclusions. Moreover

  12. Effect of copper and lead on two consortia of phototrophic microorganisms and their capacity to sequester metals

    International Nuclear Information System (INIS)

    Burgos, A.; Maldonado, J.; De los Rios, A.; Solé, A.; Esteve, I.

    2013-01-01

    Highlights: •We studied the tolerance-resistance of phototrophic microorganisms to copper and lead. •We determined the capacity of consortia of microorganisms to sequester copper and lead. •CLSM-λscan is a technique for evaluating in vivo effect of metals on microorganisms. •SEM-EDX and TEM-EDX determined the capacity of microorganisms to sequester metals. -- Abstract: The roles of consortia of phototrophic microorganisms have been investigated in this paper to determine their potential role to tolerate or resist metals and to capture them from polluted cultures. With this purpose, two consortia of microorganisms: on one hand, Geitlerinema sp. DE2011 (Ge) and Scenedesmus sp. DE2009 (Sc) (both identified in this paper by molecular biology methods) isolated from Ebro Delta microbial mats, and on the other, Spirulina sp. PCC 6313 (Sp) and Chroococcus sp. PCC 9106 (Ch), from Pasteur culture collection were polluted with copper and lead. In order to analyze the ability of these consortia to tolerate and capture metals, copper and lead were selected, because both have been detected in Ebro Delta microbial mats. The tolerance-resistance to copper and lead for both consortia was determined in vivo and at cellular level by Confocal Laser Scanning Microscopy (CLSM-λscan function). The results obtained demonstrate that both consortia are highly tolerant-resistant to lead and that the limits between the copper concentration having cytotoxic effect and that having an essential effect are very close in these microorganisms. The capacity of both consortia to capture extra- and intracellular copper and lead was determined by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) respectively, coupled to an Energy Dispersive X-ray detector (EDX). The results showed that all the microorganisms assayed were able to capture copper extracellularly in the extrapolymeric substances, and lead extra- and intracellularly in polyphosphate inclusions. Moreover

  13. Oxygen, climate and the chemical evolution of a 1400 million year old tropical marine setting

    DEFF Research Database (Denmark)

    Wang, Xiaomei; Zhang, Shuichang; Wang, Huajian

    2017-01-01

    by oxygenated bottom waters. The transition to unit 3 reflects an increase in primary productivity, and the development of a more biologically active OMZ, that supported anoxygenic phototrophic bacteria. Still, in this unit, the bottom waters remained oxygenated. The overlying unit 2 represents the transition...... for the iron. However, the low organic carbon contents, low hydrogen index (HI) values, and the oxidized nature of the reactive iron pool indicate deposition in oxygenated bottom waters. We interpret unit 4 to represent a low-productivity ferruginous oxygen-minimum zone (OMZ) environment, underlain......The Xiamaling Formation is an exceptionally well-preserved sedimentary succession deposited on a marine passive margin about 1400 million years ago. We used a multi-proxy approach, including iron speciation, trace metal dynamics, and organic geochemistry, to explore the evolution of ocean chemistry...

  14. Aerobic conditioning for team sport athletes.

    Science.gov (United States)

    Stone, Nicholas M; Kilding, Andrew E

    2009-01-01

    Team sport athletes require a high level of aerobic fitness in order to generate and maintain power output during repeated high-intensity efforts and to recover. Research to date suggests that these components can be increased by regularly performing aerobic conditioning. Traditional aerobic conditioning, with minimal changes of direction and no skill component, has been demonstrated to effectively increase aerobic function within a 4- to 10-week period in team sport players. More importantly, traditional aerobic conditioning methods have been shown to increase team sport performance substantially. Many team sports require the upkeep of both aerobic fitness and sport-specific skills during a lengthy competitive season. Classic team sport trainings have been shown to evoke marginal increases/decreases in aerobic fitness. In recent years, aerobic conditioning methods have been designed to allow adequate intensities to be achieved to induce improvements in aerobic fitness whilst incorporating movement-specific and skill-specific tasks, e.g. small-sided games and dribbling circuits. Such 'sport-specific' conditioning methods have been demonstrated to promote increases in aerobic fitness, though careful consideration of player skill levels, current fitness, player numbers, field dimensions, game rules and availability of player encouragement is required. Whilst different conditioning methods appear equivalent in their ability to improve fitness, whether sport-specific conditioning is superior to other methods at improving actual game performance statistics requires further research.

  15. A Mesoproterozoic iron formation

    Science.gov (United States)

    Canfield, Donald E.; Zhang, Shuichang; Wang, Huajian; Wang, Xiaomei; Zhao, Wenzhi; Su, Jin; Bjerrum, Christian J.; Haxen, Emma R.; Hammarlund, Emma U.

    2018-04-01

    We describe a 1,400 million-year old (Ma) iron formation (IF) from the Xiamaling Formation of the North China Craton. We estimate this IF to have contained at least 520 gigatons of authigenic Fe, comparable in size to many IFs of the Paleoproterozoic Era (2,500–1,600 Ma). Therefore, substantial IFs formed in the time window between 1,800 and 800 Ma, where they are generally believed to have been absent. The Xiamaling IF is of exceptionally low thermal maturity, allowing the preservation of organic biomarkers and an unprecedented view of iron-cycle dynamics during IF emplacement. We identify tetramethyl aryl isoprenoid (TMAI) biomarkers linked to anoxygenic photosynthetic bacteria and thus phototrophic Fe oxidation. Although we cannot rule out other pathways of Fe oxidation, iron and organic matter likely deposited to the sediment in a ratio similar to that expected for anoxygenic photosynthesis. Fe reduction was likely a dominant and efficient pathway of organic matter mineralization, as indicated by organic matter maturation by Rock Eval pyrolysis combined with carbon isotope analyses: Indeed, Fe reduction was seemingly as efficient as oxic respiration. Overall, this Mesoproterozoic-aged IF shows many similarities to Archean-aged (>2,500 Ma) banded IFs (BIFs), but with an exceptional state of preservation, allowing an unprecedented exploration of Fe-cycle dynamics in IF deposition.

  16. Short-term water-based aerobic training promotes improvements in aerobic conditioning parameters of mature women.

    Science.gov (United States)

    Costa, Rochelle Rocha; Reichert, Thais; Coconcelli, Leandro; Simmer, Nicole Monticelli; Bagatini, Natália Carvalho; Buttelli, Adriana Cristine Koch; Bracht, Cláudia Gomes; Stein, Ricardo; Kruel, Luiz Fernando Martins

    2017-08-01

    Aging is accompanied by a decrease in aerobic capacity. Therefore, physical training has been recommended to soften the effects of advancement age. The aim of this study was to assess the effects of a short-term water-based aerobic training on resting heart rate (HR rest ), heart rate corresponding to anaerobic threshold (HR AT ), peak heart rate (HR peak ), percentage value of HR AT in relation to HR peak and test duration (TD) of mature women. Twenty-two women (65.91 ± 4.83 years) were submitted to a five-week water-based interval aerobic training. Aerobic capacity parameters were evaluated through an aquatic incremental test. After training, there was an increase in TD (16%) and HR AT percentage in relation to HR peak (4.68%), and a reduction of HR rest (9%). It is concluded that a water-based aerobic interval training prescribed through HR AT of only five weeks is able to promote improvements in aerobic capacity of mature women. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Community Structure and Function of High-temperature Chlorophototrophic Microbial Mats Inhabiting Diverse Geothermal Environments

    Directory of Open Access Journals (Sweden)

    William P. Inskeep

    2013-06-01

    Full Text Available Six phototrophic microbial mat communities from different geothermal springs (YNP were studied using metagenome sequencing and geochemical analyses. The primary goals of this work were to determine differences in community composition of high-temperature phototrophic mats distributed across the Yellowstone geothermal ecosystem, and to identify metabolic attributes of predominant organisms present in these communities that may correlate with environmental attributes important in niche differentiation. Random shotgun metagenome sequences from six phototrophic communities (average~ 53 Mbp/site were subjected to multiple taxonomic, phylogenetic and functional analyses. All methods, including G+C content distribution, MEGAN analyses and oligonucleotide frequency-based clustering, provided strong support for the dominant community members present in each site. Cyanobacteria were only observed in non-sulfidic sites; de novo assemblies were obtained for Synechococcus-like populations at Chocolate Pots (CP_7 and Fischerella-like populations at White Creek (WC_6. Chloroflexi-like sequences (esp. Roseiflexus and/or Chloroflexus spp. were observed in all six samples and contained genes involved in bacteriochlorophyll biosynthesis and the 3-hydroxypropionate carbon fixation pathway. Other major sequence assemblies were obtained for a Chlorobiales population from CP_7 (proposed family Thermochlorobacteriaceae, and an anoxygenic, sulfur-oxidizing Thermochromatium-like (Gamma-proteobacteria population from Bath Lake Vista Annex (BLVA_20. Additional sequence coverage is necessary to establish more complete assemblies of other novel bacteria in these sites (e.g., Bacteroidetes and Firmicutes; however, current assemblies suggested that several of these organisms play important roles in heterotrophic and fermentative metabolisms. Definitive linkages were established between several of the dominant phylotypes present in these habitats and important functional

  18. Combining polar organic chemical integrative samplers (POCIS) with toxicity testing to evaluate pesticide mixture effects on natural phototrophic biofilms

    International Nuclear Information System (INIS)

    Pesce, Stephane; Morin, Soizic; Lissalde, Sophie; Montuelle, Bernard; Mazzella, Nicolas

    2011-01-01

    Polar organic chemical integrative samplers (POCIS) are valuable tools in passive sampling methods for monitoring polar organic pesticides in freshwaters. Pesticides extracted from the environment using such methods can be used to toxicity tests. This study evaluated the acute effects of POCIS extracts on natural phototrophic biofilm communities. Our results demonstrate an effect of POCIS pesticide mixtures on chlorophyll a fluorescence, photosynthetic efficiency and community structure. Nevertheless, the range of biofilm responses differs according to origin of the biofilms tested, revealing spatial variations in the sensitivity of natural communities in the studied stream. Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment. - Research highlights: → Polar organic chemical integrative samplers (POCIS) were used for monitoring polar organic pesticides in a contaminated river. → The acute effects of POCIS extracts were tested on natural phototrophic biofilm communities. → POCIS pesticide mixtures affected chlorophyll a fluorescence, photosynthetic efficiency and community structure. → Biofilm responses differed according to origin of the biofilms tested, revealing variations in the sensitivity of natural communities. → Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment. - Pesticide mixtures extracted from POCIS can affect chl a fluorescence, photosynthetic efficiency and community structure of natural biofilms.

  19. Does Aerobic Exercise Influence Intrinsic Brain Activity? An Aerobic Exercise Intervention among Healthy Old Adults

    Directory of Open Access Journals (Sweden)

    Pär Flodin

    2017-08-01

    Full Text Available Previous studies have indicated that aerobic exercise could reduce age related decline in cognition and brain functioning. Here we investigated the effects of aerobic exercise on intrinsic brain activity. Sixty sedentary healthy males and females (64–78 years were randomized into either an aerobic exercise group or an active control group. Both groups recieved supervised training, 3 days a week for 6 months. Multimodal brain imaging data was acquired before and after the intervention, including 10 min of resting state brain functional magnetic resonance imaging (rs-fMRI and arterial spin labeling (ASL. Additionally, a comprehensive battery of cognitive tasks assessing, e.g., executive function and episodic memory was administered. Both the aerobic and the control group improved in aerobic capacity (VO2-peak over 6 months, but a significant group by time interaction confirmed that the aerobic group improved more. Contrary to our hypothesis, we did not observe any significant group by time interactions with regard to any measure of intrinsic activity. To further probe putative relationships between fitness and brain activity, we performed post hoc analyses disregarding group belongings. At baseline, VO2-peak was negativly related to BOLD-signal fluctuations (BOLDSTD in mid temporal areas. Over 6 months, improvements in aerobic capacity were associated with decreased connectivity between left hippocampus and contralateral precentral gyrus, and positively to connectivity between right mid-temporal areas and frontal and parietal regions. Independent component analysis identified a VO2-related increase in coupling between the default mode network and left orbitofrontal cortex, as well as a decreased connectivity between the sensorimotor network and thalamus. Extensive exploratory data analyses of global efficiency, connectome wide multivariate pattern analysis (connectome-MVPA, as well as ASL, did not reveal any relationships between aerobic fitness

  20. Experimentelle und bioinformatische Analyse der aeroben anoxygenen Photosynthese in dem photoheterotrophen Meeresbakterium Dinoroseobacter shibae DFL12

    OpenAIRE

    Tomasch, Jürgen Martin

    2011-01-01

    Bakterielle aerobe anoxygene Photosynthese (AAP) ist ein bedeutenter Mechanismus zur Energiegewinnung in marinen Habitaten. Sie trägt bis zu 5% zum photosynthetischen Elektronentransport an der Oberfläche der Ozeane bei. In dieser Arbeit wurde Dinoroseobacter shibae, ein Vertreter der global verbreiteten marinen Roseobacter-Gruppe genutzt um die Antwort des Transkriptoms auf eine Veränderung der Lichtverhältnisse zu untersuchen. Hierfür wurde kontinuierliche Kultivierung im Chemostat in Kombi...

  1. A Study on Special Characteristics of Sports Aerobics Competitor : The Capacity of Aerobic Power and Isokinetic Strength of Knee Joint

    OpenAIRE

    菊地, はるひ; 佐々木, 浩子

    2004-01-01

    Sports Aerobics is the competitive sports including the complex aerobic step combination and difficulty elements. The competition time is 1 minute and 45±5 seconds. Sports Aerobics requires mainly anaerobic energy for competitive performance. But also it is very important to get the high capacity of aerobic power for performing the perfect execution. In this study, we tried to find out the characteristics for aerobic capacity and leg muscle strength in Sports Aerobics world champions (2 males...

  2. Low aerobic fitness in Brazilian adolescents

    Directory of Open Access Journals (Sweden)

    Diego Augusto Santos Silva

    2015-04-01

    Full Text Available INTRODUCTION: aerobic fitness is considered one of the most important components of health-related physical fitness, with low levels related to increased risk of premature death from all causes, especially cardiovascular diseases. OBJECTIVE: to identify the characteristics of adolescents at higher risk of low levels of aerobic fitness. METHODS: the study included 696 adolescents 15-17 years of age enrolled in public high schools of Florianópolis, southern Brazil. This cross-sectional epidemiological study was conducted in Florianópolis, Santa Catarina, Brazil. Aerobic fitness was measured using the modified Canadian Aerobic Fitness Test mCAFT. Sociodemographic gender, age, school grade, paternal and maternal schooling, socioeconomic status, and anthropometric variables body weight, height, triceps and subscapular skinfold thickness, sexual maturation, physical activity, sedentary behavior, and eating habits were collected. RESULTS: it was found that 31.5% of adolescents had low aerobic fitness levels, being higher in boys 49.2% compared to girls 20.6%. Moreover, girls with sedentary behavior, overweight and high body fat percentage were the groups most likely to have inadequate aerobic fitness. In males, the groups most likely to have inadequate aerobic fitness were those whose parents studied more than eight years, those with low levels of physical activity, and those with inadequate nutrition and excessive body fat. CONCLUSION: low aerobic fitness levels were present in one third of adolescents and was more prevalent in boys. Lifestyle changes, including replacement of sedentary behaviors by physical and sport activities , may assist in improving the aerobic fitness of Brazilian adolescents.

  3. Early anaerobic metabolisms

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene; Rosing, Minik T; Bjerrum, Christian

    2006-01-01

    probably driven by the cycling of H2 and Fe2+ through primary production conducted by anoxygenic phototrophs. Interesting and dynamic ecosystems would have also been driven by the microbial cycling of sulphur and nitrogen species, but their activity levels were probably not so great. Despite the diversity......Before the advent of oxygenic photosynthesis, the biosphere was driven by anaerobic metabolisms. We catalogue and quantify the source strengths of the most probable electron donors and electron acceptors that would have been available to fuel early-Earth ecosystems. The most active ecosystems were...... of potential early ecosystems, rates of primary production in the early-Earth anaerobic biosphere were probably well below those rates observed in the marine environment. We shift our attention to the Earth environment at 3.8Gyr ago, where the earliest marine sediments are preserved. We calculate, consistent...

  4. Field assessment of semi-aerobic condition and the methane correction factor for the semi-aerobic landfills provided by IPCC guidelines

    International Nuclear Information System (INIS)

    Jeong, Sangjae; Nam, Anwoo; Yi, Seung-Muk; Kim, Jae Young

    2015-01-01

    Highlights: • CH 4 /CO 2 and CH 4 + CO 2 % are proposed as indices to evaluate semi-aerobic landfills. • A landfill which CH 4 /CO 2 > 1.0 is difficult to be categorized as semi-aerobic landfill. • Field conditions should be carefully investigated to determine landfill types. • The MCF default value for semi-aerobic landfills underestimates the methane emissions. - Abstract: According to IPCC guidelines, a semi-aerobic landfill site produces one-half of the amount of CH 4 produced by an equally-sized anaerobic landfill site. Therefore categorizing the landfill type is important on greenhouse gas inventories. In order to assess semi-aerobic condition in the sites and the MCF value for semi-aerobic landfill, landfill gas has been measured from vent pipes in five semi-aerobically designed landfills in South Korea. All of the five sites satisfied requirements of semi-aerobic landfills in 2006 IPCC guidelines. However, the ends of leachate collection pipes which are main entrance of air in the semi-aerobic landfill were closed in all five sites. The CH 4 /CO 2 ratio in landfill gas, indicator of aerobic and anaerobic decomposition, ranged from 1.08 to 1.46 which is higher than the values (0.3–1.0) reported for semi-aerobic landfill sites and is rather close to those (1.0–2.0) for anaerobic landfill sites. The low CH 4 + CO 2 % in landfill gas implied air intrusion into the landfill. However, there was no evidence that air intrusion has caused by semi-aerobic design and operation. Therefore, the landfills investigated in this study are difficult to be classified as semi-aerobic landfills. Also MCF of 0.5 may significantly underestimate methane emissions compared to other researches. According to the carbon mass balance analyses, the higher MCF needs to be proposed for semi-aerobic landfills. Consequently, methane emission estimate should be based on field evaluation for the semi-aerobically designed landfills

  5. Field assessment of semi-aerobic condition and the methane correction factor for the semi-aerobic landfills provided by IPCC guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Sangjae [Department of Civil and Environmental Engineering, College of Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Nam, Anwoo [Korea Environment Corporation, 42 Hwangyeong-ro, Seo-gu, Incheon 404-170 (Korea, Republic of); Yi, Seung-Muk [Department of Environmental Health, School of Public Health, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, Jae Young, E-mail: jaeykim@snu.ac.kr [Department of Civil and Environmental Engineering, College of Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of)

    2015-02-15

    Highlights: • CH{sub 4}/CO{sub 2} and CH{sub 4} + CO{sub 2}% are proposed as indices to evaluate semi-aerobic landfills. • A landfill which CH{sub 4}/CO{sub 2} > 1.0 is difficult to be categorized as semi-aerobic landfill. • Field conditions should be carefully investigated to determine landfill types. • The MCF default value for semi-aerobic landfills underestimates the methane emissions. - Abstract: According to IPCC guidelines, a semi-aerobic landfill site produces one-half of the amount of CH{sub 4} produced by an equally-sized anaerobic landfill site. Therefore categorizing the landfill type is important on greenhouse gas inventories. In order to assess semi-aerobic condition in the sites and the MCF value for semi-aerobic landfill, landfill gas has been measured from vent pipes in five semi-aerobically designed landfills in South Korea. All of the five sites satisfied requirements of semi-aerobic landfills in 2006 IPCC guidelines. However, the ends of leachate collection pipes which are main entrance of air in the semi-aerobic landfill were closed in all five sites. The CH{sub 4}/CO{sub 2} ratio in landfill gas, indicator of aerobic and anaerobic decomposition, ranged from 1.08 to 1.46 which is higher than the values (0.3–1.0) reported for semi-aerobic landfill sites and is rather close to those (1.0–2.0) for anaerobic landfill sites. The low CH{sub 4} + CO{sub 2}% in landfill gas implied air intrusion into the landfill. However, there was no evidence that air intrusion has caused by semi-aerobic design and operation. Therefore, the landfills investigated in this study are difficult to be classified as semi-aerobic landfills. Also MCF of 0.5 may significantly underestimate methane emissions compared to other researches. According to the carbon mass balance analyses, the higher MCF needs to be proposed for semi-aerobic landfills. Consequently, methane emission estimate should be based on field evaluation for the semi-aerobically designed landfills.

  6. Composition changes of phototrophic microbial communities along the salinity gradient in the solar saltern evaporation ponds of Eilat, Israel

    Czech Academy of Sciences Publication Activity Database

    Řeháková, Klára; Zapomělová, Eliška; Prášil, Ondřej; Veselá, J.; Medová, Hana; Oren, A.

    2009-01-01

    Roč. 636, č. 1 (2009), s. 77-88 ISSN 0018-8158 R&D Projects: GA ČR GA206/06/0462; GA AV ČR KJB600960703; GA AV ČR 1QS600170504; GA AV ČR 1QS500200570 Institutional research plan: CEZ:AV0Z60050516; CEZ:AV0Z60170517; CEZ:AV0Z50200510 Keywords : phototrophic microbial community * salterns * species composition Subject RIV: EF - Botanics Impact factor: 1.754, year: 2009

  7. Isoprenoid biosynthesis in eukaryotic phototrophs: A spotlight on algae

    Energy Technology Data Exchange (ETDEWEB)

    Lohr M.; Schwender J.; Polle, J. E. W.

    2012-04-01

    Isoprenoids are one of the largest groups of natural compounds and have a variety of important functions in the primary metabolism of land plants and algae. In recent years, our understanding of the numerous facets of isoprenoid metabolism in land plants has been rapidly increasing, while knowledge on the metabolic network of isoprenoids in algae still lags behind. Here, current views on the biochemistry and genetics of the core isoprenoid metabolism in land plants and in the major algal phyla are compared and some of the most pressing open questions are highlighted. Based on the different evolutionary histories of the various groups of eukaryotic phototrophs, we discuss the distribution and regulation of the mevalonate (MVA) and the methylerythritol phosphate (MEP) pathways in land plants and algae and the potential consequences of the loss of the MVA pathway in groups such as the green algae. For the prenyltransferases, serving as gatekeepers to the various branches of terpenoid biosynthesis in land plants and algae, we explore the minimal inventory necessary for the formation of primary isoprenoids and present a preliminary analysis of their occurrence and phylogeny in algae with primary and secondary plastids. The review concludes with some perspectives on genetic engineering of the isoprenoid metabolism in algae.

  8. Localized electron transfer rates and microelectrode-based enrichment of microbial communities within a phototrophic microbial mat

    Directory of Open Access Journals (Sweden)

    Jerome eBabauta

    2014-01-01

    Full Text Available Phototrophic microbial mats frequently exhibit sharp, light-dependent redox gradients that regulate microbial respiration on specific electron acceptors as a function of depth. In this work, a benthic phototrophic microbial mat from Hot Lake, a hypersaline, epsomitic lake located near Oroville in north-central Washington, was used to develop a microscale electrochemical method to study local electron transfer processes within the mat. To characterize the physicochemical variables influencing electron transfer, we initially quantified redox potential, pH and dissolved oxygen gradients by depth in the mat under photic and aphotic conditions. We further demonstrated that power output of a mat fuel cell was light-dependent. To study local electron transfer processes, we deployed a microscale electrode (microelectrode with tip size ~20 µm. To enrich a subset of microorganisms capable of interacting with the microelectrode, we anodically polarized the microelectrode in the mat. Subsequently, to characterize the microelectrode-associated community and compare it to the neighboring mat community, we performed amplicon sequencing of the V1-V3 region of the 16S gene. Differences in Bray-Curtis beta diversity, illustrated by large changes in relative abundance at the phylum level, suggested successful enrichment of specific mat community members on the microelectrode surface. The microelectrode-associated community exhibited substantially reduced alpha diversity and elevated relative abundances of Prosthecochloris, Loktanella, Catellibacterium, other unclassified members of Rhodobacteraceae, Thiomicrospira, and Limnobacter, compared with the community at an equivalent depth in the mat. Our results suggest that local electron transfer to an anodically polarized microelectrode selected for a specific microbial population, with substantially more abundance and diversity of sulfur-oxidizing phylotypes compared with the neighboring mat community.

  9. Localized electron transfer rates and microelectrode-based enrichment of microbial communities within a phototrophic microbial mat.

    Science.gov (United States)

    Babauta, Jerome T; Atci, Erhan; Ha, Phuc T; Lindemann, Stephen R; Ewing, Timothy; Call, Douglas R; Fredrickson, James K; Beyenal, Haluk

    2014-01-01

    Phototrophic microbial mats frequently exhibit sharp, light-dependent redox gradients that regulate microbial respiration on specific electron acceptors as a function of depth. In this work, a benthic phototrophic microbial mat from Hot Lake, a hypersaline, epsomitic lake located near Oroville in north-central Washington, was used to develop a microscale electrochemical method to study local electron transfer processes within the mat. To characterize the physicochemical variables influencing electron transfer, we initially quantified redox potential, pH, and dissolved oxygen gradients by depth in the mat under photic and aphotic conditions. We further demonstrated that power output of a mat fuel cell was light-dependent. To study local electron transfer processes, we deployed a microscale electrode (microelectrode) with tip size ~20 μm. To enrich a subset of microorganisms capable of interacting with the microelectrode, we anodically polarized the microelectrode at depth in the mat. Subsequently, to characterize the microelectrode-associated community and compare it to the neighboring mat community, we performed amplicon sequencing of the V1-V3 region of the 16S gene. Differences in Bray-Curtis beta diversity, illustrated by large changes in relative abundance at the phylum level, suggested successful enrichment of specific mat community members on the microelectrode surface. The microelectrode-associated community exhibited substantially reduced alpha diversity and elevated relative abundances of Prosthecochloris, Loktanella, Catellibacterium, other unclassified members of Rhodobacteraceae, Thiomicrospira, and Limnobacter, compared with the community at an equivalent depth in the mat. Our results suggest that local electron transfer to an anodically polarized microelectrode selected for a specific microbial population, with substantially more abundance and diversity of sulfur-oxidizing phylotypes compared with the neighboring mat community.

  10. Genomewide characterisation of the genetic diversity of carotenogenesis in bacteria of the order Sphingomonadales.

    Science.gov (United States)

    Siddaramappa, Shivakumara; Viswanathan, Vandana; Thiyagarajan, Saravanamuthu; Narjala, Anushree

    2018-04-05

    The order Sphingomonadales is a taxon of bacteria with a variety of physiological features and carotenoid pigments. Some of the coloured strains within this order are known to be aerobic anoxygenic phototrophs that contain characteristic photosynthesis gene clusters (PGCs). Previous work has shown that majority of the ORFs putatively involved in the biosynthesis of C40 carotenoids are located outside the PGCs in these strains. The main purpose of this study was to understand the genetic basis for the various colour/carotenoid phenotypes of the strains of Sphingomonadales. Comparative analyses of the genomes of 41 strains of this order revealed that there were different patterns of clustering of carotenoid biosynthesis (crt) ORFs, with four ORF clusters being the most common. The analyses also revealed that co-occurrence of crtY and crtI is an evolutionarily conserved feature in Sphingomonadales and other carotenogenic bacteria. The comparisons facilitated the categorisation of bacteria of this order into four groups based on the presence of different crt ORFs. Yellow coloured strains most likely accumulate nostoxanthin, and contain six ORFs (group I: crtE, crtB, crtI, crtY, crtZ, crtG). Orange coloured strains may produce adonixanthin, astaxanthin, canthaxanthin and erythroxanthin, and contain seven ORFs (group II: crtE, crtB, crtI, crtY, crtZ, crtG, crtW). Red coloured strains may accumulate astaxanthin, and contain six ORFs (group III: crtE, crtB, crtI, crtY, crtZ, crtW). Non-pigmented strains may contain a smaller subset of crt ORFs, and thus fail to produce any carotenoids (group IV). The functions of many of these ORFs remain to be characterised.

  11. Aerobic rice mechanization: techniques for crop establishment

    Science.gov (United States)

    Khusairy, K. M.; Ayob, H.; Chan, C. S.; Fauzi, M. I. Mohamed; Mohamad Fakhrul, Z. O.; Shahril Shah, G. S. M.; Azlan, O.; Rasad, M. A.; Hashim, A. M.; Arshad, Z.; E, E. Ibrahim; Saifulizan, M. N.

    2015-12-01

    Rice being the staple food crops, hundreds of land races in it makes the diversity of rice crops. Aerobic rice production was introduced which requires much less water input to safeguard and sustain the rice production and conserve water due to decreasing water resources, climatic changes and competition from urban and industrial users. Mechanization system plays an important role for the success of aerobic rice cultivation. All farming activities for aerobic rice production are run on aerobic soil conditions. Row seeder mechanization system is developed to replace conventional seeding technique on the aerobic rice field. It is targeted for small and the large scale aerobic rice farmers. The aero - seeder machine is used for the small scale aerobic rice field, while the accord - seeder is used for the large scale aerobic rice field. The use of this mechanization machine can eliminate the tedious and inaccurate seeding operations reduce labour costs and increases work rate. The machine is easy to operate and it can increase crop establishment rate. It reduce missing hill, increasing planting and crop with high yield can be produce. This machine is designed for low costs maintenance and it is easy to dismantle and assemble during maintenance and it is safe to be used.

  12. Could photosynthesis function on Proxima Centauri b?

    Science.gov (United States)

    Ritchie, Raymond J.; Larkum, Anthony W. D.; Ribas, Ignasi

    2018-04-01

    bacteria (photosynthesis. Nevertheless, a substantial aerobic or anaerobic ecology is possible on Proxima Centauri b. Protocols to recognize the biogenic signature of anoxygenic photosynthesis are needed.

  13. Systems-level Proteomics of Two Ubiquitous Leaf Commensals Reveals Complementary Adaptive Traits for Phyllosphere Colonization*

    Science.gov (United States)

    Müller, Daniel B.; Schubert, Olga T.; Röst, Hannes; Aebersold, Ruedi; Vorholt, Julia A.

    2016-01-01

    Plants are colonized by a diverse community of microorganisms, the plant microbiota, exhibiting a defined and conserved taxonomic structure. Niche separation based on spatial segregation and complementary adaptation strategies likely forms the basis for coexistence of the various microorganisms in the plant environment. To gain insights into organism-specific adaptations on a molecular level, we selected two exemplary community members of the core leaf microbiota and profiled their proteomes upon Arabidopsis phyllosphere colonization. The highly quantitative mass spectrometric technique SWATH MS was used and allowed for the analysis of over two thousand proteins spanning more than three orders of magnitude in abundance for each of the model strains. The data suggest that Sphingomonas melonis utilizes amino acids and hydrocarbon compounds during colonization of leaves whereas Methylobacterium extorquens relies on methanol metabolism in addition to oxalate metabolism, aerobic anoxygenic photosynthesis and alkanesulfonate utilization. Comparative genomic analyses indicates that utilization of oxalate and alkanesulfonates is widespread among leaf microbiota members whereas, aerobic anoxygenic photosynthesis is almost exclusively found in Methylobacteria. Despite the apparent niche separation between these two strains we also found a relatively small subset of proteins to be coregulated, indicating common mechanisms, underlying successful leaf colonization. Overall, our results reveal for two ubiquitous phyllosphere commensals species-specific adaptations to the host environment and provide evidence for niche separation within the plant microbiota. PMID:27457762

  14. In silico approaches to study mass and energy flows in microbial consortia: a syntrophic case study

    Directory of Open Access Journals (Sweden)

    Mallette Natasha

    2009-12-01

    Full Text Available Abstract Background Three methods were developed for the application of stoichiometry-based network analysis approaches including elementary mode analysis to the study of mass and energy flows in microbial communities. Each has distinct advantages and disadvantages suitable for analyzing systems with different degrees of complexity and a priori knowledge. These approaches were tested and compared using data from the thermophilic, phototrophic mat communities from Octopus and Mushroom Springs in Yellowstone National Park (USA. The models were based on three distinct microbial guilds: oxygenic phototrophs, filamentous anoxygenic phototrophs, and sulfate-reducing bacteria. Two phases, day and night, were modeled to account for differences in the sources of mass and energy and the routes available for their exchange. Results The in silico models were used to explore fundamental questions in ecology including the prediction of and explanation for measured relative abundances of primary producers in the mat, theoretical tradeoffs between overall productivity and the generation of toxic by-products, and the relative robustness of various guild interactions. Conclusion The three modeling approaches represent a flexible toolbox for creating cellular metabolic networks to study microbial communities on scales ranging from cells to ecosystems. A comparison of the three methods highlights considerations for selecting the one most appropriate for a given microbial system. For instance, communities represented only by metagenomic data can be modeled using the pooled method which analyzes a community's total metabolic potential without attempting to partition enzymes to different organisms. Systems with extensive a priori information on microbial guilds can be represented using the compartmentalized technique, employing distinct control volumes to separate guild-appropriate enzymes and metabolites. If the complexity of a compartmentalized network creates an

  15. Resistance training and aerobic training improve muscle strength and aerobic capacity in chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Markvardsen, Lars H; Overgaard, Kristian; Heje, Karen; Sindrup, Søren H; Christiansen, Ingelise; Vissing, John; Andersen, Henning

    2018-01-01

    We investigated the effects of aerobic and resistance exercise in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Eighteen CIDP patients treated with subcutaneous immunoglobulin performed 12 weeks of aerobic exercise and 12 weeks of resistance exercise after a run-in period of 12 weeks without exercise. Three times weekly the participants performed aerobic exercise on an ergometer bike or resistance exercise with unilateral training of knee and elbow flexion/extension. Primary outcomes were maximal oxygen consumption velocity (VO 2 -max) and maximal combined isokinetic muscle strength (cIKS) of knee and elbow flexion/extension. VO 2 -max and muscle strength were unchanged during run-in (-4.9% ± 10.3%, P = 0.80 and -3.7% ± 10.1%, P = 0.17, respectively). Aerobic exercise increased VO 2 -max by 11.0% ± 14.7% (P = 0.02). Resistance exercise resulted in an increase of 13.8% ± 16.0% (P = 0.0004) in cIKS. Aerobic exercise training and resistance exercise training improve fitness and strength in CIDP patients. Muscle Nerve 57: 70-76, 2018. © 2017 Wiley Periodicals, Inc.

  16. Weathering of a Roman Mosaic-A Biological and Quantitative Study on In Vitro Colonization of Calcareous Tesserae by Phototrophic Microorganisms.

    Directory of Open Access Journals (Sweden)

    Addolorata Marasco

    Full Text Available The potential impact of cyanobacteria and microalgae on the weathering of calcareous tesserae from a Roman mosaic of the II Century CE has been followed through in vitro experiments. Laboratory tests were carried out by inoculating mosaic tiles with single strains of Cyanobacteria or Chlorophyta to evaluate the roles of pioneer phototrophic microrganism on the resulting architecture of biofilms. The interaction between tesserae and strains was assessed at the whole substratum and micrometer scales, by image analysis and Confocal Laser Scanning (CLS microscopy, respectively. The biofilm surface coverage on each tessera varied from 19% (Fischerella ambigua to 97% (Microcoleus autumnalis. Cyanobacteria showed a better growth on calcareous tesserae, whereas the only green alga attaining a superficial coverage higher than 50% was Coelastrella rubescens. CLS microscopy evidenced two different types of spatial arrangement of the phototrophic organisms on the tesserae, that were defined as compact or porous, respectively. In the first one was measured a reduced number of empty spaces between cells or filaments, whereas in the second type, a reticulate texture allowed the presence of numerous empty volumes. The colonization processes observed are an intrinsic characteristic of each strain. We have proposed a colonization index IC as a sensible tool to describe, in a quantitative way, the pioneering attitude of each photosynthetic microorganism to colonize lithic substrates under laboratory conditions.

  17. Exposure of phototrophs to 548 days in low Earth orbit: microbial selection pressures in outer space and on early earth.

    Science.gov (United States)

    Cockell, Charles S; Rettberg, Petra; Rabbow, Elke; Olsson-Francis, Karen

    2011-10-01

    An epilithic microbial community was launched into low Earth orbit, and exposed to conditions in outer space for 548 days on the European Space Agency EXPOSE-E facility outside the International Space Station. The natural phototroph biofilm was augmented with akinetes of Anabaena cylindrica and vegetative cells of Nostoc commune and Chroococcidiopsis. In space-exposed dark controls, two algae (Chlorella and Rosenvingiella spp.), a cyanobacterium (Gloeocapsa sp.) and two bacteria associated with the natural community survived. Of the augmented organisms, cells of A. cylindrica and Chroococcidiopsis survived, but no cells of N. commune. Only cells of Chroococcidiopsis were cultured from samples exposed to the unattenuated extraterrestrial ultraviolet (UV) spectrum (>110 nm or 200 nm). Raman spectroscopy and bright-field microscopy showed that under these conditions the surface cells were bleached and their carotenoids were destroyed, although cell morphology was preserved. These experiments demonstrate that outer space can act as a selection pressure on the composition of microbial communities. The results obtained from samples exposed to >200 nm UV (simulating the putative worst-case UV exposure on the early Earth) demonstrate the potential for epilithic colonization of land masses during that time, but that UV radiation on anoxic planets can act as a strong selection pressure on surface-dwelling organisms. Finally, these experiments have yielded new phototrophic organisms of potential use in biomass and oxygen production in space exploration.

  18. Aerobic sludge granulation for simultaneous anaerobic decolorization and aerobic aromatic amines mineralization for azo dye wastewater treatment.

    Science.gov (United States)

    Yan, Lawrence K Q; Fung, Ka Y; Ng, Ka M

    2018-06-01

    In this study, the capability of using aerobic granules to undergo simultaneous anaerobic decolorization and aerobic aromatic amines degradation was demonstrated for azo dye wastewater treatment. An integrated acclimation-granulation process was devised, with Mordant Orange 1 as the model pollutant. Performance tests were carried out in a batch column reactor to evaluate the effect of various operating parameters. The optimal condition was to use 1.0-1.7 mm (1.51 ± 0.33 mm) granules, 5 g/L biomass, and 4000 mg/L organics as nutrient; and supplement the wastewater with 1  mg/L dissolved oxygen. This led to a dye mineralization of 61 ± 2%, an anaerobic dye removal of 88 ± 1%, and an aerobic aromatic amines removal of 70 ± 3% within 48 h. This study showed that simultaneous anaerobic/aerobic process by aerobic granules could be a possible alternative to the conventional activated sludge process.

  19. Summary report on the aerobic degradation of diesel fuel and the degradation of toluene under aerobic, denitrifying and sulfate reducing conditions

    International Nuclear Information System (INIS)

    Coyne, P.; Smith, G.

    1995-01-01

    This report contains a number of studies that were performed to better understand the technology of the biodegradation of petroleum hydrocarbons. Topics of investigation include the following: diesel fuel degradation by Rhodococcus erythropolis; BTEX degradation by soil isolates; aerobic degradation of diesel fuel-respirometry; aerobic degradation of diesel fuel-shake culture; aerobic toluene degradation by A3; effect of HEPES, B1, and myo-inositol addition on the growth of A3; aerobic and anaerobic toluene degradation by contaminated soils; denitrifying bacteria MPNs; sulfate-reducing bacteria MPNs; and aerobic, DNB and SRB enrichments

  20. Singlet-triplet fission of carotenoid excitation in light-harvesting LH2 complexes of purple phototrophic bacteria.

    Science.gov (United States)

    Klenina, I B; Makhneva, Z K; Moskalenko, A A; Gudkov, N D; Bolshakov, M A; Pavlova, E A; Proskuryakov, I I

    2014-03-01

    The current generally accepted structure of light-harvesting LH2 complexes from purple phototrophic bacteria conflicts with the observation of singlet-triplet carotenoid excitation fission in these complexes. In LH2 complexes from the purple bacterium Allochromatium minutissimum, a drop in the efficiency of carotenoid triplet generation is demonstrated, which correlates with the extent of selective photooxidation of bacteriochlorophylls absorbing at ~850 nm. We conclude that singlet-triplet fission of carotenoid excitation proceeds with participation of these excitonically coupled bacteriochlorophylls. In the framework of the proposed mechanism, the contradiction between LH2 structure and photophysical properties of carotenoids is eliminated. The possibility of singlet-triplet excitation fission involving a third mediator molecule was not considered earlier.

  1. [Moderately haloalkaliphilic aerobic methylobacteria].

    Science.gov (United States)

    Trotsenko, Iu A; Doronina, N V; Li, Ts D; Reshetnikov, A S

    2007-01-01

    Aerobic methylobacteria utilizing oxidized and substituted methane derivatives as carbon and energy sources are widespread in nature and involved in the global carbon cycle, being a unique biofilter on the path of these C1 compounds from different ecosystems to the atmosphere. New data on the biological features of moderately halophilic, neutrophilic, and alkaliphilic methylobacteria isolated from biotopes with higher osmolarity (seas, saline and soda lakes, saline soils, and deteriorating marble) are reviewed. Particular attention is paid to the latest advances in the study of the mechanisms of osmoadaptation of aerobic moderately haloalkaliphilic methylobacteria: formation of osmolytes, in particular, molecular and genetic aspects of biosynthesis of the universal bioprotectant ectoine. The prospects for further studies of the physiological and biochemical principles of haloalkalophily and for the application of haloalkaliphilic aerobic methylobacteria in biosynthesis and biodegradation are discussed.

  2. Neuromodulation of Aerobic Exercise—A Review

    Directory of Open Access Journals (Sweden)

    Saskia eHeijnen

    2016-01-01

    Full Text Available Running, and aerobic exercise in general, is a physical activity that increasingly many people engage in but that also has become popular as a topic for scientific research. Here we review the available studies investigating whether and to which degree aerobic exercise modulates hormones, amino acids, and neurotransmitters levels. In general, it seems that factors such as genes, gender, training status, and hormonal status need to be taken into account to gain a better understanding of the neuromodular underpinnings of aerobic exercise. More research using longitudinal studies and considering individual differences is necessary to determine actual benefits. We suggest that, in order to succeed, aerobic exercise programs should include optimal periodization, prevent overtraining and be tailored to interindividual differences, including neuro-developmental and genetically-based factors.

  3. Mushroom speleothems: Stromatolites that formed in the absence of phototrophs

    Science.gov (United States)

    Bontognali, Tomaso; D'Angeli, Ilenia; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano; Gonzales, Esteban; DeWaele, Jo

    2016-04-01

    Unusual speleothems resembling giant mushrooms occur in Santa Catalina Cave, Cuba. Although these mineral buildups are considered a natural heritage, their composition and formation mechanism remain poorly understood. Here we characterize their morphology and mineralogy and present a model for their genesis. We propose that the mushrooms, which are mainly comprised of calcite and aragonite, formed during four different phases within an evolving cave environment. The stipe of the mushroom is an assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts that were subsequently encrusted by cave clouds (mammilaries). More peculiar is the cap of the mushroom, which is morphologically similar to cerebroid stromatolites and thrombolites of microbial origin occurring in marine environments. Scanning electron microscopy investigations of this last unit revealed the presence of fossilized extracellular polymeric substances (EPS) - the constituents of biofilms and microbial mats. These organic microstructures are mineralized with Ca-carbonate, suggesting that the mushroom cap formed through a microbially-influenced mineralization process. The existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence of phototrophs) has interesting implications for the study of fossil microbialites preserved in ancient rocks, which are today considered as one of the earliest evidence for life on Earth.

  4. Mushroom speleothems: Stromatolites that formed in the absence of phototrophs

    Directory of Open Access Journals (Sweden)

    Tomaso eBontognali

    2016-04-01

    Full Text Available Unusual speleothems resembling giant mushrooms occur in Santa Catalina Cave, Cuba. Although these mineral buildups are considered a natural heritage, their composition and formation mechanism remain poorly understood. Here we characterize their morphology and mineralogy and present a model for their genesis. We propose that the mushrooms, which are mainly comprised of calcite and aragonite, formed during four different phases within an evolving cave environment. The stipe of the mushroom is an assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts that were subsequently encrusted by cave clouds (mammilaries. More peculiar is the cap of the mushroom, which is morphologically similar to cerebroid stromatolites and thrombolites of microbial origin occurring in marine environments. Scanning electron microscopy investigations of this last unit revealed the presence of fossilized extracellular polymeric substances (EPS – the constituents of biofilms and microbial mats. These organic microstructures are mineralized with Ca-carbonate, suggesting that the mushroom cap formed through a microbially-influenced mineralization process. The existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence of phototrophs has interesting implications for the study of fossil microbialites preserved in ancient rocks, which are today considered as one of the earliest evidence for life on Earth.

  5. SYSTEMATIZATION OF THE BASIC STEPS OF THE STEP-AEROBICS

    Directory of Open Access Journals (Sweden)

    Darinka Korovljev

    2011-03-01

    Full Text Available Following the development of the powerful sport industry, in front of us appeared a lot of new opportunities for creating of the new programmes of exercising with certain requisites. One of such programmes is certainly step-aerobics. Step-aerobics can be defined as a type of aerobics consisting of the basic aerobic steps (basic steps applied in exercising on stepper (step bench, with a possibility to regulate its height. Step-aerobics itself can be divided into several groups, depending on the following: type of music, working methods and adopted knowledge of the attendants. In this work, the systematization of the basic steps in step-aerobics was made on the basis of the following criteria: steps origin, number of leg motions in stepping and relating the body support at the end of the step. Systematization of the basic steps of the step-aerobics is quite significant for making a concrete review of the existing basic steps, thus making creation of the step-aerobics lesson easier

  6. Enhancement of phototrophic hydrogen production by Rhodobacter sphaeroides ZX-5 using a novel strategy - shaking and extra-light supplementation approach

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xu; Wang, Yong-Hong; Zhang, Si-Liang; Chu, Ju; Zhang, Ming; Huang, Ming-Zhi; Zhuang, Ying-Ping [State Key Laboratory of Bioreactor Engineering, P.O. Box 329, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China)

    2009-12-15

    Biohydrogen has gained attention due to its potential as a sustainable alternative to conventional methods for hydrogen production. In this study, the effect of light intensity as well as cultivation method (standing- and shaking-culture) on the cell growth and hydrogen production of Rhodobacter sphaeroides ZX-5 were investigated in 38-ml anaerobic photobioreactor with RCVBN medium. Thus, a novel shaking and extra-light supplementation (SELS) approach was developed to enhance the phototrophic H{sub 2} production by R. sphaeroides ZX-5 using malate as the sole carbon source. The optimum illumination condition for shaking-culture by strain ZX-5 increased to 7000-8000 lux, markedly higher than that for standing-culture (4000-5000 lux). Under shaking and elevated illumination (7000-8000 lux), the culture was effective in promoting photo-H{sub 2} production, resulting in a 59% and 56% increase of the maximum and average hydrogen production rate, respectively, in comparison with the culture under standing and 4000-5000 lux conditions. The highest hydrogen-producing rate of 165.9 ml H{sub 2}/l h was observed under the application of SELS approach. To our knowledge, this record is currently the highest hydrogen production rate of non-immobilized purple non-sulphur (PNS) bacteria. This optimal performance of photo-H{sub 2} production using SELS approach is a favorable choice of sustainable and economically feasible strategy to improve phototrophic H{sub 2} production efficiency. (author)

  7. Aerobic exercise deconditioning and countermeasures during bed rest.

    Science.gov (United States)

    Lee, Stuart M C; Moore, Alan D; Everett, Meghan E; Stenger, Michael B; Platts, Steven H

    2010-01-01

    Bed rest is a well-accepted model for spaceflight in which the physiologic adaptations, particularly in the cardiovascular system, are studied and potential countermeasures can be tested. Bed rest without countermeasures results in reduced aerobic capacity and altered submaximal exercise responses. Aerobic endurance and factors which may impact prolonged exercise, however, have not been well studied. The initial loss of aerobic capacity is rapid, occurring in parallel with the loss of plasma volume. Thereafter, the reduction in maximal aerobic capacity proceeds more slowly and is influenced by central and peripheral adaptation. Exercise capacity can be maintained during bed rest and may be improved during recovery with appropriate countermeasures. Plasma volume restoration, resistive exercise, orthostatic stress, aerobic exercise, and aerobic exercise plus orthostatic stress all have been tested with varying levels of success. However, the optimal combination of elements-exercise modality, intensity, duration, muscle groups exercised and frequency of aerobic exercise, orthostatic stress, and supplementary resistive or anaerobic exercise training-has not been systematically evaluated. Currently, frequent (at least 3 days per week) bouts of intense exercise (interval-style and near maximal) with orthostatic stress appears to be the most efficacious method to protect aerobic capacity during bed rest. Further refinement of protocols and countermeasure hardware may be necessary to insure the success of countermeasures in the unique environment of space.

  8. Phototrophic biofilms of restored fields in the Rhenish lignite mining area: development of soil algal, bacterial, and fungal biomasses

    Energy Technology Data Exchange (ETDEWEB)

    Jahnke, K.; Priefer, U.B. [Rhein Westfal TH Aachen, Aachen (Germany)

    2002-07-01

    The formation of phototrophic biofilms in three fields under restoration of a lignite-mining area was recorded over 3 years of lucerne cultivation in terms of biomass carbon from algae, bacteria and fungi. The primary phase of biofilm development on the humus- and nitrogen deficient uppermost soil surfaces was dominated by algae. The ratio of algal carbon to heterotrophic bacterial and fungal carbon ranged from 1:0.4 to 1:2. Only during this initial developmental stage did the total microfloral carbon exceed 10% of the overall organic carbon content. With time, the ratios between algal and heterotrophic microbial carbon increased to 1:10 which was mainly due to decomposed plant residues and humus accumulation supporting the growth of bacteria and fungi. At this later stage of field development the calculated amount of bacterial and fungal carbon associated with the algae was still at least 8% of total heterotrophic microbial carbon and could even reach 20%. Bacterial and fungal biomasses were primarily governed by the organic carbon content (r = 0.81), but fluctuations-up to 50% and occurring mostly simultaneously for the three microfloral members-were observed in response to temperature and moisture conditions. The calculated in situ doubling times were 8 days (algae), 9 days (bacteria) and 14 days (fungi), respectively. Insight is given into the dynamics of phototrophic biofilm development and the abiotic factors affecting them during early phases of arable soil restoration. The results indicate that biomass changes expressed as the respective ratios between their microfloral members are a useful tool to characterise the different developmental stages of terrestrial biofilms.

