WorldWideScience

Sample records for oceanic n2-fixing microorganism

  1. The complex effects of ocean acidification on the prominent N2-fixing cyanobacterium Trichodesmium.

    Science.gov (United States)

    Hong, Haizheng; Shen, Rong; Zhang, Futing; Wen, Zuozhu; Chang, Siwei; Lin, Wenfang; Kranz, Sven A; Luo, Ya-Wei; Kao, Shuh-Ji; Morel, François M M; Shi, Dalin

    2017-05-05

    Acidification of seawater caused by anthropogenic carbon dioxide (CO 2 ) is anticipated to influence the growth of dinitrogen (N 2 )-fixing phytoplankton, which contribute a large fraction of primary production in the tropical and subtropical ocean. We found that growth and N 2 -fixation of the ubiquitous cyanobacterium Trichodesmium decreased under acidified conditions, notwithstanding a beneficial effect of high CO 2 Acidification resulted in low cytosolic pH and reduced N 2 -fixation rates despite elevated nitrogenase concentrations. Low cytosolic pH required increased proton pumping across the thylakoid membrane and elevated adenosine triphosphate production. These requirements were not satisfied under field or experimental iron-limiting conditions, which greatly amplified the negative effect of acidification. Copyright © 2017, American Association for the Advancement of Science.

  2. Effect of systemic herbicides on N2-fixing and phosphate solubilizing microorganisms in relation to availability of nitrogen and phosphorus in paddy soils of West Bengal.

    Science.gov (United States)

    Das, Amal Chandra; Debnath, Anjan

    2006-11-01

    A field experiment has been conducted with four systemic herbicides viz., butachlor [N-(butoxymethyl)-2-chloro-2',6'-diethyl-acetanilide], fluchloralin [N-(2-chloroethyl)-(2,6-dinitro-N-propyl-4-trifluoromethyl) aniline], oxadiazon [5-terbutyl-3-(2,4-dichloro-5-isopro poxyphenyl)-1,3,4-oxadiazol-2-one] and oxyfluorfen [2-chloro-1-(3-ethoxy-4-nitrophenyl)-4-(trifluoromethyl) benzene] at their recommended field rates (2.0, 1.5, 0.4 and 0.12kga.i.ha(-1), respectively) to investigate their effects on growth and activities of aerobic non-symbiotic N(2)-fixing bacteria and phosphate solubilizing microorganisms in relation to availability of nitrogen and phosphorus in the rhizosphere soils as well as yield of the rice crop (Oryza sativa L cv. IR-36). Application of herbicides, in general, highly stimulated the population and activities of the target microorganisms, which resulted in a greater amount of atmospheric nitrogen fixation and phosphate solubilization in the rhizosphere soils of the test crop. The greater microbial activities subsequently augmented the mineralization and availability of nitrogen and phosphorus in the soil solution, which in turn increased the yield of the crop. Among the herbicides, oxyfluorfen was most stimulative followed by fluchloralin and oxadiazon in augmenting the microbial activities in soil. Butachlor also accentuated the mineralization and availability of nitrogen due to higher incitement of non-symbiotic N(2)-fixing bacteria in paddy soil. The grain and straw yields of the crop were also significantly increased due to the application of oxyfluorfen (20.2% and 21%) followed by fluchloralin (13.1% and 15.4%) and butachlor (9.1% and 10.2%), respectively.

  3. Quantification of Atmospheric N2 Fixed by Cowpea, Pigeonpea and ...

    African Journals Online (AJOL)

    at taking advantage of legumes to replenish soil nitrogen (N due to legumes' N2 fixation). Glasshouse pot ... In both cases, maize (Katumani variety) was the non- N2- fixing reference crop. ... Biological N2 fixation is affected by several factors,.

  4. N2-fixing red alder indirectly accelerates ecosystem nitrogen cycling

    Science.gov (United States)

    Perakis, Steven S.; Matkins, Joselin J.; Hibbs, David E.

    2012-01-01

    Symbiotic N2-fixing tree species can accelerate ecosystem N dynamics through decomposition via direct pathways by producing readily decomposed leaf litter and increasing N supply to decomposers, as well as via indirect pathways by increasing tissue and detrital N in non-fixing vegetation. To evaluate the relative importance of these pathways, we compared three-year decomposition and N dynamics of N2-fixing red alder leaf litter (2.34 %N) to both low-N (0.68 %N) and high-N (1.21 %N) litter of non-fixing Douglas-fir, and decomposed each litter source in four forests dominated by either red alder or Douglas-fir. We also used experimental N fertilization of decomposition plots to assess elevated N availability as a potential mechanism of N2-fixer effects on litter mass loss and N dynamics. Direct effects of N2-fixing red alder on decomposition occurred primarily as faster N release from red alder than Douglas-fir litter, but direct increases in N supply to decomposers via fertilization did not stimulate decomposition of any litter. Fixed N indirectly influenced detrital dynamics by increasing Douglas-fir tissue and litter N concentrations, which accelerated litter N release without accelerating mass loss. By increasing soil N, tissue N, and the rate of N release from litter of non-fixers, we conclude that N2-fixing vegetation can indirectly foster plant-soil feedbacks that contribute to the persistence of elevated N availability in terrestrial ecosystems.

  5. Controlling cyanobacterial blooms in hypertrophic Lake Taihu, China: will nitrogen reductions cause replacement of non-N2 fixing by N2 fixing taxa?

    Directory of Open Access Journals (Sweden)

    Hans W Paerl

    Full Text Available Excessive anthropogenic nitrogen (N and phosphorus (P inputs have caused an alarming increase in harmful cyanobacterial blooms, threatening sustainability of lakes and reservoirs worldwide. Hypertrophic Lake Taihu, China's third largest freshwater lake, typifies this predicament, with toxic blooms of the non-N2 fixing cyanobacteria Microcystis spp. dominating from spring through fall. Previous studies indicate N and P reductions are needed to reduce bloom magnitude and duration. However, N reductions may encourage replacement of non-N2 fixing with N2 fixing cyanobacteria. This potentially counterproductive scenario was evaluated using replicate, large (1000 L, in-lake mesocosms during summer bloom periods. N+P additions led to maximum phytoplankton production. Phosphorus enrichment, which promoted N limitation, resulted in increases in N2 fixing taxa (Anabaena spp., but it did not lead to significant replacement of non-N2 fixing with N2 fixing cyanobacteria, and N2 fixation rates remained ecologically insignificant. Furthermore, P enrichment failed to increase phytoplankton production relative to controls, indicating that N was the most limiting nutrient throughout this period. We propose that Microcystis spp. and other non-N2 fixing genera can maintain dominance in this shallow, highly turbid, nutrient-enriched lake by outcompeting N2 fixing taxa for existing sources of N and P stored and cycled in the lake. To bring Taihu and other hypertrophic systems below the bloom threshold, both N and P reductions will be needed until the legacy of high N and P loading and sediment nutrient storage in these systems is depleted. At that point, a more exclusive focus on P reductions may be feasible.

  6. Aerobic and anaerobic nitrogen transformation processes in N2-fixing cyanobacterial aggregates.

    Science.gov (United States)

    Klawonn, Isabell; Bonaglia, Stefano; Brüchert, Volker; Ploug, Helle

    2015-06-01

    Colonies of N(2)-fixing cyanobacteria are key players in supplying new nitrogen to the ocean, but the biological fate of this fixed nitrogen remains poorly constrained. Here, we report on aerobic and anaerobic microbial nitrogen transformation processes that co-occur within millimetre-sized cyanobacterial aggregates (Nodularia spumigena) collected in aerated surface waters in the Baltic Sea. Microelectrode profiles showed steep oxygen gradients inside the aggregates and the potential for nitrous oxide production in the aggregates' anoxic centres. (15)N-isotope labelling experiments and nutrient analyses revealed that N(2) fixation, ammonification, nitrification, nitrate reduction to ammonium, denitrification and possibly anaerobic ammonium oxidation (anammox) can co-occur within these consortia. Thus, N. spumigena aggregates are potential sites of nitrogen gain, recycling and loss. Rates of nitrate reduction to ammonium and N(2) were limited by low internal nitrification rates and low concentrations of nitrate in the ambient water. Presumably, patterns of N-transformation processes similar to those observed in this study arise also in other phytoplankton colonies, marine snow and fecal pellets. Anoxic microniches, as a pre-condition for anaerobic nitrogen transformations, may occur within large aggregates (⩾1 mm) even when suspended in fully oxygenated waters, whereas anoxia in small aggregates (1.5 μM), O(2)-depleted water layers, for example, in the chemocline of the Baltic Sea or the oceanic mesopelagic zone, aggregates may promote N-recycling and -loss processes.

  7. Ocean acidification and marine microorganisms: responses and consequences

    Directory of Open Access Journals (Sweden)

    Surajit Das

    2015-10-01

    Full Text Available Ocean acidification (OA is one of the global issues caused by rising atmospheric CO2. The rising pCO2 and resulting pH decrease has altered ocean carbonate chemistry. Microbes are key components of marine environments involved in nutrient cycles and carbon flow in marine ecosystems. However, these marine microbes and the microbial processes are sensitive to ocean pH shift. Thus, OA affects the microbial diversity, primary productivity and trace gases emission in oceans. Apart from that, it can also manipulate the microbial activities such as quorum sensing, extracellular enzyme activity and nitrogen cycling. Short-term laboratory experiments, mesocosm studies and changing marine diversity scenarios have illustrated undesirable effects of OA on marine microorganisms and ecosystems. However, from the microbial perspective, the current understanding on effect of OA is based mainly on limited experimental studies. It is challenging to predict response of marine microbes based on such experiments for this complex process. To study the response of marine microbes towards OA, multiple approaches should be implemented by using functional genomics, new generation microscopy, small-scale interaction among organisms and/or between organic matter and organisms. This review focuses on the response of marine microorganisms to OA and the experimental approaches to investigate the effect of changing ocean carbonate chemistry on microbial mediated processes.

  8. Ecological consequences of the expansion of N2-fixing plants in cold biomes

    Science.gov (United States)

    Hiltbrunner, Erika; Aerts, Rien; Bühlmann, Tobias; Huss-Danell, Kerstin; Magnusson, Borgthor; Myrold, David D.; Reed, Sasha C.; Sigurdsson, Bjarni D.; Körner, Christian

    2014-01-01

    Research in warm-climate biomes has shown that invasion by symbiotic dinitrogen (N2)-fixing plants can transform ecosystems in ways analogous to the transformations observed as a consequence of anthropogenic, atmospheric nitrogen (N) deposition: declines in biodiversity, soil acidification, and alterations to carbon and nutrient cycling, including increased N losses through nitrate leaching and emissions of the powerful greenhouse gas nitrous oxide (N2O). Here, we used literature review and case study approaches to assess the evidence for similar transformations in cold-climate ecosystems of the boreal, subarctic and upper montane-temperate life zones. Our assessment focuses on the plant genera Lupinus and Alnus, which have become invasive largely as a consequence of deliberate introductions and/or reduced land management. These cold biomes are commonly located in remote areas with low anthropogenic N inputs, and the environmental impacts of N2-fixer invasion appear to be as severe as those from anthropogenic N deposition in highly N polluted areas. Hence, inputs of N from N2 fixation can affect ecosystems as dramatically or even more strongly than N inputs from atmospheric deposition, and biomes in cold climates represent no exception with regard to the risk of being invaded by N2-fixing species. In particular, the cold biomes studied here show both a strong potential to be transformed by N2-fixing plants and a rapid subsequent saturation in the ecosystem’s capacity to retain N. Therefore, analogous to increases in N deposition, N2-fixing plant invasions must be deemed significant threats to biodiversity and to environmental quality.

  9. N2-fixing legumes are linked to enhanced mineral dissolution and microbiome modulations in Neotropical rainforests

    Science.gov (United States)

    Epihov, Dimitar; Batterman, Sarah; Hedin, Lars; Saltonstall, Kristin; Hall, Jefferson; Leake, Jonathan; Beerling, David

    2017-04-01

    Legumes represent the dominant family of many tropical forests with estimates of 120 billion legume trees in the Amazon basin alone. Many rainforest legume trees form symbioses with N2-fixing bacteria. In the process of atmospheric N2-fixation large amounts of nitrogen-rich litter are generated, supplying half of all nitrogen required to support secondary rainforest succession. However, it is unclear how N2-fixers affect the biogeochemical cycling of other essential nutrients by affecting the rates of mineral dissolution and rock weathering. Here we show that N2-fixing legumes in young Panamanian rainforests promote acidification and enhance silicate rock weathering by a factor of 2 compared to non-fixing trees. We report that N2-fixers also associate with enhanced dissolution of Al- and Fe-bearing secondary minerals native to tropical oxisols. In legume-rich neighbourhoods, non-fixers benefited from raised weathering rates relative to those of legume-free zones thus suggesting a positive community effect driven by N2-fixers. These changes in weathering potential were tracked by parallel functional and structural changes in the soil and rock microbiomes. Our findings support the view that N2-fixing legumes are central components of biogeochemical cycling, associated with enhanced release of Fe- and Al-bound P and primary mineral products (Mg, Mo). Rainforest legume services therefore bear important implications to short-term C cycling related to forest growth and the long-term C cycle related to marine carbonate deposition fuelled by silicate weathering.

  10. Natural isotopes abundance of 15N and 13C in leaves of some N2-fixing and non N2-fixing trees and shrubs in Syria

    International Nuclear Information System (INIS)

    Kurdali, F.; Al-Shamma'a, M.

    2007-12-01

    Variability in the natural abundance isotopes of 15 N and 13 C in leaves of several legume and non-legume plant species grown at different sites of two areas in semi-arid regions of Syria was determined. In the first area (non-saline soil), the 15 N values of a number of fixing and non-fixing reference plants ranged from -2.09 to +9.46, depending on plant species and studied site. 15 N in a number of legume species including Acacia cyanopylla (-1.73), Acacia farnesiana (-0.55), Prosopis juliflora (-1.64) and Medicago arborea (+1.6) were close to the atmospheric value pointing to a major contribution of N 2 fixing in these species; whereas, those of reference plants were highly positive (between +3.6 and +9.46%). In the actinorhizal tree, Elaeagnus angustifolia, the 15 N abundance was far lower (-0.46 to -2.1%) strongly suggesting that the plant obtained large proportional contribution from BNF. In contrast, δ 15 N values in some other legumes and actinorhizal plants were relatively similar to those of reference plants, suggesting that the contribution of fixed N 2 is negligible. On the other hand, δ 13 C% values in leaves of C3 plants were affected by plant species, ranging from a minimum of -28.67% to a maximum of -23%. However, they were the same within each plant species although they were grown at different sites. Moreover, dual stable isotope analysis in leaves of Prosopis juliflora and other non- legumes grown on a salt affected soil (second area) was also conducted. Results showed that salinity did not affect C assimilation in this woody legume since a higher carbon discrimination was obtained indicating that this plant is a salt tolerant species; whereas, N2-fixation was drastically affected (δ 15 N= +7.03). (Author)

  11. Natural abundances of 15N and 13C in leaves of some N2-fixing and non-N2-fixing trees and shrubs in Syria.

    Science.gov (United States)

    Kurdali, F; Al-Shamma'a, M

    2009-09-01

    A survey study was conducted on man-made plantations located at two different areas in the arid region of Syria to determine the variations in natural abundances of the (15)N and (13)C isotopes in leaves of several woody legume and non-legume species, and to better understand the consequence of such variations on nitrogen fixation and carbon assimilation. In the first study area (non-saline soil), the delta(15)N values in four legume species (Acacia cyanophylla,-1.73 per thousand Acacia farnesiana,-0.55 per thousand Prosopis juliflora,-1.64 per thousand; and Medicago arborea,+1.6 \\textperthousand) and one actinorhizal plant (Elaeagnus angustifolia,-0.46 to-2.1 per thousand) were found to be close to that of the atmospheric value pointing to a major contribution of N(2) fixing in these species; whereas, delta(15)N values of the non-fixing plant species were highly positive. delta(13)C per thousand; in leaves of the C3 plants were found to be affected by plant species, ranging from a minimum of-28.67 per thousand; to a maximum of-23 per thousand. However, they were relatively similar within each plant species although they were grown at different sites. In the second study area (salt affected soil), a higher carbon discrimination value (Delta(13)C per thousand) was exhibited by P. juliflora, indicating that the latter is a salt tolerant species; however, its delta(15)N was highly positive (+7.03 per thousand) suggesting a negligible contribution of the fixed N(2). Hence, it was concluded that the enhancement of N(2) fixation might be achieved by selection of salt-tolerant Rhizobium strains.

  12. Natural abundances of 15N and 13C in leaves of some N2- fixing and non N2- fixing trees and shrubs in Syria

    International Nuclear Information System (INIS)

    Kurdali, F.; Al-Shamma'a, M.

    2010-01-01

    A survey study was conducted on man-made plantations located at two different areas in the arid region of Syria to determine the variations in natural abundances of the 12 N and 13 C isotopes in leaves of several woody legume and non-legume species, and to better understand the consequence of such variations on nitrogen fixation and carbon assimilation. In the first study area (non-saline soil), the δ 15 N values in four legume species (Acacia cyanopylla, -1.73 %; Acacia farnesiana, -0.55%; Prosopis juliflora, -1.64%, and Medicago arborea, +1.6%) and one actinorhizal plant (Elaeagnus angustifolia, -0.46 to -2.1%) were found to be close to that of the atmospheric value pointing to a major contribution of N 2 fixing in these species; whereas, δ 15 N values of the non-fixing plant species were highly positive.δ 13 C% in leaves of the C 3 plants were found to be affected by plant species, ranging from a minimum of -28.67% to a maximum of -23%. However, they were relatively similar within each plant species although they were grown at different sites. In the second study area (salt affected soil) a higher carbon discrimination value (Δ 3 C%) was exhibited by Prosopis juliflora indicating that the latter is a salt tolerant species; however, its δ 15 N was highly positive (+7.03%) suggesting a negligible contribution of the fixed N 2 . Hence, it was concluded that the enhancement of N 2 fixation might be achieved by selection of salt-tolerant rhizobium strains. (author)

  13. The Biology of Heterotrophic N2-fixing Bacteria in Marine and Estuarine Waters

    DEFF Research Database (Denmark)

    Bentzon-Tilia, Mikkel

    Biological nitrogen (N)2 fixation is of paramount importance for marine N cycling and for life in the oceans in general. It represents the sole mechanism by which microorganisms can channel inert atmospheric N2 gas into biomass and hence it may fuel a significant fraction of primary production...... heterotrophic isolates, this thesis aims at addressing these unknowns. It was found that heterotrophic diazotrophs were present and active in environments previously not associated with N2 fixation e.g. suboxic basins of the Baltic Sea and estuarine surface waters. In these environments they contributed...... with significant amounts fixed N2, suggesting that a reevaluation of the significance of N fixation in suboxic waters and estuarine coastal waters is warranted. It was also documented that heterotrophic diazotrophs could be enriched in culture based on their ability to utilize N2 as the sole N source...

  14. Biogeographic partitioning of Southern Ocean microorganisms revealed by metagenomics.

    Science.gov (United States)

    Wilkins, David; Lauro, Federico M; Williams, Timothy J; Demaere, Matthew Z; Brown, Mark V; Hoffman, Jeffrey M; Andrews-Pfannkoch, Cynthia; McQuaid, Jeffrey B; Riddle, Martin J; Rintoul, Stephen R; Cavicchioli, Ricardo

    2013-05-01

    We performed a metagenomic survey (6.6 Gbp of 454 sequence data) of Southern Ocean (SO) microorganisms during the austral summer of 2007-2008, examining the genomic signatures of communities across a latitudinal transect from Hobart (44°S) to the Mertz Glacier, Antarctica (67°S). Operational taxonomic units (OTUs) of the SAR11 and SAR116 clades and the cyanobacterial genera Prochlorococcus and Synechococcus were strongly overrepresented north of the Polar Front (PF). Conversely, OTUs of the Gammaproteobacterial Sulfur Oxidizer-EOSA-1 (GSO-EOSA-1) complex, the phyla Bacteroidetes and Verrucomicrobia and order Rhodobacterales were characteristic of waters south of the PF. Functions enriched south of the PF included a range of transporters, sulfur reduction and histidine degradation to glutamate, while branched-chain amino acid transport, nucleic acid biosynthesis and methionine salvage were overrepresented north of the PF. The taxonomic and functional characteristics suggested a shift of primary production from cyanobacteria in the north to eukaryotic phytoplankton in the south, and reflected the different trophic statuses of the two regions. The study provides a new level of understanding about SO microbial communities, describing the contrasting taxonomic and functional characteristics of microbial assemblages either side of the PF. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  15. Soil recovery after removal of the N2-fixing invasive Acacia longifolia: consequences for ecosystem restoration

    DEFF Research Database (Denmark)

    Marchante, Elizabete; Kjøller, Annelise Helene; Struwe, Sten

    2009-01-01

    Invasion by Acacia longifolia alters soil characteristics and processes. The present study was conducted to determine if the changes in soil C and N pools and processes induced by A. longifolia persist after its removal, at the São Jacinto Dunes Nature Reserve (Portugal). Some areas had been...... invaded for a long time (>20 years) and others more recently (Soil samples...... decrease (>54% and >95%, respectively) after removal of both A. longifolia and litter. Our results suggest that after removal of an N2-fixing invasive tree that changes ecosystem-level processes, it takes several years before soil nutrients and processes return to pre-invasion levels, but this legacy...

  16. N2-fixing tropical legume evolution: a contributor to enhanced weathering through the Cenozoic?

    Science.gov (United States)

    Epihov, Dimitar Z; Batterman, Sarah A; Hedin, Lars O; Leake, Jonathan R; Smith, Lisa M; Beerling, David J

    2017-08-16

    Fossil and phylogenetic evidence indicates legume-rich modern tropical forests replaced Late Cretaceous palm-dominated tropical forests across four continents during the early Cenozoic (58-42 Ma). Tropical legume trees can transform ecosystems via their ability to fix dinitrogen (N 2 ) and higher leaf N compared with non-legumes (35-65%), but it is unclear how their evolutionary rise contributed to silicate weathering, the long-term sink for atmospheric carbon dioxide (CO 2 ). Here we hypothesize that the increasing abundance of N 2 -fixing legumes in tropical forests amplified silicate weathering rates by increased input of fixed nitrogen (N) to terrestrial ecosystems via interrelated mechanisms including increasing microbial respiration and soil acidification, and stimulating forest net primary productivity. We suggest the high CO 2 early Cenozoic atmosphere further amplified legume weathering. Evolution of legumes with high weathering rates was probably driven by their high demand for phosphorus and micronutrients required for N 2 -fixation and nodule formation. © 2017 The Author(s).

  17. Turbulence from a microorganism's perspective: Does the open ocean feel different than a coral reef?

    Science.gov (United States)

    Pepper, Rachel; Variano, Evan; Koehl, M. A. R.

    2012-11-01

    Microorganisms in the ocean live in turbulent flows. Swimming microorganisms navigate through the water (e.g. larvae land on suitable substrata, predators find patches of prey), but the mechanisms by which they do so in turbulent flow are poorly understood as are the roles of passive transport versus active behaviors. Because microorganisms are smaller than the Kolmagorov length (the smallest scale of eddies in turbulent flow), they experience turbulence as a series of linear gradients in the velocity that vary in time. While the average strength of these gradients and a timescale can be computed from some typical characteristics of the flow, such as the turbulent kinetic energy or the dissipation rate, there are indications that organisms are disproportionally affected by rare, extreme events. Understanding the frequency of such events in different environments will be critical to understanding how microorganisms respond to and navigate in turbulence. To understand the hydrodynamic cues that microorganisms experience in the ocean we must measure velocity gradients in realistic turbulent flow on the spatial and temporal scales encountered by microorganisms. We have been exploring the effect of the spatial resolution of PIV and DNS of turbulent flow on the presence of velocity gradients of different magnitudes at the scale of microorganisms. Here we present some results of PIV taken at different resolutions in turbulent flow over rough biological substrata to illustrate the challenges of quantifying the fluctuations in velocity gradients encountered by aquatic microorganisms.

  18. [Effects of legume-oat intercropping on abundance and community structure of soil N2-fixing bacteria].

    Science.gov (United States)

    Yang, Ya Dong; Feng, Xiao Min; Hu, Yue Gao; Ren, Chang Zhong; Zeng, Zhao Hai

    2017-03-18

    In this study, real-time PCR and high-throughput sequencing approaches were employed to investigate the abundance and community structure of N 2 -fixing bacteria in a field experiment with three planting patterns (Oat monoculture, O; Soybean-oat intercropping, OSO; Mung bean-oat intercropping, OMO). The results showed that soil chemical properties varied significantly in different soil samples (P<0.05). The abundance of nifH gene varied from 1.75×10 10 to 7.37×10 10 copies·g -1 dry soil in all soil samples. The copy numbers of nifH gene in OSO and OMO were 2.18, 2.64, and 1.92, 2.57 times as much as that in O at jointing and mature stages, with a significant decline from jointing to mature stage for all treatments (P<0.05). Rarefaction curve and cove-rage results proved the nifH gene sequencing results were reliable, and the diversity index showed that the N 2 -fixing bacteria diversity of OSO was much higher than that of O. Azohydromonas, Azotobacter, Bradyrhizobium, Skermanella and other groups that could not be classified are the dominant genera, with significant differences in proportion of these dominant groups observed among all soil samples (P<0.05). Venn and PCA analysis indicated that there were greater differences of nifH gene communities between jointing and mature stages; however, the OSO and OMO had similar communities in both stages. All these results confirmed that legume-oat intercropping significantly increased the abundance and changed the community composition of N 2 -fixing bacteria in oat soils.

  19. X-ray microanalytical studies of mineral elements in the tripartite symbiosis between lima bean, N2-fixing bacteria and mycorrhizal fungi.

    Science.gov (United States)

    Rodak, Bruna Wurr; Freitas, Douglas Siqueira; Bamberg, Soraya Marx; Carneiro, Marco Aurélio Carbone; Guilherme, Luiz Roberto Guimarães

    2017-01-01

    The symbiosis between legumes, arbuscular mycorrhizal (AM) fungi, and N 2 -fixing bacteria (NFB) provides mutual nutritional gains. However, assessing the nutritional status of the microorganisms is a difficult task. A methodology that could assess this status, in situ, could assist managing these organisms in agriculture. This study used X-ray microanalyses to quantify and locate mineral elements in structures formed in a tripartite symbiosis. Lima bean (Phaseolus lunatus L. Walp) was cultivated in pots under greenhouse conditions, to which we have added AM fungal isolates (Glomus macrocarpum and Acaulospora colombiana) and NFB (Bradyrhizobium japonicum) inocula. Uninoculated control plants were also included. Symbionts were evaluated at the onset of flowering. Quantification of the mineral elements in the symbiotic components was performed using energy dispersive X-ray spectroscopy (EDX) and a scanning electron microscopy (SEM) was used to identify structures. EDX analysis detected 13 elements with the most abundant being N, Ca, and Se, occurring in all tissues, Fe in roots, Ni and Al in epidermis and P and Mo in nodules. Elemental quantification in fungal structures was not possible. The distribution of elements was related to their symbiotic function. X-ray microanalysis can be efficiently applied for nutritional diagnosis in tripartite symbiosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Transgenic alfalfa (Medicago sativa) with increased sucrose phosphate synthase activity shows enhanced growth when grown under N2-fixing conditions.

    Science.gov (United States)

    Gebril, Sayed; Seger, Mark; Villanueva, Fabiola Muro; Ortega, Jose Luis; Bagga, Suman; Sengupta-Gopalan, Champa

    2015-10-01

    Overexpression of SPS in alfalfa is accompanied by early flowering, increased plant growth and an increase in elemental N and protein content when grown under N2-fixing conditions. Sucrose phosphate synthase (SPS; EC 2.3.1.14) is the key enzyme in the synthesis of sucrose in plants. The outcome of overexpression of SPS in different plants using transgenic approaches has been quite varied, but the general consensus is that increased SPS activity is associated with the production of new sinks and increased sink strength. In legumes, the root nodule is a strong C sink and in this study our objective was to see how increasing SPS activity in a legume would affect nodule number and function. Here we have transformed alfalfa (Medicago sativa, cv. Regen SY), with a maize SPS gene driven by the constitutive CaMV35S promoter. Our results showed that overexpression of SPS in alfalfa, is accompanied by an increase in nodule number and mass and an overall increase in nitrogenase activity at the whole plant level. The nodules exhibited an increase in the level of key enzymes contributing to N assimilation including glutamine synthetase and asparagine synthetase. Moreover, the stems of the transformants showed higher level of the transport amino acids, Asx, indicating increased export of N from the nodules. The transformants exhibited a dramatic increase in growth both of the shoots and roots, and earlier flowering time, leading to increased yields. Moreover, the transformants showed an increase in elemental N and protein content. The overall conclusion is that increased SPS activity improves the N status and plant performance, suggesting that the availability of more C in the form of sucrose enhances N acquisition and assimilation in the nodules.

  1. MASS LOSS AND NITROGEN DYNAMICS DURING THE DECOMPOSITION OF A N-LABELED N2-FIXING EPOPHYTIC LICHEN, LOBARIA OREGANA (TUCK.) MULL. ARG.

    Science.gov (United States)

    We studied mass loss and nitrogen dynamics during fall and spring initiated decomposition of an N2-fixing epiphytic lichen, Lobaria oregana (Tuck.) Mull. Arg. using 15N. We developed a method of labeling lichens with 15N that involved spraying lichen material with a nutrient sol...

  2. Soil 13C–15N dynamics in an N2-fixing clover system under long-term exposure to elevated atmospheric CO2

    NARCIS (Netherlands)

    Groenigen, van C.J.; Six, J.; Harris, D.; Blum, H.; Kessel, van C.

    2003-01-01

    Reduced soil N availability under elevated CO2 may limit the plant's capacity to increase photosynthesis and thus the potential for increased soil C input. Plant productivity and soil C input should be less constrained by available soil N in an N2-fixing system. We studied the effects of Trifolium

  3. Beijerinckia derxii stimulates the viability of non-N2-fixing bacteria in nitrogen-free media

    Directory of Open Access Journals (Sweden)

    Barbosa Heloiza R.

    2000-01-01

    Full Text Available The interactions between the nitrogen-fixing microorganism Beijerinckia derxii with two non-diazotrophic bacteria, either Escherichia coli or a facultative sulphur-oxidizing chemolitotroph, were studied in mixed cultures. Direct and indirect contact between B. derxii and E. coli were tested. B. derxii increased CFU numbers and/or maintained the viability of the non-diazotrophic bacteria, but neither growth nor nitrogenase activity of the nitrogen-fixing bacterium were affected by either partner.

  4. Antagonism at combined effects of chemical fertilizers and carbamate insecticides on the rice-field N2-fixing cyanobacterium Cylindrospermum sp. in vitro

    OpenAIRE

    Padhy Rabindra N.; Nayak Nabakishore; Rath Shakti

    2014-01-01

    Effects of chemical fertilizers (urea, super phosphate and potash) on toxicities of two carbamate insecticides, carbaryl and carbofuran, individually to the N2-fixing cyanobacterium, Cylindrospermum sp. were studied in vitro at partially lethal levels (below highest permissive concentrations) of each insecticide. The average number of vegetative cells between two polar heterocysts was 16.3 in control cultures, while the mean value of filament length increased in the presence of chemical ferti...

  5. Combined Effects of CO2 and Light on the N-2-Fixing Cyanobacterium Trichodesmium IMS101: A Mechanistic View

    Czech Academy of Sciences Publication Activity Database

    Levitan, O.; Kranz, S. A.; Spungin, D.; Prášil, Ondřej; Rost, B.; Berman-Frank, I.

    2010-01-01

    Roč. 154, č. 1 (2010), s. 346-356 ISSN 0032-0889 R&D Projects: GA ČR GA206/08/1683 Institutional research plan: CEZ:AV0Z50200510 Keywords : cyanobacterium Trichodesmium * ocean * photosystem I Subject RIV: EE - Microbiology, Virology Impact factor: 6.451, year: 2010

  6. Bioturbation determines the response of benthic ammonia-oxidizing microorganisms to ocean acidification

    Science.gov (United States)

    Laverock, B.; Kitidis, V.; Tait, K.; Gilbert, J. A.; Osborn, A. M.; Widdicombe, S.

    2013-01-01

    Ocean acidification (OA), caused by the dissolution of increasing concentrations of atmospheric carbon dioxide (CO2) in seawater, is projected to cause significant changes to marine ecology and biogeochemistry. Potential impacts on the microbially driven cycling of nitrogen are of particular concern. Specifically, under seawater pH levels approximating future OA scenarios, rates of ammonia oxidation (the rate-limiting first step of the nitrification pathway) have been shown to dramatically decrease in seawater, but not in underlying sediments. However, no prior study has considered the interactive effects of microbial ammonia oxidation and macrofaunal bioturbation activity, which can enhance nitrogen transformation rates. Using experimental mesocosms, we investigated the responses to OA of ammonia oxidizing microorganisms inhabiting surface sediments and sediments within burrow walls of the mud shrimp Upogebia deltaura. Seawater was acidified to one of four target pH values (pHT 7.90, 7.70, 7.35 and 6.80) in comparison with a control (pHT 8.10). At pHT 8.10, ammonia oxidation rates in burrow wall sediments were, on average, fivefold greater than in surface sediments. However, at all acidified pH values (pH ≤ 7.90), ammonia oxidation rates in burrow sediments were significantly inhibited (by 79–97%; p < 0.01), whereas rates in surface sediments were unaffected. Both bacterial and archaeal abundances increased significantly as pHT declined; by contrast, relative abundances of bacterial and archaeal ammonia oxidation (amoA) genes did not vary. This research suggests that OA could cause substantial reductions in total benthic ammonia oxidation rates in coastal bioturbated sediments, leading to corresponding changes in coupled nitrogen cycling between the benthic and pelagic realms. PMID:23980243

  7. Effects of long-term elevated CO2 on N2-fixing, denitrifying and nitrifying enzyme activities in forest soils under Pinus sylvestriformis in Changbai Mountain

    Institute of Scientific and Technical Information of China (English)

    ZHENG Jun-Qiang; HAN Shi-Jie; REN Fei-Rong; ZHOU Yu-Mei; ZHANG Yan

    2008-01-01

    A study was conducted to determine the effects of elevated CO2 on soil N process at Changbai Mountain in Jilin Province,northeastern China (42o24'N,128o06'E,and 738 m elevation).A randomized complete block design of ambient and elevated CO2 was established in an open-top chamber facility in the spring of 1999.Changpai Scotch pine (Pinus sylvestris var.sylvestriformis seeds were sowed in May,1999 and CO2 fumigation treatments began after seeds germination.In each year,the exposure started at the end of April and stopped at the end of October.Soil samples were collected in June and August 2006 and in June 2007,and soil nitrifying,denitrifying and N2-fixing enzyme activities were measured.Results show that soil nitrifying enzyme activities (NEA) in the 5-10 cm soil layer were significantly increased at elevated CO2 by 30.3% in June 2006,by 30.9% in August 2006 and by 11.3% in June 2007.Soil denitrifying enzyme activities (DEA) were significantly decreased by elevated CO2 treatment in June 2006 (P < 0.012) and August 2006 (P < 0.005) samplings in our study; no significant difference was detected in June 2007,and no significant changes in N2-fixing enzyme activity were found.This study suggests that elevated CO2 can alter soil nitrifying enzyme and denitrifying enzyme activities.

  8. Assessment of N2 fixing efficiency of Beijerinckia indica and Azospirillum brasilense in Sorghum (Sorghum bicolor (L.) moench) using 15N tracer

    International Nuclear Information System (INIS)

    Kanimoli, S.; Marimuthu, P.; Arulmozhiselvan, K.

    2010-01-01

    For studying the benefits of inoculation of N 2 fixing diazotrophs in the root zone of sorghum crop, a pot culture was conducted on neutral red sandy loam soil with sorghum cv. CO26, using 15 N tracer. At the end of 45 days duration after sowing, Beijerinckia indica inoculation contributed 56.9 per cent N derived from N 2 fixation, out of total N concentration in whole drymatter of sorghum plant. It proved to be the efficient N 2 fixer by contributing N from N 2 fixation to the tune of 17.6 Kg -1 . Accumulation of N derived from N 2 fixation from B. indica was primarily in leaf blade (50.0%) followed by stem (31.8%), leaf sheath (14.0%) and root (4.2%). Inoculation of Azospirillum brasllense accelerated uptake of N from soil and fertilizer N sources compared to B. indica and hence registered low N fixation. (author)

  9. Quantifying N2-fixed by groundnut (Arachis hypogaea L.) as compared to some summer legumes using ''1''5N methodology with different reference crops

    International Nuclear Information System (INIS)

    Adlan, M. A. M.; Mukhtar, N. O.

    2004-01-01

    Using the ''1''5N methodology, one of the cultivar of groundnut repeated once (as groundnut 1 and 2) and one cultivar of each of the summer legumes guar, pigeon pea and mungbean were studied (a) to determine the amounts of nitrogen fixed by these legumes using different reference crops and (b) to compare N-fixation by groundnut to that of the above mentioned summer legumes. The reference crops used were, sorghum, soybean and a non-nodulating groundnut isoline. Each of the studied legumes and reference crops was grown at the Gezira Research Station Farm, in a microplot of 2.4 m''2 situated at one side of a main-plot of 24 m''2. The N 2 fixing legumes guar, mung bean, and pigeon pea and sorghum were given 20 kg N/ha as urea at 5.0% ''1''5N atom excess, and the reference crops of soybean and non -nodulating groundnut were given 100 kg N/ha at 1.0% ''1''5N atom excess. ''1''4N/''1''5N ratios were determined in plants sampled from the microplots. The results showed that pigeon pea and guar could compete well with groundnut as N 2 -fixers. Levels of fixation (%Ndfa) were 79% (108 kg N/ha), 77% (138 kg N/ha) and 80% (70 kg N/ha) of the total crop's N need for guar, groundnut and pigeon pea, respectively. Mungbean fixed about 12% (6 kg N/ha) of its N need. The variation in the amounts of N 2 fixed in kg/ha is dependent on the total plant N yield of each legume which was 160-180, 139, 87 and 68 for groundnut, guar, pigeon pea and mug bean, respectively. The non-nodulating groundnut was a superior reference crop over sorghum and soybean. Thus, the studied reference crops can be listed in a descending order of excellence as follows: non-nodulating groundnut, sorghum, soybean.(Author)

  10. Implications of Ocean Acidification for Marine Microorganisms from the Free-Living to the Host-Associated

    Directory of Open Access Journals (Sweden)

    Paul A O'Brien

    2016-04-01

    Full Text Available Anthropogenic CO2 emissions are causing oceans to become more acidic, with consequences for all marine life including microorganisms. Studies reveal that from the microbes that occupy the open ocean to those intimately associated with their invertebrate hosts, changing ocean chemistry will alter the critical functions of these important organisms. Our current understanding indicates that bacterial communities associated with their host will shift as pH drops by another 0.2-0.4 units over the next 100 years. It is unclear what impacts this will have for host health, however increased vulnerability to disease seems likely for those associated with reef corals. Natural CO2 seeps have provided a unique setting for the study of microbial communities under OA in situ, where shifts in the bacterial communities associated with corals at the seep are correlated with a decline in abundance of the associated coral species. Changes to global biogeochemical cycles also appear likely as photosynthesis and nitrogen fixation by pelagic microbes becomes enhanced under low pH conditions. However, recent long-term studies have shown that pelagic microbes are also capable of evolutionary adaptation, with some physiological responses to a decline in pH restored after hundreds of generations at high pCO2 levels. The impacts of ocean acidification (OA also will not work in isolation, thus synergistic interactions with other potential stressors, such as rising seawater temperatures, will likely exacerbate the microbial response to OA. This review discusses our existing understanding of the impacts of OA on both pelagic and host-associated marine microbial communities, whilst highlighting the importance of controlled laboratory studies and in situ experiments, to fill the current gaps in our knowledge.

  11. 15N enrichment of soil NH4+-N as an alternative non-N2-fixing reference for assessing varietal differences in N2 fixation of rice

    International Nuclear Information System (INIS)

    Shrestha, R.K.; Ladha, J.K.

    1996-01-01

    A pot experiment in the greenhouse was conducted to assess the usefulness of 15 N enrichment of soil NH 4 + -N as an alternative to a non-fixing reference plant to determine varietal differences in N 2 fixation among rice varieties. Diverse rice genotypes were grown in a 15 N stabilized soil obtained after 6 wk of application under flooded conditions. Atom % 15 N excess of soil NH 4 + -N was decreased exponentially with amount of N mineralized (r=99). Close agreement was observed between the 15 N enrichment of reference rice plant and 15 N enrichment of KCl extractable NH 4 + -N from unplanted pots maintained in the greenhouse. Whole plant atom % 15 N excess was inversely correlated within growth duration. Therefore, it was necessary to calculate Ndfa within growth duration. Ndfa estimated within the growth duration using 15 N enrichment of soil NH 4 + -N and reference rice genotype correlated almost perfectly (r=998). Thus the study demonstrated the potential of using 15 N enrichment of soil NH 4 + -N as a non-N 2 fixing reference for reliable estimate of biological nitrogen fixation by nonlegumes under flooded conditions. (author)

  12. Antagonism at combined effects of chemical fertilizers and carbamate insecticides on the rice-field N2-fixing cyanobacterium Cylindrospermum sp. in vitro

    Directory of Open Access Journals (Sweden)

    Padhy Rabindra N.

    2014-03-01

    Full Text Available Effects of chemical fertilizers (urea, super phosphate and potash on toxicities of two carbamate insecticides, carbaryl and carbofuran, individually to the N2-fixing cyanobacterium, Cylindrospermum sp. were studied in vitro at partially lethal levels (below highest permissive concentrations of each insecticide. The average number of vegetative cells between two polar heterocysts was 16.3 in control cultures, while the mean value of filament length increased in the presence of chemical fertilizers, individually. Urea at the 10 ppm level was growth stimulatory and at the 50 ppm level it was growth inhibitory in control cultures, while at 100 ppm it was antagonistic, i.e. toxicity-enhancing along with carbaryl, individually to the cyanobacterium, antagonism was recorded. Urea at 50 ppm had toxicity reducing effect with carbaryl or carbofuran. At 100 and 250 ppm carbofuran levels, 50 ppm urea only had a progressive growth enhancing effect, which was marked well at 250 ppm carbofuran level, a situation of synergism. Super phosphate at the 10 ppm level only was growth promoting in control cultures, but it was antagonistic at its higher levels (50 and 100 ppm along with both insecticides, individually. Potash (100, 200, 300 and 400 ppm reduced toxicity due to carbaryl 20 and carbofuran 250 ppm levels, but potash was antagonistic at the other insecticide levels. The data clearly showed that the chemical fertilizers used were antagonistic with both the insecticides during toxicity to Cylindrospermum sp.

  13. Antagonism at combined effects of chemical fertilizers and carbamate insecticides on the rice-field N2-fixing cyanobacterium Cylindrospermum sp. in vitro

    Science.gov (United States)

    Nayak, Nabakishore; Rath, Shakti

    2014-01-01

    Effects of chemical fertilizers (urea, super phosphate and potash) on toxicities of two carbamate insecticides, carbaryl and carbofuran, individually to the N2-fixing cyanobacterium, Cylindrospermum sp. were studied in vitro at partially lethal levels (below highest permissive concentrations) of each insecticide. The average number of vegetative cells between two polar heterocysts was 16.3 in control cultures, while the mean value of filament length increased in the presence of chemical fertilizers, individually. Urea at the 10 ppm level was growth stimulatory and at the 50 ppm level it was growth inhibitory in control cultures, while at 100 ppm it was antagonistic, i.e. toxicity-enhancing along with carbaryl, individually to the cyanobacterium, antagonism was recorded. Urea at 50 ppm had toxicity reducing effect with carbaryl or carbofuran. At 100 and 250 ppm carbofuran levels, 50 ppm urea only had a progressive growth enhancing effect, which was marked well at 250 ppm carbofuran level, a situation of synergism. Super phosphate at the 10 ppm level only was growth promoting in control cultures, but it was antagonistic at its higher levels (50 and 100 ppm) along with both insecticides, individually. Potash (100, 200, 300 and 400 ppm) reduced toxicity due to carbaryl 20 and carbofuran 250 ppm levels, but potash was antagonistic at the other insecticide levels. The data clearly showed that the chemical fertilizers used were antagonistic with both the insecticides during toxicity to Cylindrospermum sp. PMID:26038669

  14. Assessing the viability of microorganisms in the ballast water of vessels transiting the North Atlantic Ocean.

    Science.gov (United States)

    Steichen, Jamie L; Quigg, Antonietta

    2015-12-15

    Testing phytoplankton viability within ballast tanks and receiving waters of ballast water discharge remain understudied. Potentially harmful dinoflagellates and diatoms are transported via ballast water to Galveston Bay, Texas (USA), home to three major ports: Houston, Texas City and Galveston. Ballast water from vessels transiting the North Atlantic Ocean was inoculated into treatments representing low and high salinity conditions similar to the Ports of Houston and Galveston respectively. Phytoplankton in ballast water growout experiments were deemed viable and showed growth in low and mid salinities with nutrient enrichment. Molecular methods identified several genera: Dinophysis, Gymnodinium, Gyrodinium, Heterocapsa, Peridinium, Scrippsiella, Chaetoceros and Nitzschia. These phytoplankton genera were previously identified in Galveston Bay except Scrippsiella. Phytoplankton, including those capable of forming harmful algal blooms leading to fish and shellfish kills, are transported to Galveston Bay via ballast water, and are viable when introduced to similar salinity conditions found in Galveston Bay ports. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Characterization of N2-fixing plant growth promoting endophytic and epiphytic bacterial community of Indian cultivated and wild rice (Oryza spp.) genotypes.

    Science.gov (United States)

    Banik, Avishek; Mukhopadhaya, Subhra Kanti; Dangar, Tushar Kanti

    2016-03-01

    The diversity of endophytic and epiphytic diazotrophs in different parts of rice plants has specificity to the niche (i.e. leaf, stem and root) of different genotypes and nutrient availability of the organ. Inoculation of the indigenous, polyvalent diazotrophs can facilitate and sustain production of non-leguminous crops like rice. Therefore, N2-fixing plant growth promoting bacteria (PGPB) were isolated from different parts of three Indian cultivated [Oryza sativa L. var. Sabita (semi deep/deep water)/Swarna (rain fed shallow lowland)/Swarna-Sub1(submergence tolerant)] and a wild (O. eichingeri) rice genotypes which respond differentially to nitrogenous fertilizers. Thirty-five isolates from four rice genotypes were categorized based on acetylene reduction assay on nitrogenase activity, biochemical tests, BIOLOG and 16S rRNA gene sequencing. The bacteria produced 9.36-155.83 nmole C2H4 mg(-1) dry bacteria h(-1) and among them nitrogenase activity of 11 potent isolates was complemented by nifH-sequence analysis. Phylogenetic analysis based on 16S rDNA sequencing divided them into five groups (shared 95-100 % sequence homology with type strains) belonging to five classes-alpha (Ancylobacter, Azorhizobium, Azospirillum, Rhizobium, Bradyrhizobium, Sinorhizobium, Novosphingobium, spp.), beta (Burkholderia sp.), gamma (Acinetobacter, Aeromonas, Azotobacter, Enterobacter, Klebsiella, Pantoea, Pseudomonas, Stenotrophomonas spp.) Proteobacteria, Bacilli (Bacillus, Paenibacillus spp.) and Actinobacteria (Microbacterium sp.). Besides, all bacterial strains possessed the intrinsic PGP traits of like indole (0.44-7.4 µg ml(-1)), ammonia (0.18-6 mmol ml(-1)), nitrite (0.01-3.4 mol ml(-1)), and siderophore (from 0.16-0.57 μmol ml(-1)) production. Inoculation of rice (cv. Swarna) seedlings with selected isolates had a positive impact on plant growth parameters like shoot and root elongation which was correlated with in vitro PGP attributes. The results indicated that the

  16. Leaf d15N as a physiological indicator of the responsiveness of N2-fixing alfalfa plants to elevated [CO2], temperature and low water availability

    Directory of Open Access Journals (Sweden)

    Idoia eAriz

    2015-08-01

    Full Text Available The natural 15N/14N isotope composition (δ15N of a tissue is a consequence of its N source and N physiological mechanisms in response to the environment. It could potentially be used as a tracer of N metabolism in plants under changing environmental conditions, where primary N metabolism may be complex, and losses and gains of N fluctuate over time. In order to test the utility of δ15N as an indicator of plant N status in N2-fixing plants grown under various environmental conditions, alfalfa (Medicago sativa L. plants were subjected to distinct conditions of [CO2] (400 versus 700 mol mol-1, temperature (ambient versus ambient + 4ºC and water availability (fully watered versus water deficiency - WD. As expected, increased [CO2] and temperature stimulated photosynthetic rates and plant growth, whereas these parameters were negatively affected by WD. The determination of δ15N in leaves, stems, roots and nodules showed that leaves were the most representative organs of the plant response to increased [CO2] and WD. Depletion of heavier N isotopes in plants grown under higher [CO2] and WD conditions reflected decreased transpiration rates, but could also be related to a higher N demand in leaves, as suggested by the decreased leaf N and total soluble protein (TSP contents detected at 700 mol mol-1 [CO2] and WD conditions. In summary, leaf δ15N provides relevant information integrating parameters which condition plant responsiveness (e.g. photosynthesis, TSP, N demand and water transpiration to environmental conditions.