  9. Small changes in Cu redox state and speciation generate large isotope fractionation during adsorption and incorporation of Cu by a phototrophic biofilm

    Science.gov (United States)

    Coutaud, Margot; Méheut, Merlin; Glatzel, Pieter; Pokrovski, Gleb S.; Viers, Jérôme; Rols, Jean-Luc; Pokrovsky, Oleg S.

    2018-01-01

    Despite the importance of phototrophic biofilms in metal cycling in freshwater systems, metal isotope fractionation linked to metal adsorption and uptake by biofilm remains very poorly constrained. Here, copper isotope fractionation by a mature phototrophic biofilm during Cu surface adsorption and incorporation was studied in batch reactor (BR) and open drip flow reactor (DFR) systems at ambient conditions. X-ray Absorption Spectroscopy (both Near Edge Structure, XANES, and Extended Fine Structure, EXAFS) at Cu K-edge of the biofilm after its interaction with Cu in BR experiments allowed characterizing the molecular structure of assimilated Cu and quantifying the degree of CuII to CuI reduction linked to Cu assimilation. For both BR and DFR experiments, Cu adsorption caused enrichment in heavy isotope at the surface of the biofilm relative to the aqueous solution, with an apparent enrichment factor for the adsorption process, ε65Cuads, of +1.1 ± 0.3‰. In contrast, the isotope enrichment factor during copper incorporation into the biofilm (ε65Cuinc) was highly variable, ranging from -0.6 to +0.8‰. This variability of the ε65Cuinc value was likely controlled by Cu cellular uptake via different transport pathways resulting in contrasting fractionation. Specifically, the CuII storage induced enrichment in heavy isotope, whereas the toxicity response of the biofilm to Cu exposure resulted in reduction of CuII to CuI, thus yielding the biofilm enrichment in light isotope. EXAFS analyses suggested that a major part of the Cu assimilated by the biofilm is bound to 5.1 ± 0.3 oxygen or nitrogen atoms, with a small proportion of Cu linked to sulfur atoms (NS biofilm exhibited a similar trend over time of exposure. Our study demonstrates the complexity of biological processes associated with live phototrophic biofilms, which produce large and contrasting isotope fractionations following rather small Cu redox and speciation changes during uptake, storage or release of

  10. Aerobic exercise in pulmonary rehabilitation

    Directory of Open Access Journals (Sweden)

    Thiago Brasileiro de Vasconcelos

    2013-01-01

    Full Text Available The aim of this study was to conduct a literature review on the usefulness of aerobic exercise in pulmonary rehabilitation. This is an exploratory study of literature through the electronic databases Medline, Lilacs, Scielo, Pubmed and Google Scholar, published between 1996 and 2012, conducted during the period February to May 2012 with the following keywords: COPD, pulmonary rehabilitation, aerobic exercises, physical training, quality of life. The change in pulmonary function and dysfunction of skeletal muscles that result in exercise intolerance and reduced fitness and may cause social isolation, depression, anxiety and addiction. The training exercise is the most important component of the program of pulmonary rehabilitation where the aerobic training provides consistent results in clinical improvement in levels of exercise tolerance and decreased dyspnea generating more benefits to the body, reducing the chance of cardiovascular disease and improves quality and expectation of life. We demonstrated that the use of aerobic exercise in pulmonary rehabilitation program, allows an improvement of motor skills, decreased muscle fatigue and deconditioning, reducing sedentary lifestyle; however, has little or no effect on the reduction of strength and atrophy muscle.

  11. AEROBIC EXERCISE IN PULMONARY REHABILITATION

    Directory of Open Access Journals (Sweden)

    Thiago Brasileiro de Vasconcelos

    2013-05-01

    Full Text Available The aim of this study was to conduct a literature review on the usefulness of aerobic exercise in pulmonary rehabilitation. This is an exploratory study of literature through the electronic databases Medline, Lilacs, Scielo, Pubmed and Google Scholar, published between 1996 and 2012, conducted during the period February to May 2012 with the following keywords: COPD, pulmonary rehabilitation, aerobic exercises, physical training, quality of life. The change in pulmonary function and dysfunction of skeletal muscles that result in exercise intolerance and reduced fitness and may cause social isolation, depression, anxiety and addiction. The training exercise is the most important component of the program of pulmonary rehabilitation where the aerobic training provides consistent results in clinical improvement in levels of exercise tolerance and decreased dyspnea generating more benefits to the body, reducing the chance of cardiovascular disease and improves quality and expectation of life. We demonstrated that the use of aerobic exercise in pulmonary rehabilitation program, allows an improvement of motor skills, decreased muscle fatigue and deconditioning, reducing sedentary lifestyle; however, has little or no effect on the reduction of strength and atrophy muscle.

  12. Quinones in aerobic and anaerobic mitochondria

    NARCIS (Netherlands)

    van der Klei, S.A.

    2009-01-01

    Ubiquinone (UQ), also known as coenzyme Q, is a ubiquitous quinone and is known to have several functions. One of these functions is electron carrier in the mitochondrial electron transport chain of aerobically functioning bacteria and eukaryotes. In contrast to this aerobically functioning quinone,

  13. Systems-level Proteomics of Two Ubiquitous Leaf Commensals Reveals Complementary Adaptive Traits for Phyllosphere Colonization.

    Science.gov (United States)

    Müller, Daniel B; Schubert, Olga T; Röst, Hannes; Aebersold, Ruedi; Vorholt, Julia A

    2016-10-01

    Plants are colonized by a diverse community of microorganisms, the plant microbiota, exhibiting a defined and conserved taxonomic structure. Niche separation based on spatial segregation and complementary adaptation strategies likely forms the basis for coexistence of the various microorganisms in the plant environment. To gain insights into organism-specific adaptations on a molecular level, we selected two exemplary community members of the core leaf microbiota and profiled their proteomes upon Arabidopsis phyllosphere colonization. The highly quantitative mass spectrometric technique SWATH MS was used and allowed for the analysis of over two thousand proteins spanning more than three orders of magnitude in abundance for each of the model strains. The data suggest that Sphingomonas melonis utilizes amino acids and hydrocarbon compounds during colonization of leaves whereas Methylobacterium extorquens relies on methanol metabolism in addition to oxalate metabolism, aerobic anoxygenic photosynthesis and alkanesulfonate utilization. Comparative genomic analyses indicates that utilization of oxalate and alkanesulfonates is widespread among leaf microbiota members whereas, aerobic anoxygenic photosynthesis is almost exclusively found in Methylobacteria. Despite the apparent niche separation between these two strains we also found a relatively small subset of proteins to be coregulated, indicating common mechanisms, underlying successful leaf colonization. Overall, our results reveal for two ubiquitous phyllosphere commensals species-specific adaptations to the host environment and provide evidence for niche separation within the plant microbiota. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Early colonization of thermal niches in a silica-depositing hot spring in central Tibet.

    Science.gov (United States)

    Lau, C Y; Aitchison, J C; Pointing, S B

    2008-03-01

    Thermophilic microbial mats dominated by the anoxygenic phototroph Roseiflexus castenholzii commonly develop around sinter-depositing geysers in the Daggyai Tso geothermal field of central Tibet. In this study we used morphological and molecular genetic techniques to reveal a diverse pioneer biofilm community including both archaea and bacteria involved in early colonization of such thermal niches at temperatures ranging from 46 to 77 degrees C. Sinter precipitation and biomineralization were evident at all locations, but the latter was selective between taxa and most evident on filamentous cells. Evidence for possible indirect biosignatures from biofilms overwhelmed by sinter deposition was found. Succession to a mature community appeared to relate to the growth rate for key taxa outpacing that of silicification within an optimum temperature range of 54-61 degrees C. The thin surface layer of silicification-resistant cyanobacteria that developed on the surface of mature mats may play a role in preventing biomineralization of the susceptible R. castenholzii beneath within these communities.

  15. Roseobacter-Like Bacteria in Red and Mediterranean Sea Aerobic Anoxygenic Photosynthetic Populations

    Czech Academy of Sciences Publication Activity Database

    Oz, A.; Sabehi, G.; Koblížek, Michal; Massana, R.; Béja, O.

    2005-01-01

    Roč. 71, č. 1 (2005), s. 344-353 ISSN 0099-2240 R&D Projects: GA ČR GP206/03/P079; GA MŠk LN00A141 Institutional research plan: CEZ:AV0Z5020903 Keywords : Roseobacter * photosynthetic population Subject RIV: EE - Microbiology, Virology Impact factor: 3.818, year: 2005

  16. Application of Kinect Technology in Blind Aerobics Learning

    Directory of Open Access Journals (Sweden)

    Hui Qu

    2017-12-01

    Full Text Available In order for blind people to learn aerobics more conveniently, we combined Kinect skeletal tracking technology with aerobics-assisted training to design a Kinect-based aerobics-assisted training system. Through the Kinect somatosensory camera, the feature extraction method and recognition algorithm of sign language are improved, and the sign language recognition system is realized. Sign language is translated through the sign language recognition system and expressed in understandable terms, providing a sound way of learning. The experimental results show that the system can automatically collect and recognize the aerobics movements. By comparing with the standard movements in the database, the system evaluates the posture of trainers from the perspectives of joint coordinates and joint angles, followed by the provision of movements contrast graphics and corresponding advice. Therefore, the system can effectively help the blind to learn aerobics.

  17. Toxic and inhibitory effects of trichloroethylene aerobic co-metabolism on phenol-grown aerobic granules.

    Science.gov (United States)

    Zhang, Yi; Tay, JooHwa

    2015-04-09

    Aerobic granule, a form of microbial aggregate, exhibits good potential in degrading toxic and recalcitrant substances. In this study, the inhibitory and toxic effects of trichloroethylene (TCE), a model compound for aerobic co-metabolism, on phenol-grown aerobic granules were systematically studied, using respiratory activities after exposure to TCE as indicators. High TCE concentration did not exert positive or negative effects on the subsequent endogenous respiration rate or phenol dependent specific oxygen utilization rate (SOUR), indicating the absence of solvent stress and induction effect on phenol-hydroxylase. Phenol-grown aerobic granules exhibited a unique response to TCE transformation product toxicity, that small amount of TCE transformation enhanced the subsequent phenol SOUR. Granules that had transformed between 1.3 and 3.7 mg TCE gSS(-1) showed at most 53% increase in the subsequent phenol SOUR, and only when the transformation exceeded 6.6 mg TCE gSS(-1) did the SOUR dropped below that of the control. This enhancing effect was found to sustain throughout several phenol dosages, and TCE transformation below the toxicity threshold also lessened the granules' sensitivity to higher phenol concentration. The unique toxic effect was possibly caused by the granule's compact structure as a protection barrier against the diffusive transformation product(s) of TCE co-metabolism. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. The chemical and mechanical differences between alginate-like exopolysaccharides isolated from aerobic flocculent sludge and aerobic granular sludge

    NARCIS (Netherlands)

    Lin, Y. M.; Sharma, P. K.; van Loosdrecht, M. C. M.

    2013-01-01

    This study aimed to investigate differences in the gel matrix of aerobic granular sludge and normal aerobic flocculent sludge. From both types of sludge that fed with the same municipal sewage, the functional gel-forming exopolysaccharides, alginate-like exopolysaccharides, were isolated. These two

  19. Development of Synechocystis sp. PCC 6803 as a Phototrophic Cell Factory

    Directory of Open Access Journals (Sweden)

    Fuzhong Zhang

    2013-08-01

    Full Text Available Cyanobacteria (blue-green algae play profound roles in ecology and biogeochemistry. One model cyanobacterial species is the unicellular cyanobacterium Synechocystis sp. PCC 6803. This species is highly amenable to genetic modification. Its genome has been sequenced and many systems biology and molecular biology tools are available to study this bacterium. Recently, researchers have put significant efforts into understanding and engineering this bacterium to produce chemicals and biofuels from sunlight and CO2. To demonstrate our perspective on the application of this cyanobacterium as a photosynthesis-based chassis, we summarize the recent research on Synechocystis 6803 by focusing on five topics: rate-limiting factors for cell cultivation; molecular tools for genetic modifications; high-throughput system biology for genome wide analysis; metabolic modeling for physiological prediction and rational metabolic engineering; and applications in producing diverse chemicals. We also discuss the particular challenges for systems analysis and engineering applications of this microorganism, including precise characterization of versatile cell metabolism, improvement of product rates and titers, bioprocess scale-up, and product recovery. Although much progress has been achieved in the development of Synechocystis 6803 as a phototrophic cell factory, the biotechnology for “Compounds from Synechocystis” is still significantly lagging behind those for heterotrophic microbes (e.g., Escherichia coli.

  20. Acclimation of aerobic-activated sludge degrading benzene derivatives and co-metabolic degradation activities of trichloroethylene by benzene derivative-grown aerobic sludge.

    Science.gov (United States)

    Wang, Shizong; Yang, Qi; Bai, Zhiyong; Wang, Shidong; Wang, Yeyao; Nowak, Karolina M

    2015-01-01

    The acclimation of aerobic-activated sludge for degradation of benzene derivatives was investigated in batch experiments. Phenol, benzoic acid, toluene, aniline and chlorobenzene were concurrently added to five different bioreactors which contained the aerobic-activated sludge. After the acclimation process ended, the acclimated phenol-, benzoic acid-, toluene-, aniline- and chlorobenzene-grown aerobic-activated sludge were used to explore the co-metabolic degradation activities of trichloroethylene (TCE). Monod equation was employed to simulate the kinetics of co-metabolic degradation of TCE by benzene derivative-grown sludge. At the end of experiments, the mixed microbial communities grown under different conditions were identified. The results showed that the acclimation periods of microorganisms for different benzene derivatives varied. The maximum degradation rates of TCE for phenol-, benzoic acid-, toluene-, aniline- and chlorobenzene-grown aerobic sludge were 0.020, 0.017, 0.016, 0.0089 and 0.0047 mg g SS(-1) h(-1), respectively. The kinetic of TCE degradation in the absence of benzene derivative followed Monod equation well. Also, eight phyla were observed in the acclimated benzene derivative-grown aerobic sludge. Each of benzene derivative-grown aerobic sludge had different microbial community composition. This study can hopefully add new knowledge to the area of TCE co-metabolic by mixed microbial communities, and further the understanding on the function and applicability of aerobic-activated sludge.

  1. Aerobic growth at nanomolar oxygen concentrations

    DEFF Research Database (Denmark)

    Stolper, Daniel Aaron; Revsbech, Niels Peter; Canfield, Donald Eugene

    2010-01-01

    that Escherichia coli K-12, chosen for its well-understood biochemistry, rapid growth rate, and low-oxygen-affinity terminal oxidase, grows at oxygen levels of ≤ 3 nM, two to three orders of magnitude lower than previously observed for aerobes. Our study expands both the environmental range and temporal history...... of aerobic organisms....

  2. Aerobic capacity and its correlates in patients with ankylosing spondylitis.

    Science.gov (United States)

    Hsieh, Lin-Fen; Wei, James Cheng-Chung; Lee, Hsin-Yi; Chuang, Chih-Cheng; Jiang, Jiunn-Song; Chang, Kae-Chwen

    2016-05-01

    To evaluate aerobic capacity in patients with ankylosing spondylitis (AS) and determine possible relationships between aerobic capacity, pulmonary function, and disease-related variables. Forty-two patients with AS and 42 healthy controls were recruited in the study. Descriptive data, disease-related variables (grip strength, lumbosacral mobility, occiput-to-wall distance, chest expansion, finger-to-floor distance, Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Global Score, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and hemoglobin), and chest and thoracic spine x-rays were collected in each patient with AS. All subjects took standard pulmonary function and exercise tolerance tests, and forced vital capacity (FVC) and aerobic capacity were recorded. Both aerobic capacity and FVC in patients with AS were significantly lower than those in normal subjects (P aerobic capacity. There was significant correlation between aerobic capacity, vital capacity, chest expansion, Schober's test, cervical range of motion, and BASFI in patients with AS. Neither aerobic capacity nor vital capacity correlated with disease duration, ESR, CRP, and hemoglobin. Significantly reduced aerobic capacity and FVC were observed in patients with AS, and there was significant correlation between aerobic capacity, vital capacity, chest expansion, and BASFI. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  3. Aerobic growth at nanomolar oxygen concentrations

    DEFF Research Database (Denmark)

    Stolper, Daniel; Revsbech, Niels Peter; Canfield, Donald Eugene

    2010-01-01

    that Escherichia coli K-12, chosen for its well-understood biochemistry, rapid growth rate, and low-oxygen-affinity terminal oxidase, grows at oxygen levels of ≤ 3 nM, two to three orders of magnitude lower than previously observed for aerobes. Our study expands both the environmental range and temporal history...... of aerobic organisms....

  4. Aerobic capacity related to cardiac size in young children

    DEFF Research Database (Denmark)

    Dencker, M; Wollmer, P; Karlsson, M

    2013-01-01

    Aerobic capacity, defined as peak oxygen uptake (VO2PEAK), is generally considered to be the best single marker for aerobic fitness. We assessed if VO2PEAK is related to different cardiac dimensions in healthy young children on a population base.......Aerobic capacity, defined as peak oxygen uptake (VO2PEAK), is generally considered to be the best single marker for aerobic fitness. We assessed if VO2PEAK is related to different cardiac dimensions in healthy young children on a population base....

  5. Differences between Female Subjects Practicing Pilates and Aerobics

    Directory of Open Access Journals (Sweden)

    Josipa Radas

    2017-10-01

    Full Text Available The aim of this study was to establish if there are differences in strength between female subjects who practice Pilates and aerobics. Research was conducted on a sample of two groups, each consisting of 28 subjects, with tests being push-ups, "hundred" and wall squat hold. Differences between groups have been established by T-test for independent samples. Research has shown certain differences between aerobics and Pilates programs. Subjects who practice aerobics scored better results in all tests than subjects who practice Pilates. It can be concluded that aerobics program is much better for development of these types of strength. However, because this is not a representative sample that cannot be claimed.

  6. Evaluation of single and joint toxic effects of diuron and its main metabolites on natural phototrophic biofilms using a pollution-induced community tolerance (PICT) approach.

    Science.gov (United States)

    Pesce, Stéphane; Lissalde, Sophie; Lavieille, Delphine; Margoum, Christelle; Mazzella, Nicolas; Roubeix, Vincent; Montuelle, Bernard

    2010-09-15

    This study assessed the single and joint acute toxicity of diuron and two of its metabolites (DCPMU and 3,4-DCA) on natural phototrophic biofilms using a PICT approach with photosynthesis bioassays. River biofilm communities were collected at three sampling stations exhibiting increasing concentrations of diuron, DCPMU and 3,4-DCA from upstream to downstream. Applied individually, the parent compound was more toxic than its metabolites, with DCPMU being more toxic than 3,4-DCA which only inhibited photosynthesis at very high concentrations (EC25 at about 5 mg/l). Sensitivity of biofilm communities to diuron and DCPMU decreased from upstream to downstream, revealing tolerance induction in contaminated sections of the river, as expected from the PICT concept. Nevertheless, PICT was not applicable for 3,4-DCA, which similarly affected upstream, intermediate and downstream biofilm communities. Chemical mixtures of diuron and DCPMU demonstrated additive effects whereas combinations with 3,4-DCA enhanced the observed effects. Our results reveal that the individual and combined presence of diuron and DCPMU in lotic ecosystems can have both short-term effects (as shown with bioassays) and long-term effects (as shown through the PICT approach) on phototrophic biofilms, whereas environmental concentrations of 3,4-DCA may not affect biofilm photosynthetic activity. 2010 Elsevier B.V. All rights reserved.

  7. Relationship between aerobic bacteria, salmonellae and Campylobacter on broiler carcasses.

    Science.gov (United States)

    Cason, J A; Bailey, J S; Stern, N J; Whittemore, A D; Cox, N A

    1997-07-01

    Broiler carcasses were removed from commercial processing lines immediately after defeathering, before chilling, and after chilling to determine whether any relationship exists between aerobic bacteria and the human enteropathogens salmonellae and Campylobacter. In two experiments, a whole carcass rinse procedure was used to sample 30 carcasses after defeathering, 90 carcasses before chilling, and 90 carcasses after chilling, for a total of 210 different carcasses. Aerobic bacteria and Campylobacter spp. were enumerated and the incidence of salmonellae was determined. Salmonellae and Campylobacter incidences were 20 and 94%, respectively, for all carcasses sampled. After picking, neither salmonellae-positive nor Campylobacter-positive carcasses had mean aerobic most probable number (MPN) values that were different from carcasses negative for those organisms. Immediately before chilling, aerobic and Campylobacter counts were 7.12 and 5.33 log10 cfu per carcass, respectively. Immersion chilling reduced aerobic counts by approximately 1.8 log and Campylobacter by 1.5 log, with no change in salmonellae-positive carcasses. There was no difference in aerobic or Campylobacter counts between carcasses that were positive or negative for salmonellae at any of the sampling locations, nor was any correlation found between levels of aerobic organisms and Campylobacter. Carcasses with aerobic counts above the mean or more than one standard deviation above the mean also failed to show any correlation. Discriminant analysis indicated error rates as high as 50% when numbers of aerobic bacteria were used to predict incidence of salmonellae or Campylobacter on individual carcasses. Aerobic bacteria are not suitable as index organisms for salmonellae or Campylobacter on broiler carcasses.

  8. The aerobic activity of metronidazole against anaerobic bacteria.

    Science.gov (United States)

    Dione, Niokhor; Khelaifia, Saber; Lagier, Jean-Christophe; Raoult, Didier

    2015-05-01

    Recently, the aerobic growth of strictly anaerobic bacteria was demonstrated using antioxidants. Metronidazole is frequently used to treat infections caused by anaerobic bacteria; however, to date its antibacterial activity was only tested in anaerobic conditions. Here we aerobically tested using antioxidants the in vitro activities of metronidazole, gentamicin, doxycycline and imipenem against 10 common anaerobic and aerobic bacteria. In vitro susceptibility testing was performed by the disk diffusion method, and minimum inhibitory concentrations (MICs) were determined by Etest. Aerobic culture of the bacteria was performed at 37°C using Schaedler agar medium supplemented with 1mg/mL ascorbic acid and 0.1mg/mL glutathione; the pH was adjusted to 7.2 by 10M KOH. Growth of anaerobic bacteria cultured aerobically using antioxidants was inhibited by metronidazole after 72h of incubation at 37°C, with a mean inhibition diameter of 37.76mm and an MIC of 1μg/mL; however, strains remained non-sensitive to gentamicin. No growth inhibition of aerobic bacteria was observed after 24h of incubation at 37°C with metronidazole; however, inhibition was observed with doxycycline and imipenem used as controls. These results indicate that bacterial sensitivity to metronidazole is not related to the oxygen tension but is a result of the sensitivity of the micro-organism. In future, both culture and antibiotic susceptibility testing of strictly anaerobic bacteria will be performed in an aerobic atmosphere using antioxidants in clinical microbiology laboratories. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  9. Purple Phototrophic Bacterium Enhances Stevioside Yield by Stevia rebaudiana Bertoni via Foliar Spray and Rhizosphere Irrigation

    Science.gov (United States)

    Wu, Jing; Wang, Yiming; Lin, Xiangui

    2013-01-01

    This study was conducted to compare the effects of foliar spray and rhizosphere irrigation with purple phototrophic bacteria (PPB) on growth and stevioside (ST) yield of Stevia. rebaudiana. The S. rebaudiana plants were treated by foliar spray, rhizosphere irrigation, and spray plus irrigation with PPB for 10 days, respectively. All treatments enhanced growth of S. rebaudiana, and the foliar method was more efficient than irrigation. Spraying combined with irrigation increased the ST yield plant -1 by 69.2% as compared to the control. The soil dehydrogenase activity, S. rebaudiana shoot biomass, chlorophyll content in new leaves, and soluble sugar in old leaves were affected significantly by S+I treatment, too. The PPB probably works in the rhizosphere by activating the metabolic activity of soil bacteria, and on leaves by excreting phytohormones or enhancing the activity of phyllosphere microorganisms. PMID:23825677

  10. The anaerobic phototrophic metabolism of 3-chlorobenzoate by Rhodopseudomonas palustris

    Energy Technology Data Exchange (ETDEWEB)

    Kamal, V S

    1992-10-09

    The degradation of chlorinated aromatic compounds by anaerobic bacteria is now known to be an important mechanism of bioremediation. In an experimental study, a mixed phototrophic culture was found to metabolize 3-chlorobenzoate in the presence of benzoate following adaptation on a benzoate and 3-chlorobenzoate medium for 7 weeks. The dominant bacterial isolate was identified as Rhodopseudomonas palustris. Radioisotopic studies showed [sup 14]C-3-chlorobenzoate was converted by the isolate to [sup 14]CO[sub 2] and cell biomass in the absence of oxygen and in the presence of a cosubstrate red light. Cyclohexane carboxylate was able to replace the cosubstrate, benzoate. The isolate also metabolized 3-chlorobenzoate in the presence of pimelic acid, sodium acetate, and sodium succinate; however, the metabolic rate was reduced. Gas chromatography mass spectrometry and high pressure liquid chromatography indicated the intracellular presence of 3-chlorobenzoate and benzoyl-CoA. Cell-free extracts produced benzoate and benzoyl-CoA. A probable route of 3-chlorobenzoate metabolism via dehalogenation followed by steps similar to the benzoate reductive ring fission pathway is suggested. Comparison of kinetic coefficients showed a higher affinity of the isolate for benzoate. Isolates from representative samples of various freshwater and wastewater ecosystems indicated widespread ecological distribution of R. palustris and the common occurrence of the 3-chlorobenzoate metabolic phenotype. R. palustris was found to grow in mixed anaerobic cultures and retained its 3-chlorobenzoate degradation property. 91 refs., 25 figs., 14 tabs.

  11. Effect of copper and lead on two consortia of phototrophic microorganisms and their capacity to sequester metals.

    Science.gov (United States)

    Burgos, A; Maldonado, J; De Los Rios, A; Solé, A; Esteve, I

    2013-09-15

    The roles of consortia of phototrophic microorganisms have been investigated in this paper to determine their potential role to tolerate or resist metals and to capture them from polluted cultures. With this purpose, two consortia of microorganisms: on one hand, Geitlerinema sp. DE2011 (Ge) and Scenedesmus sp. DE2009 (Sc) (both identified in this paper by molecular biology methods) isolated from Ebro Delta microbial mats, and on the other, Spirulina sp. PCC 6313 (Sp) and Chroococcus sp. PCC 9106 (Ch), from Pasteur culture collection were polluted with copper and lead. In order to analyze the ability of these consortia to tolerate and capture metals, copper and lead were selected, because both have been detected in Ebro Delta microbial mats. The tolerance-resistance to copper and lead for both consortia was determined in vivo and at cellular level by Confocal Laser Scanning Microscopy (CLSM-λscan function). The results obtained demonstrate that both consortia are highly tolerant-resistant to lead and that the limits between the copper concentration having cytotoxic effect and that having an essential effect are very close in these microorganisms. The capacity of both consortia to capture extra- and intracellular copper and lead was determined by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) respectively, coupled to an Energy Dispersive X-ray detector (EDX). The results showed that all the microorganisms assayed were able to capture copper extracellularly in the extrapolymeric substances, and lead extra- and intracellularly in polyphosphate inclusions. Moreover, the studied micro-organisms did not exert any inhibitory effect on each other's metal binding capacity. From the results obtained in this paper, it can be concluded that consortia of phototrophic microorganisms could play a very important role in biorepairing sediments polluted by metals, as a result of their ability to tolerate or resist high concentrations of metals and to

  12. Systematic analysis of adaptations in aerobic capacity and submaximal energy metabolism provides a unique insight into determinants of human aerobic performance

    DEFF Research Database (Denmark)

    Vollaard, Niels B J; Constantin-Teodosiu, Dimitru; Fredriksson, Katarina

    2009-01-01

    It has not been established which physiological processes contribute to endurance training-related changes (Delta) in aerobic performance. For example, the relationship between intramuscular metabolic responses at the intensity used during training and improved human functional capacity has...... not been examined in a longitudinal study. In the present study we hypothesized that improvements in aerobic capacity (Vo(2max)) and metabolic control would combine equally to explain enhanced aerobic performance. Twenty-four sedentary males (24 +/- 2 yr; 1.81 +/- 0.08 m; 76.6 +/- 11.3 kg) undertook...... unrelated to the change in aerobic performance. The maximal parameters DeltaVe(max) and DeltaVeq(max) (DeltaVe/Vo(2max)) accounted for 64% of the variance in DeltaVo(2max) (P

  13. The study of a pilot-scale aerobic/Fenton/anoxic/aerobic process system for the treatment of landfill leachate.

    Science.gov (United States)

    Hu, Wenyong; Zhou, Yu; Min, Xiaobo; Liu, Jingyi; Li, Xinyu; Luo, Lin; Zhang, Jiachao; Mao, Qiming; Chai, Liyuan; Zhou, YaoYu

    2017-06-29

    In this study, a combined aerobic-Fenton-anoxic/aerobic system was designed for the remediation of raw landfill leachate in a pilot-scale experiment. This system included (i) a granular sludge biological oxidation procedure that achieves the accumulation of nitrite nitrogen ([Formula: see text]) under aerobic conditions; (ii) a Fenton process that improves the biodegradability of the biotreated leachate and (iii) an activated sludge biological oxidation component under anoxic and aerobic conditions. Additionally, a shortcut nitrification and denitrification pathway was achieved. The effects of free ammonia, temperature and pH on nitrite accumulation were discussed. The change in the biochemical oxygen demand/chemical oxygen demand ratio of the effluent after shortcut nitrification was also analysed. The microbial community in the reactor were also investigated. The problem of the lack of carbon source in the denitrification process can be solved by the Fenton reagent method. Moreover, it was beneficial to achieving nitrogen removal as well as the more extensive removal of organic matter. The treatment strategy employed in this study exhibited good results and provided the potential practical application for treating landfill leachate.

  14. The Andersen aerobic fitness test

    DEFF Research Database (Denmark)

    Aadland, Eivind; Terum, Torkil; Mamen, Asgeir

    2014-01-01

    BACKGROUND: High aerobic fitness is consistently associated with a favorable metabolic risk profile in children. Direct measurement of peak oxygen consumption (VO2peak) is often not feasible, thus indirect tests such as the Andersen test are required in many settings. The present study seeks...... of agreement) were 26.7±125.2 m for test 2 vs. test 1 (pfit in the present sample; thus, we suggest a new equation: VO2peak = 23....... Researchers should be aware of the amount of noise in indirect tests that estimate aerobic fitness....

  15. Aerobic Microbial Respiration In Oceanic Oxygen Minimum Zones

    DEFF Research Database (Denmark)

    Kalvelage, Tim; Lavik, Gaute; Jensen, Marlene Mark

    2015-01-01

    Namibia and Peru. Experiments with additions of double-labelled oxygen revealed high aerobic activity in the upper OMZs, likely controlled by surface organic matter export. Consistently observed oxygen consumption in samples retrieved throughout the lower OMZs hints at efficient exploitation of vertically...... and laterally advected, oxygenated waters in this zone by aerobic microorganisms. In accordance, metagenomic and metatranscriptomic analyses identified genes encoding for aerobic terminal oxidases and demonstrated their expression by diverse microbial communities, even in virtually anoxic waters. Our results...

  16. Carbon isotope fractionation by thermophilic phototrophic sulfur bacteria: evidence for autotrophic growth in natural populations

    Science.gov (United States)

    Madigan, M. T.; Takigiku, R.; Lee, R. G.; Gest, H.; Hayes, J. M.

    1989-01-01

    Purple phototrophic bacteria of the genus Chromatium can grow as either photoautotrophs or photoheterotrophs. To determine the growth mode of the thermophilic Chromatium species, Chromatium tepidum, under in situ conditions, we have examined the carbon isotope fractionation patterns in laboratory cultures of this organism and in mats of C. tepidum which develop in sulfide thermal springs in Yellowstone National Park. Isotopic analysis (13C/12C) of total carbon, carotenoid pigments, and bacteriochlorophyll from photoautotrophically grown cultures of C. tepidum yielded 13C fractionation factors near -20%. Cells of C. tepidum grown on excess acetate, wherein synthesis of the Calvin cycle enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase ribulose bisphosphate carboxylase) was greatly repressed, were isotopically heavier, fractionation factors of ca. -7% being observed. Fractionation factors determined by isotopic analyses of cells and pigment fractions of natural populations of C. tepidum growing in three different sulfide thermal springs in Yellowstone National Park were approximately -20%, indicating that this purple sulfur bacterium grows as a photoautotroph in nature.

  17. Enhanced selection of micro-aerobic pentachlorophenol degrading granular sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Yuancai, E-mail: donkey1204@hotmail.com [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Chen, Yuancai, E-mail: chenyc@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Song, Wenzhe, E-mail: songwenzhe007@126.com [Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Hu, Yongyou, E-mail: ppyyhu@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China)

    2014-09-15

    Graphical abstract: In this work, an aerobic column reactor was placed before the USB to maintain micro-oxygen condition in the reactor and the micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L{sup −1}) was successfully obtained. PCP degradation by the micro-aerobic system was studied and the variance of microbial community was also discussed by using PCR-DGGE analysis. - Highlights: • Micro-aerobic granular sludge was cultivated in column-type combined reactors. • PCP biodegradation, VFA accumulation and biogas production were studied. • The function of Methanogenic archaeon in the system was investigated. • Fluctuation and diversity of microbial community were discussed by DGGE analysis. • The dominated microorganisms were identified by 16S rDNA sequences. - Abstract: Column-type combined reactors were designed to cultivate micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L{sup −1}) over 39-day experimental period. Micro-aerobic granular had both anaerobic activity (SMA: 2.34 mMCH{sub 4}/h g VSS) and aerobic activity (SOUR: 2.21 mMO{sub 2}/h g VSS). Metabolite analysis results revealed that PCP was sequentially dechlorinated to TCP, DCP, and eventually to MCP. Methanogens were not directly involved in the dechlorination of PCP, but might played a vital role in stabilizing the overall structure of the granule sludge. For Eubacteria, the Shannon Index (2.09 in inoculated granular sludge) increased both in micro-aerobic granular sludge (2.61) and PCP-degradation granular sludge (2.55). However, for Archaea, it decreased from 2.53 to 1.85 and 1.84, respectively. Although the Shannon Index demonstrated slight difference between micro-aerobic granular sludge and PCP-degradation granular sludge, the Principal Component Analysis (PCA) indicated obvious variance of the microbial composition, revealing significant effect of micro-aerobic

  18. Enhanced selection of micro-aerobic pentachlorophenol degrading granular sludge

    International Nuclear Information System (INIS)

    Lv, Yuancai; Chen, Yuancai; Song, Wenzhe; Hu, Yongyou

    2014-01-01

    Graphical abstract: In this work, an aerobic column reactor was placed before the USB to maintain micro-oxygen condition in the reactor and the micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L −1 ) was successfully obtained. PCP degradation by the micro-aerobic system was studied and the variance of microbial community was also discussed by using PCR-DGGE analysis. - Highlights: • Micro-aerobic granular sludge was cultivated in column-type combined reactors. • PCP biodegradation, VFA accumulation and biogas production were studied. • The function of Methanogenic archaeon in the system was investigated. • Fluctuation and diversity of microbial community were discussed by DGGE analysis. • The dominated microorganisms were identified by 16S rDNA sequences. - Abstract: Column-type combined reactors were designed to cultivate micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L −1 ) over 39-day experimental period. Micro-aerobic granular had both anaerobic activity (SMA: 2.34 mMCH 4 /h g VSS) and aerobic activity (SOUR: 2.21 mMO 2 /h g VSS). Metabolite analysis results revealed that PCP was sequentially dechlorinated to TCP, DCP, and eventually to MCP. Methanogens were not directly involved in the dechlorination of PCP, but might played a vital role in stabilizing the overall structure of the granule sludge. For Eubacteria, the Shannon Index (2.09 in inoculated granular sludge) increased both in micro-aerobic granular sludge (2.61) and PCP-degradation granular sludge (2.55). However, for Archaea, it decreased from 2.53 to 1.85 and 1.84, respectively. Although the Shannon Index demonstrated slight difference between micro-aerobic granular sludge and PCP-degradation granular sludge, the Principal Component Analysis (PCA) indicated obvious variance of the microbial composition, revealing significant effect of micro-aerobic condition and

  19. [Factors associated with low levels of aerobic fitness among adolescents].

    Science.gov (United States)

    Gonçalves, Eliane Cristina de Andrade; Silva, Diego Augusto Santos

    2016-06-01

    To evaluate the prevalence of low aerobic fitness levels and to analyze the association with sociodemographic factors, lifestyle and excess body fatness among adolescents of southern Brazil. The study included 879 adolescents aged 14 to 19 years the city of São José/SC, Brazil. The aerobic fitness was assessed by Canadian modified test of aerobic fitness. Sociodemographic variables (skin color, age, sex, study turn, economic level), sexual maturation and lifestyle (eating habits, screen time, physical activity, consumption of alcohol and tobacco) were assessed by a self-administered questionnaire. Excess body fatness was evaluated by sum of skinfolds triceps and subscapular. We used logistic regression to estimate odds ratios and 95% confidence intervals. Prevalence of low aerobic fitness level was 87.5%. The girls who spent two hours or more in front screen, consumed less than one glass of milk by day, did not smoke and had an excess of body fatness had a higher chance of having lower levels of aerobic fitness. White boys with low physical activity had had a higher chance of having lower levels of aerobic fitness. Eight out of ten adolescents were with low fitness levels aerobic. Modifiable lifestyle factors were associated with low levels of aerobic fitness. Interventions that emphasize behavior change are needed. Copyright © 2015 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

  20. Benefits of aerobic exercise after stroke.

    Science.gov (United States)

    Potempa, K; Braun, L T; Tinknell, T; Popovich, J

    1996-05-01

    The debilitating loss of function after a stroke has both primary and secondary effects on sensorimotor function. Primary effects include paresis, paralysis, spasticity, and sensory-perceptual dysfunction due to upper motor neuron damage. Secondary effects, contractures and disuse muscle atrophy, are also debilitating. This paper presents theoretical and empirical benefits of aerobic exercise after stroke, issues relevant to measuring peak capacity, exercise training protocols, and the clinical use of aerobic exercise in this patient population. A stroke, and resulting hemiparesis, produces physiological changes in muscle fibres and muscle metabolism during exercise. These changes, along with comorbid cardiovascular disease, must be considered when exercising stroke patients. While few studies have measured peak exercise capacity in hemiparetic populations, it has been consistently observed in these studies that stroke patients have a lower functional capacity than healthy populations. Hemiparetic patients have low peak exercise responses probably due to a reduced number of motor units available for recruitment during dynamic exercise, the reduced oxidative capacity of paretic muscle, and decreased overall endurance. Consequently, traditional methods to predict aerobic capacity are not appropriate for use with stroke patients. Endurance exercise training is increasingly recognised as an important component in rehabilitation. An average improvement in maximal oxygen consumption (VO2max) of 13.3% in stroke patients who participated in a 10-week aerobic exercise training programme has been reported compared with controls. This study underscored the potential benefits of aerobic exercise training in stroke patients. In this paper, advantages and disadvantages of exercise modalities are discussed in relation to stroke patients. Recommendations are presented to maximise physical performance and minimise potential cardiac risks during exercise.

  1. Biological phosphorus uptake under anoxic and aerobic conditions

    DEFF Research Database (Denmark)

    Kerrn-Jespersen, Jens Peter; Henze, Mogens

    1993-01-01

    Biological phosphorus removal was investigated under anoxic and aerobic conditions. Tests were made to establish whether phosphorus accumulating bacteria can take up phosphate under anoxic conditions and thus utilise nitrate as oxidant. Furthermore, it was tested how the amount of organic matter...... as oxidant. The phosphorus uptake was more rapid under aerobic conditions than under anoxic conditions. The explanation of this is that all phosphorus accumulating bacteria take up phosphate under aerobic conditions, whereas only part of the phosphorus accumulating bacteria take up phosphate under anoxic...

  2. Manganese and the Evolution of Photosynthesis

    Science.gov (United States)

    Fischer, Woodward W.; Hemp, James; Johnson, Jena E.

    2015-09-01

    Oxygenic photosynthesis is the most important bioenergetic event in the history of our planet—it evolved once within the Cyanobacteria, and remained largely unchanged as it was transferred to algae and plants via endosymbiosis. Manganese plays a fundamental role in this history because it lends the critical redox behavior of the water-oxidizing complex of photosystem II. Constraints from the photoassembly of the Mn-bearing water-oxidizing complex fuel the hypothesis that Mn(II) once played a key role as an electron donor for anoxygenic photosynthesis prior to the evolution of oxygenic photosynthesis. Here we review the growing body of geological and geochemical evidence from the Archean and Paleoproterozoic sedimentary records that supports this idea and demonstrates that the oxidative branch of the Mn cycle switched on prior to the rise of oxygen. This Mn-oxidizing phototrophy hypothesis also receives support from the biological record of extant phototrophs, and can be made more explicit by leveraging constraints from structural biology and biochemistry of photosystem II in Cyanobacteria. These observations highlight that water-splitting in photosystem II evolved independently from a homodimeric ancestral type II reaction center capable of high potential photosynthesis and Mn(II) oxidation, which is required by the presence of homologous redox-active tyrosines in the modern heterodimer. The ancestral homodimer reaction center also evolved a C-terminal extension that sterically precluded standard phototrophic electron donors like cytochrome c, cupredoxins, or high-potential iron-sulfur proteins, and could only complete direct oxidation of small molecules like Mn2+, and ultimately water.

  3. Activated Sludge and Aerobic Biofilm Reactors

    OpenAIRE

    Von Sperling, Marcos

    2007-01-01

    "Activated Sludge and Aerobic Biofilm Reactors is the fifth volume in the series Biological Wastewater Treatment. The first part of the book is devoted to the activated sludge process, covering the removal of organic matter, nitrogen and phosphorus.A detailed analysis of the biological reactor (aeration tank) and the final sedimentation tanks is provided. The second part of the book covers aerobic biofilm reactors, especially trickling filters, rotating biological contractors and submerged ae...

  4. introduction aerobic mesophilic bacteria associated with irish potato

    African Journals Online (AJOL)

    Ife, Osun State, Nigeria and were analysed for aerobic mesophilic bacterial load. The isolated aerobic ... Of significant note is the high multiple resistance pattern of Bacillus sp. strain B2 which showed ..... by chlorine dioxide. J. Food Science.

  5. Meta-analysis: aerobic exercise for the treatment of anxiety disorders.

    Science.gov (United States)

    Bartley, Christine A; Hay, Madeleine; Bloch, Michael H

    2013-08-01

    This meta-analysis investigates the efficacy of exercise as a treatment for DSM-IV diagnosed anxiety disorders. We searched PubMED and PsycINFO for randomized, controlled trials comparing the anxiolytic effects of aerobic exercise to other treatment conditions for DSM-IV defined anxiety disorders. Seven trials were included in the final analysis, totaling 407 subjects. The control conditions included non-aerobic exercise, waitlist/placebo, cognitive-behavioral therapy, psychoeducation and meditation. A fixed-effects model was used to calculate the standardized mean difference of change in anxiety rating scale scores of aerobic exercise compared to control conditions. Subgroup analyses were performed to examine the effects of (1) comparison condition; (2) whether comparison condition controlled for time spent exercising and (3) diagnostic indication. Aerobic exercise demonstrated no significant effect for the treatment of anxiety disorders (SMD=0.02 (95%CI: -0.20-0.24), z = 0.2, p = 0.85). There was significant heterogeneity between trials (χ(2) test for heterogeneity = 22.7, df = 6, p = 0.001). The reported effect size of aerobic exercise was highly influenced by the type of control condition. Trials utilizing waitlist/placebo controls and trials that did not control for exercise time reported large effects of aerobic exercise while other trials report no effect of aerobic exercise. Current evidence does not support the use of aerobic exercise as an effective treatment for anxiety disorders as compared to the control conditions. This remains true when controlling for length of exercise sessions and type of anxiety disorder. Future studies evaluating the efficacy of aerobic exercise should employ larger sample sizes and utilize comparison interventions that control for exercise time. Copyright © 2013. Published by Elsevier Inc.

  6. Reduced anaerobic and aerobic performance in children with primary ciliary dyskinesia.

    Science.gov (United States)

    Simsek, Senem; Inal-Ince, Deniz; Cakmak, Aslihan; Emiralioglu, Nagehan; Calik-Kutukcu, Ebru; Saglam, Melda; Vardar-Yagli, Naciye; Ozcelik, Hayriye Ugur; Sonbahar-Ulu, Hazal; Bozdemir-Ozel, Cemile; Kiper, Nural; Arikan, Hulya

    2018-05-01

    Primary ciliary dyskinesia (PCD) restricts lifestyle and increases morbidity. The aim of the study was to investigate anaerobic and aerobic performance in children with PCD and their healthy counterparts. Thirty-one children with PCD and 29 age- and sex-matched healthy subjects were studied. Pulmonary function, hand grip strength (HGS), quadriceps strength (QMS), physical activity, anaerobic capacity (muscle power sprint test), and aerobic performance (modified shuttle walk test (MSWT)) were determined. Pulmonary function, HGS, QMS, mean anaerobic power (MAP), and MSWT distance in PCD were significantly lower than those of healthy subjects (p aerobic performance is impaired in PCD from the early stages. Age determines anaerobic performance. Gender is the determinant of aerobic performance. Whether skeletal muscle characteristics and sex-related changes in body composition affect anaerobic and aerobic capacity in PCD children warrants further study. What is Known: • Exercise performance is determined by anaerobic and aerobic power. • Few studies have shown that PCD patients have lower aerobic performance which is associated with impaired lung function. What is New: • The present research indicated that both anaerobic and aerobic exercise capacity determined using field testing is impaired in PCD from the early stages. • Anaerobic capacity was found to be independently associated with age in PCD. Higher aerobic performance is independently associated with male gender.

  7. Modelling non-redox enzymes: Anaerobic and aerobic acetylene ...

    Indian Academy of Sciences (India)

    Administrator

    Modelling non-redox enzymes: Anaerobic and aerobic acetylene hydratase. SABYASACHI SARKAR. Department of Chemistry, Indian Institute of Technology, Kanpur 208 016,. India. Acetaldehyde is the first metabolite produced during acetylene degradation by bacteria either aerobically or anaerobically. Conversion of ...

  8. Aerobic exercises alleviate symptoms of fatigue related to ...

    African Journals Online (AJOL)

    Background: Non-insulin dependent diabetic patients frequently suffer from fatigue symptoms that result from chronic systemic inflammation. Aerobic exercise was proved to modulate ... in obese patients with type 2 diabetes. Keywords: Aerobic exercise, inflammatory cytokines, obesity, Type 2 diabetes, fatigue syndrome.

  9. Influence of aerobic fitness on vasoreactivity in young men.

    Science.gov (United States)

    Bell, Preston L; Kelley, Edward T; McCoy, Stephanie M; Credeur, Daniel P

    2017-10-01

    Previous work has demonstrated a direct relationship between aerobic fitness and vasodilatory function (i.e., flow-mediated dilation; FMD); however, the relation between aerobic fitness and vasoconstrictor responsiveness (i.e., low flow-mediated constriction; L-FMC), and the overall vasoactive range (FMD + L-FMC) is unclear. To test the hypothesis that L-FMC and the overall vasoactive range (FMD + L-FMC) will be related to aerobic fitness in young, healthy men. Twenty men (age: 23 ± 5 years) were recruited, and divided evenly into a higher (HF) vs. lower (LF) aerobic fitness group, quantified via YMCA cycle ergometry (VO 2 peak extrapolation), and a 3-min step test (1-min heart rate recovery). Duplex Doppler-ultrasound was used to assess brachial artery FMD and L-FMC. Estimated VO 2 peak (HF = 55 ± 10 vs. LF = 38 ± 5 mL/kg/min) and heart rate recovery (HF = 36 ± 10 vs. LF = 25 ± 8 beats) were greater in the HF group (P aerobic fitness in young, healthy men. Longitudinal or interventional studies are warranted to support causality, and to distinguish whether L-FMC is more sensitive to changes in aerobic fitness than FMD.

  10. Characterization and Optimization of Dual Anaerobic/Aerobic Biofilm Process

    National Research Council Canada - National Science Library

    Togna, A

    1997-01-01

    The purpose of this Phase I STTR effort was to develop and characterize a dual anaerobic/aerobic biofilm process that promotes anaerobic reductive dehalogenation and aerobic cometabolic biodegradation...

  11. Anaerobic and aerobic transformation of TNT

    Energy Technology Data Exchange (ETDEWEB)

    Kulpa, C.F. [Univ. of Notre Dame, IN (United States). Dept. of Biological Sciences; Boopathy, R.; Manning, J. [Argonne National Lab., IL (United States). Environmental Research Div.

    1996-12-31

    Most studies on the microbial metabolism of nitroaromatic compounds have used pure cultures of aerobic microorganisms. In many cases, attempts to degrade nitroaromatics under aerobic conditions by pure cultures result in no mineralization and only superficial modifications of the structure. However, mixed culture systems properly operated result in the transformation of 2,4,6-trinitrotoluene (TNT) and in some cases mineralization of TNT occurs. In this paper, the mixed culture system is described with emphasis on intermediates and the characteristics of the aerobic microbial process including the necessity for a co-substrate. The possibility of removing TNT under aerobic/anoxic conditions is described in detail. Another option for the biodegradation of TNT and nitroaromatics is under anaerobic, sulfate reducing conditions. In this instance, the nitroaromatic compounds undergo a series of reductions with the formation of amino compounds. TNT under sulfate reducing conditions is reduced to triaminotoluene presumably by the enzyme nitrite reductase, which is commonly found in many Desulfovibrio spp. The removal of nitro groups from TNT is achieved by a series of reductive reactions with the formation of ammonia and toluene by Desulfovibrio sp. (B strain). These metabolic processes could be applied to other nitroaromatic compounds like nitrobenzene, nitrobenzoic acids, nitrophenols, and aniline. The data supporting the anaerobic transformation of TNT under different growth condition are reviewed in this report.

  12. Graded Aerobic Treadmill Testing in Adolescent Traumatic Brain Injury Patients.

    Science.gov (United States)

    Cordingley, Dean M; Girardin, Richard; Morissette, Marc P; Reimer, Karen; Leiter, Jeff; Russell, Kelly; Ellis, Michael J

    2017-11-01

    To examine the safety and tolerability of clinical graded aerobic treadmill testing in recovering adolescent moderate and severe traumatic brain injury (TBI) patients referred to a multidisciplinary pediatric concussion program. We completed a retrospective case series of two moderate and five severe TBI patients (mean age, 17.3 years) who underwent initial Buffalo Concussion Treadmill Testing at a mean time of 71.6 days (range, 55-87) postinjury. Six patients completed one graded aerobic treadmill test each and one patient underwent initial and repeat testing. There were no complications. Five initial treadmill tests were completely tolerated and allowed an accurate assessment of exercise tolerance. Two initial tests were terminated early by the treatment team because of neurological and cardiorespiratory limitations. As a result of testing, two patients were cleared for aerobic exercise as tolerated and four patients were treated with individually tailored submaximal aerobic exercise programs resulting in subjective improvement in residual symptoms and/or exercise tolerance. Repeat treadmill testing in one patient performed after 1 month of treatment with submaximal aerobic exercise prescription was suggestive of improved exercise tolerance. One patient was able to tolerate aerobic exercise following surgery for posterior glottic stenosis. Preliminary results suggest that graded aerobic treadmill testing is a safe, well tolerated, and clinically useful tool to assess exercise tolerance in appropriately selected adolescent patients with TBI. Future prospective studies are needed to evaluate the effect of tailored submaximal aerobic exercise prescription on exercise tolerance and patient outcomes in recovering adolescent moderate and severe TBI patients.

  13. Aerobic granular biomass: a novel biomaterial for efficient uranium removal

    International Nuclear Information System (INIS)

    Nancharaiah, Y.V.; Joshi, H.M.; Mohan, T.V.K.; Venugopalan, V.P.; Narasimhan, S.V.

    2006-01-01

    Aerobic microbial granules, self-immobilized microbial consortia cultured in aerobically operated bioreactors, primarily consist of mixed species of bacteria ensconced in an extracellular polymeric matrix of their own creation. Such aerobically grown microbial granules have attracted considerable research interest in environmental biotechnology. In recent times, it has been demonstrated that the granules could be used for efficient degradation of recalcitrant organic compounds and for the treatment of a growing number of wastes. The objective of this study was to investigate whether aerobic granules could be used as novel biomass material for biosorption of uranium from aqueous solutions

  14. Genes, Genomes, and Assemblages of Modern Anoxygenic Photosynthetic Cyanobacteria as Proxies for Ancient Cyanobacteria

    Science.gov (United States)

    Grim, S. L.; Dick, G.

    2015-12-01

    Oxygenic photosynthetic (OP) cyanobacteria were responsible for the production of O2 during the Proterozoic. However, the extent and degree of oxygenation of the atmosphere and oceans varied for over 2 Ga after OP cyanobacteria first appeared in the geologic record. Cyanobacteria capable of anoxygenic photosynthesis (AP) may have altered the trajectory of oxygenation, yet the scope of their role in the Proterozoic is not well known. Modern cyanobacterial populations from Middle Island Sinkhole (MIS), Michigan and a handful of cultured cyanobacterial strains, are capable of OP and AP. With their metabolic versatility, these microbes may approximate ancient cyanobacterial assemblages that mediated Earth's oxygenation. To better characterize the taxonomic and genetic signatures of these modern AP/OP cyanobacteria, we sequenced 16S rRNA genes and conducted 'omics analyses on cultured strains, lab mesocosms, and MIS cyanobacterial mat samples collected over multiple years from May to September. Diversity in the MIS cyanobacterial mat is low, with one member of Oscillatoriales dominating at all times. However, Planktothrix members are more abundant in the cyanobacterial community in late summer and fall. The shift in cyanobacterial community composition may be linked to seasonally changing light intensity. In lab mesocosms of MIS microbial mat, we observed a shift in dominant cyanobacterial groups as well as the emergence of Chlorobium, bacteria that specialize in AP. These shifts in microbial community composition and metabolism are likely in response to changing environmental parameters such as the availability of light and sulfide. Further research is needed to understand the impacts of the changing photosynthetic community on oxygen production and the entire microbial consortium. Our study connects genes and genomes of AP cyanobacteria to their environment, and improves understanding of cyanobacterial metabolic strategies that may have shaped Earth's redox evolution.

  15. Cellular thiol levels and aerobic radiosensitization by BSO

    International Nuclear Information System (INIS)

    Varnes, M.E.; Biaglow, J.E.; Roizin-Towle, L.; Hall, E.J.

    1984-01-01

    It has been previously shown that pretreatment of A549 human lung carcinoma cells and V79 cells with BSO results in enhancement of the aerobic radiation response. The authors and others have found that addition of either N-acetylcysteine (NAC) or the radioprotector WR-2721 to BSO-treated cells, just prior to irradiation, results in a return to control levels of aerobic sensitivity. NAC and WR-2721 have no effect on the aerobic response of control cells. Reversal of the BSO effect appears unrelated to intracellular thiol levels, since neither NAC nor WR-2721 replenish NPSH within the time that the reversal of the radiation effect is observed. In addition, NAC and WR-2721 must be present during irradiation in order to reverse the BSO sensitization. The authors are continuing to investigate the phenomenon of BSO-induced aerobic sensitization and its reversal, with particular emphasis on the role of membrane thiols and pyridine nucleotide reducing species in radiation response

  16. Oxidase catalysis via aerobically generated hypervalent iodine intermediates

    Science.gov (United States)

    Maity, Asim; Hyun, Sung-Min; Powers, David C.

    2018-02-01

    The development of sustainable oxidation chemistry demands strategies to harness O2 as a terminal oxidant. Oxidase catalysis, in which O2 serves as a chemical oxidant without necessitating incorporation of oxygen into reaction products, would allow diverse substrate functionalization chemistry to be coupled to O2 reduction. Direct O2 utilization suffers from intrinsic challenges imposed by the triplet ground state of O2 and the disparate electron inventories of four-electron O2 reduction and two-electron substrate oxidation. Here, we generate hypervalent iodine reagents—a broadly useful class of selective two-electron oxidants—from O2. This is achieved by intercepting reactive intermediates of aldehyde autoxidation to aerobically generate hypervalent iodine reagents for a broad array of substrate oxidation reactions. The use of aryl iodides as mediators of aerobic oxidation underpins an oxidase catalysis platform that couples substrate oxidation directly to O2 reduction. We anticipate that aerobically generated hypervalent iodine reagents will expand the scope of aerobic oxidation chemistry in chemical synthesis.

  17. Aerobic exercise training for adults with fibromyalgia.

    Science.gov (United States)

    Bidonde, Julia; Busch, Angela J; Schachter, Candice L; Overend, Tom J; Kim, Soo Y; Góes, Suelen M; Boden, Catherine; Foulds, Heather Ja

    2017-06-21

    Exercise training is commonly recommended for individuals with fibromyalgia. This review is one of a series of reviews about exercise training for people with fibromyalgia that will replace the "Exercise for treating fibromyalgia syndrome" review first published in 2002. • To evaluate the benefits and harms of aerobic exercise training for adults with fibromyalgia• To assess the following specific comparisons ० Aerobic versus control conditions (eg, treatment as usual, wait list control, physical activity as usual) ० Aerobic versus aerobic interventions (eg, running vs brisk walking) ० Aerobic versus non-exercise interventions (eg, medications, education) We did not assess specific comparisons involving aerobic exercise versus other exercise interventions (eg, resistance exercise, aquatic exercise, flexibility exercise, mixed exercise). Other systematic reviews have examined or will examine these comparisons (Bidonde 2014; Busch 2013). We searched the Cochrane Library, MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Physiotherapy Evidence Database (PEDro), Thesis and Dissertation Abstracts, the Allied and Complementary Medicine Database (AMED), the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), and the ClinicalTrials.gov registry up to June 2016, unrestricted by language, and we reviewed the reference lists of retrieved trials to identify potentially relevant trials. We included randomized controlled trials (RCTs) in adults with a diagnosis of fibromyalgia that compared aerobic training interventions (dynamic physical activity that increases breathing and heart rate to submaximal levels for a prolonged period) versus no exercise or another intervention. Major outcomes were health-related quality of life (HRQL), pain intensity, stiffness, fatigue, physical function, withdrawals, and adverse events. Two review authors independently selected trials for inclusion, extracted

  18. Phototrophic hydrogen production from glucose by pure and co-cultures of Clostridium butyricum and Rhodobacter sphaeroides

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Herbert H.P.; Zhu, Heguang; Zhang, Tong [Centre for Environmental Engineering Research, Department of Civil Engineering, University of Hong Kong, Pokfulam Road, Hong Kong (China)

    2006-12-15

    Phototrophic hydrogen production from glucose by pure and co-cultures of Clostridium butyricum and Rhodobacter sphaeroides was studied in batch experiments. Results showed that in all batches hydrogen was produced after a lag phase of about 10h; pure culture of R. sphaeroides produced hydrogen at rates substantially lower than C. butyricum. In co-culture systems, R. sphaeroides even with cell populations 5.9 times higher still could not compete with C. butyricum for glucose. In co-culture systems, R. sphaeroides syntrophically interacted with C. butyricum, using the acetate and butyrate produced by the latter as substrate for hydrogen production. Hydrogen production was ceased in all batches when the pH was lowered to the level of pH 6.5, resulting from the accumulation of fatty acids. It was also demonstrated in this study that fluorescence in situ hybridization (FISH) was an effective means for the quantification of the relative abundance of individual bacteria in a co-culture system. (author)

  19. Lower limb loading during knee up in step aerobics: a pilot study

    Directory of Open Access Journals (Sweden)

    Błażkiewicz Michalina

    2016-11-01

    Full Text Available Study aim: Step aerobics is a form of aerobic power distinguished from other types of aerobic exercise by its use of an elevated platform. The purpose of this study was to examine how the aerobic exercise “knee up” affects kinematic and kinetic parameters and, above all, the length of the muscle contractions.

  20. Characterization, Modeling and Application of Aerobic Granular Sludge for Wastewater Treatment

    Science.gov (United States)

    Liu, Xian-Wei; Yu, Han-Qing; Ni, Bing-Jie; Sheng, Guo-Ping

    Recently extensive studies have been carried out to cultivate aerobic granular sludge worldwide, including in China. Aerobic granules, compared with conventional activated sludge flocs, are well known for their regular, dense, and strong microbial structure, good settling ability, high biomass retention, and great ability to withstand shock loadings. Studies have shown that the aerobic granules could be applied for the treatment of low- or high-strength wastewaters, simultaneous removal of organic carbon, nitrogen and phosphorus, and decomposition of toxic wastewaters. Thus, this new form of activate sludge, like anaerobic granular sludge, could be employed for the treatment of municipal and industrial wastewaters in near future. This chapter attempts to provide an up-to-date review on the definition, cultivation, characterization, modeling and application of aerobic granular sludge for biological wastewater treatment. This review outlines some important discoveries with regard to the factors affecting the formation of aerobic granular sludge, their physicochemical characteristics, as well as their microbial structure and diversity. It also summarizes the modeling of aerobic granule formation. Finally, this chapter highlights the applications of aerobic granulation technology in the biological wastewater treatment. It is concluded that the knowledge regarding aerobic granular sludge is far from complete. Although previous studies in this field have undoubtedly improved our understanding on aerobic granular sludge, it is clear that much remains to be learned about the process and that many unanswered questions still remain. One of the challenges appears to be the integration of the existing and growing scientific knowledge base with the observations and applications in practice, which this paper hopes to partially achieve.

  1. Inhibiting aerobic glycolysis suppresses renal interstitial fibroblast activation and renal fibrosis.

    Science.gov (United States)

    Ding, Hao; Jiang, Lei; Xu, Jing; Bai, Feng; Zhou, Yang; Yuan, Qi; Luo, Jing; Zen, Ke; Yang, Junwei

    2017-09-01

    Chronic kidney diseases generally lead to renal fibrosis. Despite great progress having been made in identifying molecular mediators of fibrosis, the mechanism that governs renal fibrosis remains unclear, and so far no effective therapeutic antifibrosis strategy is available. Here we demonstrated that a switch of metabolism from oxidative phosphorylation to aerobic glycolysis (Warburg effect) in renal fibroblasts was the primary feature of fibroblast activation during renal fibrosis and that suppressing renal fibroblast aerobic glycolysis could significantly reduce renal fibrosis. Both gene and protein assay showed that the expression of glycolysis enzymes was upregulated in mouse kidneys with unilateral ureter obstruction (UUO) surgery or in transforming growth factor-β1 (TGF-β1)-treated renal interstitial fibroblasts. Aerobic glycolysis flux, indicated by glucose uptake and lactate production, was increased in mouse kidney with UUO nephropathy or TGF-β1-treated renal interstitial fibroblasts and positively correlated with fibrosis process. In line with this, we found that increasing aerobic glycolysis can remarkably induce myofibroblast activation while aerobic glycolysis inhibitors shikonin and 2-deoxyglucose attenuate UUO-induced mouse renal fibrosis and TGF-β1-stimulated myofibroblast activation. Furthermore, mechanistic study indicated that shikonin inhibits renal aerobic glycolysis via reducing phosphorylation of pyruvate kinase type M2, a rate-limiting glycolytic enzyme associated with cell reliance on aerobic glycolysis. In conclusion, our findings demonstrate the critical role of aerobic glycolysis in renal fibrosis and support treatment with aerobic glycolysis inhibitors as a potential antifibrotic strategy. Copyright © 2017 the American Physiological Society.

  2. Aerobic Mesophilic Bacteria Associated With Irish Potato ( Solanum ...

    African Journals Online (AJOL)

    A total of 15 samples of spoilt Irish potatoes (Solanum tuberosum L.) were collected from five grocery shops in Ile-Ife, Osun State, Nigeria and were analysed for aerobic mesophilic bacterial load. The isolated aerobic mesophilic bacteria were phenotypically characterized by biochemical tests and their susceptibility to ...

  3. Effect of aerobic exercise training on cardiovascular parameters and ...

    African Journals Online (AJOL)

    Effect of aerobic exercise training on cardiovascular parameters and CD4 cell ... its associated cardiovascular risk still pose some consequences for health and ... Moderate intensity aerobic exercise is an effective complementary therapy in ...

  4. Does Aerobic Exercise Influence Intrinsic Brain Activity?

    DEFF Research Database (Denmark)

    Flodin, Pär; Jonasson, Lars S; Riklund, Katrin

    2017-01-01

    exercise group or an active control group. Both groups recieved supervised training, 3 days a week for 6 months. Multimodal brain imaging data was acquired before and after the intervention, including 10 min of resting state brain functional magnetic resonance imaging (rs-fMRI) and arterial spin labeling......Previous studies have indicated that aerobic exercise could reduce age related decline in cognition and brain functioning. Here we investigated the effects of aerobic exercise on intrinsic brain activity. Sixty sedentary healthy males and females (64-78 years) were randomized into either an aerobic...... group improved more. Contrary to our hypothesis, we did not observe any significant group by time interactions with regard to any measure of intrinsic activity. To further probe putative relationships between fitness and brain activity, we performed post hoc analyses disregarding group belongings...

  5. Catalytic aerobic oxidation of bio-renewable chemicals

    DEFF Research Database (Denmark)

    Gorbanev, Yury

    , EDS, XRF and other methods. Supported gold and ruthenium hydroxide catalyst systems were explored for the aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDA), a potential polymer building block for the plastic industry, or its dimethyl ester (FDMC). High product......-free conditions. Moreover, a detailed study on the performance and stability of the ruthenium hydroxide catalysts on magnesium-containing supports under reaction conditions was conducted. The aerobic oxidation of HMF to form another value-added chemical, 2,5-diformylfuran (DFF), was also investigated......Ox deposited on various metal oxides. Furthermore, this thesis presents the results of the catalytic aerobic oxidative degradation of higher alcohols over supported ruthenium hydroxide catalysts. A very efficient oxidative cleavage of vic-diols to form respective acids was also shown under examined conditions...

  6. Aerobic Digestion. Student Manual. Biological Treatment Process Control.

    Science.gov (United States)

    Klopping, Paul H.

    This manual contains the textual material for a single-lesson unit on aerobic sludge digestion. Topic areas addressed include: (1) theory of aerobic digestion; (2) system components; (3) performance factors; (4) indicators of stable operation; and (5) operational problems and their solutions. A list of objectives, glossary of key terms, and…

  7. Solophos fertilizer improved rice plant growth in aerobic soil

    OpenAIRE

    NIE, Lixiao; PENG, Shaobing; BOUMAN, Bas A.M.; HUANG, Jianliang; CUI, Kehui; VISPERAS, Romeo M.; PARK, Hong-Kyu

    2007-01-01

    Yield decline of continuous monocropping of aerobic rice is the major constraint to the wide adoption of aerobic rice technology. This study was conducted to determine if solophos fertilizer could be used to reverse the yield decline of this cropping system using pot and micro-plot experiments. The soil for the pot experiment was collected from a field where aerobic rice has been grown continuously for 11 seasons at the IRRI farm. Four rates (4, 6, 8, and 10gpot^) of solophos application were...

  8. Domestic wastewater treatment with purple phototrophic bacteria using a novel continuous photo anaerobic membrane bioreactor.

    Science.gov (United States)

    Hülsen, Tim; Barry, Edward M; Lu, Yang; Puyol, Daniel; Keller, Jürg; Batstone, Damien J

    2016-09-01

    A key future challenge of domestic wastewater treatment is nutrient recovery while still achieving acceptable discharge limits. Nutrient partitioning using purple phototrophic bacteria (PPB) has the potential to biologically concentrate nutrients through growth. This study evaluates the use of PPB in a continuous photo-anaerobic membrane bioreactor (PAnMBR) for simultaneous organics and nutrient removal from domestic wastewater. This process could continuously treat domestic wastewater to discharge limits (60% of PPB, though the PPB community was highly variable. The outcomes from the current work demonstrate the potential of PPB for continuous domestic (and possibly industrial) wastewater treatment and nutrient recovery. Technical challenges include the in situ COD supply in a continuous reactor system, as well as efficient light delivery. Addition of external (agricultural or fossil) derived organics is not financially nor environmentally justified, and carbon needs to be sourced internally from the biomass itself to enable this technology. Reduced energy consumption for lighting is technically feasible, and needs to be addressed as a key objective in scaleup. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Degradation of TCE using sequential anaerobic biofilm and aerobic immobilized bed reactor

    Science.gov (United States)

    Chapatwala, Kirit D.; Babu, G. R. V.; Baresi, Larry; Trunzo, Richard M.

    1995-01-01

    Bacteria capable of degrading trichloroethylene (TCE) were isolated from contaminated wastewaters and soil sites. The aerobic cultures were identified as Pseudomonas aeruginosa (four species) and Pseudomonas fluorescens. The optimal conditions for the growth of aerobic cultures were determined. The minimal inhibitory concentration values of TCE for Pseudomonas sps. were also determined. The aerobic cells were immobilized in calcium alginate in the form of beads. Degradation of TCE by the anaerobic and dichloroethylene (DCE) by aerobic cultures was studied using dual reactors - anaerobic biofilm and aerobic immobilized bed reactor. The minimal mineral salt (MMS) medium saturated with TCE was pumped at the rate of 1 ml per hour into the anaerobic reactor. The MMS medium saturated with DCE and supplemented with xylenes and toluene (3 ppm each) was pumped at the rate of 1 ml per hour into the fluidized air-uplift-type reactor containing the immobilized aerobic cells. The concentrations of TCE and DCE and the metabolites formed during their degradation by the anaerobic and aerobic cultures were monitored by GC. The preliminary study suggests that the anaerobic and aerobic cultures of our isolates can degrade TCE and DCE.

  10. Complete genome sequence of Rhodospirillum rubrum type strain (S1).

    Science.gov (United States)

    Munk, A Christine; Copeland, Alex; Lucas, Susan; Lapidus, Alla; Del Rio, Tijana Glavina; Barry, Kerrie; Detter, John C; Hammon, Nancy; Israni, Sanjay; Pitluck, Sam; Brettin, Thomas; Bruce, David; Han, Cliff; Tapia, Roxanne; Gilna, Paul; Schmutz, Jeremy; Larimer, Frank; Land, Miriam; Kyrpides, Nikos C; Mavromatis, Konstantinos; Richardson, Paul; Rohde, Manfred; Göker, Markus; Klenk, Hans-Peter; Zhang, Yaoping; Roberts, Gary P; Reslewic, Susan; Schwartz, David C

    2011-07-01

    Rhodospirillum rubrum (Esmarch 1887) Molisch 1907 is the type species of the genus Rhodospirillum, which is the type genus of the family Rhodospirillaceae in the class Alphaproteobacteria. The species is of special interest because it is an anoxygenic phototroph that produces extracellular elemental sulfur (instead of oxygen) while harvesting light. It contains one of the most simple photosynthetic systems currently known, lacking light harvesting complex 2. Strain S1(T) can grow on carbon monoxide as sole energy source. With currently over 1,750 PubMed entries, R. rubrum is one of the most intensively studied microbial species, in particular for physiological and genetic studies. Next to R. centenum strain SW, the genome sequence of strain S1(T) is only the second genome of a member of the genus Rhodospirillum to be published, but the first type strain genome from the genus. The 4,352,825 bp long chromosome and 53,732 bp plasmid with a total of 3,850 protein-coding and 83 RNA genes were sequenced as part of the DOE Joint Genome Institute Program DOEM 2002.

  11. Pigment organization in the photosynthetic apparatus of Roseiflexus castenholzii.

    Science.gov (United States)

    Collins, Aaron M; Xin, Yueyong; Blankenship, Robert E

    2009-08-01

    The light-harvesting-reaction center (LHRC) complex from the chlorosome-lacking filamentous anoxygenic phototroph (FAP), Roseiflexus castenholzii (R. castenholzii) was purified and characterized for overall pigment organization. The LHRC is a single complex that is comprised of light harvesting (LH) and reaction center (RC) polypeptides as well as an attached c-type cytochrome. The dominant carotenoid found in the LHRC is keto-gamma-carotene, which transfers excitation to the long wavelength antenna band with 35% efficiency. Linear dichroism and fluorescence polarization measurements indicate that the long wavelength antenna pigments absorbing around 880 nm are perpendicular to the membrane plane, with the corresponding Q(y) transition dipoles in the plane of the membrane. The antenna pigments absorbing around 800 nm, as well as the bound carotenoid, are oriented at a large angle with respect to the membrane. The antenna pigments spectroscopically resemble the well-studied LH2 complex from purple bacteria, however the close association with the RC makes the light harvesting component of this complex functionally more like LH1.

  12. Nitrate-Dependent Degradation of Acetone by Alicycliphilus and Paracoccus Strains and Comparison of Acetone Carboxylase Enzymes ▿

    Science.gov (United States)

    Dullius, Carlos Henrique; Chen, Ching-Yuan; Schink, Bernhard

    2011-01-01

    A novel acetone-degrading, nitrate-reducing bacterium, strain KN Bun08, was isolated from an enrichment culture with butanone and nitrate as the sole sources of carbon and energy. The cells were motile short rods, 0.5 to 1 by 1 to 2 μm in size, which gave Gram-positive staining results in the exponential growth phase and Gram-negative staining results in the stationary-growth phase. Based on 16S rRNA gene sequence analysis, the isolate was assigned to the genus Alicycliphilus. Besides butanone and acetone, the strain used numerous fatty acids as substrates. An ATP-dependent acetone-carboxylating enzyme was enriched from cell extracts of this bacterium and of Alicycliphilus denitrificans K601T by two subsequent DEAE Sepharose column procedures. For comparison, acetone carboxylases were enriched from two additional nitrate-reducing bacterial species, Paracoccus denitrificans and P. pantotrophus. The products of the carboxylase reaction were acetoacetate and AMP rather than ADP. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of cell extracts and of the various enzyme preparations revealed bands corresponding to molecular masses of 85, 78, and 20 kDa, suggesting similarities to the acetone carboxylase enzymes described in detail for the aerobic bacterium Xanthobacter autotrophicus strain Py2 (85.3, 78.3, and 19.6 kDa) and the phototrophic bacterium Rhodobacter capsulatus. Protein bands were excised and compared by mass spectrometry with those of acetone carboxylases of aerobic bacteria. The results document the finding that the nitrate-reducing bacteria studied here use acetone-carboxylating enzymes similar to those of aerobic and phototrophic bacteria. PMID:21841031

  13. Aerobic decolourization of two reactive azo dyes under varying ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-01

    Feb 1, 2010 ... Azo dyes generally resist aerobic microbial degra- dation, only organisms with specialized azo dye reducing enzymes were found to degrade azo dyes under fully aerobic ... textile mill, in sterile plastic bottles. Isolation of ...

  14. Aerobic microbial enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Torsvik, T. [Univ. of Bergen (Norway); Gilje, E.; Sunde, E.

    1995-12-31

    In aerobic MEOR, the ability of oil-degrading bacteria to mobilize oil is used to increase oil recovery. In this process, oxygen and mineral nutrients are injected into the oil reservoir in order to stimulate growth of aerobic oil-degrading bacteria in the reservoir. Experiments carried out in a model sandstone with stock tank oil and bacteria isolated from offshore wells showed that residual oil saturation was lowered from 27% to 3%. The process was time dependent, not pore volume dependent. During MEOR flooding, the relative permeability of water was lowered. Oxygen and active bacteria were needed for the process to take place. Maximum efficiency was reached at low oxygen concentrations, approximately 1 mg O{sub 2}/liter.

  15. Aerobic training alone or combined with strength training affects fitness in elderly

    DEFF Research Database (Denmark)

    Burich, Rasmus; Teljigović, Sanel; Boyle, Eleanor

    2015-01-01

    PURPOSE: To investigate if combined strength and aerobic training can enhance aerobic capacity in the elderly to a similar extent as aerobic training alone when training duration is matched. METHODS: Elderly men and women (age 63.2 ± 4.7) were randomized into two intervention groups: an aerobic...... on the general health dimension on the SF-36 health survey improved more than AG's score. CONCLUSION: Elderly can substitute a part of their aerobic training with strength training and still improve VO2max to a clinically significant degree when strength training is performed with large muscle groups...

  16. Optimization of phototrophic hydrogen production by Rhodopseudomonas palustris PBUM001 via statistical experimental design

    Energy Technology Data Exchange (ETDEWEB)

    Jamil, Zadariana [Department of Civil Engineering, Faculty of Engineering, University of Malaya (Malaysia); Faculty of Civil Engineering, Technology University of MARA (Malaysia); Mohamad Annuar, Mohamad Suffian; Vikineswary, S. [Institute of Biological Sciences, University of Malaya (Malaysia); Ibrahim, Shaliza [Department of Civil Engineering, Faculty of Engineering, University of Malaya (Malaysia)

    2009-09-15

    Phototrophic hydrogen production by indigenous purple non-sulfur bacteria, Rhodopseudomonas palustris PBUM001 from palm oil mill effluent (POME) was optimized using response surface methodology (RSM). The process parameters studied include inoculum sizes (% v/v), POME concentration (% v/v), light intensity (klux), agitation (rpm) and pH. The experimental data on cumulative hydrogen production and COD reduction were fitted into a quadratic polynomial model using response surface regression analysis. The path to optimal process conditions was determined by analyzing response surface three-dimensional surface plot and contour plot. Statistical analysis on experimental data collected following Box-Behnken design showed that 100% (v/v) POME concentration, 10% (v/v) inoculum size, light intensity at 4.0 klux, agitation rate at 250 rpm and pH of 6 were the best conditions. The maximum predicted cumulative hydrogen production and COD reduction obtained under these conditions was 1.05 ml H{sub 2}/ml POME and 31.71% respectively. Subsequent verification experiments at optimal process values gave the maximum yield of cumulative hydrogen at 0.66 {+-} 0.07 ml H{sub 2}/ml POME and COD reduction at 30.54 {+-} 9.85%. (author)

  17. Strength training and aerobic exercise training for muscle disease.

    NARCIS (Netherlands)

    Voet, N.B.M.; Kooi, E.L. van der; Riphagen, I.I.; Lindeman, E.; Engelen, B.G.M. van; Geurts, A.C.H.

    2010-01-01

    BACKGROUND: Strength training or aerobic exercise programmes might optimise muscle and cardiorespiratory function and prevent additional disuse atrophy and deconditioning in people with a muscle disease. OBJECTIVES: To examine the safety and efficacy of strength training and aerobic exercise

  18. The removal of N and P in aerobic and anoxic-aerobic digestion of ...

    African Journals Online (AJOL)

    When this sludge is thickened to 3–6% total suspended solids (TSS) and digested. (aerobic or .... wastewater treatment plant (Cape Town, South Africa) in 2. 000 ℓ batches ...... MSc thesis, University of Cape Town, Cape. Town, South Africa.

  19. State of the art of aerobic granulation in continuous flow bioreactors.

    Science.gov (United States)

    Kent, Timothy R; Bott, Charles B; Wang, Zhi-Wu

    In the wake of the success of aerobic granulation in sequential batch reactors (SBRs) for treating wastewater, attention is beginning to turn to continuous flow applications. This is a necessary step given the advantages of continuous flow treatment processes and the fact that the majority of full-scale wastewater treatment plants across the world are operated with aeration tanks and clarifiers in a continuous flow mode. As in SBRs, applying a selection pressure, based on differences in either settling velocity or the size of the biomass, is essential for successful granulation in continuous flow reactors (CFRs). CFRs employed for aerobic granulation come in multiple configurations, each with their own means of achieving such a selection pressure. Other factors, such as bioaugmentation and hydraulic shear force, also contribute to aerobic granulation to some extent. Besides the formation of aerobic granules, long-term stability of aerobic granules is also a critical issue to be addressed. Inorganic precipitation, special inocula, and various operational optimization strategies have been used to improve granule long-term structural integrity. Accumulated studies reviewed in this work demonstrate that aerobic granulation in CFRs is capable of removing a wide spectrum of contaminants and achieving properties generally comparable to those in SBRs. Despite the notable research progress made toward successful aerobic granulation in lab-scale CFRs, to the best of our knowledge, there are only three full-scale tests of the technique, two being seeded with anammox-supported aerobic granules and the other with conventional aerobic granules; two other process alternatives are currently in development. Application of settling- or size-based selection pressures and feast/famine conditions are especially difficult to implement to these and similar mainstream systems. Future research efforts needs to be focused on the optimization of the granule-to-floc ratio, enhancement of

  20. Aerobic Physical Activity and the Leadership of Principals

    Science.gov (United States)

    Kiser, Kari

    2016-01-01

    The purpose of this study was to explore if there was a connection between regular aerobic physical activity and the stress and energy levels of principals as they reported it. To begin the research, the current aerobic physical activity level of principals was discovered. Additionally, the energy and stress levels of the principals who do engage…

  1. Survey the effect of aerobic exercise on aerobic capacity in patients with coronary artery disease (cad)

    International Nuclear Information System (INIS)

    Kalyani, M. N.; Ebadi, A.

    2007-01-01

    Increased aerobic exercise capacity appears to reduce both all-cause mortality and cardiovascular disease mortality. Physical exercise to improve maximal oxygen consumption (VO/sub 2max/) is thus strongly recommended, however evidence regarding the most efficient training intensity for patients with coronary artery disease (CAD) is still lacking. The purpose of this randomized study was to assess the effects of aerobic exercise for increasing VO/sub 2max/ in stable CAD-patients. Thirty stable CAD-patients were randomized to supervised walking 30 min three times a week for 10 weeks. Before and after training VO/sub 2max/ was predicted from Bruce treadmill test. Before training VO/sub 2max/ was 35.2+-4.32 ml/kg/min and after training the mean VO/sub 2max/ was 43.1+-3.4 ml/kg/min. This difference was significant (p<0.05). Aerobic exercise is effective for increasing VO/sub 2max/ in stable CAD-patients. As VO/sub 2max/ seems to reflect a continuum between health and cardiovascular disease and death, the present data may be useful in designing effective training programmes for improved health in the future. (author)

  2. Assessment of aerobic and respiratory growth in the Lactobacillus casei group.

    Directory of Open Access Journals (Sweden)

    Teresa Zotta

    Full Text Available One hundred eighty four strains belonging to the species Lactobacillus casei, L. paracasei and L. rhamnosus were screened for their ability to grow under aerobic conditions, in media containing heme and menaquinone and/or compounds generating reactive oxygen species (ROS, in order to identify respiratory and oxygen-tolerant phenotypes. Most strains were able to cope with aerobic conditions and for many strains aerobic growth and heme or heme/menaquinone supplementation increased biomass production compared to anaerobic cultivation. Only four L. casei strains showed a catalase-like activity under anaerobic, aerobic and respiratory conditions and were able to survive in presence of H2O2 (1 mM. Almost all L. casei and L. paracasei strains tolerated menadione (0.2 mM and most tolerated pyrogallol (50 mM, while L. rhamnosus was usually resistant only to the latter compound. This is the first study in which an extensive screening of oxygen and oxidative stress tolerance of members of the L. casei group has been carried out. Results allowed the selection of strains showing the typical traits of aerobic and respiratory metabolism (increased pH and biomass under aerobic or respiratory conditions and unique oxidative stress response properties. Aerobic growth and respiration may confer technological and physiological advantages in the L. casei group and oxygen-tolerant phenotypes could be exploited in several food industry applications.

  3. Assessment of Aerobic and Respiratory Growth in the Lactobacillus casei Group

    Science.gov (United States)

    Zotta, Teresa; Ricciardi, Annamaria; Ianniello, Rocco G.; Parente, Eugenio; Reale, Anna; Rossi, Franca; Iacumin, Lucilla; Comi, Giuseppe; Coppola, Raffaele

    2014-01-01

    One hundred eighty four strains belonging to the species Lactobacillus casei, L. paracasei and L. rhamnosus were screened for their ability to grow under aerobic conditions, in media containing heme and menaquinone and/or compounds generating reactive oxygen species (ROS), in order to identify respiratory and oxygen-tolerant phenotypes. Most strains were able to cope with aerobic conditions and for many strains aerobic growth and heme or heme/menaquinone supplementation increased biomass production compared to anaerobic cultivation. Only four L. casei strains showed a catalase-like activity under anaerobic, aerobic and respiratory conditions and were able to survive in presence of H2O2 (1 mM). Almost all L. casei and L. paracasei strains tolerated menadione (0.2 mM) and most tolerated pyrogallol (50 mM), while L. rhamnosus was usually resistant only to the latter compound. This is the first study in which an extensive screening of oxygen and oxidative stress tolerance of members of the L. casei group has been carried out. Results allowed the selection of strains showing the typical traits of aerobic and respiratory metabolism (increased pH and biomass under aerobic or respiratory conditions) and unique oxidative stress response properties. Aerobic growth and respiration may confer technological and physiological advantages in the L. casei group and oxygen-tolerant phenotypes could be exploited in several food industry applications. PMID:24918811

  4. Concurrent aerobic plus resistance exercise versus aerobic exercise alone to improve health outcomes in paediatric obesity: a systematic review and meta-analysis.

    Science.gov (United States)

    García-Hermoso, Antonio; Ramírez-Vélez, Robinson; Ramírez-Campillo, Rodrigo; Peterson, Mark D; Martínez-Vizcaíno, Vicente

    2018-02-01

    To determine if the combination of aerobic and resistance exercise is superior to aerobic exercise alone for the health of obese children and adolescents. Systematic review with meta-analysis. Computerised search of 3 databases (MEDLINE, EMBASE, and Cochrane Controlled Trials Registry). Studies that compared the effect of supervised concurrent exercise versus aerobic exercise interventions, with anthropometric and metabolic outcomes in paediatric obesity (6-18 years old). The mean differences (MD) of the parameters from preintervention to postintervention between groups were pooled using a random-effects model. 12 trials with 555 youths were included in the meta-analysis. Compared with aerobic exercise alone, concurrent exercise resulted in greater reductions in body mass (MD=-2.28 kg), fat mass (MD=-3.49%; and MD=-4.34 kg) and low-density lipoprotein cholesterol (MD=-10.20 mg/dL); as well as greater increases in lean body mass (MD=2.20 kg) and adiponectin level (MD=2.59 μg/mL). Differences were larger for longer term programmes (>24 weeks). Concurrent aerobic plus resistance exercise improves body composition, metabolic profiles, and inflammatory state in the obese paediatric population. CRD42016039807. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  5. Developing selection protocols for weed competitiveness in aerobic rice

    NARCIS (Netherlands)

    Zhao, D.L.; Atlin, G.N.; Bastiaans, L.; Spiertz, J.H.J.

    2006-01-01

    Aerobic rice production systems, wherein rice is dry-sown in non-puddled soil and grown as an upland crop, offer large water savings but are subject to severe weed infestation. Weed-competitive cultivars will be critical to the adoption of aerobic rice production by farmers. Breeding

  6. Intrinsic aerobic capacity sets a divide for aging and longevity.

    Science.gov (United States)

    Koch, Lauren Gerard; Kemi, Ole J; Qi, Nathan; Leng, Sean X; Bijma, Piter; Gilligan, Lori J; Wilkinson, John E; Wisløff, Helene; Høydal, Morten A; Rolim, Natale; Abadir, Peter M; van Grevenhof, Elizabeth M; Smith, Godfrey L; Burant, Charles F; Ellingsen, Oyvind; Britton, Steven L; Wisløff, Ulrik

    2011-10-28

    Low aerobic exercise capacity is a powerful predictor of premature morbidity and mortality for healthy adults as well as those with cardiovascular disease. For aged populations, poor performance on treadmill or extended walking tests indicates closer proximity to future health declines. Together, these findings suggest a fundamental connection between aerobic capacity and longevity. Through artificial selective breeding, we developed an animal model system to prospectively test the association between aerobic exercise capacity and survivability (aerobic hypothesis). Laboratory rats of widely diverse genetic backgrounds (N:NIH stock) were selectively bred for low or high intrinsic (inborn) treadmill running capacity. Cohorts of male and female rats from generations 14, 15, and 17 of selection were followed for survivability and assessed for age-related declines in cardiovascular fitness including maximal oxygen uptake (VO(2max)), myocardial function, endurance performance, and change in body mass. Median lifespan for low exercise capacity rats was 28% to 45% shorter than high capacity rats (hazard ratio, 0.06; PPhysical activity levels, energy expenditure (Vo(2)), and lean body mass were all better sustained with age in rats bred for high aerobic capacity. These data obtained from a contrasting heterogeneous model system provide strong evidence that genetic segregation for aerobic exercise capacity can be linked with longevity and are useful for deeper mechanistic exploration of aging.

  7. Watershed-Induced Limnological and Microbial Status in Two Oligotrophic Andean Lakes Exposed to the Same Climatic Scenario

    Directory of Open Access Journals (Sweden)

    Alex Echeverría-Vega

    2018-03-01

    Full Text Available Laguna Negra and Lo Encañado are two oligotrophic Andean lakes forming part of the system fed by meltwater from distinct glacial tongues of the Echaurren glacier in central Chile, which is in a recession period. The recent increase in temperature and decline in precipitation have led to an increase of glacial meltwater and sediments entering these lakes. Although the lacustrine systems are also hydrogeologically connected, the limnology of the lakes is strongly controlled by the surface processes related to the respective sub-watersheds and hydrology. Watershed characteristics (area and length, slope, lithology, resistance to erosion, among others affect the chemical and physical characteristics of both lakes (e.g., nutrient concentration and turbidity. We studied physical and chemical variables and performed 16S rRNA amplicon sequencing to determine the specific microbial signature of the lakes. The transparency, temperature, turbidity and concentrations of chlorophyll-a, dissolved organic matter, nutrients and the total number of cells, revealed the different status of both lakes at the time of sampling. The predominant bacterial groups in both lakes were Proteobacteria, Verrucomicrobia, and Bacteroidetes. Interestingly, the contribution of phototrophs was significantly higher in LN compared to LE (13 and 4% respectively and the major fraction corresponded to Anoxygenic Phototrophs (AP represented by Chloroflexi, Alpha, and Betaproteobacteria. Multivariate analyses showed that the nutrient levels and the light availability of both lakes, which finally depend on the hydrological characteristics of the respective watersheds, explain the differential community composition/function. The abundance of a diverse photoheterotrophic bacterioplankton community suggests that the ability to utilize solar energy along with organic and inorganic substrates is a key function in these oligotrophic mountain lakes.

  8. Metagenomic Study of Iron Homeostasis in Iron Depositing Hot Spring Cyanobacterial Community

    Science.gov (United States)

    Brown, I.; Franklin H.; Tringe, S. G.; Klatt, C. G.; Bryant, D. A.; Sarkisova, S. A.; Guevara, M.

    2010-01-01

    Introduction: It is not clear how an iron-rich thermal hydrosphere could be hospitable to cyanobacteria, since reduced iron appears to stimulate oxidative stress in all domains of life and particularly in oxygenic phototrophs. Therefore, metagenomic study of cyanobacterial community in iron-depositing hot springs may help elucidate how oxygenic prokaryotes can withstand the extremely high concentrations of reactive oxygen species (ROS) produced by interaction between environmental Fe2+ and O2. Method: Anchor proteins from various species of cyanobacteria and some anoxygenic phototrophs were selected on the basis of their hypothetical role in Fe homeostasis and the suppression of oxidative stress and were BLASTed against the metagenomes of iron-depositing Chocolate Pots and freshwater Mushroom hot springs. Results: BLASTing proteins hypothesized to be involved in Fe homeostasis against the microbiomes from the two springs revealed that iron-depositing hot spring has a greater abundance of defensive proteins such as bacterioferritin comigratory protein (Bcp) and DNA-binding Ferritin like protein (Dps) than a fresh-water hot spring. One may speculate that the abundance of Bcp and Dps in an iron-depositing hot spring is connected to the need to suppress oxidative stress in bacteria inhabiting environments with high Fe2+ concnetration. In both springs, Bcp and Dps are concentrated within the cyanobacterial fractions of the microbial community (regardless of abundance). Fe3+ siderophore transport (from the transport system permease protein query) may be less essential to the microbial community of CP because of the high [Fe]. Conclusion: Further research is needed to confirm that these proteins are unique to photoautotrophs such as those living in iron-depositing hot spring.

  9. Watershed-Induced Limnological and Microbial Status in Two Oligotrophic Andean Lakes Exposed to the Same Climatic Scenario.

    Science.gov (United States)

    Echeverría-Vega, Alex; Chong, Guillermo; Serrano, Antonio E; Guajardo, Mariela; Encalada, Olga; Parro, Victor; Blanco, Yolanda; Rivas, Luis; Rose, Kevin C; Moreno-Paz, Mercedes; Luque, José A; Cabrol, Nathalie A; Demergasso, Cecilia S

    2018-01-01

    Laguna Negra and Lo Encañado are two oligotrophic Andean lakes forming part of the system fed by meltwater from distinct glacial tongues of the Echaurren glacier in central Chile, which is in a recession period. The recent increase in temperature and decline in precipitation have led to an increase of glacial meltwater and sediments entering these lakes. Although the lacustrine systems are also hydrogeologically connected, the limnology of the lakes is strongly controlled by the surface processes related to the respective sub-watersheds and hydrology. Watershed characteristics (area and length, slope, lithology, resistance to erosion, among others) affect the chemical and physical characteristics of both lakes (e.g., nutrient concentration and turbidity). We studied physical and chemical variables and performed 16S rRNA amplicon sequencing to determine the specific microbial signature of the lakes. The transparency, temperature, turbidity and concentrations of chlorophyll-a, dissolved organic matter, nutrients and the total number of cells, revealed the different status of both lakes at the time of sampling. The predominant bacterial groups in both lakes were Proteobacteria, Verrucomicrobia, and Bacteroidetes. Interestingly, the contribution of phototrophs was significantly higher in LN compared to LE (13 and 4% respectively) and the major fraction corresponded to Anoxygenic Phototrophs (AP) represented by Chloroflexi, Alpha, and Betaproteobacteria. Multivariate analyses showed that the nutrient levels and the light availability of both lakes, which finally depend on the hydrological characteristics of the respective watersheds, explain the differential community composition/function. The abundance of a diverse photoheterotrophic bacterioplankton community suggests that the ability to utilize solar energy along with organic and inorganic substrates is a key function in these oligotrophic mountain lakes.

  10. Fermentation couples Chloroflexi and sulfate-reducing bacteria to Cyanobacteria in hypersaline microbial mats

    Directory of Open Access Journals (Sweden)

    Jackson Z Lee

    2014-02-01

    Full Text Available Past studies of hydrogen cycling in hypersaline microbial mats have shown an active nighttime cycle, with production largely from Cyanobacteria and consumption from sulfate-reducing bacteria (SRB. However, the mechanisms and magnitude of hydrogen cycling have not been extensively studied. Two mats types near Guerrero Negro, Mexico -- permanently submerged Microcoleus microbial mats (GN-S, and intertidal Lyngbya microbial mats (GN-I -- were used in microcosm diel manipulation experiments with 3-(3,4-dichlorophenyl-1,1-dimethylurea (DCMU, molybdate, ammonium addition, and physical disruption to understand the processes responsible for hydrogen cycling between mat microbes. Across microcosms, H2 production occurred under dark anoxic conditions with simultaneous production of a suite of organic acids. H2 production was not significantly affected by inhibition of nitrogen fixation, but rather appears to result from constitutive fermentation of photosynthetic storage products by oxygenic phototrophs. Comparison to accumulated glycogen and to CO2 flux indicated that, in the GN-I mat, fermentation released almost all of the carbon fixed via photosynthesis during the preceding day, primarily as organic acids. Across mats, although oxygenic and anoxygenic phototrophs were detected, cyanobacterial [NiFe]-hydrogenase transcripts predominated. Molybdate inhibition experiments indicated that SRBs from a wide distribution of dsrA phylotypes were responsible for H2 consumption. Incubation with 13C-acetate and nanoSIMS (secondary ion mass-spectrometry indicated higher uptake in both Chloroflexi and SRBs relative to other filamentous bacteria. These manipulations and diel incubations confirm that Cyanobacteria were the main fermenters in Guerrero Negro mats and that the net flux of nighttime fermentation byproducts (not only hydrogen was largely regulated by the interplay between Cyanobacteria, SRBs, and Chloroflexi.

  11. Changes in the water quality and bacterial community composition of an alkaline and saline oxbow lake used for temporary reservoir of geothermal waters.

    Science.gov (United States)

    Borsodi, Andrea K; Szirányi, Barbara; Krett, Gergely; Márialigeti, Károly; Janurik, Endre; Pekár, Ferenc

    2016-09-01

    Geothermal waters exploited in the southeastern region of Hungary are alkali-hydrogen-carbonate type, and beside the high amount of dissolved salt, they contain a variety of aromatic, heteroaromatic, and polyaromatic hydrocarbons. The majority of these geothermal waters used for heating are directed into surface waters following a temporary storage in reservoir lakes. The aim of this study was to gain information about the temporal and spatial changes of the water quality as well as the bacterial community composition of an alkaline and saline oxbow lake operated as reservoir of used geothermal water. On the basis of the water physical and chemical measurements as well as the denaturing gradient gel electrophoresis (DGGE) patterns of the bacterial communities, temporal changes were more pronounced than spatial differences. During the storage periods, the inflow, reservoir water, and sediment samples were characterized with different bacterial community structures in both studied years. The 16S ribosomal RNA (rRNA) gene sequences of the bacterial strains and molecular clones confirmed the differences among the studied habitats. Thermophilic bacteria were most abundant in the geothermal inflow, whereas the water of the reservoir was dominated by cyanobacteria and various anoxygenic phototrophic prokaryotes. In addition, members of several facultative anaerobic denitrifying, obligate anaerobic sulfate-reducing and syntrophic bacterial species capable of decomposition of different organic compounds including phenols were revealed from the water and sediment of the reservoir. Most of these alkaliphilic and/or halophilic species may participate in the local nitrogen and sulfur cycles and contribute to the bloom of phototrophs manifesting in a characteristic pink-reddish discoloration of the water of the reservoir.

  12. Watershed-Induced Limnological and Microbial Status in Two Oligotrophic Andean Lakes Exposed to the Same Climatic Scenario

    Science.gov (United States)

    Echeverría-Vega, Alex; Chong, Guillermo; Serrano, Antonio E.; Guajardo, Mariela; Encalada, Olga; Parro, Victor; Blanco, Yolanda; Rivas, Luis; Rose, Kevin C.; Moreno-Paz, Mercedes; Luque, José A.; Cabrol, Nathalie A.; Demergasso, Cecilia S.