  17. Enzyme kinetics, inhibitors, mutagenesis and electron paramagnetic resonance analysis of dual-affinity nitrate reductase in unicellular N(2)-fixing cyanobacterium Cyanothece sp. PCC 8801.

    Science.gov (United States)

    Wang, Tung-Hei; Chen, Yung-Han; Huang, Jine-Yung; Liu, Kang-Cheng; Ke, Shyue-Chu; Chu, Hsiu-An

    2011-11-01

    The assimilatory nitrate reductase (NarB) of N(2)-fixing cyanobacterium Cyanothece sp. PCC 8801 is a monomeric enzyme with dual affinity for substrate nitrate. We purified the recombinant NarB of Cyanothece sp. PCC 8801 and further investigated it by enzyme kinetics analysis, site-directed mutagenesis, inhibitor kinetics analysis, and electron paramagnetic resonance (EPR) spectroscopy. The NarB showed 2 kinetic regimes at pH 10.5 or 8 and electron-donor conditions methyl viologen or ferredoxin (Fd). Fd-dependent NR assay revealed NarB with very high affinity for nitrate (K(m)1, ∼1μM; K(m)2, ∼270μM). Metal analysis and EPR results showed that NarB contains a Mo cofactor and a [4Fe-4S] cluster. In addition, the R352A mutation on the proposed nitrate-binding site of NarB greatly altered both high- and low-affinity kinetic components. Furthermore, the effect of azide on the NarB of Cyanothece sp. PCC 8801 was more complex than that on the NarB of Synechococcus sp. PCC 7942 with its single kinetic regime. With 1mM azide, the kinetics of the wild-type NarB was transformed from 2 kinetic regimes to hyperbolic kinetics, and its activity was enhanced significantly under medium nitrate concentrations. Moreover, EPR results also suggested a structural difference between the two NarBs. Taken together, our results show that the NarB of Cyanothece sp. PCC 8801 contains only a single Mo-catalytic center, and we rule out that the enzyme has 2 independent, distinct catalytic sites. In addition, the NarB of Cyanothece sp. PCC 8801 may have a regulatory nitrate-binding site. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  18. Microorganism immobilization

    Science.gov (United States)

    Compere, Alicia L.; Griffith, William L.

    1981-01-01

    Live metabolically active microorganisms are immobilized on a solid support by contacting particles of aggregate material with a water dispersible polyelectrolyte such as gelatin, crosslinking the polyelectrolyte by reacting it with a crosslinking agent such as glutaraldehyde to provide a crosslinked coating on the particles of aggregate material, contacting the coated particles with live microorganisms and incubating the microorganisms in contact with the crosslinked coating to provide a coating of metabolically active microorganisms. The immobilized microorganisms have continued growth and reproduction functions.

  19. Study on the killing of oceanic harmful micro-organisms in ship's ballast water using oxygen active particles

    International Nuclear Information System (INIS)

    Chen, C; Meng, X Y; Bai, M D; Tian, Y P; Jing, Y

    2013-01-01

    Global Environment Facility has identified that the spread of marine invasive alien species is one of the four major risk factors threatening the safety of global marine environments. Ballast water discharge is the main cause of biological invasion. With physical methods of strong electric field ionization discharge at atmospheric pressure, O 2 and sea water (gaseous) were ionized, and then dissociated to a number of oxygen active particles (ROS) such as ·OH, O 2 + , H 2 O + , etc. ROS was injected into 0.6 t h −1 ballast water treatment system to form high concentration ROS solution in order to kill the harmful micro-organisms in ballast water. According to the land-based test standard of International Maritime Organization (IMO) Guidelines for Approval of Ballast Water Management Systems (G8), this paper concludes that single-cell algae of 3.0 × 10 4 cell ml −1 and bacteria of 2.0 × 10 4 cfu ml −1 were killed by ROS solution of 2.0 ppm. Death rate could reach almost 100%. The results meet the requirements of Regulation D-2 of International Convention for the Control and Management of Ships' Ballast Water and Sediments completely.

  20. Lignite microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Bulankina, M.A.; Lysak, L.V.; Zvyagintsev, D.G. [Moscow MV Lomonosov State University, Moscow (Russian Federation). Faculty of Soil Science

    2007-03-15

    The first demonstration that samples of lignite at a depth of 10 m are considerably enriched in bacteria is reported. According to direct microscopy, the abundance of bacteria was about 10{sup 7} cells/g. About 70% of cells had intact cell membranes and small size, which points to their anabiotic state. The fungal mycelium length was no more than 1 m. Lignite inoculation onto solid glucose-yeast-peptone medium allowed us to isolate bacteria of the genera Bacillus, Rhodococcus, Arthrobacter, Micrococcus, Spirillum, and Cytophaga. Representatives of the genera Penicillium and Trichoderma were identified on Czapek medium. Moistening of lignite powder increased the microbial respiration rate and microbial and fungal abundance but did not increase their generic diversity. This finding suggests that the studied microorganisms are autochthonous to lignite.

  1. Fossilized glycolipids reveal past oceanic N2 fixation by heterocystous cyanobacteria

    Science.gov (United States)

    Bauersachs, Thorsten; Speelman, Eveline N.; Hopmans, Ellen C.; Reichart, Gert-Jan; Schouten, Stefan; Damsté, Jaap S. Sinninghe

    2010-01-01

    N2-fixing cyanobacteria play an essential role in sustaining primary productivity in contemporary oceans and freshwater systems. However, the significance of N2-fixing cyanobacteria in past nitrogen cycling is difficult to establish as their preservation potential is relatively poor and specific biological markers are presently lacking. Heterocystous N2-fixing cyanobacteria synthesize unique long-chain glycolipids in the cell envelope covering the heterocyst cell to protect the oxygen-sensitive nitrogenase enzyme. We found that these heterocyst glycolipids are remarkably well preserved in (ancient) lacustrine and marine sediments, unambiguously indicating the (past) presence of N2-fixing heterocystous cyanobacteria. Analysis of Pleistocene sediments of the eastern Mediterranean Sea showed that heterocystous cyanobacteria, likely as epiphytes in symbiosis with planktonic diatoms, were particularly abundant during deposition of sapropels. Eocene Arctic Ocean sediments deposited at a time of large Azolla blooms contained glycolipids typical for heterocystous cyanobacteria presently living in symbiosis with the freshwater fern Azolla, indicating that this symbiosis already existed in that time. Our study thus suggests that heterocystous cyanobacteria played a major role in adding “new” fixed nitrogen to surface waters in past stratified oceans. PMID:20966349

  2. Assessing the biological potential of N2-fixing Leguminosae in ...

    African Journals Online (AJOL)

    Administrator

    2007-02-19

    Feb 19, 2007 ... legume genotypes or host/strain combinations for increased plant growth would help identify superior symbiotic ... are highly leached acidic soils (85% sand) with low ... quently, identifying crop species that are adapted to low.

  3. Microorganisms in food technology

    Energy Technology Data Exchange (ETDEWEB)

    Rose, A H

    1981-11-01

    Man has been using microorganisms for thousands of years to make bread, cheese, beer, wine, etc. Today, microorganisms can be specially grown or genetically manipulated so as to synthesize high-quality proteins even from low-grade basic materials.

  4. Biosurfactants from marine microorganisms

    Directory of Open Access Journals (Sweden)

    Suppasil Maneerat

    2005-11-01

    Full Text Available Biosurfactants are the surface-active molecules synthesized by microorganisms. With the advantage of environmental compatibility, the demand for biosurfactants has been steadily increasing and may eventually replace their chemically synthesized counterparts. Marine biosurfactants produced by some marine microorganisms have been paid more attention, particularly for the bioremediation of the sea polluted by crude oil. This review describes screening of biosurfactant-producing microorganisms, the determination of biosurfactant activity as well as the recovery of marine surfactant. The uses of marine biosurfactants for bioremediation are also discussed.

  5. Microorganisms involved in MIC

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, K. [Danish Technological Institute (Denmark)

    2011-07-01

    Microbiologically influenced corrosion (MIC) is a widespread problem that is difficult to detect and assess because of its complex mechanism. This paper presents the involvement of microorganisms in MIC. Some of the mechanisms that cause MIC include hydrogen consumption, production of acids, anode-cathode formation and electron shuttling. A classic bio-corrosive microorganism in the oil and gas industry is sulphate-reducing prokaryotes (SRP). Methanogens also increase corrosion rates in metals. Some of the phylogenetic orders detected while studying SRP and methanogens are archaeoglobales, clostridiales, methanosarcinales and methanothermococcus. There were some implications, such as growth of SRP not being correlated with growth of methanogens; methanogens were included in MIC risk assessment. A few examples are used to display how microorganisms are involved in topside corrosion and microbial community in producing wells. From the study, it can be concluded that, MIC risk assessment includes system data and empirical knowledge of the distribution and number of microorganisms in the system.

  6. Marine microorganisms. Umi no biseibutsu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, U. (Hiroshima University, Hiroshima (Japan). Faculty of Applied Biological Science)

    1992-11-10

    This paper explains properties, interactions, and activities of marine microorganisms. Marine bacteria include bacteria of vibrio family of arteromonas genus, luminous bacteria, and aerobic photosynthetic bacteria. Majority of marine bacteria is halophilic, and many proliferate at 5[degree]C or lower. Some of them can proliferate at 20[degree]C to 30[degree]C, or as high temperature as 80[degree]C and higher. Spongiaria and tumicata have many symbiotic microorganisms, and genes equivalent to luminous bacteria genes were discovered in DNA of light emitting organs in luminous fishes. It was verified that animal groups in upwelling zones are supported by bacteria that assimilate inorganics supplied from ocean bottoms. Marine bacteria decompose almost all of organics brought in from land to sea, and those produced in sea. Marine bacteria engage in complex interrelations with other organisms for competition, antagonism, parasitism, and symbiosis. The bacteria make antibacterial substances, anti-algae bacteria, enzyme inhibitors, toxins, pharmacologically active substances, and such physiologically active substances as deposition promoting substances to undersea structures including shells and barnacles, and deposition blocking substances. 53 refs., 3 figs.

  7. Micro-Organ Device

    Science.gov (United States)

    Gonda, Steve R. (Inventor); Chang, Robert C. (Inventor); Starly, Binil (Inventor); Culbertson, Christopher (Inventor); Holtorf, Heidi L. (Inventor); Sun, Wei (Inventor); Leslie, Julia (Inventor)

    2013-01-01

    A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

  8. Fossil Microorganisms in Archaean

    Science.gov (United States)

    Astafleva, Marina; Hoover, Richard; Rozanov, Alexei; Vrevskiy, A.

    2006-01-01

    Ancient Archean and Proterozoic rocks are the model objects for investigation of rocks comprising astromaterials. The first of Archean fossil microorganisms from Baltic shield have been reported at the last SPIE Conference in 2005. Since this confeence biomorphic structures have been revealed in Archean rocks of Karelia. It was determined that there are 3 types of such bion structures: 1. structures found in situ, in other words microorganisms even-aged with rock matrix, that is real Archean fossils biomorphic structures, that is to say forms inhabited early formed rocks, and 3. younger than Archean-Protherozoic minerali microorganisms, that is later contamination. We made attempt to differentiate these 3 types of findings and tried to understand of burial of microorganisms. The structures belongs (from our point of view) to the first type, or real Archean, forms were under examination. Practical investigation of ancient microorganisms from Green-Stone-Belt of Northern Karelia turns to be very perspective. It shows that even in such ancient time as Archean ancient diverse world existed. Moreover probably such relatively highly organized cyanobacteria and perhaps eukaryotic formes existed in Archean world.

  9. Bioplastics from microorganisms.

    Science.gov (United States)

    Luengo, José M; García, Belén; Sandoval, Angel; Naharro, Germán; Olivera, Elías R

    2003-06-01

    The term 'biomaterials' includes chemically unrelated products that are synthesised by microorganisms (or part of them) under different environmental conditions. One important family of biomaterials is bioplastics. These are polyesters that are widely distributed in nature and accumulate intracellularly in microorganisms in the form of storage granules, with physico-chemical properties resembling petrochemical plastics. These polymers are usually built from hydroxy-acyl-CoA derivatives via different metabolic pathways. Depending on their microbial origin, bioplastics differ in their monomer composition, macromolecular structure and physical properties. Most of them are biodegradable and biocompatible, which makes them extremely interesting from the biotechnological point of view.

  10. Motion of magnetotactic microorganisms

    International Nuclear Information System (INIS)

    Esquivel, D.M.S.; Barros, H.G. de P.L. de.

    1985-01-01

    Magnetic moments for different magnetotactic microorganisms are obtained by electron microscopy analyses and studies of motion by optical microscopy. The results are analysed in terms of a model due to C.Bean. The considerations presented suggest that magnetotaxy is an efficient mechanism for orientation only if the time for reorientation is smaller than the cycles of environmental perturbations. (Author) [pt

  11. Bacterial Diversity and Nitrogen Utilization Strategies in the Upper Layer of the Northwestern Pacific Ocean.

    Science.gov (United States)

    Li, Yuan-Yuan; Chen, Xiao-Huang; Xie, Zhang-Xian; Li, Dong-Xu; Wu, Peng-Fei; Kong, Ling-Fen; Lin, Lin; Kao, Shuh-Ji; Wang, Da-Zhi

    2018-01-01

    Nitrogen (N) is a primary limiting nutrient for bacterial growth and productivity in the ocean. To better understand bacterial community and their N utilization strategy in different N regimes of the ocean, we examined bacterial diversity, diazotrophic diversity, and N utilization gene expressions in the northwestern Pacific Ocean (NWPO) using a combination of high-throughput sequencing and real-time qPCR methods. 521 and 204 different operational taxonomic units (OTUs) were identified in the 16s rRNA and nifH libraries from nine surface samples. Of the 16s rRNA gene OTUs, 11.9% were observed in all samples while 3.5 and 15.9% were detected only in N-sufficient and N-deficient samples. Proteobacteria, Cyanobacteria and Bacteroidetes dominated the bacterial community. Prochlorococcus and Pseudoalteromonas were the most abundant at the genus level in N-deficient regimes, while SAR86, Synechococcus and SAR92 were predominant in the Kuroshio-Oyashio confluence region. The distribution of the nifH gene presented great divergence among sampling stations: Cyanobacterium_UCYN-A dominated the N-deficient stations, while clusters related to the Alpha-, Beta- , and Gamma-Proteobacteria were abundant in other stations. Temperature was the main factor that determined bacterial community structure and diversity while concentration of NO X -N was significantly correlated with structure and distribution of N 2 -fixing microorganisms. Expression of the ammonium transporter was much higher than that of urea transporter subunit A ( urtA ) and ferredoxin-nitrate reductase , while urtA had an increased expression in N-deficient surface water. The predicted ammonium transporter and ammonium assimilation enzymes were most abundant in surface samples while urease and nitrogenase were more abundant in the N-deficient regions. These findings underscore the fact that marine bacteria have evolved diverse N utilization strategies to adapt to different N habitats, and that urea metabolism is of

  12. Bacterial Diversity and Nitrogen Utilization Strategies in the Upper Layer of the Northwestern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    Yuan-Yuan Li

    2018-04-01

    Full Text Available Nitrogen (N is a primary limiting nutrient for bacterial growth and productivity in the ocean. To better understand bacterial community and their N utilization strategy in different N regimes of the ocean, we examined bacterial diversity, diazotrophic diversity, and N utilization gene expressions in the northwestern Pacific Ocean (NWPO using a combination of high-throughput sequencing and real-time qPCR methods. 521 and 204 different operational taxonomic units (OTUs were identified in the 16s rRNA and nifH libraries from nine surface samples. Of the 16s rRNA gene OTUs, 11.9% were observed in all samples while 3.5 and 15.9% were detected only in N-sufficient and N-deficient samples. Proteobacteria, Cyanobacteria and Bacteroidetes dominated the bacterial community. Prochlorococcus and Pseudoalteromonas were the most abundant at the genus level in N-deficient regimes, while SAR86, Synechococcus and SAR92 were predominant in the Kuroshio-Oyashio confluence region. The distribution of the nifH gene presented great divergence among sampling stations: Cyanobacterium_UCYN-A dominated the N-deficient stations, while clusters related to the Alpha-, Beta-, and Gamma-Proteobacteria were abundant in other stations. Temperature was the main factor that determined bacterial community structure and diversity while concentration of NOX-N was significantly correlated with structure and distribution of N2-fixing microorganisms. Expression of the ammonium transporter was much higher than that of urea transporter subunit A (urtA and ferredoxin-nitrate reductase, while urtA had an increased expression in N-deficient surface water. The predicted ammonium transporter and ammonium assimilation enzymes were most abundant in surface samples while urease and nitrogenase were more abundant in the N-deficient regions. These findings underscore the fact that marine bacteria have evolved diverse N utilization strategies to adapt to different N habitats, and that urea

  13. Inactivation of Microorganisms

    Science.gov (United States)

    Alzamora, Stella Maris; Guerrero, Sandra N.; Schenk, Marcela; Raffellini, Silvia; López-Malo, Aurelio

    Minimal processing techniques for food preservation allow better retention of product flavor, texture, color, and nutrient content than comparable conventional treatments. A wide range of novel alternative physical factors have been intensely investigated in the last two decades. These physical factors can cause inactivation of microorganisms at ambient or sublethal temperatures (e.g., high hydrostatic pressure, pulsed electric fields, ultrasound, pulsed light, and ultraviolet light). These technologies have been reported to reduce microorganism population in foods while avoiding the deleterious effects of severe heating on quality. Among technologies, high-energy ultrasound (i.e., intensities higher than 1 W/cm2, frequencies between 18 and 100 kHz) has attracted considerable interest for food preservation applications (Mason et al., 1996; Povey and Mason, 1998).

  14. Properties of thermophilic microorganisms

    International Nuclear Information System (INIS)

    Ljungdahl, L.G.

    1984-01-01

    Microorganisms are called thermophilic or extreme thermophilic (caldo-active) if they grow and reproduce over 47 0 C and 70 0 C, respectively. A survey of growth characteristics of thermophiles is presented and it includes those which also live at extreme pH. The prevalent but not completely emcompassing theory of the ability of thermophiles to grow at high temperatures is that they have macromolecules and cell organelles with high thermostability. Work on some proteins and cell organelles from thermophiles is reviewed. The thermostabilities of these components are compared with those of the living cells, and factors which may govern optimum as well as minimum growth temperatures of microorganisms are discussed. Examples are from the literature but also include enzymes involved in tetrahydrofolate metabolism and other proteins of acetogenic therhmophilic bacteria which are presently studied in the author's laboratory

  15. Metal-microorganism interactions

    International Nuclear Information System (INIS)

    Andres, Y.; Thouand, G.; Redercher, S.; Boualam, M.; Texier, A.Cl.; Hoeffer, R.

    1997-01-01

    The physico-chemical procedures of treating the metalliferous effluents are not always adapted to de polluting the slightly concentrated industrial wastes. An alternative idea was advanced, implying the ability of some microorganisms to fix in considerable amounts the metal ions present in aqueous solutions, possibly in a selective way. This approach has been investigated thoroughly during the last 30 years, particularly from a mechanistic point of view. The advantage of the microorganisms lies mainly in the large diversity of bacteria and in their chemical state dependent interaction with metals, as well as, in the possibilities of developing their selective and quantitative separation properties. A biomass from Mycobacterium smegmatis, an acidic alcoholic resistant bacteria, has been used to prepare a bio-sorption support allowing the preferential sorption of thorium as compared to uranium and lanthanum. These studies have been extended to biological polymers such as chitosan and to studies related to bioaccumulation mechanisms and/or to the microbial resistances towards metals

  16. Microorganisms of Grape Berries

    Directory of Open Access Journals (Sweden)

    Kántor Attila

    2017-12-01

    Full Text Available Grape surface is an unstable habitat that changes greatly according to the stage of grape ripening. Different bacteria and yeasts can colonise the surface of grape berry and the diversity of microorganisms depends on the stage of ripening, pesticide application and health condition. The aim of this study was to study the microflora of the surface of grape berries. Altogether, 19 grape samples from Slovakia were collected. The spread plate method was applied and a 100 μL inoculum of each dilution (10−2, 10−3 was plated on TSA, MEA, and MRS agar for isolation of microorganisms from grapes. Proteins were extracted from cells by ethanol/formic acid extraction procedure. MALDI-TOF Mass Spectrometry was used for identification of microorganisms. In total, 11 genera of Gram-negative bacteria, 11 of Gram-positive bacteria and nine of yeasts were identified. Among 200 isolates, Gram-negative, Gram-positive bacteria and yeasts represented 11%, 27% and 62% of the total number of isolates studied. The most common genera of isolated yeasts were Hanseniaspora (37%, Metschnikowia (31%, and Rhodotorula (10%. The most frequently isolated among Gram-negative bacteria were Acinetobacter (22%, Pseudomonas (22% and Sphingomonas (13%. The most common genera of Gram-positive bacteria were Bacillus (20%, Lactobacillus (19%, Leuconostoc and Staphylococcus (11%, respectively.

  17. Marine microorganisms as potential biofactories for synthesis of metallic nanoparticles.

    Science.gov (United States)

    Manivasagan, Panchanathan; Nam, Seung Yun; Oh, Junghwan

    2016-11-01

    The use of marine microorganisms as potential biofactories for green synthesis of metallic nanoparticles is a relatively new field of research with considerable prospects. This method is eco-friendly, time saving, and inexpensive and can be easily scaled up for large-scale synthesis. The increasing need to develop simple, nontoxic, clean, and environmentally safe production methods for nanoparticles and to decrease environmental impact, minimize waste, and increase energy productivity has become important in this field. Marine microorganisms are tiny organisms that live in marine ecosystems and account for >98% of biomass of the world's ocean. Marine microorganisms synthesize metallic nanoparticles either intracellularly or extracellularly. Marine microbially-produced metallic nanoparticles have received considerable attention in recent years because of their expected impact on various applications such as medicine, energy, electronic, and space industries. The present review discusses marine microorganisms as potential biofactories for the green synthesis of metallic nanoparticles and their potential applications.

  18. New micro-organism

    Energy Technology Data Exchange (ETDEWEB)

    Takakuwa, Masayoshi; Hashimoto, Gotaro

    1987-09-12

    Invention relates with a new organism for the coal liquefying desulfurization. This micro-organism conducts a good sporulation on a culture medium which contains a coal as an only carbon source. It belongs to Penicillium and named Penicillium MT-6001 registered at Fermentation Research Institute No. 8463. Coal powder is thrown into a reaction vessel which accommodated a culture solution of this bacteria, and the surface of the solution is covered with liquid paraffin; coal powder is treated of liquefaction for about 5 hours while maintaining the anaerobic condition and slowly agitating to form a transparent solution layer on the surface of the reactor together with liquid paraffin. Liquefied product shows an analysis pattern similar to naphthenic petroleum containing a lipid with polar radical. (2 figs)

  19. Proteolysis in hyperthermophilic microorganisms

    Directory of Open Access Journals (Sweden)

    Donald E. Ward

    2002-01-01

    Full Text Available Proteases are found in every cell, where they recognize and break down unneeded or abnormal polypeptides or peptide-based nutrients within or outside the cell. Genome sequence data can be used to compare proteolytic enzyme inventories of different organisms as they relate to physiological needs for protein modification and hydrolysis. In this review, we exploit genome sequence data to compare hyperthermophilic microorganisms from the euryarchaeotal genus Pyrococcus, the crenarchaeote Sulfolobus solfataricus, and the bacterium Thermotoga maritima. An overview of the proteases in these organisms is given based on those proteases that have been characterized and on putative proteases that have been identified from genomic sequences, but have yet to be characterized. The analysis revealed both similarities and differences in the mechanisms utilized for proteolysis by each of these hyperthermophiles and indicated how these mechanisms relate to proteolysis in less thermophilic cells and organisms.

  20. Thermophilic microorganisms in biomining.

    Science.gov (United States)

    Donati, Edgardo Rubén; Castro, Camila; Urbieta, María Sofía

    2016-11-01

    Biomining is an applied biotechnology for mineral processing and metal extraction from ores and concentrates. This alternative technology for recovering metals involves the hydrometallurgical processes known as bioleaching and biooxidation where the metal is directly solubilized or released from the matrix for further solubilization, respectively. Several commercial applications of biomining can be found around the world to recover mainly copper and gold but also other metals; most of them are operating at temperatures below 40-50 °C using mesophilic and moderate thermophilic microorganisms. Although biomining offers an economically viable and cleaner option, its share of the world´s production of metals has not grown as much as it was expected, mainly considering that due to environmental restrictions in many countries smelting and roasting technologies are being eliminated. The slow rate of biomining processes is for sure the main reason of their poor implementation. In this scenario the use of thermophiles could be advantageous because higher operational temperature would increase the rate of the process and in addition it would eliminate the energy input for cooling the system (bioleaching reactions are exothermic causing a serious temperature increase in bioreactors and inside heaps that adversely affects most of the mesophilic microorganisms) and it would decrease the passivation of mineral surfaces. In the last few years many thermophilic bacteria and archaea have been isolated, characterized, and even used for extracting metals. This paper reviews the current status of biomining using thermophiles, describes the main characteristics of thermophilic biominers and discusses the future for this biotechnology.

  1. Radioresistant microorganisms and food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, H [Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment

    1976-01-01

    This paper deals with Micrococcus radiodurans, Arthrobacter radiotolerance, etc., which were isolated and discovered as radioresistant microorganisms. As for the explanation of the mechanism of radioresistance of these microorganisms, the consideration that these organisms have marked repair power of the damaged DNA and have many opportunity to repair the damaged DNA because of their long fission term were cited. The relationship between the radioresistance of microorganisms and food irradiation was also mentioned.

  2. Polysaccharides from Extremophilic Microorganisms

    Science.gov (United States)

    Nicolaus, B.; Moriello, V. Schiano; Lama, L.; Poli, A.; Gambacorta, A.

    2004-02-01

    Several marine thermophilic strains were analyzed for exopolysaccharide production. The screening process revealed that a significant number of thermophilic microorganisms were able to produce biopolymers, and some of them also revealed interesting chemical compositions. We have identified four new polysaccharides from thermophilic marine bacteria, with complex primary structures and with different repetitive units: a galacto-mannane type from strain number 4004 and mannane type for the other strains. The thermophilic Bacillus thermantarcticus produces two exocellular polysaccharides (EPS 1, EPS 2) that give the colonies a typical mucous character. The exopolysaccharide fraction was produced with all substrates assayed, although a higher yield 400 mg liter-1 was obtained with mannose as carbon and energy source. NMR spectra confirmed that EPS 1 was a heteropolysaccharide of which the repeating unit was constituted by four different α-D-mannoses and three different β-D-glucoses. It seems to be close to some xantan polymers. EPS 2 was a mannan. Four different α-D-mannoses were found as the repeating unit. Production and chemical studies of biopolymers produced by halophilic archaea, Haloarcula species were also reported.

  3. Biotechnologies for Marine Oil Spill Cleanup: Indissoluble Ties with Microorganisms

    KAUST Repository

    Mapelli, Francesca; Scoma, Alberto; Michoud, Gregoire; Aulenta, Federico; Boon, Nico; Borin, Sara; Kalogerakis, Nicolas; Daffonchio, Daniele

    2017-01-01

    The ubiquitous exploitation of petroleum hydrocarbons (HCs) has been accompanied by accidental spills and chronic pollution in marine ecosystems, including the deep ocean. Physicochemical technologies are available for oil spill cleanup, but HCs must ultimately be mineralized by microorganisms. How environmental factors drive the assembly and activity of HC-degrading microbial communities remains unknown, limiting our capacity to integrate microorganism-based cleanup strategies with current physicochemical remediation technologies. In this review, we summarize recent findings about microbial physiology, metabolism and ecology and describe how microbes can be exploited to create improved biotechnological solutions to clean up marine surface and deep waters, sediments and beaches.

  4. Biotechnologies for Marine Oil Spill Cleanup: Indissoluble Ties with Microorganisms

    KAUST Repository

    Mapelli, Francesca

    2017-05-13

    The ubiquitous exploitation of petroleum hydrocarbons (HCs) has been accompanied by accidental spills and chronic pollution in marine ecosystems, including the deep ocean. Physicochemical technologies are available for oil spill cleanup, but HCs must ultimately be mineralized by microorganisms. How environmental factors drive the assembly and activity of HC-degrading microbial communities remains unknown, limiting our capacity to integrate microorganism-based cleanup strategies with current physicochemical remediation technologies. In this review, we summarize recent findings about microbial physiology, metabolism and ecology and describe how microbes can be exploited to create improved biotechnological solutions to clean up marine surface and deep waters, sediments and beaches.

  5. Identification and Characterization of Extremophile Microorganisms with Significance to Astrobiology

    Science.gov (United States)

    Bej, Asim K.

    2003-01-01

    It is now well recognized that microorganisms thrive in extreme ecological conditions such as geothermal vents, polar region, acid and alkaline lakes, and the cold pressurized depth of the ocean floor of this planet. Morphological, physiological, biochemical and genetic adaptations to extreme environments by these extremophile microorganisms have generated immense interest amongst astrobiologists who increasingly believe in the existence of extraterrestrial life. The evidence collected by NASA's space probe Galileo suggested the presence of liquid water and volcanic activity on Mars and Jupiter's satellite Europa. Volcanic activity provides some of the heat necessary to keep the water on Europa from freezing that could provide important dissolved chemicals needed by living organisms. The possibility of the existence of hypersaline alkaline lakes and evaporites confined within closed volcanic basins and impact craters on Mars, and a layer of liquid water under the ice on Europa provide sufficient 'raison d'etre' to study microorganisms in similar extreme environments on Earth, which could provide us with a model that would help establish the existence of extraterrestrial life on other planetary bodies. The objectives of the summer research project were as follows: (1) application of molecular approaches to help establish new species of extremophile microorganisms isolated from a hypersaline alkaline lake; and (2) identification of a major cold-shock gene (cspA) homolog from a psychrotolerant microorganism, PmagG1.

  6. Biofuel production by recombinant microorganisms

    Science.gov (United States)

    Liao, James C.; Atsumi, Shota; Cann, Anthony F.

    2017-07-04

    Provided herein are metabolically-modified microorganisms useful for producing biofuels. More specifically, provided herein are methods of producing high alcohols including isobutanol, 1-butanol, 1-propanol, 2-methyl-1-butanol, 3-methyl-1-butanol and 2-phenylethanol from a suitable substrate.

  7. Airborne microorganisms from waste containers.

    Science.gov (United States)

    Jedlicka, Sabrina S; Stravitz, David M; Lyman, Charles E

    2012-01-01

    In physician's offices and biomedical labs, biological waste is handled every day. This waste is disposed of in waste containers designed for holding red autoclave bags. The containers used in these environments are closed hands-free containers, often with a step pedal. While these containers protect the user from surface-borne microorganisms, the containers may allow airborne microorganisms to escape via the open/close mechanism because of the air current produced upon open/close cycles. In this study, the air current was shown to be sufficient to allow airborne escape of microorganisms held in the container, including Aspergillus niger. However, bacterial cultures, such as Escherichia coli and Lactococcus lactis did not escape. This may be due to the choice of bacterial cultures and the absence of solid waste, such as dust or other particulate matter in the waste containers, that such strains of bacteria could travel on during aerosolization. We compared these results to those obtained using a re-designed receptacle, which mimimizes air currents, and detected no escaping microorganisms. This study highlights one potential source of airborne contamination in labs, hospitals, and other environments that dispose of biological waste.

  8. Temperature induced changes in the heterocyst glycolipid composition of N2-fixing heterocystous cyanobacteria

    NARCIS (Netherlands)

    Bauersachs, T.; Stal, L.J.; Grego, M.; Schwark, L.

    2014-01-01

    We investigated the effect of temperature on the heterocyst glycolipid (HG) composition of the diazotrophic heterocystous cyanobacteria Anabaena sp. strain CCY9613 and Nostoc sp. strain CCY9926 grown at 9, 12, 16, 20 and 24 °C. Both strains contained an overall similar composition of heterocyst

  9. Rapid synthesis and metabolism of glutamate in N2-fixing bacteroids

    International Nuclear Information System (INIS)

    Salminen, S.O.; Streeter, J.G.

    1987-01-01

    Symbiotic nodule bacteroids are thought to support N 2 fixation mainly by metabolizing dicarboxylic acids to CO 2 , generating reductant and ATP required by nitrogenase. Bradyrhizobium japonicum bacteroids were isolated anaerobically and incubated at 2% O 2 with 14 C-labeled succinate, malate, glutamate, or aspartate. 14 CO 2 was collected, and the bacteroid contents separated into neutral, organic acid, and amino acid fractions. The respiration of substrates, relative to their uptake, was malate > glutamate > succinate > aspartate. Analysis of the fractions revealed that will all substrates the radioactivity was found mostly in the amino acid fraction. The labeling of the neutral fraction was negligible and only a small amount of label was found in the organic acid fraction indicating a small pool size. TLC of the amino acid fraction showed the label to be principally in glutamate. Glutamate contained 67, 80, 97, and 88% of the 14 C in the amino acid fraction in bacteroids fed with succinate, malate, glutamate and aspartate, respectively. The data suggest that glutamate may play an important role in the bacteroid function

  10. Unique thylakoid membrane architecture of a unicellular N2-fixing cyanobacterium revealed by electron tomography

    Energy Technology Data Exchange (ETDEWEB)

    Liberton, Michelle; Austin II, Jotham R; Berg, R. Howard; Pakrasi, Himadri B

    2011-04-01

    Cyanobacteria, descendants of the endosymbiont that gave rise to modern-day chloroplasts, are vital contributors to global biological energy conversion processes. A thorough understanding of the physiology of cyanobacteria requires detailed knowledge of these organisms at the level of cellular architecture and organization. In these prokaryotes, the large membrane protein complexes of the photosynthetic and respiratory electron transport chains function in the intracellular thylakoid membranes. Like plants, the architecture of the thylakoid membranes in cyanobacteria has direct impact on cellular bioenergetics, protein transport, and molecular trafficking. However, whole-cell thylakoid organization in cyanobacteria is not well understood. Here we present, by using electron tomography, an in-depth analysis of the architecture of the thylakoid membranes in a unicellular cyanobacterium, Cyanothece sp. ATCC 51142. Based on the results of three-dimensional tomographic reconstructions of near-entire cells, we determined that the thylakoids in Cyanothece 51142 form a dense and complex network that extends throughout the entire cell. This thylakoid membrane network is formed from the branching and splitting of membranes and encloses a single lumenal space. The entire thylakoid network spirals as a peripheral ring of membranes around the cell, an organization that has not previously been described in a cyanobacterium. Within the thylakoid membrane network are areas of quasi-helical arrangement with similarities to the thylakoid membrane system in chloroplasts. This cyanobacterial thylakoid arrangement is an efficient means of packing a large volume of membranes in the cell while optimizing intracellular transport and trafficking.

  11. Unique Thylakoid Membrane Architecture of a Unicellular N2-Fixing Cyanobacterium Revealed by Electron Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Liberton, Michelle L.; Austin, Jotham R.; Berg, R. H.; Pakrasi, Himadri B.

    2011-04-01

    Cyanobacteria, descendants of the endosymbiont that gave rise to modern-day chloroplasts, are vital contributors to global biological energy conversion processes. A thorough understanding of the physiology of cyanobacteria requires detailed knowledge of these organisms at the level of cellular architecture and organization. In these prokaryotes, the large membrane protein complexes of the photosynthetic and respiratory electron transport chains function in the intracellular thylakoid membranes. Like plants, the architecture of the thylakoid membranes in cyanobacteria has direct impact on cellular bioenergetics, protein transport, and molecular trafficking. However, whole-cell thylakoid organization in cyanobacteria is not well understood. Here we present, by using electron tomography, an in-depth analysis of the architecture of the thylakoid membranes in a unicellular cyanobacterium, Cyanothece sp. ATCC 51142. Based on the results of three-dimensional tomographic reconstructions of near-entire cells, we determined that the thylakoids in Cyanothece 51142 form a dense and complex network that extends throughout the entire cell. This thylakoid membrane network is formed from the branching and splitting of membranes and encloses a single lumenal space. The entire thylakoid network spirals as a peripheral ring of membranes around the cell, an organization that has not previously been described in a cyanobacterium. Within the thylakoid membrane network are areas of quasi-helical arrangement with similarities to the thylakoid membrane system in chloroplasts. This cyanobacterial thylakoid arrangement is an efficient means of packing a large volume of membranes in the cell while optimizing intracellular transport and trafficking.

  12. Genomic resources for identification of the minimal N2 -fixing symbiotic genome.

    Science.gov (United States)

    diCenzo, George C; Zamani, Maryam; Milunovic, Branislava; Finan, Turlough M

    2016-09-01

    The lack of an appropriate genomic platform has precluded the use of gain-of-function approaches to study the rhizobium-legume symbiosis, preventing the establishment of the genes necessary and sufficient for symbiotic nitrogen fixation (SNF) and potentially hindering synthetic biology approaches aimed at engineering this process. Here, we describe the development of an appropriate system by reverse engineering Sinorhizobium meliloti. Using a novel in vivo cloning procedure, the engA-tRNA-rmlC (ETR) region, essential for cell viability and symbiosis, was transferred from Sinorhizobium fredii to the ancestral location on the S. meliloti chromosome, rendering the ETR region on pSymB redundant. A derivative of this strain lacking both the large symbiotic replicons (pSymA and pSymB) was constructed. Transfer of pSymA and pSymB back into this strain restored symbiotic capabilities with alfalfa. To delineate the location of the single-copy genes essential for SNF on these replicons, we screened a S. meliloti deletion library, representing > 95% of the 2900 genes of the symbiotic replicons, for their phenotypes with alfalfa. Only four loci, accounting for < 12% of pSymA and pSymB, were essential for SNF. These regions will serve as our preliminary target of the minimal set of horizontally acquired genes necessary and sufficient for SNF. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  13. Effect of neem cake/fertilizers on symbiotic and non-symbiotic N2 fixing bacteria

    International Nuclear Information System (INIS)

    Akhtar, S.; Solangi, A.H.; Gilani, G.; Pirzada, M.H.

    2002-01-01

    Neem cake amendment in soil at 1.3% no adverse effect on the population of four symbiotic Rhizobium species viz., japonicum, R. leguminosarum, R. Phaseoli and R. Fredii and three non-symbiotic free living nitrogen fixers bacteria viz., Pseudomonas diazotrophicus, Klebsiella planticola and Enterobacter cloacae. Neem cake extracted with n-hexane stimulated the growth of Rhizobium species in vitro, whereas Neem cake expeller extracted neither inhibited nor stimulated the growth of Rhizobium species except for R. Fredii, whose was slightly retarded. The fertilizers (urea, NPK and DAP) had no adverse effect on these bacteria even at the dosage ten times higher the recommended dose. (author)

  14. Microorganisms .

    African Journals Online (AJOL)

    ) and heat/pH-shift treatments. This technique resulted in 47% enzyme yield with a purification fac- tor of 12. Technique II which involved two extraction steps by' aqueous two - phase system. (APS) coupled with UF resulted in 62 % enzyme ...

  15. Microorganism Utilization for Synthetic Milk

    Science.gov (United States)

    Morford, Megan A.; Khodadad, Christina L.; Caro, Janicce I.; Spencer, LaShelle E.; Richards, Jeffery T.; Strayer, Richard F.; Birmele, Michele N.; Wheeler, Raymond M.

    2014-01-01

    A desired architecture for long duration spaceflight, like aboard the International Space Station or for future missions to Mars, is to provide a supply of fresh food crops for the astronauts. However, some crops can create a high proportion of inedible plant waste. The main goal of the Synthetic Biology project, Cow in a Column, was to produce the components of milk (sugar, lipid, protein) from inedible plant waste by utilizing microorganisms (fungi, yeast, bacteria). Of particular interest was utilizing the valuable polysaccharide, cellulose, found in plant waste, to naturally fuel-through microorganism cellular metabolism- the creation of sugar (glucose), lipid (milk fat), and protein (casein) in order to produce a synthetic edible food product. Environmental conditions such as pH, temperature, carbon source, aeration, and choice microorganisms were optimized in the laboratory and the desired end-products, sugars and lipids, were analyzed. Trichoderma reesei, a known cellulolytic fungus, was utilized to drive the production of glucose, with the intent that the produced glucose would serve as the carbon source for milk fat production and be a substitute for the milk sugar lactose. Lipid production would be carried out by Rhodosporidium toruloides, yeast known to accumulate those lipids that are typically found in milk fat. Results showed that glucose and total lipid content were below what was expected during this phase of experimentation. In addition, individual analysis of six fatty acids revealed that the percentage of each fatty acid was lower than naturally produced bovine milk. Overall, this research indicates that microorganisms could be utilized to breakdown inedible solid waste to produce useable products. For future work, the production of the casein protein for milk would require the development of a genetically modified organism, which was beyond the scope of the original project. Additional trials would be needed to further refine the required

  16. The useful micro-organism

    International Nuclear Information System (INIS)

    1970-01-01

    Can man survive civilization? Academician Ivan Malek, Director of the Institute of Microbiology in Prague, a member of the Agency's Scientific Advisory Committee and for many years an adviser to the Food and Agriculture Organization, the World Health Organization and UNESCO, believes he can, But he also considers that if man is to survive he must study and use all the resources at his disposal - including the micro-organisms of the planet earth. (author)

  17. Secondary metabolites from marine microorganisms.

    Science.gov (United States)

    Kelecom, Alphonse

    2002-03-01

    After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  18. Secondary metabolites from marine microorganisms

    Directory of Open Access Journals (Sweden)

    KELECOM ALPHONSE

    2002-01-01

    Full Text Available After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  19. PROBIOTICS BASED ON TRANSGENIC MICROORGANISMS

    Directory of Open Access Journals (Sweden)

    S. А. Starovoitova

    2012-02-01

    Full Text Available Modern tendencies of recombinant microorganisms creation for obtaining on their basis a new effective biopreparations (probiotics with wider spectrum of biological and therapeutic properties were considered. A lot of attention was focused on the main genera of perspective bacteria for creation of recombinant probiotics particularly: Lactococcus, Bifidobac terium,Bacillus, Escherichia. The main created Ukrainian and foreign gene-modified strains, that are widely used today in creation of effective recombinant biopreparations were characterized. Some fundamental directions and methods of gene-modified strains obtaining, which are used in getting effective biopreparations that used for therapy and prophylactic illness were reported, under which this group of pharmaceutical drugs were not used earlier. The safety matters of probiotics using on basis of genemodified strains were examined. Medical and veterinary biopreparations on basis of recombinant microorganisms could be used directly and effectively for therapy and prophylaxis of different illness, beginning from disbacteriosis up to cardiovascular diseases. It is related with some probiotic microorganisms ability for lowering of serum cholesterol at the host organism.

  20. Microorganisms as sources of oils

    Directory of Open Access Journals (Sweden)

    Thevenieau France

    2013-11-01

    Full Text Available A number of microorganism belonging to the genera of yeast, fungi, bacteria and microalgae have ability to accumulate substantial amounts of oil, sometimes up to an even in excess of 70% of their biomass weight under specific cultivation conditions. For nearly 100 years, the commercial opportunities of using microorganisms as sources of oils have been continuously examined. Although it was evident that microbial oils could never compete commercially with the major commodity plant oils, there were commercially opportunities for the production of some of the higher valued oils. Today, with the great progress of metabolic and genetic engineering, the developments are focus on the high value oils containing important polyunsaturated or specific fatty acids. Such oils have the potential to be used in different applications area as food, feed and oleochemistry. This review is covering the related researches about different oleaginous microorganisms for lipids production and microbial oils biosynthesis process. In add, the lipid metabolism, metabolic engineering strategies to increase lipid production and the economics of microbial oils production are introduced.

  1. Transformation of the insecticide teflubenzuron by microorganisms

    NARCIS (Netherlands)

    Finkelstein, Z.I.; Baskunov, B.P.; Rietjens, I.M.C.M.; Boersma, M.G.; Vervoort, J.; Golovleva, L.A.

    2001-01-01

    Transformation of teflubenzuron, the active component in the insecticide commercialized as Nomolt, by soil microorganisms was studied. It was shown that microorganisms, belonging to Bacillus, Alcaligenes, Pseudomonas and Acinetobacter genera are capable to perform the hydrolytic cleavage of the

  2. Ocean currents generate large footprints in marine palaeoclimate proxies

    NARCIS (Netherlands)

    van Sebille, E.; Scussolini, P.; Durgadoo, J.V.; Peeters, F.J.C.; Biastoch, A.; Weijer, W.; Turney, C.; Paris, C.B.; Zahn, R.

    2015-01-01

    Fossils of marine microorganisms such as planktic foraminifera are among the cornerstones of palaeoclimatological studies. It is often assumed that the proxies derived from their shells represent ocean conditions above the location where they were deposited. Planktic foraminifera, however, are

  3. 40 CFR 725.85 - Microorganism identity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Microorganism identity. 725.85 Section... to Information § 725.85 Microorganism identity. (a) Claims applicable to the period prior to... specific microorganism identity at the time of submission of the information. This claim will apply only to...

  4. Ocean Acidification | Smithsonian Ocean Portal

    Science.gov (United States)

    Natural History Blog For Educators At The Museum Media Archive Ocean Life & Ecosystems Mammals Sharks Mangroves Poles Census of Marine Life Planet Ocean Tides & Currents Waves & Storms The Seafloor ocean is affected. Such a relatively quick change in ocean chemistry doesn't give marine life, which

  5. Effects of Atrazine on Soil Microorganisms

    Directory of Open Access Journals (Sweden)

    Ljiljana Radivojević

    2006-01-01

    Full Text Available Effects of the herbicide atrazine on soil microorganisms was investigated. Trials were set up in laboratory, on a clay loam soil. Atrazine was applied at 8.0, 40.0 and 80.0 mg/kg soil rates. The abundance of total microorganisms, fungi, actinomycetes, cellulolytic microorganisms and amino-heterotrophs was recorded. Soil samples were collected 1, 7, 14, 21, 30 and 60 days after atrazine treatment for microbiological analyses.The results showed that the intensity of atrazine effect on soil microorganisms depended on treatment rate, exposure time and group of microorganisms. Atrazine had an inhibiting effect on cellulolytic microorganisms and amino-heterotrophs. Initially, it inhibited fungiand actinomycetes but its effect turned into a stimulating one once a population recovered. Atrazine had a stimulating effect on total abundance of microorganisms.

  6. Ocean tides

    Science.gov (United States)

    Hendershott, M. C.

    1975-01-01

    A review of recent developments in the study of ocean tides and related phenomena is presented. Topics briefly discussed include: the mechanism by which tidal dissipation occurs; continental shelf, marginal sea, and baroclinic tides; estimation of the amount of energy stored in the tide; the distribution of energy over the ocean; the resonant frequencies and Q factors of oceanic normal modes; the relationship of earth tides and ocean tides; and numerical global tidal models.

  7. Development of Novel Drugs from Marine Surface Associated Microorganisms

    Directory of Open Access Journals (Sweden)

    Suhelen Egan

    2010-03-01

    Full Text Available While the oceans cover more than 70% of the Earth’s surface, marine derived microbial natural products have been largely unexplored. The marine environment is a habitat for many unique microorganisms, which produce biologically active compounds (“bioactives” to adapt to particular environmental conditions. For example, marine surface associated microorganisms have proven to be a rich source for novel bioactives because of the necessity to evolve allelochemicals capable of protecting the producer from the fierce competition that exists between microorganisms on the surfaces of marine eukaryotes. Chemically driven interactions are also important for the establishment of cross-relationships between microbes and their eukaryotic hosts, in which organisms producing antimicrobial compounds (“antimicrobials”, may protect the host surface against over colonisation in return for a nutrient rich environment. As is the case for bioactive discovery in general, progress in the detection and characterization of marine microbial bioactives has been limited by a number of obstacles, such as unsuitable culture conditions, laborious purification processes, and a lack of de-replication. However many of these limitations are now being overcome due to improved microbial cultivation techniques, microbial (meta- genomic analysis and novel sensitive analytical tools for structural elucidation. Here we discuss how these technical advances, together with a better understanding of microbial and chemical ecology, will inevitably translate into an increase in the discovery and development of novel drugs from marine microbial sources in the future.