    2018-01-01

    Laguna Negra and Lo Encañado are two oligotrophic Andean lakes forming part of the system fed by meltwater from distinct glacial tongues of the Echaurren glacier in central Chile, which is in a recession period. The recent increase in temperature and decline in precipitation have led to an increase of glacial meltwater and sediments entering these lakes. Although the lacustrine systems are also hydrogeologically connected, the limnology of the lakes is strongly controlled by the surface processes related to the respective sub-watersheds and hydrology. Watershed characteristics (area and length, slope, lithology, resistance to erosion, among others) affect the chemical and physical characteristics of both lakes (e.g., nutrient concentration and turbidity). We studied physical and chemical variables and performed 16S rRNA amplicon sequencing to determine the specific microbial signature of the lakes. The transparency, temperature, turbidity and concentrations of chlorophyll-a, dissolved organic matter, nutrients and the total number of cells, revealed the different status of both lakes at the time of sampling. The predominant bacterial groups in both lakes were Proteobacteria, Verrucomicrobia, and Bacteroidetes. Interestingly, the contribution of phototrophs was significantly higher in LN compared to LE (13 and 4% respectively) and the major fraction corresponded to Anoxygenic Phototrophs (AP) represented by Chloroflexi, Alpha, and Betaproteobacteria. Multivariate analyses showed that the nutrient levels and the light availability of both lakes, which finally depend on the hydrological characteristics of the respective watersheds, explain the differential community composition/function. The abundance of a diverse photoheterotrophic bacterioplankton community suggests that the ability to utilize solar energy along with organic and inorganic substrates is a key function in these oligotrophic mountain lakes. PMID:29556224

  13. Efficacy and economics of different herbicides in aerobic rice system

    African Journals Online (AJOL)

    Jane

    2011-08-03

    Aug 3, 2011 ... options for effective and economic weed control in rice under aerobic system ... constraint to aerobic rice production and therefore, ... Herbicide has become an attractive alternative to manual ... MATERIALS AND METHODS.

  14. Mesophilic anaerobic stabilization of sewage sludge. Mesophile anaerobe Klaerschlammstabilisierung mit aerober Folgebehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Stoll, U.

    1988-01-01

    Sludges treated in two stages in experiments - 7 days of anaerobic treatment and 2 days of aerobic-thermophilic treatment - can be judged to be completely stabilized because of the stabilization parameters BOD/sub 5//COD ratio and respiratory activity. The degradation results obtained are comparable to or better than those of the 20-day digestion (reference process). For all aerobic processes under investigation a clear temperature increase in the aerobic reactor was measured because of the exothermal metabolic processes of the aerobic biocenosis. There was a temperature rise of 15/sup 0/C in the tests in the aerobic reactor even after longer digestion times of 15 and 20 days. The results of the epidemics and hygiene investigations show that a secondary aerobic-thermophilic stage after the mesophilic digestion with adequate marginal conditions - germ retention time of 23 hours in the aerobic reactor at process temperatures higher than 50/sup 0/C as well as charging in batch quantities - leads to a safe and complete decontamination. Under these process and operation conditions all salmonellae were killed and the number of the enterobacteriaceae in 1 g of sludge was always less than 1.000. (orig./EF).

  15. Differences in aerobic fitness between inpatients and outpatients with severe mental disorders

    Directory of Open Access Journals (Sweden)

    Helene Daae-Qvale Holmemo

    2014-08-01

    Full Text Available AbstractBackgroundPatients with severe mental disorders have increased mortality, and cardiovascular disease (CVD accounts for a large part. Physical inactivity and low aerobic fitness have been recognized as significant risk factors for CVD. In this study, we investigated the differences in aerobic fitness and physical activity between in- and outpatients with severe mental disorders. Method and subjectsFifty in- and outpatients from a regional psychiatric department were included. The patients filled in a questionnaire on physical activity and completed a clinical examination. An estimation of aerobic fitness was calculated for each patient, using gender, age, waist circumference, resting heart rate and physical activity level as variables.ResultsInpatients had lower estimated aerobic fitness than outpatients (VO₂peak 42 vs 50 mL•kg-1•min-1, p<0.001. Compared to population data matched for age and gender, inpatients had lower aerobic fitness, while outpatients were not different from the population average.ConclusionInpatients at a psychiatric department had lower estimated aerobic fitness than outpatients, and a lower aerobic fitness compared to the general population. Our findings suggest that inpatients with severe mental disorders should be considered a high risk group for CVD.

  16. Aerobic and anaerobic methanotrophic communities in urban landscape wetland.

    Science.gov (United States)

    Chen, Sili; Chen, Jianfei; Chang, Sha; Yi, Hao; Huang, Dawei; Xie, Shuguang; Guo, Qingwei

    2018-01-01

    Both aerobic methane-oxidizing bacteria (MOB) and nitrite-dependent anaerobic methane oxidation (n-damo) organisms can be important methane sinks in a wetland. However, the influences of the vegetation type on aerobic MOB and n-damo communities in wetland, especially in constructed wetland, remain poorly understood. The present study investigated the influences of the vegetation type on both aerobic MOB and n-damo organisms in a constructed urban landscape wetland. Sediments were collected from eight sites vegetated with different plant species. The abundance (1.19-3.27 × 10 7 pmoA gene copies per gram dry sediment), richness (Chao1 estimator = 16.3-81.5), diversity (Shannon index = 2.10-3.15), and structure of the sediment aerobic MOB community were found to vary considerably with sampling site. In contrast, n-damo community abundance (8.74 × 10 5 -4.80 × 10 6 NC10 16S rRNA gene copies per gram dry sediment) changed slightly with the sampling site. The richness (Chao1 estimator = 1-11), diversity (Shannon index = 0-0.78), and structure of the NC10 16S rRNA gene-based n-damo community illustrated slight site-related changes, while the spatial changes of the pmoA gene-based n-damo community richness (Chao1 estimator = 1-8), diversity (Shannon index = 0-0.99), and structure were considerable. The vegetation type could have a profound impact on the wetland aerobic MOB community and had a stronger influence on the pmoA-based n-damo community than on the NC10 16S-based one in urban wetland. Moreover, the aerobic MOB community had greater abundance and higher richness and diversity than the n-damo community. Methylocystis (type II MOB) predominated in urban wetland, while no known type I MOB species was detected. In addition, the ratio of total organic carbon to total nitrogen (C/N) might be a determinant of sediment n-damo community diversity and aerobic MOB richness.

  17. Aerobic fitness is associated with greater hippocampal cerebral blood flow in children

    Directory of Open Access Journals (Sweden)

    Laura Chaddock-Heyman

    2016-08-01

    Full Text Available The present study is the first to investigate whether cerebral blood flow in the hippocampus relates to aerobic fitness in children. In particular, we used arterial spin labeling (ASL perfusion MRI to provide a quantitative measure of blood flow in the hippocampus in 73 7- to 9-year-old preadolescent children. Indeed, aerobic fitness was found to relate to greater perfusion in the hippocampus, independent of age, sex, and hippocampal volume. Such results suggest improved microcirculation and cerebral vasculature in preadolescent children with higher levels of aerobic fitness. Further, aerobic fitness may influence how the brain regulates its metabolic demands via blood flow in a region of the brain important for learning and memory. To add specificity to the relationship of fitness to the hippocampus, we demonstrate no significant association between aerobic fitness and cerebral blood flow in the brainstem. Our results reinforce the importance of aerobic fitness during a critical period of child development.

  18. Grey water treatment in a series anaerobic--aerobic system for irrigation.

    Science.gov (United States)

    Abu Ghunmi, Lina; Zeeman, Grietje; Fayyad, Manar; van Lier, Jules B

    2010-01-01

    This study aims at treatment of grey water for irrigation, focusing on a treatment technology that is robust, simple to operate and with minimum energy consumption. The result is an optimized system consisting of an anaerobic unit operated in upflow mode, with a 1 day operational cycle, a constant effluent flow rate and varying liquid volume. Subsequent aerobic step is equipped with mechanical aeration and the system is insulated for sustaining winter conditions. The COD removal achieved by the anaerobic and aerobic units in summer and winter are 45%, 39% and 53%, 64%, respectively. Sludge in the anaerobic and aerobic reactor has a concentration of 168 and 8 mg VSL(-1), respectively. Stability of sludge in the anaerobic and aerobic reactors is 80% and 93%, respectively, based on COD. Aerobic effluent quality, except for pathogens, agrees with the proposed irrigation water quality guidelines for reclaimed water in Jordan.

  19. Aerobic fitness is associated with greater white matter integrity in children

    Directory of Open Access Journals (Sweden)

    Laura eChaddock-Heyman

    2014-08-01

    Full Text Available Aerobic fitness has been found to play a positive role in brain and cognitive health of children. Yet, many of the neural biomarkers related to aerobic fitness remain unknown. Here, using diffusion tensor imaging (DTI, we demonstrated that higher aerobic fitness was related to greater estimates of white matter microstructure in children. Higher fit 9- and 10-year-old children showed greater fractional anisotropy (FA in sections of the corpus callosum, corona radiata, and superior longitudinal fasciculus, compared to lower fit children. The FA effects were primarily characterized by aerobic fitness differences in radial diffusivity (RD, thereby raising the possibility that estimates of myelination may vary as a function of individual differences in fitness during childhood. White matter structure may be another potential neural mechanism of aerobic fitness that assists in efficient communication between gray matter regions as well as the integration of regions into networks.

  20. Aerob slamstabilisering. Driftserfaringer. Slamstabilitet

    OpenAIRE

    Haugan, B.-E.

    1981-01-01

    Det er foretatt en driftsundersøkelse av 8 renseanlegg for å kartlegge praktiske erfaringer med aerob slamstabilisering. Videre er det foretatt en driftsoppfølging av to renseanlegg for å koble driftsdata sammen med slamkvaliteten. Det er foretatt materialbalanse gjennom stabiliseringstrinnet NTNF's utvalg for drift av renseanlegg

  1. Acute effect on ambulatory blood pressure from aerobic exercise

    DEFF Research Database (Denmark)

    Lund Rasmussen, Charlotte; Nielsen, Line; Linander Henriksen, Marie

    2018-01-01

    session among female cleaners. METHODS: Twenty-two female cleaners were randomised to a cross-over study with a reference and an aerobic exercise session. Differences in 24-h, work hours, leisure time, and sleep ambulatory blood pressure (ABP) were evaluated using repeated measure 2 × 2 mixed...... of 1.5 mmHg (p = 0.03) were found after the aerobic exercise session. During leisure time, the systolic ABP was lowered by 1.7 mmHg (p = 0.04) and the diastolic ABP was unaltered. During sleep, the systolic and diastolic ABP was unaltered. CONCLUSION: A single aerobic exercise session lowered 24-h...

  2. Formation and functions of aerobic microbial granula; Entstehung und Funktionen aerober mikrobieller Granula

    Energy Technology Data Exchange (ETDEWEB)

    Etterer, T.; Wilderer, P.A. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl und Pruefamt fuer Wasserguete- und Abfallwirtschaft

    1999-07-01

    The present project investigates the phenomenon of the formation of aerobic microbial granula and their properties. To generate granula, sequencing batch reactors fed in batches were used. As shown by microbiological assays, fungi played an above-average role in granula formation and build-up. In first degradation experiments, furthermore, chemical oxygen demand (COD) could be reduced by over 90 %. The determination yielded comparable values to activated sludge, standing on average at 1.044g/ml. (orig.) [German] Im Rahmen des hier vorgestellten Projekts wurde das Phaenomen der Bildung aerober mikrobieller Granula sowie deren Eigenschaften untersucht. Zur Erzeugung von Granula wurden schubweise beschickte Reaktoren, sogenannte Sequencing-Batch-Reaktoren (SBR) verwendet. Wie mikrobiologische Untersuchungen zeigten spielen Pilze bei der Entstehung und beim Aufbau eine ueberdurchschnittliche Rolle. Des weiteren konnte in ersten Abbauversuchen der chemische Sauerstoff-Bedarf (CSB) um ueber 90% gesenkt werden. Die Dichtebestimmung ergab vergleichbare Werte zu Belebtschlamm und zwar im Durchschnitt 1,044 g/ml. (orig.)

  3. [Aerobic vaginitis--diagnostic problems and treatment].

    Science.gov (United States)

    Romanik, Małgorzata; Wojciechowska-Wieja, Anna; Martirosian, Gayane

    2007-06-01

    The diagnostic criteria and treatment of aerobic vaginitis--AV--have been summarized in this review. An expansion of mixed aerobic microflora, especially Group B Streptococcus--GBS, Escherichia coli--E. coli, Enterococcus spp., and the development of inflammation of the vaginal mucous membrane due to a decreasing amount of Lactobacillus spp., have been observed in women with AV. Disruptions of the vaginal ecosystem during AV cause an increase in pH to >6, a decrease in lactates concentration and an increase in proinflammatory cytokines concentration in vaginal discharge. An optimal treatment scheme for AV, which includes antibacterial agents and simultaneously normalizes the vaginal ecosystem, has not been established until today.

  4. Aerobic Fitness Thresholds Associated with Fifth Grade Academic Achievement

    Science.gov (United States)

    Wittberg, Richard; Cottrell, Lesley A.; Davis, Catherine L.; Northrup, Karen L.

    2010-01-01

    Background: Whereas effects of physical fitness and physical activity on cognitive function have been documented, little is known about how they are related. Purpose: This study assessed student aerobic fitness measured by FITNESSGRAM Mile times and/or Pacer circuits and whether the nature of the association between aerobic fitness and…

  5. Production and Consumption of Hydrogen in Hot Spring Microbial Mats Dominated by a Filamentous Anoxygenic Photosynthetic Bacterium

    Science.gov (United States)

    Otaki, Hiroyo; Everroad, R. Craig; Matsuura, Katsumi; Haruta, Shin

    2012-01-01

    Microbial mats containing the filamentous anoxygenic photosynthetic bacterium Chloroflexus aggregans develop at Nakabusa hot spring in Japan. Under anaerobic conditions in these mats, interspecies interaction between sulfate-reducing bacteria as sulfide producers and C. aggregans as a sulfide consumer has been proposed to constitute a sulfur cycle; however, the electron donor utilized for microbial sulfide production at Nakabusa remains to be identified. In order to determine this electron donor and its source, ex situ experimental incubation of mats was explored. In the presence of molybdate, which inhibits biological sulfate reduction, hydrogen gas was released from mat samples, indicating that this hydrogen is normally consumed as an electron donor by sulfate-reducing bacteria. Hydrogen production decreased under illumination, indicating that C. aggregans also functions as a hydrogen consumer. Small amounts of hydrogen may have also been consumed for sulfur reduction. Clone library analysis of 16S rRNA genes amplified from the mats indicated the existence of several species of hydrogen-producing fermentative bacteria. Among them, the most dominant fermenter, Fervidobacterium sp., was successfully isolated. This isolate produced hydrogen through the fermentation of organic carbon. Dispersion of microbial cells in the mats resulted in hydrogen production without the addition of molybdate, suggesting that simultaneous production and consumption of hydrogen in the mats requires dense packing of cells. We propose a cyclic electron flow within the microbial mats, i.e., electron flow occurs through three elements: S (elemental sulfur, sulfide, sulfate), C (carbon dioxide, organic carbon) and H (di-hydrogen, protons). PMID:22446313

  6. Physiology and genetics of sulfur-oxidizing bacteria.

    Science.gov (United States)

    Friedrich, C G

    1998-01-01

    Reduced inorganic sulfur compounds are oxidized by members of the domains Archaea and Bacteria. These compounds are used as electron donors for anaerobic phototrophic and aerobic chemotrophic growth, and are mostly oxidized to sulfate. Different enzymes mediate the conversion of various reduced sulfur compounds. Their physiological function in sulfur oxidation is considered (i) mostly from the biochemical characterization of the enzymatic reaction, (ii) rarely from the regulation of their formation, and (iii) only in a few cases from the mutational gene inactivation and characterization of the resulting mutant phenotype. In this review the sulfur-metabolizing reactions of selected phototrophic and of chemotrophic prokaryotes are discussed. These comprise an archaeon, a cyanobacterium, green sulfur bacteria, and selected phototrophic and chemotrophic proteobacteria. The genetic systems are summarized which are presently available for these organisms, and which can be used to study the molecular basis of their dissimilatory sulfur metabolism. Two groups of thiobacteria can be distinguished: those able to grow with tetrathionate and other reduced sulfur compounds, and those unable to do so. This distinction can be made irrespective of their phototrophic or chemotrophic metabolism, neutrophilic or acidophilic nature, and may indicate a mechanism different from that of thiosulfate oxidation. However, the core enzyme for tetrathionate oxidation has not been identified so far. Several phototrophic bacteria utilize hydrogen sulfide, which is considered to be oxidized by flavocytochrome c owing to its in vitro activity. However, the function of flavocytochrome c in vivo may be different, because it is missing in other hydrogen sulfide-oxidizing bacteria, but is present in most thiosulfate-oxidizing bacteria. A possible function of flavocytochrome c is discussed based on biophysical studies, and the identification of a flavocytochrome in the operon encoding enzymes involved

  7. Interaction between age and aerobic fitness in determining heart rate dynamics

    International Nuclear Information System (INIS)

    McNarry, M A; Lewis, M J

    2012-01-01

    Heart rate variability (HRV) and phase-rectified signal averaging (PRSA) estimates of heart rate dynamics are diminished in older people compared with younger people. However, it is not fully elucidated whether these differences are related to age per se or to the concomitant influence of aerobic fitness. Aerobic fitness (peak oxygen uptake, gas exchange threshold, oxygen uptake kinetics, exercise economy) was assessed in 70 healthy adults (41 male) aged 18–57 years. Participants also underwent a 24 h, ambulatory ECG for the derivation of HRV and PRSA variables. HRV was most sensitive to age and aerobic fitness when measured during the morning period (6 am–12 pm). HRV and PRSA were both diminished with age and were higher in aerobically superior participants. The decline in HRV with age was predominantly attributable to age itself (33%), with aerobic fitness representing an additional modulating factor. The present study also provides tentative evidence that assessment of the influence of aerobic fitness should not rely on .VO 2peak alone. These findings demonstrate that age per se is an important factor in determining HRV. However, given the clinical importance of diminished HRV and the immutable nature of aging, the potential significance of physical activity/training to enhance cardiac regulatory function should not be underestimated. (paper)

  8. COD fractions of leachate from aerobic and anaerobic pilot scale landfill reactors

    International Nuclear Information System (INIS)

    Bilgili, M. Sinan; Demir, Ahmet; Akkaya, Ebru; Ozkaya, Bestamin

    2008-01-01

    One of the most important problems with designing and maintaining a landfill is managing leachate that generated when water passes through the waste. In this study, leachate samples taken from aerobic and anaerobic landfill reactors operated with and without leachate recirculation are investigated in terms of biodegradable and non-biodegradable fractions of COD. The operation time is 600 days for anaerobic reactors and 250 days for aerobic reactors. Results of this study show that while the values of soluble inert COD to total COD in the leachate of aerobic landfill with leachate recirculation and aerobic dry reactors are determined around 40%, this rate was found around 30% in the leachate of anaerobic landfill with leachate recirculation and traditional landfill reactors. The reason for this difference is that the aerobic reactors generated much more microbial products. Because of this condition, it can be concluded that total inert COD/total COD ratios of the aerobic reactors were 60%, whereas those of anaerobic reactors were 50%. This study is important for modeling, design, and operation of landfill leachate treatment systems and determination of discharge limits

  9. Role of seagrass photosynthesis in root aerobic processes.

    Science.gov (United States)

    Smith, R D; Dennison, W C; Alberte, R S

    1984-04-01

    The role of shoot photosynthesis as a means of supporting aerobic respiration in the roots of the seagrass Zostera marina was examined. O(2) was transported rapidly (10-15 minutes) from the shoots to the root-rhizome tissues upon shoot illumination. The highest rates of transport were in shoots possessing the greatest biomass and leaf area. The rates of O(2) transport do not support a simple gas phase diffusion mechanism. O(2) transport to the root-rhizome system supported aerobic root respiration and in many cases exceeded respiratory requirements leading to O(2) release from the subterranean tissue. Release of O(2) can support aerobic processes in reducing sediments typical of Z. marina habitats. Since the root-rhizome respiration is supported primarily under shoot photosynthetic conditions, then the daily period of photosynthesis determines the diurnal period of root aerobiosis.

  10. Processing biodegradable waste by applying aerobic digester EWA

    OpenAIRE

    Đokić, Dragoslav; Lugić, Zoran; Terzić, Dragan; Jevtić, Goran; Milenković, Jasmina; Húrka, Miroslav; Stanisavljević, Rade

    2014-01-01

    The paper presents research results obtained in the process of processing biodegradable wastes, resulting from agricultural production as well as municipal waste. Aerobic fermenter EWA (stationed within the Institute for Forage Crops Globoder- Kruševac) was using for this purpose, during the one month testing. Biodegradable material with different ratios of components was used for filling aerobic digester. EWA fermenter is certified device that is used to stabilize and hygienic disposal of bi...

  11. Reductive Dechlorination of Trichloroethylene and Tetrachloroethylene under Aerobic Conditions in a Sediment Column

    OpenAIRE

    1994-01-01

    Biodegradation of trichloroethylene and tetrachloroethylene under aerobic conditions was studied in a sediment column. Cumulative mass balances indicated 87 and 90% removal for trichloroethylene and tetrachloroethylene, respectively. These studies suggest the potential for simultaneous aerobic and anaerobic biotransformation processes under bulk aerobic conditions.

  12. Effect of resistance and aerobic exercises on bone mineral density ...

    African Journals Online (AJOL)

    Conclusion: Based on obtained data, it can be concluded that, resistance and aerobic exercise training program is effective in increasing BMD, muscle strength and functional ability in children with hemophilia. Keywords: Hemophilia; Resistance; Aerobic exercise; Bone mineral density; Strength; Functional ability ...

  13. Aerobic Activity Preferences among Older Canadians: A Time Use Perspective.

    Science.gov (United States)

    Spinney, Jamie E L

    2013-12-01

    Numerous health benefits are associated with a physically active population. This study sought to discover the aerobic activity preferences among older Canadians. Four cycles of nationally representative time use data were fused with energy expenditure information to determine both participation rates and time spent in the 10 most frequently reported aerobic activities. Aerobic activity preferences are dominated by domestic chores (15% to 30% participation for about two hours per day), recreational walking (15% to 30% participation for about one hour per day), and active transportation (generally less than 5% participation for less than 30 minutes per day). Although there have been several changes in older Canadians’ revealed preferences for aerobic activities over the past three decades, the prevalence of domestic chores points towards the importance of policies that support older Canadians remaining in their homes, whereas the popularity of walking suggests that “walkability” needs to be considered in neighbourhood design.

  14. Aerobic training for improved memory in patients with stress-related exhaustion

    DEFF Research Database (Denmark)

    Eskilsson, Therese; Slunga Järvholm, Lisbeth; Malmberg Gavelin, Hanna

    2017-01-01

    BACKGROUND: Patients with stress-related exhaustion suffer from cognitive impairments, which often remain after psychological treatment or work place interventions. It is important to find effective treatments that can address this problem. Therefore, the aim of this study was to investigate...... the effects on cognitive performance and psychological variables of a 12-week aerobic training program performed at a moderate-vigorous intensity for patients with exhaustion disorder who participated in a multimodal rehabilitation program. METHODS: In this open-label, parallel, randomized and controlled...... was cognitive function, and secondary outcome measures were psychological health variables and aerobic capacity. RESULTS: In total, 51% patients in the aerobic training group and 78% patients in the control group completed the intervention period. The aerobic training group significantly improved in maximal...

  15. Effects of 16 weeks of aerobic, resistance and combination exercise ...

    African Journals Online (AJOL)

    Effects of 16 weeks of aerobic, resistance and combination exercise programmes on smoking. ... African Journal for Physical Activity and Health Sciences ... Abstract. Previous research on the cessation of smoking and the prevention of smoking recidivism using exercise training has mainly focused on aerobic training (AER).

  16. Aerobic training in persons who have recovered from juvenile dermatomyositis

    DEFF Research Database (Denmark)

    Riisager, M; Mathiesen, P R; Vissing, J

    2013-01-01

    A recent study has shown that 36 persons who had recovered from juvenile dermatomyositis (JDM) have on average an 18% decrease in maximal oxygen uptake. The objective of this study was to investigate the effect of a 12-week aerobic training program in this group, and assess whether aerobic training...... can normalize aerobic capacity to the expected level for age and gender. The patients participating in the study, one male and nine females (16-42years of age), were in remission from JDM, defined as no clinical or biochemical evidence of disease activity and no medical treatment for 1year...

  17. Aerobic exercise combined with huwentoxin-I mitigates chronic cerebral ischemia injury

    Directory of Open Access Journals (Sweden)

    Hai-feng Mao

    2017-01-01

    Full Text Available Ca2+ channel blockers have been shown to protect neurons from ischemia, and aerobic exercise has significant protective effects on a variety of chronic diseases. The present study injected huwentoxin-I (HWTX-I, a spider peptide toxin that blocks Ca2+ channels, into the caudal vein of a chronic cerebral ischemia mouse model, once every 2 days, for a total of 15 injections. During this time, a subgroup of mice was subjected to treadmill exercise for 5 weeks. Results showed amelioration of cortical injury and improved neurological function in mice with chronic cerebral ischemia in the HWTX-I + aerobic exercise group. The combined effects of HWTX-I and exercise were superior to HWTX-I or aerobic exercise alone. HWTX-I effectively activated the Notch signal transduction pathway in brain tissue. Aerobic exercise up-regulated synaptophysin mRNA expression. These results demonstrated that aerobic exercise, in combination with HWTX-I, effectively relieved neuronal injury induced by chronic cerebral ischemia via the Notch signaling pathway and promoting synaptic regeneration.

  18. Effects of concurrent and aerobic exercises on postexercise hypotension in elderly hypertensive men.

    Science.gov (United States)

    Ferrari, Rodrigo; Umpierre, Daniel; Vogel, Guilherme; Vieira, Paulo J C; Santos, Lucas P; de Mello, Renato Bandeira; Tanaka, Hirofumi; Fuchs, Sandra C

    2017-11-01

    Despite the fact that simultaneous performance of resistance and aerobic exercises (i.e., concurrent exercise) has become a standard exercise prescription for the elderly, no information is available on its effects on post-exercise hypotension (PEH) in elderly men with hypertension. To compare the effects of different types of exercise on PEH in elderly men with hypertension. Twenty elderly men with essential hypertension participated in three crossover interventions, in random order, and on separate days: a non-exercise control session at seated rest, aerobic exercise performed for 45min, and 45min of concurrent resistance and aerobic exercise consisted of 4 sets of 8 repetitions at 70% 1RM of resistance exercise followed by aerobic exercise on treadmill. After each session, blood pressure (BP) was measured continuously for 1h in the laboratory and for 24h under ambulatory conditions. During the first hour in laboratory, diastolic BP was lower after aerobic (-5mmHg) and concurrent exercise (-6mmHg) in comparison with Control. Day-time diastolic BP was significantly lower after aerobic exercise (-7mmHg) when compared to the control. No significant differences were found among the three experimental sessions for night-time and 24-hour diastolic BP, as well as day-time, night-time and 24-hour systolic BP. Concurrent exercise produced acute PEH similar to aerobic exercise but such effect did not last as long as aerobic exercise in elderly patients with essential hypertension. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Kinetics of aerobic cometabolic biodegradation of chlorinated and brominated aliphatic hydrocarbons: A review.

    Science.gov (United States)

    Jesus, João; Frascari, Dario; Pozdniakova, Tatiana; Danko, Anthony S

    2016-05-15

    This review analyses kinetic studies of aerobic cometabolism (AC) of halogenated aliphatic hydrocarbons (HAHs) from 2001-2015 in order to (i) compare the different kinetic models proposed, (ii) analyse the estimated model parameters with a focus on novel HAHs and the identification of general trends, and (iii) identify further research needs. The results of this analysis show that aerobic cometabolism can degrade a wide range of HAHs, including HAHs that were not previously tested such as chlorinated propanes, highly chlorinated ethanes and brominated methanes and ethanes. The degree of chlorine mineralization was very high for the chlorinated HAHs. Bromine mineralization was not determined for studies with brominated aliphatics. The examined research period led to the identification of novel growth substrates of potentially high interest. Decreasing performance of aerobic cometabolism were found with increasing chlorination, indicating the high potential of aerobic cometabolism in the presence of medium- and low-halogenated HAHs. Further research is needed for the AC of brominated aliphatic hydrocarbons, the potential for biofilm aerobic cometabolism processes, HAH-HAH mutual inhibition and the identification of the enzymes responsible for each aerobic cometabolism process. Lastly, some indications for a possible standardization of future kinetic studies of HAH aerobic cometabolism are provided. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Aerobic capacity mediates susceptibility for the transition from steatosis to steatohepatitis.

    Science.gov (United States)

    Morris, E Matthew; McCoin, Colin S; Allen, Julie A; Gastecki, Michelle L; Koch, Lauren G; Britton, Steven L; Fletcher, Justin A; Fu, Xiarong; Ding, Wen-Xing; Burgess, Shawn C; Rector, R Scott; Thyfault, John P

    2017-07-15

    Low intrinsic aerobic capacity is associated with increased all-cause and liver-related mortality in humans. Low intrinsic aerobic capacity in the low capacity runner (LCR) rat increases susceptibility to acute and chronic high-fat/high-sucrose diet-induced steatosis, without observed increases in liver inflammation. Addition of excess cholesterol to a high-fat/high-sucrose diet produced greater steatosis in LCR and high capacity runner (HCR) rats. However, the LCR rat demonstrated greater susceptibility to increased liver inflammatory and apoptotic markers compared to the HCR rat. The progressive non-alcoholic fatty liver disease observed in the LCR rats following western diet feeding was associated with further declines in liver fatty acid oxidation and mitochondrial respiratory capacity compared to HCR rats. Low aerobic capacity increases risk for non-alcoholic fatty liver disease and liver-related disease mortality, but mechanisms mediating these effects remain unknown. We recently reported that rats bred for low aerobic capacity (low capacity runner; LCR) displayed susceptibility to high fat diet-induced steatosis in association with reduced hepatic mitochondrial fatty acid oxidation (FAO) and respiratory capacity compared to high aerobic capacity (high capacity runner; HCR) rats. Here we tested the impact of aerobic capacity on susceptibility for progressive liver disease following a 16-week 'western diet' (WD) high in fat (45% kcal), cholesterol (1% w/w) and sucrose (15% kcal). Unlike previously with a diet high in fat and sucrose alone, the inclusion of cholesterol in the WD induced hepatomegaly and steatosis in both HCR and LCR rats, while producing greater cholesterol ester accumulation in LCR compared to HCR rats. Importantly, WD-fed low-fitness LCR rats displayed greater inflammatory cell infiltration, serum alanine transaminase, expression of hepatic inflammatory markers (F4/80, MCP-1, TLR4, TLR2 and IL-1β) and effector caspase (caspase 3 and 7

  1. Constant growth rate can be supported by decreasing energy flux and increasing aerobic glycolysis

    NARCIS (Netherlands)

    Slavov, Nikolai; Budnik, Bogdan A; Schwab, David; Airoldi, Edoardo M; van Oudenaarden, Alexander

    2014-01-01

    Fermenting glucose in the presence of enough oxygen to support respiration, known as aerobic glycolysis, is believed to maximize growth rate. We observed increasing aerobic glycolysis during exponential growth, suggesting additional physiological roles for aerobic glycolysis. We investigated such

  2. Aerobic Exercise During Encoding Impairs Hippocampus-Dependent Memory.

    Science.gov (United States)

    Soga, Keishi; Kamijo, Keita; Masaki, Hiroaki

    2017-08-01

    We investigated how aerobic exercise during encoding affects hippocampus-dependent memory through a source memory task that assessed hippocampus-independent familiarity and hippocampus-dependent recollection processes. Using a within-participants design, young adult participants performed a memory-encoding task while performing a cycling exercise or being seated. The subsequent retrieval phase was conducted while sitting on a chair. We assessed behavioral and event-related brain potential measures of familiarity and recollection processes during the retrieval phase. Results indicated that source accuracy was lower for encoding with exercise than for encoding in the resting condition. Event-related brain potential measures indicated that the parietal old/new effect, which has been linked to recollection processing, was observed in the exercise condition, whereas it was absent in the rest condition, which is indicative of exercise-induced hippocampal activation. These findings suggest that aerobic exercise during encoding impairs hippocampus-dependent memory, which may be attributed to inefficient source encoding during aerobic exercise.

  3. Low-intensity training dissociates metabolic from aerobic fitness

    DEFF Research Database (Denmark)

    Helge, J W; Damsgaard, R; Overgaard, K

    2008-01-01

    This study investigated the effect of prolonged whole-body low-intensity exercise on blood lipids, skeletal muscle adaptations and aerobic fitness. Seven male subjects completed a 32-day crossing of the Greenland icecap on cross-country skies and before and after this arm or leg cranking was perf......This study investigated the effect of prolonged whole-body low-intensity exercise on blood lipids, skeletal muscle adaptations and aerobic fitness. Seven male subjects completed a 32-day crossing of the Greenland icecap on cross-country skies and before and after this arm or leg cranking...... sensitive lipase activity was similar in arm and leg muscle prior to the expedition and was not significantly affected by the crossing. In conclusion, an improved blood lipid profile and thus metabolic fitness was present after prolonged low-intensity training and this occurred in spite of a decreased...... aerobic fitness and an unchanged arm and leg muscle hormone-sensitive lipase activity....

  4. [EPIDEMIOLOGICAL, CLINICAL AND MICROBIOLOGICAL FINDINGS IN WOMEN WITH AEROBIC VAGINITIS].

    Science.gov (United States)

    Dermendjiev, T; Pehlivanov, B; Hadjieva, K; Stanev, S

    2015-01-01

    Aerobic vaginitis (AV) is an alterarion of the normal lactobacillic flora accompanied by signs of inflammation, presence of mainly aerobic microorganisms from intestinal commensals or other aerobic pathogens. Clinical symptoms may vary by type and intensity and are marked by a high tendency for recurrence and chronification. Inflammation and ulcerations in AV could increase the risk of contracting HIV or other sexually transmitted infections. The aim is to study some epidemiological, clinical and microbiological features of the aerobic vaginitis in patients of the specialized Obstetric and Gynecological Clinic in Plovdiv, Bulgaria. In a retrospective research 4687 vaginal smears have been gathered in Microbiological laboratory at "St. George" Hospital - Plovdiv. We used clinical, microbiological and statistical methods. Information processing is performed by variation, alternative, correlation and graphical analysis using specialized package SPSS v13.0. The overall prevalence rate of AV in the studied population is 11.77%. The levels of prevalence of AV in pregnant and non-pregnant women are respectively 13.08% and 4.34%. The highest frequency of AV is in the age group 21-30 years (32.3%). The results show a marked association between Escherichia coli and the cases of AV (p vaginal symptoms in patients of specialized ambulatory outpatient. One in ten women with vaginal complaints suffers from AV Streptococcus agalactiae and Escherichia coli are most often isolated aerobic microorganisms.

  5. Anthropometry, somatotypes, and aerobic power in ballet, contemporary dance, and dancesport.

    Science.gov (United States)

    Liiv, Helena; Wyon, Matthew A; Jürimäe, Toivo; Saar, Meeli; Mäestu, Jarek; Jürimäe, Jaak

    2013-12-01

    This study compared anthropometric variables, somatotypes, and aerobic capacity between three groups of dancers: classical ballet dancers (M 33, F 56), contemporary dancers (M 28, F 109), and dancesport dancers (M 30, F 30). The assumption was that different functional requirements should produce differences in the anthropometric and aerobic capacity variables among the three groups. Anthropometric data for body mass index (BMI) and somatotypes were measured. Body fat percentage was measured by dual-energy x-ray absorptiometry. Maximal oxygen consumption and aerobic power were measured during an incremental treadmill test until exhaustion. Dancesport athletes were taller compared with same gender contemporary dancers (pballet dancers had a lower body mass and BMI compared with their contemporary dance and dancesport equivalents (pballet counterparts, while dancesport dancers are taller and heavier, less muscular, with slightly greater adioposity compared to the classical ballet dancers. Ballet dancers had the lowest body fat percentage, weight, and BMI values. Dancesport dancers had greater aerobic capacity than the ballet dancers. Based on this study, we conclude that dancers in these three styles differ in some aspects of anthropometric variables, somatotypes, and aerobic capacity, but we cannot say is it because of the training or selection or both.

  6. The effect of acute aerobic and resistance exercise on working memory.

    Science.gov (United States)

    Pontifex, Matthew B; Hillman, Charles H; Fernhall, Bo; Thompson, Kelli M; Valentini, Teresa A

    2009-04-01

    The goal of this investigation was to assess the influence of acute bouts of aerobic versus resistance exercise on the executive control of working memory. Twenty-one young adult participants completed a cardiorespiratory fitness test and maximal strength tests. On subsequent days, task performance measures of reaction time (RT) and accuracy were collected while participants completed a modified Sternberg working memory task before the start of, immediately after, and 30 min after an intervention consisting of 30 min of either resistance or aerobic exercise and a seated rest control. Findings indicated shorter RT immediately and 30 min after acute aerobic exercise relative to the preexercise baseline with no such effects observed after resistance exercise or seated rest. Further, in the aerobic condition, a larger reduction in RT from the baseline occurred during task conditions requiring increased working memory capacity. Again, no effect was observed in the resistance exercise or the seated rest conditions. These data extend the current knowledge base by indicating that acute exercise-induced changes in cognition are disproportionately related to executive control and may be specific to the aerobic exercise domain.

  7. Enhancement of aerobic granulation by zero-valent iron in sequencing batch airlift reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Qiang, E-mail: kongqiang0531@hotmail.com [College of Life Science, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong (China); Ngo, Huu Hao [School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW 2007 (Australia); Shu, Li [School of Engineering, Faculty of Science, Engineering and Built Environment, Deakin University, Geelong, Victoria 3216 (Australia); Fu, Rong-shu; Jiang, Chun-hui [College of Life Science, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong (China); Miao, Ming-sheng, E-mail: mingshengmiao@163.com [College of Life Science, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong (China)

    2014-08-30

    Highlights: • Zero-valent iron (ZVI) was used firstly to enhance the aerobic granulation. • ZVI significantly decreased the start-up time of the aerobic granulation. • ZVI had the function of enhancing organic material diversity identified by 3-D EEM. • ZVI could enhance the diversity of microbial community. - Abstract: This study elucidates the enhancement of aerobic granulation by zero-valent iron (ZVI). A reactor augmented with ZVI had a start-up time of aerobic granulation (43 days) that was notably less than that for a reactor without augmentation (64 days). The former reactor also had better removal efficiencies for chemical oxygen demand and ammonium. Moreover, the mature granules augmented with ZVI had better physical characteristics and produced more extracellular polymeric substances (especially of protein). Three-dimensional-excitation emission matrix fluorescence showed that ZVI enhanced organic material diversity. Additionally, ZVI enhanced the diversity of the microbial community. Fe{sup 2+} dissolution from ZVI helped reduce the start-up time of aerobic granulation and increased the extracellular polymeric substance content. Conclusively, the use of ZVI effectively enhanced aerobic granulation.

  8. Enhancement of aerobic granulation by zero-valent iron in sequencing batch airlift reactor

    International Nuclear Information System (INIS)

    Kong, Qiang; Ngo, Huu Hao; Shu, Li; Fu, Rong-shu; Jiang, Chun-hui; Miao, Ming-sheng

    2014-01-01

    Highlights: • Zero-valent iron (ZVI) was used firstly to enhance the aerobic granulation. • ZVI significantly decreased the start-up time of the aerobic granulation. • ZVI had the function of enhancing organic material diversity identified by 3-D EEM. • ZVI could enhance the diversity of microbial community. - Abstract: This study elucidates the enhancement of aerobic granulation by zero-valent iron (ZVI). A reactor augmented with ZVI had a start-up time of aerobic granulation (43 days) that was notably less than that for a reactor without augmentation (64 days). The former reactor also had better removal efficiencies for chemical oxygen demand and ammonium. Moreover, the mature granules augmented with ZVI had better physical characteristics and produced more extracellular polymeric substances (especially of protein). Three-dimensional-excitation emission matrix fluorescence showed that ZVI enhanced organic material diversity. Additionally, ZVI enhanced the diversity of the microbial community. Fe 2+ dissolution from ZVI helped reduce the start-up time of aerobic granulation and increased the extracellular polymeric substance content. Conclusively, the use of ZVI effectively enhanced aerobic granulation

  9. Effect of an aerobic-based physical activity programme on physical ...

    African Journals Online (AJOL)

    The purpose of this study was to determine whether a 10 week aerobic-based exercise programme performed twice a week, with a 30 minutes duration and an intensity level of 55 – 70% heart rate max would improve aerobic endurance, muscular strength, muscular endurance, flexibility and body composition of 10 – 15 ...

  10. Aerobic endurance in HIV-positive young adults and HIV-negative ...

    African Journals Online (AJOL)

    Background: Aerobic endurance is an important aspect of physical fitness that enables individuals living with HIV to endure in the work place as well as in agricultural operations in order to earn a living and improve their quality of life. However, despite high HIV prevalence rates, the aerobic endurance status of young ...

  11. The threat of aerobic vaginitis to pregnancy and neonatal morbidity ...

    African Journals Online (AJOL)

    Aerobic vaginitis (AV) is an endogenous opportunistic infection brought about by the disruption of the normal vaginal microbiota. Its early diagnosis and treatment during pregnancy may reduce the risk of negative pregnancy outcomes. The aim of this review was to report on the aerobic bacteria most prevalent in AV and to ...

  12. Aerobic exercise increases hippocampal volume and improves memory in multiple sclerosis: preliminary findings.

    Science.gov (United States)

    Leavitt, V M; Cirnigliaro, C; Cohen, A; Farag, A; Brooks, M; Wecht, J M; Wylie, G R; Chiaravalloti, N D; DeLuca, J; Sumowski, J F

    2014-01-01

    Multiple sclerosis leads to prominent hippocampal atrophy, which is linked to memory deficits. Indeed, 50% of multiple sclerosis patients suffer memory impairment, with negative consequences for quality of life. There are currently no effective memory treatments for multiple sclerosis either pharmacological or behavioral. Aerobic exercise improves memory and promotes hippocampal neurogenesis in nonhuman animals. Here, we investigate the benefits of aerobic exercise in memory-impaired multiple sclerosis patients. Pilot data were collected from two ambulatory, memory-impaired multiple sclerosis participants randomized to non-aerobic (stretching) and aerobic (stationary cycling) conditions. The following baseline/follow-up measurements were taken: high-resolution MRI (neuroanatomical volumes), fMRI (functional connectivity), and memory assessment. Intervention was 30-minute sessions 3 times per week for 3 months. Aerobic exercise resulted in 16.5% increase in hippocampal volume and 53.7% increase in memory, as well as increased hippocampal resting-state functional connectivity. Improvements were specific, with no comparable changes in overall cerebral gray matter (+2.4%), non-hippocampal deep gray matter structures (thalamus, caudate: -4.0%), or in non-memory cognitive functioning (executive functions, processing speed, working memory: changes ranged from -11% to +4%). Non-aerobic exercise resulted in relatively no change in hippocampal volume (2.8%) or memory (0.0%), and no changes in hippocampal functional connectivity. This is the first evidence for aerobic exercise to increase hippocampal volume and connectivity and improve memory in multiple sclerosis. Aerobic exercise represents a cost-effective, widely available, natural, and self-administered treatment with no adverse side effects that may be the first effective memory treatment for multiple sclerosis patients.

  13. Effects of Aerobic Training on Primary Dysmenorrhea Symptomatology in College Females.

    Science.gov (United States)

    Israel, Richard G.; And Others

    1985-01-01

    This study investigated the effects of a 12-week aerobic training program on menstrual distress symptoms in college females with clinically diagnosed primary dysmenorrhea. The findings suggest that aerobic training can significantly reduce the symptoms associated with primary dysmenorrhea. (Author/MT)

  14. Aerobic Exercise Increases Peripheral and Hepatic Insulin Sensitivity in Sedentary Adolescents

    NARCIS (Netherlands)

    van der Heijden, Gert-Jan; Toffolo, Gianna; Manesso, Erica; Sauer, Pieter J. J.; Sunehag, Agneta L.

    2009-01-01

    Context: Data are limited on the effects of controlled aerobic exercise programs (without weight loss) on insulin sensitivity and glucose metabolism in children and adolescents. Objective: To determine whether a controlled aerobic exercise program (without weight loss) improves peripheral and

  15. Decomposition of Rice Straw and Corn Straw Under Aerobic and Anaerobic Conditions

    Directory of Open Access Journals (Sweden)

    WANG Jing

    2017-01-01

    Full Text Available Decomposition dynamics of rice straw and corn straw at aerobic and anaerobic condition were investigated under the simulated condition in the lab. Results showed that two stages, i.e. the rapid decomposition stage from 0 to 3 months, and the slow one between 3 and 12 months, of decomposition dynamics of rice straw and corn straw were found under anaerobic and aerobic incubation condition, and more than 55%of rice straw and corn mass was lost at the initial 3 months incubation period. The half times(t1/2of rice straw and corn straw mass lost under aerobic condition were 59.2 d and 52.9 d, which were short than those(72.6 d and 79.9 dunder the anaerobic condition, respectively. Carbon release constants from rice straw and corn straw under aerobic condition were 0.61 and 0.60 per month, which were higher than those (0.55 and 0.57 per monthunder anaerobic condition. The nitrogen release from crop straw followed the same rule as the carbon release from straw. The constants of nitrogen released from rice straw and corn straw under aerobic condition were 0.25 and 2.36 per month, which were higher than those(0.16 and 2.32 per monthunder anaerobic condition. The losses of cellulose, hemicelluloses and lignin from rice straw and corn straw under aerobic condition were also higher than those under anaerobic condition. In summary, the aerobic environment increases de composition and release of organic and inorganic substances from crop straw.

  16. Enhanced aerobic degradation of 4-chlorophenol with iron-nickel nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Wenjuan; Mu, Yi; Wang, Bingning; Ai, Zhihui, E-mail: jennifer.ai@mail.ccnu.edu.cn; Zhang, Lizhi

    2017-01-30

    Highlights: • Bimetallic iron-nickel nanoparticles possessed an enhanced performance on aerobic degradation of 4-CP. • Hydroxyl radicals were the major active species contributed to aerobic 4-CP degradation with nZVI. • Superoxide radicals predominated the 4-CP degradation in the nZVIN/Air process. • The 4-CP degradation pathways were dependent on the generated superoxide radicals in the nZVIN/Air process. - Abstract: In this study, we demonstrate that the bimetallic iron-nickel nanoparticles (nZVIN) possessed an enhanced performance in comparison with nanoscale zero-valent iron (nZVI) on aerobic degradation of 4-chlorophenol (4-CP). The 4-CP degradation rate constant in the aerobic nZVIN process (nZVIN/Air) was 5 times that in the classic nZVI counterpart system (nZVI/Air). Both reactive oxygen species measurement and inhibition experimental results suggested that hydroxyl radicals were the major active species contributed to aerobic 4-CP degradation with nZVI, on contrast, superoxide radicals predominated the 4-CP degradation in the nZVIN/Air process. High performance liquid chromatography and gas chromatography-mass spectrometer analysis indicated the intermediates of the nZVI/Air system were p-benzoquinone and hydroquinone, which were resulted from the bond cleavage between the chlorine and carbon atom in the benzene ring by hydroxyl radicals. However, the primary intermediates of 4-CP found in the nZVIN/Air system were phenol via the direct dechlorination by superoxide radicals, accompanying with the formation of chloride ions. On the base of experimental results, a superoxide radicals mediated enhancing mechanism was proposed for the aerobic degradation of 4-CP in the nZVIN/Air system. This study provides new insight into the role of bimetallic nickel on enhancing removal of organic pollutants with nZVI.

  17. Lung function profiles and aerobic capacity of adult cigarette and ...

    African Journals Online (AJOL)

    Lung function profiles and aerobic capacity of adult cigarette and hookah smokers after 12 weeks intermittent training. ... All subjects performed 30 min of interval exercise (2 min of work followed by 1 min of rest) three times a week for 12 weeks at an intensity estimated at 70% of the subject's maximum aerobic capacity ...

  18. Decrease in musculoskeletal pain after 4 and 12 months of an aerobic exercise intervention

    DEFF Research Database (Denmark)

    Korshøj, Mette; Birk Jørgensen, Marie; Lidegaard, Mark

    2018-01-01

    affects level of musculoskeletal pain from baseline to 4- and 12-months follow-up. METHODS: One-hundred-and-sixteen cleaners aged 18-65 years were cluster-randomized. The aerobic exercise group ( n = 57) received worksite aerobic exercise (30 min twice a week) and the reference group ( n = 59) lectures....... Aerobic exercise interventions among workers standing or walking in the majority of the working hours should tailor exercise to only maintain the positive effect on musculoskeletal pain.......BACKGROUND: Prevalence of musculoskeletal pain is high in jobs with high physical work demands. An aerobic exercise intervention targeting cardiovascular health was evaluated for its long term side effects on musculoskeletal pain. OBJECTIVE: The objective was to investigate if aerobic exercise...

  19. Disintegration of aerobic granules induced by trans-2-decenoic acid.

    Science.gov (United States)

    Cai, Pei-Jie; Xiao, Xiang; He, Yan-Rong; Li, Wen-Wei; Yu, Lei; Yu, Han-Qing

    2013-01-01

    One current major hurdle to practical implementation of aerobic granule technology is the frequent occurrence of granule disintegration during long-term operation. However, the mechanism behind this is largely unclear today. Here, 2-decenoic acid, which has been previously demonstrated to be released by Pseudomonas aeruginosa and disperse biofilms, was found to also induce the disintegration of aerobic granules. A comparison of the solution compositions from samples of only trans-2-decenoic acid, only aerobic granules, and granules added with trans-2-decenoic acid shows that bacteria and extracellular polymeric substances (EPS) were stripped from granule surface upon trans-2-decenoic acid dosing. Due to the possible toxicity of trans-2-decenoic acid at a saturation concentration, the disintegrated granules and the milky suspension in the disintegration test showed a significantly lower oxygen uptake rate than the un-integrated granules. This work suggests that trans-2-decenoic acid released by microbes might play a critical role in regulating the disintegration of aerobic granules. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Inherent aerobic capacity-dependent differences in breast carcinogenesis.

    Science.gov (United States)

    Thompson, Henry J; Jones, Lee W; Koch, Lauren G; Britton, Steven L; Neil, Elizabeth S; McGinley, John N

    2017-09-01

    Although regular physical activity is associated with improvement in aerobic capacity and lower breast cancer risk, there are heritable sets of traits that affect improvement in aerobic capacity in response to physical activity. Although aerobic capacity segregates risk for a number of chronic diseases, the effect of the heritable component on cancer risk has not been evaluated. Therefore, we investigated breast carcinogenesis in rodent models of heritable fitness in the absence of induced physical activity. Female offspring of N:NIH rats selectively bred for low (LIAC) or high (HIAC) inherent aerobic capacity were injected intraperitoneally with 1-methyl-1-nitrosurea (70 mg/kg body wt). At study termination 33 weeks post-carcinogen, cancer incidence (14.0 versus 47.3%; P < 0.001) and multiplicity (0.18 versus 0.85 cancers per rat; P < 0.0001) were significantly decreased in HIAC versus LIAC rats, respectively. HIAC had smaller visceral and subcutaneous body fat depots than LIAC and activity of two proteins that regulated the mammalian target of rapamycin, protein kinase B (Akt), and adenosine monophosphate-activated protein kinase were suppressed and activated, respectively, in HIAC. Although many factors distinguish between HIAC and LIAC, it appears that the protective effect of HIAC against breast carcinogenesis is mediated, at least in part, via alterations in core metabolic signaling pathways deregulated in the majority of human breast cancers. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Evaluation of Biodegradability of Waste Before and After Aerobic Treatment

    Science.gov (United States)

    Suchowska-Kisielewicz, Monika; Jędrczak, Andrzej; Sadecka, Zofia

    2014-12-01

    An important advantage of use of an aerobic biostabilization of waste prior to its disposal is that it intensifies the decomposition of the organic fraction of waste into the form which is easily assimilable for methanogenic microorganisms involved in anaerobic decomposition of waste in the landfill. In this article it is presented the influence of aerobic pre-treatment of waste as well as leachate recirculation on susceptibility to biodegradation of waste in anaerobic laboratory reactors. The research has shown that in the reactor with aerobically treated waste stabilized with recilculation conversion of the organic carbon into the methane is about 45% higher than in the reactor with untreated waste stabilized without recirculation.

  2. Tumor vessel normalization after aerobic exercise enhances chemotherapeutic efficacy.

    Science.gov (United States)

    Schadler, Keri L; Thomas, Nicholas J; Galie, Peter A; Bhang, Dong Ha; Roby, Kerry C; Addai, Prince; Till, Jacob E; Sturgeon, Kathleen; Zaslavsky, Alexander; Chen, Christopher S; Ryeom, Sandra

    2016-10-04

    Targeted therapies aimed at tumor vasculature are utilized in combination with chemotherapy to improve drug delivery and efficacy after tumor vascular normalization. Tumor vessels are highly disorganized with disrupted blood flow impeding drug delivery to cancer cells. Although pharmacologic anti-angiogenic therapy can remodel and normalize tumor vessels, there is a limited window of efficacy and these drugs are associated with severe side effects necessitating alternatives for vascular normalization. Recently, moderate aerobic exercise has been shown to induce vascular normalization in mouse models. Here, we provide a mechanistic explanation for the tumor vascular normalization induced by exercise. Shear stress, the mechanical stimuli exerted on endothelial cells by blood flow, modulates vascular integrity. Increasing vascular shear stress through aerobic exercise can alter and remodel blood vessels in normal tissues. Our data in mouse models indicate that activation of calcineurin-NFAT-TSP1 signaling in endothelial cells plays a critical role in exercise-induced shear stress mediated tumor vessel remodeling. We show that moderate aerobic exercise with chemotherapy caused a significantly greater decrease in tumor growth than chemotherapy alone through improved chemotherapy delivery after tumor vascular normalization. Our work suggests that the vascular normalizing effects of aerobic exercise can be an effective chemotherapy adjuvant.

  3. New Dimensions in Microbial Ecology—Functional Genes in Studies to Unravel the Biodiversity and Role of Functional Microbial Groups in the Environment

    Science.gov (United States)

    Imhoff, Johannes F.

    2016-01-01

    During the past decades, tremendous advances have been made in the possibilities to study the diversity of microbial communities in the environment. The development of methods to study these communities on the basis of 16S rRNA gene sequences analysis was a first step into the molecular analysis of environmental communities and the study of biodiversity in natural habitats. A new dimension in this field was reached with the introduction of functional genes of ecological importance and the establishment of genetic tools to study the diversity of functional microbial groups and their responses to environmental factors. Functional gene approaches are excellent tools to study the diversity of a particular function and to demonstrate changes in the composition of prokaryote communities contributing to this function. The phylogeny of many functional genes largely correlates with that of the 16S rRNA gene, and microbial species may be identified on the basis of functional gene sequences. Functional genes are perfectly suited to link culture-based microbiological work with environmental molecular genetic studies. In this review, the development of functional gene studies in environmental microbiology is highlighted with examples of genes relevant for important ecophysiological functions. Examples are presented for bacterial photosynthesis and two types of anoxygenic phototrophic bacteria, with genes of the Fenna-Matthews-Olson-protein (fmoA) as target for the green sulfur bacteria and of two reaction center proteins (pufLM) for the phototrophic purple bacteria, with genes of adenosine-5′phosphosulfate (APS) reductase (aprA), sulfate thioesterase (soxB) and dissimilatory sulfite reductase (dsrAB) for sulfur oxidizing and sulfate reducing bacteria, with genes of ammonia monooxygenase (amoA) for nitrifying/ammonia-oxidizing bacteria, with genes of particulate nitrate reductase and nitrite reductases (narH/G, nirS, nirK) for denitrifying bacteria and with genes of methane

  4. The Dark Side of the Mushroom Spring Microbial Mat: Life in the Shadow of Chlorophototrophs. II. Metabolic Functions of Abundant Community Members Predicted from Metagenomic Analyses.

    Science.gov (United States)

    Thiel, Vera; Hügler, Michael; Ward, David M; Bryant, Donald A

    2017-01-01

    Microbial mat communities in the effluent channels of Octopus and Mushroom Springs within the Lower Geyser Basin of Yellowstone National Park have been extensively characterized. Previous studies have focused on the chlorophototrophic organisms of the phyla Cyanobacteria and Chloroflexi . However, the diversity and metabolic functions of the other portion of the community in the microoxic/anoxic region of the mat are poorly understood. We recently described the diverse but extremely uneven microbial assemblage in the undermat of Mushroom Spring based on 16S rRNA amplicon sequences, which was dominated by Roseiflexus members, filamentous anoxygenic chlorophototrophs. In this study, we analyzed the orange-colored undermat portion of the community of Mushroom Spring mats in a genome-centric approach and discuss the metabolic potentials of the major members. Metagenome binning recovered partial genomes of all abundant community members, ranging in completeness from ~28 to 96%, and allowed affiliation of function with taxonomic identity even for representatives of novel and Candidate phyla. Less complete metagenomic bins correlated with high microdiversity. The undermat portion of the community was found to be a mixture of phototrophic and chemotrophic organisms, which use bicarbonate as well as organic carbon sources derived from different cell components and fermentation products. The presence of rhodopsin genes in many taxa strengthens the hypothesis that light energy is of major importance. Evidence for the usage of all four bacterial carbon fixation pathways was found in the metagenome. Nitrogen fixation appears to be limited to Synechococcus spp. in the upper mat layer and Thermodesulfovibrio sp. in the undermat, and nitrate/nitrite metabolism was limited. A closed sulfur cycle is indicated by biological sulfate reduction combined with the presence of genes for sulfide oxidation mainly in phototrophs. Finally, a variety of undermat microorganisms have genes for

  5. The Dark Side of the Mushroom Spring Microbial Mat: Life in the Shadow of Chlorophototrophs. II. Metabolic Functions of Abundant Community Members Predicted from Metagenomic Analyses

    Directory of Open Access Journals (Sweden)

    Vera Thiel

    2017-06-01

    Full Text Available Microbial mat communities in the effluent channels of Octopus and Mushroom Springs within the Lower Geyser Basin of Yellowstone National Park have been extensively characterized. Previous studies have focused on the chlorophototrophic organisms of the phyla Cyanobacteria and Chloroflexi. However, the diversity and metabolic functions of the other portion of the community in the microoxic/anoxic region of the mat are poorly understood. We recently described the diverse but extremely uneven microbial assemblage in the undermat of Mushroom Spring based on 16S rRNA amplicon sequences, which was dominated by Roseiflexus members, filamentous anoxygenic chlorophototrophs. In this study, we analyzed the orange-colored undermat portion of the community of Mushroom Spring mats in a genome-centric approach and discuss the metabolic potentials of the major members. Metagenome binning recovered partial genomes of all abundant community members, ranging in completeness from ~28 to 96%, and allowed affiliation of function with taxonomic identity even for representatives of novel and Candidate phyla. Less complete metagenomic bins correlated with high microdiversity. The undermat portion of the community was found to be a mixture of phototrophic and chemotrophic organisms, which use bicarbonate as well as organic carbon sources derived from different cell components and fermentation products. The presence of rhodopsin genes in many taxa strengthens the hypothesis that light energy is of major importance. Evidence for the usage of all four bacterial carbon fixation pathways was found in the metagenome. Nitrogen fixation appears to be limited to Synechococcus spp. in the upper mat layer and Thermodesulfovibrio sp. in the undermat, and nitrate/nitrite metabolism was limited. A closed sulfur cycle is indicated by biological sulfate reduction combined with the presence of genes for sulfide oxidation mainly in phototrophs. Finally, a variety of undermat

  6. New Dimensions in Microbial Ecology—Functional Genes in Studies to Unravel the Biodiversity and Role of Functional Microbial Groups in the Environment

    Directory of Open Access Journals (Sweden)

    Johannes F. Imhoff

    2016-05-01

    Full Text Available During the past decades, tremendous advances have been made in the possibilities to study the diversity of microbial communities in the environment. The development of methods to study these communities on the basis of 16S rRNA gene sequences analysis was a first step into the molecular analysis of environmental communities and the study of biodiversity in natural habitats. A new dimension in this field was reached with the introduction of functional genes of ecological importance and the establishment of genetic tools to study the diversity of functional microbial groups and their responses to environmental factors. Functional gene approaches are excellent tools to study the diversity of a particular function and to demonstrate changes in the composition of prokaryote communities contributing to this function. The phylogeny of many functional genes largely correlates with that of the 16S rRNA gene, and microbial species may be identified on the basis of functional gene sequences. Functional genes are perfectly suited to link culture-based microbiological work with environmental molecular genetic studies. In this review, the development of functional gene studies in environmental microbiology is highlighted with examples of genes relevant for important ecophysiological functions. Examples are presented for bacterial photosynthesis and two types of anoxygenic phototrophic bacteria, with genes of the Fenna-Matthews-Olson-protein (fmoA as target for the green sulfur bacteria and of two reaction center proteins (pufLM for the phototrophic purple bacteria, with genes of adenosine-5′phosphosulfate (APS reductase (aprA, sulfate thioesterase (soxB and dissimilatory sulfite reductase (dsrAB for sulfur oxidizing and sulfate reducing bacteria, with genes of ammonia monooxygenase (amoA for nitrifying/ammonia-oxidizing bacteria, with genes of particulate nitrate reductase and nitrite reductases (narH/G, nirS, nirK for denitrifying bacteria and with genes

  7. The Acute Effect of Aerobic Exercise on Measures of Stress.

    Science.gov (United States)

    Fort, Inza L.; And Others

    The immediate response of stress to aerobic exercise was measured by utilizing the Palmar Sweat Index (PSI) and the State-Trait Anxiety Inventory (STAI). Forty subjects (20 male and 20 female) from the ages of 18-30 sustained a single bout of aerobic activity for 30 minutes at 60 percent of their maximum heart rate. Pre-treatment procedures…

  8. Radiosensitivity of bacteriophages of aerobic spore-forming microorganisms

    International Nuclear Information System (INIS)

    Polkhovskij, V.A.

    1978-01-01

    Under conditions of direct radiation effect on seven original phages of aerobic sporeforming bacteria and four standard phages of E. coli it has been established, that all of them had different sensitivity to gamma radiation and were divided into four groups. The phages of E. coli of T series and in particular the T2 phage turned out the most sensitive. The phages of aerobic sporeforming bacilli were more resistant to gamma radiation effect, which is connected, apparently, with a lower DNA content in phages of Bacillus in comparison with the T phages

  9. Effects of aerobic activity on serum IgG concentration in male physical education students

    Directory of Open Access Journals (Sweden)

    Arshadi Arshadi

    2012-12-01

    Full Text Available The aim of this study was to investigate the effects of aerobic activity on Serum IgG concentration. Consequently, 10 male physical education students with age ranging from 21 to 24 years old and mean body mass index 22.22 kg m2 volunteered to participate in this study. Aerobic activity was performed on bicycle ergometer for 30 minutes at intensity of 70 to 75 percent of maximum heart rate. Blood samples were obtained from subjects before and after aerobic activity. Changes in serum IgG concentration in pre-test and post-test were analyzed by dependent t-test using spss software. The results showed that aerobic activity not significantly effect on Serum IgG concentration (p=0.357. This study concludes that sub maximal aerobic activity does not affect on serum IgG concentration and there is no concern for athletes and coaches that sub maximal aerobic activity can impair immune function.

  10. Characterization of novel bacteriochlorophyll-a-containing red filaments from alkaline hot springs in Yellowstone National Park.

    Science.gov (United States)

    Boomer, S M; Pierson, B K; Austinhirst, R; Castenholz, R W

    2000-09-01

    Novel red, filamentous, gliding bacteria formed deep red layers in several alkaline hot springs in Yellowstone National Park. Filaments contained densely layered intracellular membranes and bacteriochlorophyll a. The in vivo absorption spectrum of the red layer filaments was distinct from other phototrophs, with unusual bacteriochlorophyll a signature peaks in the near-infrared (IR) region (807 nm and 911 nm). These absorption peaks were similar to the wavelengths penetrating to the red layer of the mats as measured with in situ spectroradiometry. The filaments also demonstrated maximal photosynthetic uptake of radiolabeled carbon sources at these wavelengths. The red layer filaments displayed anoxygenic photoheterotrophy, as evidenced by the specific incorporation of acetate, not bicarbonate, and by the absence of oxygen production. Photoheterotrophy was unaffected by sulfide and oxygen, but was diminished by high-intensity visible light. Near-IR radiation supported photoheterotrophy. Morphologically and spectrally similar filaments were observed in several springs in Yellowstone National Park, including Octopus Spring. Taken together, these data suggest that the red layer filaments are most similar to the photoheterotroph, Heliothrix oregonensis. Notable differences include mat position and coloration, absorption spectra, and prominent intracellular membranes.

  11. Potential and limits of Raman spectroscopy for carotenoid detection in microorganisms: implications for astrobiology

    Science.gov (United States)

    Jehlička, Jan; Edwards, Howell G. M.; Osterrothová, Kateřina; Novotná, Julie; Nedbalová, Linda; Kopecký, Jiří; Němec, Ivan; Oren, Aharon

    2014-01-01

    In this paper, it is demonstrated how Raman spectroscopy can be used to detect different carotenoids as possible biomarkers in various groups of microorganisms. The question which arose from previous studies concerns the level of unambiguity of discriminating carotenoids using common Raman microspectrometers. A series of laboratory-grown microorganisms of different taxonomic affiliation was investigated, such as halophilic heterotrophic bacteria, cyanobacteria, the anoxygenic phototrophs, the non-halophilic heterotrophs as well as eukaryotes (Ochrophyta, Rhodophyta and Chlorophyta). The data presented show that Raman spectroscopy is a suitable tool to assess the presence of carotenoids of these organisms in cultures. Comparison is made with the high-performance liquid chromatography approach of analysing pigments in extracts. Direct measurements on cultures provide fast and reliable identification of the pigments. Some of the carotenoids studied are proposed as tracers for halophiles, in contrast with others which can be considered as biomarkers of other genera. The limits of application of Raman spectroscopy are discussed for a few cases where the current Raman spectroscopic approach does not allow discriminating structurally very similar carotenoids. The database reported can be used for applications in geobiology and exobiology for the detection of pigment signals in natural settings. PMID:25368348

  12. Isolation and Characterization of Aerobic Denitrifiers from Agricultural Soil

    OpenAIRE

    ÇELEN, Ebru; KILIÇ, Mehmet Akif

    2004-01-01

    Denitrification is generally considered an anaerobic process. However, in recent years it has been shown that bacteria can also reduce nitrate to nitrite under aerobic conditions. The characterization of biologically available nitrogen forms and their biological cycling mechanisms is important for ecological and agricultural implications. In this study, aerobic nitrate reducers were isolated from greenhouse soil. Using a nitrate reduction assay, it was found that 39 out of 60 isolates can red...

  13. EFFECT OF HIGH & LOW INTENSITIES OF AEROBIC EXERCISE ON PHYSICAL FITNESS INDEX

    Directory of Open Access Journals (Sweden)

    Madhusudhan

    2015-06-01

    Full Text Available BACKGROUND: Aerobic exercise reduces body fat and improves weight control, increases HDL&Vo2 max. Also improves PFI (physical fitness index which is defined as ability to carry out daily tasks with vigour and alertness without undue fatigue. Though aerobic exercise is found to improve physical fitness, the relative merits of different intensities of aerobi c exercise in improving physical fitness is still uncertain. AIM: The present study was conducted to know the Effect of High & low intensity aerobic training on physical fitness index. MATERIALS & METHODS : 80 sedentary men (18 - 40 years were randomized in to 2 equal groups (High Intensity & low intensity group . The High [80% HR max] & Low intensity [50 % HR max] groups underwent aerobic exercise training using Bicycle ergo meter (COSCO at 900kpm & 540kpm, for 15mins/day & 30mins/day respectively, 5days a week, for a period of 14weeks. Physical fitness index of each subject was recorded by Modified Harvard step test before & after intervention. RESULTS : After 14 weeks of aerobic training both the exercise groups had improvement in PFI, but high intensity gr oup had a significant (p<0.05 improvement in PFI (97.18 - 101.14 than low intensity group (98.12 - 100.6. CONCLUSION : High intensity aerobic exercise is effective in improving physical fitness.

  14. Performance and diversity of polyvinyl alcohol-degrading bacteria under aerobic and anaerobic conditions.

    Science.gov (United States)

    Huang, Jianping; Yang, Shisu; Zhang, Siqi

    2016-11-01

    To compare the degradation performance and biodiversity of a polyvinyl alcohol-degrading microbial community under aerobic and anaerobic conditions. An anaerobic-aerobic bioreactor was operated to degrade polyvinyl alcohol (PVA) in simulated wastewater. The degradation performance of the bioreactor during sludge cultivation and the microbial communities in each reactor were compared. Both anaerobic and aerobic bioreactors demonstrated high chemical oxygen demand removal efficiencies of 87.5 and 83.6 %, respectively. Results of 16S rDNA sequencing indicated that Proteobacteria dominated in both reactors and that the microbial community structures varied significantly under different operating conditions. Both reactors obviously differed in bacterial diversity from the phyla Planctomycetes, Chlamydiae, Bacteroidetes, and Chloroflexi. Betaproteobacteria and Alphaproteobacteria dominated, respectively, in the anaerobic and aerobic reactors. The anaerobic-aerobic system is suitable for PVA wastewater treatment, and the microbial genetic analysis may serve as a reference for PVA biodegradation.

  15. Biodegradation of bilge water: Batch test under anaerobic and aerobic conditions and performance of three pilot aerobic Moving Bed Biofilm Reactors (MBBRs) at different filling fractions.

    Science.gov (United States)

    Vyrides, Ioannis; Drakou, Efi-Maria; Ioannou, Stavros; Michael, Fotoula; Gatidou, Georgia; Stasinakis, Athanasios S

    2018-07-01

    The bilge water that is stored at the bottom of the ships is saline and greasy wastewater with a high Chemical Oxygen Demand (COD) fluctuations (2-12 g COD L -1 ). The aim of this study was to examine at a laboratory scale the biodegradation of bilge water using first anaerobic granular sludge followed by aerobic microbial consortium (consisted of 5 strains) and vice versa and then based on this to implement a pilot scale study. Batch results showed that granular sludge and aerobic consortium can remove up to 28% of COD in 13 days and 65% of COD removal in 4 days, respectively. The post treatment of anaerobic and aerobic effluent with aerobic consortium and granular sludge resulted in further 35% and 5% COD removal, respectively. The addition of glycine betaine or nitrates to the aerobic consortium did not enhance significantly its ability to remove COD from bilge water. The aerobic microbial consortium was inoculated in 3 pilot (200 L) Moving Bed Biofilm Reactors (MBBRs) under filling fractions of 10%, 20% and 40% and treated real bilge water for 165 days under 36 h HRT. The MBBR with a filling fraction of 40% resulted in the highest COD decrease (60%) compared to the operation of the MBBRs with a filling fraction of 10% and 20%. GC-MS analysis on 165 day pointed out the main organic compounds presence in the influent and in the MBBR (10% filling fraction) effluent. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Isoprenoid quinones resolve the stratification of microbial redox processes in a biogeochemical continuum from the photic zone to deep anoxic sediments of the Black Sea.

    Science.gov (United States)

    Becker, Kevin W; Elling, Felix J; Schröder, Jan M; Lipp, Julius S; Goldhammer, Tobias; Zabel, Matthias; Elvert, Marcus; Overmann, Jörg; Hinrichs, Kai-Uwe

    2018-03-09

    The stratified water column of the Black Sea serves as a model ecosystem for studying the interactions of microorganisms with major biogeochemical cycles. Here we provide detailed analysis of isoprenoid quinones to study microbial redox processes in the ocean. In a continuum from the photic zone through the chemocline into deep anoxic sediments of the southern Black Sea, diagnostic quinones and inorganic geochemical parameters indicate niche segregation between redox processes and corresponding shifts in microbial community composition. Quinones specific for oxygenic photosynthesis and aerobic respiration dominate oxic waters, while quinones associated with thaumarchaeal ammonia-oxidation and bacterial methanotrophy, respectively, dominate a narrow interval in suboxic waters. Quinone distributions indicate highest metabolic diversity within the anoxic zone, with anoxygenic photosynthesis being a major process in its photic layer. In the dark anoxic layer, quinone profiles indicate occurrence of bacterial sulfur and nitrogen cycling, archaeal methanogenesis, and archaeal methanotrophy. Multiple novel ubiquinone isomers, possibly originating from unidentified intra-aerobic anaerobes, occur in this zone. The respiration modes found in the anoxic zone continue into shallow subsurface sediments, but quinone abundances rapidly decrease within the upper 50 cm below sea floor, reflecting the transition to lower energy availability. In the deep subseafloor sediments, quinone distributions and geochemical profiles indicate archaeal methanogenesis/methanotrophy and potentially bacterial fermentative metabolisms. We observed that sedimentary quinone distributions track lithology, which supports prior hypotheses that deep biosphere community composition and metabolisms are determined by environmental conditions during sediment deposition. Importance Microorganisms play crucial roles in global biogeochemical cycles. Yet, we have only a fragmentary understanding of the diversity

  17. Height, Weight, and Aerobic Fitness Level in Relation to the Risk of Atrial Fibrillation.

    Science.gov (United States)

    Crump, Casey; Sundquist, Jan; Winkleby, Marilyn A; Sundquist, Kristina

    2018-03-01

    Tall stature and obesity have been associated with a higher risk of atrial fibrillation (AF), but there have been conflicting reports of the effects of aerobic fitness. We conducted a national cohort study to examine interactions between height or weight and level of aerobic fitness among 1,547,478 Swedish military conscripts during 1969-1997 (97%-98% of all 18-year-old men) in relation to AF identified from nationwide inpatient and outpatient diagnoses through 2012 (maximal age, 62 years). Increased height, weight, and aerobic fitness level (but not muscular strength) at age 18 years were all associated with a higher AF risk in adulthood. Positive additive and multiplicative interactions were found between height or weight and aerobic fitness level (for the highest tertiles of height and aerobic fitness level vs. the lowest, relative excess risk = 0.51, 95% confidence interval (CI): 0.40, 0.62; ratio of hazard ratios = 1.50, 95% CI: 1.34, 1.65). High aerobic fitness levels were associated with higher risk among men who were at least 186 cm (6 feet, 1 inch) tall but were protective among shorter men. Men with the combination of tall stature and high aerobic fitness level had the highest risk (for the highest tertiles vs. the lowest, adjusted hazard ratio = 1.70, 95% CI: 1.61, 1.80). These findings suggest important interactions between body size and aerobic fitness level in relation to AF and may help identify high-risk subgroups.

  18. Validation of the FAST skating protocol to predict aerobic power in ice hockey players.

    Science.gov (United States)

    Petrella, Nicholas J; Montelpare, William J; Nystrom, Murray; Plyley, Michael; Faught, Brent E

    2007-08-01

    Few studies have reported a sport-specific protocol to measure the aerobic power of ice hockey players using a predictive process. The purpose of our study was to validate an ice hockey aerobic field test on players of varying ages, abilities, and levels. The Faught Aerobic Skating Test (FAST) uses an on-ice continuous skating protocol on a course measuring 160 feet (48.8 m) using a CD to pace the skater with a beep signal to cross the starting line at each end of the course. The FAST incorporates the principle of increasing workload at measured time intervals during a continuous skating exercise. Step-wise multiple regression modelling was used to determine the estimate of aerobic power. Participants completed a maximal aerobic power test using a modified Bruce incremental treadmill protocol, as well as the on-ice FAST. Normative data were collected on 406 ice hockey players (291 males, 115 females) ranging in age from 9 to 25 y. A regression to predict maximum aerobic power was developed using body mass (kg), height (m), age (y), and maximum completed lengths of the FAST as the significant predictors of skating aerobic power (adjusted R2 = 0.387, SEE = 7.25 mL.kg-1.min-1, p < 0.0001). These results support the application of the FAST in estimating aerobic power among male and female competitive ice hockey players between the ages of 9 and 25 years.

  19. Cardiac Frequency and Caloric Cost of Aerobic Dancing in Young Women.

    Science.gov (United States)

    Nelson, Deborah J.; And Others

    1988-01-01

    A study of cardiac frequency during aerobic dancing indicated that it can sustain an elevated cardiac frequency in most cases. The caloric cost of aerobic dancing is approximately 50 percent greater than an equal duration of barre and center-floor exercise by elite ballet dancers. (JD)

  20. Aerobic exercise and other healthy lifestyle factors that influence vascular aging

    Science.gov (United States)

    Santos-Parker, Jessica R.; LaRocca, Thomas J.

    2014-01-01

    Cardiovascular diseases (CVDs) remain the leading cause of death in the United States and other modern societies. Advancing age is the major risk factor for CVD, primarily due to stiffening of the large elastic arteries and the development of vascular endothelial dysfunction. In contrast, regular aerobic exercise protects against the development of large elastic artery stiffness and vascular endothelial dysfunction with advancing age. Moreover, aerobic exercise interventions reduce arterial stiffness and restore vascular endothelial function in previously sedentary middle-aged/older adults. Aerobic exercise exerts its beneficial effects on arterial function by modulating structural proteins, reducing oxidative stress and inflammation, and restoring nitric oxide bioavailability. Aerobic exercise may also promote “resistance” against factors that reduce vascular function and increase CVD risk with age. Preventing excessive increases in abdominal adiposity, following healthy dietary practices, maintaining a low CVD risk factor profile, and, possibly, selective use of pharmaceuticals and nutraceuticals also play a major role in preserving vascular function with aging. PMID:25434012

  1. Aerobic exercise and other healthy lifestyle factors that influence vascular aging.

    Science.gov (United States)

    Santos-Parker, Jessica R; LaRocca, Thomas J; Seals, Douglas R

    2014-12-01

    Cardiovascular diseases (CVDs) remain the leading cause of death in the United States and other modern societies. Advancing age is the major risk factor for CVD, primarily due to stiffening of the large elastic arteries and the development of vascular endothelial dysfunction. In contrast, regular aerobic exercise protects against the development of large elastic artery stiffness and vascular endothelial dysfunction with advancing age. Moreover, aerobic exercise interventions reduce arterial stiffness and restore vascular endothelial function in previously sedentary middle-aged/older adults. Aerobic exercise exerts its beneficial effects on arterial function by modulating structural proteins, reducing oxidative stress and inflammation, and restoring nitric oxide bioavailability. Aerobic exercise may also promote "resistance" against factors that reduce vascular function and increase CVD risk with age. Preventing excessive increases in abdominal adiposity, following healthy dietary practices, maintaining a low CVD risk factor profile, and, possibly, selective use of pharmaceuticals and nutraceuticals also play a major role in preserving vascular function with aging. Copyright © 2014 The American Physiological Society.

  2. Condensed tannins affect bacterial and fungal microbiomes and mycotoxin production during ensiling and upon aerobic exposure.

    Science.gov (United States)

    Peng, Kai; Jin, Long; Niu, Yan D; Huang, Qianqian; McAllister, Tim A; Yang, Hee Eun; Denise, Hubert; Xu, Zhongjun; Acharya, Surya; Wang, Shunxi; Wang, Yuxi

    2017-12-15

    Purple prairie clover (PPC; Dalea purpurea Vent.) containing 84.5 g/kg DM of condensed tannin (CT) was ensiled without (Control) or with polyethylene glycol (PEG) for 76 days, followed by 14 days of aerobic exposure. Changes in fermentation characteristics were determined and bacterial and fungal communities were assessed using metagenomic sequencing. Addition of PEG that deactivated CT at ensiling increased ( P aerobic exposure. The PEG treated silage exhibited higher ( P aerobic exposure, whereas it increased ( P aerobic exposure. Addition of PEG at ensiling increased ( P aerobic exposure, whereas the Bacillus were the dominate bacteria after aerobic exposure. In conclusion, CT decreased protein degradation and improved aerobic stability of silage. These desirable outcomes likely reflect the ability of PPC CT to inhibit those microorganisms involved in lowering silage quality and in the production of mycotoxins. IMPORTANCE The present study reports the effects of condensed tannins on the complex microbial communities involved in ensiling and aerobic exposure of purple prairie clover. This study documents the ability of condensed tannins to lower mycotoxin production and associated microbiome. Taxonomic bacterial community profiles were dominated by the Lactobacillales after fermentation, with a notable increase in Bacillus as a result of aerobic exposure. It is interesting to observe that condensed tannins decreased bacterial diversity during both ensiling and aerobic exposure but increased fungal diversity during aerobic exposure only. The present study indicates that the effects of condensed tannins on microbial communities lead to a reduced lactic acid and total volatile fatty acids production, proteolysis and mycotoxin concentration in the terminal silage and an improved aerobic stability. Condensed tannins could be used as additive to control unfavorable microbial development and maybe enhanced feed safety. © Crown copyright 2017.

  3. Identifikasi Dan Uji Kepekaan Kuman Aerob Pada Alpeolitis Pascapencabutan Gigi

    OpenAIRE

    Rehatta Yongki, Dr.med.dent

    2002-01-01

    Dosen Pada Bagian Konservasi dan Bedah Mulut FKG Unhas Penelitian ini bertujuan untuk mengidentifikasi kuman aerob yang dominan pada alveolitis pascapencabutan gigi dan untuk mengetahui perbedaan kepekaan kuman aerob yang dominan dari Alveolitis terhadap beberapa antiobiotik. Penelitian ini merupakan jenis penelitian deskriftif dan uji laboratorium. Sampel sebanyak 32 orang yang diambil secara Purpose Sampling. Soket diteliti secara cermat, dilakukan pengambilan usapan . Untuk mengiden...

  4. EFFECTIVENES OF AEROBIC AND YOGA EXERCISE TO INCREASE CARDIORESPIRATION STAMINA IN CARIER WOMEN

    Directory of Open Access Journals (Sweden)

    Esti Yunitasari

    2017-07-01

    Full Text Available Introduction : Cardiorespiratory endurance is one of the components of fitness. Cardiorespiratory endurance is considered to have relation with health because the low grade of fitness connected to high risk of immature death especially cardiovascular disease. Sport such as aerobic exercise and yoga exercise is one of efforts to increase cardiorespiratory endurance. This study was aimed to analyze the effectiveness aerobic exercise and yoga exercise to increase of cardiorespiratory endurance in female employee. Method : The design of the study was Quasy Experimental by using non-probability sampling (purposive sampling. Total sample of this study were 21 respondents. Seven respondents as treatment aerobic exerciser, 7 respondents as treatment yoga exerciser and 7 respondents as control group. The independent variables were aerobic exercise and yoga exercise. The dependent variables were the increase cardiorespiratory endurance. The data were collected and analyzed by using paired t test and anova with significance level a < 0,05. Result : The result showed that there were no differences effectiveness aerobic exercise and yoga exercise to increase cardiorespiratory endurance for female employee which were indicated by pulse (p=0,388, blood pressure systole (p= 0,520, blood pressure diastole (p=0,131 and respiration (p=0,432. Analysis :  It can be concluded that both of gymnastic aerobic and yoga effective on increasing immunity of cardiovascular for the female. Discussion : Female employee can consider aerobic and yoga as an effort to increase cardiorespiratory endurance.

  5. Durations and domains of daily aerobic activity: evidence from the 2010 Canadian time-use survey.

    Science.gov (United States)

    Millward, Hugh; Spinney J, E L; Scott, Darren

    2014-07-01

    This study employs national time-diary data to evaluate how much aerobic activity Canadians engage in on a daily basis, how that activity is apportioned by activity domain, and how subgroups within the population vary in their aerobic attainment. The study employs time-use data from the 2010 General Social Survey of Canada, for 15,390 respondents aged 15 and older. To estimate effort levels, the authors harmonized survey codes with those in the Compendium of Physical Activities. Aerobic activity was defined as moderate or vigorous effort at 3.5 Metabolic Equivalent of Task (MET) or higher. Among the 4 activity domains, aerobic participation is highest in leisure activities, followed by chores, paid work, and active transportation (AT). Only a minority (42%) of respondents recorded at least 20 mins/day of aerobic activity. Aerobic totals were particularly low for women and those in poor or fair health, and low for students, 15- to 24-year-olds, and those residing in Quebec, Ontario, and larger cities. The majority of Canadian adults are failing to meet recommended aerobic activity levels. However, there is considerable opportunity to increase aerobic participation for some groups, particularly women and young adults, especially in the leisure and AT domains.

  6. Pathogen inactivation in liquid dairy manure during anaerobic and aerobic digestions

    Science.gov (United States)

    Biswas, S.; Pandey, P.; Castillo, A. R.; Vaddella, V. K.

    2014-12-01

    Controlling manure-borne pathogens such as E. coli O157:H7, Salmonella spp. and Listeria monocytogenes are crucial for protecting surface and ground water as well as mitigating risks to human health. In California dairy farms, flushing of dairy manure (mainly animal feces and urine) from freestall barns and subsequent liquid-solid manure separation is a common practice for handling animal waste. The liquid manure fraction is generally pumped into the settling ponds and it goes into aerobic and/or anaerobic lagoons for extended period of time. Considering the importance of controlling pathogens in animal waste, the objective of the study was to understand the effects of anaerobic and aerobic digestions on the survival of three human pathogens in animal waste. The pathogen inactivation was assessed at four temperatures (30, 35, 42, and 50 °C), and the relationships between temperature and pathogen decay were estimated. Results showed a steady decrease of E. coli levels in aerobic and anaerobic digestion processes over the time; however, the decay rates varied with pathogens. The effect of temperature on Salmonella spp. and Listeria monocytogenes survival was different than the E. coli survival. In thermophilic temperatures (42 and 50 °C), decay rate was considerable greater compared to the mesophilic temperatures (30 and 35°C). The E. coli log reductions at 50 °C were 2.1 in both aerobic and anaerobic digestions after 13 days of incubation. The Salmonella spp. log reductions at 50 °C were 5.5 in aerobic digestion, and 5.9 in anaerobic digestion. The Listeria monocytogenes log reductions at 50 °C were 5.0 in aerobic digestion, and 5.6 in anaerobic digestion. The log reduction of E. coli, Salmonella spp., and Listeria monocytogens at 30 °C in aerobic environment were 0.1, 4.7, and 5.6, respectively. In anaerobic environment, the corresponding reductions were 0.4, 4.3, and 5.6, respectively. We anticipate that the outcomes of the study will help improving the

  7. Anaerobic-aerobic biological treatment of a mixture of cheese whey and dairy manure

    Energy Technology Data Exchange (ETDEWEB)

    Lo, K.V.; Liao, P.H.

    1989-01-01

    The integrated anaerobic-aerobic biological treatment system consisted of an anaerobic rotating biological reactor and an aerobic sequencing batch reactor. Three sequencing batch reactors were used in the aerobic process. A mixture of cheese whey and dairy manure was successfully digested in an anaerobic rotating biological contactor which served as a first step in the waste treatment process. The methane production rate, which is dependent on the organic loading rate, ranged between 1.43 and 3.74 litres methane per litre reactor per day. As the organic loading rate increased, total methane production also increased. In the anaerobic digestion step, over 46% of chemical oxygen demand was removed. The potential pollutants were further destroyed by the aerobic treatment. More than 93% of the remaining chemical oxygen demand was removed in the sequencing batch reactors operated at 22/sup 0/C. The treatment efficiency was lower for the aerobic reactor operated at a lower temperature (10/sup 0/C). (author).

  8. Moderate-intensity aerobic exercise improves sleep quality in men older adults

    Directory of Open Access Journals (Sweden)

    Shams Amir

    2013-01-01

    Full Text Available The purpose of present research was to investigate the effect of low and moderate intensity aerobic exercises on sleep quality in older adults. The statistical sample included 45 volunteer elderly men with age range of 60-70 years old that divided randomly in two experimental groups (aerobic exercise with low and moderate intensity and one control group. The maximum heart rate (MaxHR of subjects was obtained by subtracting one's age from 220. Furthermore, based on aerobic exercise type (40-50% MaxHR for low intensity group and 60-70% MaxHR for moderate intensity group the target MaxHR was calculated for each subject. The exercise protocol consisted of 8 weeks aerobic exercises (2 sessions in per-week based on Rockport one-mile walking/running test and the control group continued their daily activities. All subjects in per-test and post-test stages were completed the Petersburg Sleep Quality Index (PSQI. Results in post-test stage showed that there were significant differences between control and experimental groups in sleep quality and its components (P<0.05. Also, the Tukey Post Hoc showed that the moderate intensity group scores in sleep quality and its components were better than other groups (P<0.05. Finally, the low intensity group scores were better than control group (P<0.05. Generally, the present research showed that the aerobic exercises with moderate intensity have a positive and significant effect on sleep quality and its components. Thus, based on these findings, the moderate intensity aerobic exercises as a useful and medical method for improve the sleep quality among community older adults was recommended.

  9. Diagnosis of aerobic vaginitis by quantitative real-time PCR.

    Science.gov (United States)

    Rumyantseva, T A; Bellen, G; Savochkina, Y A; Guschin, A E; Donders, G G G

    2016-07-01

    To evaluate a real-time PCR-based technique to quantify bacteria associated with aerobic vaginitis (AV) as a potential test. Vaginal samples from 100 women were tested by wet-mount microscopy, gram stain and quantitative real-time PCR targeting Enterobacteriacea, Staphylococcus spp., Streptococcus spp., Enterococcus spp., Escherichia coli, Streptococcus agalactiae, S. aureus; Lactobacillus spp. AV diagnosis obtained by wet-mount microscopy was used as reference. Some level of AV was diagnosed in 23 (23.7 %) cases. Various concentrations of Enterobacteriacea, Staphylococcus spp., Streptococcus spp. were detected an all patients. Enterococcus spp. were detected in 76 (78.3 %) cases. Summarized concentrations of aerobes were tenfold higher in AV-positive compared to AV-negative cases [7.30lg vs 6.06lg (p = 0.02)]. Concentrations of aerobes in severe, moderate and light AV cases did not vary significantly (p = 0.14). Concentration of lactobacilli was 1000-fold lower in AV-positive cases compared to normal cases (5.3lg vs 8.3lg, p AV-positive cases [19/22 (86.4 %) samples]. The relation of high loads of aerobes to the low numbers of Lactobacilli are a reliable marker for the presence of AV and could substitute microscopy as a test. PCR may be a good standardized substitution for AV diagnosis in settings where well-trained microscopists are lacking.

  10. Aerobic-synergized exercises may improve fall-related physical fitness in older adults.

    Science.gov (United States)

    Chang, Yu-Chen; Wang, Jung-Der; Chen, Ho-Cheng; Hu, Susan C

    2017-05-01

    The purpose of the present study was to determine whether a synergistic exercise model based on aerobics with additional fall-preventive components could provide extra benefits compared with the same duration of aerobic-synergistic exercise alone. A total of 102 adults aged 65 years and over from three geographically separated communities were assigned to three groups: the general aerobic exercise (GAE) group (N.=44), the GAE plus ball game group (BG group; N.=30) and the GAE plus square-stepping exercise group (SSE group; N.=28). Each group participated in one hour of exercise intervention and two hours of leisure activities twice weekly for 12 weeks. Each exercise session consisted of one hour of combined exercises performed in the following order: 10 minutes of warm-up activities, 20 minutes of aerobics, 20 minutes of the respective exercise model, and 10 minutes of cool-down activities. Functional fitness tests, including aerobic endurance, leg strength, flexibility, reaction time, static balance and mobility, were measured before and after the intervention. Paired t-tests and mixed model analyses were conducted to compare the differences in each measurement within and among the groups. All of the groups exhibited significantly positive effects (Pfall-prevention exercises performed over a consistent period may improve mobility without compromising the fundamental benefits of aerobics. Future studies using randomized control trials with recorded fall events and a longer period of follow-up are indicated to validate the effects of fall prevention exercises.

  11. Exercise therapy improves aerobic capacity of inpatients with major depressive disorder.

    Science.gov (United States)

    Kerling, Arno; von Bohlen, Anne; Kück, Momme; Tegtbur, Uwe; Grams, Lena; Haufe, Sven; Gützlaff, Elke; Kahl, Kai G

    2016-06-01

    Unipolar depression is one of the most common diseases worldwide and is associated with a higher cardiovascular risk partly due to reduced aerobic capacity. Therefore, the aim of our study was to examine whether a structured aerobic training program can improve aerobic capacity in inpatients with MDD (major depressive disorder). Overall, 25 patients (13 women, 12 men) diagnosed with MDD were included in the study. Parameters of aerobic capacity, such as maximum performance, maximum oxygen consumption, and VAT (ventilatory anaerobic threshold), were assessed on a bicycle ergometer before and 6 weeks after a training period (three times per week for 45 min on two endurance machines). In addition, a constant load test was carried out at 50% of the maximum performance prior to and after the training period. The performance data were compared with 25 healthy controls matched for sex, age, and body mass index before and after the training period. Compared to controls, patients with MDD had significantly lower aerobic capacity. After training, there was a significant improvement in their performance data. A significant difference remained only for VAT between patients with MDD and healthy controls. With regard to the coincidence of MDD with cardiovascular and cardiometabolic disorders, a structured supervised exercise program carried out during hospitalization is a useful supplement for patients with MDD.

  12. The influence of aerobic fitness status on ventilatory efficiency in patients with coronary artery disease

    Directory of Open Access Journals (Sweden)

    Danilo M.L. Prado

    2015-01-01

    Full Text Available OBJECTIVE: To test the hypotheses that 1 coronary artery disease patients with lower aerobic fitness exhibit a lower ventilatory efficiency and 2 coronary artery disease patients with lower initial aerobic fitness exhibit greater improvements in ventilatory efficiency with aerobic exercise training. METHOD: A total of 123 patients (61.0±0.7 years with coronary artery disease were divided according to aerobic fitness status into 3 groups: group 1 (n = 34, peak VO217.5 and 24.5 ml/kg/min. All patients performed a cardiorespiratory exercise test on a treadmill. Ventilatory efficiency was determined by the lowest VE/VCO2 ratio observed. The exercise training program comprised moderate-intensity aerobic exercise performed 3 times per week for 3 months. Clinicaltrials.gov: NCT02106533 RESULTS: Before intervention, group 1 exhibited both lower peak VO2 and lower ventilatory efficiency compared with the other 2 groups (p<0.05. After the exercise training program, group 1 exhibited greater improvements in aerobic fitness and ventilatory efficiency compared with the 2 other groups (group 1: ▵ = -2.5±0.5 units; group 2: ▵ = -0.8±0.3 units; and group 3: ▵ = -1.4±0.6 units, respectively; p<0.05. CONCLUSIONS: Coronary artery disease patients with lower aerobic fitness status exhibited lower ventilatory efficiency during a graded exercise test. In addition, after 3 months of aerobic exercise training, only the patients with initially lower levels of aerobic fitness exhibited greater improvements in ventilatory efficiency.

  13. Resistance training and aerobic training improve muscle strength and aerobic capacity in chronic inflammatory demyelinating polyneuropathy

    DEFF Research Database (Denmark)

    Markvardsen, Lars H; Overgaard, Kristian; Heje, Karen

    2018-01-01

    after a run-in period of 12 weeks without exercise. Three times weekly the participants performed aerobic exercise on an ergometer bike or resistance exercise with unilateral training of knee and elbow flexion/extension. Primary outcomes were maximal oxygen consumption velocity (VO2 -max) and maximal...

  14. Time series analysis of aerobic bacterial flora during Miso fermentation.

    Science.gov (United States)

    Onda, T; Yanagida, F; Tsuji, M; Shinohara, T; Yokotsuka, K

    2003-01-01

    This article reports a microbiological study of aerobic mesophilic bacteria that are present during the fermentation process of Miso. Aerobic bacteria were enumerated and isolated from Miso during fermentation and divided into nine groups using traditional phenotypic tests. The strains were identified by biochemical analysis and 16S rRNA sequence analysis. They were identified as Bacillus subtilis, B. amyloliquefaciens, Kocuria kristinae, Staphylococcus gallinarum and S. kloosii. All strains were sensitive to the bacteriocins produced by the lactic acid bacteria isolated from Miso. The dominant species among the undesirable species throughout the fermentation process were B. subtilis and B. amyloliquefaciens. It is suggested that bacteriocin-producing lactic acid bacteria are effective in the growth prevention of aerobic bacteria in Miso. This study has provided useful information for controlling of bacterial flora during Miso fermentation.

  15. Does aerobic exercise improve or impair cardiorespiratory fitness and health among cleaners?

    DEFF Research Database (Denmark)

    Korshøj Larsen, Mette; Lidegaard, Mark; Skotte, Jørgen H

    2015-01-01

    OBJECTIVE: It is unknown if aerobic exercise overloads or improves the cardiovascular system among workers with high occupational physical activity. This was investigated in a worksite randomized controlled trial (RCT) of aerobic exercise among cleaners. METHODS: We randomized 116 cleaners betwee...

  16. [Formation Mechanism of Aerobic Granular Sludge and Removal Efficiencies in Integrated ABR-CSTR Reactor].

    Science.gov (United States)

    Wu, Kai-cheng; Wu, Peng; Xu, Yue-zhong; Li, Yue-han; Shen, Yao-liang

    2015-08-01

    Anaerobic Baffled Reactor (ABR) was altered to make an integrated anaerobic-aerobic reactor. The research investigated the mechanism of aerobic sludge granulation, under the condition of continuous-flow. The last two compartments of the ABR were altered into aeration tank and sedimentation tank respectively with seeded sludge of anaerobic granular sludge in anaerobic zone and conventional activated sludge in aerobic zone. The HRT was gradually decreased in sedimentation tank from 2.0 h to 0.75 h and organic loading rate was increased from 1.5 kg x (M3 x d)(-1) to 2.0 kg x (M3 x d)(-1) while the C/N of 2 was controlled in aerobic zone. When the system operated for 110 days, the mature granular sludge in aerobic zone were characterized by compact structure, excellent sedimentation performance (average sedimentation rate was 20.8 m x h(-1)) and slight yellow color. The system performed well in nitrogen and phosphorus removal under the conditions of setting time of 0.75 h and organic loading rate of 2.0 kg (m3 x d)(-1) in aerobic zone, the removal efficiencies of COD, NH4+ -N, TP and TN were 90%, 80%, 65% and 45%, respectively. The results showed that the increasing selection pressure and the high organic loading rate were the main propulsions of the aerobic sludge granulation.

  17. Coupling model of aerobic waste degradation considering temperature, initial moisture content and air injection volume.