  8. Study of radioresistance of microorganisms

    International Nuclear Information System (INIS)

    Olbrichova, D.

    1983-01-01

    Strain radiosensitivity was evaluated on the basis of the determination of inactivation curve parameters and the determination of the D 10 value. The course of curves was investigated for two 60 Co sources, RCHM-gamma-20 (USSR) with an activity of 2.54x10 14 Bq and AECL (type J-6000, Canada) with an activity of 4.92x10 16 Bq. The curve parameters were determined for microorganisms in buffer medium and for cultures in dehydrated condition. Coccus germs were irradiated with doses of 1, 2, 3, 4, 5 and 6 kGy and aerobic sporulates with doses of 3, 6, 9, 12 and 15 kGy. For comparing the resistance of isolated strains the t-test was used. The most resistant of the isolated strains were Bacillus cereus, Bacillus subtilis, Bacillus pumilus and Bacillus megatherium. (E.S.)

  9. Functional Basis of Microorganism Classification.

    Science.gov (United States)

    Zhu, Chengsheng; Delmont, Tom O; Vogel, Timothy M; Bromberg, Yana

    2015-08-01

    Correctly identifying nearest "neighbors" of a given microorganism is important in industrial and clinical applications where close relationships imply similar treatment. Microbial classification based on similarity of physiological and genetic organism traits (polyphasic similarity) is experimentally difficult and, arguably, subjective. Evolutionary relatedness, inferred from phylogenetic markers, facilitates classification but does not guarantee functional identity between members of the same taxon or lack of similarity between different taxa. Using over thirteen hundred sequenced bacterial genomes, we built a novel function-based microorganism classification scheme, functional-repertoire similarity-based organism network (FuSiON; flattened to fusion). Our scheme is phenetic, based on a network of quantitatively defined organism relationships across the known prokaryotic space. It correlates significantly with the current taxonomy, but the observed discrepancies reveal both (1) the inconsistency of functional diversity levels among different taxa and (2) an (unsurprising) bias towards prioritizing, for classification purposes, relatively minor traits of particular interest to humans. Our dynamic network-based organism classification is independent of the arbitrary pairwise organism similarity cut-offs traditionally applied to establish taxonomic identity. Instead, it reveals natural, functionally defined organism groupings and is thus robust in handling organism diversity. Additionally, fusion can use organism meta-data to highlight the specific environmental factors that drive microbial diversification. Our approach provides a complementary view to cladistic assignments and holds important clues for further exploration of microbial lifestyles. Fusion is a more practical fit for biomedical, industrial, and ecological applications, as many of these rely on understanding the functional capabilities of the microbes in their environment and are less concerned with

  10. Functional Basis of Microorganism Classification

    Science.gov (United States)

    Zhu, Chengsheng; Delmont, Tom O.; Vogel, Timothy M.; Bromberg, Yana

    2015-01-01

    Correctly identifying nearest “neighbors” of a given microorganism is important in industrial and clinical applications where close relationships imply similar treatment. Microbial classification based on similarity of physiological and genetic organism traits (polyphasic similarity) is experimentally difficult and, arguably, subjective. Evolutionary relatedness, inferred from phylogenetic markers, facilitates classification but does not guarantee functional identity between members of the same taxon or lack of similarity between different taxa. Using over thirteen hundred sequenced bacterial genomes, we built a novel function-based microorganism classification scheme, functional-repertoire similarity-based organism network (FuSiON; flattened to fusion). Our scheme is phenetic, based on a network of quantitatively defined organism relationships across the known prokaryotic space. It correlates significantly with the current taxonomy, but the observed discrepancies reveal both (1) the inconsistency of functional diversity levels among different taxa and (2) an (unsurprising) bias towards prioritizing, for classification purposes, relatively minor traits of particular interest to humans. Our dynamic network-based organism classification is independent of the arbitrary pairwise organism similarity cut-offs traditionally applied to establish taxonomic identity. Instead, it reveals natural, functionally defined organism groupings and is thus robust in handling organism diversity. Additionally, fusion can use organism meta-data to highlight the specific environmental factors that drive microbial diversification. Our approach provides a complementary view to cladistic assignments and holds important clues for further exploration of microbial lifestyles. Fusion is a more practical fit for biomedical, industrial, and ecological applications, as many of these rely on understanding the functional capabilities of the microbes in their environment and are less concerned

  11. Five decades of N2 fixation research in the North Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    Mar eBenavides

    2015-06-01

    Full Text Available Dinitrogen (N2 fixation (the reduction of atmospheric N2 to ammonium by specialized prokaryotic microbes, represents an important input of fixed nitrogen and contributes significantly to primary productivity in the oceans. Marine N2 fixation was discovered in the North Atlantic Ocean (NA in the 1960s. Ever since, the NA has been subject to numerous studies that have looked into the diversity and abundance of N2-fixing microbes (diazotrophs, the spatial and temporal variability of N2 fixation rates, and the range of physical and chemical variables that control them. The NA provides 10-25% of the globally fixed N2, ranking as the third basin with the largest N2 fixation inputs in the world’s oceans. This basin suffers a chronic depletion in phosphorus availability, more aeolian dust deposition than any other basin in the world’s oceans, and significant nutrient inputs from important rivers like the Amazon and the Congo. These characteristics make it unique in comparison with other oceanic basins. After five decades of intensive research, here we present a comprehensive review of our current understanding of diazotrophic activity in the NA from both a geochemical and biological perspective. We discuss the advantages and disadvantages of current methods, future perspectives, and questions which remain to be answered.

  12. Oceanic archipelagos

    DEFF Research Database (Denmark)

    Triantis, Kostas A.; Whittaker, Robert James; Fernández-Palacios, José María

    2016-01-01

    Since the contributions of Charles Darwin and Alfred Russel Wallace, oceanic archipelagos have played a central role in the development of biogeography. However, despite the critical influence of oceanic islands on ecological and evolutionary theory, our focus has remained limited to either the i...... of the archipelagic geological dynamics that can affect diversity at both the island and the archipelagic level. We also reaffirm that oceanic archipelagos are appropriate spatiotemporal units to frame analyses in order to understand large scale patterns of biodiversity....

  13. Effective Microorganisms: Myth or reality?

    Directory of Open Access Journals (Sweden)

    Aníbal F. Cóndor_Golec

    2013-04-01

    Full Text Available Th e increase in population has lead to intensifi cation of agricultural systems. Due to the use of pesticides the productivity of agricultural systems has increased but environmental deterioration and unsustainable systems are the consequences of these ways of management. Th e environmentally friendly Eff ective Microorganisms (EM technology claims an enormous amount of benefi ts (claimed by the companies. Th e use of EM as an addictive to manure or as a spray directly in the fi elds may increase the microfauna diversity of the soil and many benefi ts are derived from that increase. It seems that suffi cient information is available about this new technology. Th e aim of this project is to make an analysis of the literature about EM and answer the following questions: 1 how much is known about EM?, 2 how much research is done on EM?, 3 what are the principals of EM?, what are the socio-economic implications of EM?. We want to answer these questions in order to publish the facts about EM and its socio-economic implications.

  14. Systems Biology of Industrial Microorganisms

    Science.gov (United States)

    Papini, Marta; Salazar, Margarita; Nielsen, Jens

    The field of industrial biotechnology is expanding rapidly as the chemical industry is looking towards more sustainable production of chemicals that can be used as fuels or building blocks for production of solvents and materials. In connection with the development of sustainable bioprocesses, it is a major challenge to design and develop efficient cell factories that can ensure cost efficient conversion of the raw material into the chemical of interest. This is achieved through metabolic engineering, where the metabolism of the cell factory is engineered such that there is an efficient conversion of sugars, the typical raw materials in the fermentation industry, into the desired product. However, engineering of cellular metabolism is often challenging due to the complex regulation that has evolved in connection with adaptation of the different microorganisms to their ecological niches. In order to map these regulatory structures and further de-regulate them, as well as identify ingenious metabolic engineering strategies that full-fill mass balance constraints, tools from systems biology can be applied. This involves both high-throughput analysis tools like transcriptome, proteome and metabolome analysis, as well as the use of mathematical modeling to simulate the phenotypes resulting from the different metabolic engineering strategies. It is in fact expected that systems biology may substantially improve the process of cell factory development, and we therefore propose the term Industrial Systems Biology for how systems biology will enhance the development of industrial biotechnology for sustainable chemical production.

  15. [Genome editing of industrial microorganism].

    Science.gov (United States)

    Zhu, Linjiang; Li, Qi

    2015-03-01

    Genome editing is defined as highly-effective and precise modification of cellular genome in a large scale. In recent years, such genome-editing methods have been rapidly developed in the field of industrial strain improvement. The quickly-updating methods thoroughly change the old mode of inefficient genetic modification, which is "one modification, one selection marker, and one target site". Highly-effective modification mode in genome editing have been developed including simultaneous modification of multiplex genes, highly-effective insertion, replacement, and deletion of target genes in the genome scale, cut-paste of a large DNA fragment. These new tools for microbial genome editing will certainly be applied widely, and increase the efficiency of industrial strain improvement, and promote the revolution of traditional fermentation industry and rapid development of novel industrial biotechnology like production of biofuel and biomaterial. The technological principle of these genome-editing methods and their applications were summarized in this review, which can benefit engineering and construction of industrial microorganism.

  16. Ocean transportation

    National Research Council Canada - National Science Library

    Frankel, Ernst G; Marcus, Henry S

    1973-01-01

    .... This analysis starts with a review of ocean transportation demand and supply including projections of ship capacity demand and world shipbuilding capacity under various economic and political assumptions...

  17. Biofouling of marbles by oxygenic photosynthetic microorganisms.

    Science.gov (United States)

    Karaca, Zeki; Öztürk, Ayten; Çolak, Emel

    2015-08-01

    Phototrophic microorganisms disfigure the surfaces of different types of stone. Stone structure is damaged by the activity of photoautotrophic and other microorganisms. However, to date few, investigations have been undertaken into the relationship between microorganisms and the properties of different types of marble. In this study, biological activity of photoautotrophic microorganisms on three types of marble (Yatagan White, Giallo Anticato and Afyon White) was investigated under laboratory conditions over a short period of time. The three types of marble supported the growth of phototrophic microbial communities on their outer and inner layers, turning their original colour from white to a yellowish green colour. The porosity of the marble types facilitated filamentous microbial growth in the presence of water. Scanning electron microscope analysis revealed the accumulation of aggregates such as small spherical, fibrillar, calcified globular bodies on the inner surfaces of the marbles. This suggests that the microscopic characteristics of particular marble types may stimulate the growth of certain types of microorganisms.

  18. Ocean technology

    Digital Repository Service at National Institute of Oceanography (India)

    Peshwe, V.B.

    stream_size 2 stream_content_type text/plain stream_name Voices_Oceans_1996_113.pdf.txt stream_source_info Voices_Oceans_1996_113.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  19. Ocean acidification

    National Research Council Canada - National Science Library

    Gattuso, J.P; Hansson, L

    2011-01-01

    The fate of much of the CO 2 we produce will be to enter the ocean. In a sense, we are fortunate that ocean water is endowed with the capacity to absorb far more CO 2 per litre than were it salt free...

  20. Decomposition of diesel oil by various microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Suess, A; Netzsch-Lehner, A

    1969-01-01

    Previous experiments demonstrated the decomposition of diesel oil in different soils. In this experiment the decomposition of /sup 14/C-n-Hexadecane labelled diesel oil by special microorganisms was studied. The results were as follows: (1) In the experimental soils the microorganisms Mycoccus ruber, Mycobacterium luteum and Trichoderma hamatum are responsible for the diesel oil decomposition. (2) By adding microorganisms to the soil an increase of the decomposition rate was found only in the beginning of the experiments. (3) Maximum decomposition of diesel oil was reached 2-3 weeks after incubation.

  1. Ocean energy

    International Nuclear Information System (INIS)

    2006-01-01

    This annual evaluation is a synthesis of works published in 2006. Comparisons are presented between the wind power performances and European Commission White Paper and Biomass action plan objectives. The sector covers the energy exploitation of all energy flows specifically supplied by the seas and oceans. At present, most efforts in both research and development and in experimental implementation are concentrated on tidal currents and wave power. 90% of today worldwide ocean energy production is represented by a single site: the Rance Tidal Power Plant. Ocean energies must face up two challenges: progress has to be made in finalizing and perfecting technologies and costs must be brought under control. (A.L.B.)

  2. Tapping uncultured microorganisms through metagenomics for drug ...

    African Journals Online (AJOL)

    African Journal of Biotechnology ... Microorganisms are major source of bioactive natural products, and several ... This review highlights the recent methodologies, limitations, and applications of metagenomics for the discovery of new drugs.

  3. Detection of extracellular enzymatic activity in microorganisms ...

    African Journals Online (AJOL)

    sunny t

    2015-09-18

    Sep 18, 2015 ... microorganisms with all three enzymatic activities, thereby establishing these techniques as ... supplemented at 1% with vegetable oils, including olive (OLI) ..... cepacia lipase for biodiesel fuel production from soybean oil.

  4. Microorganisms' mediated reduction of β-ketoesters

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-20

    Oct 20, 2008 ... Whole cells usually express a multitude of enzymatic activities; therefore an ... Each microorganism was cultivated for the biomass development on specific medium ..... Ketoester reductase for conversion of keto acid esters to ...

  5. Detection of extracellular enzymatic activity in microorganisms ...

    African Journals Online (AJOL)

    Detection of extracellular enzymatic activity in microorganisms isolated from waste vegetable oil contaminated soil using plate methodologies. Eugenia G. Ortiz Lechuga, Isela Quintero Zapata, Katiushka Arévalo Niño ...

  6. Defensive properties of pyrrolizidine alkaloids against microorganisms

    NARCIS (Netherlands)

    Joosten, L.; Van Veen, J.A.

    2011-01-01

    The understanding of the selection factors that drive chemical diversification of secondary metabolites of constitutive defence systems in plants, such as pyrrolizidine alkaloids (PAs), is still incomplete. Historically, plants always have been confronted with microorganisms. Long before herbivores

  7. Genetic fingerprint of microorganisms associated with the ...

    Indian Academy of Sciences (India)

    inviting range of elements which microorganisms use in their ... ization and degradation of organic binders leading to struc- tural damage (Herrera et al. 2004). Microbial solubilization of materials involves the produc- ... architectural cement.

  8. Mechanisms of nickel toxicity in microorganisms

    OpenAIRE

    Macomber, Lee; Hausinger, Robert P.

    2011-01-01

    Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological co...

  9. Pathogenic and opportunistic microorganisms in caves

    Directory of Open Access Journals (Sweden)

    Sanchez-Moral Sergio

    2010-01-01

    Full Text Available With today’s leisure tourism, the frequency of visits to many caves makes it necessary to know about possible potentially pathogenic microorganisms in caves, determine their reservoirs, and inform the public about the consequences of such visits. Our data reveal that caves could be a potential danger to visitors because of the presence of opportunistic microorganisms, whose existence and possible development in humans is currently unknown.

  10. Ocean Acidification

    Science.gov (United States)

    Ocean and coastal acidification is an emerging issue caused by increasing amounts of carbon dioxide being absorbed by seawater. Changing seawater chemistry impacts marine life, ecosystem services, and humans. Learn what EPA is doing and what you can do.

  11. Ocean transportation

    National Research Council Canada - National Science Library

    Frankel, Ernst G; Marcus, Henry S

    1973-01-01

    .... The discussion of technology considers the ocean transportation system as a whole, and the composite subsystems such as hull, outfit, propulsion, cargo handling, automation, and control and interface technology...

  12. Ocean transportation

    National Research Council Canada - National Science Library

    Frankel, Ernst G; Marcus, Henry S

    1973-01-01

    .... In ocean transportation economics we present investment and operating costs as well as the results of a study of financing of shipping. Similarly, a discussion of government aid to shipping is presented.

  13. Ocean Color

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite-derived Ocean Color Data sets from historical and currently operational NASA and International Satellite missions including the NASA Coastal Zone Color...

  14. Ocean Quality

    OpenAIRE

    Brevik, Roy Schjølberg; Jordheim, Nikolai; Martinsen, John Christian; Labori, Aleksander; Torjul, Aleksander Lelis

    2017-01-01

    Bacheloroppgave i Internasjonal Markedsføring fra ESADE i Spania, 2017 In this thesis we were going to answer the problem definition “which segments in the Spanish market should Ocean Quality target”. By doing so we started to collect data from secondary sources in order to find information about the industry Ocean Quality are operating in. After conducting the secondary research, we still lacked essential information about the existing competition in the aquaculture industry o...

  15. Advancing Ocean Monitoring Near Coral Reefs

    Science.gov (United States)

    Heron, Scott F.; Steinberg, Craig R.; Heron, Mal L.; Mantovanelli, Alessandra; Jaffrés, Jasmine B. D.; Skirving, William J.; McAllister, Felicity; Rigby, Paul; Wisdom, Daniel; Bainbridge, Scott

    2010-10-01

    Corals, the foundation of tropical marine ecosystems, exist in a symbiotic relationship with zooxanthellae (algae). The corals obtain much of their energy by consuming compounds derived from photosynthesis by these microorganisms; the microorganisms, which reside in the coral tissue, in turn use waste products from the corals to sustain photosynthesis. This symbiosis is very sensitive to subtle changes in environment, such as increased ocean acidity, temperature, and light. When unduly stressed, the colorful algae are expelled from the corals, causing the corals to “bleach” and potentially die [e.g., van Oppen and Lough, 2009].

  16. Functional microorganisms for functional food quality.

    Science.gov (United States)

    Gobbetti, M; Cagno, R Di; De Angelis, M

    2010-09-01

    Functional microorganisms and health benefits represent a binomial with great potential for fermented functional foods. The health benefits of fermented functional foods are expressed either directly through the interactions of ingested live microorganisms with the host (probiotic effect) or indirectly as the result of the ingestion of microbial metabolites synthesized during fermentation (biogenic effect). Since the importance of high viability for probiotic effect, two major options are currently pursued for improving it--to enhance bacterial stress response and to use alternative products for incorporating probiotics (e.g., ice cream, cheeses, cereals, fruit juices, vegetables, and soy beans). Further, it seems that quorum sensing signal molecules released by probiotics may interact with human epithelial cells from intestine thus modulating several physiological functions. Under optimal processing conditions, functional microorganisms contribute to food functionality through their enzyme portfolio and the release of metabolites. Overproduction of free amino acids and vitamins are two classical examples. Besides, bioactive compounds (e.g., peptides, γ-amino butyric acid, and conjugated linoleic acid) may be released during food processing above the physiological threshold and they may exert various in vivo health benefits. Functional microorganisms are even more used in novel strategies for decreasing phenomenon of food intolerance (e.g., gluten intolerance) and allergy. By a critical approach, this review will aim at showing the potential of functional microorganisms for the quality of functional foods.

  17. Application of thermotolerant microorganisms for biofertilizer preparation.

    Science.gov (United States)

    Chen, Kuo-Shu; Lin, Yann-Shying; Yang, Shang-Shyng

    2007-12-01

    Intensive agriculture is practised in Taiwan, and compost application is very popular as a means of improving the soil physical properties and supplying plant nutrition. We tested the potential of inoculation with thermotolerant microorganisms to shorten the maturity and improve the quality of biofertilizer prepared by composting. Thermotolerant microorganisms were isolated from compost and reinoculated for the preparation of biofertilizer. The physical, chemical and biological properties of the biofertilizer were determined during composting. The effects of biofertilizer application on the growth and yield of rape were also studied. Among 3823 colonies of thermotolerant microorganisms, Streptomyces thermonitrificans NTU-88, Streptococcus sp. NTU-130 and Aspergillus fumigatus NTU-132 exhibited high growth rates and cellulolytic and proteolytic activities. When a mixture of rice straw and swine manure were inoculated with these isolates and composted for 61 days, substrate temperature increased initially and then decreased gradually during composting. Substrate pH increased from 7.3 to 8.5. Microbial inoculation enhanced the rate of maturity, and increased the content of ash and total and immobilized nitrogen, improved the germination rate of alfalfa seed, and decreased the content of total organic carbon and the carbon/nitrogen ratio. Biofertilizer application increased the growth and yield of rape. Inoculation of thermotolerant and thermophilic microorganisms to agricultural waste for biofertilizer preparation enhances the rate of maturity and improves the quality of the resulting biofertilizer. Inoculation of appropriate microorganisms in biofertilizer preparation might be usefully applied to agricultural situations.

  18. Oceans Past

    DEFF Research Database (Denmark)

    Based on research for the History of Marine Animal Populations project, Oceans Past examines the complex relationship our forebears had with the sea and the animals that inhabit it. It presents eleven studies ranging from fisheries and invasive species to offshore technology and the study of marine...... environmental history, bringing together the perspectives of historians and marine scientists to enhance understanding of ocean management of the past, present and future. In doing so, it also highlights the influence that changes in marine ecosystems have upon the politics, welfare and culture of human...

  19. Ocean energy

    International Nuclear Information System (INIS)

    2009-01-01

    There are 5 different ways of harnessing ocean energy: tides, swells, currents, osmotic pressure and deep water thermal gradients. The tidal power sector is the most mature. A single French site - The Rance tidal power station (240 MW) which was commissioned in 1966 produces 90% of the world's ocean energy. Smaller scale power stations operate around the world, 10 are operating in the European Union and 5 are being tested. Underwater generators and wave energy converters are expanding. In France a 1 km 2 sea test platform is planned for 2010. (A.C.)

  20. Microorganism identification technique using radioactive and fluorescent agent

    International Nuclear Information System (INIS)

    Silman, R.E.

    1983-01-01

    A method for identifying microorganisms is claimed. An emissive agent is added to a specimen of microorganisms to produce a mix of emissive products. These products are detected and characteristic pattern functioning as an identifier for the microorganisms is derived. The identifier is then compared with identifiers representing known microorganisms

  1. Food fermentations: Microorganisms with technological beneficial use

    DEFF Research Database (Denmark)

    Bourdichon, François; Casaregola, Serge; Farrokh, Choreh

    2012-01-01

    Microbial food cultures have directly or indirectly come under various regulatory frameworks in the course of the last decades. Several of those regulatory frameworks put emphasis on “the history of use”, “traditional food”, or “general recognition of safety”. Authoritative lists of microorganism......, legumes, cereals, beverages, and vinegar). We have also reviewed and updated the taxonomy of the microorganisms used in food fermentations in order to bring the taxonomy in agreement with the current standing in nomenclature....... cultures in practical use. However, as the focus mainly was on commercially available dairy cultures, there was an unmet need for a list with a wider scope. We present an updated inventory of microorganisms used in food fermentations covering a wide range of food matrices (dairy, meat, fish, vegetables...

  2. Biosurfactants, bioemulsifiers and exopolysaccharides from marine microorganisms.

    Science.gov (United States)

    Satpute, Surekha K; Banat, Ibrahim M; Dhakephalkar, Prashant K; Banpurkar, Arun G; Chopade, Balu A

    2010-01-01

    Marine biosphere offers wealthy flora and fauna, which represents a vast natural resource of imperative functional commercial grade products. Among the various bioactive compounds, biosurfactant (BS)/bioemulsifiers (BE) are attracting major interest and attention due to their structural and functional diversity. The versatile properties of surface active molecules find numerous applications in various industries. Marine microorganisms such as Acinetobacter, Arthrobacter, Pseudomonas, Halomonas, Myroides, Corynebacteria, Bacillus, Alteromonas sp. have been studied for production of BS/BE and exopolysaccharides (EPS). Due to the enormity of marine biosphere, most of the marine microbial world remains unexplored. The discovery of potent BS/BE producing marine microorganism would enhance the use of environmental biodegradable surface active molecule and hopefully reduce total dependence or number of new application oriented towards the chemical synthetic surfactant industry. Our present review gives comprehensive information on BS/BE which has been reported to be produced by marine microorganisms and their possible potential future applications.

  3. Physiologically anaerobic microorganisms of the deep subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, S.E. Jr.; Chung, K.T.

    1991-06-01

    This study seeks to determine numbers, diversity, and morphology of anaerobic microorganisms in 15 samples of subsurface material from the Idaho National Engineering Laboratory, in 18 samples from the Hanford Reservation and in 1 rock sample from the Nevada Test Site; set up long term experiments on the chemical activities of anaerobic microorganisms based on these same samples; work to improve methods for the micro-scale determination of in situ anaerobic microbial activity;and to begin to isolate anaerobes from these samples into axenic culture with identification of the axenic isolates.

  4. Risk Assessment of Genetically Modified Microorganisms

    DEFF Research Database (Denmark)

    Jacobsen, B. L.; Wilcks, Andrea

    2001-01-01

    the industry, national administration and research institutions were gathered to discuss which elements should be considered in a risk assessment of genetically modified microorganisms used as food or food ingredients. The existing EU and national regulations were presented, together with the experiences......The rapid development of recombinant DNA techniques for food organisms urges for an ongoing discussion on the risk assessment of both new as traditional use of microorganisms in food production. This report, supported by the Nordic Council of Ministers, is the result of a workshop where people from...... with risk assessment of these organisms in each Nordic country....

  5. Functional Properties of Microorganisms in Fermented Foods

    Directory of Open Access Journals (Sweden)

    Jyoti Prakash Tamang

    2016-04-01

    Full Text Available Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers.

  6. Ocean Acidification

    Science.gov (United States)

    Ludwig, Claudia; Orellana, Mónica V.; DeVault, Megan; Simon, Zac; Baliga, Nitin

    2015-01-01

    The curriculum module described in this article addresses the global issue of ocean acidification (OA) (Feely 2009; Figure 1). OA is a harmful consequence of excess carbon dioxide (CO[subscript 2]) in the atmosphere and poses a threat to marine life, both algae and animal. This module seeks to teach and help students master the cross-disciplinary…

  7. Ocean energies

    International Nuclear Information System (INIS)

    Charlier, R.H.; Justus, J.R.

    1993-01-01

    This timely volume provides a comprehensive review of current technology for all ocean energies. It opens with an analysis of ocean thermal energy conversion (OTEC), with and without the use of an intermediate fluid. The historical and economic background is reviewed, and the geographical areas in which this energy could be utilized are pinpointed. The production of hydrogen as a side product, and environmental consequences of OTEC plants are considered. The competitiveness of OTEC with conventional sources of energy is analysed. Optimisation, current research and development potential are also examined. Separate chapters provide a detailed examination of other ocean energy sources. The possible harnessing of solar ponds, ocean currents, and power derived from salinity differences is considered. There is a fascinating study of marine winds, and the question of using the ocean tides as a source of energy is examined, focussing on a number of tidal power plant projects, including data gathered from China, Australia, Great Britain, Korea and the USSR. Wave energy extraction has excited recent interest and activity, with a number of experimental pilot plants being built in northern Europe. This topic is discussed at length in view of its greater chance of implementation. Finally, geothermal and biomass energy are considered, and an assessment of their future is given. The authors also distinguished between energy schemes which might be valuable in less-industrialized regions of the world, but uneconomical in the developed countries. A large number of illustrations support the text. This book will be of particular interest to energy economists, engineers, geologists and oceanographers, and to environmentalists and environmental engineers

  8. Pesticides in Soil: Effects on Microorganisms

    Directory of Open Access Journals (Sweden)

    Ljiljana Radivojević

    2007-01-01

    Full Text Available Since their discovery to the present day, pesticides have been an inevitable segment of agricultural production and efforts have been made to synthesize compounds that would share a required efficacy along with selectivity, sufficient persistence on the object of protection and favourable toxicological and ecotoxicological characteristics so as to minimize their effect on the environment.When a pesticide gets into soil after application, it takes part in a number of physical, chemical and biological processes that depend not only on the compound itself, but a number of other factors as well, such as: physical, chemical and biological characteristics of soil; climatic factors, equipment used, method of application, method of storage, handling and disposal of waste, site characteristics (proximity of ground and underground waters, biodiversity and sensitivity of the environment. Microorganisms play an important role in pesticide degradation as they are able to utilize the biogenic elements from those compounds, as well as energy for their physiological processes. On the other hand, pesticides are more or less toxic substances that can have adverse effect on populations of microorganisms and prevent their development, reduce their abundance, deplete their taxonomic complexity and create communities with a lower level of diversity and reduced physiological activity.The article discusses complex interactions between pesticides and microorganisms in soil immediately after application and over the ensuing period. Data on changes in the abundance of some systematic and physiological groups of microorganisms, their microbial biomass and enzymatic activity caused under pesticide activity are discussed as indicators of these processes.

  9. [DIFFERENTIAL SENSITIVITY OF MICROORGANISMS TO POLYHEXAMETHYLENEGUANIDINE].

    Science.gov (United States)

    Lysytsya, A V; Mandygra, Y M; Bojko, O P; Romanishyna, O O; Mandygra, M S

    2015-01-01

    Factors identified that affect the sensitivity of microorganisms to polyhexamethyleneguanidine (PHMG). Salts of PHMG chloride, valerate, maleate, succinate was to use. Test strains of Esherichia coli, Staphylococcus aureus, Bacillus cereus, Leptospira interrogans, Paenibacillus larvae, Mycobacterium bovis, M. avium, M. fortuitum, Aspergillus niger and some strains of viruses are taken as objects of research. We have determined that the cytoplasm membrane phospholipids is main "target" for the polycation molecules of PHMG. A differential sensitivity of the microorganisms to this drug is primarily determined by relative amount of lipids in membrane and their accessibility. Such trends exist: increase the relative contents of anionic lipids and more negative surface electric potential of membrane, and reduction of the sizes fat acid remainder of lipids bring to increase of microorganism sensitivity. Types of anion salt PHMG just have a certain value. Biocide activity of PHMG chloride is more, than its salts with organic acid. Feasibility of combining PHMG with other biocides in the multicomponent disinfectants studied and analyzed. This combination does not lead to a significant increase in the sensitivity of microorganisms tested in most cases. Most species of pathogenic bacteria can be quickly neutralized by aqueous solutions of PHMG in less than 1% concentrations.

  10. Antibiotic Sensitivity Pattern of Microorganisms Isolated from ...

    African Journals Online (AJOL)

    Antibiotic sensitivity pattern of microorganisms isolated from smoked and frozen fishes sold in Benin and Warri metropolis were investigated. Adopting microbiological standard techniques, the results of the bacterial counts and fungal counts ranged from 5.4 x 106 (Ekpan market) to 25.1 x 106 (Ekpan market) and 1.1 x 105 ...

  11. Modelling the morphology of filamentous microorganisms

    DEFF Research Database (Denmark)

    Nielsen, Jens Bredal

    1996-01-01

    The rapid development in image analysis techniques has made it possible to study the growth kinetics of filamentous microorganisms in more detail than previously, However, owing to the many different processes that influence the morphology it is important to apply mathematical models to extract...

  12. Mechanisms of nickel toxicity in microorganisms

    Science.gov (United States)

    Macomber, Lee

    2014-01-01

    Summary Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological concern. To date, the mechanisms of nickel toxicity in microorganisms and higher eukaryotes are poorly understood. In this review, we summarize nickel homeostasis processes used by microorganisms and highlight in vivo and in vitro effects of exposure to elevated concentrations of nickel. On the basis of this evidence we propose four mechanisms of nickel toxicity: 1) nickel replaces the essential metal of metalloproteins, 2) nickel binds to catalytic residues of non-metalloenzymes; 3) nickel binds outside the catalytic site of an enzyme to inhibit allosterically, and 4) nickel indirectly causes oxidative stress. PMID:21799955

  13. False identification of other microorganisms as Staphylococcus ...

    African Journals Online (AJOL)

    Methods: 507 microorganisms which have been previously identified as S. aureus in 8 States in Southern Nigeria through characteristic morphology on blood agar, Gram staining, growth and fermentation on Mannitol Salt Agar and coagulase formation were collected. All the isolates were identified in this study through ...

  14. Host Defense against Opportunist Microorganisms Following Trauma.

    Science.gov (United States)

    1979-06-01

    Guide for Laboratory Animal, Resources, National Academy of Sciences - National Research Council. I ii t ___ ii A- KNOWLEDMENT The investigators express...and Candida albicans are the microorganisms which are most frequently associated with septic complica- tions in thermally injured patients. Management

  15. Atmospheric Sampling of Microorganisms with UAS

    Science.gov (United States)

    Schmale, D. G., III

    2017-12-01

    Many microorganisms relevant to crops, domestic animals, and humans are transported over long distances through the atmosphere. Some of these atmospheric microbes catalyze the freezing of water at higher temperatures and facilitate the onset of precipitation. A few have crossed continents. New technologies are needed to study the movement of microorganisms in the atmosphere. We have used unmanned aircraft systems (UAS) to study the transport of microorganisms tens to hundreds of meters above the ground. These UAS are equipped with unique devices for collecting microbes in the atmosphere during flight. Autonomous systems enable teams of UAS to perform complex atmospheric sampling tasks, and coordinate flight missions with one another. Data collected with UAS can be used to validate and improve disease forecasting models along highways in the sky, connecting transport scales across farms, states, and continents. Though terrestrial environments are often considered a major contributor to atmospheric microbial aerosols, little is known about aquatic sources of microbial aerosols. Droplets containing microorganisms can aerosolize from the water surface, liberating them into the atmosphere. We are using teams of unmanned surface vehicles (USVs) and UAS to study the aerosolization of microbes from aquatic environments. Controlled flume studies using highspeed video have allowed us to observe unique aerosolization phenomena that can launch microbes out of the water and into the air. Unmanned systems may be used to excite the next generation of biologists and engineers, and raise important ethical considerations about the future of human-robot interactions.

  16. Ecophysiology of microorganisms in microbial elctrolysis cells

    NARCIS (Netherlands)

    Croese, E.

    2012-01-01

    One of the main challenges for improvement of the microbial electrolysis cell (MEC) has been the reduction of the cost of the cathode catalyst. As catalyst at the cathode, microorganisms offer great possibilities. Previous research has shown the principle possibilities for the biocathode for H2

  17. Ecology and metagenomics of soil microorganisms

    Czech Academy of Sciences Publication Activity Database

    Baldrian, Petr; Head, I. M.; Prosser, J. I.; Schloter, M.; Smalla, K.; Tebbe, C. C.

    2011-01-01

    Roč. 78, č. 1 (2011), s. 1-2 ISSN 0168-6496 R&D Projects: GA MŠk LC06066; GA MŠk(CZ) LA10001 Institutional research plan: CEZ:AV0Z50200510 Keywords : microorganism * bioremediation * biogenesis of soil Subject RIV: EE - Microbiology, Virology Impact factor: 3.408, year: 2011

  18. Novel genome alteration system for microorganisms

    NARCIS (Netherlands)

    Daran, J.G.; Geertman, J.M.; Bolat, I.

    2015-01-01

    The invention relates to a set of targeting constructs, comprising a first construct comprising a recognition site for an endonuclease, a first region of homology with a target gene of a microorganism, and a first part of a selection marker, and a second construct comprising a second part of the

  19. The influence of selected nanomaterials on microorganisms

    Czech Academy of Sciences Publication Activity Database

    Brandeburová, P.; Birošová, L.; Vojs, M.; Kromka, Alexander; Gál, M.; Tichý, J.; Híveš, J.; Mackul´ak, T.

    2017-01-01

    Roč. 148, č. 3 (2017), s. 525-530 ISSN 0026-9247 R&D Projects: GA ČR GA15-01687S Institutional support: RVO:68378271 Keywords : nanomaterials * nanotechnologies * microorganisms * toxicity Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.282, year: 2016

  20. Artifical Microorganism Infection in Aviation Kerosene

    Directory of Open Access Journals (Sweden)

    Dušan Vallo

    2004-12-01

    Full Text Available The fuel used in the aviation engineering has to be clean and dry, it may not contain mechanical impurities and water. Water inaviation kerosene may occur in soluble and insoluble form. The danger inheres in the insoluble form, which may drop out in the crystallineform and cause various failures, such as those caused by mechanical impurities. The water assists in the biological matter formation createdby various species of microorganisms (bacteria, mould fungi and yeast. The microorganisms, present in water phase occurring on thebottom of tanks or on the interface water phase – kerosene, grow and reproduce and subsequently may pollute (impair the fuel by thebiomass or by the products of their metabolism. There is a possibility to infect the fuel artificially by a selected reference microorganismstrain, which usually occur in contaminated fuel, or by microorganisms which cause a biological contamination of aviation kerosene.Out of the selected reference strains used in the experiments, the reference strains of Proteus vulgaris, Sacharamyces cerevisiae andClostridium perfringens were not cultivated in the sterile aviation kerosene and the propagating nutrient medium. The aviation kerosene actsas a biocide medium for the presented reference microorganism strains.

  1. Novel Industrial Enzymes from Uncultured Arctic Microorganisms

    DEFF Research Database (Denmark)

    Vester, Jan Kjølhede

    , and reduce the risk of contaminations. Cold- and alkaline-active enzymes can be found in microorganisms adapted to living in natural environments with these conditions, which are extremely rare but found in the unique ikaite columns from SW Greenland (4-6 °C, pH >10). It is estimated that less than 1...

  2. [Sorption of microorganisms by fiber materials].

    Science.gov (United States)

    Nikovskaia, G N; Gordienko, A S; Globa, L I

    1986-01-01

    Candida guilliermondii and Escherichia coli cells were adsorbed on glass and basalt fibres with a similar specific surface, but with a different charge. The quantity of adsorbed microorganisms did not depend on the type and charge of a fibre surface. However, cells were adsorbed faster and more firmly on positively charged and uncharged fibres than on negatively charged fibres.

  3. Doppler speedometer for micro-organisms

    International Nuclear Information System (INIS)

    Penkov, F.; Tuleushev, A.; Lisitsyn, V.; Kim, S.; Tuleushev, Yu.

    1996-01-01

    Objective of Investigations: Development and creation of the Doppler speedometer for micro-organisms which allows to evaluate, in a real temporal scale, variations in the state of water suspension of micro-organisms under the effect of chemical, physical and other external actions. Statement of the Problem The main problem is absence of reliable, accessible for users and simple, in view of application, Doppler speedometers for micro-organisms. Nevertheless, correlation Doppler spectrometry in the regime of heterodyning the supporting and cell-scattered laser radiation is welt known. The main idea is that the correlation function of photo-current pulses bears an information on the averages over the assembly of cell velocities. For solving the biological problems, construction of auto-correlation function in the real-time regime with the delay time values comprising, function in the real-time regime with the delay time values comprising, nearly, 100 me (10 khz) or higher is needed. Computers of high class manage this problem using but the program software. Due to this, one can simplify applications of the proposed techniques provided he creates the Doppler speedometer for micro-organism on a base of the P entium . Expected Result Manufactured operable mock-up of the Doppler speedometer for micro-organisms in a form of the auxiliary computer block which allows to receive an information, in the real time scale, on the results of external effects of various nature on the cell assembly in transparent medium with a small volume of the studied cell suspension

  4. Proceedings of oceans '91

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This volume contains the proceedings of the Oceans '91 Conference. Topics addressed include: ocean energy conversion, marine communications and navigation, ocean wave energy conversion, environmental modeling, global climate change, ocean minerals technology, oil spill technology, and submersible vehicles

  5. Ocean acidification

    International Nuclear Information System (INIS)

    Soubelet, Helene; Veyre, Philippe; Monnoyer-Smith, Laurence

    2017-09-01

    This brief publication first recalls and outlines that ocean acidification is expected to increase, and will result in severe ecological impacts (more fragile coral reefs, migration of species, and so on), and therefore social and economic impacts. This issue is particularly important for France who possesses the second exclusive maritime area in the world. The various impacts of ocean acidification on living species is described, notably for phytoplankton, coral reefs, algae, molluscs, and fishes. Social and economic impacts are also briefly presented: tourism, protection against risks (notably by coral reefs), shellfish aquaculture and fishing. Issues to be addressed by scientific research are evoked: interaction between elements of an ecosystem and between different ecosystems, multi-stress effects all along organism lifetime, vulnerability and adaptability of human societies

  6. A Holographic Microscope for Detection of Microorganisms on Icy Worlds

    Science.gov (United States)

    Lindensmith, C. A.; Nadeau, J. L.; Deming, J. W.; Showalter, G. M.; Rider, S.; Bedrossian, M.

    2015-12-01

    Holography is a well-established imaging technique that uses the interference of light to record and reproduce three-dimensional images of objects. Its use began in the 1960s with the invention of the laser. Digital holographic microscopy (DHM) has several advantages over ordinary imaging microscopy which make it ideal for field and astrobiology use, including no need for focus or scanning so that instruments are readily made autonomous. DHM can produce simultaneous bright-field and quantitative phase-contrast images of the same field, providing additional information about transparent objects, e.g., refractive index and/or thickness; thus it inherently supports effective label-free imaging. We have built a fieldable DHM for detection of microorganisms in bodies of water and in brines collected from sea ice. Ice that appears solid to the eye contains interconnected brine-filled microscopic pores and veins which are occupied by populations of prokaryotes and eukaryotes. The presence of life in "solid" ice has important implications for exploration of icy worlds, where it is unlikely that the first missions will be able to access the subsurface oceans. Using this new instrument, we examined several dozen samples from three different sites around Nuuk, Greenland. In all samples, mixed populations of both prokaryotic and eukaryotic microorganisms were observed. Many of the organisms were motile immediately upon extraction from sea ice, and others became motile after warming or addition of sugars and/or amino acids. Meaningful motility was readily distinguished from turbulence or fluid flow. The spatial resolution of the instrument was better than 1 μm, leading to unambiguous recognition of subcellular structures in eukaryotes, including nuclei and chloroplasts. We present mission scenrios for both orbiters and landers in which DHM may be used as a valuable complement to chemical-based life detection techniques for discovery of cellular life on icy worlds.

  7. Combined effect of CO2 and light on the N2-fixing cyanobacterium Trichodesmium IMS101: Physiological responses 1[OA

    Czech Academy of Sciences Publication Activity Database

    Kranz, S. A.; Levitan, O.; Richter, K.-U.; Prášil, Ondřej; Berman-Frank, I.; Rost, B.

    2010-01-01

    Roč. 154, č. 1 (2010), s. 334-345 ISSN 0032-0889 R&D Projects: GA ČR GA206/08/1683 Institutional research plan: CEZ:AV0Z50200510 Keywords : Trichodesmium IMS101 * cyanobacterium * CO2 Subject RIV: EE - Microbiology, Virology Impact factor: 6.451, year: 2010

  8. Structure, biosynthesis and function of unusual lipids A from nodule-inducing and N2-fixing bacteria.

    Science.gov (United States)

    Choma, Adam; Komaniecka, Iwona; Zebracki, Kamil

    2017-02-01

    This review focuses on the chemistry and structures of (Brady)rhizobium lipids A, indispensable parts of lipopolysaccharides. These lipids contain unusual (ω-1) hydroxylated very long chain fatty acids, which are synthesized by a very limited group of bacteria, besides rhizobia. The significance and requirement of the very long chain fatty acids for outer membrane stability as well as the genetics of the synthesis pathway are discussed. The biological role of these fatty acids for bacterial life in extremely different environments (soil and intracellular space within nodules) is also considered. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Identification of Microorganisms by Modern Analytical Techniques.

    Science.gov (United States)

    Buszewski, Bogusław; Rogowska, Agnieszka; Pomastowski, Paweł; Złoch, Michał; Railean-Plugaru, Viorica

    2017-11-01

    Rapid detection and identification of microorganisms is a challenging and important aspect in a wide range of fields, from medical to industrial, affecting human lives. Unfortunately, classical methods of microorganism identification are based on time-consuming and labor-intensive approaches. Screening techniques require the rapid and cheap grouping of bacterial isolates; however, modern bioanalytics demand comprehensive bacterial studies at a molecular level. Modern approaches for the rapid identification of bacteria use molecular techniques, such as 16S ribosomal RNA gene sequencing based on polymerase chain reaction or electromigration, especially capillary zone electrophoresis and capillary isoelectric focusing. However, there are still several challenges with the analysis of microbial complexes using electromigration technology, such as uncontrolled aggregation and/or adhesion to the capillary surface. Thus, an approach using capillary electrophoresis of microbial aggregates with UV and matrix-assisted laser desorption ionization time-of-flight MS detection is presented.

  10. Assessment of microorganisms from Indonesian Oil Fields

    Energy Technology Data Exchange (ETDEWEB)

    Kadarwati, S.; Udiharto, M.; Rahman, M.; Jasjfi, E.; Legowo, E.H. [Research and Development Centre for Oil and Gas Technology LEMIGAS, Jakarta Selatan (Indonesia)

    1995-12-31

    Petroleum resources have been the mainstay of the national development in Indonesia. However, resources are being depleted after over a century of exploitation, while the demand continues to grow with the rapid economic development of the country. In facing the problem, EOR has been applied in Indonesia, such as the steamflooding project in Duri field, but a more energy efficient technology would be preferable. Therefore, MEOR has been recommended as a promising solution. Our study, aimed at finding indigenous microorganisms which can be developed for application in MEOR, has isolated microbes from some oil fields of Indonesia. These microorganisms have been identified, their activities studied, and the effects of their metabolisms examined. This paper describes the research carried out by LEMIGAS in this respect, giving details on the methods of sampling, incubation, identification, and activation of the microbes as well as tests on the effects of their metabolites, with particular attention to those with potential for application in MEOR.

  11. UV inactivation of pathogenic and indicator microorganisms

    International Nuclear Information System (INIS)

    Chang, J.C.; Ossoff, S.F.; Lobe, D.C.; Dorfman, M.H.; Dumais, C.M.; Qualls, R.G.; Johnson, J.D.

    1985-01-01

    Survival was measured as a function of the dose of germicidal UV light for the bacteria Escherichia coli, Salmonella typhi, Shigella sonnei, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis spores, the enteric viruses poliovirus type 1 and simian rotavirus SA11, the cysts of the protozoan Acanthamoeba castellanii, as well as for total coliforms and standard plate count microorganisms from secondary effluent. The doses of UV light necessary for a 99.9% inactivation of the cultured vegetative bacteria, total coliforms, and standard plate count microorganisms were comparable. However, the viruses, the bacterial spores, and the amoebic cysts required about 3 to 4 times, 9 times, and 15 times, respectively, the dose required for E. coli. These ratios covered a narrower relative dose range than that previously reported for chlorine disinfection of E. coli, viruses, spores, and cysts

  12. UV inactivation of pathogenic and indicator microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J.C.; Ossoff, S.F.; Lobe, D.C.; Dorfman, M.H.; Dumais, C.M.; Qualls, R.G.; Johnson, J.D.

    1985-06-01

    Survival was measured as a function of the dose of germicidal UV light for the bacteria Escherichia coli, Salmonella typhi, Shigella sonnei, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis spores, the enteric viruses poliovirus type 1 and simian rotavirus SA11, the cysts of the protozoan Acanthamoeba castellanii, as well as for total coliforms and standard plate count microorganisms from secondary effluent. The doses of UV light necessary for a 99.9% inactivation of the cultured vegetative bacteria, total coliforms, and standard plate count microorganisms were comparable. However, the viruses, the bacterial spores, and the amoebic cysts required about 3 to 4 times, 9 times, and 15 times, respectively, the dose required for E. coli. These ratios covered a narrower relative dose range than that previously reported for chlorine disinfection of E. coli, viruses, spores, and cysts.

  13. Influence of near ultraviolet light on microorganisms

    International Nuclear Information System (INIS)

    Fraikin, G.Y.A.; Rubin, L.B.

    1980-01-01

    Our results and the recent literature data on the biological action of near ultraviolet light (300-380 nm) are examined in the review. Factual material is presented on the principles governing the manifestation of the following effects of near ultraviolet light in microorganisms: inactivation, delayed growth, photoreactivation, photoprotection, photoinduced sporulation (in fungi), and carotene synthesis. The mature and possible mechanisms of the effects examined are discussed

  14. Chemosensing in microorganisms to practical biosensors

    OpenAIRE

    Ghosh, Surya K.; Kundu, Tapanendu; Sain, Anirban

    2012-01-01

    Microorganisms like bacteria can sense concentration of chemo-attractants in its medium very accurately. They achieve this through interaction between the receptors on their cell surface and the chemo-attractant molecules (like sugar). But the physical processes like diffusion set some limits on the accuracy of detection which was discussed by Berg and Purcell in the late seventies. We have a re-look at their work in order to assess what insight it may offer towards making efficient, practica...

  15. Bioemulsan Production by Iranian Oil Reservoirs Microorganisms

    Directory of Open Access Journals (Sweden)

    A Amiriyan, M Mazaheri Assadi, VA Saggadian, A Noohi

    2004-10-01

    Full Text Available The biosurfactants are believed to be surface active components that are shed into the surrounding medium during the growth of the microorganisms. The oil degrading microorganism Acinetobacter calcoaceticus RAG-1 produces a poly-anionic biosurfactant, hetero-polysaccharide bioemulsifier termed as emulsan which forms and stabilizes oil-water emulsions with a variety of hydrophobic substrates. In the present paper results of the possibility of biosurfactant (Emulsan production by microorganisms isolated from Iranian oil reservoirs is presented. Fourthy three gram negative and gram positive, non fermentative, rod bacilli and coccobacilli shaped baceria were isolated from the oil wells of Bibi Hakimeh, Siri, Maroon, Ilam , East Paydar and West Paydar. Out of the isolated strains, 39 bacterial strains showed beta haemolytic activity, further screening revealed the emulsifying activity and surface tension. 11 out of 43 tested emulsifiers were identified as possible biosurfactant producers and two isolates produced large surface tension reduction, indicating the high probability of biosurfactant production. Further investigation revealed that, two gram negative, oxidase negative, aerobic and coccoid rods isolates were the best producers and hence designated as IL-1, PAY-4. Whole culture broth of isolates reduced surface tension from 68 mN /m to 30 and 29.1mN/m, respectively, and were stable during exposure to high salinity (10%NaCl and elevated temperatures(120C for 15 min .

  16. [Succession of chitinolytic microorganisms in chernozem soil].

    Science.gov (United States)

    Manucharova, N A; Belova, E V; Vorob'ev, A V; Polianskaia, L M; Stepanov, A L

    2005-01-01

    The chitinolytic prokaryotic and eukaryotic microbial complex of chernozem soil has been investigated in the course of a succession initiated by the introduction of chitin and humidification. The dynamics of the cell numbers of chitinolytic microorganisms and of their biomass was assessed by fluorescent microscopy and by inoculation of selective media. Emission of carbon dioxide and nitrous oxide, as well as dinitrogen fixation, was assessed by gas chromatography. It was found that, when the succession was initiated by the introduction of both chitin and humidification, it resulted in greater cell numbers and biomass of chitinolytic microorganisms and higher levels of CO2 and N2O emission and of nitrogen fixation than when the succession was initiated by humidification alone. As compared to the control samples, a significant (twofold) increase in the prokaryote cell number and biomass was found on the fourth day of the succession initiated by humidification and introduction of chitin. One week after the initiation of succession, the fungal biomass and length of mycelium were twice as high as those in the control samples. These results led to the conclusion that chitin utilization in chernozem soil starts during the initial stages of succession and is performed by both prokaryotic and eukaryotic microorganisms.

  17. Monitoring of psychrotrophic microorganisms in raw milk

    Directory of Open Access Journals (Sweden)

    Radka Burdychová

    2008-01-01

    Full Text Available The group of psychrotrophic microorganisms belongs to the microorganisms representing a risk for human health as well as a risk of milk and milk products spoilage. Some genus are considered to be significant producers of proteolytic and lipolytic enzymes. In this work, we analysed raw milk samples (n = 109 originated from 26 different suppliers from the area of North and Middle Moravia. The screening was performed from March 2007 to February 2008. The total bacterial counts (TBC ranged between 3.2 × 103 to 8.3 × 106 CFU/ml. The psychrotrophic bacterial counts (PBC ranged between 1.0 × 103 to 8.2 × 106 CFU/ml. Total of 48.62 % and 48.62 % of samples exceeded the hygienic limit in raw milk for TBC and PBC, respectively. The correlation between TBC and PBC was highly significant (r = 0.87.Significantly higher (P < 0.05 numbers of psychrotrophic microorganisms were detected in summer months. The identification of isolates was carried out and all strains were sreened for ability to produce proteolytic and lipolytic enzymes. The most commonly identified genus in raw milk was of the genus Pseudomonas. The ability to produce proteases or lipases was found at 76 % identified bacterial strains.

  18. Selection of mesophilic microorganisms with biodesulfuration capacity

    International Nuclear Information System (INIS)

    Madero, A; Mogollon, L. I; Mora, A.L; Osorio, L.F

    1998-01-01

    The development of bio desulfurization (BDS) processes for hydrocarbons requires fast and reliable methods for the screening of microorganisms. This work shows the results of the screening process for indigenous Colombian strains with a BDS potential capacity. The main criteria for the screening were the qualitative and quantitative determination of 2-hydroxybiphenyl (2-HBP) as the typical metabolite of the 4S specific pathway. Microorganisms were cultured by two methodologies, A and B, using DBT as the model compound. The quantitative determination of metabolites was made by HPLC. Thirteen strains were evaluated, including the strain Rhodococcus rhodocrous IGTS8, by methods A and B. In method A, the inoculum was exposed to DBT since the beginning of the culture. Method B, employed two stages: (i) Growth period under limiting sulfur conditions, (ii) Transforming period, in which the pre-grown inoculum was exposed to the organic sulfur substrate. The culture of mesophilic microorganisms isolated by method B, served to find a mechanism for the organic sulfur metabolism, and the evaluation of the sulfur removal capability of five indigenous strains. In the cultures of these strains, 2- hydroxybiphenyl (2-HBP) was detected as a byproduct of DBT metabolism, both qualitatively and quantitatively

  19. Magnetotaxy in microorganisms of Rio de Janeiro region: an overview

    International Nuclear Information System (INIS)

    Barros, H.G. de P.L. de; Esquivel, D.M.S.

    1983-01-01

    Some characteristics of several magnetotactic microorganisms found in sediments collected in Rio de Janeiro region are presented. The study of magnetic characteristics of these microorganisms indicate some general properties of the magnetotaxy phenomenons. (L.C.) [pt

  20. Planet Ocean

    Science.gov (United States)

    Afonso, Isabel

    2014-05-01

    A more adequate name for Planet Earth could be Planet Ocean, seeing that ocean water covers more than seventy percent of the planet's surface and plays a fundamental role in the survival of almost all living species. Actually, oceans are aqueous solutions of extraordinary importance due to its direct implications in the current living conditions of our planet and its potential role on the continuity of life as well, as long as we know how to respect the limits of its immense but finite capacities. We may therefore state that natural aqueous solutions are excellent contexts for the approach and further understanding of many important chemical concepts, whether they be of chemical equilibrium, acid-base reactions, solubility and oxidation-reduction reactions. The topic of the 2014 edition of GIFT ('Our Changing Planet') will explore some of the recent complex changes of our environment, subjects that have been lately included in Chemistry teaching programs. This is particularly relevant on high school programs, with themes such as 'Earth Atmosphere: radiation, matter and structure', 'From Atmosphere to the Ocean: solutions on Earth and to Earth', 'Spring Waters and Public Water Supply: Water acidity and alkalinity'. These are the subjects that I want to develop on my school project with my pupils. Geographically, our school is located near the sea in a region where a stream flows into the sea. Besides that, our school water comes from a borehole which shows that the quality of the water we use is of significant importance. This project will establish and implement several procedures that, supported by physical and chemical analysis, will monitor the quality of water - not only the water used in our school, but also the surrounding waters (stream and beach water). The samples will be collected in the borehole of the school, in the stream near the school and in the beach of Carcavelos. Several physical-chemical characteristics related to the quality of the water will

  1. Microorganisms and methods for producing pyruvate, ethanol, and other compounds

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Jennifer L.; Zhang, Xiaolin

    2017-12-26

    Microorganisms comprising modifications for producing pyruvate, ethanol, and other compounds. The microorganisms comprise modifications that reduce or ablate activity of one or more of pyruvate dehydrogenase, 2-oxoglutarate dehydrogenase, phosphate acetyltransferase, acetate kinase, pyruvate oxidase, lactate dehydrogenase, cytochrome terminal oxidase, succinate dehydrogenase, 6-phosphogluconate dehydrogenase, glutamate dehydrogenase, pyruvate formate lyase, pyruvate formate lyase activating enzyme, and isocitrate lyase. The microorganisms optionally comprise modifications that enhance expression or activity of pyruvate decarboxylase and alcohol dehydrogenase. The microorganisms are optionally evolved in defined media to enhance specific production of one or more compounds. Methods of producing compounds with the microorganisms are provided.

  2. Extracellular electron transfer mechanisms between microorganisms and minerals

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Liang; Dong, Hailiang; Reguera, Gemma; Beyenal, Haluk; Lu, Anhuai; Liu, Juan; Yu, Han-Qing; Fredrickson, James K.

    2016-08-30

    Electrons can be transferred from microorganisms to multivalent metal ions that are associated with minerals and vice versa. As the microbial cell envelope is neither physically permeable to minerals nor electrically conductive, microorganisms have evolved strategies to exchange electrons with extracellular minerals. In this Review, we discuss the molecular mechanisms that underlie the ability of microorganisms to exchange electrons, such as c-type cytochromes and microbial nanowires, with extracellular minerals and with microorganisms of the same or different species. Microorganisms that have extracellular electron transfer capability can be used for biotechnological applications, including bioremediation, biomining and the production of biofuels and nanomaterials.

  3. Screening of biosurfactants from cloud microorganisms

    Science.gov (United States)

    Sancelme, Martine; Canet, Isabelle; Traikia, Mounir; Uhliarikova, Yveta; Capek, Peter; Matulova, Maria; Delort, Anne-Marie; Amato, Pierre

    2015-04-01

    The formation of cloud droplets from aerosol particles in the atmosphere is still not well understood and a main source of uncertainties in the climate budget today. One of the principal parameters in these processes is the surface tension of atmospheric particles, which can be strongly affected by trace compounds called surfactants. Within a project devoted to bring information on atmospheric surfactants and their effects on cloud droplet formation, we focused on surfactants produced by microorganisms present in atmospheric waters. From our unique collection of microorganisms, isolated from cloud water collected at the Puy-de-Dôme (France),1 we undertook a screening of this bank for biosurfactant producers. After extraction of the supernatants of the pure cultures, surface tension of crude extracts was determined by the hanging drop technique. Results showed that a wide variety of microorganisms are able to produce biosurfactants, some of them exhibiting strong surfactant properties as the resulting tension surface decreases to values less then 35 mN.m-1. Preliminary analytical characterization of biosurfactants, obtained after isolation from overproducing cultures of Rhodococcus sp. and Pseudomonas sp., allowed us to identify them as belonging to two main classes, namely glycolipids and glycopeptides. 1. Vaïtilingom, M.; Attard, E.; Gaiani, N.; Sancelme, M.; Deguillaume, L.; Flossmann, A. I.; Amato, P.; Delort, A. M. Long-term features of cloud microbiology at the puy de Dôme (France). Atmos. Environ. 2012, 56, 88-100. Acknowledgements: This work is supported by the French-USA ANR SONATA program and the French-Slovakia programs Stefanik and CNRS exchange.

  4. Impact of microorganism on polonium volatilization

    International Nuclear Information System (INIS)

    Momoshima, N.; Ishida, A.; Fukuda, A.; Yoshinaga, C.

    2007-01-01

    Volatilization of polonium by microorganisms, Chromobacterium violaceum, Escherichia coli and Bacillus subtilis was examined for pure cultures in LB medium at 30 deg C, showing relative Po emission intensity 100, 10 and 1, respectively. Chromobacterium violaceum pre-cultured in LB medium without Po and suspended in water with Po showed high Po volatilization in spite of poor nutriment condition. Antibiotics inhibit volatilization of Po and cultivation at low temperature greatly reduced volatilization. The results strongly support the biological effects on Po volatilization. (author)

  5. Microorganisms in human milk: lights and shadows.

    Science.gov (United States)

    Civardi, Elisa; Garofoli, Francesca; Tzialla, Chryssoula; Paolillo, Piermichele; Bollani, Lina; Stronati, Mauro

    2013-10-01

    Human milk has been traditionally considered germ free, however, recent studies have shown that it represents a continuous supply of commensal and potentially probiotic bacteria to the infant gut. Mammary microbioma may exercise anti-infective, anti-inflammatory, immunomodulatory and metabolic properties. Moreover human milk may be a source of pathogenic microorganism during maternal infection, if contaminated during expression or in case of vaccination of the mother. The non-sterility of breast milk can, thus, be seen as a protective factor, or rarely, as a risk factor for the newborn.

  6. Microbial biogeography: putting microorganisms on the map.

    Science.gov (United States)

    Martiny, Jennifer B Hughes; Bohannan, Brendan J M; Brown, James H; Colwell, Robert K; Fuhrman, Jed A; Green, Jessica L; Horner-Devine, M Claire; Kane, Matthew; Krumins, Jennifer Adams; Kuske, Cheryl R; Morin, Peter J; Naeem, Shahid; Ovreås, Lise; Reysenbach, Anna-Louise; Smith, Val H; Staley, James T

    2006-02-01

    We review the biogeography of microorganisms in light of the biogeography of macroorganisms. A large body of research supports the idea that free-living microbial taxa exhibit biogeographic patterns. Current evidence confirms that, as proposed by the Baas-Becking hypothesis, 'the environment selects' and is, in part, responsible for spatial variation in microbial diversity. However, recent studies also dispute the idea that 'everything is everywhere'. We also consider how the processes that generate and maintain biogeographic patterns in macroorganisms could operate in the microbial world.

  7. Microorganisms and biomolecules in space hard environment

    Science.gov (United States)

    Horneck, G.

    1981-01-01

    Microorganisms and biomolecules exposed to space vacuum and to different intensities of selected wavelengths of solar ultraviolet radiation is studied. The influence of these factors, applied singly or simultaneously, on the integrity of microbial systems and biomolecules is measured. Specifically, this experiment will study in Bacillus subtilis spores (1) disturbances in subsequent germination, outgrowth, and colony formation; (2) photochemical reactions of the DNA and protein in vivo and in vitro and their role in biological injury; and (3) the efficiency of repair processes in these events.

  8. Engineering photosynthesis in plants and synthetic microorganisms.

    Science.gov (United States)

    Maurino, Veronica G; Weber, Andreas P M

    2013-01-01

    Photosynthetic organisms, such as cyanobacteria, algae, and plants, sustain life on earth by converting light energy, water, and CO(2) into chemical energy. However, due to global change and a growing human population, arable land is becoming scarce and resources, including water and fertilizers, are becoming exhausted. It will therefore be crucial to design innovative strategies for sustainable plant production to maintain the food and energy bases of human civilization. Several different strategies for engineering improved photosynthesis in crop plants and introducing novel photosynthetic capacity into microorganisms have been reviewed.

  9. Microorganisms as Indicators of Soil Health

    DEFF Research Database (Denmark)

    Nielsen, M. N.; Winding, A.; Binnerup, S.

    ecosystem parameters representing policy relevant end points. It is further recommended to identify a specific minimum data set for specific policy relevant end points, to carefully establish baseline values, to improve scientific knowledge on biodiversity and modelling of soil data, and to implement new......Microorganisms are an essential part of living soil and of outmost importance for soil health. As such they can be used as indicators of soil health. This report reviews the current and potential future use of microbial indicators of soil health and recommends specific microbial indicators for soil...... indicators into soil monitoring programmes as they become applicable....

  10. Ocean Uses: Hawaii (PROUA)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Pacific Regional Ocean Uses Atlas (PROUA) Project is an innovative partnership between NOAA and the Bureau of Ocean Energy Management (BOEM) designed to...

  11. Microorganisms as bioindicators of pollutants in soil

    Directory of Open Access Journals (Sweden)

    Milošević Nada

    2010-01-01

    Full Text Available Microorganisms are the predominant portion of the soil's biological phase and they are indicators of soil health and quality. Soil microorganisms a take part in degradation of organic and inorganic compounds, b their activity, number and diversity may serve as bioindicators of toxic effects on soil biological activity, c some microbial species may be used for soil bioremediation and d some sensitive microbes are used in eco-toxicity tests. The primary microbial population starts to decompose herbicides several days after their arrival into the soil. The secondary population produces induced enzymes and decomposes herbicides after a period of adaptation. Certain microbial groups are indifferent to the applied herbicides. Effect of heavy metals on soil microbial activity depends on the element, their concentration, microbial species, as well as physical and chemical soil properties. Toxic level of individual pollutants depends on their origin and composition. However, combined application of chemicals makes room for the occurrence of synergistic toxic effects detrimental for the ecosystem and human health. .

  12. Identification of periodontopathogen microorganisms by PCR technique

    Directory of Open Access Journals (Sweden)

    Milićević Radovan

    2008-01-01

    Full Text Available INTRODUCTION Periodontitis is an inflammatory disease of the supporting tissues of teeth and is a major cause of tooth loss in adults. The onset and progression of periodontal disease is attributed to the presence of elevated levels of a consortium of pathogenic bacteria. Gram negative bacteria, mainly strict anaerobes, play the major role. OBJECTIVE The present study aimed to assess the presence of the main types of microorganisms involved in the aetiopathogenesis of periodontal disease: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Eikenella corrodens, Treponema denticola, Tanerella forsythia and Prevotella intermedia in different samples collected from the oral cavity of 90 patients diagnosed with periodontitis. METHOD Bacterial DNA detection was performed in diverse biological materials, namely in dental plaque, gingival tissue and saliva, by means of multiplex PCR, a technique that allows simultaneous identification of two different bacterial genomes. RESULTS In the dental plaque of the periodontitis patients, Treponema denticola dominated. In the gingival tissue, Tannerella forsythia and Treponema denticola were the microbiota most frequently detected, whilst in saliva Treponema denticola and Eikenella corrodens were found with the highest percentage. CONCLUSION The identification of microorganisms by multiplex PCR is specific and sensitive. Rapid and precise assessment of different types of periodontopathogens is extremely important for early detection of the infection and consequently for the prevention and treatment of periodontal disease. In everyday clinical practice, for routine bacterial evaluation in patients with periodontal disease, the dental plaque is the most suitable biological material, because it is the richest in periodontal bacteria.

  13. Sterilization of Microorganisms by Ozone and Ultrasound

    Science.gov (United States)

    Krasnyj, V. V.; Klosovskij, A. V.; Panasko, T. A.; Shvets, O. M.; Semenova, O. T.; Taran, V. S.; Tereshin, V. I.

    2008-03-01

    The results of recent experimental methods of sterilization of microorganisms with the use of ozone and ultrasound are presented. The main aim was to optimize the process of sterilization in water solution taking into account the ozone concentration, the power of ultrasonic emitter and the temperature of water. In the present work, the ultrasonic cavitation with simultaneous ozone generation has been used. The high ozone concentration in water solution was achieved by two-barrier glow discharge generated at atmospheric pressure and a cooling thermo-electric module. Such a sterilizer consists of ozone generator in a shape of flat electrodes covered with dielectric material and a high-voltage pulsed power supply of 250 W. The sterilization camera was equipped with ultrasonic source operated at 100 W. The experiments on the inactivation of bacteria of the Bacillus Cereus type were carried out in the distilled water saturated by ozone. The ozone concentration in the aqueous solution was 10 mg/1, whereas the ozone concentration at the output of ozone generator was 30 mg/1. The complete inactivation of spores took 15 min. Selection of the temperature of water, the ozone concentrations and ultrasonic power allowed to determine the time necessary for destroying the row of microorganisms.

  14. Venturing into new realms? Microorganisms in space.

    Science.gov (United States)

    Moissl-Eichinger, Christine; Cockell, Charles; Rettberg, Petra

    2016-09-01

    One of the biggest challenges of science is the determination of whether extraterrestrial life exists. Although potential habitable areas might be available for complex life, it is more likely that microbial life could exist in space. Many extremotolerant and extremophilic microbes have been found to be able to withstand numerous, combined environmental factors, such as high or low temperatures and pressures, high-salt conditions, high doses of radiation, desiccation or nutrient limitations. They may even survive the transit from one planet to another. Terrestrial Mars-analogue sites are one focus of researchers, in order to understand the microbial diversity in preparation for upcoming space missions aimed at the detection of life. However, such missions could also pose a risk with respect to contamination of the extraterrestrial environment by accidentally transferred terrestrial microorganisms. Closer to the Earth, the International Space Station is the most enclosed habitat, where humans work and live-and with them numerous microorganisms. It is still unknown how microbes adapt to this environment, possibly even creating a risk for the crew. Information on the microbiology of the ISS will have an impact on the planning and implementation of long-term human spaceflights in order to ensure a safe, stable and balanced microbiome on board. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Medical Significance of Microorganisms in Spacecraft Environment

    Science.gov (United States)

    Pierson, Duane L.; Ott, C. Mark

    2007-01-01

    Microorganisms can spoil food supplies, contaminate drinking water, release noxious volatile compounds, initiate allergic responses, contaminate the environment, and cause infectious diseases. International acceptability limits have been established for bacterial and fungal contaminants in air and on surfaces, and environmental monitoring is conducted to ensure compliance. Allowable levels of microorganism in water and food have also been established. Environmental monitoring of the space shuttle, the Mir, and the ISS have allowed for some general conclusions. Generally, the bacteria found in air and on interior surfaces are largely of human origin such as Staphylococcus spp., Micrococcus spp. Common environmental genera such as Bacillus spp. are the most commonly isolated bacteria from all spacecraft. Yeast species associated with humans such as Candida spp. are commonly found. Aspergillus spp., Penicillium spp., and Cladosporium spp. are the most commonly isolated filamentous fungi. Microbial levels in the environment differ significantly depending upon humidity levels, condensate accumulation, and availability of carbon sources. However, human "normal flora" of bacteria and fungi can result in serious, life-threatening diseases if human immunity is compromised. Disease incidence is expected to increase as mission duration increases.

  16. Bioremediation of trinitrotolulene by a ruminal microorganism

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Taejin; Williamson, K.J.; Craig, A.M. [Oregon State Univ., Corvallis, OR (United States)

    1995-10-01

    2,4,6-trinitrotoluene (TNT) has been widely used for the production of explosives because of its low boiling point, high stability, low impact sensitivity, and safe manufacture. More than 1,100 military facilities, each potentially contaminated with munitions waste, are expected to require treatment of more than one million cubic yards of contaminated soils. The cost associated with remediation of these sites has been estimated to be in excess of $1.5 billion. Recently, researchers have studied ruminal microorganisms in relation to their ability to degrade xenobiotic compounds. Many of these organisms are strict anaerobes with optimal redox potentials as low as -420 mV. Ruminal organisms have been shown capable of destroying some pesticides, such as parathion, p-nitrophenol, and biphenyl-type compounds; thiono isomers, and nitrogen-containing heterocyclic plant toxins such as the pyrrolizidine alkaloids. Many of these compounds have structures similar to TNT. A TNT-degrading ruminal microorganism has been isolated from goat rumen fluid with successive enrichments on triaminotoluene (TAT) and TNT. The isolate, designated G.8, utilizes nitrate and lactate as the primary energy source. G.8 was able to tolerate and metabolite levels of TNT up to the saturation point of 125 mg/l.

  17. Physiological ecology of microorganisms in Subglacial Lake Whillans

    Directory of Open Access Journals (Sweden)

    Trista J Vick-Majors

    2016-10-01

    Full Text Available Subglacial microbial habitats are widespread in glaciated regions of our planet. Some of these environments have been isolated from the atmosphere and from sunlight for many thousands of years. Consequently, ecosystem processes must rely on energy gained from the oxidation of inorganic substrates or detrital organic matter. Subglacial Lake Whillans (SLW is one of more than 400 subglacial lakes known to exist under the Antarctic ice sheet; however, little is known about microbial physiology and energetics in these systems. When it was sampled through its 800 m thick ice cover in 2013, the SLW water column was shallow (~2 m deep, oxygenated, and possessed sufficient concentrations of C, N, and P substrates to support microbial growth. Here, we use a combination of physiological assays and models to assess the energetics of microbial life in SLW. In general, SLW microorganisms grew slowly in this energy-limited environment. Heterotrophic cellular carbon turnover times, calculated from 3H-thymidine and 3H-leucine incorporation rates, were long (60 to 500 days while cellular doubling times averaged 196 days. Inferred growth rates (average ~0.006 d-1 obtained from the same incubations were at least an order of magnitude lower than those measured in Antarctic surface lakes and oligotrophic areas of the ocean. Low growth efficiency (8% indicated that heterotrophic populations in SLW partition a majority of their carbon demand to cellular maintenance rather than growth. Chemoautotrophic CO2-fixation exceeded heterotrophic organic C-demand by a factor of ~1.5. Aerobic respiratory activity associated with heterotrophic and chemoautotrophic metabolism surpassed the estimated supply of oxygen to SLW, implying that microbial activity could deplete the oxygenated waters, resulting in anoxia. We used thermodynamic calculations to examine the biogeochemical and energetic consequences of environmentally imposed switching between aerobic and anaerobic metabolisms

  18. Combining nonthermal technologies to control foodborne microorganisms.

    Science.gov (United States)

    Ross, Alexander I V; Griffiths, Mansel W; Mittal, Gauri S; Deeth, Hilton C

    2003-12-31

    Novel nonthermal processes, such as high hydrostatic pressure (HHP), pulsed electric fields (PEFs), ionizing radiation and ultrasonication, are able to inactivate microorganisms at ambient or sublethal temperatures. Many of these processes require very high treatment intensities, however, to achieve adequate microbial destruction in low-acid foods. Combining nonthermal processes with conventional preservation methods enhances their antimicrobial effect so that lower process intensities can be used. Combining two or more nonthermal processes can also enhance microbial inactivation and allow the use of lower individual treatment intensities. For conventional preservation treatments, optimal microbial control is achieved through the hurdle concept, with synergistic effects resulting from different components of the microbial cell being targeted simultaneously. The mechanisms of inactivation by nonthermal processes are still unclear; thus, the bases of synergistic combinations remain speculative. This paper reviews literature on the antimicrobial efficiencies of nonthermal processes combined with conventional and novel nonthermal technologies. Where possible, the proposed mechanisms of synergy is mentioned.

  19. Heterogeneity in isogenic populations of microorganisms

    DEFF Research Database (Denmark)

    Pedersen, Anne Egholm

    heterogeneity was detected when the culture had been propagated according to the guidelines of the Copenhagen School of Bacterial Growth Physiology. The L. lactis GFP reporter strain was more challenging to analyze. The population profile for this reporter strain was shown to be dependent on the type of medium...... values for quantifiable variables are used. The reproducibility of an experiment could thus be affected by the presence of subpopulations or high levels of phenotypic variations. Ole Maaløe and colleagues did in the late 1950’ties observe that the growth rate, RNA, DNA and protein synthesis and cell...... factor per unit of time. The use of a balanced growing culture is a cornerstone in the Copenhagen School of Bacterial Growth Physiology headed by Ole Maaløe. Due to the size of the microorganism it is challenging to measure a quantifiable variable in a single cell. However, fluorescence, whether being...

  20. Responsive Polydiacetylene Vesicles for Biosensing Microorganisms

    Directory of Open Access Journals (Sweden)

    Estelle Lebègue

    2018-02-01

    Full Text Available Polydiacetylene (PDA inserted in films or in vesicles has received increasing attention due to its property to undergo a blue-to-red colorimetric transition along with a change from non-fluorescent to fluorescent upon application of various stimuli. In this review paper, the principle for the detection of various microorganisms (bacteria, directly detected or detected through the emitted toxins or through their DNA, and viruses and of antibacterial and antiviral peptides based on these responsive PDA vesicles are detailed. The analytical performances obtained, when vesicles are in suspension or immobilized, are given and compared to those of the responsive vesicles mainly based on the vesicle encapsulation method. Many future challenges are then discussed.

  1. Pathogenic microorganisms of medicinal herbal drugs

    Directory of Open Access Journals (Sweden)

    Stević Tatjana

    2012-01-01

    Full Text Available All the parts of plants (root, leaf, flower naturally have a high level of microorganisms, bacteria and fungi, especially molds. Microbial contamination could be a result of inappropriate harvesting, cleaning of the raw plant material, unhygienic processing of the plants, unsuitable transport and storage. After examination of over 40 dried medicinal plant species, the lowest microbial quality was determined for Maydis stigma, Mentha leaf and herb, Equisetum herb, Calendula flower, Urtica leaf, Melissa leaf, Serpylli herb, Chamomilla flower etc. Although mixed infections are recorded with different types of fungus, Fusarium was observed as the most dominant genus in most of the tested drugs, followed by Aspergillus and Alternaria. In addition to these fungi species from the following genera were identified: Phoma, Cephalosporium, Nigrospora, Cladosporium, Epicoccum, Gliocladium, Myrothecium, Cercospora, Phomopsis, Verticillium, Dreschlera (=Bipolaris, Rhizoctonia, Septoria, Trichoderma, Curvularia, Stachybotrys, Trichothecium, Puccinia, Botrytis, Mucor and Rhizopus sp., depending on plant species.

  2. Synthetic biology expands chemical control of microorganisms.

    Science.gov (United States)

    Ford, Tyler J; Silver, Pamela A

    2015-10-01

    The tools of synthetic biology allow researchers to change the ways engineered organisms respond to chemical stimuli. Decades of basic biology research and new efforts in computational protein and RNA design have led to the development of small molecule sensors that can be used to alter organism function. These new functions leap beyond the natural propensities of the engineered organisms. They can range from simple fluorescence or growth reporting to pathogen killing, and can involve metabolic coordination among multiple cells or organisms. Herein, we discuss how synthetic biology alters microorganisms' responses to chemical stimuli resulting in the development of microbes as toxicity sensors, disease treatments, and chemical factories. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Genetic engineering of microorganisms for biodiesel production

    Science.gov (United States)

    Lin, Hui; Wang, Qun; Shen, Qi; Zhan, Jumei; Zhao, Yuhua

    2013-01-01

    Biodiesel, as one type of renewable energy, is an ideal substitute for petroleum-based diesel fuel and is usually made from triacylglycerides by transesterification with alcohols. Biodiesel production based on microbial fermentation aiming to establish more efficient, less-cost and sustainable biodiesel production strategies is under current investigation by various start-up biotechnology companies and research centers. Genetic engineering plays a key role in the transformation of microbes into the desired cell factories with high efficiency of biodiesel production. Here, we present an overview of principal microorganisms used in the microbial biodiesel production and recent advances in metabolic engineering for the modification required. Overexpression or deletion of the related enzymes for de novo synthesis of biodiesel is highlighted with relevant examples. PMID:23222170

  4. Identification of subsurface microorganisms at Yucca Mountain

    International Nuclear Information System (INIS)

    Stetzenbach, L.D.

    1994-01-01

    Bacteria isolated from ground water samples taken from 31 springs during 1993 were collected and processed according to procedures described in earlier reports. These procedures required aseptic collection of surface water samples in sterile screw-capped containers, transportation to the HRC microbiology laboratory, and culture by spread plating onto R2A medium. The isolates were further processed for identification using a gas chromatographic analysis of fatty acid methyl esters (FAME) extracted from cell membranes. This work generated a presumptive identification of 113 bacterial species distributed among 45 genera using a database obtained from Microbial ID, Inc., Newark, Delaware (MIDI). A preliminary examination of the FAME data was accomplished using cluster analysis and principal component analysis software obtained from MIDI. Typically, bacterial strains that cluster at less than 10 Euclidian distance units have fatty acid patterns consistent among members of the same species. Thus an organism obtained from one source can be recognized if it is isolated again from the same or any other source. This makes it possible to track the distribution of organisms and monitor environmental conditions or fluid transport mechanisms. Microorganisms are seldom found as monocultures in natural environments. They are more likely to be closely associated with other genera with complementary metabolic requirements. An understanding of the indigenous microorganism population is useful in understanding subtle changes in the environment. However, classification of environmental organisms using traditional methods is not ideal because differentiation of species with small variations or genera with very similar taxonomic characteristics is beyond the capabilities of traditional microbiological methods

  5. Interactions of phytoplankton, zooplankton and microorganisms

    Science.gov (United States)

    Pomeroy, L. R.; Paffenhöfer, G.-A.; Yoder, J. A.

    We present evidence that there are significant interactions between heterotrophic microorganisms, doliolids and Fritillaria within intrusions of nutrient-rich Gulf Stream water stranding on the continental shelf. During the summer of 1981 cold, nutrient-rich water from below the surface of the Gulf Stream was repeatedly intruded and stranded on the continental shelf off northeastern Florida. On August 6 old, stranded Gulf Stream water depleted of nitrate occupied the lower layer on the outer shelf. The upper water was continental shelf water, older but of undefined age. On August 6 free-living bacteria were >10 6ml -1 everywhere at all depths, an order of magnitude greater than normal bacterial numbers on the northeastern Florida continental shelf. Over 10 days the numbers of free bacteria doubled while bacteria attached to particles increased by a factor of four. The adenylate/chlorophyll ratio showed that phytoplankton dominated the lower layers of intruded water, while the surface water became increasingly dominated by heterotrophic microorganisms (bacteria and protozoa) over 10 days. There were significant, negative correlations between bacteria and doliolids and between bacteria and Fritillaria. Regions of maximum bacterial numbers did not coincide with locations of salp swarms. The increased numbers of bacteria at all depths in a highly stratified system in which most phytoplankton are in the lower layer suggests a diverse source of bacterial growth substrates, some of which involve zooplankton as intermediaries. Production of autotrophs is more than twice that of microheterotrophs on average, but because of their differential distribution, microheterotrophs are the dominant biomass in much of the surface water and may be significant in energy flux to metazoan consumers as well as competitors for mutually useable sources of nutrition.

  6. System for identification of microorganism and detection of infectious disorder

    DEFF Research Database (Denmark)

    2013-01-01

    Methods for the identification of microorganisms or infectious disorders are disclosed, comprising obtaining a suitable sample from sources such as persons, animals, plants, food, water or soil. The methods also comprise providing tailored nucleic acid substrate(s) designed to react with a type 1...... topoisomerase from one or more microorganism(s) or infectious agent(s), and incubating said substrate with said sample, or extracts or preparations from the sample, so that the substrate is processed by said topoisomerase if said microorganism(s) or infectious agent(s) is present in the sample. Finally......, processed substrates are identified and potentially quantified by one or more of a range of standard molecular biology methods and read-out systems. The identification and potential quantification of microorganisms and infectious agents, including but not limited to Plasmodium falciparum and Mycobacterium...

  7. Ocean Prediction Center

    Science.gov (United States)

    Social Media Facebook Twitter YouTube Search Search For Go NWS All NOAA Weather Analysis & Forecasts of Commerce Ocean Prediction Center National Oceanic and Atmospheric Administration Analysis & Unified Surface Analysis Ocean Ocean Products Ice & Icebergs NIC Ice Products NAIS Iceberg Analysis

  8. Transcriptional patterns identify resource controls on the diazotroph Trichodesmium in the Atlantic and Pacific oceans.

    Science.gov (United States)

    Rouco, Mónica; Frischkorn, Kyle R; Haley, Sheean T; Alexander, Harriet; Dyhrman, Sonya T

    2018-02-28

    The N 2 -fixing cyanobacterium Trichodesmium is intensely studied because of the control this organism exerts over the cycling of carbon and nitrogen in the low nutrient ocean gyres. Although iron (Fe) and phosphorus (P) bioavailability are thought to be major drivers of Trichodesmium distributions and activities, identifying resource controls on Trichodesmium is challenging, as Fe and P are often organically complexed and their bioavailability to a single species in a mixed community is difficult to constrain. Further, Fe and P geochemistries are linked through the activities of metalloenzymes, such as the alkaline phosphatases (APs) PhoX and PhoA, which are used by microbes to access dissolved organic P (DOP). Here we identified significant correlations between Trichodesmium-specific transcriptional patterns in the North Atlantic (NASG) and North Pacific Subtropical Gyres (NPSG) and patterns in Fe and P biogeochemistry, with the relative enrichment of Fe stress markers in the NPSG, and P stress markers in the NASG. We also observed the differential enrichment of Fe-requiring PhoX transcripts in the NASG and Fe-insensitive PhoA transcripts in the NPSG, suggesting that metalloenzyme switching may be used to mitigate Fe limitation of DOP metabolism in Trichodesmium. This trait may underpin Trichodesmium success across disparate ecosystems.

  9. Biological nitrogen fixation in the oxygen-minimum region of the eastern tropical North Pacific ocean.

    Science.gov (United States)

    Jayakumar, Amal; Chang, Bonnie X; Widner, Brittany; Bernhardt, Peter; Mulholland, Margaret R; Ward, Bess B

    2017-10-01

    Biological nitrogen fixation (BNF) was investigated above and within the oxygen-depleted waters of the oxygen-minimum zone of the Eastern Tropical North Pacific Ocean. BNF rates were estimated using an isotope tracer method that overcame the uncertainty of the conventional bubble method by directly measuring the tracer enrichment during the incubations. Highest rates of BNF (~4 nM day -1 ) occurred in coastal surface waters and lowest detectable rates (~0.2 nM day -1 ) were found in the anoxic region of offshore stations. BNF was not detectable in most samples from oxygen-depleted waters. The composition of the N 2 -fixing assemblage was investigated by sequencing of nifH genes. The diazotrophic assemblage in surface waters contained mainly Proteobacterial sequences (Cluster I nifH), while both Proteobacterial sequences and sequences with high identities to those of anaerobic microbes characterized as Clusters III and IV type nifH sequences were found in the anoxic waters. Our results indicate modest input of N through BNF in oxygen-depleted zones mainly due to the activity of proteobacterial diazotrophs.

  10. Millimeter-Sized Marine Plastics: A New Pelagic Habitat for Microorganisms and Invertebrates

    Science.gov (United States)

    Reisser, Julia; Shaw, Jeremy; Hallegraeff, Gustaaf; Proietti, Maira; Barnes, David K. A.; Thums, Michele; Wilcox, Chris; Hardesty, Britta Denise; Pattiaratchi, Charitha

    2014-01-01

    Millimeter-sized plastics are abundant in most marine surface waters, and known to carry fouling organisms that potentially play key roles in the fate and ecological impacts of plastic pollution. In this study we used scanning electron microscopy to characterize biodiversity of organisms on the surface of 68 small floating plastics (length range = 1.7–24.3 mm, median = 3.2 mm) from Australia-wide coastal and oceanic, tropical to temperate sample collections. Diatoms were the most diverse group of plastic colonizers, represented by 14 genera. We also recorded ‘epiplastic’ coccolithophores (7 genera), bryozoans, barnacles (Lepas spp.), a dinoflagellate (Ceratium), an isopod (Asellota), a marine worm, marine insect eggs (Halobates sp.), as well as rounded, elongated, and spiral cells putatively identified as bacteria, cyanobacteria, and fungi. Furthermore, we observed a variety of plastic surface microtextures, including pits and grooves conforming to the shape of microorganisms, suggesting that biota may play an important role in plastic degradation. This study highlights how anthropogenic millimeter-sized polymers have created a new pelagic habitat for microorganisms and invertebrates. The ecological ramifications of this phenomenon for marine organism dispersal, ocean productivity, and biotransfer of plastic-associated pollutants, remains to be elucidated. PMID:24941218

  11. Millimeter-sized marine plastics: a new pelagic habitat for microorganisms and invertebrates.

    Directory of Open Access Journals (Sweden)

    Julia Reisser

    Full Text Available Millimeter-sized plastics are abundant in most marine surface waters, and known to carry fouling organisms that potentially play key roles in the fate and ecological impacts of plastic pollution. In this study we used scanning electron microscopy to characterize biodiversity of organisms on the surface of 68 small floating plastics (length range = 1.7-24.3 mm, median = 3.2 mm from Australia-wide coastal and oceanic, tropical to temperate sample collections. Diatoms were the most diverse group of plastic colonizers, represented by 14 genera. We also recorded 'epiplastic' coccolithophores (7 genera, bryozoans, barnacles (Lepas spp., a dinoflagellate (Ceratium, an isopod (Asellota, a marine worm, marine insect eggs (Halobates sp., as well as rounded, elongated, and spiral cells putatively identified as bacteria, cyanobacteria, and fungi. Furthermore, we observed a variety of plastic surface microtextures, including pits and grooves conforming to the shape of microorganisms, suggesting that biota may play an important role in plastic degradation. This study highlights how anthropogenic millimeter-sized polymers have created a new pelagic habitat for microorganisms and invertebrates. The ecological ramifications of this phenomenon for marine organism dispersal, ocean productivity, and biotransfer of plastic-associated pollutants, remains to be elucidated.

  12. Enhancement of uranium-accumulating ability of microorganisms by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sakaguchi, Takashi; Nakajima, Akira; Tsuruta, Takehiko [Miyazaki Medical Coll., Kiyotake (Japan)

    1998-01-01

    Some microorganisms having excellent ability to accumulate uranium were isolated, from soil and water systems in and around the Ningyo-toge Station of Power Reactor and Nuclear Fuel Development Corporation. The enhancement of uranium-accumulating ability of microorganisms by electron-beam irradiation was examined, and the ability of JW-046 was increased 3-5% by the irradiation. The irradiation affect the growth of some of microorganisms tested. (author)

  13. Plasma inactivation of food-related microorganisms in liquids

    International Nuclear Information System (INIS)

    Marsili, Lisa; Espie, Steven; Anderson, J.G.John G.; MacGregor, S.J.Scott J.

    2002-01-01

    This paper reports on a plasma process that inactivates microorganisms in liquids through the application of high-voltage pulses. These pulses result in breakdown of the gas and liquid layers, producing many active species such as UV photons, ozone, free radicals and free electrons. Several test microorganisms representing a range of problematic microorganisms were investigated. Significant reductions in microbial population were achieved, demonstrating the effectiveness of using the plasma discharge process to treat contaminated liquids

  14. Radiation resistance of microorganisms on unsterilized infusion sets

    DEFF Research Database (Denmark)

    Christensen, E. Ahrensburg; Kristensen, H.; Hoborn, J.

    1991-01-01

    Three different methods were used for detecting and isolating microorganisms with high radiation resistance from the microbial contamination on infusion sets prior to sterilization. By all three methods, microorganisms with a radiation resistance high enough to be a critical factor in a steriliza......Three different methods were used for detecting and isolating microorganisms with high radiation resistance from the microbial contamination on infusion sets prior to sterilization. By all three methods, microorganisms with a radiation resistance high enough to be a critical factor...

  15. Esterase screening using whole cells of Brazilian soil microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Mantovani, Simone M.; Oliveira, Luciana G. de; Marsaioli, Anita J., E-mail: anita@iqm.unicamp.b [Universidade Estadual de Campinas (IQ/UNICAMP), SP (Brazil). Inst. de Quimica

    2010-07-01

    A miniaturized enzymatic assay using fluorescent probes to reveal esterase producing microorganisms was optimized and applied to screen 64 soil bacterial strains. The best results were validated using traditional non-fluorogenic assays with acetyl and propanoyl phenylethanol to confirm the miniaturized results. The most active microorganisms belong to the genus Bacillus showing esterase activity and good enantiomeric ratios for the resolution of phenylethanol derivatives (E > 30). Part of the microorganisms are kept in our laboratory in glycerol or freezedried and the best microorganisms will be deposited in the CBMAI/CPQBA/UNICAMP culture collection. (author)

  16. [Characteristics of proteins synthesized by hydrogen-oxidizing microorganisms].

    Science.gov (United States)

    Volova, T G; Barashkov, V A

    2010-01-01

    The study was conducted to determine the biological value of proteins synthesized by hydrogen-oxidizing microorganisms--the hydrogen bacteria Alcaligenes eutrophus Z1 and Ralstonia eutropha B5786 and the CO-resistant strain of carboxydobacterium Seliberia carboxydohydrogena Z1062. Based on a number of significant parameters characterizing the biological value of a product, the proteins of hydrogen-oxidizing microorganisms have been found to occupy an intermediate position between traditional animal and plant proteins. The high total protein in biomass of these microorganisms, their complete amino acid content, and availability to proteolytic enzymes allow for us to consider these microorganisms as potential protein producers.

  17. Bioremediation of Industrial Waste Through Enzyme Producing Marine Microorganisms.

    Science.gov (United States)

    Sivaperumal, P; Kamala, K; Rajaram, R

    Bioremediation process using microorganisms is a kind of nature-friendly and cost-effective clean green technology. Recently, biodegradation of industrial wastes using enzymes from marine microorganisms has been reported worldwide. The prospectus research activity in remediation area would contribute toward the development of advanced bioprocess technology. To minimize industrial wastes, marine enzymes could constitute a novel alternative in terms of waste treatment. Nowadays, the evidence on the mechanisms of bioremediation-related enzymes from marine microorganisms has been extensively studied. This review also will provide information about enzymes from various marine microorganisms and their complexity in the biodegradation of comprehensive range of industrial wastes. © 2017 Elsevier Inc. All rights reserved.

  18. Studying ocean acidification in the Arctic Ocean

    Science.gov (United States)

    Robbins, Lisa

    2012-01-01

    The U.S. Geological Survey (USGS) partnership with the U.S. Coast Guard Ice Breaker Healey and its United Nations Convention Law of the Sea (UNCLOS) cruises has produced new synoptic data from samples collected in the Arctic Ocean and insights into the patterns and extent of ocean acidification. This framework of foundational geochemical information will help inform our understanding of potential risks to Arctic resources due to ocean acidification.

  19. Glyphosate-Degrading Microorganisms from Industrial Activated Sludge

    OpenAIRE

    Balthazor, Terry M.; Hallas, Laurence E.

    1986-01-01

    A plating medium was developed to isolate N-phosphonomethylglycine (glyphosate)-degrading microorganisms, with glyphosate as the sole phosphorus source. Two industrial biosystems treating glyphosate wastes contained elevated microbial counts on the medium. One purified isolate metabolized glyphosate to aminomethylphosphonic acid, mineralizing this accumulating intermediate during log growth. This microorganism has been identified as a Flavobacterium species.

  20. Microorganisms associated with the spoilage of avocado pear ...

    African Journals Online (AJOL)

    The microorganisms associated with the spoilage of Avocado pear, Persea americana fruits, purchased fresh from various markets in Benin City were investigated. The pour plate method was used for the isolation. A total of nine species of microorganisms were isolated and identified in this study. They comprise of seven ...

  1. the economic importance of microorganism in food processing

    African Journals Online (AJOL)

    BSN

    This paper attempts to highlight the Economic Importance of microorganisms in food processing and manufacturing; it goes further to differentiate between the desirable ... Desirable importance are those cost saving and revenue generating activities ... Microorganism (yeast) play very useful role in the Bakery industries.

  2. Gut Microorganisms Found Necessary for Successful Cancer Therapy | Poster

    Science.gov (United States)

    By Nancy Parrish, Staff Writer Humans play host to trillions of microorganisms that help our bodies perform basic functions, like digestion, growth, and fighting disease. In fact, bacterial cells outnumber the human cells in our bodies by 10 to 1.1 The tens of trillions of microorganisms thriving in our intestines are known as gut microbiota, and those that are not harmful to

  3. 78 FR 42451 - Animal Feeds Contaminated With Salmonella Microorganisms

    Science.gov (United States)

    2013-07-16

    .... FDA-2013-N-0253] Animal Feeds Contaminated With Salmonella Microorganisms AGENCY: Food and Drug... revoking an advisory opinion on animal feeds contaminated with Salmonella microorganisms. This action is... articulated in a final compliance policy guide (CPG) on Salmonella in food for animals. DATES: This rule is...

  4. Effects of heat-activated persulfate oxidation on soil microorganisms

    DEFF Research Database (Denmark)

    Tsitonaki, Aikaterini; Smets, Barth F.; Bjerg, Poul Løgstrup

    2008-01-01

    /L). The results emphasize the necessity of using multiple toxicity assays and indigenous cultures in order to realistically assess the potential effects of in situ chemical oxidation on soil microorganisms. A comparison to other studies suggests that the effects of activated persulfate on soil microorganisms...

  5. Titanium photocatalyst against human pathogenic microorganisms

    International Nuclear Information System (INIS)

    Kussovski, V.; Stefchev, P.; Kirilov, R.

    2011-01-01

    The conventional methods of disinfection are not effective in the longer term. They are time and staff intensive and use aggressive chemicals. Photocatalytic oxidation on surfaces coated with titanium dioxide (TiO 2 ) might offer a possible alternative. The antimicrobial activity of TiO 2 powder P25 and thin films of TiO 2 on glass slides against representative strains of microorganisms associated with hospital-acquired infections (Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans) was investigated in vitro. High efficiency has been found in the case of the studied bacterial strains, particularly for the P. aeruginosa. It was shown that it is possible to disinfect surfaces coated with TiO 2 and stimulated by UV-A light. The reduction efficiencies for P. aeruginosa, S. aureus and C. albicans were 3.19, 2.32 and 1.22. In all cases sublethal UV-A doses provoked an important lethality in the presence of TiO 2 . (authors)

  6. Heavy metal removal and recovery using microorganisms

    International Nuclear Information System (INIS)

    Wilde, E.W.; Benemann, J.R.

    1991-02-01

    Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding

  7. Peat soils stabilization using Effective Microorganisms (EM)

    Science.gov (United States)

    Yusof, N. Z.; Samsuddin, N. S.; Hanif, M. F.; Syed Osman, S. B.