    Science.gov (United States)

    Ma, Jun; Liu, Lei; Ge, Sai; Xue, Qiang; Li, Jiangshan; Wan, Yong; Hui, Xinminnan

    2018-03-01

    A quantitative description of aerobic waste degradation is important in evaluating landfill waste stability and economic management. This research aimed to develop a coupling model to predict the degree of aerobic waste degradation. On the basis of the first-order kinetic equation and the law of conservation of mass, we first developed the coupling model of aerobic waste degradation that considered temperature, initial moisture content and air injection volume to simulate and predict the chemical oxygen demand in the leachate. Three different laboratory experiments on aerobic waste degradation were simulated to test the model applicability. Parameter sensitivity analyses were conducted to evaluate the reliability of parameters. The coupling model can simulate aerobic waste degradation, and the obtained simulation agreed with the corresponding results of the experiment. Comparison of the experiment and simulation demonstrated that the coupling model is a new approach to predict aerobic waste degradation and can be considered as the basis for selecting the economic air injection volume and appropriate management in the future.

  18. EFEKTIVITAS SISTEM BIOFILTER AEROB DALAM MENURUNKAN KADAR AMONIA PADA AIR LIMBAH

    Directory of Open Access Journals (Sweden)

    Ni Made Indra Wahyuni

    2015-06-01

    Full Text Available The increasingpopulationand activity of the Balinese people can increase the amount of waste as a byproduct of community activities. The presence of the metabolites in wastewater as ammonia is toxic to aquatic organisms. Application aerobic biofilter system can be used as an attempt to reduce levels of ammonia. In the aerobic biofilter, contact between the gravel media with microorganisms that form biofilmsare able to accelerate the degradation of organic matter and nitrification processes. The aims of this research are to determine the best consortium of activated sludge to reduce ammonia levels by aerobic biofilter system and to determine the effectivity of aerobic biofilter system. The first stage of this research were seeding of activated sludge from three sources are Wastewater Treatment Plan (WWTP of Suwung Denpasar, WWTP of Wangaya Hospital and WWTP of Bali Tourism Development Corporation (BTDC Nusa Dua Bali, for six days. This research was done by measuring Volatile Suspended Solid (VSS value that showed the growth rate of biomass in activated sludge. The second stage wereapplication of activated sludges and control in aerobic biofilter to reduce ammonia levels, for five days. This study used a Completely Randomized Design with four treatments and three repetitions. The results showed that the best activated sludge obtained from WWTP of Suwung Denpasar indicated by the highest biomass growth (VSS value of 2396.6 mg/L and was able to reduce ammonia up to 0.78 mg/ L. The effectivity of aerobic biofilter system with activated sludge from WWTP of Suwung Denpasar achieve effectivity of treatment process up to 92.20 % and have been able to pass the effectivity of quality standards (90% during five days of processing. The effectivity levels was the highest compared to control and activated sludgetreatments.

  19. Steps Counts among Middle School Students Vary with Aerobic Fitness Level

    Science.gov (United States)

    Le Masurier, Guy C.; Corbin, Charles B.

    2006-01-01

    The purpose of this study was to examine if steps/day taken by middle school students varied based on aerobic fitness classification. Middle school students (N = 223; 112 girls, 111 boys) were assigned to three aerobic fitness categories (HIGH, MOD, LOW) based on results of the FITNESSGRAM PACER test. Four weekdays of pedometer monitoring…

  20. Detoxification of furfural in Corynebacterium glutamicum under aerobic and anaerobic conditions.

    Science.gov (United States)

    Tsuge, Yota; Hori, Yoshimi; Kudou, Motonori; Ishii, Jun; Hasunuma, Tomohisa; Kondo, Akihiko

    2014-10-01

    The toxic fermentation inhibitors in lignocellulosic hydrolysates raise serious problems for the microbial production of fuels and chemicals. Furfural is considered to be one of the most toxic compounds among these inhibitors. Here, we describe the detoxification of furfural in Corynebacterium glutamicum ATCC13032 under both aerobic and anaerobic conditions. Under aerobic culture conditions, furfuryl alcohol and 2-furoic acid were produced as detoxification products of furfural. The ratio of the products varied depending on the initial furfural concentration. Neither furfuryl alcohol nor 2-furoic acid showed any toxic effect on cell growth, and both compounds were determined to be the end products of furfural degradation. Interestingly, unlike under aerobic conditions, most of the furfural was converted to furfuryl alcohol under anaerobic conditions, without affecting the glucose consumption rate. Both the NADH/NAD(+) and NADPH/NADP(+) ratio decreased in the accordance with furfural concentration under both aerobic and anaerobic conditions. These results indicate the presence of a single or multiple endogenous enzymes with broad and high affinity for furfural and co-factors in C. glutamicum ATCC13032.

  1. Deep shaft high rate aerobic digestion: laboratory and pilot plant performance

    Energy Technology Data Exchange (ETDEWEB)

    Tran, F; Gannon, D

    1981-01-01

    The Deep Shaft is essentially an air-lift reactor, sunk deep in the ground (100-160 m); the resulting high hydrostatic pressure together with very efficient mixing in the shaft provide extremely high O transfer efficiencies (O.T.E.) of less than or equal to 90% vs. 4-20% in other aerators. This high O.T.E. suggests real potential for Deep-Shaft technology in the aerobic digestion of sludges and animal wastes: with conventional aerobic digesters an O.T.E. over 8% is extremely difficult to achieve. Laboratory and pilot plant Deep-Shaft aerobic digester studies carried out at Eco-Research's Pointe Claire, Quebec laboratories, and at the Paris, Ontario pilot Deep-Shaft digester are described.

  2. Sub-Symptomatic Aerobic Exercise for Patients with Post-Concussion Syndrome: A Critically Appraised Topic.

    Science.gov (United States)

    Ritter, Katrina G; Hussey, Matthew J; Valovich McLeod, Tamara C

    2017-09-27

    Clinical Scenario: Patients who experience prolonged concussion symptoms can be diagnosed with Post-Concussion Syndrome (PCS) when those symptoms persist past 4 weeks. Aerobic exercise protocols have been shown to be effective in improving physical and mental aspects of health. Emerging research suggests that aerobic exercise maybe useful as a treatment for PCS, where exercise allows patients to feel less isolated and more active during the recovery process. Is aerobic exercise more beneficial in reducing symptoms than current standard care in patients with prolonged symptoms or PCS lasting longer than 4 weeks? Summary of Key Findings: After a thorough literature search, 4 studies were selected relevant to the clinical question. Of the 4 studies, 1 was a randomized control trial and 3 were case series. All 4 studies investigate aerobic exercise protocol as treatment for PCS. 1-4 Three articles demonstrated a greater rate of symptom improvement from baseline assessment to follow-up after a controlled sub-symptomatic aerobic exercise program. 2-4 One study showed a decrease in symptoms in the aerobic exercise group compared to the full body stretching group. 1 Clinical Bottom Line: There is moderate evidence to support sub-symptomatic aerobic exercise as a treatment of PCS, therefore it should be considered as a clinical option for reducing PCS and prolonged concussion symptoms. A previously validated protocol, such as the Buffalo Concussion Treadmill Test, Balke Protocol, or Rating of Perceived Exertion (RPE) as mentioned in this critically appraised topic should be used to measure baseline values and treatment progression. Strength of Recommendation: Level C evidence exists that aerobic exercise protocol is more effective than the current standard of care in treating PCS.

  3. Ginger extract and aerobic training reduces lipid profile in high-fat fed diet rats.

    Science.gov (United States)

    Khosravani, M; Azarbayjani, M A; Abolmaesoomi, M; Yusof, A; Zainal Abidin, N; Rahimi, E; Feizolahi, F; Akbari, M; Seyedjalali, S; Dehghan, F

    2016-04-01

    Obesity, hyperglycemia and dyslipidemia, are major risk factors. However, natural therapies, dietary components, and physical activity may effect on these concerns. The aim of this study was to examine the effect of aerobic exercise and consumption of liquid ginger extract on lipid profile of Male rats with a high-fat fed diet. 32 rats were randomly divided into 4 groups: 1) aerobic exercise, 2) Ginger extract, 3) combined aerobic exercise and Ginger extract, and 4) the control. Subjects of the first three groups received ginger extract via gavage feeding of 250 mg/kg. The exercise program was 3 sessions per week on 3 different days over 4 weeks. Total cholesterol (TC), Triglyceride (TG), HDL and LDL were measured 24-h before the first session and 24-h after the final training session. The concentration of TG in the control group was significantly higher than other groups. In addition, the mean concentration of TG in the aerobic exercise group was significantly lower than Ginger extract group but there was no significant difference as compared to combined aerobic exercise and ginger extract group. The combination of aerobic exercise and ginger consumption significantly reduced the TG level compared to ginger group. TC and LDL concentrations were significantly decreased in all groups compare to control. The combination of aerobic exercise and ginger extract feeding caused a significant increase in HDL levels. The finding of this study suggests that the combination of aerobic exercise and liquid ginger extract consumption might be an effective method of reducing lipid profiles, which will reduce the risk of cardiovascular diseases caused by high-fat diets.

  4. Comparison of yoga and aerobic trainings for improving mental health of divorced women

    Directory of Open Access Journals (Sweden)

    Afrooz Mousavi

    2017-11-01

    Full Text Available Exercise is an acceptable method for improving and maintaining the physical and emotional health. The aim of the present study was to compare the effectiveness of yoga training program and aerobic exercise on the mental health of divorced women. Two experimental groups and one control group were employed in this quasi-experimental study. The number of 30 divorced women was randomly divided into three groups. The experimental groups involved in yoga (n=10 and aerobics training (n=10 and received 16 exercise sessions for two months. The control group (n=10 received no training. General health questionnaire-28 was employed to evaluate the mental health of participants. Covariance analysis was used as the statistical method. The obtained results indicated that the intervention improved significantly the mental health indices in the intervention groups of yoga and aerobics. In comparison of the effectiveness of yoga and aerobics exercises, the results showed that there is not significant difference between the effectiveness of yoga and aerobics. Therefore, the two methods of exercise are effective on improving the mental health

  5. PENGOLAHAN LIMBAH CAIR INDUSTRI FARMASI FORMULASI DENGAN METODE ANAEROB-AEROB DAN ANAEROB-KOAGULASI

    Directory of Open Access Journals (Sweden)

    Farida Crisnaningtyas

    2016-05-01

    Full Text Available Studi ini membahas mengenai pengolahan limbah cair industri farmasi dalam skala laboratorium dengan menggunakan konsep anaerob-kimia-fisika dan anaerob-aerob. Proses anaerob dilakukan dengan menggunakan reaktor Upflow Anaerobic Sludge Bed reactor (UASBr pada kisaran OLR (Organic Loading Rate 0,5 – 2 kg COD/m3hari, yang didahului dengan proses aklimatisasi menggunakan substrat gula. Proses anaerob mampu memberikan efisiensi penurunan COD hingga 74%. Keluaran dari proses anaerob diolah lebih lanjut dengan menggunakan dua opsi proses: (1 fisika-kimia, dan (2 aerob. Koagulan alumunium sulfat dan flokulan kationik memberikan efisiensi penurunan COD tertinggi (73% pada kecepatan putaran masing-masing 100 rpm dan 40 rpm. Uji coba aerob dilakukan pada kisaran MLSS antara 4000-5000 mg/L dan mampu memberikan efisiensi penurunan COD hingga 97%. Hasil uji coba menunjukkan bahwa efisiensi penurunan COD total yang dapat dicapai dengan menggunakan teknologi anaerob-aerob adalah 97%, sedangkan kombinasi anaerob-koagulasi-flokulasi hanya mampu menurunkan COD total sebesar 72,53%. Berdasarkan hasil tersebut, kombinasi proses anaerob-aerob merupakan teknologi yang potensial untuk diaplikasikan dalam sistem pengolahan limbah cair industri farmasi. 

  6. Aerobic training for improved memory in patients with stress-related exhaustion: a randomized controlled trial.

    Science.gov (United States)

    Eskilsson, Therese; Slunga Järvholm, Lisbeth; Malmberg Gavelin, Hanna; Stigsdotter Neely, Anna; Boraxbekk, Carl-Johan

    2017-09-02

    Patients with stress-related exhaustion suffer from cognitive impairments, which often remain after psychological treatment or work place interventions. It is important to find effective treatments that can address this problem. Therefore, the aim of this study was to investigate the effects on cognitive performance and psychological variables of a 12-week aerobic training program performed at a moderate-vigorous intensity for patients with exhaustion disorder who participated in a multimodal rehabilitation program. In this open-label, parallel, randomized and controlled trial, 88 patients diagnosed with exhaustion disorder participated in a 24-week multimodal rehabilitation program. After 12 weeks in the program the patients were randomized to either a 12-week aerobic training intervention or to a control group with no additional training. Primary outcome measure was cognitive function, and secondary outcome measures were psychological health variables and aerobic capacity. In total, 51% patients in the aerobic training group and 78% patients in the control group completed the intervention period. The aerobic training group significantly improved in maximal oxygen uptake and episodic memory performance. No additional improvement in burnout, depression or anxiety was observed in the aerobic group compared with controls. Aerobic training at a moderate-vigorous intensity within a multimodal rehabilitation program for patients with exhaustion disorder facilitated episodic memory. A future challenge would be the clinical implementation of aerobic training and methods to increase feasibility in this patient group. ClinicalTrials.gov: NCT03073772 . Retrospectively registered 21 February 2017.

  7. Processing biodegradable waste by applying aerobic digester EWA

    Directory of Open Access Journals (Sweden)

    Đokić Dragoslav

    2014-01-01

    Full Text Available The paper presents research results obtained in the process of processing biodegradable wastes, resulting from agricultural production as well as municipal waste. Aerobic fermenter EWA (stationed within the Institute for Forage Crops Globoder- Kruševac was using for this purpose, during the one month testing. Biodegradable material with different ratios of components was used for filling aerobic digester. EWA fermenter is certified device that is used to stabilize and hygienic disposal of biodegradable waste, including sewage sludge and animal products produced in accordance with European Union regulations. Fermenter is intended to be used for combustion in boilers for solid fuels with humidity of biomaterials below 30%.

  8. Aerobic landfill bioreactor

    Science.gov (United States)

    Hudgins, Mark P; Bessette, Bernard J; March, John C; McComb, Scott T.

    2002-01-01

    The present invention includes a system of decomposing municipal solid waste (MSW) within a landfill by converting the landfill to aerobic degradation in the following manner: (1) injecting air via the landfill leachate collection system (2) injecting air via vertical air injection wells installed within the waste mass; (3) applying leachate to the waste mass using a pressurized drip irrigation system; (4) allowing landfill gases to vent; and (5) adjusting air injection and recirculated leachate to achieve a 40% to 60% moisture level and a temperature between 120.degree. F. and 140.degree. F. in steady state.

  9. Aerobic and anaerobic bacteria in tonsils of children with recurrent tonsillitis.

    Science.gov (United States)

    Brook, I; Yocum, P; Friedman, E M

    1981-01-01

    Tonsils were obtained from 50 children suffering from recurrent tonsillitis. Patients' ages ranged from 2.5 to 17 years (mean 6 years); 29 were males and 21 females. The tonsils were sectioned in half after heat searing of the surface and the core material was cultured for aerobic and anaerobic microorganisms. Mixed aerobic and anaerobic flora was obtained in all patients, yielding an average of 7.8 isolates (4.1 anaerobes and 3.7 aerobes) per specimen. There were 207 anaerobes isolated. The predominant isolates were 101 Bacteroides sp (including 10 B fragilis group, and 47 B melaninogenicus group), 29 Fusobacterium sp, 34 Gram-positive anaerobic cocci (25 Peptococcus sp and 9 Peptostreptococcus sp) and 16 Veillonella sp. There were 185 aerobic isolates. The predominant isolates were 41 alpha-hemolytic streptococci, 24 Staphylococcus aureus, 19 beta-hemolytic streptococci (11 group A, 4 group B, and 2 each group C and F), 14 Haemophilus sp (including 12 H influenzae type B) and 5 H parainfluenzae. Beta-lactamase production was noted in 56 isolates recovered from 37 tonsils. These were all isolates of S aureus (24) and B fragilis (10), 15 of 47 B melaninogenicus (32%), 5 of the 12 B oralis (42%), and 2 of 12 H influenzae type B (17%). Our findings indicate the polymicrobial aerobic and anaerobic nature of deep tonsillar flora in children with recurrent tonsillitis, and demonstrate the presence of many beta-lactamase-producing organisms in 74% of the patients.

  10. Triad of physical activity, aerobic fitness and obesity in adolescents and young adults with myelomeningocele.

    Science.gov (United States)

    Buffart, Laurien M; Roebroeck, Marij E; Rol, Mathilde; Stam, Henk J; van den Berg-Emons, Rita J G

    2008-01-01

    Comprehensively and objectively assess physical activity, aerobic fitness and body fat in adolescents and young adults with myelomeningocele and to investigate their relationships. Cross-sectional study. Fifty-one persons (26 males) with myelomeningocele aged 21.1 (standard deviation) 4.5) years. Physical activity was measured with an accelerometry-based activity monitor. Aerobic fitness was defined as the maximum oxygen uptake during the last minute of a maximal exercise test. Body fat was assessed using sum of 4 skin-folds and body mass index. Correlations were studied using multiple regression analyses. Thirty-nine percent of the participants were inactive and another 37% were extremely inactive. Aerobic fitness was 42% lower than normative values and 35% were obese. Ambulatory status was related to daily physical activity (beta = 0.541), aerobic fitness (beta = 0.397) and body fat (beta = -0.243). Gender was related to aerobic fitness (beta = -0.529) and body fat (beta = 0.610). Physical activity was related to aerobic fitness in non-ambulatory persons with myelomeningocele (beta = 0.398), but not in ambulatory persons. Adolescents and young adults with myelomeningocele were physically inactive, had poor aerobic fitness and high body fat. Differences exist between subgroups regarding gender and ambulatory status.

  11. Influence of leachate recirculation on aerobic and anaerobic decomposition of solid wastes

    International Nuclear Information System (INIS)

    Bilgili, M. Sinan; Demir, Ahmet; Ozkaya, Bestamin

    2007-01-01

    In this study, the effect of leachate recirculation on aerobic and anaerobic degradation of municipal solid wastes is determined by four laboratory-scale landfill reactors. The options studied and compared with the traditional anaerobic landfill are: leachate recirculation, landfill aeration, and aeration with leachate recirculation. Leachate quality is regularly monitored by the means of pH, alkalinity, total dissolved solids, conductivity, oxidation-reduction potential, chloride, chemical oxygen demand, ammonia, and total Kjeldahl nitrogen, in addition to generated leachate quantity. Aerobic leachate recirculated landfill appears to be the most effective option in the removal of organic matter and ammonia. The main difference between aerobic recirculated and non-recirculated landfill options is determined at leachate quantity. Recirculation is more effective on anaerobic degradation of solid waste than aerobic degradation. Further studies are going on to determine the optimum operational conditions for aeration and leachate recirculation rates, also with the operational costs of aeration and recirculation

  12. Complete genome sequence of the aerobically denitrifying thermophilic bacterium Chelatococcus daeguensis TAD1

    Directory of Open Access Journals (Sweden)

    Yunlong Yang

    Full Text Available ABSTRACT Chelatococcus daeguensis TAD1 is a themophilic bacterium isolated from a biotrickling filter used to treat NOx in Ruiming Power Plant, located in Guangzhou, China, which shows an excellent aerobic denitrification activity at high temperature. The complete genome sequence of this strain was reported in the present study. Genes related to the aerobic denitrification were identified through whole genome analysis. This work will facilitate the mechanism of aerobic denitrification and provide evidence for its potential application in the nitrogen removal.

  13. Root morphology, hydraulic conductivity and plant water relations of high-yielding rice grown under aerobic conditions.

    Science.gov (United States)

    Kato, Yoichiro; Okami, Midori

    2011-09-01

    Increasing physical water scarcity is a major constraint for irrigated rice (Oryza sativa) production. 'Aerobic rice culture' aims to maximize yield per unit water input by growing plants in aerobic soil without flooding or puddling. The objective was to determine (a) the effect of water management on root morphology and hydraulic conductance, and (b) their roles in plant-water relationships and stomatal conductance in aerobic culture. Root system development, stomatal conductance (g(s)) and leaf water potential (Ψ(leaf)) were monitored in a high-yielding rice cultivar ('Takanari') under flooded and aerobic conditions at two soil moisture levels [nearly saturated (> -10 kPa) and mildly dry (> -30 kPa)] over 2 years. In an ancillary pot experiment, whole-plant hydraulic conductivity (soil-leaf hydraulic conductance; K(pa)) was measured under flooded and aerobic conditions. Adventitious root emergence and lateral root proliferation were restricted even under nearly saturated conditions, resulting in a 72-85 % reduction in total root length under aerobic culture conditions. Because of their reduced rooting size, plants grown under aerobic conditions tended to have lower K(pa) than plants grown under flooded conditions. Ψ(leaf) was always significantly lower in aerobic culture than in flooded culture, while g(s) was unchanged when the soil moisture was at around field capacity. g(s) was inevitably reduced when the soil water potential at 20-cm depth reached -20 kPa. Unstable performance of rice in water-saving cultivations is often associated with reduction in Ψ(leaf). Ψ(leaf) may reduce even if K(pa) is not significantly changed, but the lower Ψ(leaf) would certainly occur in case K(pa) reduces as a result of lower water-uptake capacity under aerobic conditions. Rice performance in aerobic culture might be improved through genetic manipulation that promotes lateral root branching and rhizogenesis as well as deep rooting.

  14. Strength and Aerobic Exercises Improve Spatial Memory in Aging Rats Through Stimulating Distinct Neuroplasticity Mechanisms.

    Science.gov (United States)

    Vilela, Thais Ceresér; Muller, Alexandre Pastoris; Damiani, Adriani Paganini; Macan, Tamires Pavei; da Silva, Sabrina; Canteiro, Paula Bortoluzzi; de Sena Casagrande, Alisson; Pedroso, Giulia Dos Santos; Nesi, Renata Tiscoski; de Andrade, Vanessa Moraes; de Pinho, Ricardo Aurino

    2017-12-01

    Aging is associated with impaired cognition and memory and increased susceptibility to neurodegenerative disorders. Physical exercise is neuroprotective; however, the major evidence of this effect involves studies of only aerobic training in young animals. The benefits of other exercise protocols such as strength training in aged animals remains unknown. Here, we investigated the effect of aerobic and strength training on spatial memory and hippocampal plasticity in aging rats. Aging Wistar rats performed aerobic or strength training for 50 min 3 to 4 days/week for 8 weeks. Spatial memory and neurotrophic and glutamatergic signaling in the hippocampus of aged rats were evaluated after aerobic or strength training. Both aerobic and strength training improved cognition during the performance of a spatial memory task. Remarkably, the improvement in spatial memory was accompanied by an increase in synaptic plasticity proteins within the hippocampus after exercise training, with some differences in the intracellular functions of those proteins between the two exercise protocols. Moreover, neurotrophic signaling (CREB, BDNF, and the P75 NTR receptor) increased after training for both exercise protocols, and aerobic exercise specifically increased glutamatergic proteins (NMDA receptor and PSD-95). We also observed a decrease in DNA damage after aerobic training. In contrast, strength training increased levels of PKCα and the proinflammatory factors TNF-α and IL-1β. Overall, our results show that both aerobic and strength training improved spatial memory in aging rats through inducing distinct molecular mechanisms of neuroplasticity. Our findings extend the idea that exercise protocols can be used to improve cognition during aging.

  15. Adherence to an Aerobic Exercise Intervention after an Implantable Cardioverter Defibrillator (ICD).

    Science.gov (United States)

    Dougherty, Cynthia M; Luttrell, Matilda N; Burr, Robert L; Kim, Misun; Haskell, William L

    2016-02-01

    Exercise adherence is an important element in achieving important exercise outcomes. The purpose of this study was to describe adherence in a home-based aerobic exercise program following an implantable cardioverter defibrillator (ICD), determine effects of adherence on peakVO2 , and outline reasons for nonadherence. A single-blind randomized control trial of home walking compared to usual care in 160 patients with an ICD for primary or secondary prevention was conducted. This report is on adherence in the exercise arm (N = 84). Home walking exercise consisted of 8 weeks of aerobic conditioning (60 minutes/day, 5 days/week) followed by 16 weeks of aerobic maintenance (150 minutes/week, 30 minutes/session) at 60-80% of heart rate reserve. Adherence was tracked using Polar heart rate (HR) monitors, pedometers, home exercise logs, and telephone follow-up. Adherence was defined as performing at least 80% of prescribed exercise. For aerobic conditioning, there was a mean frequency of 3.81 walks/week, duration of 1,873 minutes walked, and 17.5% of exercise was in the target HR (THR) zone. For aerobic maintenance, there was a mean frequency of 2.4 walks/week, duration of 1,872 minutes/walked, and 8.7% of exercise was in the THR zone. Those who were 80% adherent achieved a 3.4 mL/kg/min (P = 0.03) improvement in peakVO2 over those who were exercise ranged from scheduling issues to viral illness and fatigue. Adherence to aerobic exercise frequency and duration was high with few dropouts, resulting in higher peakVO2 . Exercise monitoring equipment encouraged adherence and conferred a sense of safety to exercise. ©2015 Wiley Periodicals, Inc.

  16. Effect of aerobic capacity on Lower Body Negative Pressure (LBNP) tolerance in females

    Science.gov (United States)

    Moore, Alan D., Jr.; Fortney, Suzanne M.; Siconolfi, Steven F.

    1993-01-01

    This investigation determined whether a relationship exists in females between: (1) aerobic capacity and Lower Body Negative Pressure (LBNP); and (2) aerobic capacity and change in LBNP tolerance induced by bed rest. Nine females, age 27-47 (34.6 plus or minus 6.0 (Mean plus or minus SD)), completed a treadmill-graded exercise test to establish aerobic capacity. A presyncopal-limited LBNP test was performed prior to and after 13 days of bed rest at a 6 deg head-down tilt. LBNP tolerance was quantified as: (1) the absolute level of negative pressure (NP) tolerated for greater than or equal to 60 sec; and (2) Luft's Cumulative Stress Index (CSI). Aerobic capacity was 33.3 plus or minus 5.0 mL/kg/min and ranged from 25.7 to 38.7. Bed rest was associated with a decrease in NP tolerance (-9.04 1.6 kPa(-67.8 plus or minus 12.0 mmHg) versus -7.7 1.1 kPa(-57.8 plus or minus 8.33 mmHg); p = 0.028) and in CSI (99.4 27.4 kPa min(745.7 plus or minus 205.4 mmHg min) versus 77.0 16.9 kPa min (577.3 plus or minus mmHg min); p = 0.008). The correlation between aerobic capacity and absolute NP or CSI pre-bed rest did not differ significantly from zero (r = -0.56, p = 0.11 for NP; and r = -0.52, p = 0.16 for CSI). Also, no significant correlation was observed between aerobic and pre- to post-rest change for absolute NP tolerance (r = -0.35, p = 0.35) or CSI (r = -0.32, p = 0.40). Therefore, a significant relationship does not exist between aerobic capacity and orthostatic function or change in orthostatic function induced by bed rest.

  17. Isolation and identification of aerobic polychlorinated biphenyls degrading bacteria

    Directory of Open Access Journals (Sweden)

    Bibi Fatemeh Nabavi

    2013-01-01

    Full Text Available Aims: The purpose of this study was to isolate and identify aerobic polychlorinated biphenyls (PCBs degrading bacteria. Materials and Methods: This study was performed in lab scale aerobic sequencing batch biofilm reactor. Polyurethane foams were used as bio-carrier and synthetic wastewater was prepared with PCBs in transformer oil as the main substrate (20-700 μg/l and acetone as a solvent for PCBs as well as microelements. After achieving to adequate microbial population and acclimation of microorganisms to PCB compounds with high efficiency of PCB removal, identification of degrading microbial species was performed by 16s rRNA gene sequencing of isolated bacteria. Results: Gene sequencing results of the isolated bacteria showed that Rhodococcus spp., Pseudomonas spp., Pseudoxanthomonas spp., Agromyces spp., and Brevibacillus spp. were dominant PCB-degrading bacteria. Conclusion: PCB compounds can be degraded by some microorganisms under aerobic or anaerobic conditions or at least be reduced to low chlorinated congeners, despite their chemical stability and toxicity. Based on the results of the study, five bacterial species capable of degrading PCBs in transformer oil have been identified.

  18. Interaction of polybrominated diphenyl ethers and aerobic granular sludge: biosorption and microbial degradation.

    Science.gov (United States)

    Ni, Shou-Qing; Cui, Qingjie; Zheng, Zhen

    2014-01-01

    As a new category of persistent organic pollutants, polybrominated diphenyl ethers (PBDEs) have become ubiquitous global environmental contaminants. No literature is available on the aerobic biotransformation of decabromodiphenyl ether (BDE-209). Herein, we investigated the interaction of PBDEs with aerobic granular sludge. The results show that the removal of BDE-209 from wastewater is mainly via biosorption onto aerobic granular sludge. The uptake capacity increased when temperature, contact time, and sludge dosage increased or solution pH dropped. Ionic strength had a negative influence on BDE-209 adsorption. The modified pseudo first-order kinetic model was appropriate to describe the adsorption kinetics. Microbial debromination of BDE-209 did not occur during the first 30 days of operation. Further study found that aerobic microbial degradation of 4,4(')-dibromodiphenyl ether happened with the production of lower BDE congeners.

  19. Interaction of Polybrominated Diphenyl Ethers and Aerobic Granular Sludge: Biosorption and Microbial Degradation

    Directory of Open Access Journals (Sweden)

    Shou-Qing Ni

    2014-01-01

    Full Text Available As a new category of persistent organic pollutants, polybrominated diphenyl ethers (PBDEs have become ubiquitous global environmental contaminants. No literature is available on the aerobic biotransformation of decabromodiphenyl ether (BDE-209. Herein, we investigated the interaction of PBDEs with aerobic granular sludge. The results show that the removal of BDE-209 from wastewater is mainly via biosorption onto aerobic granular sludge. The uptake capacity increased when temperature, contact time, and sludge dosage increased or solution pH dropped. Ionic strength had a negative influence on BDE-209 adsorption. The modified pseudo first-order kinetic model was appropriate to describe the adsorption kinetics. Microbial debromination of BDE-209 did not occur during the first 30 days of operation. Further study found that aerobic microbial degradation of 4,4′-dibromodiphenyl ether happened with the production of lower BDE congeners.

  20. Aerobic Glycolysis Is Essential for Normal Rod Function and Controls Secondary Cone Death in Retinitis Pigmentosa.

    Science.gov (United States)

    Petit, Lolita; Ma, Shan; Cipi, Joris; Cheng, Shun-Yun; Zieger, Marina; Hay, Nissim; Punzo, Claudio

    2018-05-29

    Aerobic glycolysis accounts for ∼80%-90% of glucose used by adult photoreceptors (PRs); yet, the importance of aerobic glycolysis for PR function or survival remains unclear. Here, we further established the role of aerobic glycolysis in murine rod and cone PRs. We show that loss of hexokinase-2 (HK2), a key aerobic glycolysis enzyme, does not affect PR survival or structure but is required for normal rod function. Rods with HK2 loss increase their mitochondrial number, suggesting an adaptation to the inhibition of aerobic glycolysis. In contrast, cones adapt without increased mitochondrial number but require HK2 to adapt to metabolic stress conditions such as those encountered in retinitis pigmentosa, where the loss of rods causes a nutrient shortage in cones. The data support a model where aerobic glycolysis in PRs is not a necessity but rather a metabolic choice that maximizes PR function and adaptability to nutrient stress conditions. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  1. Effect of Aerobic Exercise Training on Blood Pressure in Indians: Systematic Review

    Directory of Open Access Journals (Sweden)

    Sonu Punia

    2016-01-01

    Full Text Available Introduction. High blood pressure (BP is one of the most important modifiable risk factors for cardiovascular diseases, which accounts for one in every eight deaths worldwide. It has been predicted that, by 2020, there would be 111% increase in cardiovascular deaths in India. Aerobic exercise in the form of brisk walking, jogging, running, and cycling would result in reduction in BP. Many meta-analytical studies from western world confirm this. However, there is no such review from Indian subcontinent. Objective. Our objective is to systematically review and report the articles from India in aerobic exercise on blood pressure. Methodology. Study was done in March 2016 in Google Scholar using search terms “Aerobic exercise” AND “Training” AND “Blood pressure” AND “India.” This search produced 3210 titles. Results. 24 articles were identified for this review based on inclusion and exclusion criteria. Total of 1107 subjects participated with median of 25 subjects. Studies vary in duration from +3 weeks to 12 months with each session lasting 15–60 minutes and frequency varies from 3 to 8 times/week. The results suggest that there was mean reduction of −05.00 mmHg in SBP and −03.09 mmHg in DBP after aerobic training. Conclusion. Aerobic training reduces the blood pressure in Indians.

  2. Aerobic Exercise Training Improves Orthostatic Tolerance in Aging Humans.

    Science.gov (United States)

    Xu, Diqun; Wang, Hong; Chen, Shande; Ross, Sarah; Liu, Howe; Olivencia-Yurvati, Albert; Raven, Peter B; Shi, Xiangrong

    2017-04-01

    This study was designed to test the hypothesis that aerobic exercise training of the elderly will increase aerobic fitness without compromising orthostatic tolerance (OT). Eight healthy sedentary volunteers (67.0 ± 1.7 yr old, four women) participated in 1 yr of endurance exercise training (stationary bicycle and/or treadmill) program at the individuals' 65%-75% of HRpeak. Peak O2 uptake (V˙O2peak) and HRpeak were determined by a maximal exercise stress test using a bicycle ergometer. Carotid baroreceptor reflex (CBR) control of HR and mean arterial pressure (MAP) were assessed by a neck pressure-neck suction protocol. Each subject's maximal gain (Gmax), or sensitivity, of the CBR function curves were derived from fitting their reflex HR and MAP responses to the corresponding neck pressure-neck suction stimuli using a logistic function curve. The subjects' OT was assessed using lower-body negative pressure (LBNP) graded to -50 mm Hg; the sum of the product of LBNP intensity and time (mm Hg·min) was calculated as the cumulative stress index. Training increased V˙O2peak (before vs after: 22.8 ± 0.92 vs 27.9 ± 1.33 mL·min·kg, P stress index was increased from 767 ± 68 mm Hg·min pretraining to 946 ± 44 mm Hg·min posttraining (P Aerobic exercise training improved the aerobic fitness and OT in elderly subjects. An improved OT is likely associated with an enhanced CBR function that has been reset to better maintain cerebral perfusion and cerebral tissue oxygenation during LBNP.

  3. Top 10 Research Questions Related to Youth Aerobic Fitness.

    Science.gov (United States)

    Armstrong, Neil

    2017-06-01

    Peak oxygen uptake ([Formula: see text] 2 ) is internationally recognized as the criterion measure of youth aerobic fitness, but despite pediatric data being available for almost 80 years, its measurement and interpretation in relation to growth, maturation, and health remain controversial. The trainability of youth aerobic fitness continues to be hotly debated, and causal mechanisms of training-induced changes and their modulation by chronological age, biological maturation, and sex are still to be resolved. The daily physical activity of youth is characterized by intermittent bouts and rapid changes in intensity, but physical activity of the intensity and duration required to determine peak [Formula: see text] 2 is rarely (if ever) experienced by most youth. In this context, it may therefore be the transient kinetics of pulmonary [Formula: see text] 2 that best reflect youth aerobic fitness. There are remarkably few rigorous studies of youth pulmonary [Formula: see text] 2 kinetics at the onset of exercise in different intensity domains, and the influence of chronological age, biological maturation, and sex during step changes in exercise intensity are not confidently documented. Understanding the trainability of the parameters of youth pulmonary [Formula: see text] 2 kinetics is primarily based on a few comparative studies of athletes and nonathletes. The underlying mechanisms of changes due to training require further exploration. The aims of the present article are therefore to provide a brief overview of aerobic fitness during growth and maturation, increase awareness of current controversies in its assessment and interpretation, identify gaps in knowledge, raise 10 relevant research questions, and indicate potential areas for future research.

  4. Aquatic-Aerobic Exercise as a Means of Stress Reduction during Pregnancy

    OpenAIRE

    Parker, Kara Mallory; Smith, Sheila A.

    2003-01-01

    The goals of this research were to explore the current literature regarding associations between psychological stress and adverse fetal outcome, associations between aerobic exercise and psychological stress reduction, and associations between aerobic exercise and fetal outcome. The published studies that were located provide evidence of the following: 1) Stress reactivity increases physiologically during pregnancy, 2) pregnant women may experience additional stressors that are usually not ex...

  5. Inflammatory cytokines and immune system modulation by aerobic ...

    African Journals Online (AJOL)

    Keywords: Immune function, inflammatory cytokines, aerobic exercise, resistance exercise, aging. ... Physical exercise is effective in reducing (or ameliorate) the ..... moderate resistance training program increases muscle .... Nutrition Metabo-.

  6. Predicting Species-Resolved Macronutrient Acquisition during Succession in a Model Phototrophic Biofilm Using an Integrated ‘Omics Approach

    Directory of Open Access Journals (Sweden)

    Stephen R. Lindemann

    2017-06-01

    Full Text Available The principles governing acquisition and interspecies exchange of nutrients in microbial communities and how those exchanges impact community productivity are poorly understood. Here, we examine energy and macronutrient acquisition in unicyanobacterial consortia for which species-resolved genome information exists for all members, allowing us to use multi-omic approaches to predict species’ abilities to acquire resources and examine expression of resource-acquisition genes during succession. Metabolic reconstruction indicated that a majority of heterotrophic community members lacked the genes required to directly acquire the inorganic nutrients provided in culture medium, suggesting high metabolic interdependency. The sole primary producer in consortium UCC-O, cyanobacterium Phormidium sp. OSCR, displayed declining expression of energy harvest, carbon fixation, and nitrate and sulfate reduction proteins but sharply increasing phosphate transporter expression over 28 days. Most heterotrophic members likewise exhibited signs of phosphorus starvation during succession. Though similar in their responses to phosphorus limitation, heterotrophs displayed species-specific expression of nitrogen acquisition genes. These results suggest niche partitioning around nitrogen sources may structure the community when organisms directly compete for limited phosphate. Such niche complementarity around nitrogen sources may increase community diversity and productivity in phosphate-limited phototrophic communities.

  7. Condition of esthetic component of motive activity in aerobic gymnastics

    Directory of Open Access Journals (Sweden)

    Valentina Todorova

    2017-02-01

    Full Text Available Purpose: to prove condition of esthetic component of motive activity of sportsmen in aerobic gymnastics at various stages of sports preparation. Material & Methods: analysis of video records, method of expert assessment, methods of mathematical statistics. Results: the level of criteria of esthetic component ("musicality", "dancing", "illustrative expressiveness", and "emotional expressiveness" with use of the offered rating scale is determined. Conclusions: indicators of motive activities of sportsmen for aerobic gymnastics are defined at various stages of sports preparation.

  8. Aerobic fitness in children and young adults with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Madsen, Astrid Hellerup; Green, Kent; Buchvald, Frederik

    2013-01-01

    BACKGROUND: Although aerobic fitness is regarded as an overall prognostic measure of morbidity and mortality, its evaluation in the chronic progressive sinopulmonary disease primary ciliary dyskinesia (PCD) has been infrequently and inconsistently reported. Here we assessed peak oxygen uptake (VO2...... multiple breath inert gas washout (N2 MBW) were assessed in a cross-sectional, single-occasion study of clinically stable children and young adults with PCD. We used a questionnaire including self-reported physical limitations in everyday life or in vigorous activities, and estimation of weekly hours...... patients. CONCLUSION: One-third of PCD patients exhibited substantially lower aerobic fitness than healthy subjects. Aerobic fitness correlated with FEV1, DLCO/VA and self-reported complaints of limitations in vigorous physical activity. These findings are most likely explained by PCD pulmonary disease...

  9. Combined short-arm centrifuge and aerobic exercise training improves cardiovascular function and physical working capacity in humans.

    Science.gov (United States)

    Yang, Chang-Bin; Zhang, Shu; Zhang, Yu; Wang, Bing; Yao, Yong-Jie; Wang, Yong-Chun; Wu, Yan-Hong; Liang, Wen-Bin; Sun, Xi-Qing

    2010-12-01

    Musculoskeletal and cardiovascular deconditioning occurring in long-term spaceflight gives rise to the needs to develop new strategies to counteract these adverse effects. Short-arm centrifuge combined with ergometer has been proposed as a strategy to counteract adverse effects of microgravity. This study sought to investigate whether the combination of short-arm centrifuge and aerobic exercise training have advantages over short-arm centrifuge or aerobic exercise training alone. One week training was conducted by 24 healthy men. They were randomly divided into 3 groups: (1) short-arm centrifuge training, (2) aerobic exercise training, 40 W, and (3) combined short-arm centrifuge and aerobic exercise training. Before and after training, the cardiac pump function represented by stroke volume, cardiac output, left ventricular ejection time, and total peripheral resistance was evaluated. Variability of heart rate and systolic blood pressure were determined by spectral analysis. Physical working capacity was surveyed by near maximal physical working capacity test. The 1-week combined short-arm centrifuge and aerobic exercise training remarkably ameliorated the cardiac pump function and enhanced vasomotor sympathetic nerve modulation and improved physical working capacity by 10.9% (Pcentrifuge nor the aerobic exercise group showed improvements in these functions. These results demonstrate that combined short-arm centrifuge and aerobic exercise training has advantages over short-arm centrifuge or aerobic exercise training alone in influencing several physiologically important cardiovascular functions in humans. The combination of short-arm centrifuge and aerobic exercise offers a promising countermeasure to microgravity.

  10. Definition of a type of abnormal vaginal flora that is distinct from bacterial vaginosis: aerobic vaginitis.

    Science.gov (United States)

    Donders, Gilbert G G; Vereecken, Annie; Bosmans, Eugene; Dekeersmaecker, Alfons; Salembier, Geert; Spitz, Bernard

    2002-01-01

    To define an entity of abnormal vaginal flora: aerobic vaginitis. Observational study. University Hospital Gasthuisberg, Leuven, Belgium. 631 women attending for routine prenatal care or attending vaginitis clinic. Samples were taken for fresh wet mount microscopy of vaginal fluid, vaginal cultures and measurement of lactate, succinate and cytokine levels in vaginal fluid. Smears deficient in lactobacilli and positive for clue cells were considered to indicate a diagnosis of bacterial vaginosis. Aerobic vaginitis was diagnosed if smears were deficient in lactobacilli, positive for cocci or coarse bacilli, positive for parabasal epithelial cells, and/or positive for vaginal leucocytes (plus their granular aspect). Genital complaints include red inflammation, yellow discharge, vaginal dyspareunia. Group B streptococci, escherichia coli, staphylococcus aureus and trichomonas vaginalis are frequently cultured. Vaginal lactate concentration is severely depressed in women with aerobic vaginitis, as in bacterial vaginosis, but vaginal succinate is not produced. Also in contrast to bacterial vaginosis, aerobic vaginitis produces a host immune response that leads to high production of interleukin-6, interleukin-1-beta and leukaemia inhibitory factor in the vaginal fluid. Aerobic vaginitis is associated with aerobic micro-organisms, mainly group B streptococci and E. coli. Its characteristics are different from those of bacterial vaginosis and elicit an important host response. The most severe form of aerobic vaginitis equals desquamative inflammatory vaginitis. In theory, aerobic vaginitis may be a better candidate than bacterial vaginosis as the cause of pregnancy complications, such as ascending chorioamnionitis, preterm rupture of the membranes and preterm delivery.

  11. Influence of Aerobic Training and Combinations of Interventions on Cognition and Neuroplasticity after Stroke

    Science.gov (United States)

    Constans, Annabelle; Pin-barre, Caroline; Temprado, Jean-Jacques; Decherchi, Patrick; Laurin, Jérôme

    2016-01-01

    Stroke often aggravated age-related cognitive impairments that strongly affect several aspects of quality of life. However, few studies are, to date, focused on rehabilitation strategies that could improve cognition. Among possible interventions, aerobic training is well known to enhance cardiovascular and motor functions but may also induce beneficial effects on cognitive functions. To assess the effectiveness of aerobic training on cognition, it seems necessary to know whether training promotes the neuroplasticity in brain areas involved in cognitive functions. In the present review, we first explore in both human and animal how aerobic training could improve cognition after stroke by highlighting the neuroplasticity mechanisms. Then, we address the potential effect of combinations between aerobic training with other interventions, including resistance exercises and pharmacological treatments. In addition, we postulate that classic recommendations for aerobic training need to be reconsidered to target both cognition and motor recovery because the current guidelines are only focused on cardiovascular and motor recovery. Finally, methodological limitations of training programs and cognitive function assessment are also developed in this review to clarify their effectiveness in stroke patients. PMID:27445801

  12. Differences in neighborhood social cohesion and aerobic physical activity by Latino subgroup

    Directory of Open Access Journals (Sweden)

    Rosenda Murillo

    2016-12-01

    Full Text Available Previous research has examined the role of neighborhood social cohesion in physical activity outcomes; however, less is known about this relationship across Latino subgroups. The purpose of our study was to examine the association between neighborhood social cohesion and aerobic leisure-time physical activity (LTPA among Latino adults and to determine whether these associations differ by Latino subgroup. We used cross-sectional 2013–2014 National Health Interview Survey (NHIS data on Latinos originating from 5 countries/regions (i.e., Latinos of Puerto Rican, Mexican/Mexican-American, Cuban/Cuban-American, Dominican and Central or South American origin aged ≥18 years (n=11,126. Multivariable logistic regression models were used to estimate associations between self-reported neighborhood social cohesion and meeting aerobic LTPA guidelines. Models were adjusted for age, sex, education, and acculturation. We also investigated whether associations varied by Latino subgroup. In adjusted models for all Latino adults, compared with those reporting low social cohesion, individuals who reported high social cohesion (Odds Ratio [OR]: 1.33; 95% Confidence Interval [CI]: 1.17–1.52 were significantly more likely to meet the aerobic physical activity guideline. When stratified by Latino subgroups, among Mexican/Mexicans-Americans (OR: 1.39; 95% CI: 1.16, 1.66 and Cuban/Cuban Americans (OR: 1.73; 95% CI: 1.00, 2.97 high social cohesion was associated with meeting the aerobic activity guideline. Among Dominicans, those who reported medium social cohesion (OR: 0.52, 95% CI: 0.29, 0.93 were less likely to meet the aerobic activity guideline. When examining aerobic physical activity outcomes in the Latino population, the role of neighborhood social cohesion and the variability among Latino subgroups should be considered. Keywords: Neighborhood social cohesion, Physical activity, Latinos, subgroups

  13. Stable aerobic granules in continuous-flow bioreactor with self-forming dynamic membrane.

    Science.gov (United States)

    Liu, Hongbo; Li, Yajie; Yang, Changzhu; Pu, Wenhong; He, Liu; Bo, Fu

    2012-10-01

    A novel continuous-flow bioreactor with aerobic granular sludge and self-forming dynamic membrane (CGSFDMBR) was developed for efficient wastewater treatment. Under continuous-flow operation, aerobic granular sludge was successfully cultivated and characterized with small particle size of about 0.1-1.0mm, low settling velocity of about 15-25 m/h, loose structure and high water content of about 96-98%. To maintain the stability of aerobic granular sludge, strategies based on the differences of settling velocity and particle-size between granular and flocculent sludge were implemented. Moreover, in CGSFDMBR, membrane fouling was greatly relieved. Dynamic membrane was just cleaned once in more than 45 days' operation. CGSFDMBR presented good performance in treating septic tank wastewater, obtaining average COD, NH(4)(+)-N, TN and TP removal rates of 83.3%, 73.3%, 67.3% and 60%, respectively, which was more efficient than conventional bioreactors since that carbon, nitrogen and phosphorus were simultaneously removed in a single aerobic reactor. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Plasma inflammatory biomarkers response to aerobic versus ...

    African Journals Online (AJOL)

    Plasma inflammatory biomarkers response to aerobic versus resisted exercise training for chronic obstructive pulmonary disease patients. ... Recent studies proved that morbidity and mortality of COPD is related to systemic inflammation as it contributes to the pathogenesis of atherosclerosis and cardiovascular disease.

  15. Gas-exfoliated porous monolayer boron nitride for enhanced aerobic oxidative desulfurization performance

    Science.gov (United States)

    Wu, Yingcheng; Wu, Peiwen; Chao, Yanhong; He, Jing; Li, Hongping; Lu, Linjie; Jiang, Wei; Zhang, Beibei; Li, Huaming; Zhu, Wenshuai

    2018-01-01

    Hexagonal boron nitride has been regarded to be an efficient catalyst in aerobic oxidation fields, but limited by the less-exposed active sites. In this contribution, we proposed a simple green liquid nitrogen gas exfoliation strategy for preparation of porous monolayer nanosheets (BN-1). Owing to the reduced layer numbers, decreased lateral sizes and artificially-constructed pores, increased exposure of active sites was expected, further contributed to an enhanced aerobic oxidative desulfurization (ODS) performance up to ˜98% of sulfur removal, achieving ultra-deep desulfurization. This work not only introduced an excellent catalyst for aerobic ODS, but also provided a strategy for construction of some other highly-efficient monolayer two-dimensional materials for enhanced catalytic performance.