    2018-04-01

    Peat soil is known as geotechnical problematic soil since it is the softest soil having highly organic and moisture content which led to high compressibility, low shear strength and long-term settlement. The aim of this study was to obtain the stabilized peat soils using the Effective Microorganisms (EM). The volume of EM added and mixed with peat soils varied with 2%, 4%, 6%, 8% and 10% and then were cured for 7, 14 and 21 days. The experiment was done for uncontrolled and controlled moisture content. Prior conducting the main experiments, the physical properties such as moisture content, liquid limit, specific gravity, and plastic limit etc. were measure for raw peat samples. The Unconfined Compressive Strength (UCS) test was performed followed by regression analysis to check the effect of EM on the soil strength. Obtained results have shown that the mix design for controlled moisture contents showed the promising improvement in their compressive strength. The peat soil samples with 10% of EM shows the highest increment in UCS value and the percentage of increments are in the range of 44% to 65% after curing for 21 days. The regression analysis of the EM with the soil compressive strength showed that in controlled moisture conditions, EM significantly improved the soil stability as the value of R2 ranged between 0.97 – 0.78. The results have indicated that the addition of EM in peat soils provides significant improving in the strength of the soil as well as the other engineering properties.

  8. Heavy metal removal and recovery using microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, E.W. (Westinghouse Savannah River Co., Aiken, SC (United States)); Benemann, J.R. (Benemann (J.R.), Pinole, CA (United States))

    1991-02-01

    Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding.

  9. Snow as a habitat for microorganisms

    Science.gov (United States)

    Hoham, Ronald W.

    1989-01-01

    There are three major habitats involving ice and snow, and the microorganisms studied from these habitats are most eukaryotic. Sea ice is inhabited by algae called diatoms, glacial ice has sparse populations of green algai cal desmids, and the temporary and permanent snows in mountainous regions and high latitudes are inhabited mostly by green algal flagellates. The life cycle of green algal flagellates is summarized by discussing the effects of light, temperature, nutrients, and snow melts. Specific examples of optimal conditions and environmental effects for various snow algae are given. It is not likely that the eukaryotic snow algae presented are candidated for life on the planet Mars. Evolutionally, eukaryotic cells as know on Earth may not have had the opportunity to develop on Mars (if life evolved at all on Mars) since eukaryotes did not appear on Earth until almost two billion years after the first prokaryotic organisms. However, the snow/ice ecosystems on Earth present themselves as extreme habitats were there is evidence of prokaryotic life (eubacteria and cyanbacteria) of which literally nothing is known. Any future surveillances of extant and/or extinct life on Mars should include probes (if not landing sites) to investigate sites of concentrations of ice water. The possibility of signs of life in Martian polar regions should not be overlooked.

  10. Cyanide utilization and degradation by microorganisms.

    Science.gov (United States)

    Knowles, C J

    1988-01-01

    Various microorganisms can produce (cyanogenesis) or degrade cyanide. They degrade cyanide either to detoxify it, or to use it as a source of nitrogen for growth. Significant amounts of cyanide are formed as a secondary metabolite by a wide range of fungi and a few bacteria by decarboxylation of glycine. When cyanide has been formed by the snow mould fungus it is degraded by conversion to carbon dioxide and ammonia via an unknown pathway. In contrast, cyanogenic bacteria either do not further catabolize cyanide or they convert it into beta-cyanoalanine by addition to cysteine or O-acetylserine. Several non-cyanogenic fungi that are pathogens of cyanogenic plants are known to degrade cyanide by hydration to formamide by the enzyme cyanide hydratase. Such fungi can be immobilized and used in packed-cell columns to continuously detoxify cyanide. ICI Biological Products Business market a preparation of spray-dried fungal mycelia, 'CYCLEAR', to detoxify industrial wastes. Novo Industri have also introduced a cyanidase preparation to convert cyanide directly into formate and ammonia. Bacteria have been isolated that use cyanide as a source of nitrogen for growth. Because cyanide, as KCN or NaCN, is toxic for growth, the bacteria (Pseudomonas fluorescens) have to be grown in fed-batch culture with cyanide as the limiting nutrient. Cyanide is converted to carbon dioxide and ammonia (which is then assimilated) by an NADH-linked cyanide oxygenase system.

  11. Tracking microorganisms and gene in the environment

    International Nuclear Information System (INIS)

    Atlas, R.M.; Sayler, G.S.

    1988-01-01

    Studies have been conducted to determine the sensitivities and limitations of various methods for determining the fate of genetically engineered microorganisms (GEMs) and their genes in the environment. Selective viable plate count procedures can be designed to detect the introduced organisms with high sensitivity; but they are restricted by potential mutations affecting the expression of the selective characteristic in the introduced organism, the occurrence of the particular selective characteristic in the indigenous organisms, and the need to culture the organism. The accuracy of this approach is greatly improved by colony hybridization procedures that use a specific gene probe to detect the introduced genes, but this approach is still only as sensitive as the plating procedure. Direct extraction of DNA from environmental samples, coupled with dot blot hybridization with radiolabeled probe DNA or solution hybridization, gives a high degree of both sensitivity and precision. This approach does not require culturing of the organism; and even if an introduced gene moves into a new organism or if the introduced organism is viable but nonculturable, the gene probe methods will detect the persistence of the introduced genes in the environment. Efficient direct DNA extraction methods have been developed and tested following in vitro experimental additions of GEMs to sediment and water samples

  12. Dynamic size spectrometry of airborne microorganisms: Laboratory evaluation and calibration

    Science.gov (United States)

    Qian, Yinge; Willeke, Klaus; Ulevicius, Vidmantas; Grinshpun, Sergey A.; Donnelly, Jean

    Bioaerosol samplers need to be calibrated for the microorganisms of interest. The Aerosizer, a relatively new aerodynamic size spectrometer, is shown to be a suitable dynamic instrument for the evaluation and calibration of such samplers in the laboratory, prior to their use in the field. It provides the necessary reference count against which the microbiological response of the sampler can be compared. It measures the health-significant aerodynamic diameters of microorganisms down to 0.5 μm, thus including most of the bacteria, fungi and pollen found in outdoor and indoor air environments. Comparison tests with a laser size spectrometer indicate that the suspension of microorganisms needs to be washed several times before aerosolization to avoid coating of the airborne microorganisms with nutrients and microbial slime from the suspension, and to reduce the residue particles to sizes below the lowest size of the aerosolized microorganisms.

  13. Biodiesel production by various oleaginous microorganisms from organic wastes.

    Science.gov (United States)

    Cho, Hyun Uk; Park, Jong Moon

    2018-05-01

    Biodiesel is a biodegradable and renewable fuel. A large amount of research has considered microbial oil production using oleaginous microorganisms, but the commercialization of microbial lipids produced in this way remains uncertain due to the high cost of feedstock or low lipid yield. Microbial lipids can be typically produced by microalgae, yeasts, and bacteria; the lipid yields of these microorganisms can be improved by using sufficient concentrations of organic carbon sources. Therefore, combining low-cost organic compounds contained in organic wastes with cultivation of oleaginous microorganisms can be a promising approach to obtain commercial viability. However, to achieve effective bioconversion of low-cost substrates to microbial lipids, the characteristics of each microorganism and each substrate should be considered simultaneously. This article discusses recent approaches to developing cost-effective microbial lipid production processes that use various oleaginous microorganisms and organic wastes. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Modelling and application of the inactivation of microorganism

    International Nuclear Information System (INIS)

    Oğuzhan, P.; Yangılar, F.

    2013-01-01

    Prevention of consuming contaminated food with toxic microorganisms causing infections and consideration of food protection and new microbial inactivation methods are obligatory situations. Food microbiology is mainly related with unwanted microorganisms spoiling foods during processing and transporting stages and causing diseases. Determination of pathogen microorganisms is important for human health to define and prevent dangers and elongate shelf life. Inactivation of pathogen microorganisms can provide food security and reduce nutrient losses. Microbial inactivation which is using methods of food protection such as food safety and fresh. With this aim, various methods are used such as classical thermal processes (pasteurisation, sterilisation), pressured electrical field (PEF), ionised radiation, high pressure, ultrasonic waves and plasma sterilisation. Microbial inactivation modelling is a secure and effective method in food production. A new microbiological application can give useful results for risk assessment in food, inactivation of microorganisms and improvement of shelf life. Application and control methods should be developed and supported by scientific research and industrial applications

  15. The Ocean Literacy Campaign

    Science.gov (United States)

    Schoedinger, S. E.; Strang, C.

    2008-12-01

    "Ocean Literacy is an understanding of the ocean's influence on you and your influence on the ocean." This simple statement captures the spirit of a conceptual framework supporting ocean literacy (COSEE et al., 2005). The framework comprises 7 essential principles and 44 fundamental concepts an ocean literate person would know (COSEE et al., 2005). The framework is the result of an extensive grassroots effort to reach consensus on (1) a definition for ocean literacy and (2) an articulation of the most important concepts to be understood by ocean-literate citizen (Cava et al., 2005). In the process of reaching consensus on these "big ideas" about the ocean, what began as a series of workshops has emerged as a campaign "owned" by an ever-expanding community of individuals, organizations and networks involved in developing and promoting the framework. The Ocean Literacy Framework has provided a common language for scientists and educators working together and serves as key guidance for the ocean science education efforts. This presentation will focus on the impact this Ocean Literacy Campaign has had to date as well as efforts underway to provide additional tools to enable educators and educational policy makers to further integrate teaching and learning about the ocean and our coasts into formal K-12 education and informal education. COSEE, National Geographic Society, NOAA, College of Exploration (2005). Ocean Literacy: The Essential Principles of Ocean Sciences Grades K-12, a jointly published brochure, URL: http://www.coexploration.org/oceanliteracy/documents/OceanLitChart.pdf Cava, F., S. Schoedinger , C. Strang, and P. Tuddenham (2005). Science Content and Standards for Ocean Literacy: A Report on Ocean Literacy, URL: http://www.coexploration.org/oceanliteracy/documents/OLit2004-05_Final_Report.pdf.

  16. 75 FR 18778 - Safety Zone; Ocean City Air Show 2010, Atlantic Ocean, Ocean City, MD

    Science.gov (United States)

    2010-04-13

    ...-AA00 Safety Zone; Ocean City Air Show 2010, Atlantic Ocean, Ocean City, MD AGENCY: Coast Guard, DHS... zone on the Atlantic Ocean in the vicinity of Ocean City, Maryland to support the Ocean City Air Show. This action is intended to restrict vessel traffic movement on the Atlantic Ocean to protect mariners...

  17. Ocean Disposal Site Monitoring

    Science.gov (United States)

    EPA is responsible for managing all designated ocean disposal sites. Surveys are conducted to identify appropriate locations for ocean disposal sites and to monitor the impacts of regulated dumping at the disposal sites.

  18. People and Oceans.

    Science.gov (United States)

    NatureScope, 1988

    1988-01-01

    Discusses people's relationship with oceans, focusing on ocean pollution, use, and protective measures of the sea and its wildlife. Activities included are "Mythical Monsters"; "Globetrotters"; "Plastic in the Sea"; and "Sea of Many Uses." (RT)

  19. Ocean Sediment Thickness Contours

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ocean sediment thickness contours in 200 meter intervals for water depths ranging from 0 - 18,000 meters. These contours were derived from a global sediment...

  20. Ocean Robotic Networks

    Energy Technology Data Exchange (ETDEWEB)

    Schofield, Oscar [Rutgers University

    2012-05-23

    We live on an ocean planet which is central to regulating the Earth’s climate and human society. Despite the importance of understanding the processes operating in the ocean, it remains chronically undersampled due to the harsh operating conditions. This is problematic given the limited long term information available about how the ocean is changing. The changes include rising sea level, declining sea ice, ocean acidification, and the decline of mega fauna. While the changes are daunting, oceanography is in the midst of a technical revolution with the expansion of numerical modeling techniques, combined with ocean robotics. Operating together, these systems represent a new generation of ocean observatories. I will review the evolution of these ocean observatories and provide a few case examples of the science that they enable, spanning from the waters offshore New Jersey to the remote waters of the Southern Ocean.

  1. Ocean Uses: California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Ocean Uses Atlas Project is an innovative partnership between NOAA's National Marine Protected Areas Center and Marine Conservation Biology Institute. The...

  2. Ethane ocean on Titan

    Science.gov (United States)

    Lunine, J. I.; Stevenson, D. J.; Yung, Y.L.

    1983-01-01

    Voyager I radio occultation data is employed to develop a qualitative model of an ethane ocean on Titan. It is suggested that the ocean contains 25 percent CH4 and that the ocean is in dynamic equilibrium with an N2 atmosphere. Previous models of a CH4 ocean are discounted due to photolysis rates of CH4 gas. Tidal damping of Titan's orbital eccentricity is taken as evidence for an ocean layer approximately 1 km deep, with the ocean floor being covered with a solid C2H2 layer 100 to 200 m thick. The photolytic process disrupting the CH4, if the estimates of the oceanic content of CH4 are correct, could continue for at least one billion years. Verification of the model is dependent on detecting CH4 clouds in the lower atmosphere, finding C2H6 saturation in the lower troposphere, or obtaining evidence of a global ocean.

  3. Regional Ocean Data Assimilation

    KAUST Repository

    Edwards, Christopher A.; Moore, Andrew M.; Hoteit, Ibrahim; Cornuelle, Bruce D.

    2015-01-01

    This article reviews the past 15 years of developments in regional ocean data assimilation. A variety of scientific, management, and safety-related objectives motivate marine scientists to characterize many ocean environments, including coastal

  4. Ocean Disposal Sites

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 1972, Congress enacted the Marine Protection, Research, and Sanctuaries Act (MPRSA, also known as the Ocean Dumping Act) to prohibit the dumping of material into...

  5. Ocean Station Vessel

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ocean Station Vessels (OSV) or Weather Ships captured atmospheric conditions while being stationed continuously in a single location. While While most of the...

  6. California Ocean Uses Atlas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a result of the California Ocean Uses Atlas Project: a collaboration between NOAA's National Marine Protected Areas Center and Marine Conservation...

  7. Ocean Acidification Product Suite

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Scientists within the ACCRETE (Acidification, Climate, and Coral Reef Ecosystems Team) Lab of AOML_s Ocean Chemistry and Ecosystems Division (OCED) have constructed...

  8. Formation of methylamine by rumen microorganisms

    International Nuclear Information System (INIS)

    Itabashi, Hisao; Kandatsu, Makoto.

    1978-01-01

    An unknown ninhydrin positive peak on the chromatograms of amino acid analyzer of alkalified rumen fluid distillate of goats was isolated as DNP-derivative and identified as methylamine. Under normal feeding condition, its concentration in the rumen ranged 0.1-3.9 mgN/100 ml of rumen fluid and the proportion of methylamine in total volatile base, or apparent ammonia, ranged 0.5-13% during post-feeding. When ammonium salt was administered into the rumen with hay-concentrate ration, these values were increased up to 8.1 mgN/100 ml and 25.8% respectively. Concentrations of ammonia and methylamine when aspartic acid or alanine was administered into the rumen in place of concentrate mixture (control) were not markedly different from the control. In the case of arginine, glutamic acid or glycine administration, these concentrations were depressed as compared to the control. There were no distinct differences in the concentration of methylamine between the faunated and unfaunated goats. 14 C from 14 C-chlorella protein hydrolyzates, U- 14 C-alanine, 2- 14 C-glycine or 14 C-sodium bicarbonate was incorporated into methylamine in invitro incubation with rumen micro-organisms. When the washed suspensions of rumen bacteria or protozoa were incubated with 14 C-chlorella protein hydrolyzates, the radioactivity in methylamine appeared only in the case of bacteria suspensions. After the addition of 15 N-ammonium citrate into the rumen, the incorporation of 15 N into methylamine was observed during 1-9 hr. (auth.)

  9. Biodegradation of hexachlorocyclohexane (HCH) by microorganisms.

    Science.gov (United States)

    Phillips, Theresa M; Seech, Alan G; Lee, Hung; Trevors, Jack T

    2005-08-01

    The organochlorine pesticide Lindane is the gamma-isomer of hexachlorocyclohexane (HCH). Technical grade Lindane contains a mixture of HCH isomers which include not only gamma-HCH, but also large amounts of predominantly alpha-, beta- and delta-HCH. The physical properties and persistence of each isomer differ because of the different chlorine atom orientations on each molecule (axial or equatorial). However, all four isomers are considered toxic and recalcitrant worldwide pollutants. Biodegradation of HCH has been studied in soil, slurry and culture media but very little information exists on in situ bioremediation of the different isomers including Lindane itself, at full scale. Several soil microorganisms capable of degrading, and utilizing HCH as a carbon source, have been reported. In selected bacterial strains, the genes encoding the enzymes involved in the initial degradation of Lindane have been cloned, sequenced, expressed and the gene products characterized. HCH is biodegradable under both oxic and anoxic conditions, although mineralization is generally observed only in oxic systems. As is found for most organic compounds, HCH degradation in soil occurs at moderate temperatures and at near neutral pH. HCH biodegradation in soil has been reported at both low and high (saturated) moisture contents. Soil texture and organic matter appear to influence degradation presumably by sorption mechanisms and impact on moisture retention, bacterial growth and pH. Most studies report on the biodegradation of relatively low (< 500 mg/kg) concentrations of HCH in soil. Information on the effects of inorganic nutrients, organic carbon sources or other soil amendments is scattered and inconclusive. More in-depth assessments of amendment effects and evaluation of bioremediation protocols, on a large scale, using soil with high HCH concentrations, are needed.

  10. Autecology of microorganisms of typical Ecuador biotopes.

    Science.gov (United States)

    Tashyrev, O B; Pidgorskyi, V S; Toro, Miguel Naranjo; Gualoto, Miguel; Gladka, G V; Tashyreva, H O; Rokitko, P V; Romanovskaya, V A

    2014-01-01

    34 strains of aerobic chemoorganotrophic microorganisms were isolated from 23 soil and plant samples selected from highland biotopes of Ecuador-Andes massif (Papallacta, 4020 m), ash at the foot of the volcano Tungurahua, mountainous jungle (La Favorita, 1600 m), as well as in humid tropic botanical garden (state Puyo, 950 m). In mountain jungle samples the high number of bacteria--10(5)-10(7) CFU/g of sample were represented by 2-5 morphotypes. In highland (4020 m) samples the bacterial counts made from 10(2) to 10(7) CFU/g of sample. The current study describes resistance of isolated strains to high salinity, UV radiation and toxic metal ions. The majority of isolated strains were halotolerant. Isolates from volcanic ash showed high resistance level to UV radiation--LD99,99 made 1000-1440 J/m2; resistance level for isolates from the soil of Puyo Botanical Garden and isolates from rock lichen (Papallacta) LD99,99 made 1160 and 800 J/m2 respectively. Strains isolated from mountain jungle (La Favorita) showed lower UV-resistance. In highland biotopes of Ecuador occurred bacteria resistant to toxic metal ions. The highest resistance to Hg2+ was shown by isolate of lichen from mountain jungle, the maximal growth concentration was 0.025 g/L; to Cr(VI)--by isolate from lichen rock massif--3,0 g/L. Correlation between metal-resistance, halotolerace and UV resistance for studied strains was not detected, probably because of different microbial cell damage/repair mechanisms under the action of these factors.

  11. The interactive microbial ocean

    NARCIS (Netherlands)

    Brussaard, C.P.D.; Bidle, K.D.; Pedrós-Alió, C.; Legrand, C.

    2016-01-01

    Marine microorganisms inhabit diverse environments and interact over different spatial and temporal scales. To fully understand how these interactions shape genome structures, cellular responses, lifestyles, community ecology and biogeochemical cycles, integration of diverse approaches and data is

  12. Nitrogen acquisition by plants and microorganisms in a temperate grassland.

    Science.gov (United States)

    Liu, Qianyuan; Qiao, Na; Xu, Xingliang; Xin, Xiaoping; Han, Jessie Yc; Tian, Yuqiang; Ouyang, Hua; Kuzyakov, Yakov

    2016-03-10

    Nitrogen (N) limitation is common in most terrestrial ecosystems, often leading to strong competition between microorganisms and plants. The mechanisms of niche differentiation to reduce this competition remain unclear. Short-term (15)N experiments with NH4(+), NO3(-), and glycine were conducted in July, August and September in a temperate grassland to evaluate the chemical, spatial and temporal niche differentiation by competition between plants and microorganisms for N. Microorganisms preferred NH4(+) and NO3(-), while plants preferred NO3(-). Both plants and microorganisms acquired more N in August and September than in July. The soil depth had no significant effects on microbial uptake, but significantly affected plant N uptake. Plants acquired 67% of their N from the 0-5 cm soil layer and 33% from the 5-15 cm layer. The amount of N taken up by microorganisms was at least seven times than plants. Although microorganisms efficiently compete for N with plants, the competition is alleviated through chemical partitioning mainly in deeper soil layer. In the upper soil layer, neither chemical nor temporal niche separation is realized leading to strong competition between plants and microorganisms that modifies N dynamics in grasslands.

  13. Analogous nutrient limitations in unicellular diazotrophs and Prochlorococcus in the South Pacific Ocean.

    Science.gov (United States)

    Moisander, Pia H; Zhang, Ruifeng; Boyle, Edward A; Hewson, Ian; Montoya, Joseph P; Zehr, Jonathan P

    2012-04-01

    Growth limitation of phytoplankton and unicellular nitrogen (N(2)) fixers (diazotrophs) were investigated in the oligotrophic Western South Pacific Ocean. Based on change in abundances of nifH or 23S rRNA gene copies during nutrient-enrichment experiments, the factors limiting net growth of the unicellular diazotrophs UCYN-A (Group A), Crocosphaera watsonii, γ-Proteobacterium 24774A11, and the non-diazotrophic picocyanobacterium Prochlorococcus, varied within the region. At the westernmost stations, numbers were enhanced by organic carbon added as simple sugars, a combination of iron and an organic chelator, or iron added with phosphate. At stations nearest the equator, the nutrient-limiting growth was not apparent. Maximum net growth rates for UCYN-A, C. watsonii and γ-24774A11 were 0.19, 0.61 and 0.52 d(-1), respectively, which are the first known empirical growth rates reported for the uncultivated UCYN-A and the γ-24774A11. The addition of N enhanced total phytoplankton biomass up to 5-fold, and the non-N(2)-fixing Synechococcus was among the groups that responded favorably to N addition. Nitrogen was the major nutrient-limiting phytoplankton biomass in the Western South Pacific Ocean, while availability of organic carbon or iron and organic chelator appear to limit abundances of unicellular diazotrophs. Lack of phytoplankton response to nutrient additions in the Pacific warm pool waters suggests diazotroph growth in this area is controlled by different factors than in the higher latitudes, which may partially explain previously observed variability in community composition in the region.

  14. Isolation and characterization of Arctic microorganisms decomposing bioplastics.

    Science.gov (United States)

    Urbanek, Aneta K; Rymowicz, Waldemar; Strzelecki, Mateusz C; Kociuba, Waldemar; Franczak, Łukasz; Mirończuk, Aleksandra M

    2017-12-01

    The increasing amount of plastic waste causes significant environmental pollution. In this study, screening of Arctic microorganisms which are able to degrade bioplastics was performed. In total, 313 microorganisms were isolated from 52 soil samples from the Arctic region (Spitsbergen). Among the isolated microorganisms, 121 (38.66%) showed biodegradation activity. The ability of clear zone formation on emulsified poly(butylene succinate-co-adipate) (PBSA) was observed for 116 microorganisms (95.87%), on poly(butylene succinate) (PBS) for 73 microorganisms (60.33%), and on poly(ɛ-caprolactone) (PCL) for 102 microorganisms (84.3%). Moreover, the growth of microorganisms on poly(lactic acid) (PLA) agar plates was observed for 56 microorganisms (46.28%). Based on the 16S rRNA sequence, 10 bacterial strains which showed the highest ability for biodegradation were identified as species belonging to Pseudomonas sp. and Rhodococcus sp. The isolated fungal strains were tested for polycaprolactone films and commercial corn and potato starch bags degradation under laboratory conditions. Strains 16G (based on the analysis of a partial 18S rRNA sequence, identified as Clonostachys rosea) and 16H (identified as Trichoderma sp.) showed the highest capability for biodegradation. A particularly high capability for biodegradation was observed for the strain Clonostachys rosea, which showed 100% degradation of starch films and 52.91% degradation of PCL films in a 30-day shake flask experiment. The main advantage of the microorganisms isolated from Arctic environment is the ability to grow at low temperature and efficient biodegradation under this condition. The data suggest that C. rosea can be used in natural and laboratory conditions for degradations of bioplastics.

  15. Fate of indicator microorganisms under nutrient management plan conditions.

    Science.gov (United States)

    Bradford, Scott A; Segal, Eran

    2009-01-01

    Nutrient management plans (NMPs) for application of wastewater from concentrated animal feeding operations are designed to meet crop water and nutrient requirements, but implicitly assume that pathogenic microorganisms in the wastewater will be retained and die-off in the root zone. A NMP was implemented on a field plot to test this assumption by monitoring the fate of several fecal indicator microorganisms (Enterococcus, fecal coliforms, somatic coliphage, and total Escherichia coli). When well-water and wastewater were applied to meet measured evapotranspiration (ET), little advective transport of the indicator microorganisms occurred below the root zone and the remaining microorganisms rapidly died-off (within 1 mo). Additional experiments were conducted in the laboratory to better quantify microorganism transport and survival in the field soil. Batch survival experiments revealed much more rapid die-off rates for the bacterial indicator microorganisms in native than in sterilized soil, suggesting that biotic factors controlled survival. Saturated column experiments with packed field soil, demonstrated much greater transport potential for somatic coliphage than bacterial indicators (Enterococcus and total E. coli) and that the retention rates for the indicator microorganisms were not log-linear with depth. A worst case transport scenario of ponded infiltration on a large undistributed soil column from the field was also initiated and indicator microorganisms were not detected in the column outflow or in the soil at a depth of 65 cm. All of these observations support the hypothesis that a NMP at this site will protect groundwater supplies from microorganism contamination, especially when applied water and wastewater meet ET.

  16. Antimicrobial Compounds from Marine Invertebrates-Derived Microorganisms.

    Science.gov (United States)

    Liu, Juan; Jung, Jee H; Liu, Yonghong

    2016-01-01

    It is known that marine invertebrates, including sponges, tunicates, cnidaria or mollusks, host affluent and various communities of symbiotic microorganisms. The microorganisms associated with the invertebrates metabolized various biologically active compounds, which could be an important resource for the discovery and development of potentially novel drugs. In this review, the new compounds with antimicrobial activity isolated from marine invertebrate-derived microorganisms in the last decade (2004-2014) will be presented, with focus on the relevant antimicrobial activities, origin of isolation, and information of strain species. New compounds without antimicrobial activity were not revealed.

  17. Influence of microorganisms on the alteration of glasses

    International Nuclear Information System (INIS)

    Besnainou, B.; Libert, M.F.

    1997-01-01

    Under specific conditions, microorganisms may enhance the alteration process of basaltic glass. However bacterial activity in the near field of a glass container would be possible only in environmental conditions provide nutrients and energetic substrates for bacterial growth. Depending of these conditions, microorganisms can: - modify the pH or the medium, - consume or produce soluble organic acids. To qualify the long term behaviour of glass, in presence of microorganisms, a qualitative and quantitative estimation of microbial activity potentialities and their consequences is needed. This must be achieved in studying the availability of the chemical species in the environment. (authors)

  18. Regional Ocean Data Assimilation

    KAUST Repository

    Edwards, Christopher A.

    2015-01-03

    This article reviews the past 15 years of developments in regional ocean data assimilation. A variety of scientific, management, and safety-related objectives motivate marine scientists to characterize many ocean environments, including coastal regions. As in weather prediction, the accurate representation of physical, chemical, and/or biological properties in the ocean is challenging. Models and observations alone provide imperfect representations of the ocean state, but together they can offer improved estimates. Variational and sequential methods are among the most widely used in regional ocean systems, and there have been exciting recent advances in ensemble and four-dimensional variational approaches. These techniques are increasingly being tested and adapted for biogeochemical applications.

  19. Computational Ocean Acoustics

    CERN Document Server

    Jensen, Finn B; Porter, Michael B; Schmidt, Henrik

    2011-01-01

    Since the mid-1970s, the computer has played an increasingly pivotal role in the field of ocean acoustics. Faster and less expensive than actual ocean experiments, and capable of accommodating the full complexity of the acoustic problem, numerical models are now standard research tools in ocean laboratories. The progress made in computational ocean acoustics over the last thirty years is summed up in this authoritative and innovatively illustrated new text. Written by some of the field's pioneers, all Fellows of the Acoustical Society of America, Computational Ocean Acoustics presents the latest numerical techniques for solving the wave equation in heterogeneous fluid–solid media. The authors discuss various computational schemes in detail, emphasizing the importance of theoretical foundations that lead directly to numerical implementations for real ocean environments. To further clarify the presentation, the fundamental propagation features of the techniques are illustrated in color. Computational Ocean A...

  20. Antibiotic cytotoxic effects of microorganisms isolated from Jachymov uranium mines

    International Nuclear Information System (INIS)

    Fuska, J.; Fuskova, A.

    1982-01-01

    Microorganisms were isolated from old relinquished uranium mines in Jachymov; they had been growing for several decades in darkness in temperatures of 5 to 12 degC and relative humidity from 80 to 100%. The concentration of uranium salts in mine waters varied from 10 -4 to 10 -5 g.l -1 , that of Rn in the atmosphere was from 0.04 to 40 Bq.l -1 . Of 324 cultures, 18.8% inhibited the growth of Bacillus subtilis, Escherichia coli and Candida pseudotropicalis and 16.6% that of HeLa cells. The frequency of microorganisms inhibiting the growth of HeLa or Ehrlich ascites cells was markedly higher in this set of cultures than among microorganisms kept in culture collections or isolated from other natural habitats. About 10% of the isolated cultures were mycelia sterilia. The following antibiotics were isolated from microorganisms obtained from uranium mines: frequentin, vermiculin, vermicillin, vermistatin, cytostipin and duclauxin. (author)

  1. High throughput screening method for assessing heterogeneity of microorganisms

    NARCIS (Netherlands)

    Ingham, C.J.; Sprenkels, A.J.; van Hylckama Vlieg, J.E.T.; Bomer, Johan G.; de Vos, W.M.; van den Berg, Albert

    2006-01-01

    The invention relates to the field of microbiology. Provided is a method which is particularly powerful for High Throughput Screening (HTS) purposes. More specific a high throughput method for determining heterogeneity or interactions of microorganisms is provided.

  2. SELECTION OF MICROORGANISMS FOR FERMENTATION OF MEAT MATERIALS

    Directory of Open Access Journals (Sweden)

    Danylenko S. G.

    2014-08-01

    Full Text Available Principal criteria for the selection of microorganisms with a wide range of biological and technological properties for fermentation of raw meats are considered. Attention is paid to the main groups of microorganisms such as Micrococсus, Staphylococcus, Lactobacillus, Bifidobacterium and Propionibacterium which are promising for creation of bacterial preparations. To create bacterial preparations, the basic criteria of selection for microorganisms were determined as follows: the ability of microorganisms to be developed within the specific ecological niche (raw meat materials and their influence on flavor characteristics of the final product under the conditions of intensification of production technologies of meat products. Methods used for search and retrieval of technologically promising strains from different natural sources (fresh meats, minced meats, meat, dairy and sour-milk products, vegetables, fruit, brines and mixtures for salting are considered.

  3. Establishing Drug Resistance in Microorganisms by Mass Spectrometry

    Science.gov (United States)

    Demirev, Plamen A.; Hagan, Nathan S.; Antoine, Miquel D.; Lin, Jeffrey S.; Feldman, Andrew B.

    2013-08-01

    A rapid method to determine drug resistance in bacteria based on mass spectrometry is presented. In it, a mass spectrum of an intact microorganism grown in drug-containing stable isotope-labeled media is compared with a mass spectrum of the intact microorganism grown in non-labeled media without the drug present. Drug resistance is determined by predicting characteristic mass shifts of one or more microorganism biomarkers using bioinformatics algorithms. Observing such characteristic mass shifts indicates that the microorganism is viable even in the presence of the drug, thus incorporating the isotopic label into characteristic biomarker molecules. The performance of the method is illustrated on the example of intact E. coli, grown in control (unlabeled) and 13C-labeled media, and analyzed by MALDI TOF MS. Algorithms for data analysis are presented as well.

  4. Effect of Microorganisms in the Bioremediation of Spent Engine Oil ...

    African Journals Online (AJOL)

    ADOWIE PERE

    interaction of these factors as suitable conditions are provided (Rahman et al., ... Magnesium, Copper, Zinc, Lead, Cadmium and so on from the wear and tear of the ..... microorganisms would also require essential nutrients as hydrocarbons ...

  5. Anisotropic structures of some microorganisms studied by polarization microscopy

    Czech Academy of Sciences Publication Activity Database

    Žižka, Zdeněk

    2014-01-01

    Roč. 59, č. 5 (2014), s. 363-368 ISSN 0015-5632 Institutional support: RVO:61388971 Keywords : Polarization microscopy * microorganism Subject RIV: EE - Microbiology, Virology Impact factor: 1.000, year: 2014

  6. Diversity and adaptations of deep-sea microorganisms

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.

    -tolerant enzymes, natural products of potential use in human health management and environmental bioremediation using solvent-tolerant microorganisms are some of the potential biotechnological applications of these deep-sea microbes....

  7. A device for continuous microscopic examination of aquatic microorganisms

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, S.

    The device consists of a sealed microscopic mount provided with an inlet for liquid medium and an outlet, permitting continuous flow of the liquid. It permits observation of development of marine microorganisms such as thraustochytrids for 3 d...

  8. isolation and identification of the microorganisms most prevalent

    African Journals Online (AJOL)

    problems presenting in eye clinics on a daily basis. With one or two ... microorganisms most prevalent in external eye infections in Owerri urban (as seen Mercy Eye clinic). With the aid of sterile .... through personal contacts. Consequently, the.

  9. Multiorganismal insects: diversity and function of resident microorganisms.

    Science.gov (United States)

    Douglas, Angela E

    2015-01-07

    All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contributing to nutrition, especially by providing essential amino acids, B vitamins, and, for fungal partners, sterols. Some microorganisms protect their insect hosts against pathogens, parasitoids, and other parasites by synthesizing specific toxins or modifying the insect immune system. Priorities for future research include elucidation of microbial contributions to detoxification, especially of plant allelochemicals in phytophagous insects, and resistance to pathogens; as well as their role in among-insect communication; and the potential value of manipulation of the microbiota to control insect pests.

  10. Isolation and screening of microorganisms from a gari fermentation ...

    African Journals Online (AJOL)

    Isolation and screening of microorganisms from a gari fermentation process for starter culture development. Vinodh A Edward, Moutairou Egounlety, Melanie Huch, Petrus J Van Zyl, Suren Singh, Naledzani D Nesengani, Vetja M Haakuria, Charles MAP Franz ...

  11. Fluid flow enhances the effectiveness of toxin export by aquatic microorganisms: a first-passage perspective

    Science.gov (United States)

    Licata, Nicholas; Clark, Aaron

    2014-03-01

    Aquatic microorganisms face a variety of challenges in the course of development. One central challenge is efficiently regulating the export of toxic molecules inside the developing embryo. The strategies employed should be robust with respect to the variable ocean environment and limit the chances that exported toxins are reabsorbed. In this talk we consider the first-passage problem for the uptake of exported toxins by a spherical embryo. A perturbative solution of the advection-diffusion equation reveals that a concentration boundary layer forms in the vicinity of the embryo, and that fluid flow enhances the effectiveness of toxin export. We highlight connections between the model results and recent experiments on the development of sea urchin embryos. We acknowledge financial support from the University of Michigan-Dearobrn CASL Faculty Summer Research Grant.

  12. Isolation of microorganisms for biological control the moniliophthora roreri

    OpenAIRE

    suarez contreras, liliana yanet; Rangel Riaño, Alba Luz

    2014-01-01

    Moniliophlhora roreri is the causal agent of cocoa Moniliasis, which produces losses of up to 60% of the crop, as it affects only its commercial product, the cob. Biological control appears as an alternative management, using endophytic microorganisms. The reason because of this research came up was that it was aimed to isolate microorganisms with antagonist potential for biological control towards the phytopathogen M. roreri in Norte de Santander. This is done through isolation and identifica...

  13. Microorganisms having enhanced tolerance to inhibitors and stress

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Steven D.; Yang, Shihui

    2014-07-29

    The present invention provides genetically modified strains of microorganisms that display enhanced tolerance to stress and/or inhibitors such as sodium acetate and vanillin. The enhanced tolerance can be achieved by increasing the expression of a protein of the Sm-like superfamily such as a bacterial Hfq protein and a fungal Sm or Lsm protein. Further, the present invention provides methods of producing alcohol from biomass materials by using the genetically modified microorganisms of the present invention.

  14. Microorganisms -indicators of the level of soil pollution with lead

    OpenAIRE

    Stavreva Veselinovska, Snezana

    2011-01-01

    Environmental pollution with heavy metals present a real threat to wildlife because the metals cannot be naturally decomposed as is the case with organic pollutants, and as such they can survive in the environment while accumulating the heavy metals in different parts. Pollution with metals can affect different organisms in the environment, such as microorganisms, plants and animals, but the degree of toxicity depends on the species. Microorganisms have different mechanisms of coping with...

  15. The microorganisms as a renewable source of ecological clean fuel

    International Nuclear Information System (INIS)

    Shalygo, N.V.; Mel'nikov, S.S.; Manankina, E.E.; Budakova, E.A.; Kolyago, V.M.

    2006-01-01

    Five families of microorganisms (Bacillaceae, Rhodospirillaceae, Cyanophyceae, Chlorophyceae and Euglenophyceae) as hydrogen producers were tested and the conditions that are necessary for hydrogen photoproduction were investigated. It was shown, that the most effective producers of hydrogen were Rhodobacter spheroides, Clostridium sp.; Euglena gracilis var. bacillaris and Chlamydomonas reinhardtii. Addition of glucose, iron and vanadium salts resulted in the increase of hydrogen production. Polycultures consisted of two or three microorganisms were more effective hydrogen producers compared to separate monocultures. (authors)

  16. Method for treating wastewater using microorganisms and vascular aquatic plants

    Science.gov (United States)

    Wolverton, B. C. (Inventor)

    1983-01-01

    A method for treating wastewater compresses subjecting the wastewater to an anaerobic setting step for at least 6 hours and passing the liquid effluent from the anaerobic settling step through a filter cell in an upflow manner. There the effluent is subjected first to the action of anaerobic and facultative microorganisms, and then to the action of aerobic microorganisms and the roots of at least one vascular aquatic plant.

  17. Swimming of Microorganisms Viewed from String and Membrane Theories

    OpenAIRE

    Kawamura, Masako; Sugamoto, Akio; Nojiri, Shin'ichi

    1993-01-01

    Swimming of microorganisms is studied from a viewpoint of extended objects (strings and membranes) swimming in the incompressible f luid of low Reynolds number. The flagellated motion is analyzed in two dimensional fluid, by using the method developed in the ciliated motion with the Joukowski transformation. Discussion is given on the conserved charges and the algebra which are associated with the area (volume)- preserving diffeomorphisms giving the swimming motion of microorganisms. It is al...

  18. Evolution, Metabolism and Biotechnological Usage of Methylotrophic Microorganisms

    OpenAIRE

    Oleg Mosin; Ignat Ignatov

    2014-01-01

    Methylotrophs – aerobic chemoheterotrophic microorganisms submitted by cocci and bacilli mobile forms, are inhabitants of reservoirs and soils of various type, where there are going on various processes of decomposition of organic substances with formation of the one-carbon С1-compounds and some С2-, and С3-compounds, capable to be assimilated by methylotrophs. These microorganisms assimilating carbon on ribuloso-5-monophospate and serine pathways, are allocated from soil ground, the sewage c...

  19. Characteristics of Microorganism's Fouling on Lithium Adsorbents in Okgye Harbor, Gangneung, Korea

    Science.gov (United States)

    Kim, J.; Yoon, H.; Kong, M.; Yoon, B.; Ryu, J.; Chung, K.; Kim, B.

    2013-12-01

    Marine microorganisms bring about serious ramification for nautical industry such as marine construction. Interaction of bacteria and phytoplankton causes biofouling to marine environments. To understand the marine microorganism's reaction on the inorganic surface, the experimental work carried out in pilot plant for lithium recovery field at Okgye Harbor, Gangneung, Korea through seasonal interval. To inquiry into the surface's effect for lithium recovery adsorbents by bacterial communities and phytoplankton, disk type inorganic adsorbents were immersed in same site at depth of 5 m for 7 days, 14 days and 21 days. Culturable marine bacteria were isolated and identified by 16S rRNA sequencing. Also, size and shape of marine organisms and the adsorption circumstance were investigated by SEM and CLSM (confocal laser scanning microscope). At longer exposure time of adsorbents, increase the bacterial number of individual. Vibrio sp., represented dominant species of biofouling after 21 days and marine phytoplankton increased 7 times after 7 days. Size of phytoplankton were about 50 ~ 100 μm in 0.25 mm2 area of lithium adsorbents. To increase lithium recovery rate of lithium adsorbents and to minimize the biofouling effects, it is necessary to conduct consistently field monitoring. Acknowledgments This research was supported by the national research project titled 'The Development of Technology for Extraction of Resources Dissolved in Seawater' of the Korea Institute of Geoscience and Mineral Resources (KIGAM) funded by the Ministry of Ocean and Fisheries.

  20. Volatilization of Po by microorganisms at laboratory culture experiments

    International Nuclear Information System (INIS)

    Momoshima, N.; Ishida, A.; Yoshinaga, C.; Fukuda, A.

    2005-01-01

    The previous experiments proved the volatility of polonium form culture medium in which microorganisms were propagated from seed of seawater, river water or pond water, therefore we did not know what kind of species are responsible to Po volatility. To search microorganisms, which concerned with Po emission we carried out culture experiments using known microorganisms. Three microorganisms were examined; Escherichia coli K-12, Bacillus subtilis and Chromobacterium violaceum. The microorganisms were pre-cultured in LB medium at 30 degree C and a small portion of the pre-cultured was transferred to a culture bottle in which LB medium and 208 Po tracer were contained. The culture was done at 30 degree C with shaking the culture bottle and air passed through a filter was introduced. The Po volatilized was transferred into the trap vials in which scintillator for liquid scintillation counting (LSC) was contained. The Po activity was measured by LSC. All of the microorganisms examined volatilized Po but their ability was quite different each other. Highest ability was observed on Chromobacterium violaceum and then Escherichia coli K-12 followed by Bacillus subtilis, the relative magnitude of the ability was 10 2 , 10, 1, respectively. Chromobacterium violaceum and Escherichia coli K-12 showed high volatility for the first 24 h but Escherichia coli K-12 showed a decrease thereafter. However high volatility was continued on Chromobacterium violaceum during the culture. The low culture temperature suppressed Po volatility, supporting biologically mediated Po emission from the culture.

  1. Synergistic interface behavior of strontium adsorption using mixed microorganisms.

    Science.gov (United States)

    Hu, Wenyuan; Dong, Faqin; Yang, Guangmin; Peng, Xin; Huang, Xiaojun; Liu, Mingxue; Zhang, Jing

    2017-08-10

    The proper handling of low-level radioactive waste is crucial to promote the sustainable development of nuclear power. Research into the mechanism for interactions between bacterium and radionuclides is the starting point for achieving successful remediation of radionuclides with microorganisms. Using Sr(II) as a simulation radionuclide and the mixed microorganisms of Saccharomyces cerevisiae and Bacillus subtilis as the biological adsorbent, this study investigates behavior at the interface between Sr(II) and the microorganisms as well as the mechanisms governing that behavior. The results show that the optimal ratio of mixed microorganisms is S. cerevisiae 2.0 g L -1 to B. subtilis 0.05 g L -1 , and the optimal pH is about 6.3. Sr(II) biosorption onto the mixed microorganisms is spontaneous and endothermic in nature. The kinetics and the equilibrium isotherm data of the biosorption process can be described with pseudo-second-order equation and the Langmuir isotherm equation, respectively. The key interaction between the biological adsorbent and Sr(II) involves shared electronic pairs arising from chemical reactions via bond complexation or electronic exchange, and spectral and energy spectrum analysis show that functional groups (e.g., hydroxyl, carboxyl, amino, amide) at the interface between the radionuclide and the mixed microorganisms are the main active sites of the interface reactions.

  2. Major role of nitrite-oxidizing bacteria in dark ocean carbon fixation

    NARCIS (Netherlands)

    Pachiadaki, M.G.; Sintes, E.; Bergauer, K.; Brown, J.M.; Record, N.R.; Swan, B.K.; Mathyer, M.E.; Hallam, S.J.; López-Garcìa, P.; Takaki, Y.; Nunoura, T.; Woyke, T.; Herndl, G.J.; Stepanauskas, R.

    2017-01-01

    Carbon fixation by chemoautotrophic microorganisms in the dark ocean has a major impact on global carbon cycling and ecological relationships in the ocean’s interior, but the relevant taxa and energy sources remain enigmatic.We show evidence that nitrite-oxidizing bacteria affiliated with the

  3. The Southern Ocean Observing System

    OpenAIRE

    Rintoul, Stephen R.; Meredith, Michael P.; Schofield, Oscar; Newman, Louise

    2012-01-01

    The Southern Ocean includes the only latitude band where the ocean circles the earth unobstructed by continental boundaries. This accident of geography has profound consequences for global ocean circulation, biogeochemical cycles, and climate. The Southern Ocean connects the ocean basins and links the shallow and deep limbs of the overturning circulation (Rintoul et al., 2001). The ocean's capacity to moderate the pace of climate change is therefore influenced strongly by the Southern Ocean's...

  4. Deciphering ocean carbon in a changing world.

    Science.gov (United States)

    Moran, Mary Ann; Kujawinski, Elizabeth B; Stubbins, Aron; Fatland, Rob; Aluwihare, Lihini I; Buchan, Alison; Crump, Byron C; Dorrestein, Pieter C; Dyhrman, Sonya T; Hess, Nancy J; Howe, Bill; Longnecker, Krista; Medeiros, Patricia M; Niggemann, Jutta; Obernosterer, Ingrid; Repeta, Daniel J; Waldbauer, Jacob R

    2016-03-22

    Dissolved organic matter (DOM) in the oceans is one of the largest pools of reduced carbon on Earth, comparable in size to the atmospheric CO2 reservoir. A vast number of compounds are present in DOM, and they play important roles in all major element cycles, contribute to the storage of atmospheric CO2 in the ocean, support marine ecosystems, and facilitate interactions between organisms. At the heart of the DOM cycle lie molecular-level relationships between the individual compounds in DOM and the members of the ocean microbiome that produce and consume them. In the past, these connections have eluded clear definition because of the sheer numerical complexity of both DOM molecules and microorganisms. Emerging tools in analytical chemistry, microbiology, and informatics are breaking down the barriers to a fuller appreciation of these connections. Here we highlight questions being addressed using recent methodological and technological developments in those fields and consider how these advances are transforming our understanding of some of the most important reactions of the marine carbon cycle.

  5. Ejecta from Ocean Impacts

    Science.gov (United States)

    Kyte, Frank T.

    2003-01-01

    Numerical simulations of deep-ocean impact provide some limits on the size of a projectile that will not mix with the ocean floor during a deep-ocean impact. For a vertical impact at asteroidal velocities (approx. 20 km/s), mixing is only likely when the projectile diameter is greater than 112 of the water depth. For oblique impacts, even larger projectiles will not mix with ocean floor silicates. Given the typical water depths of 4 to 5 km in deep-ocean basins, asteroidal projectiles with diameters as large as 2 or 3 km may commonly produce silicate ejecta that is composed only of meteoritic materials and seawater salts. However, the compressed water column beneath the projectile can still disrupt and shock metamorphose the ocean floor. Therefore, production of a separate, terrestrial ejecta component is not ruled out in the most extreme case. With increasing projectile size (or energy) relative to water depths, there must be a gradation between oceanic impacts and more conventional continental impacts. Given that 60% of the Earth's surface is covered by oceanic lithosphere and 500 m projectiles impact the Earth on 10(exp 5) y timescales, there must be hundreds of oceanic impact deposits in the sediment record awaiting discovery.

  6. Compost supplementation with nutrients and microorganisms in composting process.

    Science.gov (United States)

    Sánchez, Óscar J; Ospina, Diego A; Montoya, Sandra

    2017-11-01

    The composting is an aerobic, microorganism-mediated, solid-state fermentation process by which different organic materials are transformed into more stable compounds. The product obtained is the compost, which contributes to the improvement of physical, chemical and microbiological properties of the soil. However, the compost usage in agriculture is constrained because of its long-time action and reduced supply of nutrients to the crops. To enhance the content of nutrients assimilable by the plants in the compost, its supplementation with nutrients and inoculation with microorganisms have been proposed. The objective of this work was to review the state of the art on compost supplementation with nutrients and the role played by the microorganisms involved (or added) in their transformation during the composting process. The phases of composting are briefly compiled and different strategies for supplementation are analyzed. The utilization of nitrogenous materials and addition of microorganisms fixing nitrogen from the atmosphere or oxidizing ammonia into more assimilable for plants nitrogenous forms are analyzed. Several strategies for nitrogen conservation during composting are presented as well. The supplementation with phosphorus and utilization of microorganisms solubilizing phosphorus and potassium are also discussed. Main groups of microorganisms relevant during the composting process are described as well as most important strategies to identify them. In general, the development of this type of nutrient-enriched bio-inputs requires research and development not only in the supplementation of compost itself, but also in the isolation and identification of microorganisms and genes allowing the degradation and conversion of nitrogenous substances and materials containing potassium and phosphorus present in the feedstocks undergoing the composting process. In this sense, most important research trends and strategies to increase nutrient content in the compost

  7. Our Changing Oceans: All about Ocean Acidification

    International Nuclear Information System (INIS)

    Rickwood, Peter

    2013-01-01

    The consequences of ocean acidification are global in scale. More research into ocean acidification and its consequences is needed. It is already known, for example, that there are regional differences in the vulnerability of fisheries to acidification. The combination of other factors, such as global warming, the destruction of habitats, overfishing and pollution, need to be taken into account when developing strategies to increase the marine environment’s resilience. Among steps that can be taken to reduce the impact is better protection of marine coastal ecosystems, such as mangrove swamps and seagrass meadows, which will help protect fisheries. This recommendation was one of the conclusions of a three-day workshop attended by economists and scientists and organized by the IAEA and the Centre Scientifique de Monaco in November 2012. In their recommendations the workshop also stressed that the impact of increasing ocean acidity must be taken into account in the management of fisheries, particularly where seafood is a main dietary source

  8. Blue ocean strategy.

    Science.gov (United States)

    Kim, W Chan; Mauborgne, Renée

    2004-10-01

    Despite a long-term decline in the circus industry, Cirque du Soleil profitably increased revenue 22-fold over the last ten years by reinventing the circus. Rather than competing within the confines of the existing industry or trying to steal customers from rivals, Cirque developed uncontested market space that made the competition irrelevant. Cirque created what the authors call a blue ocean, a previously unknown market space. In blue oceans, demand is created rather than fought over. There is ample opportunity for growth that is both profitable and rapid. In red oceans--that is, in all the industries already existing--companies compete by grabbing for a greater share of limited demand. As the market space gets more crowded, prospects for profits and growth decline. Products turn into commodities, and increasing competition turns the water bloody. There are two ways to create blue oceans. One is to launch completely new industries, as eBay did with online auctions. But it's much more common for a blue ocean to be created from within a red ocean when a company expands the boundaries of an existing industry. In studying more than 150 blue ocean creations in over 30 industries, the authors observed that the traditional units of strategic analysis--company and industry--are of limited use in explaining how and why blue oceans are created. The most appropriate unit of analysis is the strategic move, the set of managerial actions and decisions involved in making a major market-creating business offering. Creating blue oceans builds brands. So powerful is blue ocean strategy, in fact, that a blue ocean strategic move can create brand equity that lasts for decades.

  9. [Relationships between air conditioning, airborne microorganisms and health].

    Science.gov (United States)

    Parat, S; Perdrix, A; Baconnier, P

    1999-01-01

    Concurrently with the increase of air-conditioning, potentially severe or frequent new diseases have emerged, giving rise to social and economical consequences. The first part of this work is a state of the art review of the relationships between air-conditioning, airborne microorganisms and health, through a technical, metrological and medical approach. The second part presents four studies performed in this field. Two of them deal with the relationship between airborne microorganisms and technical features of air-conditioning. Measurements performed on actual sites demonstrated the benefit of using high efficiency filters and low risk components in air-conditioning systems. The third study was aimed to look for a relationship between airborne microorganisms and sick building syndrome symptoms. Statistical analyses of individual data revealed significant associations between airborne bacteria or fungi and symptoms. These results may be the first step in determining a dose-response relationship, in order to define threshold limit values in this field. In the fourth study, the contribution of particle counting in assessing exposure to airborne microorganisms was explored by monitoring simultaneous variations of microbial and particle concentrations. The results showed that associating particle counting may allow to detect microbial variations instantaneously, and therefore improve the assessment of exposure to airborne microorganisms.

  10. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia.

    Science.gov (United States)

    Avellaneda-Torres, Lizeth Manuela; Pulido, Claudia Patricia Guevara; Rojas, Esperanza Torres

    2014-01-01

    A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP), Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS) of ribosomal DNA for fungi. Multivariate statistical analysis (MVA) was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

  11. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia

    Directory of Open Access Journals (Sweden)

    Lizeth Manuela Avellaneda-Torres

    2014-12-01

    Full Text Available A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP, Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS of ribosomal DNA for fungi. Multivariate statistical analysis (MVA was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

  12. Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications.

    Science.gov (United States)

    Gudiña, Eduardo J; Teixeira, José A; Rodrigues, Lígia R

    2016-02-18

    Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens), and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies. However, marine biosurfactants have not been widely explored, mainly due to the difficulties associated with the isolation and growth of their producing microorganisms. Culture-independent techniques (metagenomics) constitute a promising approach to study the genetic resources of otherwise inaccessible marine microorganisms without the requirement of culturing them, and can contribute to the discovery of novel biosurfactants with significant biological activities. This paper reviews the most relevant biosurfactants produced by marine microorganisms with potential therapeutic applications and discusses future perspectives and opportunities to discover novel molecules from marine environments.

  13. Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Eduardo J. Gudiña

    2016-02-01

    Full Text Available Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens, and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies. However, marine biosurfactants have not been widely explored, mainly due to the difficulties associated with the isolation and growth of their producing microorganisms. Culture-independent techniques (metagenomics constitute a promising approach to study the genetic resources of otherwise inaccessible marine microorganisms without the requirement of culturing them, and can contribute to the discovery of novel biosurfactants with significant biological activities. This paper reviews the most relevant biosurfactants produced by marine microorganisms with potential therapeutic applications and discusses future perspectives and opportunities to discover novel molecules from marine environments.

  14. Role of Microorganisms in the Removal of Radionuclides from Soil

    International Nuclear Information System (INIS)

    Bashandy, A.S.

    2007-01-01

    Resistance to radio nuclides and their accumulation by bacteria is a wide spread phenomenon that can be explored for the improvement of the environment. Metal resistant bacteria have developed very efficient and varying mechanisms for tolerating high levels of. toxic metals and thus hold potential for controlling heavy metal pollution. This property has been successfully applied for metal removal from soil. A total of 59 microorganisms were isolated from 5 locations in Sinai Desert. The microorganisms were examined for resistance to strontium, cobalt and cesium by spot technique on two kinds of media containing metals, Nutrient agar and King B agar. The resistant microorganisms were identified morphologically by Gram stain. The microorganisms were resistant to Sr and Cs at concentrations up to 200 mg/I and while Co proved to be toxic at a concentration of 100 mg/ I. The mechanisms of metal resistance to high concentrations were studied. Evidence show that the isolated microorganisms can uptake high concentrations of the studied elements. The results also, indicated that no binding proteins are released in the environment of the studied isolate

  15. Cybernetic modeling of adaptive prediction of environmental changes by microorganisms.

    Science.gov (United States)

    Mandli, Aravinda R; Modak, Jayant M

    2014-02-01

    Microorganisms exhibit varied regulatory strategies such as direct regulation, symmetric anticipatory regulation, asymmetric anticipatory regulation, etc. Current mathematical modeling frameworks for the growth of microorganisms either do not incorporate regulation or assume that the microorganisms utilize the direct regulation strategy. In the present study, we extend the cybernetic modeling framework to account for asymmetric anticipatory regulation strategy. The extended model accurately captures various experimental observations. We use the developed model to explore the fitness advantage provided by the asymmetric anticipatory regulation strategy and observe that the optimal extent of asymmetric regulation depends on the selective pressure that the microorganisms experience. We also explore the importance of timing the response in anticipatory regulation and find that there is an optimal time, dependent on the extent of asymmetric regulation, at which microorganisms should respond anticipatorily to maximize their fitness. We then discuss the advantages offered by the cybernetic modeling framework over other modeling frameworks in modeling the asymmetric anticipatory regulation strategy. Copyright © 2013. Published by Elsevier Inc.

  16. Mini-review: Inhibition of biofouling by marine microorganisms.

    Science.gov (United States)

    Dobretsov, Sergey; Abed, Raeid M M; Teplitski, Max

    2013-01-01

    Any natural or artificial substratum exposed to seawater is quickly fouled by marine microorganisms and later by macrofouling species. Microfouling organisms on the surface of a substratum form heterogenic biofilms, which are composed of multiple species of heterotrophic bacteria, cyanobacteria, diatoms, protozoa and fungi. Biofilms on artificial structures create serious problems for industries worldwide, with effects including an increase in drag force and metal corrosion as well as a reduction in heat transfer efficiency. Additionally, microorganisms produce chemical compounds that may induce or inhibit settlement and growth of other fouling organisms. Since the last review by the first author on inhibition of biofouling by marine microbes in 2006, significant progress has been made in the field. Several antimicrobial, antialgal and antilarval compounds have been isolated from heterotrophic marine bacteria, cyanobacteria and fungi. Some of these compounds have multiple bioactivities. Microorganisms are able to disrupt biofilms by inhibition of bacterial signalling and production of enzymes that degrade bacterial signals and polymers. Epibiotic microorganisms associated with marine algae and invertebrates have a high antifouling (AF) potential, which can be used to solve biofouling problems in industry. However, more information about the production of AF compounds by marine microorganisms in situ and their mechanisms of action needs to be obtained. This review focuses on the AF activity of marine heterotrophic bacteria, cyanobacteria and fungi and covers publications from 2006 up to the end of 2012.

  17. Blue Ocean Thinking

    Science.gov (United States)

    Orem, Donna

    2016-01-01

    This article describes a concept called the "blue ocean thinking strategy," developed by W. Chan Kim and Renée Mauborgne, professors at INSEAD, an international graduate school of business in France. The "blue ocean" thinking strategy considers opportunities to create new markets for services, rather than focusing solely on…

  18. Indian Ocean Rim Cooperation

    DEFF Research Database (Denmark)

    Wippel, Steffen

    Since the mid-1990s, the Indian Ocean has been experiencing increasing economic cooperation among its rim states. Middle Eastern countries, too, participate in the work of the Indian Ocean Rim Association, which received new impetus in the course of the current decade. Notably Oman is a very active...

  19. Communicating Ocean Acidification

    Science.gov (United States)

    Pope, Aaron; Selna, Elizabeth

    2013-01-01

    Participation in a study circle through the National Network of Ocean and Climate Change Interpretation (NNOCCI) project enabled staff at the California Academy of Sciences to effectively engage visitors on climate change and ocean acidification topics. Strategic framing tactics were used as staff revised the scripted Coral Reef Dive program,…

  20. Global Ocean Phytoplankton

    Science.gov (United States)

    Franz, B. A.; Behrenfeld, M. J.; Siegel, D. A.; Werdell, P. J.

    2014-01-01

    Marine phytoplankton are responsible for roughly half the net primary production (NPP) on Earth, fixing atmospheric CO2 into food that fuels global ocean ecosystems and drives the ocean's biogeochemical cycles. Phytoplankton growth is highly sensitive to variations in ocean physical properties, such as upper ocean stratification and light availability within this mixed layer. Satellite ocean color sensors, such as the Sea-viewing Wide Field-of-view Sensor (SeaWiFS; McClain 2009) and Moderate Resolution Imaging Spectroradiometer (MODIS; Esaias 1998), provide observations of sufficient frequency and geographic coverage to globally monitor physically-driven changes in phytoplankton distributions. In practice, ocean color sensors retrieve the spectral distribution of visible solar radiation reflected upward from beneath the ocean surface, which can then be related to changes in the photosynthetic phytoplankton pigment, chlorophyll- a (Chla; measured in mg m-3). Here, global Chla data for 2013 are evaluated within the context of the 16-year continuous record provided through the combined observations of SeaWiFS (1997-2010) and MODIS on Aqua (MODISA; 2002-present). Ocean color measurements from the recently launched Visible and Infrared Imaging Radiometer Suite (VIIRS; 2011-present) are also considered, but results suggest that the temporal calibration of the VIIRS sensor is not yet sufficiently stable for quantitative global change studies. All MODISA (version 2013.1), SeaWiFS (version 2010.0), and VIIRS (version 2013.1) data presented here were produced by NASA using consistent Chla algorithms.

  1. Microbial alignment in flow changes ocean light climate.

    Science.gov (United States)

    Marcos; Seymour, Justin R; Luhar, Mitul; Durham, William M; Mitchell, James G; Macke, Andreas; Stocker, Roman

    2011-03-08

    The growth of microbial cultures in the laboratory often is assessed informally with a quick flick of the wrist: dense suspensions of microorganisms produce translucent "swirls" when agitated. Here, we rationalize the mechanism behind this phenomenon and show that the same process may affect the propagation of light through the upper ocean. Analogous to the shaken test tubes, the ocean can be characterized by intense fluid motion and abundant microorganisms. We demonstrate that the swirl patterns arise when elongated microorganisms align preferentially in the direction of fluid flow and alter light scattering. Using a combination of experiments and mathematical modeling, we find that this phenomenon can be recurrent under typical marine conditions. Moderate shear rates (0.1 s(-1)) can increase optical backscattering of natural microbial assemblages by more than 20%, and even small shear rates (0.001 s(-1)) can increase backscattering from blooms of large phytoplankton by more than 30%. These results imply that fluid flow, currently neglected in models of marine optics, may exert an important control on light propagation, influencing rates of global carbon fixation and how we estimate these rates via remote sensing.

  2. Ocean acidification postcards

    Science.gov (United States)

    Schreppel, Heather A.; Cimitile, Matthew J.

    2011-01-01

    The U.S. Geological Survey (USGS) is conducting research on ocean acidification in polar, temperate, subtropical, and tropical regions including the Arctic, West Florida Shelf, and the Caribbean. Project activities include field assessment, experimental laboratory studies, and evaluation of existing data. The USGS is participating in international and interagency working groups to develop research strategies to increase understanding of the global implications of ocean acidification. Research strategies include new approaches for seawater chemistry observation and modeling, assessment of physiological effects on organisms, changes in marine ecosystem structure, new technologies, and information resources. These postcards highlight ongoing USGS research efforts in ocean acidification and carbon cycling in marine and coastal ecosystems in three different regions: polar, temperate, and tropical. To learn more about ocean acidification visit: http://coastal.er.usgs.gov/ocean-acidification/.

  3. Microbial genome-enabled insights into plant-microorganism interactions.

    Science.gov (United States)

    Guttman, David S; McHardy, Alice C; Schulze-Lefert, Paul

    2014-12-01

    Advances in genome-based studies on plant-associated microorganisms have transformed our understanding of many plant pathogens and are beginning to greatly widen our knowledge of plant interactions with mutualistic and commensal microorganisms. Pathogenomics has revealed how pathogenic microorganisms adapt to particular hosts, subvert innate immune responses and change host range, as well as how new pathogen species emerge. Similarly, culture-independent community profiling methods, coupled with metagenomic and metatranscriptomic studies, have provided the first insights into the emerging field of research on plant-associated microbial communities. Together, these approaches have the potential to bridge the gap between plant microbial ecology and plant pathology, which have traditionally been two distinct research fields.

  4. Organotins and microorganisms. Yuki suzu kagobutsu to biseibutsu

    Energy Technology Data Exchange (ETDEWEB)

    Shinoda, S.; Onogi, H. (Okayama Univ., Okayama (Japan). Faculty of Pharmaceutical Sciences)

    1992-08-10

    Tributyltin (TBT) and triphenyltin have higher toxicity than other organotin compounds and are used as biocides, but in recent years the pollution of water and aquatic organisms has become a social problem. This paper describes the interaction between organotin compounds and microorganisms, centering on the decomposition of TBT. Part of microalgae whose activity is promoted by light or nutritive salts within an aquatic environment play an important role in TBT decomposition. Diatoms, and dinoflagellataes are mentioned as the examples. Moreover, an example in which microorganisms promote the transformation of inorganotin compounds to dimethyltin or trimethyltin is given. However, it is pointed out in this paper that the action of microorganisms relates greatly to the continuance of existence of organotins in environments, but the degradation efficiency is considered to be very low and prevention against pollution is of primary importance. 32 refs., 2 figs., 3 tabs.

  5. Microscale interactions between earthworms and microorganisms: a review

    Directory of Open Access Journals (Sweden)

    Zirbes, L.

    2012-01-01

    Full Text Available Microorganisms are well adapted to their soil microhabitat where they live together in consortia, interacting with other living members, including earthworms. This literature review consists of four sections that focus on microscale interactions between earthworms and microorganisms. The first part is devoted to nephridia symbiosis. Recent discoveries show that Verminephrobacter spp. is present as a symbiont in earthworm nephridia. The second section deals with earthworm food preference and focuses on the major hypotheses of foraging strategies. The third section presents evidence of gut symbionts and highlights the need for additional studies in this field. The last section of this review explains why microorganism activities are enhanced in burrows and casts of earthworms.

  6. Use of Probiotic Microorganisms for Bio-Protective Aims

    Directory of Open Access Journals (Sweden)

    Filiz YANGILAR

    2015-03-01

    Full Text Available It was known that some diseases can be treated as the result of the use of antibiotics in certain periods and at certain dosages while inactivating and deteriorating normal microorganisms performing useful activities in human metabolism (in especially intestinal flora. It was occured that after the use of antibiotics, some defects can be seen resulting from antibiotics (such as allergy, diarrhea, gas formation etc. With this aim, nutraceutics and functional food have gained importance over the last years and consumers began to be interested in probiotics, natural antioxidants, dietary fibres, products with low calorie and cholesterol contents, especially the products containing probioticbacteria. Bacteriocins produced by probiotic bacteria can play important roles as food protective and safeguarding since they can compete with unwanted or pathogen microorganisms survive in the media and colonize in intestines. In this review, is aimed to emphasis bioprotective compounds, advantages and disadvantages of biopreservation method and the importance of the mechanisms of probiotic microorganisms.

  7. Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms

    International Nuclear Information System (INIS)

    Gonzalez-Barreiro, O.; Rioboo, C.; Herrero, C.; Cid, A.

    2006-01-01

    The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides

  8. Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Barreiro, O. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Rioboo, C. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Herrero, C. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Cid, A. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain)]. E-mail: cid@udc.es

    2006-11-15

    The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides.

  9. Massive salp swarm tilts ocean's chemical balance

    Science.gov (United States)

    Schultz, Colin

    2012-03-01

    A surge of nutrients to the warm waters off the southeastern coast of Australia during the highly productive austral spring can spark an explosion in the phytoplankton population. Where phytoplankton bloom, so do the predators that feed on them. Some, like the globally prevalent salp Thalia democratica, excel at capitalizing on the transient nature of phytoplankton blooms. Salps are tiny gelatinous creatures that feed on plankton and other microorganisms by straining them from the ocean water with a fine mesh sieve. A rarity among multicellular animals, salps retain the ability to reproduce by asexual budding, with one salp spawning a clone of itself. This budding, combined with sexual reproduction, enables salp populations to grow by up to 250% per day.

  10. Identification of beer spoilage microorganisms using the MALDI Biotyper platform.

    Science.gov (United States)

    Turvey, Michelle Elizabeth; Weiland, Florian; Meneses, Jon; Sterenberg, Nick; Hoffmann, Peter

    2016-03-01

    Beer spoilage microorganisms present a major risk for the brewing industry and can lead to cost-intensive recall of contaminated products and damage to brand reputation. The applicability of molecular profiling using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) in combination with Biotyper software was investigated for the identification of beer spoilage microorganisms from routine brewery quality control samples. Reference mass spectrum profiles for three of the most common bacterial beer spoilage microorganisms (Lactobacillus lindneri, Lactobacillus brevis and Pediococcus damnosus), four commercially available brewing yeast strains (top- and bottom-fermenting) and Dekkera/Brettanomyces bruxellensis wild yeast were established, incorporated into the Biotyper reference library and validated by successful identification after inoculation into beer. Each bacterial species could be accurately identified and distinguished from one another and from over 5600 other microorganisms present in the Biotyper database. In addition, wild yeast contaminations were rapidly detected and distinguished from top- and bottom-fermenting brewing strains. The applicability and integration of mass spectrometry profiling using the Biotyper platform into existing brewery quality assurance practices within industry were assessed by analysing routine microbiology control samples from a local brewery, where contaminating microorganisms could be reliably identified. Brewery-isolated microorganisms not present in the Biotyper database were further analysed for identification using LC-MS/MS methods. This renders the Biotyper platform a promising candidate for biological quality control testing within the brewing industry as a more rapid, high-throughput and cost-effective technology that can be tailored for the detection of brewery-specific spoilage organisms from the local environment.

  11. Effect of enhanced UV-B radiation on motile microorganisms

    International Nuclear Information System (INIS)

    Haeder, D.P.

    1985-02-01

    The effect of slightly increased UV-B radiation was studied in four taxonomically very different microorganisms: the gliding prokaryotic cyanobacterium, Phormidium, the unicellular green alga Cosmarium, the flagellate Euglena and the cellular slime mold Dictyostelium. UV-B doses which can be expected as a result of a slight decrease of the protective ozone layer in the stratosphere, do not kill or damage the microorganisms visibly. However, such UV-B doses impair the development, motility and photoorientation of these organisms. Due to the inhibition of these physiological important parameters the organisms cannot respond adequately to the changing factors in their environment, which prevents the survival of the populations. (orig.) [de

  12. Stethoscopes as potential intrahospital carriers of pathogenic microorganisms.

    Science.gov (United States)

    Campos-Murguía, Alejandro; León-Lara, Ximena; Muñoz, Juan M; Macías, Alejandro E; Alvarez, José A

    2014-01-01

    Stethoscopes can take part in the transmission of health care-associated infections. We cultured 112 stethoscopes by direct imprint on blood agar to estimate the prevalence of potentially pathogenic microorganisms. Forty-eight (47%) produced 50 potentially pathogenic microorganisms; from these, 43 (86%) were Staphylococcus aureus, of which 18 (42%) were methicillin-resistant S. aureus. We concluded that stethoscopes should be considered as potential fomites and must be disinfected routinely before and after each patient contact. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  13. Collective Motion of Micro-organisms from Field Theoretical Viewpoint

    OpenAIRE

    Nojiri, Shin'ichi; Kawamura, Masako; Sugamoto, Akio

    1995-01-01

    We analyze the collective motion of micro-organisms in the fluid and consider the problem of the red tide. The red tide is produced by the condensation of the micro-organisms, which might be a similar phenomenon to the condensation of the strings. We propose a model of the generation of the red tide. By considering the interaction between the micro- organisms mediated by the velocity fields in the fluid, we derive the Van der Waals type equation of state, where the generation of the red tide ...

  14. Extremely thermophilic microorganisms and their polymer-hidrolytic enzymes

    Directory of Open Access Journals (Sweden)

    Andrade Carolina M.M.C.

    1999-01-01

    Full Text Available Thermophilic and hyperthermophilic microorganisms are found as normal inhabitants of continental and submarine volcanic areas, geothermally heated sea-sediments and hydrothermal vents and thus are considered extremophiles. Several present or potential applications of extremophilic enzymes are reviewed, especially polymer-hydrolysing enzymes, such as amylolytic and hemicellulolytic enzymes. The purpose of this review is to present the range of morphological and metabolic features among those microorganisms growing from 70oC to 100°C and to indicate potential opportunities for useful applications derived from these features.

  15. 2.3. Global-scale atmospheric dispersion of microorganisms

    Science.gov (United States)

    Griffin, Dale W.; Gonzalez-Martin, Cristina; Hoose, C.; Smith, D.J.; Delort, Anne-Marie; Amato, Pierre

    2018-01-01

    This chapter addresses long-range dispersion and the survival of microorganisms across a wide range of altitudes in Earth's atmosphere. Topics include mechanisms of dispersion, survivability of microorganisms known to be associated with long-range transport, natural and artificial sources of bioaerosols, residence time estimation through the use of proxy aerosols, transport and emission models, and monitoring assays (both culture and molecular based). We conclude with a discussion of the known limits for Earth's biosphere boundary, relating aerobiology studies to planetary exploration given the large degree of overlapping requirements for in situ studies (including low biomass life detection and contamination control).

  16. Biogeochemical linkage between atmosphere and ocean in the eastern equatorial Pacific Ocean: Results from the EqPOS research cruise

    Science.gov (United States)

    Furutani, H.; Inai, Y.; Aoki, S.; Honda, H.; Omori, Y.; Tanimoto, H.; Iwata, T.; Ueda, S.; Miura, K.; Uematsu, M.

    2012-12-01

    atmospheric aerosols such as size distribution, total and cloud condensation nuclei concentrations, particle morphology, bulk and single particle chemical composition were also continuously determined to find out potential link between biogenic VOCs emitted from the ocean and aerosol composition. Biological and biogeochemical characterizations of marine microorganisms, suspended particulate matter, dissolved nutrients in seawater and SML were also conducted. In the presentation, brief overview of the research activities during the EqPOS cruise and biogeochemical linkage atmosphere and ocean via atmospheric and oceanic gaseous and particulate matter from ocean surface to stratosphere observed during the cruise and unique importance of SML would be presented.

  17. Characterisation of microorganisms responsible for EBPR in a ...

    African Journals Online (AJOL)

    The results indicated that micro-organisms were selected by the repeated anaerobic-aerobic process and some non-phosphorus accumulating organisms were eliminated. The cultured strains obtained from acclimated sludges were purified and their DNA was amplified using F27 and R1522 to 1.5 kb; the gene sequences ...

  18. Characterization of the dominant microorganisms responsible for the ...

    African Journals Online (AJOL)

    Nsiho (white kenkey) is a type of kenkey, a sour stiff dumpling, produced from fermented maize meal in Ghana. The dominant microorganisms responsible for the fermentation of nsiho were characterized by analysing samples from four traditional production sites at Anum in the Eastern Region of Ghana. During 48 h of ...

  19. Method and apparatus for detecting micro-organisms

    International Nuclear Information System (INIS)

    Mirsky, J.

    1976-01-01

    A method and apparatus is described for determining the presence and quantity of microorganisms, such as bacteria, fungi and yeast, in a given sample. The apparatus includes two sealed containers, a portion of which may be penetrated by a sharp instrument, as for example, glass vials with flexible septum tops. One container includes a radioactive nutrient medium which is capable of supporting the life process of the microorganism whose presence is being tested. The second container includes a liquid scintillation solution which absorbs the product of metabolism of the organisms. The sample is introduced into the first sealed container, for example, by means of a standard syringe. Any microorganisms present will consume the radioactive nutrient and as a result produce radioactive waste. Means are then applied to penetrate the containers and allow the flow of the radioactive metabolic product from the first container to the second container while preventing any contamination from the ambient. The liquid scintillation solution will emit light in proportion to the amount of the product of metabolism collected from the first container. This light may be detected by standard liquid scintillation counters, thus providing a qualitative and quantitative measure of the microorganism in the tested sample

  20. Methods for identifying lipoxygenase producing microorganisms on agar plates

    NARCIS (Netherlands)

    Nyyssola, A.; Heshof, R.; Haarmann, T.; Eidner, J.; Westerholm-Parvinen, A.; Langfelder, K.; Kruus, K.; Graaff, de L.H.; Buchert, J.

    2012-01-01

    Plate assays for lipoxygenase producing microorganisms on agar plates have been developed. Both potassium iodide-starch and indamine dye formation methods were effective for detecting soybean lipoxygenase activity on agar plates. A positive result was also achieved using the beta-carotene bleaching

  1. Antibiotic cytotoxic effects of microorganisms isolated from Jachymov uranium mines

    Energy Technology Data Exchange (ETDEWEB)

    Fuska, J.; Fuskova, A. (Slovenska Vysoka Skola Technicka, Bratislava (Czechoslovakia). Chemickotechnologicka Fakulta); Jilek, R. (Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia))

    1982-01-01

    Microorganisms were isolated from old relinquished uranium mines in Jachymov; they had been growing for several decades in darkness in temperatures of 5 to 12 degC and relative humidity from 80 to 100%. The concentration of uranium salts in mine waters varied from 10/sup -4/ to 10/sup -5/ g.l/sup -1/, that of Rn in the atmosphere was from 0.04 to 40 Bq.l/sup -1/. Of 324 cultures, 18.8% inhibited the growth of Bacillus subtilis, Escherichia coli and Candida pseudotropicalis and 16.6% that of HeLa cells. The frequency of microorganisms inhibiting the growth of HeLa or Ehrlich ascites cells was markedly higher in this set of cultures than among microorganisms kept in culture collections or isolated from other natural habitats. About 10% of the isolated cultures were mycelia sterilia. The following antibiotics were isolated from microorganisms obtained from uranium mines: frequentin, vermiculin, vermicillin, vermistatin, cytostipin and duclauxin.

  2. Biological characterisation of Haliclona (?gellius) sp.: sponge and associated microorganisms.

    NARCIS (Netherlands)

    Sipkema, D.; Holmes, B.; Nichols, S.A.; Blanch, H.W.

    2009-01-01

    We have characterised the northern Pacific undescribed sponge Haliclona (?gellius) sp. based on rDNA of the sponge and its associated microorganisms. The sponge is closely related to Amphimedon queenslandica from the Great Barrier Reef as the near-complete 18S rDNA sequences of both sponges were

  3. Susceptibility of some oral microorganisms to chlorhexidine and paramonochlorophenol

    OpenAIRE

    Amorim,Crystiane Venditi Gomes do; Aun,Carlos Eduardo; Mayer,Marcia Pinto Alves

    2004-01-01

    Since the use of antimicrobial agents is required in endodontic therapies, this study aimed at determining the minimum inhibitory concentrations (MICs) of chlorhexidine digluconate and paramonochlorophenol (PMC) against microorganisms commonly found in endodontic infections. Both agents were tested by agar dilution tests against Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Candida albicans, Prevotella intermedia, Porphyromonas gingivalis, Porphyromon...

  4. Identification of anaerobic microorganisms for converting kitchen waste to biogas

    International Nuclear Information System (INIS)

    Amirhossein Malakahmad; Shahrom Mohd Zain; Noor Ezlin Ahmad Basri; Shamsul Rahman Mohamed Kutty; Mohd Hasnain Isa

    2010-01-01

    Anaerobic digestion process is one of the alternative methods to convert organic waste into methane gas which is a fuel and energy source. Activities of various kinds of microorganisms are the main factor for anaerobic digestion which produces methane gas. Therefore, in this study a modified Anaerobic Baffled Reactor (ABR) with working volume of 50 liters was designed to identify the microorganisms through biogas production. The mixture of 75% kitchen waste and 25% sewage sludge was used as substrate. Observations on microorganisms in the ABR showed that there exists a small amount of protozoa (5%) and fungi (2%) in the system, but almost 93% of the microorganism population consists of bacteria. It is definitely clear that bacteria are responsible for anaerobic biodegradation of kitchen waste. Results show that in the acidification zone of the ABR (front compartments of reactor) fast growing bacteria capable of growth at high substrate levels and reduced pH was dominant. A shift to slower growing scavenging bacteria that grow better at higher pH was occurring towards the end of the reactor. Due to the ability of activity in acetate environment the percentages of Methanococcus, Methanosarcina and Methanotrix were higher than other kinds of methane former in the system. (Author)

  5. Effects of temperature on biological activity of permafrost microorganisms.

    Science.gov (United States)

    Kalyonova, L F; Novikova, M A; Subbotin, A M; Bazhin, A S

    2015-04-01

    The number and viability of microorganism specimens Bacillus spp. isolated from permafrost soil remained unchanged after incubation at temperatures of -16-37°C. Experiments on F1 CBA/Black-6 mice showed that incubation of bacteria at -5°C for 72 h promotes a decrease in their toxicity and an increase in their immunostimulating effect.

  6. Production of gaba (γ - aminobutyric acid by microorganisms: a review

    Directory of Open Access Journals (Sweden)

    Radhika Dhakal

    2012-12-01

    Full Text Available GABA (γ-aminobutyric acid is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the possibility of providing new health-benefited products enriched with GABA. Synthesis of GABA is catalyzed by glutamate decarboxylase, therefore, the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Major GABA producing microorganisms are lactic acid bacteria (LAB, which make food spoilage pathogens unable to grow and act as probiotics in the gastrointestinal tract. The major factors affecting the production of GABA by microbial fermentation are temperature, pH, fermentation time and different media additives, therefore, these factors are summarized to provide the most up-dated information for effective GABA synthesis. There has been a huge accumulation of knowledge on GABA application for human health accompanying with a demand on natural GABA supply. Only the GABA production by microorganisms can fulfill the demand with GABA-enriched health beneficial foods.

  7. Production of gaba (γ - Aminobutyric acid) by microorganisms: a review.

    Science.gov (United States)

    Dhakal, Radhika; Bajpai, Vivek K; Baek, Kwang-Hyun

    2012-10-01

    GABA (γ-aminobutyric acid) is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the possibility of providing new health-benefited products enriched with GABA. Synthesis of GABA is catalyzed by glutamate decarboxylase, therefore, the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Major GABA producing microorganisms are lactic acid bacteria (LAB), which make food spoilage pathogens unable to grow and act as probiotics in the gastrointestinal tract. The major factors affecting the production of GABA by microbial fermentation are temperature, pH, fermentation time and different media additives, therefore, these factors are summarized to provide the most up-dated information for effective GABA synthesis. There has been a huge accumulation of knowledge on GABA application for human health accompanying with a demand on natural GABA supply. Only the GABA production by microorganisms can fulfill the demand with GABA-enriched health beneficial foods.

  8. Prevalence of pathogenic microorganisms in the oral cavity and their ...

    African Journals Online (AJOL)

    This study was conducted to determine the incidence of pathogenic microorganisms associated with dental caries and antimicrobial susceptibility test of some common dentifrice sold in Kano metropolis. A total of 50 samples were used in this study. The samples were taken using swab from human oral mucosa. The swabs ...

  9. Microorganisms from hands of traditional Chinese medical doctors ...

    African Journals Online (AJOL)

    Background: In a central hospital, the heavy clinical workload makes one to overlook its hazard to health and can to a large extent promote the transmission of pathogenic microorganisms. It is not uncommon however, to observe practices that deviate from normal standards of hygiene. Hand contact between doctors of TCM ...

  10. [Ants as carriers of microorganisms in hospital environments].

    Science.gov (United States)

    Pereira, Rogério Dos Santos; Ueno, Mariko

    2008-01-01

    Concern exists regarding the real possibility of public health threats caused by pathogenic agents that are carried by urban ants. The present study had the objective of isolating and identifying the microorganisms that are associated with ants in hospital environments. One hundred and twenty-five ants of the same species were collected from different units of a university hospital. Each ant was collected using a swab soaked with physiological solution and was transferred to a tube containing brain heart infusion broth and incubated at 35 degrees C for 24 hours. From each tube, with growth, inoculations were made into specific culturing media, to isolate any microorganisms. The ants presented a high capacity for carrying microorganism groups: spore-producing Gram-positive bacilli 63.5%, Gram-negative bacilli 6.3%, Gram-positive cocci 23.1%, filamentous fungi 6.7% and yeast 0.5%. Thus, it can be inferred that ants may be one of the agents responsible for disseminating microorganisms in hospital environments.

  11. Screening of microorganisms for microbial enhanced oil recovery processes

    Energy Technology Data Exchange (ETDEWEB)

    Yonebayashi, H. [Japan National Oil Corp., Tokyo (Japan); Yoshida, S. [Japan Food Research Laboratiories, Tokyo (Japan). Div. of Microbiology; Ono, K. [Japan National Oil Corp., Chiba (Japan). Tech. Research Center; Enomoto, H. [Tohoku University, Sendai (Japan). Dept. of Geoscience and Tech.

    2000-01-01

    The objective of this study is to screen effective microorganisms for the Microbial Enhanced Oil Recovery process (or simply as MEOR). Samples of drilling cuttings, formation water, and soil were collected from domestic drilling sites and oil fields. Moreover, samples of activated-sludge and compost were collected from domestic sewage treatment facility and food treatment facility. At first, microorganisms in samples were investigated by incubation with different media; then they were isolated. By two stage-screening based on metabolizing ability, 4 strains (Bacillus licheniformis TRC-18-2-a, Enterobacter cloacae TRC-322, Bacillus subtilis TRC-4118, and Bacillus subtilis TRC-4126) were isolated as effective microorganisms for oil recovery. B. licheniformis TRC-18-2-a is a multifunctional microorganism possessing excellent surfactant productivity, and in addition it has gas, acid and polymer productivities. E. cloacae TRC-332 has gas and acid producing abilities. B. subtilis TRC-4118 and TRC-4126 are effective biosurfactant producers, and they reduce the interfacial tension to 0.04 and 0.12 dyne/cm, respectively. (author)

  12. Is arsenic biotransformation a detoxification mechanism for microorganisms?

    International Nuclear Information System (INIS)

    Rahman, M. Azizur; Hassler, Christel

    2014-01-01

    Arsenic (As) is extremely toxic to living organisms at high concentration. In aquatic systems, As exists in different chemical forms. The two major inorganic As (iAs) species are As V , which is thermodynamically stable in oxic waters, and As III , which is predominant in anoxic conditions. Photosynthetic microorganisms (e.g., phytoplankton and cyanobacteria) take up As V , biotransform it to As III , then biomethylate it to methylarsenic (MetAs) forms. Although As III is more toxic than As V , As III is much more easily excreted from the cells than As V . Therefore, majority of researchers consider the reduction of As V to As III as a detoxification process. The biomethylation process results in the conversion of toxic iAs to the less toxic pentavalent MetAs forms (monomethylarsonate; MMA V , dimethylarsonate; DMA V , and trimethylarsenic oxide; TMAO V ) and trimethylarsine (TMAO III ). However, biomethylation by microorganisms also produces monomethylarsenite (MMA III ) and dimethylarsenite (DMA III ), which are more toxic than iAs, as a result of biomethylation by the microorganisms, demonstrates the need to reconsider to what extent As biomethylation contributes to a detoxification process. In this review, we focused on the discussion of whether the biotransformation of As species in microorganisms is really a detoxification process with recent data

  13. Effect of effective microorganisms on broiler chicken performance ...

    African Journals Online (AJOL)

    A study was conducted between January and March 2001 to assess the effects of Effective Microorganisms (EM) as feed additive in broiler chicken production on growth performance. The experiment involved 210 day-old broiler chicks which were randomly allocated to 14 pens of 15 birds each. There were seven ...

  14. Plant Growth-Promoting Microorganisms for Environmental Sustainability.

    Science.gov (United States)

    Abhilash, P C; Dubey, Rama Kant; Tripathi, Vishal; Gupta, Vijai K; Singh, Harikesh B

    2016-11-01

    Agrochemicals used to meet the needs of a rapidly growing human population can deteriorate the quality of ecosystems and are not affordable to farmers in low-resource environments. Here, we propose the use of plant growth-promoting microorganisms (PGPMs) as a tool for sustainable food production without compromising ecosystems services. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Some estimates of the continuous cultivation of microorganisms

    Directory of Open Access Journals (Sweden)

    G. V. Alekseev

    2017-01-01

    Full Text Available The proteins, fats and carbohydrates received by the person traditionally from animal and vegetable sources don't cover all increasing needs of mankind any more today. At the same time proteins and fats of microorganisms with success can replace proteins and fats of a traditional origin. As protein producers microorganisms at the high content of protein in biomass and high growth rate of microorganisms have certain advantages. The present article is devoted to questions of numerical modeling of processes of cultivation of microorganisms. On the basis of the known model offered Mono in which saturation of growth rate of culture at increase in initial concentration of a substratum of S0 is considered the system of the differential equations describing the happening processes in that number before achievement of stationarity is written down. At the same time dependence of separate sizes, the systems entering the equations is insufficiently studied at change of parameters of process. The behavior of all system at violation of regulations is of interest or at unauthorized change of one of parameters. For studying of these questions numerical modeling is carried out and the basic picture of change of chemostate curves in these conditions is received

  16. General Purpose Segmentation for Microorganisms in Microscopy Images

    DEFF Research Database (Denmark)

    Jensen, Sebastian H. Nesgaard; Moeslund, Thomas B.; Rankl, Christian

    2014-01-01

    In this paper, we propose an approach for achieving generalized segmentation of microorganisms in mi- croscopy images. It employs a pixel-wise classification strategy based on local features. Multilayer percep- trons are utilized for classification of the local features and is trained for each sp...

  17. Is arsenic biotransformation a detoxification mechanism for microorganisms?

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, M. Azizur, E-mail: Mohammad.Rahman@uts.edu.au [Centre for Environmental Sustainability, School of the Environment, Faculty of Science, University of Technology, P.O. Box 123, Broadway, Sydney, NSW 2007 (Australia); Hassler, Christel [Marine and Lake Biogeochemistry, Institute F. A. Forel, University of Geneva, 10 rte de Suisse, Versoix, 1290 Switzerland (Switzerland)

    2014-01-15

    Arsenic (As) is extremely toxic to living organisms at high concentration. In aquatic systems, As exists in different chemical forms. The two major inorganic As (iAs) species are As{sup V}, which is thermodynamically stable in oxic waters, and As{sup III}, which is predominant in anoxic conditions. Photosynthetic microorganisms (e.g., phytoplankton and cyanobacteria) take up As{sup V}, biotransform it to As{sup III}, then biomethylate it to methylarsenic (MetAs) forms. Although As{sup III} is more toxic than As{sup V}, As{sup III} is much more easily excreted from the cells than As{sup V}. Therefore, majority of researchers consider the reduction of As{sup V} to As{sup III} as a detoxification process. The biomethylation process results in the conversion of toxic iAs to the less toxic pentavalent MetAs forms (monomethylarsonate; MMA{sup V}, dimethylarsonate; DMA{sup V}, and trimethylarsenic oxide; TMAO{sup V}) and trimethylarsine (TMAO{sup III}). However, biomethylation by microorganisms also produces monomethylarsenite (MMA{sup III}) and dimethylarsenite (DMA{sup III}), which are more toxic than iAs, as a result of biomethylation by the microorganisms, demonstrates the need to reconsider to what extent As biomethylation contributes to a detoxification process. In this review, we focused on the discussion of whether the biotransformation of As species in microorganisms is really a detoxification process with recent data.

  18. Isolation and identification of the microorganisms most prevalent in ...

    African Journals Online (AJOL)

    Infections of the external eye account for a significant percentage of ocular inflammations, some of which lead to visual losses as result of corneal involvement. This study purely isolated and identified the microorganisms most prevalent in external eye infections in Owerri urban (as seen Mercy Eye clinic). With the aid of ...

  19. Fossil Microorganisms in Archaean deposits of Northern Karelia

    Science.gov (United States)

    Astafieva, M. M.; Hoover, R. B.; Rozanov, A. Y.; Vrevskiy, A. B.

    2005-01-01

    Newly found biomorphic microstructures from the Upper Archaean (lopian) rocks from Northern Karelia are described. The presence of various microorganisms of bacterial nature and even cyanobacteria (and possibly eukaryotic forms) is suggested. The necessity of employing methods of electron microscopy, as well as traditional methods, while studying the very early manifestations of life in Archaean and Early Proterozoic is noted.

  20. Fossil Microorganisms and Formation of Early Precambrian Weathering Profiles

    Science.gov (United States)

    Rozanov, A. Yu; Astafieva, M. M.; Vrevsky, A. B.; Alfimova, N. A.; Matrenichev, V. A.; Hoover, R. B.

    2009-01-01

    Weathering crusts are the only reliable evidences of the existence of continental conditions. Often they are the only source of information about exogenous processes and subsequently about conditions under which the development of the biosphere occurred. A complex of diverse fossil microorganisms was discovered as a result of Scanning Electron Microscope investigations. The chemical composition of the discovered fossils is identical to that of the host rocks and is represented by Si, Al, Fe, Ca and Mg. Probably, the microorganisms fixed in rocks played the role of catalyst. The decomposition of minerals comprising the rocks and their transformation into clayey (argillaceous) minerals, most likely occurred under the influence of microorganisms. And may be unique weathering crusts of Early Precambrian were formed due to interaction between specific composition of microorganism assemblage and conditions of hypergene transformations. So it is possible to speak about colonization of land by microbes already at that time and about existence of single raw from weathering crusts (Primitive soils) to real soils.

  1. Engineering of microorganisms towards recovery of rare metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, Kouichi; Ueda, Mitsuyoshi [Kyoto Univ. (Japan). Div. of Applied Life Sciences

    2010-06-15

    The bioadsorption of metal ions using microorganisms is an attractive technology for the recovery of rare metal ions as well as removal of toxic heavy metal ions from aqueous solution. In initial attempts, microorganisms with the ability to accumulate metal ions were isolated from nature and intracellular accumulation was enhanced by the overproduction of metal-binding proteins in the cytoplasm. As an alternative, the cell surface design of microorganisms by cell surface engineering is an emerging strategy for bioadsorption and recovery of metal ions. Cell surface engineering was firstly applied to the construction of a bioadsorbent to adsorb heavy metal ions for bioremediation. Cell surface adsorption of metal ions is rapid and reversible. Therefore, adsorbed metal ions can be easily recovered without cell breakage, and the bioadsorbent can be reused or regenerated. These advantages are suitable for the recovery of rare metal ions. Actually, the cell surface display of a molybdate-binding protein on yeast led to the enhanced adsorption of molybdate, one of the rare metal ions. An additional advantage is that the cell surface display system allows high-throughput screening of protein/peptide libraries owing to the direct evaluation of the displayed protein/peptide without purification and concentration. Therefore, the creation of novel metal-binding protein/ peptide and engineering of microorganisms towards the recovery of rare metal ions could be simultaneously achieved. (orig.)

  2. Rate of biodegradation of crude oil by microorganisms isolated from ...

    African Journals Online (AJOL)

    The rate of biodegradation of crude oil by micro-organisms isolated from crude oil sludge environment in Eket, Akwa Ibom State of Nigeria was studied. Mineral salt medium supplemented with crude oil was used and three most abundant species isolated from a crude oil sludged soil - Micrococcus varians, Bacillus subtilis ...

  3. [Long-term storage of obligate anaerobic microorganisms in glycerol].

    Science.gov (United States)

    Briukhanov, A I; Netrusov, A I

    2006-01-01

    We evaluated the possibility of storing the cultures of obligate anaerobic microorganisms (clostridia. acetogenic and sulfate-reducing bacteria, and methanogenic archaea) in 25% glycerol at -70 degrees C for a long time (up to 3 years). This method of storage is adequate to preserve cell viability in most obligate anaerobes.

  4. Mitigating cyanobacterial blooms: how effective are 'effective microorganisms'?

    NARCIS (Netherlands)

    Lürling, M.F.L.L.W.; Tolman, Y.; Euwe, M.

    2009-01-01

    This study examined the effects of 'Effective Microorganisms (EM)' on the growth of cyanobacteria, and their ability to terminate cyanobacterial blooms. The EM was tested in the form of 'mudballs' or 'Bokashi-balls', and as a suspension (EM-A) in laboratory experiments. No growth inhibition was

  5. Production of effective microorganism using halal- based sources: A ...

    African Journals Online (AJOL)

    GREGORY

    2011-12-16

    Dec 16, 2011 ... Key words: Component, effective microorganisms (EM), agriculture, halal-based source. INTRODUCTION. In recent years, with focus on feeding a rapidly growing human population, Malaysia has jeopardized the environ- ment and its natural resources, which are already under great stress. Consequently ...

  6. Color-Removal by Microorganisms Isolated from Human Hands

    Directory of Open Access Journals (Sweden)

    Tsukasa Ito

    2013-08-01

    Full Text Available Microorganisms are essential for human life. Microorganisms decompose the carbon compounds in dead animals and plants and convert them into carbon dioxide. Intestinal bacteria assist in food digestion. Some vitamins are produced by bacteria that live in the intestines. Sewage and industrial wastewater are treated by activated sludge composed of microbial communities. All of these are due to the ability of microbes to produce many enzymes that can degrade chemicals. How do teachers make students understand that microorganisms are always associated with humans, and that microorganisms have the ability to degrade chemicals? The presence of microorganisms on humans can be shown by incubating agar plates after they are touched by the hands of students. The ability of microorganisms to degrade chemicals can be shown by an analytical measurement of the degradation of chemicals. When the chemicals are dyes (colorants in water, microbial activity on degradation of dyes can be demonstrated by observing a decreasing degree of color as a result of the enzymatic activity (e.g., azoreductase. Dyes are widely used in the textile, food, and cosmetic industries. They are generally resistant to conventional biological wastewater treatment systems such as the activated sludge process (4. The discharge of wastewater containing dye pollutes surface water. The ability of microorganisms to decolorize and degrade dyes has been widely investigated to use for bioremediation purposes (5. The goal of this tip is to understand the presence of bacteria on human skin and the ability of bacteria to degrade colorant chemicals (decolorization. In this tip, students first cultivate and isolate bacteria on their hands, and then examine potential decolorization activity of each bacterium by observing the degree of color of the liquid in tubes in which bacteria isolated from students’ hands were inoculated. Decolorization activity of bacterial isolates from human skin has been

  7. Oceans and Coasts

    Science.gov (United States)

    An overview of EPA’s oceans, coasts, estuaries and beaches programs and the regulatory (permits/rules) and non-regulatory approaches for managing their associated environmental issues, such as water pollution and climate change.