  16. Steady-state and transient-state analyses of aerobic fermentation in Saccharomyces kluyveri

    DEFF Research Database (Denmark)

    Møller, Kasper; Bro, Christoffer; Piskur, Jure

    2002-01-01

    Some yeasts, such as Saccharomyces cerevisiae, produce ethanol at fully aerobic conditions, whereas other yeasts, such as Kluyveromyces lactis, do not. In this study we investigated the occurrence of aerobic alcoholic fermentation in the petite-negative yeast Saccharomyces kluyveri that is only...... distantly related to S. cerevisiae. In aerobic glucose-limited continuous cultures of S. kluyveri, two growth regimens were observed: at dilution rates below 0.5 h(-1) the metabolism was purely respiratory, and at dilution rates above 0.5 h-1 the metabolism was respiro-fermentative. The dilution rate...... a delay of 20-50 min (depending on culture conditions prior to the pulse), which is in contrast to S. cerevisiae that ferments immediately after glucose addition....

  17. Earlier time to aerobic exercise is associated with faster recovery following acute sport concussion.

    Science.gov (United States)

    Lawrence, David Wyndham; Richards, Doug; Comper, Paul; Hutchison, Michael G

    2018-01-01

    To determine whether earlier time to initiation of aerobic exercise following acute concussion is associated with time to full return to (1) sport and (2) school or work. A retrospective stratified propensity score survival analysis of acute (≤14 days) concussion was used to determine whether time (days) to initiation of aerobic exercise post-concussion was associated with, both, time (days) to full return to (1) sport and (2) school or work. A total of 253 acute concussions [median (IQR) age, 17.0 (15.0-20.0) years; 148 (58.5%) males] were included in this study. Multivariate Cox regression models identified that earlier time to aerobic exercise was associated with faster return to sport and school/work adjusting for other covariates, including quintile propensity strata. For each successive day in delay to initiation of aerobic exercise, individuals had a less favourable recovery trajectory. Initiating aerobic exercise at 3 and 7 days following injury was associated with a respective 36.5% (HR, 0.63; 95% CI, 0.53-0.76) and 73.2% (HR, 0.27; 95% CI, 0.16-0.45) reduced probability of faster full return to sport compared to within 1 day; and a respective 45.9% (HR, 0.54; 95% CI, 0.44-0.66) and 83.1% (HR, 0.17; 95% CI, 0.10-0.30) reduced probability of faster full return to school/work. Additionally, concussion history, symptom severity, LOC deleteriously influenced concussion recovery. Earlier initiation of aerobic exercise was associated with faster full return to sport and school or work. This study provides greater insight into the benefits and safety of aerobic exercise within the first week of the injury.

  18. The relationship between quality of life and aerobic fitness in patients with rheumatoid arthritis.

    Science.gov (United States)

    Chang, Chia-Ling; Chiu, Cheng-Ming; Hung, Su-Ying; Lee, Si-Huei; Lee, Chang-Shun; Huang, Chi-Ming; Chou, Chen-Liang

    2009-06-01

    Aerobic fitness is among the various aspects of rheumatoid arthritis (RA) patients' lives that may deteriorate as a result of the disease and, in doing so, influence patient attitudes toward their own general health. This cross-sectional study examined (1) relationships between patients' aerobic fitness and general health perceptions, (2) relationships between functional aerobic impairment and general health perceptions, (3) the impact of body mass index (BMI) on RA patients' cardiopulmonary functioning. Sixty-six RA patients (ten male and 56 female adults) participated in this study. Following maximum graded exercise tolerance testing to determine their subsequent aerobic fitness, they completed a version of the World Health Organization Quality of Life brief form (WHOQOL-BREF, short form) questionnaire. The one sample t test determined differences between the RA group and the reference data. We used Spearman's correlation analyses to assess the associations between variables of the WHOQOL-BREF questionnaire and patients' aerobic fitness. VO(2 peak) was on average 92.00% +/- 13.37% and 77.93% +/- 20.24% of that predicted for age-matched men and women, respectively. The female patients' BMI was significantly lower than that of the reference data (P self-esteem, body image, and negative feelings) domains for the female patients. It also demonstrated a significant association between the WHOQOL-BREF scores and functional aerobic impairment in the physical (P = 0.006; energy, mobility, activity), psychological (P = 0.008; self-esteem and body images), and environment (P = 0.035; finance, service) domains for the female patients. Our results indicated that impaired aerobic fitness, combined with poor physical and psychological well-being, influenced midlife transition in Taiwanese RA women.

  19. Accelerometer-measured daily physical activity related to aerobic fitness in children and adolescents

    DEFF Research Database (Denmark)

    Dencker, Magnus; Andersen, Lars Bo

    2011-01-01

    Maximum oxygen uptake ([Vdot]O(2PEAK)) is generally considered to be the best single marker for aerobic fitness. While a positive relationship between daily physical activity and aerobic fitness has been established in adults, the relationship appears less clear in children and adolescents...

  20. Development of 1-Mile Walk Tests to Estimate Aerobic Fitness in Children

    Science.gov (United States)

    Sung, Hoyong; Collier, David N.; DuBose, Katrina D.; Kemble, C. David; Mahar, Matthew T.

    2018-01-01

    To examine the reliability and validity of 1-mile walk tests for estimation of aerobic fitness (VO[subscript 2max]) in 10- to 13-year-old children and to cross-validate previously published equations. Participants (n = 61) walked 1-mile on two different days. Self-reported physical activity, demographic variables, and aerobic fitness were used in…

  1. Microwave enhanced digestion of aerobic SBR sludge | Kennedy ...

    African Journals Online (AJOL)

    MWs) for improving characteristics of aerobic sequencing batch reactor (SBR) sludge to enhance mesophilic anaerobic digestion. Effects of pretreatment temperature, MW irradiation intensity and solids concentration on sludge characterisation ...

  2. Biotransformation of phytosterols under aerobic conditions.

    Science.gov (United States)

    Dykstra, Christy M; Giles, Hamilton D; Banerjee, Sujit; Pavlostathis, Spyros G

    2014-07-01

    Phytosterols are plant-derived sterols present in pulp and paper wastewater and have been implicated in the endocrine disruption of aquatic species. Bioassays were performed to assess the effect of an additional carbon source and/or solubilizing agent on the aerobic biotransformation of a mixture of three common phytosterols (β-sitosterol, stigmasterol and campesterol). The aerobic biotransformation of the phytosterol mixture by a mixed culture developed from a pulp and paper wastewater treatment system was examined under three separate conditions: with phytosterols as the sole added carbon source, with phytosterols and dextrin as an additional carbon source, and with phytosterols added with ethanol as an additional carbon source and solubilizing agent. Significant phytosterol removal was not observed in assays set up with phytosterol powder, either with or without an additional carbon source. In contrast, all three phytosterols were aerobically degraded when added as a dissolved solution in ethanol. Thus, under the experimental conditions of this study, the bioavailability of phytosterols was limited without the presence of a solubilizing agent. The total phytosterol removal rate was linear for the first six days before re-spiking, with a rate of 0.47 mg/L-d (R(2) = 0.998). After the second spiking, the total phytosterol removal rate was linear for seven days, with a rate of 0.32 mg/L-d (R(2) = 0.968). Following the 7th day, the phytosterol removal rate markedly accelerated, suggesting two different mechanisms are involved in phytosterol biotransformation, more likely related to the production of enzyme(s) involved in phytosterol degradation, induced under different cell growth conditions. β-sitosterol was preferentially degraded, as compared to stigmasterol and campesterol, although all three phytosterols fell below detection limits by the 24th day of incubation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. The role of biology in planetary evolution: cyanobacterial primary production in low‐oxygen Proterozoic oceans

    Science.gov (United States)

    Bryant, Donald A.; Macalady, Jennifer L.

    2016-01-01

    Summary Understanding the role of biology in planetary evolution remains an outstanding challenge to geobiologists. Progress towards unravelling this puzzle for Earth is hindered by the scarcity of well‐preserved rocks from the Archean (4.0 to 2.5 Gyr ago) and Proterozoic (2.5 to 0.5 Gyr ago) Eons. In addition, the microscopic life that dominated Earth's biota for most of its history left a poor fossil record, consisting primarily of lithified microbial mats, rare microbial body fossils and membrane‐derived hydrocarbon molecules that are still challenging to interpret. However, it is clear from the sulfur isotope record and other geochemical proxies that the production of oxygen or oxidizing power radically changed Earth's surface and atmosphere during the Proterozoic Eon, pushing it away from the more reducing conditions prevalent during the Archean. In addition to ancient rocks, our reconstruction of Earth's redox evolution is informed by our knowledge of biogeochemical cycles catalysed by extant biota. The emergence of oxygenic photosynthesis in ancient cyanobacteria represents one of the most impressive microbial innovations in Earth's history, and oxygenic photosynthesis is the largest source of O 2 in the atmosphere today. Thus the study of microbial metabolisms and evolution provides an important link between extant biota and the clues from the geologic record. Here, we consider the physiology of cyanobacteria (the only microorganisms capable of oxygenic photosynthesis), their co‐occurrence with anoxygenic phototrophs in a variety of environments and their persistence in low‐oxygen environments, including in water columns as well as mats, throughout much of Earth's history. We examine insights gained from both the rock record and cyanobacteria presently living in early Earth analogue ecosystems and synthesize current knowledge of these ancient microbial mediators in planetary redox evolution. Our analysis supports the hypothesis that anoxygenic

  4. The role of biology in planetary evolution: cyanobacterial primary production in low-oxygen Proterozoic oceans.

    Science.gov (United States)

    Hamilton, Trinity L; Bryant, Donald A; Macalady, Jennifer L

    2016-02-01

    Understanding the role of biology in planetary evolution remains an outstanding challenge to geobiologists. Progress towards unravelling this puzzle for Earth is hindered by the scarcity of well-preserved rocks from the Archean (4.0 to 2.5 Gyr ago) and Proterozoic (2.5 to 0.5 Gyr ago) Eons. In addition, the microscopic life that dominated Earth's biota for most of its history left a poor fossil record, consisting primarily of lithified microbial mats, rare microbial body fossils and membrane-derived hydrocarbon molecules that are still challenging to interpret. However, it is clear from the sulfur isotope record and other geochemical proxies that the production of oxygen or oxidizing power radically changed Earth's surface and atmosphere during the Proterozoic Eon, pushing it away from the more reducing conditions prevalent during the Archean. In addition to ancient rocks, our reconstruction of Earth's redox evolution is informed by our knowledge of biogeochemical cycles catalysed by extant biota. The emergence of oxygenic photosynthesis in ancient cyanobacteria represents one of the most impressive microbial innovations in Earth's history, and oxygenic photosynthesis is the largest source of O2 in the atmosphere today. Thus the study of microbial metabolisms and evolution provides an important link between extant biota and the clues from the geologic record. Here, we consider the physiology of cyanobacteria (the only microorganisms capable of oxygenic photosynthesis), their co-occurrence with anoxygenic phototrophs in a variety of environments and their persistence in low-oxygen environments, including in water columns as well as mats, throughout much of Earth's history. We examine insights gained from both the rock record and cyanobacteria presently living in early Earth analogue ecosystems and synthesize current knowledge of these ancient microbial mediators in planetary redox evolution. Our analysis supports the hypothesis that anoxygenic photosynthesis

  5. Aerobic Games and Playful exercises in 9-YearOld Boys: Intensity and Fitness Effects

    Directory of Open Access Journals (Sweden)

    Gunnar E Mathisen

    2016-04-01

    Full Text Available Previous research on exercise for pre-adolescents with the purpose of improving aerobic fitness levels has yielded contradictory results. Sufficient training intensity, frequency and duration are the crucial factors in achieving this goal; the question, however, is whether it is possible to reach sufficient intensity levels using aerobic games and playful exercises. Variety and fun are the important factors in motivating children to participate in physical exercises and sports. Therefore, the aim of the study was to investigate the effect of high intensity exercises in pre-adolescent boys, using programs consisting of fun activities and aerobic games. The findings show that the participants achieved intensity levels above 80 % of HRpeak on average in about 60 % of the total exercise time, resulting in significantly improved aerobic fitness.

  6. Effect of wrist cooling on aerobic and anaerobic performance in elite sportsmen.

    Science.gov (United States)

    Krishnan, Anup; Singh, Krishan; Sharma, Deep; Upadhyay, Vivekanand; Singh, Amit

    2018-01-01

    Body cooling has been used to increase sporting performance and enhance recovery. Several studies have reported improvement in exercise capacities using forearm and hand cooling or only hand cooling. Wrist cooling has emerged as a portable light weight solution for precooling prior to sporting activity. The Astrand test for aerobic performance and the Wingate test for anaerobic performance are reliable and accurate tests for performance assessment. This study conducted on elite Indian athletes analyses the effects of wrist precooling on aerobic and anaerobic performance as tested by the Astrand test and the Wingate test before and after wrist precooling. 67 elite sportsmen were administered Wingate and Astrand test under standardised conditions with and without wrist precooling using a wrist cooling device (dhamaSPORT). Paired t -test was applied to study effect on aerobic [VO 2 (ml/min/kg)] and anaerobic performance [peak power (W/kg) and average power (W/kg)] and Cohen's d was used to calculate effect size of wrist precooling. After wrist precooling, significant increase of 0.22 ( p  = 0.014, 95% CI: 0.047, 0.398) in peak power (W/kg) and 0.22 ( p  effective in aerobic performance. Wrist cooling effect size was smaller in VO 2 (Cohen's d  = 0.21), peak power (Cohen's d  = 0.31) and it was larger in average power (Cohen's d  = 0.71). Results show wrist precooling significantly improves anaerobic than aerobic performance of elite sportsmen.

  7. Integrated anaerobic and aerobic treatment of sewage

    NARCIS (Netherlands)

    Wang, K.

    1994-01-01

    This thesis describes results of investigations dealing with sequential concept of anaerobic-aerobic treatment of municipal wastewater. The main purposes of the study were 1) to develop a proper anaerobic hydrolytic pretreatment unit, consisting of a Hydrolysis Upflow Sludge Bed (HUSB-)

  8. Hydro aerobics as means for physical state improvement of female students

    Directory of Open Access Journals (Sweden)

    N.M. Balamutova

    2013-03-01

    Full Text Available The questions of organization and conducting studies were considered by using system of hydro aerobics exercises for improving physical training of female students. Sixty female students took part in the experiment. All the tested girls were divided into two groups, 30 persons each. The tested group of female students made aerobic exercises on the dry land according to a plan. The female students of experimental group made hydro aerobics exercises according to the programme. Several methods were used: anthropometry, control methods of the functional parameters of the body, testing of the physical training indicators, methods of mathematical statistics. The reliable positive improvements of cardiovascular and respiratory systems were in the experimental group of the girls. The effect of the reliable decrease of fat mass of the tested female students was exposed among anthropometrical characteristics.

  9. Aerobic capacity influences the spatial position of individuals within fish schools

    DEFF Research Database (Denmark)

    Killen, Shaun S.; Marras, Stefano; Steffensen, John Fleng

    2012-01-01

    the rear of schools. These trailing fish required fewer tail beats to swim at the same speed as individuals at the front of schools, indicating that posterior positions provide hydrodynamic benefits that reduce swimming costs. Conversely, fish with high aerobic capacity can withstand increased drag......The schooling behaviour of fish is of great biological importance, playing a crucial role in the foraging and predator avoidance of numerous species. The extent to which physiological performance traits affect the spatial positioning of individual fish within schools is completely unknown. Schools...... of juvenile mullet Liza aurata were filmed at three swim speeds in a swim tunnel, with one focal fish from each school then also measured for standard metabolic rate (SMR), maximal metabolic rate (MMR), aerobic scope (AS) and maximum aerobic swim speed. At faster speeds, fish with lower MMR and AS swam near...

  10. Biological removal of nitrate and ammonium under aerobic atmosphere by Paracoccus versutus LYM.

    Science.gov (United States)

    Shi, Zhuang; Zhang, Yu; Zhou, Jiti; Chen, Mingxiang; Wang, Xiaojun

    2013-11-01

    The bacterium isolated from sea sludge Paracoccus versutus LYM was characterized with the ability of aerobic denitrification. Strain LYM performs perfect activity in aerobically converting over 95% NO3(-)-N (approximate 400mg L(-1)) to gaseous products via nitrite with maximum reduction rate 33 mg NO3(-)-N L(-1) h(-1). Besides characteristic of aerobic denitrification, strain LYM was confirmed in terms of the ability to be heterotrophic nitrification and aerobic denitrification (HNAD) with few accumulations of intermediates. After the nitrogen balance and enzyme assays, the putative nitrogen pathway of HNAD could be NH4(+) → NH2OH → NO2(-)→ NO3(-), then NO3(-) was denitrified to gaseous products via nitrite. N2 was sole denitrification product without any detection of N2O by gas chromatography. Strain LYM could also simultaneously remove ammonium and additional nitrate. Meanwhile, the accumulated nitrite had inhibitory effect on ammonium reduction rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Electric motor assisted bicycle as an aerobic exercise machine.

    Science.gov (United States)

    Nagata, T; Okada, S; Makikawa, M

    2012-01-01

    The goal of this study is to maintain a continuous level of exercise intensity around the aerobic threshold (AT) during riding on an electric motor assisted bicycle using a new control system of electrical motor assistance which uses the efficient pedaling rate of popular bicycles. Five male subjects participated in the experiment, and the oxygen uptake was measured during cycling exercise using this new pedaling rate control system of electrical motor assistance, which could maintain the pedaling rate within a specific range, similar to that in previous type of electrically assisted bicycles. Results showed that this new pedaling rate control system at 65 rpm ensured continuous aerobic exercise intensity around the AT in two subjects, and this intensity level was higher than that observed in previous type. However, certain subjects were unable to maintain the expected exercise intensity because of their particular cycling preferences such as the pedaling rate. It is necessary to adjust the specific pedaling rate range of the electrical motor assist control according to the preferred pedaling rate, so that this system becomes applicable to anyone who want continuous aerobic exercise.

  12. [Aerobic capacity, weight status and self-concept in schoolchildren].

    Science.gov (United States)

    Gálvez Casas, Arancha; Rodríguez García, Pedro Luis; Rosa Guillamón, Andrés; García-Cantó, Eliseo; Pérez Soto, Juan José; Tárraga López, Pedro; Tárraga Marcos, Loreto

    2016-01-01

    To analyze the relationship between self-concept, aerobic capacity and weight status in schoolchildren. Relational descriptive design in which was assessed the weight status and aerobic capacity of 256 schoolchildren among 8-11 years. Aerobic capacity (low vs high) and the body mass index (normal-weight vs overweight-obesity) were categorized using standard criteria. The self-concept was assessed through the Piers Harris self-concept scale for children. Schoolchildren with normal-weight and high fitness level showed better levels of conductual self-concept (P=.030), physical (Pself-concept (P=.002). The schoolchildren with normal-weight show higher levels of conductual self-concpt (P=.016), intellectual (P=.050), physical (Pself-concept (P=.001). The schoolchildren with a higher fitness level showed better conductual self-concept (P=.024), physical (P=.004), lack of anxiety (P=.011), social (P=.024), and global (P=.003). The results of the study strengthen the importance to transmit to the educative community the knowledge of the relationship between the variables analyzed aiming to improve the schoolchildren self-concept. Copyright © 2015 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  13. A randomized 9-month study of blood pressure and body fat responses to aerobic training versus combined aerobic and resistance training in older men.

    Science.gov (United States)

    Sousa, Nelson; Mendes, Romeu; Abrantes, Catarina; Sampaio, Jaime; Oliveira, José

    2013-08-01

    This randomized study evaluated the impact of different exercise training modalities on blood pressure and body fat responses in apparently healthy older men. Forty-eight elderly men (aged 65-75 years) were randomly assigned to an aerobic training group (ATG, n=15), a combined aerobic and resistance training group (CTG, n=16), or a control group (n=17). Both exercise training programs were moderate-to-vigorous intensity, three days/week for 9-months. Strength, aerobic endurance, body fat and blood pressure were measured on five different occasions. The data were analyzed using a mixed-model ANOVA, and the independence between systolic blood pressure (SBP), diastolic blood pressure (DBP) and group was tested. A significant main effect of group (pendurance, with higher performance observed in the CTG. A significant main effect of group (ptraining programs reduce resting blood pressure. However, only the combined exercise training was effective at reducing body fat percentage; consequently, there were larger changes in blood pressure, which result in a significant reduction in hypertensive subjects. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Effects of Exercise Modality During Additional "High-Intensity Interval Training" on Aerobic Fitness and Strength in Powerlifting and Strongman Athletes.

    Science.gov (United States)

    Androulakis-Korakakis, Patroklos; Langdown, Louis; Lewis, Adam; Fisher, James P; Gentil, Paulo; Paoli, Antonio; Steele, James

    2018-02-01

    Androulakis-Korakakis, P, Langdown, L, Lewis, A, Fisher, JP, Gentil, P, Paoli, A, and Steele, J. Effects of exercise modality during additional "high-intensity interval training" on aerobic fitness and strength in powerlifting and strongman athletes. J Strength Cond Res 32(2): 450-457, 2018-Powerlifters and strongman athletes have a necessity for optimal levels of muscular strength while maintaining sufficient aerobic capacity to perform and recover between events. High-intensity interval training (HIIT) has been popularized for its efficacy in improving both aerobic fitness and strength but never assessed within the aforementioned population group. This study looked to compare the effect of exercise modality, e.g., a traditional aerobic mode (AM) and strength mode (SM), during HIIT on aerobic fitness and strength. Sixteen well resistance-trained male participants, currently competing in powerlifting and strongman events, completed 8 weeks of approximately effort- and volume-matched HIIT in 2 groups: AM (cycling, n = 8) and SM (resistance training, n = 8). Aerobic fitness was measured as predicted V[Combining Dot Above]O2max using the YMCA 3 minutes step test and strength as predicted 1 repetition maximum from a 4-6RM test using a leg extension. Both groups showed significant improvements in both strength and aerobic fitness. There was a significant between-group difference for aerobic fitness improvements favoring the AM group (p ≤ 0.05). There was no between-group difference for change in strength. Magnitude of change using within-group effect size for aerobic fitness and strength was considered large for each group (aerobic fitness, AM = 2.6, SM = 2.0; strength, AM = 1.9, SM = 1.9). In conclusion, our results support enhanced strength and aerobic fitness irrespective of exercise modality (e.g., traditional aerobic and resistance training). However, powerlifters and strongman athletes wishing to enhance their aerobic fitness should consider HIIT using an

  15. The role of work ability in the relationship between aerobic capacity and sick leave: A mediation analysis

    NARCIS (Netherlands)

    Strijk, J.E.; Proper, K.I.; Stralen, M.M. van; Wijngaard, P.; Mechelen, W. van; Beek, A.J. van der

    2011-01-01

    Objectives: To examine: (1) the relationships between aerobic capacity, work ability and sick leave; (2) the potential mediating effect of work ability in the relationship between aerobic capacity and sick leave; and (3) the influence of age on these relationships. Methods: Information on aerobic

  16. Characteristics and performance of aerobic algae-bacteria granular consortia in a photo-sequencing batch reactor.

    Science.gov (United States)

    Liu, Lin; Zeng, Zhichao; Bee, Mingyang; Gibson, Valerie; Wei, Lili; Huang, Xu; Liu, Chaoxiang

    2018-05-05

    The characteristics and performance of algae-bacteria granular consortia which cultivated with aerobic granules and targeted algae (Chlorella and Scenedesmus), and the essential difference between granular consortia and aerobic granules were investigated in this experiment. The result indicated that algae-bacteria granular consortia could be successfully developed, and the algae present in the granular consortia were mainly Chlorella and Scenedesmus. Although the change of chlorophyll composition revealed the occurrence of light limitation for algal growth, the granular consortia could maintain stable granular structure, and even showed better settling property than aerobic granules. Total nitrogen and phosphate in the algal-bacterial granular system showed better removal efficiencies (50.2% and 35.7%) than those in the aerobic granular system (32.8% and 25.6%) within one cycle (6 h). The biodiesel yield of aerobic granules could be significantly improved by algal coupled process, yet methyl linolenate and methyl palmitoleate were the dominant composition of biodiesel obtained from granular consortia and aerobic granules, respectively. Meanwhile, the difference of dominant bacterial communities in the both granules was found at the order level and family level, and alpha diversity indexes revealed the granular consortia had a higher microbial diversity. Copyright © 2018. Published by Elsevier B.V.

  17. [Anaerobiosis beyond anaerobic bacteria: its role in the recovery of aerobic microorganisms from purulent samples].

    Science.gov (United States)

    Litterio Bürki, M R; Lopardo, H

    2010-01-01

    The main objective of incubation in anaerobiosis is the recovery of obligate anaerobic bacteria, not excluding other microorganisms. In 2003, we conducted a comparative and prospective study from consecutive clinical samples on the recovery of aerobic microorganisms from primary cultures both in anaerobiosis and aerobiosis of the same sample. The aims were to evaluate the methodology used in anaerobiosis in the recovery of aerobic microorganisms not diagnosed in primary aerobic cultures, and to establish a relationship between them and the origin of the sample. From 2003 to 2004, 2776 bacteriological samples were analyzed and 1884 aerobic microorganisms were cultured altogether. The result was that 69.4% of the samples showed growth both in aerobic and anaerobic incubation from primary cultures of the sample, whereas 30.6% only in one of the mentioned incubation atmosphere: 49.2% in aerobiosis and 50.8% in anaerobiosis. According to these results, the methodology used in anaerobiosis (anaerobic incubation, culture media, stereoscopic microscope or hand lens to examine the primary plates), allowed an extra yield of aerobic organisms, especially gram positive facultative and microaerophilic cocci, which was particularly evident in polimicrobial cultures, and especially when gram negative accompanying flora was present, independently of the type of sample.

  18. Four birds with one stone? Reparative, neuroplastic, cardiorespiratory, and metabolic benefits of aerobic exercise poststroke.

    Science.gov (United States)

    Ploughman, Michelle; Kelly, Liam P

    2016-12-01

    Converging evidence from animal models of stroke and clinical trials suggests that aerobic exercise has effects across multiple targets. The subacute phase is characterized by a period of heightened neuroplasticity when aerobic exercise has the potential to optimize recovery. In animals, low intensity aerobic exercise shrinks lesion size and reduces cell death and inflammation, beginning 24 h poststroke. Also in animals, aerobic exercise upregulates brain-derived neurotrophic factor near the lesion and improves learning. In terms of neuroplastic effects, clinical trial results are less convincing and have only examined effects in chronic stroke. Stroke patients demonstrate cardiorespiratory fitness levels below the threshold required to carry out daily activities. This may contribute to a 'neurorehabilitation ceiling' that limits capacity to practice at a high enough frequency and intensity to promote recovery. Aerobic exercise when delivered 2-5 days per week at moderate to high intensity beginning as early as 5 days poststroke improves cardiorespiratory fitness, dyslipidemia, and glucose tolerance. Based on the evidence discussed and applying principles of periodization commonly used to prepare athletes for competition, we have created a model of aerobic training in subacute stroke in which training is delivered in density blocks (duration × intensity) matched to recovery phases.

  19. Modeling aerobic biodegradation in the capillary fringe.

    Science.gov (United States)

    Luo, Jian; Kurt, Zohre; Hou, Deyi; Spain, Jim C

    2015-02-03

    Vapor intrusion from volatile subsurface contaminants can be mitigated by aerobic biodegradation. Laboratory column studies with contaminant sources of chlorobenzene and a mixture of chlorobenzene, 1,2-dichlorobenzene, and 1,4-dichlorobenzene showed that contaminants were rapidly degraded in thin reactive zones with high biomass and low substrate concentrations in the vicinity of the capillary fringe. Such behavior was well characterized by a model that includes oxygen-, substrate-, and biomass-dependent biodegradation kinetics along with diffusive transport processes. An analytical solution was derived to provide theoretical support for the simplification of reaction kinetics and the approximation of reactive zone location and mass flux relationships at steady state. Results demonstrate the potential of aerobic natural attenuation in the capillary fringe for preventing contaminant migration in the unsaturated zone. The solution indicates that increasing contaminant mass flux into the column creates a thinner reactive zone and pushes it toward the oxygen boundary, resulting in a shorter distance to the oxygen source and a larger oxygen mass flux that balances the contaminant mass flux. As a consequence, the aerobic biodegradation can reduce high contaminant concentrations to low levels within the capillary fringe and unsaturated zone. The results are consistent with the observations of thin reactive layers at the interface in unsaturated zones. The model considers biomass while including biodegradation in the capillary fringe and unsaturated zone and clearly demonstrates that microbial communities capable of using the contaminants as electron donors may lead to instantaneous degradation kinetics in the capillary fringe and unsaturated zone.

  20. Micro-aerobics: when rice plants lose their resistance against oxygen

    International Nuclear Information System (INIS)

    Reuss, J; Harren, F J M

    2008-01-01

    Photoacoustic determination of ethane, ethanol and acetaldehyde releases from 14 d old rice seedlings leads to the conclusion that rice seedlings start suffering significant lipid peroxidation under micro-aerobic conditions. To produce micro-aerobic conditions in otherwise normal atmospheres, the oxygen concentration has been reduced to a value between 0.3 and 0.05% (v/v). The defense of the rice seedlings against oxygenic radicals becomes insufficient under these almost anaerobic conditions. The findings presented here are relevant for the clarification of what causes non-survival of rice seedlings under prolonged submergence.

  1. Microbial fuel cells with highly active aerobic biocathodes

    Science.gov (United States)

    Milner, Edward M.; Popescu, Dorin; Curtis, Tom; Head, Ian M.; Scott, Keith; Yu, Eileen H.

    2016-08-01

    Microbial fuel cells (MFCs), which convert organic waste to electricity, could be used to make the wastewater infrastructure more energy efficient and sustainable. However, platinum and other non-platinum chemical catalysts used for the oxygen reduction reaction (ORR) at the cathode of MFCs are unsustainable due to their high cost and long-term degradation. Aerobic biocathodes, which use microorganisms as the biocatalysts for cathode ORR, are a good alternative to chemical catalysts. In the current work, high-performing aerobic biocathodes with an onset potential for the ORR of +0.4 V vs. Ag/AgCl were enriched from activated sludge in electrochemical half-cells poised at -0.1 and + 0.2 V vs. Ag/AgCl. Gammaproteobacteria, distantly related to any known cultivated gammaproteobacterial lineage, were identified as dominant in these working electrode biofilms (23.3-44.3% of reads in 16S rRNA gene Ion Torrent libraries), and were in very low abundance in non-polarised control working electrode biofilms (0.5-0.7%). These Gammaproteobacteria were therefore most likely responsible for the high activity of biologically catalysed ORR. In MFC tests, a high-performing aerobic biocathode increased peak power 9-fold from 7 to 62 μW cm-2 in comparison to an unmodified carbon cathode, which was similar to peak power with a platinum-doped cathode at 70 μW cm-2.

  2. Association between aerobic fitness and cerebrovascular function with neurocognitive functions in healthy, young adults.

    Science.gov (United States)

    Hwang, Jungyun; Kim, Kiyoung; Brothers, R Matthew; Castelli, Darla M; Gonzalez-Lima, F

    2018-05-01

    Studies of the effects of physical activity on cognition suggest that aerobic fitness can improve cognitive abilities. However, the physiological mechanisms for the cognitive benefit of aerobic fitness are less well understood. We examined the association between aerobic fitness and cerebrovascular function with neurocognitive functions in healthy, young adults. Participants aged 18-29 years underwent measurements of cerebral vasomotor reactivity (CVMR) in response to rebreathing-induced hypercapnia, maximal oxygen uptake (VO 2 max) during cycle ergometry to voluntary exhaustion, and simple- and complex-neurocognitive assessments at rest. Ten subjects were identified as having low-aerobic fitness (LF aerobic fitness (HF > 80th fitness percentile). There were no LF versus HF group differences in cerebrovascular hemodynamics during the baseline condition. Changes in middle cerebral artery blood velocity and CVMR during hypercapnia were elevated more in the HF than the LF group. Compared to the LF, the HF performed better on a complex-cognitive task assessing fluid reasoning, but not on simple attentional abilities. Statistical modeling showed that measures of VO 2 max, CVMR, and fluid reasoning were positively inter-correlated. The relationship between VO 2 max and fluid reasoning, however, did not appear to be reliably mediated by CVMR. In conclusion, a high capacity for maximal oxygen uptake among healthy, young adults was associated with greater CVMR and better fluid reasoning, implying that high-aerobic fitness may promote cerebrovascular and cognitive functioning abilities.

  3. Selective medium for aerobic incubation of Campylobacter

    Science.gov (United States)

    Studies were conducted on the formulation of a selective medium that could be used to isolate Campylobacter from mixed bacterial cultures using aerobic incubation. A non-selective, basal broth medium was prepared and supplemented with Bolton, Cefex, or Skirrow antibiotic mixtures. The ability of pur...

  4. The effect of angiotensin converting enzyme genotype on aerobic capacity following high intensity interval training

    OpenAIRE

    Goddard, N; Baker, M.D; Higgins, T; Cobbold, C

    2014-01-01

    Obesity increases the risk of developing type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Physical activity can reduce T2DM and CVD risk, and increase aerobic capacity, a significant predictor of all-cause mortality and morbidity. High intensity interval training (HIIT) produces similar improvements in aerobic capacity to continuous moderate exercise (CME). Different genotypes of angiotensin converting enzyme (ACE) have been implicated in improving aerobic capacity and theref...

  5. Aerobic dehalogenation activities of two petroleum degrading bacteria

    African Journals Online (AJOL)

    GREGO

    2007-04-02

    Apr 2, 2007 ... Full Length Research Paper. Aerobic ... these compounds are good carbon sources for bacteria capable of ... Degradation of 2, 4-dichlorophenoxyacetic acid using soil .... Such toxic effects of chlorinated aromatic compound.

  6. Effect of grape pomace on fermentation quality and aerobic stability of sweet sorghum silage.

    Science.gov (United States)

    Li, Ping; Shen, Yixin; You, Minghong; Zhang, Yu; Yan, Jiajun; Li, Daxue; Bai, Shiqie

    2017-10-01

    The objective of this study was to evaluate the effect of grape pomace (GP) with different adding levels (0%, 5%, 10% and 15%, fresh matter basis), alone (GP-LAB) or in combine with an inoculant LAB (GP+LAB), on the fermentation quality and aerobic stability of sweet sorghum silage. After 90 days of ensiling in vacuumized mini-silos, silages were subject to a 7-day aerobic stability test, in which chemical, microbial and polyphenol composition were measured. In the GP-LAB group, adding GP decreased (P fermentation. During aerobic exposure, the fungi count, pH value and silage temperature increased (P fermentation products, microbial counts, chemical and polyphenol composition were considered, the use of 10% GP+LAB at ensiling could provide a valuable source for improved fermentation quality and aerobic stability of sweet sorghum silage. © 2017 Japanese Society of Animal Science.

  7. Impaired aerobic work capacity in insulin dependent diabetics with increased urinary albumin excretion

    DEFF Research Database (Denmark)

    Jensen, T; Richter, Erik; Feldt-Rasmussen, Bo

    1988-01-01

    To assess whether decreased aerobic work capacity was associated with albuminuria in insulin dependent diabetics aerobic capacity was measured in three groups of 10 patients matched for age, sex, duration of diabetes, and degree of physical activity. Group 1 comprised 10 patients with normal...... were not explained by differences in metabolic control or the degree of autonomic neuropathy. Thus the insulin dependent diabetics with only slightly increased urinary albumin excretion had an appreciably impaired aerobic work capacity which could not be explained by autonomic neuropathy...... or the duration of diabetes. Whether the reduced capacity is due to widespread microangiopathy or another pathological process affecting the myocardium remains to be established....

  8. Biodegradation of triclosan and formation of methyl-triclosan in activated sludge under aerobic conditions

    DEFF Research Database (Denmark)

    Chen, Xijuan; Nielsen, Jeppe Lund; Furgal, Karolina

    2011-01-01

    of triclosan- methyl was investigated in activated sludge from a standard activated sludge WWTP equipped with enhanced biological phosphorus removal. The removal was found to occur mainly under aerobic conditions while under anoxic (nitrate reducing) and anaerobic conditions rather low removal rates were...... determined. In a laboratory-scale activated sludge reactor 75% of the triclosan was removed under aerobic conditions within 150 h, while no removal was observed under anaerobic or anoxic conditions. One percent of the triclosan was converted to triclosan-methyl under aerobic conditions, less under anoxic...

  9. Kinetics of aerobic oxidation of volatile sulfur compounds in wastewater and biofilm from sewers

    DEFF Research Database (Denmark)

    Rudelle, Elise Alice; Vollertsen, Jes; Hvitved-Jacobsen, Thorkild

    2013-01-01

    Laboratory experiments were conducted to investigate the kinetics of aerobic chemical and biological oxidation of selected odorous volatile sulfur compounds (VSCs) by wastewater and biofilm from sewers. The VSCs included methyl mercaptan (MeSH), ethyl mercaptan (EtSH), dimethyl sulfide (DMS......-spot downstream of a force main and the other was a gravity sewer transporting young aerobic wastewater. The kinetics of VSC oxidation for both wastewater and suspended biofilm samples followed a first-order rate equation. The average values of the reaction rate constants demonstrated the following order...... in the aerobic wastewater....

  10. Visible-Light-Promoted Metal-Free Aerobic Oxidation of Primary Amines to Acids and Lactones.

    Science.gov (United States)

    Cheng, Xiaokai; Yang, Bo; Hu, Xingen; Xu, Qing; Lu, Zhan

    2016-12-05

    A unique metal-free aerobic oxidation of primary amines via visible light photocatalytic double carbon-carbon bonds cleavage and multi carbon-hydrogen bonds oxidation was observed. Aerobic oxidation of primary amines could be controlled to afford acids by using dioxane with 18 W CFL, and lactones by using DMF with 8 W green LEDs, respectively. A plausible mechanism was proposed based on control experiments. This observation showed direct evidences for the fragmentation in the aerobic oxidation of aliphatic primary amines. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Aerobic Exercise: Top 10 Reasons to Get Physical

    Science.gov (United States)

    ... can help you live longer and healthier. Need motivation? See how aerobic exercise affects your heart, lungs ... found that regular physical activity may help protect memory, reasoning, judgment and thinking skills (cognitive function) in ...

  12. [Aerobic methylobacteria as promising objects of modern biotechnology].

    Science.gov (United States)

    Doronina, N V; Toronskava, L; Fedorov, D N; Trotsenko, Yu A

    2015-01-01

    The experimental data of the past decade concerning the metabolic peculiarities of aerobic meth ylobacteria and the prospects for their use in different fields of modern biotechnology, including genetic engineering techniques, have been summarized.

  13. The Effect of Anaerobic and Aerobic Fish Sludge Supernatant on Hydroponic Lettuce

    Directory of Open Access Journals (Sweden)

    Simon Goddek

    2016-06-01

    Full Text Available The mobilization of nutrients from fish sludge (i.e., feces and uneaten feed plays a key role in optimizing the resource utilization and thus in improving the sustainability of aquaponic systems. While several studies have documented the aerobic and anaerobic digestion performance of aquaculture sludge, the impact of the digestate on plant growth has yet to be understood. The present study examines the impact of either an aerobic or an anaerobic digestion effluent on lettuce plant growth, by enriching a mixture of aquaculture and tap water with supernatants from both aerobic and anaerobic batch reactors. The lettuce plants grown in the hydroponic system supplied with supernatant from an anaerobic reactor had significantly better performance with respect to weight gain than both, those in the system where supernatant from the aerobic reactor was added, as well as the control system. It can be hypothesized that this effect was caused by the presence of NH4+ as well as dissolved organic matter, plant growth promoting rhizobacteria and fungi, and humic acid, which are predominantly present in anaerobic effluents. This study should therefore be of value to researchers and practitioners wishing to further develop sludge remineralization in aquaponic systems.

  14. Brucella detection in blood: comparison of the BacT/Alert standard aerobic bottle, BacT/Alert FAN aerobic bottle and BacT/Alert enhanced FAN aerobic bottle in simulated blood culture.

    Science.gov (United States)

    Sümerkan, B; Gökahmetoglu, S; Esel, D

    2001-07-01

    The objective of this study was to compare the performances of the standard aerobic bottle (StAe), FAN aerobic (FANAe) and enhanced FAN aerobic (E-FANAe) (the charcoal component of the FANAe was revised recently to improve the feasibility of Gram smear interpretation) blood culture bottles for BacT/Alert system for the detection of Brucella melitensis in simulated blood culture. Triplicate strains of eight clinical isolates of B. melitensis were studied. Each bottle was inoculated with 5 mL of freshly collected human blood at three different targeted bacterial inocula (10(1), 10(2) and 10(3) CFU/bottle). All bottles were monitored for up to 21 days or until they became positive. The results of time to detection (TTD) on the eight B. melitensis samples were as follows: at 10(1) CFU/bottle, the E-FANAe had a mean TTD significantly shorter than the StAe (48 h vs. 56.2 h, P StAe (41.2 h and 40 h vs. 45.6 h, P StAe, FANAe and E-FANAe were 96, 83 and 58%, respectively. At 10(3) CFU/bottle, the reproducibilities of StAe, FANAe and E-FANAe were 95, 95 and 91%, respectively. Positive results for the presence of bacteria in Gram smears were confirmed in 68% of StAe, 54% of FANAe and 90% of E-FANAe. In case of suspected brucellosis, the combination of one StAe bottle and one E-FANAe bottle seems to provide the highest and fastest recovery of the organism.

  15. Aerobic training does not alter blood pressure in menopausal women with metabolic syndrome.

    Science.gov (United States)

    Lima, Aluísio Henrique Rodrigues de Andrade; Couto, Henrique Eduardo; Cardoso, Glêbia Alexa; Toscano, Lidiane Tavares; Silva, Alexandre Sérgio; Mota, Maria Paula Gonçalves

    2012-11-01

    Arterial Hypertension (AH) is an aggravating condition for Metabolic Syndrome (MS), as well as being aggravated by it. Menopause can make hypertension treatment more difficult, as it favors the worsening of MS components. Although there is evidence that exercise training reduces blood pressure, whether menopause and SM affect the exercise-induced benefits is yet to be elucidated. To compare the effects of aerobic training on blood pressure in non-menopausal and menopausal women with MS METHODS: A total of 44 women were recruited and divided into four groups: non-menopausal control (NMC: 39.5 ± 3.6 years, n = 11); menopausal control (MC: 54.9 ± 5.9 years, n = 12), non-menopausal aerobics (NMA: 43.1 ± 6.8 years, n = 11) and menopausal aerobics (MA: 52.1 ± 5 years, n = 10). The exercise groups performed aerobic training for three months, five times a week, at an intensity between 60% and 70% of heart rate reserve. The resting blood pressure and blood pressure response after 60 minutes of exercise were measured before and after the training period. The two-way ANOVA test was used, considering a p value 0.05). Three months of aerobic training improved MS components, but did not alter resting blood pressure or the BP response after an acute exercise session in women with MS.

  16. Effect of aerobic exercise intervention on DDT degradation and oxidative stress in rats.

    Science.gov (United States)

    Li, Kefeng; Zhu, Xiaohua; Wang, Yuzhan; Zheng, Shuqian; Dong, Guijun

    2017-03-01

    Dichlorodiphenyltrichloroethane (DDT) reportedly causes extensively acute or chronic effects to human health. Exercise can generate positive stress. We evaluated the effect of aerobic exercise on DDT degradation and oxidative stress. Male Wistar rats were randomly assigned into control (C), DDT without exercise training (D), and DDT plus exercise training (DE) groups. The rats were treated as follows: DDT exposure to D and DE groups at the first 2 weeks; aerobic exercise treatment only to the DE group from the 1st day until the rats are killed. DDT levels in excrements, muscle, liver, serum, and hearts were analyzed. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) levels were determined. Aerobic exercise accelerated the degradation of DDT primarily to DDE due to better oxygen availability and aerobic condition and promoted the degradation of DDT. Cumulative oxidative damage of DDT and exercise led to significant decrease of SOD level. Exercise resulted in consistent increase in SOD activity. Aerobic exercise enhanced activities of CAT and GSH-Px and promoted MDA scavenging. Results suggested that exercise can accelerate adaptive responses to oxidative stress and activate antioxidant enzymes activities. Exercise can also facilitate the reduction of DDT-induced oxidative damage and promoted DDT degradation. This study strongly implicated the positive effect of exercise training on DDT-induced liver oxidative stress.

  17. Biodegradation of tributyl phosphate, an organosphate triester, by aerobic granular biofilms

    Energy Technology Data Exchange (ETDEWEB)

    Nancharaiah, Y.V., E-mail: venkatany@gmail.com; Kiran Kumar Reddy, G.; Krishna Mohan, T.V.; Venugopalan, V.P.

    2015-02-11

    Graphical abstract: - Highlights: • Aerobic granular biomass was cultivated by feeding TBP along with acetate. • Rapid biodegradation of TBP when used as a co-substrate or as the sole carbon source. • Biodegradation of 2 mM TBP in 5 h with degradation rate of 0.4 μmol mL{sup −1} h{sup −1}. • High phosphatase activity was observed in TBP-degrading granular biomass. • n-Butanol, hydrolyzed product of TBP, was rapidly metabolized by aerobic granules. - Abstract: Tributyl phosphate (TBP) is commercially used in large volumes for reprocessing of spent nuclear fuel. TBP is a very stable compound and persistent in natural environments and it is not removed in conventional wastewater treatment plants. In this study, cultivation of aerobic granular biofilms in a sequencing batch reactor was investigated for efficient biodegradation of TBP. Enrichment of TBP-degrading strains resulted in efficient degradation of TBP as sole carbon or along with acetate. Complete biodegradation of 2 mM of TBP was achieved within 5 h with a degradation rate of 0.4 μmol mL{sup −1} h{sup −1}. TBP biodegradation was accompanied by release of inorganic phosphate in stoichiometric amounts. n-Butanol, hydrolysed product of TBP was rapidly biodegraded. But, dibutyl phosphate, a putative intermediate of TBP degradation was only partially degraded pointing to an alternative degradation pathway. Phosphatase activity was 22- and 7.5-fold higher in TBP-degrading biofilms as compared to bioflocs and acetate-fed aerobic granules. Community analysis by terminal restriction length polymorphism revealed presence of 30 different bacterial strains. Seven bacterial stains, including Sphingobium sp. a known TBP degrader were isolated. The results show that aerobic granular biofilms are promising for treatment of TBP-bearing wastes or ex situ bioremediation of TBP-contaminated sites.

  18. Biodegradation of tributyl phosphate, an organosphate triester, by aerobic granular biofilms

    International Nuclear Information System (INIS)

    Nancharaiah, Y.V.; Kiran Kumar Reddy, G.; Krishna Mohan, T.V.; Venugopalan, V.P.

    2015-01-01

    Graphical abstract: - Highlights: • Aerobic granular biomass was cultivated by feeding TBP along with acetate. • Rapid biodegradation of TBP when used as a co-substrate or as the sole carbon source. • Biodegradation of 2 mM TBP in 5 h with degradation rate of 0.4 μmol mL −1 h −1 . • High phosphatase activity was observed in TBP-degrading granular biomass. • n-Butanol, hydrolyzed product of TBP, was rapidly metabolized by aerobic granules. - Abstract: Tributyl phosphate (TBP) is commercially used in large volumes for reprocessing of spent nuclear fuel. TBP is a very stable compound and persistent in natural environments and it is not removed in conventional wastewater treatment plants. In this study, cultivation of aerobic granular biofilms in a sequencing batch reactor was investigated for efficient biodegradation of TBP. Enrichment of TBP-degrading strains resulted in efficient degradation of TBP as sole carbon or along with acetate. Complete biodegradation of 2 mM of TBP was achieved within 5 h with a degradation rate of 0.4 μmol mL −1 h −1 . TBP biodegradation was accompanied by release of inorganic phosphate in stoichiometric amounts. n-Butanol, hydrolysed product of TBP was rapidly biodegraded. But, dibutyl phosphate, a putative intermediate of TBP degradation was only partially degraded pointing to an alternative degradation pathway. Phosphatase activity was 22- and 7.5-fold higher in TBP-degrading biofilms as compared to bioflocs and acetate-fed aerobic granules. Community analysis by terminal restriction length polymorphism revealed presence of 30 different bacterial strains. Seven bacterial stains, including Sphingobium sp. a known TBP degrader were isolated. The results show that aerobic granular biofilms are promising for treatment of TBP-bearing wastes or ex situ bioremediation of TBP-contaminated sites

  19. [Treatment of aerobic vaginitis and clinically uncertain causes of vulvovaginal discomfort].

    Science.gov (United States)

    Cepický, P; Malina, J; Kuzelová, M

    2003-11-01

    The treatment of clinically uncertain conditions of vaginal discomforts with a mixed preparation of nifuratel + nystatin (Macmiror complex) and the relation of uncertain conditions to aerobic vaginitis. A prospective study. Gynecology-Obstetrics Outpatient Department LEVRET Ltd., AescuLab Ltd., Laboratory of Microbiology, Prague. 50 women with vaginal discomfort, causes of which had not been clarified by gynecological examination, determination of pH and the amine test, were examined by vaginal smears using microscopy. The results were evaluated in relation to aerobic vaginitis in a pure form or in combination with other nosological units. The authors also evaluated results of therapy by oral nifuratel (Macmiror tbl) 3 x 200 mg daily and a vaginal combined preparation containing nifuratel 500 mg + nystatin 200 kIU (Macmiror complex 500 glo vag) for the period of 7 days. In 50 women candida was demonstrated 24 times, presence of key cells 11 times, lactobacillus nine times with more than 50 in the field, six women were affected by aerobic vaginitis. In all these cases the pH was 4.8 or higher, leukocytes were significantly represented in all cases (> 15 in the field), as well as gram-negative bacteria and/or cocci (> 30 in the field), indicating a combined picture of mycosis, anaerobic vaginosis or lactobacillosis with aerobic vaginitis. The therapy was successful in all cases, the relapse of complaints during one month occurred in three cases. Aerobic vaginitis in a pure form or with anaerobic vaginosis, mycosis or lactobacillosis is frequently concealed under clinically uncertain pictures of vulvo-vaginal discomfort. The therapy by a combination of nifurated 3 x 200 mg orally together with the combined vaginal preparation nifuratel 500 mg + nystatin 200 kIU for the period of 7 days exerts high effect and a low number of relapses.