  8. Ocean Dumping: International Treaties

    Science.gov (United States)

    The London Convention and London Protocol are global treaties to protect the marine environment from pollution caused by the ocean dumping of wastes. The Marine, Protection, Research and Sanctuaries Act implements the requirements of the LC.

  9. Ocean Technology Development Tank

    Data.gov (United States)

    Federal Laboratory Consortium — The new SWFSC laboratory in La Jolla incorporates a large sea- and fresh-water Ocean Technology Development Tank. This world-class facility expands NOAA's ability to...

  10. Loggerhead oceanic stage duration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study involves analysis of skeletal growth marks in humerus bones of 222 juvenile loggerhead sea turtles (Caretta caretta) stranded dead along the Atlantic US...

  11. Ocean iron fertilization

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.; Smetacek, V.

    In 2009 and 2010, an Indo-German scientific expedition dusted the ocean with iron to stimulate the biological pump that captures atmosphereic carbon dioxide. Two onboard scientists tell the story of this controversial project. Besides raising...

  12. Ocean Dumping Control Regulations

    International Nuclear Information System (INIS)

    1978-01-01

    These Regulations were made further to the Ocean Dumping Control Act which provides for restrictions in dumping operations. The Regulations contain model applications for permits to dump or load a series of materials. (NEA)

  13. Volcanic signals in oceans

    KAUST Repository

    Stenchikov, Georgiy L.; Delworth, Thomas L.; Ramaswamy, V.; Stouffer, Ronald J.; Wittenberg, Andrew; Zeng, Fanrong

    2009-01-01

    Sulfate aerosols resulting from strong volcanic explosions last for 2–3 years in the lower stratosphere. Therefore it was traditionally believed that volcanic impacts produce mainly short-term, transient climate perturbations. However, the ocean

  14. Modelling the Ozone-Based Treatments for Inactivation of Microorganisms

    Directory of Open Access Journals (Sweden)

    Agnieszka Joanna Brodowska

    2017-10-01

    Full Text Available The paper presents the development of a model for ozone treatment in a dynamic bed of different microorganisms (Bacillus subtilis, B. cereus, B. pumilus, Escherichia coli, Pseudomonas fluorescens, Aspergillus niger, Eupenicillium cinnamopurpureum on a heterogeneous matrix (juniper berries, cardamom seeds initially treated with numerous ozone doses during various contact times was studied. Taking into account various microorganism susceptibility to ozone, it was of great importance to develop a sufficiently effective ozone dose to preserve food products using different strains based on the microbial model. For this purpose, we have chosen the Weibull model to describe the survival curves of different microorganisms. Based on the results of microorganism survival modelling after ozone treatment and considering the least susceptible strains to ozone, we selected the critical ones. Among tested strains, those from genus Bacillus were recognized as the most critical strains. In particular, B. subtilis and B. pumilus possessed the highest resistance to ozone treatment because the time needed to achieve the lowest level of its survival was the longest (up to 17.04 min and 16.89 min for B. pumilus reduction on juniper berry and cardamom seed matrix, respectively. Ozone treatment allow inactivate microorganisms to achieving lower survival rates by ozone dose (20.0 g O3/m3 O2, with a flow rate of 0.4 L/min and contact time (up to 20 min. The results demonstrated that a linear correlation between parameters p and k in Weibull distribution, providing an opportunity to calculate a fitted equation of the process.

  15. Potential applications of plant probiotic microorganisms in agriculture and forestry

    Directory of Open Access Journals (Sweden)

    Luciana Porto de Souza Vandenberghe

    2017-07-01

    Full Text Available Agriculture producers, pushed by the need for high productivity, have stimulated the intensive use of pesticides and fertilizers. Unfortunately, negative effects on water, soil, and human and animal health have appeared as a consequence of this indiscriminate practice. Plant probiotic microorganisms (PPM, also known as bioprotectants, biocontrollers, biofertilizers, or biostimulants, are beneficial microorganisms that offer a promising alternative and reduce health and environmental problems. These microorganisms are involved in either a symbiotic or free-living association with plants and act in different ways, sometimes with specific functions, to achieve satisfactory plant development. This review deals with PPM presentation and their description and function in different applications. PPM includes the plant growth promoters (PGP group, which contain bacteria and fungi that stimulate plant growth through different mechanisms. Soil microflora mediate many biogeochemical processes. The use of plant probiotics as an alternative soil fertilization source has been the focus of several studies; their use in agriculture improves nutrient supply and conserves field management and causes no adverse effects. The species related to organic matter and pollutant biodegradation in soil and abiotic stress tolerance are then presented. As an important way to understand not only the ecological role of PPM and their interaction with plants but also the biotechnological application of these cultures to crop management, two main approaches are elucidated: the culture-dependent approach where the microorganisms contained in the plant material are isolated by culturing and are identified by a combination of phenotypic and molecular methods; and the culture-independent approach where microorganisms are detected without cultivating them, based on extraction and analyses of DNA. These methods combine to give a thorough knowledge of the microbiology of the studied

  16. Halophilic microorganisms in deteriorated historic buildings: insights into their characteristics.

    Science.gov (United States)

    Adamiak, Justyna; Otlewska, Anna; Gutarowska, Beata; Pietrzak, Anna

    2016-01-01

    Historic buildings are constantly being exposed to numerous climatic changes such as damp and rainwater. Water migration into and out of the material's pores can lead to salt precipitation and the so-called efflorescence. The structure of the material may be seriously threatened by salt crystallization. A huge pressure is produced when salt hydrates occupy larger spaces, which leads at the end to cracking, detachment and material loss. Halophilic microorganisms have the ability to adapt to high salinity because of the mechanisms of inorganic salt (KCl or NaCl) accumulation in their cells at concentrations isotonic to the environment, or compatible solutes uptake or synthesis. In this study, we focused our attention on the determination of optimal growth conditions of halophilic microorganisms isolated from historical buildings in terms of salinity, pH and temperature ranges, as well as biochemical properties and antagonistic abilities. Halophilic microorganisms studied in this paper could be categorized as a halotolerant group, as they grow in the absence of NaCl, as well as tolerate higher salt concentrations (Staphylococcus succinus, Virgibacillus halodenitrificans). Halophilic microorganisms have been also observed (Halobacillus styriensis, H. hunanensis, H. naozhouensis, H. litoralis, Marinococcus halophilus and yeast Sterigmatomyces halophilus). With respect to their physiological characteristics, cultivation at a temperature of 25-30°C, pH 6-7, NaCl concentration for halotolerant and halophilic microorganisms, 0-10% and 15-30%, respectively, provides the most convenient conditions. Halophiles described in this study displayed lipolytic, glycolytic and proteolytic activities. Staphylococcus succinus and Marinococcus halophilus showed strong antagonistic potential towards bacteria from the Bacillus genus, while Halobacillus litoralis displayed an inhibiting ability against other halophiles.

  17. Modelling the Ozone-Based Treatments for Inactivation of Microorganisms

    Science.gov (United States)

    Brodowska, Agnieszka Joanna; Nowak, Agnieszka; Kondratiuk-Janyska, Alina; Piątkowski, Marcin; Śmigielski, Krzysztof

    2017-01-01

    The paper presents the development of a model for ozone treatment in a dynamic bed of different microorganisms (Bacillus subtilis, B. cereus, B. pumilus, Escherichia coli, Pseudomonas fluorescens, Aspergillus niger, Eupenicillium cinnamopurpureum) on a heterogeneous matrix (juniper berries, cardamom seeds) initially treated with numerous ozone doses during various contact times was studied. Taking into account various microorganism susceptibility to ozone, it was of great importance to develop a sufficiently effective ozone dose to preserve food products using different strains based on the microbial model. For this purpose, we have chosen the Weibull model to describe the survival curves of different microorganisms. Based on the results of microorganism survival modelling after ozone treatment and considering the least susceptible strains to ozone, we selected the critical ones. Among tested strains, those from genus Bacillus were recognized as the most critical strains. In particular, B. subtilis and B. pumilus possessed the highest resistance to ozone treatment because the time needed to achieve the lowest level of its survival was the longest (up to 17.04 min and 16.89 min for B. pumilus reduction on juniper berry and cardamom seed matrix, respectively). Ozone treatment allow inactivate microorganisms to achieving lower survival rates by ozone dose (20.0 g O3/m3 O2, with a flow rate of 0.4 L/min) and contact time (up to 20 min). The results demonstrated that a linear correlation between parameters p and k in Weibull distribution, providing an opportunity to calculate a fitted equation of the process. PMID:28991199

  18. IODE OceanTeacher

    OpenAIRE

    Brown, M.; Pikula, L.; Reed, G.

    2002-01-01

    The OceanTeacher website and CD-ROM publication have proven to be powerful and flexible tools for marine data and information management training. There are two segments of OceanTeacher: marine data management and marine information management. The IODE trainers have created an encyclopedic Resource Kit covering all aspects of the subjects. Through continual updates, the Kit provides the latest versions of popular public-domain software, documentation for global and regional datasets, docu...

  19. Modeling of oceanic vortices

    Science.gov (United States)

    Cushman-Roisin, B.

    Following on a tradition of biannual meetings, the 5th Colloquium on the Modeling of Oceanic Vortices was held May 21-23, 1990, at the Thayer School of Engineering at Dartmouth College, Hanover, N.H. The colloquium series, sponsored by the Office of Naval Research, is intended to gather oceanographers who contribute to our understanding of oceanic mesoscale vortices via analytical, numerical and experimental modeling techniques.

  20. Wind Generated Ocean Waves

    DEFF Research Database (Denmark)

    Frigaard, Peter

    2001-01-01

    Book review: I. R. Young, Elsevier Ocean Engineering Series, Vol 2. Elsevier Science, Oxford, UK, 1999, 306 pages, hardbound, ISBN 0-08-043317-0, Dfl. 275,00 (US$ 139.50)......Book review: I. R. Young, Elsevier Ocean Engineering Series, Vol 2. Elsevier Science, Oxford, UK, 1999, 306 pages, hardbound, ISBN 0-08-043317-0, Dfl. 275,00 (US$ 139.50)...

  1. The Ocean: Our Future

    Science.gov (United States)

    Independent World Commission On The Oceans; Soares, Mario

    1998-09-01

    The Ocean, Our Future is the official report of the Independent World Commission on the Oceans, chaired by Mário Soares, former President of Portugal. Its aim is to summarize the very real problems affecting the ocean and its future management, and to provide imaginative solutions to these various and interlocking problems. The oceans have traditionally been taken for granted as a source of wealth, opportunity and abundance. Our growing understanding of the oceans has fundamentally changed this perception. We now know that in some areas, abundance is giving way to real scarcity, resulting in severe conflicts. Territorial disputes that threaten peace and security, disruptions to global climate, overfishing, habitat destruction, species extinction, indiscriminate trawling, pollution, the dumping of hazardous and toxic wastes, piracy, terrorism, illegal trafficking and the destruction of coastal communities are among the problems that today form an integral part of the unfolding drama of the oceans. Based on the deliberations, experience and input of more than 100 specialists from around the world, this timely volume provides a powerful overview of the state of our water world.

  2. Volcanic signals in oceans

    KAUST Repository

    Stenchikov, Georgiy L.

    2009-08-22

    Sulfate aerosols resulting from strong volcanic explosions last for 2–3 years in the lower stratosphere. Therefore it was traditionally believed that volcanic impacts produce mainly short-term, transient climate perturbations. However, the ocean integrates volcanic radiative cooling and responds over a wide range of time scales. The associated processes, especially ocean heat uptake, play a key role in ongoing climate change. However, they are not well constrained by observations, and attempts to simulate them in current climate models used for climate predictions yield a range of uncertainty. Volcanic impacts on the ocean provide an independent means of assessing these processes. This study focuses on quantification of the seasonal to multidecadal time scale response of the ocean to explosive volcanism. It employs the coupled climate model CM2.1, developed recently at the National Oceanic and Atmospheric Administration\\'s Geophysical Fluid Dynamics Laboratory, to simulate the response to the 1991 Pinatubo and the 1815 Tambora eruptions, which were the largest in the 20th and 19th centuries, respectively. The simulated climate perturbations compare well with available observations for the Pinatubo period. The stronger Tambora forcing produces responses with higher signal-to-noise ratio. Volcanic cooling tends to strengthen the Atlantic meridional overturning circulation. Sea ice extent appears to be sensitive to volcanic forcing, especially during the warm season. Because of the extremely long relaxation time of ocean subsurface temperature and sea level, the perturbations caused by the Tambora eruption could have lasted well into the 20th century.

  3. A possible role of ground-based microorganisms on cloud formation in the atmosphere

    Science.gov (United States)

    Ekström, S.; Nozière, B.; Hultberg, M.; Alsberg, T.; Magnér, J.; Nilsson, E. D.; Artaxo, P.

    2010-01-01

    The formation of clouds is an important process for the atmosphere, the hydrological cycle, and climate, but some aspects of it are not completely understood. In this work, we show that microorganisms might affect cloud formation without leaving the Earth's surface by releasing biological surfactants (or biosurfactants) in the environment, that make their way into atmospheric aerosols and could significantly enhance their activation into cloud droplets. In the first part of this work, the cloud-nucleating efficiency of standard biosurfactants was characterized and found to be better than that of any aerosol material studied so far, including inorganic salts. These results identify molecular structures that give organic compounds exceptional cloud-nucleating properties. In the second part, atmospheric aerosols were sampled at different locations: a temperate coastal site, a marine site, a temperate forest, and a tropical forest. Their surface tension was measured and found to be below 30 mN/m, the lowest reported for aerosols, to our knowledge. This very low surface tension was attributed to the presence of biosurfactants, the only natural substances able to reach to such low values. The presence of strong microbial surfactants in aerosols would be consistent with the organic fractions of exceptional cloud-nucleating efficiency recently found in aerosols, and with the correlations between algae bloom and cloud cover reported in the Southern Ocean. The results of this work also suggest that biosurfactants might be common in aerosols and thus of global relevance. If this is confirmed, a new role for microorganisms on the atmosphere and climate could be identified.

  4. Impacts of Ocean Acidification

    Energy Technology Data Exchange (ETDEWEB)

    Bijma, Jelle (Alfred Wegener Inst., D-27570 Bremerhaven (Germany)) (and others)

    2009-08-15

    There is growing scientific evidence that, as a result of increasing anthropogenic carbon dioxide (CO{sub 2}) emissions, absorption of CO{sub 2} by the oceans has already noticeably increased the average oceanic acidity from pre-industrial levels. This global threat requires a global response. According to the Intergovernmental Panel on Climate Change (IPCC), continuing CO{sub 2} emissions in line with current trends could make the oceans up to 150% more acidic by 2100 than they were at the beginning of the Anthropocene. Acidification decreases the ability of the ocean to absorb additional atmospheric CO{sub 2}, which implies that future CO{sub 2} emissions are likely to lead to more rapid global warming. Ocean acidification is also problematic because of its negative effects on marine ecosystems, especially marine calcifying organisms, and marine resources and services upon which human societies largely depend such as energy, water, and fisheries. For example, it is predicted that by 2100 around 70% of all cold-water corals, especially those in the higher latitudes, will live in waters undersaturated in carbonate due to ocean acidification. Recent research indicates that ocean acidification might also result in increasing levels of jellyfish in some marine ecosystems. Aside from direct effects, ocean acidification together with other global change-induced impacts such as marine and coastal pollution and the introduction of invasive alien species are likely to result in more fragile marine ecosystems, making them more vulnerable to other environmental impacts resulting from, for example, coastal deforestation and widescale fisheries. The Marine Board-ESF Position Paper on the Impacts of Climate Change on the European Marine and Coastal Environment - Ecosystems indicated that presenting ocean acidification issues to policy makers is a key issue and challenge. Indeed, as the consequences of ocean acidification are expected to emerge rapidly and drastically, but are

  5. In situ determination of the reduction levels of cytochromes b and c in growing bacteria : a case study with N2-fixing Azorhizobium caulinodans

    NARCIS (Netherlands)

    Pronk, A.F.; Boogerd, F C; Stoof, C.; Oltmann, L F; Stouthamer, A.H.; van Verseveld, H W

    1993-01-01

    The determination of the in situ reduction levels of cytochromes b and c in growing bacteria is achieved by coupling a chemostat with a dual wavelength spectrophotometer. Visible light absorption spectra of cytochromes present in bacterial cells actively growing in a chemostat at a specific growth

  6. Complete genome sequence of the N2-fixing broad host range endophyte Klebsiella pneumoniae 342 and virulence predictions verified in mice.

    Directory of Open Access Journals (Sweden)

    Derrick E Fouts

    2008-07-01

    Full Text Available We report here the sequencing and analysis of the genome of the nitrogen-fixing endophyte, Klebsiella pneumoniae 342. Although K. pneumoniae 342 is a member of the enteric bacteria, it serves as a model for studies of endophytic, plant-bacterial associations due to its efficient colonization of plant tissues (including maize and wheat, two of the most important crops in the world, while maintaining a mutualistic relationship that encompasses supplying organic nitrogen to the host plant. Genomic analysis examined K. pneumoniae 342 for the presence of previously identified genes from other bacteria involved in colonization of, or growth in, plants. From this set, approximately one-third were identified in K. pneumoniae 342, suggesting additional factors most likely contribute to its endophytic lifestyle. Comparative genome analyses were used to provide new insights into this question. Results included the identification of metabolic pathways and other features devoted to processing plant-derived cellulosic and aromatic compounds, and a robust complement of transport genes (15.4%, one of the highest percentages in bacterial genomes sequenced. Although virulence and antibiotic resistance genes were predicted, experiments conducted using mouse models showed pathogenicity to be attenuated in this strain. Comparative genomic analyses with the presumed human pathogen K. pneumoniae MGH78578 revealed that MGH78578 apparently cannot fix nitrogen, and the distribution of genes essential to surface attachment, secretion, transport, and regulation and signaling varied between each genome, which may indicate critical divergences between the strains that influence their preferred host ranges and lifestyles (endophytic plant associations for K. pneumoniae 342 and presumably human pathogenesis for MGH78578. Little genome information is available concerning endophytic bacteria. The K. pneumoniae 342 genome will drive new research into this less-understood, but important category of bacterial-plant host relationships, which could ultimately enhance growth and nutrition of important agricultural crops and development of plant-derived products and biofuels.

  7. Complete genome sequence of N2-fixing model strain Klebsiella sp. nov. M5al, which produces plant cell wall-degrading enzymes and siderophores

    Directory of Open Access Journals (Sweden)

    Zhili Yu

    2018-03-01

    Full Text Available The bacterial strain M5al is a model strain for studying the molecular genetics of N2-fixation and molecular engineering of microbial production of platform chemicals 1,3-propanediol and 2,3-butanediol. Here, we present the complete genome sequence of the strain M5al, which belongs to a novel species closely related to Klebsiella michiganensis. M5al secretes plant cell wall-degrading enzymes and colonizes rice roots but does not cause soft rot disease. M5al also produces siderophores and contains the gene clusters for synthesis and transport of yersiniabactin which is a critical virulence factor for Klebsiella pathogens in causing human disease. We propose that the model strain M5al can be genetically modified to study bacterial N2-fixation in association with non-legume plants and production of 1,3-propanediol and 2,3-butanediol through degradation of plant cell wall biomass.

  8. N2 fixing alder (Alnus viridis spp.fruticosa) effects on soil properties across a secondary successional chronosequence in interior Alaska

    Science.gov (United States)

    Jennifer S. Mitchell; Roger W. Ruess

    2009-01-01

    Green alder (Alnus viridis ssp. fruticosa) is a dominant understory shrub during secondary successional development of upland forests throughout interior Alaska, where it contributes substantially to the nitrogen (N) economy through atmospheric N2 fixation. Across a replicated 200+ year old vegetation...

  9. Calculation of the radiative properties of photosynthetic microorganisms

    International Nuclear Information System (INIS)

    Dauchet, Jérémi; Blanco, Stéphane; Cornet, Jean-François; Fournier, Richard

    2015-01-01

    A generic methodological chain for the predictive calculation of the light-scattering and absorption properties of photosynthetic microorganisms within the visible spectrum is presented here. This methodology has been developed in order to provide the radiative properties needed for the analysis of radiative transfer within photobioreactor processes, with a view to enable their optimization for large-scale sustainable production of chemicals for energy and chemistry. It gathers an electromagnetic model of light-particle interaction along with detailed and validated protocols for the determination of input parameters: morphological and structural characteristics of the studied microorganisms as well as their photosynthetic-pigment content. The microorganisms are described as homogeneous equivalent-particles whose shape and size distribution is characterized by image analysis. The imaginary part of their refractive index is obtained thanks to a new and quite extended database of the in vivo absorption spectra of photosynthetic pigments (that is made available to the reader). The real part of the refractive index is then calculated by using the singly subtractive Kramers–Krönig approximation, for which the anchor point is determined with the Bruggeman mixing rule, based on the volume fraction of the microorganism internal-structures and their refractive indices (extracted from a database). Afterwards, the radiative properties are estimated using the Schiff approximation for spheroidal or cylindrical particles, as a first step toward the description of the complexity and diversity of the shapes encountered within the microbial world. Finally, these predictive results are confronted to experimental normal-hemispherical transmittance spectra for validation. This entire procedure is implemented for Rhodospirillum rubrum, Arthrospira platensis and Chlamydomonas reinhardtii, each representative of the main three kinds of photosynthetic microorganisms, i.e. respectively

  10. Calculation of the radiative properties of photosynthetic microorganisms

    Science.gov (United States)

    Dauchet, Jérémi; Blanco, Stéphane; Cornet, Jean-François; Fournier, Richard

    2015-08-01

    A generic methodological chain for the predictive calculation of the light-scattering and absorption properties of photosynthetic microorganisms within the visible spectrum is presented here. This methodology has been developed in order to provide the radiative properties needed for the analysis of radiative transfer within photobioreactor processes, with a view to enable their optimization for large-scale sustainable production of chemicals for energy and chemistry. It gathers an electromagnetic model of light-particle interaction along with detailed and validated protocols for the determination of input parameters: morphological and structural characteristics of the studied microorganisms as well as their photosynthetic-pigment content. The microorganisms are described as homogeneous equivalent-particles whose shape and size distribution is characterized by image analysis. The imaginary part of their refractive index is obtained thanks to a new and quite extended database of the in vivo absorption spectra of photosynthetic pigments (that is made available to the reader). The real part of the refractive index is then calculated by using the singly subtractive Kramers-Krönig approximation, for which the anchor point is determined with the Bruggeman mixing rule, based on the volume fraction of the microorganism internal-structures and their refractive indices (extracted from a database). Afterwards, the radiative properties are estimated using the Schiff approximation for spheroidal or cylindrical particles, as a first step toward the description of the complexity and diversity of the shapes encountered within the microbial world. Finally, these predictive results are confronted to experimental normal-hemispherical transmittance spectra for validation. This entire procedure is implemented for Rhodospirillum rubrum, Arthrospira platensis and Chlamydomonas reinhardtii, each representative of the main three kinds of photosynthetic microorganisms, i.e. respectively

  11. Ocean Physicochemistry versus Climate Change

    OpenAIRE

    Góralski, Bogdan

    2014-01-01

    It is the dwindling ocean productivity which leaves dissolved carbon dioxide in the seawater. Its solubility is diminished by the rise in ocean water temperature (by one degree Celsius since 1910, according to IPCC). Excess carbon dioxide is emitted into the atmosphere, while its growing concentration in seawater leads to ocean acidification. Ocean acidification leading to lowering pH of surface ocean water remains an unsolved problem of science. My today’s lecture will mark an attempt at ...

  12. Red ocean vs blue ocean strategies

    OpenAIRE

    Λαΐνος, Ιάσονας

    2011-01-01

    This paper is about the strategies that a company can adopt in order to get a competitive advantage over its rivals, and thus be successful (Red Ocean Strategies). We also tried to explain what actually entrepreneurship is, to be able to understand why the corporate strategies are formed as they do, and why companies are choosing to follow them. The following project is a part of our master thesis that we will present for the University of Piraeus for the MBA-TQM master department. The thesis...

  13. The oceanic sediment barrier

    International Nuclear Information System (INIS)

    Francis, T.J.G.; Searle, R.C.; Wilson, T.R.S.

    1986-01-01

    Burial within the sediments of the deep ocean floor is one of the options that have been proposed for the disposal of high-level radioactive waste. An international research programme is in progress to determine whether oceanic sediments have the requisite properties for this purpose. After summarizing the salient features of this programme, the paper focuses on the Great Meteor East study area in the Northeast Atlantic, where most oceanographic effort has been concentrated. The geological geochemical and geotechnical properties of the sediments in the area are discussed. Measurements designed to determine the rate of pore water movement through the sediment column are described. Our understanding of the chemistry of both the solid and pore-water phases of the sediment are outlined, emphasizing the control that redox conditions have on the mobility of, for example, naturally occurring manganese and uranium. The burial of instrumented free-fall penetrators to depths of 30 m beneath the ocean floor is described, modelling one of the methods by which waste might be emplaced. Finally, the nature of this oceanic environment is compared with geological environments on land and attention is drawn to the gaps in our knowledge that must be filled before oceanic burial can be regarded as an acceptable disposal option. (author)

  14. The ocean planet.

    Science.gov (United States)

    Hinrichsen, D

    1998-01-01

    The Blue Planet is 70% water, and all but 3% of it is salt water. Life on earth first evolved in the primordial soup of ancient seas, and though today's seas provide 99% of all living space on the planet, little is known about the world's oceans. However, the fact that the greatest threats to the integrity of our oceans come from land-based activities is becoming clear. Humankind is in the process of annihilating the coastal and ocean ecosystems and the wealth of biodiversity they harbor. Mounting population and development pressures have taken a grim toll on coastal and ocean resources. The trend arising from such growth is the chronic overexploitation of marine resources, whereby rapidly expanding coastal populations and the growth of cities have contributed to a rising tide of pollution in nearly all of the world's seas. This crisis is made worse by government inaction and a frustrating inability to enforce existing coastal and ocean management regulations. Such inability is mainly because concerned areas contain so many different types of regulations and involve so many levels of government, that rational planning and coordination of efforts are rendered impossible. Concerted efforts are needed by national governments and the international community to start preserving the ultimate source of all life on earth.

  15. Raft-like membrane domains in pathogenic microorganisms.

    Science.gov (United States)

    Farnoud, Amir M; Toledo, Alvaro M; Konopka, James B; Del Poeta, Maurizio; London, Erwin

    2015-01-01

    The lipid bilayer of the plasma membrane is thought to be compartmentalized by the presence of lipid-protein microdomains. In eukaryotic cells, microdomains composed of sterols and sphingolipids, commonly known as lipid rafts, are believed to exist, and reports on the presence of sterol- or protein-mediated microdomains in bacterial cell membranes are also appearing. Despite increasing attention, little is known about microdomains in the plasma membrane of pathogenic microorganisms. This review attempts to provide an overview of the current state of knowledge of lipid rafts in pathogenic fungi and bacteria. The current literature on characterization of microdomains in pathogens is reviewed, and their potential role in growth, pathogenesis, and drug resistance is discussed. Better insight into the structure and function of membrane microdomains in pathogenic microorganisms might lead to a better understanding of their pathogenesis and development of raft-mediated approaches for therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Experimental studies of biodegradation of asphalt by microorganisms

    International Nuclear Information System (INIS)

    Mine, Tatsuya; Mihara, Morihiro; Ooi, Takao; Lin, Kong-hua; Kawakami, Yasushi

    2000-04-01

    On the geological disposal system of the radioactive wastes, the activities of the microorganisms that could degrade the asphalt might be significant for the assessment of the system performance. As the main effects of the biodegradation of the asphalt, the fluctuation of leaching behavior of the nuclides included in asphalt waste has been indicated. In this study, the asphalt biodegradation test was carried out. The microorganism of which asphalt degradation ability was comparatively higher under aerobic condition and anaerobic condition was used. The asphalt biodegradation rate was calculated and it was evaluated whether the asphalt biodegradation in this system could occur. The results show that the asphalt biodegradation rate under anaerobic and high alkali condition will be 300 times lower than under aerobic and neutral pH. (author)

  17. Synthesis of biosurfactants and their advantages to microorganisms and mankind.

    Science.gov (United States)

    Cameotra, Swaranjit Singh; Makkar, Randhir S; Kaur, Jasminder; Mehta, S K

    2010-01-01

    Biosurfactants are surface-active compounds synthesized by a wide variety of microorganisms. They are molecules that have both hydrophobic and hydrophilic domains and are capable of lowering the surface tension and the interfacial tension of the growth medium. Biosurfactants possess different chemical structures--lipopeptides, glycolipids, neutral lipids and fatty acids. They are nontoxic biomolecules that are biodegradable. Biosurfactants also exhibit strong emulsification of hydrophobic compounds and form stable emulsions. The low water solubility of these hydrophobic compounds limits their availability to microorganisms, which is a potential problem for bioremediation of contaminated sites. Microbially produced surfactants enhance the bioavailability of these hydrophobic compounds for bioremediation. Therefore, biosurfactant-enhanced solubility of pollutants has potential applications in bioremediation. Not only are the biosurfactants useful in a variety of industrial processes, they are also of vital importance to the microbes in adhesion, emulsification, bioavailability, desorption and defense strategy. These interesting facts are discussed in this chapter.

  18. Electrode Cultivation and Interfacial Electron Transport in Subsurface Microorganisms

    Science.gov (United States)

    Karbelkar, A. A.; Jangir, Y.; Reese, B. K.; Wanger, G.; Anderson, C.; El-Naggar, M.; Amend, J.

    2016-12-01

    Continental subsurface environments can present significant energetic challenges to the resident microorganisms. While these environments are geologically diverse, potentially allowing energy harvesting by microorganisms that catalyze redox reactions, many of the abundant electron donors and acceptors are insoluble and therefore not directly bioavailable. Microbes can use extracellular electron transfer (EET) as a metabolic strategy to interact with redox active surfaces. This process can be mimicked on electrode surfaces and hence can lead to enrichment and quantification of subsurface microorganisms A primary bioelectrochemical enrichment with different oxidizing and reducing potentials set up in a single bioreactor was applied in situ to subsurface microorganisms residing in iron oxide rich deposits in the Sanford Underground Research Facility. Secondary enrichment revealed a plethora of classified and unclassified subsurface microbiota on both oxidizing and reducing potentials. From this enrichment, we have isolated a Gram-positive Bacillus along with Gram-negative Cupriavidus and Anaerospora strains (as electrode reducers) and Comamonas (as an electrode oxidizer). The Bacillus and Comamonas isolates were subjected to a detailed electrochemical characterization in half-reactors at anodic and cathodic potentials, respectively. An increase in cathodic current upon inoculation and cyclic voltammetry measurements confirm the hypothesis that Comamonas is capable of electron uptake from electrodes. In addition, measurements of Bacillus on anodes hint towards novel mechanisms that allow EET from Gram-positive bacteria. This study suggests that electrochemical approaches are well positioned to dissect such extracellular interactions that may be prevalent in the subsurface, while using physical electrodes to emulate the microhabitats, redox and geochemical gradients, and the spatially dependent interspecies interactions encountered in the subsurface. Electrochemical

  19. The complexity of wine: clarifying the role of microorganisms.

    Science.gov (United States)

    Tempère, Sophie; Marchal, Axel; Barbe, Jean-Christophe; Bely, Marina; Masneuf-Pomarede, Isabelle; Marullo, Philippe; Albertin, Warren

    2018-05-01

    The concept of wine complexity has gained considerable interest in recent years, both for wine consumers and wine scientists. As a consequence, some research programs concentrate on the factors that could improve the perceived complexity of a wine. Notably, the possible influence of microbiological factors is particularly investigated. However, wine complexity is a multicomponent concept not easily defined. In this review, we first describe the actual knowledge regarding wine complexity, its perception, and wine chemical composition. In particular, we emphasize that, contrary to expectations, the perception of wine complexity is not related to wine chemical complexity. Then, we review the impact of wine microorganisms on wine complexity, with a specific focus on publications including sensory analyses. While microorganisms definitively can impact wine complexity, the underlying mechanisms and molecules are far from being deciphered. Finally, we discuss some prospective research fields that will help improving our understanding of wine complexity, including perceptive interactions, microbial interactions, and other challenging phenomena.

  20. Impacts of Triclosan in Grey water on Soil Microorganisms

    International Nuclear Information System (INIS)

    Harrow, D.I; Felker, J.M; Baker, K.H

    2011-01-01

    The use of grey water for irrigation is becoming a common practice in arid regions such as the Southwestern US, the Middle East, Australia, and China. While grey water supplies nutrients to soil ecosystems, the possible impact of trace contaminants, particularly pharmaceuticals and personal care products, has not been determined. This paper examined the impact of triclosan, an antibacterial agent commonly added to consumer products, on microbial populations and microbial diversity in soil irrigated with grey water. While there was no change in the total number of heterotrophic microorganisms in the soil, both the types and the antibiotic resistance of the microorganisms were significantly influenced by triclosan. The proportion of the microbial isolates resistant to antibiotics increased while at the same time, overall diversity of the microbial community decreased.

  1. Role and functions of beneficial microorganisms in sustainable aquaculture.

    Science.gov (United States)

    Zhou, Qunlan; Li, Kangmin; Jun, Xie; Bo, Liu

    2009-08-01

    This paper aims to review the development of scientific concepts of microecology and ecology of microbes and the role and functions of beneficial microorganisms in aquaculture and mariculture. Beneficial microorganisms play a great role in natural and man-made aquatic ecosystems based on the co-evolution theory in living biosphere on earth. Their functions are to adjust algal population in water bodies so as to avoid unwanted algal bloom; to speed up decomposition of organic matter and to reduce CODmn, NH3-N and NO2-N in water and sediments so as to improve water quality; to suppress fish/shrimp diseases and water-borne pathogens; to enhance immune system of cultured aquatic animals and to produce bioactive compounds such as vitamins, hormones and enzymes that stimulate growth, thus to decrease the FCR of feed.

  2. Ecological aspects of microorganisms inhabiting uranium mill tailings

    Science.gov (United States)

    Miller, C.L.; Landa, E.R.; Updegraff, D.M.

    1987-01-01

    Numbers and types of microorganisms in uranium mill tailings were determined using culturing techniques. Arthrobacter were found to be the predominant microorganism inhabiting the sandy tailings, whereas Bacillus and fungi predominated in the slime tailings. Sulfate-reducing bacteria, capable of leaching radium, were isolated in low numbers from tailings samples but were isolated in significantly high numbers from topsoil in contact with the tailings. The results are placed in the context of the magnitude of uranium mill tailings in the United States, the hazards posed by the tailings, and how such hazards could be enhanced or diminished by microbial activities. Patterns in the composition of the microbial population are evaluated with respect to the ecological variables that influence microbial growth. ?? 1987 Springer-Verlag New York Inc.

  3. Food environments select microorganisms based on selfish energetic behavior

    Directory of Open Access Journals (Sweden)

    Diego eMora

    2013-11-01

    Full Text Available Nutrient richness, and specifically the abundance of mono- and disaccharides that characterize several food matrixes, such as milk and grape juice, has allowed the speciation of lactic acid bacteria and yeasts with a high fermentation capacity instead of energetically favorable respiratory metabolism. In these environmental contexts, rapid sugar consumption and lactic acid or ethanol production, accumulation and tolerance, together with the ability to propagate in the absence of oxygen, are several of the ‘winning’ traits that have apparently evolved and become specialized to perfection in these fermenting microorganisms. Here, we summarize and discuss the evolutionary context that has driven energetic metabolism in food-associated microorganisms, using the dairy species Lactococcus lactis and Streptococcus thermophilus among prokaryotes and the bakers’ yeast Saccharomyces cerevisiae among eukaryotes as model organisms.

  4. The plastic-associated microorganisms of the North Pacific Gyre.

    Science.gov (United States)

    Carson, Henry S; Nerheim, Magnus S; Carroll, Katherine A; Eriksen, Marcus

    2013-10-15

    Microorganisms likely mediate processes affecting the fate and impacts of marine plastic pollution, including degradation, chemical adsorption, and colonization or ingestion by macroorganisms. We investigated the relationship between plastic-associated microorganism communities and factors such as location, temperature, salinity, plankton abundance, plastic concentration, item size, surface roughness, and polymer type. Small plastic items from the surface of the North Pacific Gyre in 2011 were examined using scanning electron microscopy. Bacillus bacteria (mean 1664 ± 247 individuals mm(-2)) and pennate diatoms (1097 ± 154 mm(-2)) were most abundant, with coccoid bacteria, centric diatoms, dinoflagellates, coccolithophores, and radiolarians present. Bacterial abundance was patchy, but increased on foamed polystyrene. Diatom abundance increased on items with rough surfaces and at sites with high plastic concentrations. Morphotype richness increased slightly on larger fragments, and a biogeographic transition occurred between pennate diatom groups. Better characterizing this community will aid in understanding how it interacts with plastic pollution. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Microorganism and filamentous fungi drive evolution of plant synapses.

    Science.gov (United States)

    Baluška, František; Mancuso, Stefano

    2013-01-01

    In the course of plant evolution, there is an obvious trend toward an increased complexity of plant bodies, as well as an increased sophistication of plant behavior and communication. Phenotypic plasticity of plants is based on the polar auxin transport machinery that is directly linked with plant sensory systems impinging on plant behavior and adaptive responses. Similar to the emergence and evolution of eukaryotic cells, evolution of land plants was also shaped and driven by infective and symbiotic microorganisms. These microorganisms are the driving force behind the evolution of plant synapses and other neuronal aspects of higher plants; this is especially pronounced in the root apices. Plant synapses allow synaptic cell-cell communication and coordination in plants, as well as sensory-motor integration in root apices searching for water and mineral nutrition. These neuronal aspects of higher plants are closely linked with their unique ability to adapt to environmental changes.

  6. Metabolic Engineering of Microorganisms for the Production of Higher Alcohols

    Science.gov (United States)

    Choi, Yong Jun; Lee, Joungmin; Jang, Yu-Sin

    2014-01-01

    ABSTRACT Due to the increasing concerns about limited fossil resources and environmental problems, there has been much interest in developing biofuels from renewable biomass. Ethanol is currently used as a major biofuel, as it can be easily produced by existing fermentation technology, but it is not the best biofuel due to its low energy density, high vapor pressure, hygroscopy, and incompatibility with current infrastructure. Higher alcohols, including 1-propanol, 1-butanol, isobutanol, 2-methyl-1-butanol, and 3-methyl-1-butanol, which possess fuel properties more similar to those of petroleum-based fuel, have attracted particular interest as alternatives to ethanol. Since microorganisms isolated from nature do not allow production of these alcohols at high enough efficiencies, metabolic engineering has been employed to enhance their production. Here, we review recent advances in metabolic engineering of microorganisms for the production of higher alcohols. PMID:25182323

  7. Biosynthesis of Nanoparticles by Microorganisms and Their Applications

    Directory of Open Access Journals (Sweden)

    Xiangqian Li

    2011-01-01

    Full Text Available The development of eco-friendly technologies in material synthesis is of considerable importance to expand their biological applications. Nowadays, a variety of inorganic nanoparticles with well-defined chemical composition, size, and morphology have been synthesized by using different microorganisms, and their applications in many cutting-edge technological areas have been explored. This paper highlights the recent developments of the biosynthesis of inorganic nanoparticles including metallic nanoparticles, oxide nanoparticles, sulfide nanoparticles, and other typical nanoparticles. Different formation mechanisms of these nanoparticles will be discussed as well. The conditions to control the size/shape and stability of particles are summarized. The applications of these biosynthesized nanoparticles in a wide spectrum of potential areas are presented including targeted drug delivery, cancer treatment, gene therapy and DNA analysis, antibacterial agents, biosensors, enhancing reaction rates, separation science, and magnetic resonance imaging (MRI. The current limitations and future prospects for the synthesis of inorganic nanoparticles by microorganisms are discussed.

  8. Cell surface hydrophobicity of dental plaque microorganisms in situ.

    OpenAIRE

    Rosenberg, M; Judes, H; Weiss, E

    1983-01-01

    The cell surface hydrophobicity of bacteria obtained directly from human tooth surfaces was assayed by measuring their adherence to liquid hydrocarbons. Fresh samples of supragingival dental plaque were washed and dispersed in buffer. Adherence of the plaque microorganisms to hexadecane, octane, and xylene was tested turbidimetrically and by direct microscopic observation. The results clearly show that the vast majority of bacteria comprising dental plaque exhibit pronounced cell surface hydr...

  9. Activation of inoculum microorganism from dairy cattle feces

    Science.gov (United States)

    Ayuningtyas, Widya D.; Ridwan, Roni; Joni, I. M.; Marlina, E. T.; Harlia, Ellin

    2018-02-01

    Coal produces Coal Bed Methane (CBM) which is formed both biogenically and thermogenically. Lignite is not utilized optimally because it has low heat content and productivity time limit that decreases CBM production. In order to utilize lignite waste, adding inoculum consortium microorganism from dairy cattle waste as starter for biogas process can be a solution. This study aimed to produce inoculum consortium microorganism as biogas starter from dairy cattle feces through in vitro activation process by Theoudorou modification method. The research used complete randomized design with 3 replications. The treatments were blank (R0), 100% concentrate (R1), 70% concentrate+30% grass (R2), 70% grass+30% concentrate (R3) and 100% grass (R4). All treatments were added by buffer solution and feces with ratio of 2:1 into 100 ml serum injection bottle with anaerobic conditions. The parameters observed were gas production, pH and gas kinetics (orskov's equation) for 2, 4, 6, 8, 10, 12, 24 and 48 hours. The results showed that the treatment had significant effect (P <0.05) on the observed parameters. The highest total gas production was for R2 and R3 treatments with total production of 91.17 ml and 101.17 ml, pH (6.62 and 6.57), maximum gas production (94.03 and 97.62 ml), speed of gas production (0.066 and 0.084 ml/hour). There is not a significant difference for both the treatments. The source of inoculum consortium microorganisms for biogas starter selected based on the observed parameters and potential availability of proteolytic and fibrocytic microorganisms is R2 (70% concentrate +30% grass).

  10. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia

    OpenAIRE

    Avellaneda-Torres,Lizeth Manuela; Pulido,Claudia Patricia Guevara; Rojas,Esperanza Torres

    2014-01-01

    A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP), Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as ...

  11. Isolation of Electrogenic Microorganisms with Potential to Reduce Hexavalent Chromium

    Directory of Open Access Journals (Sweden)

    Alexander Mora Collazos

    2017-01-01

    Full Text Available Isolation of cultivable microorganisms was made from the biofilm formed on the anode of a microbial fuel cell put into operation for 30 days; isolated microorganisms were evaluated for their ability to produce energy and reduce the hexavalent chromium Cr (VI. Five microorganisms were isolated, which were characterized by analysis of 16S rRNA gene, placing them in four bacterial genera: Exiguobacterium (CrMFC1, Acinetobacter (CrMFC2, Aeromonas (CrMFC3 and CrMFC5 and Serratia (CrMFC4. All isolates showed electrogenic activity and ability to reduce hexavalent chromium; the Acinetobacter CrMFC1 strain showed the best electrochemical performance registering a maximum power density of 18.61 mW/m2; the other strains showed values of maximum power density between 4.6 mW/m2and 7.1 mW/m2. Strains Aeromonas CrMFC5 and Exiguobacterium CrMFC1 showed the best rates of chromium reduction being able to reduce 100 % of the Cr (VI in less than 24 hours, the Aeromonas CrMFC5 strain was the most efficient, reducing 100 % of Cr (VI in 10 hours; the other strains reduced 100% of the contaminant after 28 to 30 hours. The microorganisms isolated in this study are hardly known for their electrogenic capacity and for reducing Cr (VI; however, show promise for their use in combined systems involving energy production system coupled to bioremediation of chromium contaminated water.

  12. Screening and characterization of useful microorganisms to arsenic removal

    OpenAIRE

    宮武, 宗利; 林, 幸男

    2007-01-01

    Microorganisms were isolated from soil and their arsenic removal abilities were evaluated. Seven out of the 100 isolated strains showed more than 20% arsenic removal. Time courses of arsenic removal and cell growth were investigated in three of these isolated strains. Although the growth rates were different, the dependence of arsenic removal on cell growth was similar in three strains (A-84, 88, 89). Strain A-89 showed highest arsenic removal rate of 63% after first day. Strain A-88 was best...

  13. Uptake of nourseothricin by the producing microorganism, Streptomyces noursei

    International Nuclear Information System (INIS)

    Roeder, B.; Graefe, U.

    1985-01-01

    The uptake of 14 C-(U)-nourseothricin by stationary phase mycelium of Streptomyces noursei JA 3890b-NG 13/14 was demonstrated. An energy-dependent transport system appears to be involved in the transport of the antibiotic. Relatively large quantities of the antibiotic were adsorbed to the surface of mycelium. Degradation of nourseothricin by the producing microorganism was not detectable. (author)

  14. The effect of adhesion on survival and growth of microorganisms

    International Nuclear Information System (INIS)

    Bar-Or, Y.

    1990-01-01

    Adhesion of microorganisms to solid surfaces or water/air interfaces can significantly influence cellular metabolic activity, development and viability. Attachment is of advantage particularly for organisms growing under oligotrophic or otherwise extreme conditions. However, the ability to detach and migrate is of vital importance when prevailing conditions become too harsh or in situations of population explosion. Adhesion can cause alterations in the physical and chemical properties of substratum surfaces as well, by means of degradation, aggregation, emulsification etc. (author) 48 refs

  15. Does nanobiotechnology create new tools to combat microorganisms?

    DEFF Research Database (Denmark)

    Zielinska-Górska, Marlena K.; Sawosz, Ewa; Górski, Konrad

    2017-01-01

    Antimicrobial resistance is still a crucial global problem related to the overuse of antibiotics and natural microorganism capability for rapid horizontal evolution. Even new generations of drugs are not able to overcome bacterial defence mechanisms. A novel solution for this immense medical...... challenge can be nanomaterials. Researchers indicate that modern nanoforms can effectively support and perhaps in the long-term replace traditional bactericidal agents. Because of their unique physicochemical properties, nanotechnology products can exert multiple actions against bacteria, which might...

  16. Using natural biomass microorganisms for drinking water denitrification.

    Science.gov (United States)

    Costa, Darleila Damasceno; Gomes, Anderson Albino; Fernandes, Mylena; Lopes da Costa Bortoluzzi, Roseli; Magalhães, Maria de Lourdes Borba; Skoronski, Everton

    2018-07-01

    Among the methods that are studied to eliminate nitrate from drinking water, biological denitrification is an attractive strategy. Although several studies report the use of denitrifying bacteria for nitrate removal, they usually involve the use of sewage sludge as biomass to obtain the microbiota. In the present study, denitrifying bacteria was isolated from bamboo, and variable parameters were controlled focusing on optimal bacterial performance followed by physicochemical analysis of water adequacy. In this way, bamboo was used as a source of denitrifying microorganisms, using either Immobilized Microorganisms (IM) or Suspended Microorganisms (SM) for nitrate removal. Denitrification parameters optimization was carried out by analysis of denitrification at different pH values, temperature, nitrate concentrations, carbon sources as well as different C/N ratios. In addition, operational stability and denitrification kinetics were evaluated. Microorganisms present in the biomass responsible for denitrification were identified as Proteus mirabilis. The denitrified water was submitted to physicochemical treatment such as coagulation and flocculation to adjust to the parameters of color and turbidity to drinking water standards. Denitrification using IM occurred with 73% efficiency in the absence of an external carbon source. The use of SM provided superior denitrification efficiency using ethanol (96.46%), glucose (98.58%) or glycerol (98.5%) as carbon source. The evaluation of the operational stability allowed 12 cycles of biomass reuse using the IM and 9 cycles using the SM. After physical-chemical treatment, only SM denitrified water remained within drinking water standards parameters of color and turbidity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Generation of PHB from Spent Sulfite Liquor Using Halophilic Microorganisms.