  20. Psychobiological Responses to Aerobic Exercise in Individuals With Posttraumatic Stress Disorder.

    Science.gov (United States)

    Crombie, Kevin M; Brellenthin, Angelique G; Hillard, Cecilia J; Koltyn, Kelli F

    2018-02-01

    Previous reports have shown improvements in mood and increases in endocannabinoids in healthy adults following a session of aerobic exercise, but it is unclear whether adults with posttraumatic stress disorder (PTSD) experience similar responses. The purpose of this study was to examine psychobiological responses (plasma endocannabinoids [eCBs], mood, and pain) to aerobic exercise in a sample of adults with a diagnosis of PTSD (n = 12) and healthy controls (n = 12). Participants engaged in an aerobic exercise session in which they ran on a treadmill for 30 min at a moderate intensity (70 to 75% maximum heart rate [MHR]). Results indicated improvements in mood states and reductions in pain for both groups following exercise, ds = 0.19 to 1.53. Circulating concentrations of N-arachidonylethanolamine (AEA), 2-arachidonoylglycerol (2-AG), and oleoylethanolamide (OEA) significantly increased (ps = .000 to .050) following the aerobic exercise session for both groups. There were no significant time, group, or interaction effects (ps = .062 to .846) for palmitoylethanolamide (PEA) and 2-oleoylglycerol (2-OG). Although eCBs increased significantly for both groups, within-group effect size calculations indicated the healthy controls experienced a greater magnitude of change for AEA when compared with adults with PTSD, d = 1.21 and d = 0.45, respectively; as well as for 2-AG, d = 0.43 and d = 0.21, respectively. The findings from this study indicated that adults with and without PTSD reported significant mood improvements following 30 min of moderate-intensity aerobic exercise. In addition, the endocannabinoid system was activated in adults with and without PTSD, although effect sizes suggest that adults with PTSD may have a blunted endocannabinoid response to exercise. Copyright © 2018 International Society for Traumatic Stress Studies.

  1. Different types of exercise in Multiple Sclerosis: Aerobic exercise or Pilates, a single-blind clinical study.

    Science.gov (United States)

    Kara, Bilge; Küçük, Fadime; Poyraz, Esra Coşkuner; Tomruk, Melda Soysal; İdıman, Egemen

    2017-01-01

    The aim of our study is to examine effects of aerobic and Pilates exercises on disability, cognition, physical performance, balance, depression and fatigue in relapsing-remitting Multiple Sclerosis (MS) patients as compared to healthy controls. The subjects were divided as aerobic exercise (n = 26), Pilates (n = 9), and the healthy control group (n = 21). We used MSFC, physical performance, Berg balance scale, Beck depression scale, fatigue impact scale. All evaluations were performed before and after exercise training. There are statistically meaningful differences between Nine hole testing, PASAT 3, physical performance and fatique impact scale before and after aerobic exercise. Also we found significant difference for physical performance in the Pilates group. There are no significant differences in measures of fatique impact scale and depression between aerobic exercise group and the healthy controls after exercise. We found significant differences between Pilates and control group's after measurements except depression. There were significant differences between the Pilates and aerobic group for cognitive tests in favor of the Pilates group. Aerobic exercise and clinical Pilates exercises revealed moderate changes in levels of cognitive, physical performance, balance, depression, fatigue in MS patients.

  2. Pyrosequencing reveals the microbial communities in the Red Sea sponge Carteriospongia foliascens and their impressive shifts in abnormal tissues.

    Science.gov (United States)

    Gao, Zhao-Ming; Wang, Yong; Lee, On On; Tian, Ren-Mao; Wong, Yue Him; Bougouffa, Salim; Batang, Zenon; Al-Suwailem, Abdulaziz; Lafi, Feras F; Bajic, Vladimir B; Qian, Pei-Yuan

    2014-10-01

    Abnormality and disease in sponges have been widely reported, yet how sponge-associated microbes respond correspondingly remains inconclusive. Here, individuals of the sponge Carteriospongia foliascens under abnormal status were collected from the Rabigh Bay along the Red Sea coast. Microbial communities in both healthy and abnormal sponge tissues and adjacent seawater were compared to check the influences of these abnormalities on sponge-associated microbes. In healthy tissues, we revealed low microbial diversity with less than 100 operational taxonomic units (OTUs) per sample. Cyanobacteria, affiliated mainly with the sponge-specific species "Candidatus Synechococcus spongiarum," were the dominant bacteria, followed by Bacteroidetes and Proteobacteria. Intraspecies dynamics of microbial communities in healthy tissues were observed among sponge individuals, and potential anoxygenic phototrophic bacteria were found. In comparison with healthy tissues and the adjacent seawater, abnormal tissues showed dramatic increase in microbial diversity and decrease in the abundance of sponge-specific microbial clusters. The dominated cyanobacterial species Candidatus Synechococcus spongiarum decreased and shifted to unspecific cyanobacterial clades. OTUs that showed high similarity to sequences derived from diseased corals, such as Leptolyngbya sp., were found to be abundant in abnormal tissues. Heterotrophic Planctomycetes were also specifically enriched in abnormal tissues. Overall, we revealed the microbial communities of the cyanobacteria-rich sponge, C. foliascens, and their impressive shifts under abnormality.

  3. Aerobic exercise capacity in post-polio syndrome

    NARCIS (Netherlands)

    Voorn, E.L.

    2015-01-01

    The aim of this thesis was to expand the body of knowledge on the diminished aerobic capacity of individuals with post-polio syndrome (PPS). The studies described in this thesis were based on the assumption that, besides a reduced muscle mass, deconditioning contributes to the severely diminished

  4. The lipid response of aerobic marine methanotroph communities under changing environmental conditions.

    Science.gov (United States)

    Rush, D.; Villanueva, L.; van der Meer, M.; S Sinninghe Damsté, J.

    2017-12-01

    Methane (CH4) originating from marine environments accounts for a significant amount of atmospheric greenhouse gas. Aerobic methanotrophs, which convert CH4 to CO­2, are responsible for quenching a part of this methane before its release. Modern-day climate projections show a rapid shift towards a warmer, more acidic ocean. How do these important methanotrophic communities respond to such changes to their environment? Here, we present the results of microcosm experiments from three marine regions influenced by CH4. Particulate organic matter and sediment were collected from the Black Sea, the Baltic Sea, and the North Sea, at depths ideal for aerobic methanotroph communities at the time of sampling (e.g. oxic, in area of active CH4 release). These were incubated under different temperatures, pHs, and labelled 13CH4 concentrations. We monitored methane concentration in these microcosms as an indication of 13CH4 consumption by methanotrophs. Once the methane concentration was lipids of the organisms oxidising methane in order to elucidate which organisms are performing methane oxidation and whether they synthesize specific biomarker lipids. Particular attention will be paid to the abundances and diversity of bacteriohopanepolyol lipids, known methanotroph biomarkers. The ultimate goal of our investigation is to determine the effect changes in these environmental parameters have on aerobic methanotroph community structures and their lipid fingerprints. By establishing reliable biomarker lipids for aerobic methanotrophy at certain conditions, we will then be able to investigate the contribution of aerobic methanotrophy throughout Earth's history, especially at times when CH4 concentrations were higher than they are at present.

  5. Dosing method of physical activity in aerobics classes for students

    Directory of Open Access Journals (Sweden)

    Yu.I. Beliak

    2014-10-01

    Full Text Available Purpose : reasons for the method of dosing of physical activity in aerobics classes for students. The basis of the method is the evaluation of the metabolic cost of funds used in them. Material : experiment involved the assessment of the pulse response of students to load complexes classical and step aerobics (n = 47, age 20-23 years. In complexes used various factors regulating the intensity: perform combinations of basic steps, involvement of movements with his hands, holding in hands dumbbells weighing 1kg increase in the rate of musical accompaniment, varying heights step platform. Results . on the basis of the relationship between heart rate and oxygen consumption was determined by the energy cost of each admission control load intensity. This indicator has been used to justify the intensity and duration of multiplicity aerobics. Figure correspond to the level of physical condition and motor activity deficits students. Conclusions : the estimated component of this method of dosing load makes it convenient for use in automated computer programs. Also it can be easily modified to dispense load other types of recreational fitness.

  6. Stabilisation of microalgae: Iodine mobilisation under aerobic and anaerobic conditions.

    Science.gov (United States)

    Han, Wei; Clarke, William; Pratt, Steven

    2015-10-01

    Mobilisation of iodine during microalgae stabilisation was investigated, with the view of assessing the potential of stabilised microalgae as an iodine-rich fertiliser. An iodine-rich waste microalgae (0.35 ± 0.05 mg I g(-1) VS(added)) was stabilised under aerobic and anaerobic conditions. Iodine mobilisation was linearly correlated with carbon emission, indicating iodine was in the form of organoiodine. Comparison between iodine and nitrogen mobilisation relative to carbon emission indicated that these elements were, at least in part, housed separately within the cells. After stabilisation, there were 0.22 ± 0.05 and 0.19 ± 0.01 mg g(-1) VS(added) iodine remaining in the solid in the aerobic and anaerobic processed material respectively, meaning 38 ± 5.0% (aerobic) and 50 ± 8.6% (anaerobic) of the iodine were mobilised, and consequently lost from the material. The iodine content of the stabilised material is comparable to the iodine content of some seaweed fertilisers, and potentially satisfies an efficient I-fertilisation dose. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Innovative dual-step management of semi-aerobic landfill in a tropical climate.

    Science.gov (United States)

    Lavagnolo, Maria Cristina; Grossule, Valentina; Raga, Roberto

    2018-04-01

    Despite concerted efforts to innovate the solid waste management (SWM) system, land disposal continues to represent the most widely used technology in the treatment of urban solid waste worldwide. On the other hand, landfilling is an unavoidable step in closing the material cycle, since final residues, although minimized, need to be safely disposed of and confined. In recent years, the implementation of more sustainable landfilling aims to achieve the Final Storage Quality conditions as fast as possible. In particular, semi-aerobic landfill appears to represent an effective solution for use in the poorest economies due to lower management costs and shorter aftercare resulting from aerobic stabilisation of the waste. Nevertheless, the implementation of a semi-aerobic landfill in a tropical climate may affect the correct functioning of the plant: a lack of moisture during the dry season and heavy rainfalls during the wet season could negatively affect performance of both the degradation process, and of leachate and biogas management. This paper illustrates the results obtained through the experimentation of a potential dual-step management of semi-aerobic landfilling in a tropical climate in which composting process was reproduced during the dry season and subsequently flushing (high rainfall rate) during the wet period. Eight bioreactors specifically designed: four operated under anaerobic conditions and four under semi-aerobic conditions; half of the reactors were filled with high organic content waste, half with residual waste obtained following enhanced source segregation. The synergic effect of the subsequent phases (composting and flushing) in the semi-aerobic landfill was evaluated on the basis of both types of waste. Biogas production, leachate composition and waste stabilization were analysed during the trial and at the end of each step, and compared in view of the performance of anaerobic reactors. The results obtained underlined the effectiveness of the

  8. Aerobic fitness and performance in elite female futsal players

    Directory of Open Access Journals (Sweden)

    JC Barbero-Alvarez

    2016-01-01

    Full Text Available Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET, until volitional fatigue. Outcome variables were exercise heart rate (HR, VO2, post-exercise blood lactate concentrations ([La]b and running speeds (km • h -2 . During the treadmill test, VO2max, maximal aerobic speed (MAS, HR and peak [La]b were 45.3±5.6 ml • kg-1 • min-1, 12.5±1.77 km • h -2 , 197±8 beats • min-1 and 11.3±1.4 mmol • l-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km • h -2 , 199±8 beats • min-1 and 2.5±2.2 mmol • l-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p<0.0001 with VO2max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players.

  9. Evolution of Molybdenum Nitrogenase during the Transition from Anaerobic to Aerobic Metabolism

    Science.gov (United States)

    Boyd, Eric S.; Costas, Amaya M. Garcia; Hamilton, Trinity L.; Mus, Florence

    2015-01-01

    ABSTRACT Molybdenum nitrogenase (Nif), which catalyzes the reduction of dinitrogen to ammonium, has modulated the availability of fixed nitrogen in the biosphere since early in Earth's history. Phylogenetic evidence indicates that oxygen (O2)-sensitive Nif emerged in an anaerobic archaeon and later diversified into an aerobic bacterium. Aerobic bacteria that fix N2 have adapted a number of strategies to protect Nif from inactivation by O2, including spatial and temporal segregation of Nif from O2 and respiratory consumption of O2. Here we report the complement of Nif-encoding genes in 189 diazotrophic genomes. We show that the evolution of Nif during the transition from anaerobic to aerobic metabolism was accompanied by both gene recruitment and loss, resulting in a substantial increase in the number of nif genes. While the observed increase in the number of nif genes and their phylogenetic distribution are strongly correlated with adaptation to utilize O2 in metabolism, the increase is not correlated with any of the known O2 protection mechanisms. Rather, gene recruitment appears to have been in response to selective pressure to optimize Nif synthesis to meet fixed N demands associated with aerobic productivity and to more efficiently regulate Nif under oxic conditions that favor protein turnover. Consistent with this hypothesis, the transition of Nif from anoxic to oxic environments is associated with a shift from posttranslational regulation in anaerobes to transcriptional regulation in obligate aerobes and facultative anaerobes. Given that fixed nitrogen typically limits ecosystem productivity, our observations further underscore the dynamic interplay between the evolution of Earth's oxygen, nitrogen, and carbon biogeochemical cycles. IMPORTANCE Molybdenum nitrogenase (Nif), which catalyzes the reduction of dinitrogen to ammonium, has modulated the availability of fixed nitrogen in the biosphere since early in Earth's history. Nif emerged in an anaerobe and

  10. Evolution of molybdenum nitrogenase during the transition from anaerobic to aerobic metabolism.

    Science.gov (United States)

    Boyd, Eric S; Costas, Amaya M Garcia; Hamilton, Trinity L; Mus, Florence; Peters, John W

    2015-05-01

    Molybdenum nitrogenase (Nif), which catalyzes the reduction of dinitrogen to ammonium, has modulated the availability of fixed nitrogen in the biosphere since early in Earth's history. Phylogenetic evidence indicates that oxygen (O2)-sensitive Nif emerged in an anaerobic archaeon and later diversified into an aerobic bacterium. Aerobic bacteria that fix N2 have adapted a number of strategies to protect Nif from inactivation by O2, including spatial and temporal segregation of Nif from O2 and respiratory consumption of O2. Here we report the complement of Nif-encoding genes in 189 diazotrophic genomes. We show that the evolution of Nif during the transition from anaerobic to aerobic metabolism was accompanied by both gene recruitment and loss, resulting in a substantial increase in the number of nif genes. While the observed increase in the number of nif genes and their phylogenetic distribution are strongly correlated with adaptation to utilize O2 in metabolism, the increase is not correlated with any of the known O2 protection mechanisms. Rather, gene recruitment appears to have been in response to selective pressure to optimize Nif synthesis to meet fixed N demands associated with aerobic productivity and to more efficiently regulate Nif under oxic conditions that favor protein turnover. Consistent with this hypothesis, the transition of Nif from anoxic to oxic environments is associated with a shift from posttranslational regulation in anaerobes to transcriptional regulation in obligate aerobes and facultative anaerobes. Given that fixed nitrogen typically limits ecosystem productivity, our observations further underscore the dynamic interplay between the evolution of Earth's oxygen, nitrogen, and carbon biogeochemical cycles. Molybdenum nitrogenase (Nif), which catalyzes the reduction of dinitrogen to ammonium, has modulated the availability of fixed nitrogen in the biosphere since early in Earth's history. Nif emerged in an anaerobe and later diversified into

  11. Physical health of young and middle age women under influence of step-aerobics exercises

    Directory of Open Access Journals (Sweden)

    I.P. Masliak

    2015-10-01

    Full Text Available Purpose: to determine the degree of step-aerobics exercises’ influence on 20-35 years age women’s health. Material: in the research 28 women of 20-35 years old age participated. Anthropometric indicators, heart beats rate in rest and after load (20 squats for 30 sec., blood pressure, vital capacity of lungs, hand dynamometry were registered. Results: level of physical health has been determined; influence of step-aerobics on women’s health has been found; age differences in the tested indicators have been analyzed. It was found out that step-aerobic trainings influence greatly on the following indicators: body mass, circumferential sizes and cardio vascular system; on functioning of respiratory system, strength of hand’s flexors and regulation of 31-35 years age women’s cardio-vascular system. Conclusions: application of step-aerobic exercises positively influenced on health of 20-35 years old women.

  12. 1Interaction between serum BDNF and aerobic fitness predicts recognition memory in healthy young adults

    Science.gov (United States)

    Whiteman, Andrew; Young, Daniel E.; He, Xuemei; Chen, Tai C.; Wagenaar, Robert C.; Stern, Chantal; Schon, Karin

    2013-01-01

    Convergent evidence from human and non-human animal studies suggests aerobic exercise and increased aerobic capacity may be beneficial for brain health and cognition. It is thought growth factors may mediate this putative relationship, particularly by augmenting plasticity mechanisms in the hippocampus, a brain region critical for learning and memory. Among these factors, glucocorticoids, brain derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor (VEGF), hormones that have considerable and diverse physiological importance, are thought to effect normal and exercise-induced hippocampal plasticity. Despite these predictions, relatively few published human studies have tested hypotheses that relate exercise and fitness to the hippocampus, and none have considered the potential links to all of these hormonal components. Here we present cross-sectional data from a study of recognition memory; serum BDNF, cortisol, IGF-1, and VEGF levels; and aerobic capacity in healthy young adults. We measured circulating levels of these hormones together with performance on a recognition memory task, and a standard graded treadmill test of aerobic fitness. Regression analyses demonstrated BDNF and aerobic fitness predict recognition memory in an interactive manner. In addition, IGF-1 was positively associated with aerobic fitness, but not with recognition memory. Our results may suggest an exercise adaptation-related change in the BDNF dose-response curve that relates to hippocampal memory. PMID:24269495

  13. Aerobic methanotrophic communities at the Red Sea brine-seawater interface

    Directory of Open Access Journals (Sweden)

    Rehab Z. Abdallah

    2014-09-01

    Full Text Available The central rift of the Red Sea contains 25 brine pools with different physicochemical conditions, dictating the diversity and abundance of the microbial community. Three of these pools, the Atlantis II, Kebrit and Discovery Deeps, are uniquely characterized by a high concentration of hydrocarbons. The brine-seawater interface, described as an anoxic-oxic (brine-seawater boundary, is characterized by a high methane concentration, thus favoring aerobic methane oxidation. The current study analyzed the aerobic free–living methane-oxidizing bacterial communities that potentially contribute to methane oxidation at the brine-seawater interfaces of the three aforementioned brine pools, using metagenomic pyrosequencing, 16S rRNA pyrotags and pmoA library constructs. The sequencing of 16S rRNA pyrotags revealed that these interfaces are characterized by high microbial community diversity. Signatures of aerobic methane-oxidizing bacteria were detected in the Atlantis II Interface (ATII-I and the Kebrit Deep Upper (KB-U and Lower (KB-L brine-seawater interfaces. Through phylogenetic analysis of pmoA, we further demonstrated that the ATII-I aerobic methanotroph community is highly diverse. We propose four ATII-I pmoA clusters. Most importantly, cluster 2 groups with marine methane seep methanotrophs, and cluster 4 represent a unique lineage of an uncultured bacterium with divergent alkane monooxygenases. Moreover, non-metric multidimensional scaling (NMDS based on the ordination of putative enzymes involved in methane metabolism showed that the Kebrit interface layers were distinct from the ATII-I and DD-I brine-seawater interfaces.

  14. Combination of aerobic exercise and Hibiscus sabdariffa Linn. increased nitric oxide in rats

    Directory of Open Access Journals (Sweden)

    Donna Adriani Kusumadewi Muhammad

    2017-08-01

    Full Text Available Background Hypertension and myocardial infarction account for the high rate of mortality globally. Hibiscus sabdariffa (HS Linn. is rich in antioxidants and previous studies have demonstrated its anti-hypertensive effects. Several studies show that regular physical activity is an important component to reduce cardiovascular mortality. The objective of this study was to evaluate the effects of a combination of aerobic exercise and HS extract on nitric oxide (NO and endothelin-1 (ET-1 in rats.   Methods An experimental study was conducted on 36 male Wistar rats, aged 4 weeks and 60-70 g in weight. The interventions were aerobic exercises and HS at 400 mg/kg BW/day administered for 4, 8 and 12 weeks. The rats were randomized into 12 groups: 3 control groups (C4, C8, C12, 3 aerobic exercise groups (A4, A8, A12, 3 HS groups (H4, H8, H12, and 3 combination groups [aerobic exercise and HS] (HA4, HA8, HA12. After 4, 8, and 12 weeks, the rats were sacrificed and their abdominal aorta was collected for determination of nitric oxide and ET-1 concentrations. One way ANOVA was used to analyze the data.   Results There was a significant difference in NO levels between all groups, with the 4-week aerobic exercise group (A4 showing the highest NO levels compared to the other eleven groups (p<0.05. In contrast, the ET-1 levels were not significantly different between all groups.   Conclusions This study demonstrated that the combination of HS supplementation and aerobic exercise increases NO in rats, and provided further evidence to the traditional use of the plant as an antioxidants agent.

  15. Use of aerobic spores as a surrogate for cryptosporidium oocysts in drinking water supplies.

    Science.gov (United States)

    Headd, Brendan; Bradford, Scott A

    2016-03-01

    Waterborne illnesses are a growing concern among health and regulatory agencies worldwide. The United States Environmental Protection Agency has established several rules to combat the contamination of water supplies by cryptosporidium oocysts, however, the detection and study of cryptosporidium oocysts is hampered by methodological and financial constraints. As a result, numerous surrogates for cryptosporidium oocysts have been proposed by the scientific community and efforts are underway to evaluate many of the proposed surrogates. The purpose of this review is to evaluate the suitability of aerobic bacterial spores to serve as a surrogate for cryptosporidium oocysts in identifying contaminated drinking waters. To accomplish this we present a comparison of the biology and life cycles of aerobic spores and oocysts and compare their physical properties. An analysis of their surface properties is presented along with a review of the literature in regards to the transport, survival, and prevalence of aerobic spores and oocysts in the saturated subsurface environment. Aerobic spores and oocysts share many commonalities with regard to biology and survivability, and the environmental prevalence and ease of detection make aerobic spores a promising surrogate for cryptosporidium oocysts in surface and groundwater. However, the long-term transport and release of aerobic spores still needs to be further studied, and compared with available oocyst information. In addition, the surface properties and environmental interactions of spores are known to be highly dependent on the spore taxa and purification procedures, and additional research is needed to address these issues in the context of transport. Published by Elsevier Ltd.

  16. Acute effects of repeated bouts of aerobic exercise on arterial stiffness after glucose ingestion.

    Science.gov (United States)

    Kobayashi, Ryota; Hashimoto, Yuto; Hatakeyama, Hiroyuki; Okamoto, Takanobu

    2018-03-22

    The aim of this study was to investigate the acute repeated bouts of aerobic exercise decrease leg arterial stiffness. However, the influence of repeated bouts of aerobic exercise on arterial stiffness after glucose ingestion is unknown. The present study investigates the acute effects of repeated bouts of aerobic exercise on arterial stiffness after the 75-g oral glucose tolerance test (OGTT). Ten healthy young men (age, 23.2 ± 0.9 years) performed repeated bouts of aerobic exercise trial (RE, 65% peak oxygen uptake; two 15 min bouts of cycling performed 20 min apart) and control trial (CON, seated and resting in a quiet room) at 80 min before the 75-g OGTT on separate days in a randomized, controlled crossover fashion. Carotid-femoral (aortic) and femoral-ankle (leg) pulse wave velocity, carotid augmentation index, brachial and ankle blood pressure, heart rate and blood glucose and insulin levels were measured before (baseline) and 30, 60 and 120 min after the 75-g OGTT. Leg pulse wave velocity, ankle systolic blood pressure and blood glucose levels increased from baseline after the 75-g OGTT in the CON trial, but not in the RE trial. The present findings indicate that acute repeated bouts of aerobic exercise before glucose ingestion suppress increases in leg arterial stiffness following glucose ingestion. RE trial repeated bouts of aerobic exercise trial; CON trial control trial; BG blood glucose; VO 2peak peak oxygen uptake; PWV Pulse wave velocity; AIx carotid augmentation index; BP blood pressure; HR heart rate; CVs coefficients of variation; RPE Ratings of perceived exertion; SE standard error.

  17. Does aerobic exercise increase 24-hour ambulatory blood pressure among workers with high occupational physical activity? - A RCT

    DEFF Research Database (Denmark)

    Korshøj, Mette; Krause, Niklas; Clays, Els

    2017-01-01

    .9–3.8). Cleaners with high aerobic workload exhibited particularly high 24-hour ABP increases: systolic 6.0 mm Hg (95% CI 2.4–9.6), and diastolic 3.8 mm Hg (95% CI 1.3–6.4). CONCLUSION Aerobic exercise increased 24-hour ABP among cleaners. This adverse effect raises questions about the safety and intended benefits......OBJECTIVE High occupational physical activity (OPA) increases cardiovascular risk and aerobic exercise has been recommended for reducing this risk. This paper investigates the effects of an aerobic exercise intervention on 24-hour ambulatory blood pressure (ABP) among cleaners with high OPA....... METHODS Hundred and sixteen cleaners between 18 and 65 years were randomized. During the 4-month intervention period, the aerobic exercise group (AE) (n = 57) performed worksite aerobic exercise (2 × 30 minutes/week), while the reference group (REF) (n = 59) attended lectures. Between-group differences...

  18. Does Aerobic Exercise Increase 24-Hour Ambulatory Blood Pressure Among Workers With High Occupational Physical Activity? - A RCT

    DEFF Research Database (Denmark)

    Korshøj, Mette; Krause, Niklas; Clays, Els

    2017-01-01

    .9–3.8). Cleaners with high aerobic workload exhibited particularly high 24-hour ABP increases: systolic 6.0 mm Hg (95% CI 2.4–9.6), and diastolic 3.8 mm Hg (95% CI 1.3–6.4). CONCLUSION Aerobic exercise increased 24-hour ABP among cleaners. This adverse effect raises questions about the safety and intended benefits......OBJECTIVE High occupational physical activity (OPA) increases cardiovascular risk and aerobic exercise has been recommended for reducing this risk. This paper investigates the effects of an aerobic exercise intervention on 24-hour ambulatory blood pressure (ABP) among cleaners with high OPA....... METHODS Hundred and sixteen cleaners between 18 and 65 years were randomized. During the 4-month intervention period, the aerobic exercise group (AE) (n = 57) performed worksite aerobic exercise (2 × 30 minutes/week), while the reference group (REF) (n = 59) attended lectures. Between-group differences...

  19. Aerobic and anaerobic biosynthesis of nano-selenium for remediation of mercury contaminated soil.

    Science.gov (United States)

    Wang, Xiaonan; Zhang, Daoyong; Pan, Xiangliang; Lee, Duu-Jong; Al-Misned, Fahad A; Mortuza, M Golam; Gadd, Geoffrey Michael

    2017-03-01

    Selenium (Se) nanoparticles are often synthesized by anaerobes. However, anaerobic bacteria cannot be directly applied for bioremediation of contaminated top soil which is generally aerobic. In this study, a selenite-reducing bacterium, Citrobacter freundii Y9, demonstrated high selenite reducing power and produced elemental nano-selenium nanoparticles (nano-Se 0 ) under both aerobic and anaerobic conditions. The biogenic nano-Se 0 converted 45.8-57.1% and 39.1-48.6% of elemental mercury (Hg 0 ) in the contaminated soil to insoluble mercuric selenide (HgSe) under anaerobic and aerobic conditions, respectively. Addition of sodium dodecyl sulfonate enhanced Hg 0 remediation, probably owing to the release of intracellular nano-Se 0 from the bacterial cells for Hg fixation. The reaction product after remediation was identified as non-reactive HgSe that was formed by amalgamation of nano-Se 0 and Hg 0 . Biosynthesis of nano-Se 0 both aerobically and anaerobically therefore provides a versatile and cost-effective remediation approach for Hg 0 -contaminated surface and subsurface soils, where the redox potential often changes dramatically. Copyright © 2016. Published by Elsevier Ltd.

  20. Effects of anaerobic digestion and aerobic treatment on gaseous emissions from dairy manure storages

    Science.gov (United States)

    Effects of anaerobic digestion and aerobic treatment on the reduction of gaseous emissions from dairy manure storages were evaluated in this study. Screened dairy manure containing 3.5% volatile solids (VS) was either anaerobically digested or aerobically treated prior to storage in air-tight vessel...

  1. Aerobic exercise effects upon cognition in Mild Cognitive Impairment: A systematic review of randomized controlled trials.

    Science.gov (United States)

    Cammisuli, D M; Innocenti, A; Franzoni, F; Pruneti, C

    2017-07-01

    Several studies have shown that physical activity has positive effects on cognition in healthy older adults without cognitive complains but lesser is known about the effectiveness of aerobic exercise in patients suffering from Mild Cognitive Impairment (MCI). The aim of the present study was to systematically review the evidence from randomized controlled trials (RCTs) about the effects of aerobic exercise upon cognition in MCI patients. To this end, PubMed, Cochrane and Web of Science databases were analytically searched for RCTs including aerobic exercise interventions for MCI patients. There is evidence that aerobic exercise improves cognition in MCI patients. Overall research reported moderate effects for global cognition, logical memory, inhibitory control and divided attention. Due to methodological limitations of the investigated studies, findings should be interpreted with caution. Standardized training protocols, larger scale interventions and follow-ups may also provide better insight into the preventive effects of aerobic exercise on cognitive deterioration in MCI and its conversion into dementia.

  2. Technology of wellness aerobics in the structure of personality-oriented program of physical rehabilitation of women with postmastectomy syndrome

    Directory of Open Access Journals (Sweden)

    Tatiana Odynets

    2015-10-01

    Full Text Available Purpose: to develop and substantiate technology of wellness aerobics in the structure of personality-oriented program of physical rehabilitation of women with postmastectomy syndrome on the dispensary stage of rehabilitation. Material and Methods: theoretical analysis and compilation of scientific and methodical literature and internet providers; induction and comparison. The study involved 115 women with postmastectomy syndrome on the dispensary stage of rehabilitation. Results: the developed program of wellness aerobics includes elements of basic aerobics, fitball aerobics, step-aerobics, strength training and stretching and their rational combination, which was implemented in accordance with the adaptation and training period of follow steps. Customization means of wellness aerobics depended on cardiorespiratory disorders, autonomic systems, limiting range of motion of the shoulder joint, degree of lymphostasis of women with postmastectomy syndrome

  3. Effekten av styrketräning kan begränsas mer av samtidig högintensiv intermittent aerob träning än av lågintensiv kontinuerlig aerob träning

    OpenAIRE

    Jutman, Magnus

    2012-01-01

    Introduktion Utifrån tidigare forskning har en modell föreslagits som beskriver att lågintensiv aerob uthållighetsträning ska ha mindre negativ påverkan på effekten av styrketräning jämfört med högintensiv aerob uthållighetsträning. Detta påstående har funnit visst stöd i litteraturen men vidare forskning krävs för att det ska kunna fastställas. Syfte Denna studie syftar till att undersöka ifall det föreligger någon skillnad mellan högintensiv aerob intermittent löpträning och lågintensiv aer...

  4. Anaerobe-Aerobe Submerged Biofilter Technology for Domestic Waste Water Treatment; Teknologi Biofilter Anaerob-Aerob Tercelup untuk Pengolahan Air Limbah Domestik

    Energy Technology Data Exchange (ETDEWEB)

    Nusa-Idaman-Said, [The Agency for the Assessment and Application of Technology, Jakarta (Indonesia)

    2000-02-15

    Water pollution in the big cities in Indonesia, especially in DKI Jakarta has shown serious problems. One of the potential sources of water pollution is domestic wastewater that is wastewater from kitchens, laundry, bathing and toilets. These problems have become more serious since the spreads of sewerage systems are still low, so that domestic, institutional and commercial wastewater cause severe water pollution in many rivers or shallow ground water. Bases on the fact that the progress of development of sewerage system is still low, it is important to develop low cost technology for individual house hold or semi communal wastewater treatment such as using anaerobic and aerobic submerged biofilter. This paper describes alternative technology for treatment of household wastewater or organic wastewater using anaerobic and aerobic submerged biofilter. Using this technology can decrease BOD, COD and Suspended Solids (SS) concentration more than 90 %. (author)

  5. Diagnosis Aerobic Component of Operational Preparedness Skill Players

    Directory of Open Access Journals (Sweden)

    Vasylyuk Vasyl

    2017-01-01

    Full Text Available Considerable importance for the control system, selection and orientation of the players on the stage long-term preparation plays a selection of effective methods of testing the various components of functional fitness athlete for timely, objective information about the players. The use of reliable scientific methods of effective monitoring of the athlete contributes to the further improvement of skills, increase athletic achievements. The purpose of this article is to describe and summarize modern methods of diagnosis and development of aerobic component of operational preparedness players qualifications. This article describes methods that actively and effectively used in leading European football teams. Specifically Yo-Yo test, test Shuttle (beep-test, Bangsbo test, test Hoff-Helgerud, test Conconi, Wingate-test. These tests have a high level of reliability and security mechanisms for assessing aerobic power players.

  6. Aerobic fitness relates to learning on a virtual morris water task and hippocampal volume in adolescents

    Science.gov (United States)

    Herting, Megan M.; Nagel, Bonnie J.

    2012-01-01

    In rodents, exercise increases hippocampal neurogenesis and allows for better learning and memory performance on water maze tasks. While exercise has also been shown to be beneficial for the brain and behavior in humans, no study has examined how exercise impacts spatial learning using a directly translational water maze task, or if these relationships exist during adolescence – a developmental period which the animal literature has shown to be especially vulnerable to exercise effects. In this study, we investigated the influence of aerobic fitness on hippocampal size and subsequent learning and memory, including visuospatial memory using a human analogue of the Morris Water Task, in 34 adolescents. Results showed that higher aerobic fitness predicted better learning on the virtual Morris Water Task and larger hippocampal volumes. No relationship between virtual Morris Water Task memory recall and aerobic fitness was detected. Aerobic fitness, however, did not relate to global brain volume, or verbal learning, which might suggest some specificity of the influence of aerobic fitness on the adolescent brain. This study provides a direct translational approach to the existing animal literature on exercise, as well as adds to the sparse research that exists on how aerobic exercise impacts the developing human brain and memory. PMID:22610054

  7. Aerobic fitness relates to learning on a virtual Morris Water Task and hippocampal volume in adolescents.

    Science.gov (United States)

    Herting, Megan M; Nagel, Bonnie J

    2012-08-01

    In rodents, exercise increases hippocampal neurogenesis and allows for better learning and memory performance on water maze tasks. While exercise has also been shown to be beneficial for the brain and behavior in humans, no study has examined how exercise impacts spatial learning using a directly translational water maze task, or if these relationships exist during adolescence--a developmental period which the animal literature has shown to be especially vulnerable to exercise effects. In this study, we investigated the influence of aerobic fitness on hippocampal size and subsequent learning and memory, including visuospatial memory using a human analogue of the Morris Water Task, in 34 adolescents. Results showed that higher aerobic fitness predicted better learning on the virtual Morris Water Task and larger hippocampal volumes. No relationship between virtual Morris Water Task memory recall and aerobic fitness was detected. Aerobic fitness, however, did not relate to global brain volume or verbal learning, which might suggest some specificity of the influence of aerobic fitness on the adolescent brain. This study provides a direct translational approach to the existing animal literature on exercise, as well as adds to the sparse research that exists on how aerobic exercise impacts the developing human brain and memory. Published by Elsevier B.V.

  8. Aerobic granular SBR systems applied to the treatment of industrial effluents

    International Nuclear Information System (INIS)

    Rio, V. del; Figueroa, M.; Arrojo, B.; Mosquera-Corral, A.; Campos, J. L.; Garcia-Torriello, G.; Mendez, R.

    2009-01-01

    Systems based on aerobic granular biomass are an alternative to the conventional activated sludge plants for wastewater treatment. Large organic and nitrogen loads are treated in these systems where biomass grown as granules, easy to separate by setting, make unnecessary the construction of secondary settler reducing the surface requirements for the treatment system construction. Furthermore, in aerobic granular reactors simultaneously carbon and nitrogen removal is feasible. These systems have been already applied at laboratory scale for the treatment of different types of industrial and urban wastewater. (Author)

  9. Aerobic granular SBR systems applied to the treatment of industrial effluents

    Energy Technology Data Exchange (ETDEWEB)

    Rio, V. del; Figueroa, M.; Arrojo, B.; Mosquera-Corral, A.; Campos, J. L.; Garcia-Torriello, G.; Mendez, R.

    2009-07-01

    Systems based on aerobic granular biomass are an alternative to the conventional activated sludge plants for wastewater treatment. Large organic and nitrogen loads are treated in these systems where biomass grown as granules, easy to separate by setting, make unnecessary the construction of secondary settler reducing the surface requirements for the treatment system construction. Furthermore, in aerobic granular reactors simultaneously carbon and nitrogen removal is feasible. These systems have been already applied at laboratory scale for the treatment of different types of industrial and urban wastewater. (Author)

  10. Aerobic glycolysis during brain activation: adrenergic regulation and influence of norepinephrine on astrocytic metabolism.

    Science.gov (United States)

    Dienel, Gerald A; Cruz, Nancy F

    2016-07-01

    Aerobic glycolysis occurs during brain activation and is characterized by preferential up-regulation of glucose utilization compared with oxygen consumption even though oxygen level and delivery are adequate. Aerobic glycolysis is a widespread phenomenon that underlies energetics of diverse brain activities, such as alerting, sensory processing, cognition, memory, and pathophysiological conditions, but specific cellular functions fulfilled by aerobic glycolysis are poorly understood. Evaluation of evidence derived from different disciplines reveals that aerobic glycolysis is a complex, regulated phenomenon that is prevented by propranolol, a non-specific β-adrenoceptor antagonist. The metabolic pathways that contribute to excess utilization of glucose compared with oxygen include glycolysis, the pentose phosphate shunt pathway, the malate-aspartate shuttle, and astrocytic glycogen turnover. Increased lactate production by unidentified cells, and lactate dispersal from activated cells and lactate release from the brain, both facilitated by astrocytes, are major factors underlying aerobic glycolysis in subjects with low blood lactate levels. Astrocyte-neuron lactate shuttling with local oxidation is minor. Blockade of aerobic glycolysis by propranolol implicates adrenergic regulatory processes including adrenal release of epinephrine, signaling to brain via the vagus nerve, and increased norepinephrine release from the locus coeruleus. Norepinephrine has a powerful influence on astrocytic metabolism and glycogen turnover that can stimulate carbohydrate utilization more than oxygen consumption, whereas β-receptor blockade 're-balances' the stoichiometry of oxygen-glucose or -carbohydrate metabolism by suppressing glucose and glycogen utilization more than oxygen consumption. This conceptual framework may be helpful for design of future studies to elucidate functional roles of preferential non-oxidative glucose utilization and glycogen turnover during brain

  11. The association between aerobic fitness and physical activity in children and adolescents

    DEFF Research Database (Denmark)

    Kristensen, Peter Lund; Moeller, Niels Christian; Korsholm, Lars

    2010-01-01

    of physical activity. This study investigated the cross-sectional and longitudinal relationship between aerobic fitness and physical activity in a representative sample of 9 and 15-year-old children (n = 1260 cross-sectional, n = 153 longitudinal). The specific goal was to improve past studies using...... an objective method of activity assessment and taking into account a number of major sources of error. Data came from the Danish part of the European youth heart study, 1997-2003. The cross-sectional results generally showed a weak to moderate association between aerobic fitness and physical activity......The link between aerobic fitness and physical activity in children has been studied in a number of earlier studies and the results have generally shown weak to moderate correlations. This overall finding has been widely questioned partly because of the difficulty in obtaining valid estimates...

  12. Aerobic treatment of swine manure to enhance anaerobic digestion and microalgal cultivation.

    Science.gov (United States)

    Bekoe, Dominic; Wang, Lijun; Zhang, Bo; Scott Todd, Matthew; Shahbazi, Abolghasem

    2018-02-01

    Aerobic treatment of swine manure was coupled with anaerobic digestion and microalgal cultivation. A 14-day aerobic treatment reduced the total solid content of swine manure by >15%. Ammonia and carbon dioxide were stripped by the air supplied, and this off-gas was further used to aerate the culture of Chlorella vulgaris. The microalgal growth rates in Bristol medium and the wastewater with the off-gas increased from 0.08 to 0.22 g/L/d and from 0.15 to 0.24 g/L/d, respectively. Meanwhile, the aerobically treated swine manure showed a higher methane yield during anaerobic digestion. The experimental results were used to establish a demonstration unit consisting of a 100 L composter, a 200 L anaerobic digester, a 60 L tubular photobioreactor, and a 300 L micro-open raceway pond.

  13. Associations of Adiposity and Aerobic Fitness with Executive Function and Math Performance in Danish Adolescents.

    Science.gov (United States)

    Huang, Tao; Tarp, Jakob; Domazet, Sidsel Louise; Thorsen, Anne Kær; Froberg, Karsten; Andersen, Lars Bo; Bugge, Anna

    2015-10-01

    To examine the associations of adiposity and aerobic fitness with executive function and math performance in Danish adolescents. Cross-sectional analyses were conducted with data on 525 adolescents attending sixth and seventh grades from 14 schools in the 5 main regions of Denmark. A modified Eriksen flanker task was used to assess inhibitory control, a key aspect of executive function. Academic performance was assessed by a customized math test. Aerobic fitness was assessed by an intermittent shuttle-run test (Andersen test). Body mass index (BMI) was negatively associated with accuracy on incongruent trials during the flanker task (P = .005). A higher BMI was associated with a larger accuracy interference score (P = .01). Similarly, waist circumference (WC) was negatively associated with accuracy on incongruent trials (P = .008). A higher WC was associated with a larger reaction time (RT) interference score (P = .02) and accuracy interference score (P = .009). Higher aerobic fitness was associated with a faster RT on congruent trials (P = .009) and incongruent trials (P = .003). Higher aerobic fitness was associated with a smaller RT interference score (P = .04). Aerobic fitness was positively associated with math score (P math score (P > .05). These results suggest that aerobic fitness is positively associated with both inhibitory control and math performance in adolescents. Adiposity is negatively associated with inhibitory control in adolescents. Adiposity is not associated with math performance. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Beneficial mechanisms of aerobic exercise on hepatic lipid metabolism in non-alcoholic fatty liver disease.

    Science.gov (United States)

    Guo, Rui; Liong, Emily C; So, Kwok Fai; Fung, Man-Lung; Tipoe, George L

    2015-04-01

    Non-alcoholic fatty liver disease (NAFLD) refers to any fatty liver disease that is not due to excessive use of alcohol. NAFLD probably results from abnormal hepatic lipid metabolism and insulin resistance. Aerobic exercise is shown to improve NAFLD. This review aimed to evaluate the molecular mechanisms involved in the beneficial effects of aerobic exercise on NAFLD. We searched articles in English on the role of aerobic exercise in NAFLD therapy in PubMed. The mechanisms of chronic aerobic exercise in regulating the outcome of NAFLD include: (i) reducing intrahepatic fat content by down-regulating sterol regulatory element-binding protein-1c and up-regulating peroxisome proliferator-activated receptor gamma expression levels; (ii) decreasing hepatic oxidative stress through modulating the reactive oxygen species, and enhancing antioxidant enzymes such as catalase and glutathione peroxidase; (iii) ameliorating hepatic inflammation via the inhibition of pro-inflammatory mediators such as tumor necrosis factor-alpha and interleukin-1 beta; (iv) attenuating mitochondrial dependent apoptosis by reducing cytochrome C released from the mitochondria to the cytosol; and (v) inducing hepato-protective autophagy. Aerobic exercise, via different mechanisms, significantly decreases the fat content of the liver and improves the outcomes of patients with NAFLD.

  15. Validity of Submaximal Cycle Ergometry for Estimating Aerobic Capacity

    National Research Council Canada - National Science Library

    Myhre, Loren

    1998-01-01

    ... that allows early selection of the most appropriate test work load. A computerized version makes it possible for non-trained personnel to safely administer this test for estimating aerobic capacity...

  16. Sialidase activity in aerobic vaginitis is equal to levels during bacterial vaginosis

    OpenAIRE

    Marconi, C.; Donders, G.G.G.; Bellen, G.; Brown, D.R.; Parada, C.M.G.L.; Silva, M.G.

    2013-01-01

    Objective: To evaluate levels of proinflammatory cytokines and sialidase activity in aerobic vaginitis (AV) in relation to normal vaginal flora and bacterial vaginosis (BV). Study design: In this cross-sectional study, a total of 682 consecutive non-pregnant women attending the gynecology service were assessed and 408 women were included. Vaginal rinsing samples were collected from 223 women with microscopic finding of BV (n = 98), aerobic vaginitis (n = 25) and normal flora (n = 100). Sample...

  17. Six weeks' aerobic retraining after two weeks' immobilization restores leg lean mass and aerobic capacity but does not fully rehabilitate leg strenght in young and older men

    DEFF Research Database (Denmark)

    Vigelsø Hansen, Andreas; Gram, Martin; Wiuff, Caroline

    2015-01-01

    OBJECTIVE: To determine the effect of aerobic retraining as rehabilitation after short-term leg immobilization on leg strength, leg work capacity, leg lean mass, leg muscle fibre type composition and leg capillary supply, in young and older men. SUBJECTS AND DESIGN: Seventeen young (23 ± 1 years...... immobilization had marked effects on leg strength, and work capacity and 6 weeks' retraining was sufficient to increase, but not completely rehabilitate, muscle strength, and to rehabilitate aerobic work capacity and leg lean mass (in the young men)....

  18. ASSESSING AEROBIC NATURAL ATTENUATION OF TRICHLOROETHENE AT FOUR DOE SITES

    International Nuclear Information System (INIS)

    Koelsch, Michael C.; Starr, Robert C.; Sorenson, Kent S. Jr.

    2005-01-01

    A 3-year Department of Energy Environmental Science Management Program (EMSP) project is currently investigating natural attenuation of trichloroethane (TCE) in aerobic groundwater. This presentation summarizes the results of a screening process to identify TCE plumes at DOE facilities that are suitable for assessing the rate of TCE cometabolism under aerobic conditions. In order to estimate aerobic degradation rates, plumes had to meet the following criteria: TCE must be present in aerobic groundwater, a conservative co-contaminant must be present and have approximately the same source as TCE, and the groundwater velocity must be known. A total of 127 TCE plumes were considered across 24 DOE sites. The four sites retained for the assessment were: (1) Brookhaven National Laboratory, OU III; (2) Paducah Gaseous Diffusion Plant, Northwest Plume; (3) Rocky Flats Environmental Technology Site, Industrialized Area--Southwest Plume and 903 Pad South Plume; and (4) Savannah River Site, A/M Area Plume. For each of these sites, a co-contaminant derived from the same source area as TCE was used as a nonbiodegrading tracer. The tracer determined the extent to which concentration decreases in the plume can be accounted for solely by abiotic processes such as dispersion and dilution. Any concentration decreases not accounted for by these processes must be explained by some other natural attenuation mechanism. Thus, ''half-lives'' presented herein are in addition to attenuation that occurs due to hydrologic mechanisms. This ''tracer-corrected method'' has previously been used at the DOE's Idaho National Engineering and Environmental Laboratory in conjunction with other techniques to document the occurrence of intrinsic aerobic cometabolism. Application of this method to other DOE sites is the first step to determining whether this might be a significant natural attenuation mechanism on a broader scale. Application of the tracer-corrected method to data from the Brookhaven

  19. Preventing Cardiovascular Disease Risk Factors through Aerobic ...

    African Journals Online (AJOL)

    This paper focused on the reduction of cardiovascular disease risk factors, through aerobic exercises. The central argument here is that through exercise there is the tendency for increased strength of the heart muscles. When this is the case, what follows is a reduction in body weight and ultimately less risk on the ...

  20. Acute exercise and aerobic fitness influence selective attention during visual search

    Science.gov (United States)

    Bullock, Tom; Giesbrecht, Barry

    2014-01-01

    Successful goal directed behavior relies on a human attention system that is flexible and able to adapt to different conditions of physiological stress. However, the effects of physical activity on multiple aspects of selective attention and whether these effects are mediated by aerobic capacity, remains unclear. The aim of the present study was to investigate the effects of a prolonged bout of physical activity on visual search performance and perceptual distraction. Two groups of participants completed a hybrid visual search flanker/response competition task in an initial baseline session and then at 17-min intervals over a 2 h 16 min test period. Participants assigned to the exercise group engaged in steady-state aerobic exercise between completing blocks of the visual task, whereas participants assigned to the control group rested in between blocks. The key result was a correlation between individual differences in aerobic capacity and visual search performance, such that those individuals that were more fit performed the search task more quickly. Critically, this relationship only emerged in the exercise group after the physical activity had begun. The relationship was not present in either group at baseline and never emerged in the control group during the test period, suggesting that under these task demands, aerobic capacity may be an important determinant of visual search performance under physical stress. The results enhance current understanding about the relationship between exercise and cognition, and also inform current models of selective attention. PMID:25426094