    Science.gov (United States)

    Weissgram, Michaela; Gstöttner, Janina; Lorantfy, Bettina; Tenhaken, Raimund; Herwig, Christoph; Weber, Hedda K

    2015-06-08

    Halophilic microorganisms thrive at elevated concentrations of sodium chloride up to saturation and are capable of growing on a wide variety of carbon sources like various organic acids, hexose and also pentose sugars. Hence, the biotechnological application of these microorganisms can cover many aspects, such as the treatment of hypersaline waste streams of different origin. Due to the fact that the high osmotic pressure of hypersaline environments reduces the risk of contamination, the capacity for cost-effective non-sterile cultivation can make extreme halophilic microorganisms potentially valuable organisms for biotechnological applications. In this contribution, the stepwise use of screening approaches, employing design of experiment (DoE) on model media and subsequently using industrial waste as substrate have been implemented to investigate the applicability of halophiles to generate PHB from the industrial waste stream spent sulfite liquor (SSL). The production of PHB on model media as well as dilutions of industrial substrate in a complex medium has been screened for by fluorescence microscopy using Nile Blue staining. Screening was used to investigate the ability of halophilic microorganisms to withstand the inhibiting substances of the waste stream without negatively affecting PHB production. It could be shown that neither single inhibiting substances nor a mixture thereof inhibited growth in the investigated range, hence, leaving the question on the inhibiting mechanisms open. However, it could be demonstrated that some haloarchaea and halophilic bacteria are able to produce PHB when cultivated on 3.3% w/w dry matter spent sulfite liquor, whereas H. halophila was even able to thrive on 6.6% w/w dry matter spent sulfite liquor and still produce PHB.

  18. Biotransformation of citrus aromatics nootkatone and valencene by microorganisms.

    Science.gov (United States)

    Furusawa, Mai; Hashimoto, Toshihiro; Noma, Yoshiaki; Asakawa, Yoshinori

    2005-11-01

    Biotransformations of the sesquiterpene ketone nootkatone from the crude drug Alpiniae Fructus and grapefruit oil, and the sesquiterpene hydrocarbon valencene from Valencia orange oil were carried out with microorganisms such as Aspergillus niger, Botryosphaeria dothidea, and Fusarium culmorum to afford structurally interesting metabolites. Their stereostructures were established by a combination of high-resolution NMR spectral and X-ray crystallographic analysis and chemical reaction. Metabolic pathways of compounds and by A. niger are proposed.

  19. Coal Enrichment Methods by Using Microorganisms and Their Metabolites

    Directory of Open Access Journals (Sweden)

    Małgorzata Deska

    2018-03-01

    Full Text Available The aim of this study is to review the literature on the methods of low-rank coal enrichment by using microorganisms and their metabolites. Effective bio-beneficiation technologies for low-rank coals in the future are also suggested throughout this paper. An extensive literature review highlights recent advances in bio-beneficiation technologies for low rank coals. This paper presents the state of the art in the field of the bio-beneficiation technology - carbon leaching with the aid of microorganisms, especially fungi. The knowledge of the low-rank coals leaching is an important step to meet the carbon eco-requirements and improve the economics of mining companies. There are several reasons to investigate microbial activities towards coal. This paper presents the current state of knowledge concerning bioleaching of coal. Thus, in view of the increasing importance of hard coal as a raw material and energy source, it seems hopeful to study the potential of microorganisms to modify the low-rank coal structure.

  20. Detection of extracellular proteases from microorganisms on agar plates

    Directory of Open Access Journals (Sweden)

    Alane Beatriz Vermelho

    1996-12-01

    Full Text Available We present herein an improved assay for detecting the presence of extracellular proteases from microorganisms on agar plates. Using different substrates (gelatin, BSA, hemoglobin incorporated into the agar and varying the culture medium composition, we were able to detect proteolytic activities from Pseudomonas aeruginosa, Micrococcus luteus and Serratia marcescens as well as the influence that these components displayed in the expression of these enzymes. For all microorganisms tested we found that in agar-BHI or yeast extract medium containing gelatin the sensitivity of proteinase detection was considerably greater than in BSA-agar or hemoglobin-agar. However, when BSA or hemoglobin were added to the culture medium, there was an increase in growth along with a marked reduction in the amount of proteinase production. In the case of M. luteus the incorporation of glycerol in BHI or yeast extract gelatin-agar induced protease liberation. Our results indicate that the technique described here is of value for detecting extracellular proteases directly in the culture medium, by means of a qualitative assay, simple, inexpensive, straight forward method to assess the presence of the proteolytic activity of a given microorganism colony with great freedom in substrate selection.

  1. MICROORGANISMS IN SELECTED CONFECTIONARY PRODUCTS DURING THE MANUFACTURING PROCESS

    Directory of Open Access Journals (Sweden)

    Jana Petrová

    2015-02-01

    Full Text Available The aim of our study was to evaluate the microbiological quality confectionery products during production. A total of 135 samples were analyzed: 45 samples of the punch balls, 45 Venček samples and 45 samples French cubes from home, school and private production. For microorganism cultivation VRBL agar for the isolation of coliform bacteria, DRBC and DG18 for microscopic fungi and yeasts, Plate Count Agar for total viable count, Meat peptone agar for mesophilic aerobic bacteria, XLD agar for Salmonella sp. and Baird Parker agar for Staphylococcus aureus were used. Following microbiological parameters were tested: total viable count, mesophilic anaerobic microorganisms, coliform bacteria, yeast and microscopic filamentous fungi, Salmonella spp. and Staphylococcus aureus. Products are assessed according to the limit values of the number of microorganisms contained in the Codex Alimentary of the Slovak Republic. The overall assessment of the microbiological quality of the punch balls, we found that two samples from school factory and one sample from private producer did not meet CA SR for the total viable count. Comparing the microbiological quality of Venček with CA SR, we found that one sample of home production did not meet the requirements for this type of product. All the tested samples were Staphylococcus aureus and Salmonella spp. negative. Comparing the results of the samples with French cubes CA SR, we found that all the samples satisfy requirements.

  2. Periodontopathic microorganisms in peripheric blood after scaling and root planing.

    Science.gov (United States)

    Lafaurie, Gloria Inés; Mayorga-Fayad, Isabel; Torres, María Fernanda; Castillo, Diana Marcela; Aya, Maria Rosario; Barón, Alexandra; Hurtado, Paola Andrea

    2007-10-01

    The objective of this study was to evaluate the frequency of periodontopathic and other subgingival anaerobic and facultative bacteria in the bloodstream following scaling and root planing (SRP). Forty-two patients with severe generalized chronic periodontitis (GChP) and generalized aggressive periodontitis (GAgP) were included in the study. Four samples of peripheric blood were drawn from the cubital vein at different times: Pre-treatment: immediately before the SRP procedure (T1), immediately after treatment (T2), 15 min. post-treatment (T3) and 30 min. post-treatment (T4). In order to identify the presence of microorganisms in blood, subcultures were conducted under anaerobic conditions. 80.9% of the patients presented positive cultures after SRP and it occurred more frequently immediately after treatment; however, 19% of the patients still had microorganisms in the bloodstream 30 min. after the procedure. The periodontopathic microorganisms more frequently identified were Porphyromonas gingivalis and Micromonas micros. Campylobacter spp., Eikenella corrodens, Tannerella forsythensis, Fusobacterium spp. and Prevotella intermedia were isolated less often. Actinomyces spp. were also found frequently during bacteraemia after SRP. SRP induced bacteraemia associated with anaerobic bacteria, especially in patients with periodontal disease.

  3. Selection of potential microorganism for sago starch fermentation

    Directory of Open Access Journals (Sweden)

    RUTH MELLIAWATI

    2006-02-01

    Full Text Available Fermentation process of sago starch for the production of bioproduct requires potential microorganism that have ability to hydrolyze sago starch. The purpose of this research was to get the potential of amylolytic microorganisms for their capability of amyloglucosidase activity and to know the sugar strains of the fermentation result. Eleven amylolytic microorganisms (9 strains of mold and 2 strains of yeast were obtained from the collection Research Centre for Biotechnology – Indonesian Institute of Sciences (LIPI, Cibinong-Bogor were used. The selection step was carried out based on their capability of starch hydrolysis to reducing sugar. The best result indicates that the production of reducing sugar reached the highest 18.485 ppm and amyloglucosidase activities was 3.583 units by KTU-1 strain. The highest total acid obtained was 5.85 mg/mL by Rhizopus IFO.R5442. The cell biomass was obtained between 0.5 to 1.74 g dry weight/100 mL and pH of the final fermentation (72 h were 3.57 to 8.38.

  4. The diversity of microorganisms associated with Acromyrmex leafcutter ants

    Directory of Open Access Journals (Sweden)

    Boomsma Jacobus J

    2002-05-01

    Full Text Available Abstract Background Molecular biological techniques are dramatically changing our view of microbial diversity in almost any environment that has so far been investigated. This study presents a systematic survey of the microbial diversity associated with a population of Acromyrmex leafcutter ants. In contrast to previous studies on social insects, which targeted specific groups of symbionts occurring in the gut (termites, Tetraponera ants or in specialised cells (Camponotus ants the objective of our present study was to do a total screening of all possible micro-organisms that can be found inside the bodies of these leafcutter ants. Results We amplified, cloned and sequenced SSU rRNA encoding gene fragments from 9 microbial groups known to have insect-associated representatives, and show that: (1 representatives of 5 out of 9 tested groups are present, (2 mostly several strains per group are present, adding up to a total of 33 different taxa. We present the microbial taxa associated with Acromymex ants in a phylogenetic context (using sequences from GenBank to assess and illustrate to which known microorganisms they are closely related. The observed microbial diversity is discussed in the light of present knowledge on the evolutionary history of Acromyrmex leafcutter ants and their known mutualistic and parasitic symbionts. Conclusions The major merits of the screening approach documented here is its high sensitivity and specificity, which allowed us to identify several microorganisms that are promising candidates for further study of their interactions with Acromyrmex leafcutter ants or their gardens.

  5. Toxicity of fluoride to microorganisms in biological wastewater treatment systems.

    Science.gov (United States)

    Ochoa-Herrera, Valeria; Banihani, Qais; León, Glendy; Khatri, Chandra; Field, James A; Sierra-Alvarez, Reyes

    2009-07-01

    Fluoride is a common contaminant in a variety of industrial wastewaters. Available information on the potential toxicity of fluoride to microorganisms implicated in biological wastewater treatment is very limited. The objective of this study was to evaluate the inhibitory effect of fluoride towards the main microbial populations responsible for the removal of organic constituents and nutrients in wastewater treatment processes. The results of short-term batch bioassays indicated that the toxicity of sodium fluoride varied widely depending on the microbial population. Anaerobic microorganisms involved in various metabolic steps of anaerobic digestion processes were found to be very sensitive to the presence of fluoride. The concentrations of fluoride causing 50% metabolic inhibition (IC(50)) of propionate- and butyrate-degrading microorganisms as well as mesophilic and thermophilic acetate-utilizing methanogens ranged from 18 to 43 mg/L. Fluoride was also inhibitory to nitrification, albeit at relatively high levels (IC(50)=149 mg/L). Nitrifying bacteria appeared to adapt rapidly to fluoride, and a near complete recovery of their metabolic activity was observed after only 4d of exposure to high fluoride levels (up to 500 mg/L). All other microbial populations evaluated in this study, i.e., glucose fermenters, aerobic glucose-degrading heterotrophs, denitrifying bacteria, and H(2)-utilizing methanogens, tolerated fluoride at very high concentrations (>500 mg/L).

  6. Characterization of Microorganisms Isolated from Petroleum Hydrocarbon Polluted Soil

    Directory of Open Access Journals (Sweden)

    Adriana Criste

    2016-02-01

    Full Text Available Bioremediation has received a great deal of attention, and bacteria isolated from polluted soil can be usedin that process. In this study, we performed an evaluation of the physiological groups of microorganisms fromsoil contaminated with petroleum. Bacterial strains were isolated from contaminated soil using the selectiveenrichment technique. Minimal Salt Media was used for serial dilutions to determine viable cell count. Thenumber of total viable cells and different types of microorganisms in the original sample was determined by serialdilution, agar plating procedure using selective media. The plates were incubated at 300C for 24-72 hours. Distinctcolonies growing on each plate were selected, and stored at freezing temperatures. The bacterial colonies werethen identified by Gram staining and biochemical tests. Following our research, it was observed that although thetotal microbial load of soil is relatively close in value, there are differences regarding the physiological group ofmicroorganisms. In the oil contaminated soil sample the largest group of microorganisms was the nitrous nitrifyingbacteria followed by nitrate bacteria. All bacterial strains that were isolated from soil samples contaminated withhydrocarbons but also the Pseudomonas putida and Bacillus subtillis strains can use diesel fuel as a food source.With the increase of diesel fuel concentration from culture medium, the majority of the bacterial strains that wereused in our experiments showed an increased value of absorbance. This fact suggests that these strains can be usedin bioremediation processes.

  7. Antimicrobial activity of jasmine oil against oral microorganisms

    Science.gov (United States)

    Thaweboon, S.; Thaweboon, B.; Kaypetch, R.

    2018-02-01

    Jasmine sambac is a species of jasmine indigenous to the tropical and warm temperature regions in particular West and Southeast Asia. Essential oil extracted from the flowers of J. sambac has been shown to have anti-oxidant activity. However, very little information regarding antimicrobial activity especially oral microorganisms exists. Objective: To investigate antimicrobial effect of essential oil extracted from flowers of J. sambac against various oral microorganisms. Materials and Methods: Oral microbial strains used in the study were Streptococcus mutans KPSK2, Staphylococcus aureus ATCC 5638, Lactobacillus casei ATCC 6363, Klebsiella pneumoniae (clinical isolate), Escherichia coli ATCC 25922, Candida albicans ATCC 10231, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida tropicalis (clinical isolate), Candida glabrata ATCC 90030, Candida pseudotropicalis (clinical isolate) and Candida stellatoidia (clinical isolate). The potential of microbial growth inhibition of the oil was firstly screened by Kirby-Bauer disk diffusion method and then the minimum inhibitory concentration (MIC) was determined by agar dilution method. Results: Jasmine oil showed antimicrobial activities against S. mutans, L. casei, E. coli and all strains of Candida species with the zones of inhibition ranging from 9 to 26 mm and MIC values of 0.19-1.56 %v/v. Conclusion: Results from the present study are scientific evidence to demonstrate that jasmine oil could be employed as a natural antimicrobial agent against oral microorganisms.

  8. Antimicrobial activity of different disinfectants against cariogenic microorganisms

    Directory of Open Access Journals (Sweden)

    Esra UZER CELIK

    Full Text Available Abstract The aim of this study was to assess the in vitro antimicrobial effects of chlorhexidine digluconate (CHX, polyhexamethylene biguanide (PHBM, and octenidine dihydrochloride (OCT on cariogenic microorganisms by using their minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC. CHX, PHBM, and OCT were diluted in distilled water to the final test concentrations. Using the in-tube dilution method, Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Actinomyces viscosus were cultivated on blood agar and Mueller–Hinton broth (MHB at 37°C for 48 h. They were read using a spectrophotometer to detect MIC. To determine MBC, samples in the range of the turbidity threshold after 24 h were transferred onto blood agar and evaluated for growth after 24 h. Different MICs and MBCs were observed in all disinfectants against each microorganism. The lowest MIC and MBC against S. mutans (60 mg/L were obtained from PHBM. The lowest values against L. rhamnosus (15 mg/L, 30 mg/L, A. viscosus (30 mg/L, and L. acidophilus (15 mg/L, 30 mg/L were determined by OCT. PHBM and OCT have the potential to be replaced with CHX because they were effective against cariogenic microorganisms.

  9. Growth response of microorganisms to different molecular fractions of lignite

    Energy Technology Data Exchange (ETDEWEB)

    Polman, J.K.; Breckenridge, C.R.; Dugan, P.R.; Quigley, D.R.

    1990-01-01

    Our research is primarily concerned with isolating and characterizing microbes which are able to dissimilate coal and convert it to other useful chemicals. This quarter, general growth responses of microorganisms cultivated in the presence of different molecular weight fractions of lignite coal were examined. Aerobic and anaerobic environmental samples from a variety of ecological niches were used as inocula. Growth of the microorganisms in these samples on the following types of media was tested: COAL medium, containing alkali-solubilized whole coal; THFI medium, containing the alkali-solubilized, tetrahydrofuran-insoluble, macromolecular portion of whole coal; THFS medium, containing the THF-soluble, low molecular weight portion of whole coal; and CON medium, void of any coal constituent. Overall results indicated that the presence of the THF-soluble, low molecular weight coal fraction enhanced the growth yield and the variety of aerobic microorganisms compared to the other coal fractions or the control medium. Conversely, anaerobic microbes grew best on media which contained the macromolecular fraction. 12 refs., 5 tabs.

  10. Preparation of microorganism free carrier for biofertilizer product

    International Nuclear Information System (INIS)

    Latiffah Norddin; Maizatul Akmam Mhd Nasir; Phua Choo Kwai Hoe

    2007-01-01

    Biofertilizer has been identified as an alternative or complementary to chemical fertilizer to increase soil fertility and crop production in sustainable farming. Biofertilizers are products containing living cells of different types of known microorganisms that may increase crop productivity through N2 fixation, phosphate solubilization or stimulation of plant growth by synthesising phytohormones. A good biofertilizer product needs a good carrier or substrate. A good carrier is free from microbial contamination and can optimise the growth of the biofertilizer microorganisms. Compost is commonly used as carrier or substrate for biofertilizer microorganisms. In the present study, compost produced by Nuclear Malaysia using the Natural Farming was used as a carrier for the biofertilizer products. Gamma irradiation has been used to produce a ?clean? or sterile carrier. The sterilization effect of the carrier was checked by using serial dilution technique. Carriers that were irradiated at 50 kGy of gamma irradiation were found to be sterile. The shelf life of the sterile carriers was also determined. After six months the compost carriers were still free from microbial contamination. (Author)

  11. Microorganisms as potential vectors of the migration of radionuclides?

    International Nuclear Information System (INIS)

    Yves, A.

    1998-01-01

    The aims of our work are the study of the sorption of radionuclides by bacteria as the first step in the microorganism-metal interaction. The latter involves the fixation of ions on a surface layer and it results in the immobilization of the metal, thus possibly being the primary step of bioaccumulation. After a rapid presentation of the direct and indirect mechanisms of the interactions, we shall present our experiments of radionuclide biosorption by bacteria. A salient feature of biosorption is the selectivity of the adsorption of some radionuclides from a composed solution. For example, Andres et al. (1993, 1995) have shown that Mycobacterium smegmatis, from a composed solution containing uranium, thorium, lanthanum, europium and ytterbium, selectively adsorbs thorium ions. The sequence of preferential fixation is: Th 4+ > UO 2 2+ > La 3+ = Eu 3+ = Yb 3+ . This selectivity is a function of the cell wall organization and of the speciation of the metal in the solution. Yet, each species of bacteria has characteristic and specific cell wall layer composition and organization. Moreover, the culture and the environmental conditions change the surface layer properties. Another parameter in the migration of radionuclides is the transfer from the soil to the microorganisms. In column experiments, Gd, and likely the rare earths, in general, adsorbed on sand can be removed with a suspension of bacteria (Thouand and Andres 1997). These examples will be discussed and serve as a basis to illustrate the diversity of the interactions between microorganisms and radionuclides

  12. Environment purification using microorganisms. Biseibutsu ni yoru kankyo joka

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, H [Asahi Glass Co. Ltd., Tokyo (Japan); Harada, S

    1993-12-01

    Technologies to purify polluted soils vary with kinds of pollutants, spread of pollution, and shapes of water veins. A method is used often that several wells are drilled in a polluted area, and water is circulated between upstream wells and downstream wells, where activities of microorganisms living in that particular environment are utilized to biodegrade the pollutants. This technology is called bioremediation. This paper deals with soil pollution by chemical substances, and describes development of a technology to remove pollution caused by PCB and petroleum which is thought difficult to apply the bioremediation technology among environment purifying technologies using microorganisms. The bioremediation of petroleum pollution assumes petroleum pollution on seashores. Discussions have been given on separation from sea water of petroleum decomposing microorganisms to be used in the bioremediation, and the number of petroleum decomposing bacteria in seas near Japan. As a result, it was made clear that a few kinds of bacteria will suffice for decomposition of main components in a mixture as complex as petroleum. 5 refs., 4 figs.

  13. The plastic-associated microorganisms of the North Pacific Gyre

    International Nuclear Information System (INIS)

    Carson, Henry S.; Nerheim, Magnus S.; Carroll, Katherine A.; Eriksen, Marcus

    2013-01-01

    Highlights: • Microorganisms mediate processes affecting the fate and impacts of marine plastic. • North Pacific Gyre (NPG) plastics were examined with scanning-electron microscopy. • Bacillus bacteria and pennate diatoms dominated the NPG plastic fouling community. • Bacterial abundance was patchily distributed but increased on foamed polystyrene. • Diatom abundance increased on rough surfaces and at sites with high plastic density. -- Abstract: Microorganisms likely mediate processes affecting the fate and impacts of marine plastic pollution, including degradation, chemical adsorption, and colonization or ingestion by macroorganisms. We investigated the relationship between plastic-associated microorganism communities and factors such as location, temperature, salinity, plankton abundance, plastic concentration, item size, surface roughness, and polymer type. Small plastic items from the surface of the North Pacific Gyre in 2011 were examined using scanning electron microscopy. Bacillus bacteria (mean 1664 ± 247 individuals mm −2 ) and pennate diatoms (1097 ± 154 mm −2 ) were most abundant, with coccoid bacteria, centric diatoms, dinoflagellates, coccolithophores, and radiolarians present. Bacterial abundance was patchy, but increased on foamed polystyrene. Diatom abundance increased on items with rough surfaces and at sites with high plastic concentrations. Morphotype richness increased slightly on larger fragments, and a biogeographic transition occurred between pennate diatom groups. Better characterizing this community will aid in understanding how it interacts with plastic pollution

  14. Ocean acoustic tomography

    International Nuclear Information System (INIS)

    Cornuelle, Bruce D; Worcester, Peter F; Dzieciuch, Matthew A

    2008-01-01

    Ocean acoustic tomography (OAT) was proposed in 1979 by Walter Munk and Carl Wunsch as an analogue to x-ray computed axial tomography for the oceans. The oceans are opaque to most electromagnetic radiation, but there is a strong acoustic waveguide, and sound can propagate for 10 Mm and more with distinct multiply-refracted ray paths. Transmitting broadband pulses in the ocean leads to a set of impulsive arrivals at the receiver which characterize the impulse response of the sound channel. The peaks observed at the receiver are assumed to represent the arrival of energy traveling along geometric ray paths. These paths can be distinguished by arrival time, and by arrival angle when a vertical array of receivers is available. Changes in ray arrival time can be used to infer changes in ocean structure. Ray travel time measurements have been a mainstay of long-range acoustic measurements, but the strong sensitivity of ray paths to range-dependent sound speed perturbations makes the ray sampling functions uncertain in real cases. In the ray approximation travel times are sensitive to medium changes only along the corresponding eigenrays. Ray theory is an infinite-frequency approximation, and its eikonal equation has nonlinearities not found in the acoustic wave equation. We build on recent seismology results (kernels for body wave arrivals in the earth) to characterize the kernel for converting sound speed change in the ocean to travel time changes using more complete propagation physics. Wave-theoretic finite frequency kernels may show less sensitivity to small-scale sound speed structure.

  15. In vivo investigations of genetically modified microorganisms using germ-free rats

    DEFF Research Database (Denmark)

    Lund jacobsen, Bodil

    Risk evaluation of genetically modified microorganism (GMMO) in relation to human health effects brings into consideration the ability of the microorganism to survive and colonise the gastrointestinal tract and the potential gene transfer to the resident microbiota. Different biological containment...

  16. 40 CFR 725.67 - Applications to exempt new microorganisms from this part.

    Science.gov (United States)

    2010-07-01

    ...) The effects of the new microorganism on health and the environment. (ii) The magnitude of exposure of human beings and the environment to the new microorganism. (iii) The benefits of the new microorganism... economic consequences of granting or denying the exemption, including effects on the national economy...

  17. DMPD: Signaling pathways activated by microorganisms. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17303405 Signaling pathways activated by microorganisms. Takeuchi O, Akira S. Curr ...Opin Cell Biol. 2007 Apr;19(2):185-91. Epub 2007 Feb 15. (.png) (.svg) (.html) (.csml) Show Signaling pathways activated by microorg...anisms. PubmedID 17303405 Title Signaling pathways activated by microorganisms. Auth

  18. Test and research on the production of useful matter with carbon-dioxide-fixed microorganisms. Production of biodegradation plastics with photosynthesized microorganisms. Tansan gas kotei biseibutsu wo mochiita yuyo busshitsu seisan shiken kenkyu. Kogosei biseibutsu ni yoru seibunkaisei plastic seisan

    Energy Technology Data Exchange (ETDEWEB)

    Miyasaka, H. (The Kansai Electric Power Co. Inc., Osaka (Japan))

    1994-07-10

    The present report introduces the basic research on the production of PHB (one of the biodegradation plastics) by utilizing the photosynthesized microorganisms. The indigo algae are conveniently used for the genetic operation, because they are genetically inferior and have plasmid (extranuclear ringed DNA). Therefore, a certain type of oceanic indigo algae was used for the present research. As a vector to introduce the PHB-producing gene into the indigo alga cell, hybrid plasmid was prepared by combining the indigo alga plasmid pAQ1 with colon bacillus plasmid vectors pUC19. The thus prepared vectors had an introduction efficiency into about 1000 cells per one vector. A RuBisCO gene of indigo alga cell was selected as a promoter to heighten the activity of PHB-producing gene in that cell. The gene is being further studied in promotion efficiency by combining it with the above vector and PHB-producing gene. 4 figs.

  19. Acinetobacter species as model microorganisms in environmental microbiology: current state and perspectives.

    Science.gov (United States)

    Jung, Jaejoon; Park, Woojun

    2015-03-01

    Acinetobacter occupies an important position in nature because of its ubiquitous presence in diverse environments such as soils, fresh water, oceans, sediments, and contaminated sites. Versatile metabolic characteristics allow species of this genus to catabolize a wide range of natural compounds, implying active participation in the nutrient cycle in the ecosystem. On the other hand, multi-drug-resistant Acinetobacter baumannii causing nosocomial infections with high mortality has been raising serious concerns in medicine. Due to the ecological and clinical importance of the genus, Acinetobacter was proposed as a model microorganism for environmental microbiological studies, pathogenicity tests, and industrial production of chemicals. For these reasons, Acinetobacter has attracted significant attention in scientific and biotechnological fields, but only limited research areas such as natural transformation and aromatic compound degradation have been intensively investigated, while important physiological characteristics including quorum sensing, motility, and stress response have been neglected. The aim of this review is to summarize the recent achievements in Acinetobacter research with a special focus on strain DR1 and to compare the similarities and differences between species or other genera. Research areas that require more attention in future research are also suggested.

  20. An Ocean of Possibilities

    Science.gov (United States)

    Williams, Doug

    2010-01-01

    For more than one hundred years teachers have paddled beside the great ocean of mathematical adventure. Between them they have taught millions of young people. A few have dived in and kept swimming, some have lingered on the shore playing in pools, but most have dipped their toes in and run like heck in the other direction never to return. There…

  1. Deep Water Ocean Acoustics

    Science.gov (United States)

    2016-12-22

    roughly 28°S. The second is the Hawaiian Island Chain, extending to Midway Island at 28°N, 177°W and finally the Emperor Seamount chain running due...dimension array centered near Ascension. The climatology ocean (WOA09) showed very little seasonal dependence or change from the geodesic and this is

  2. Enhanced Ocean Scatterometry

    NARCIS (Netherlands)

    Fois, F.

    2015-01-01

    An ocean scatterometer is an active microwave instrument which is designed to determine the normalized radar cross section (NRCS) of the sea surface. Scatterometers transmit pulses towards the sea surface and measure the reflected energy. The primary objective of spaceborne scatterometers is to

  3. Power from Ocean Waves.

    Science.gov (United States)

    Newman, J. N.

    1979-01-01

    Discussed is the utilization of surface ocean waves as a potential source of power. Simple and large-scale wave power devices and conversion systems are described. Alternative utilizations, environmental impacts, and future prospects of this alternative energy source are detailed. (BT)

  4. Investigating Ocean Pollution.

    Science.gov (United States)

    LeBeau, Sue

    1998-01-01

    Describes a fifth-grade class project to investigate two major forms of ocean pollution: plastics and oil. Students work in groups and read, discuss, speculate, offer opinions, and participate in activities such as keeping a plastics journal, testing the biodegradability of plastics, and simulating oil spills. Activities culminate in…

  5. Ocean Dumping Control Act

    International Nuclear Information System (INIS)

    1975-01-01

    This Act provides for the control of dumping of wastes and other substances in the ocean in accordance with the London Convention of 1972 on Prevention of Marine Pollution by the Dumping of Wastes and other Matter to which Canada is a Party. Radioactive wastes are included in the prohibited and restricted substances. (NEA)

  6. Ocean Ridges and Oxygen

    Science.gov (United States)

    Langmuir, C. H.

    2014-12-01

    The history of oxygen and the fluxes and feedbacks that lead to its evolution through time remain poorly constrained. It is not clear whether oxygen has had discrete steady state levels at different times in Earth's history, or whether oxygen evolution is more progressive, with trigger points that lead to discrete changes in markers such as mass independent sulfur isotopes. Whatever this history may have been, ocean ridges play an important and poorly recognized part in the overall mass balance of oxidants and reductants that contribute to electron mass balance and the oxygen budget. One example is the current steady state O2 in the atmosphere. The carbon isotope data suggest that the fraction of carbon has increased in the Phanerozoic, and CO2 outgassing followed by organic matter burial should continually supply more O2 to the surface reservoirs. Why is O2 not then increasing? A traditional answer to this question would relate to variations in the fraction of burial of organic matter, but this fraction appears to have been relatively high throughout the Phanerozoic. Furthermore, subduction of carbon in the 1/5 organic/carbonate proportions would contribute further to an increasingly oxidized surface. What is needed is a flux of oxidized material out of the system. One solution would be a modern oxidized flux to the mantle. The current outgassing flux of CO2 is ~3.4*1012 moles per year. If 20% of that becomes stored organic carbon, that is a flux of .68*1012 moles per year of reduced carbon. The current flux of oxidized iron in subducting ocean crust is ~2*1012 moles per year of O2 equivalents, based on the Fe3+/Fe2+ ratios in old ocean crust compared to fresh basalts at the ridge axis. This flux more than accounts for the incremental oxidizing power produced by modern life. It also suggests a possible feedback through oxygenation of the ocean. A reduced deep ocean would inhibit oxidation of ocean crust, in which case there would be no subduction flux of oxidized

  7. Zoogeography of the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, T.S.S.

    The distribution pattern of zooplankton in the Indian Ocean is briefly reviewed on a within and between ocean patterns and is limited to species within a quite restricted sort of groups namely, Copepoda, Chaetognatha, Pteropoda and Euphausiacea...

  8. World Ocean Atlas 2005, Temperature

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Ocean Atlas 2005 (WOA05) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen...

  9. OW CCMP Ocean Surface Wind

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Cross-Calibrated Multi-Platform (CCMP) Ocean Surface Wind Vector Analyses (Atlas et al., 2011) provide a consistent, gap-free long-term time-series of monthly...

  10. OW ASCAT Ocean Surface Winds

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Advanced Scatterometer (ASCAT) sensor onboard the EUMETSAT MetOp polar-orbiting satellite provides ocean surface wind observations by means of radar...

  11. World Ocean Atlas 2005, Salinity

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Ocean Atlas 2005 (WOA05) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen...

  12. Satellite Ocean Heat Content Suite

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This collection contains an operational Satellite Ocean Heat Content Suite (SOHCS) product generated by NOAA National Environmental Satellite, Data, and Information...

  13. ocean_city_md.grd

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC builds and distributes high-resolution, coastal digital elevation models (DEMs) that integrate ocean bathymetry and land topography to support NOAA's mission to...

  14. A Comprehensive Characterization of Microorganisms and Allergens in Spacecraft Environment

    Science.gov (United States)

    Castro, V.A.; Ott, C.M.; Garcia, V.M.; John, J.; Buttner, M.P.; Cruz, P.; Pierson, D.L.

    2009-01-01

    The determination of risk from infectious disease during long-duration missions is composed of several factors including the concentration and the characteristics of the infectious agent. Thus, a thorough knowledge of the microorganisms aboard spacecraft is essential in mitigating infectious disease risk to the crew. While stringent steps are taken to minimize the transfer of potential pathogens to spacecraft, several medically significant organisms have been isolated from both the Mir and International Space Station (ISS). Historically, the method for isolation and identification of microorganisms from spacecraft environmental samples depended upon their growth on culture media. Unfortunately, only a fraction of the organisms may grow on a culture medium, potentially omitting those microorganisms whose nutritional and physical requirements for growth are not met. Thus, several pathogens may not have been detected, such as Legionella pneumophila, the etiological agent of Legionnaire s disease. We hypothesize that environmental analysis using non-culture-based technologies will reveal microorganisms, allergens, and microbial toxins not previously reported in spacecraft, allowing for a more complete health assessment. The development of techniques for this flight experiment, operationally named SWAB, has already provided advances in NASA laboratory processes and beneficial information toward human health risk assessment. The translation of 16S ribosomal DNA sequencing for the identification of bacteria from the SWAB experiment to nominal operations has increased bacterial speciation of environmental isolates from previous flights three fold compared to previous conventional methodology. The incorporation of molecular-based DNA fingerprinting using repetitive sequence-based polymerase chain reaction (rep-PCR) into the capabilities of the laboratory has provided a methodology to track microorganisms between crewmembers and their environment. Both 16S ribosomal DNA

  15. N2 fixation as a dominant new N source in the western tropical South Pacific Ocean (OUTPACE cruise)

    Science.gov (United States)

    Caffin, Mathieu; Moutin, Thierry; Foster, Rachel Ann; Bouruet-Aubertot, Pascale; Michelangelo Doglioli, Andrea; Berthelot, Hugo; Guieu, Cécile; Grosso, Olivier; Helias-Nunige, Sandra; Leblond, Nathalie; Gimenez, Audrey; Petrenko, Anne Alexandra; de Verneil, Alain; Bonnet, Sophie

    2018-05-01

    We performed nitrogen (N) budgets in the photic layer of three contrasting stations representing different trophic conditions in the western tropical South Pacific (WTSP) Ocean during austral summer conditions (February-March 2015). Using a Lagrangian strategy, we sampled the same water mass for the entire duration of each long-duration (5 days) station, allowing us to consider only vertical exchanges for the budgets. We quantified all major vertical N fluxes both entering (N2 fixation, nitrate turbulent diffusion, atmospheric deposition) and leaving the photic layer (particulate N export). The three stations were characterized by a strong nitracline and contrasted deep chlorophyll maximum depths, which were lower in the oligotrophic Melanesian archipelago (MA, stations LD A and LD B) than in the ultra-oligotrophic waters of the South Pacific Gyre (SPG, station LD C). N2 fixation rates were extremely high at both LD A (593 ± 51 µmol N m-2 d-1) and LD B (706 ± 302 µmol N m-2 d-1), and the diazotroph community was dominated by Trichodesmium. N2 fixation rates were lower (59 ± 16 µmol N m-2 d-1) at LD C, and the diazotroph community was dominated by unicellular N2-fixing cyanobacteria (UCYN). At all stations, N2 fixation was the major source of new N (> 90 %) before atmospheric deposition and upward nitrate fluxes induced by turbulence. N2 fixation contributed circa 13-18 % of primary production in the MA region and 3 % in the SPG water and sustained nearly all new primary production at all stations. The e ratio (e ratio = particulate carbon export / primary production) was maximum at LD A (9.7 %) and was higher than the e ratio in most studied oligotrophic regions (leading to N accumulation in the upper layer appears as a characteristic of the WTSP during the summer season.

  16. Threshold Dynamics of a Stochastic Chemostat Model with Two Nutrients and One Microorganism

    Directory of Open Access Journals (Sweden)

    Jian Zhang

    2017-01-01

    Full Text Available A new stochastic chemostat model with two substitutable nutrients and one microorganism is proposed and investigated. Firstly, for the corresponding deterministic model, the threshold for extinction and permanence of the microorganism is obtained by analyzing the stability of the equilibria. Then, for the stochastic model, the threshold of the stochastic chemostat for extinction and permanence of the microorganism is explored. Difference of the threshold of the deterministic model and the stochastic model shows that a large stochastic disturbance can affect the persistence of the microorganism and is harmful to the cultivation of the microorganism. To illustrate this phenomenon, we give some computer simulations with different intensity of stochastic noise disturbance.

  17. Biogenic amines degradation by microorganisms isolated from cheese

    Directory of Open Access Journals (Sweden)

    Irena Butor

    2017-01-01

    Full Text Available The aim of this study was the isolation and characterization of microorganisms able to degrade biogenic amines and their identification. Individual microorganisms were obtained by isolation from commercially available foodstuffs and food produced in the technological laboratories of Faculty of Technology, Tomas Bata University in Zlín and subsequently identified by MALDI-TOF MS. The results of MALDI-TOF MS identification were verified by 16S rRNA sequenation. In this work was studied the ability of 5 bacterial strains positive to biogenic amines degradation isolated from dairy products to decrease biogenic amines content in vitro and quantified reduction in the concentration of biogenic amines tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine and tyramine. The level of degradation (decrease of biogenic amines was determined on the base of the ability to grow in media with biogenic amines as the sole source carbon and nitrogen. The isolated strains with the ability of degradation of one or more biogenic amines were cultured in medium supplemented with relevant biogenic amines, the media derivatized with dansyl chloride and these amines separated by HPLC at a wavelength of 254 nm. From five tested strains identified as Bacillus subtilis, Bacillus pumilus, Enterobacter cloacae, Rhizobium radiobacter and Acinetobacter pitii, isolated from gouda type cheese, the greatest ability of degradation was observed in Bacillus subtilis, which was capable to degrade almost all amount of histamine, cadaverine and putrescine. Other four strains showed a lower rate of degradation than Bacillus subtilis, but the ability to degrade biogenic amines with these microorganisms was still significant.

  18. Insolubilization of technetium by microorganisms in waterlogged soils

    International Nuclear Information System (INIS)

    Ishii, Nobuyoshi; Tagami, Keiko

    2003-01-01

    In order to clarify the technetium behavior in paddy field ecosystem, insolubilization of technetium in the water covering waterlogged soils was studied. Fourteen soils collected from paddy fields (9 samples) and upland fields (5 samples) were waterlogged for 7 days. After the collection of water covering the waterlogged soils, a radio tracer 95m TcO 4 - was added to the water. After 4 days incubation of the water, the tracer was separated into four fractions: insoluble, pertechnetate, cationic, and other forms of technetium. On an average, 13% of the 95m TcO 4 - changed to insoluble forms and the maximum ratio of the insolubilization was 76%. This result shows that insolubilization of technetium can occur in the water covering the waterlogged soils. Subsequently, mechanisms of Tc insolubilization were studied using the sample that showed the maximum insolubilization of Tc among the soil samples. When microorganisms were removed from the water by filtration, insoluble forms of Tc decreased to 3.6%. In contrast, the insolubilization ratio increased to 86% by the addition of organic substrates. The insolubilization, therefore, was caused by microorganisms. Furthermore, the addition of antibiotics on bacteria resulted in 23% of the insolubilization, while the antibiotic on fungi did not affect on the insolubilization. If the insolubilization were caused by biosorption, the insolubilization ratio would not decrease for the sample added antibiotics on bacteria. Therefore, these results suggest that the insolubilization of technetium is caused by bioaccumulation of living bacteria. Because the cultures with 95m TcO 4 - were incubated under aerobic conditions, technetium-insolubilizing microorganisms would presumably be aerobic bacteria. (author)

  19. Antibacterial Effect of Copper on Microorganisms Isolated from Bovine Mastitis

    Science.gov (United States)

    Reyes-Jara, Angelica; Cordero, Ninoska; Aguirre, Juan; Troncoso, Miriam; Figueroa, Guillermo

    2016-01-01

    The antimicrobial properties of copper have been recognized for several years; applying these properties to the prevention of diseases such as bovine mastitis is a new area of research. The aim of the present study was to evaluate in vitro the antimicrobial activity of copper on bacteria isolated from subclinical and clinical mastitis milk samples from two regions in Chile. A total of 327 microorganisms were recovered between March and September 2013, with different prevalence by sample origin (25 and 75% from the central and southern regions of Chile, respectively). In the central region, Escherichia coli and coagulase negative Staphylococci (CNS) were the most frequently detected in clinical mastitis cases (33%), while in the southern region S. uberis, S. aureus, and CNS were detected with frequencies of 22, 21, and 18%, respectively. Antibiotic susceptibility studies revealed that 34% of isolates were resistant to one or more antibiotics and the resistance profile was different between bacterial species and origins of isolation of the bacteria. The minimum inhibitory concentration of copper (MIC-Cu) was evaluated in all the isolates; results revealed that a concentration as low as 250 ppm copper was able to inhibit the great majority of microorganisms analyzed (65% of isolates). The remaining isolates showed a MIC-Cu between 375 and 700 ppm copper, and no growth was observed at 1000 ppm. A linear relationship was found between the logarithm of viable bacteria number and time of contact with copper. With the application of the same concentration of copper (250 ppm), CNS showed the highest tolerance to copper, followed by S. uberis and S. aureus; the least resistant was E. coli. Based on these in vitro results, copper preparations could represent a good alternative to dipping solutions, aimed at preventing the presence and multiplication of potentially pathogenic microorganisms involved in bovine mastitis disease. PMID:27199953

  20. Surfactant producing TNT-degrading microorganisms for bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Vorobyov, A.; Marchenko, A.; Rudneva, O.; Borovick, R. [Research Center for Toxicology and Hygienic Regulation of Biopreparations, Serpukhov, Moscow region (Russian Federation); Radosevich, M. [Univ. of Delaware, Newark (United States). Dept. of Plant and Soil Sciences

    2003-07-01

    In general the biodegradation of nitroaromatic hydrocarbons is influenced by their bioavailability. 2,4,6-trinitrotoluene is very poorly soluble in water. TNT is easily adsorbed to clay or humus fractions in the soil, and pass very slowly to the aqueous phase, where microorganisms metabolize it. Biosurfactants that increase TNT solubility and improve its bioavailability can thereby accelerate degradation. Pure cultures of microorganisms-TNT degraders were isolated by the method of enrichment cultures from samples of different-type soil contaminated by TNT (soddy-podzol, black earth, and gray forest ones). From 28 soil samples 35 isolates of microorganisms degrading TNT were taken. The isolated soil samples had been tested for availability of microbial activity towards TNT. By10 g of air-dried soil, 10 ml of distilled water, and 2 mg of TNT were placed into 750 ml shaken flasks. The flasks were incubated at 150 rev/min and 24 C. Glucose, sodium succinate or sodium acetate had been used as co-substrates. The ability of the strains to produce surfactants was studied by drop collapsing test and direct measuring of surface tension of cultural liquid after cultivation with TNT. Cells of the strains were cultivated on solid and liquid nutrient media. For drop collapsing test the cells were cultivated on solid nutrient media; the separated colonies were suspended in distilled water. Drop sustainability test ws conducted on a standard 96-well plates coated with a thin layer of vaseline oil. Surface tension of cultural liquid ws measured after cultivation of strains in the presence of TNT with the use of a ring tensiometer. Before measuring of surface tension microbial cells were collected from liquid culture by centrifugation. (orig.)

  1. Effectiveness of chitosan against wine-related microorganisms.

    Science.gov (United States)

    Bağder Elmaci, Simel; Gülgör, Gökşen; Tokatli, Mehmet; Erten, Hüseyin; İşci, Asli; Özçelik, Filiz

    2015-03-01

    The antimicrobial action of chitosan against wine related microorganisms, including Lactobacillus plantarum, Saccharomyces cerevisiae, Oeonococcus oeni, Lactobacillus hilgardii, Brettanomyces bruxellensis, Hanseniaspora uvarum and Zygosaccharomyces bailii was examined in laboratory media. In order to assess the potential applicability of chitosan as a microbial control agent for wine, the effect of chitosan, applied individually and/or in combination with sulphur dioxide (SO2), on the growth of microorganisms involved in various stages of winemaking and on the fermentative performance of S. cerevisiae was investigated. Of the seven wine-related microorganisms studied, S. cerevisiae exhibited the strongest resistance to antimicrobial action of chitosan in laboratory media with a minimum inhibitory concentration (MIC) greater than 2 g/L. L. hilgardii, O. oeni and B. bruxellensis were the most susceptible to chitosan since they were completely inactivated by chitosan at 0.2 g/L. The MIC of chitosan for L. plantarum, H. uvarum and Z. bailii was 2, 0.4 and 0.4 g/L, respectively. In wine experiments, it was found that chitosan had a retarding effect on alcoholic fermentation without significantly altering the viability and the fermentative performance of S. cerevisiae. With regard to non-Saccharomyces yeasts (H. uvarum and Z. bailii) involved in winemaking, the early deaths of these yeasts in mixed cultures with S. cerevisiae were not probably due to the antimicrobial action of chitosan but rather due to ethanol produced by the yeasts. The complex interactions between chitosan and wine ingredients as well as microbial interactions during wine fermentation considerably affect the efficacy of chitosan. It was concluded that chitosan was worthy of further investigation as an alternative or complementary preservative to SO2 in wine industry.

  2. Analysis of the global ocean sampling (GOS) project for trends in iron uptake by surface ocean microbes.

    Science.gov (United States)

    Toulza, Eve; Tagliabue, Alessandro; Blain, Stéphane; Piganeau, Gwenael

    2012-01-01

    Microbial metagenomes are DNA samples of the most abundant, and therefore most successful organisms at the sampling time and location for a given cell size range. The study of microbial communities via their DNA content has revolutionized our understanding of microbial ecology and evolution. Iron availability is a critical resource that limits microbial communities' growth in many oceanic areas. Here, we built a database of 2319 sequences, corresponding to 140 gene families of iron metabolism with a large phylogenetic spread, to explore the microbial strategies of iron acquisition in the ocean's bacterial community. We estimate iron metabolism strategies from metagenome gene content and investigate whether their prevalence varies with dissolved iron concentrations obtained from a biogeochemical model. We show significant quantitative and qualitative variations in iron metabolism pathways, with a higher proportion of iron metabolism genes in low iron environments. We found a striking difference between coastal and open ocean sites regarding Fe(2+) versus Fe(3+) uptake gene prevalence. We also show that non-specific siderophore uptake increases in low iron open ocean environments, suggesting bacteria may acquire iron from natural siderophore-like organic complexes. Despite the lack of knowledge of iron uptake mechanisms in most marine microorganisms, our approach provides insights into how the iron metabolic pathways of microbial communities may vary with seawater iron concentrations.

  3. Tides. Ocean Related Curriculum Activities.

    Science.gov (United States)

    Marrett, Andrea

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  4. Energy from rivers and oceans

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This chapter discusses the role energy from rivers and oceans may have in the energy future of the US. The topics discussed in the chapter include historical aspects of using energy from rivers and oceans, hydropower assessment including resources, technology and costs, and environmental and regulatory issues, ocean thermal energy conversion including technology and costs and environmental issues, tidal power, and wave power

  5. Application of microorganism to in-situ leaching mining

    International Nuclear Information System (INIS)

    Yu, Runlan; Sato, Kazuhiko; Nagara, Shuichi; Yamana, Satoshi

    1998-01-01

    In-situ leaching (ISL) technique has come into the spotlight recently because of its low production costs and low environmental impact. In China, development and application of economical ISL techniques are also being studied. To design a pilot scale ISL 'bioreactor' in China, applicability of microorganisms to ISL mining was evaluated at Ningyo Toge Works as a part of Scientist Exchange Program of the Science and Technology Agency. An overview of the indirect bio-ISL method with iron oxidizing bacteria, Thiobacillus ferroxidans (TF), and results from experiment to determine factors for the ISL 'bioreactor' are discussed. (author)

  6. Purification of soil contaminated by oil with microorganisms

    Directory of Open Access Journals (Sweden)

    Maira Kazankapova

    2013-05-01

    Full Text Available The paper presents the results of studying the influence of strains of Pseudomonas mendoсina H-3 and Oscillatoria С-3 on soil contaminated with petroleum and hydrocarbons. The changes in chemical composition of hydrocarbons were determined. The influence of strain on the soil was studied by IR spectroscopy and chromatography. It was found that microorganisms can break down paraffinic and aromatic petroleum hydrocarbons.

  7. Stringy and Membranic Theory of Swimming of Micro-organisms

    OpenAIRE

    Kawamura, Masako; Nojiri, Shin'ichi; Sugamoto, Akio

    1996-01-01

    When the swimming of micro-organisms is viewed from the string and membrane theories coupled to the velocity field of the fluid, a number of interesting results are derived; 1) importance of the area (or volume) preserving algebra, 2) usefulness of the $N$-point Reggeon (membranic) amplitudes, and of the gas to liquid transition in case of the red tide issues, 3) close relation between the red tide issue and the generation of Einstein gravity, and 4) possible understanding of the three differ...

  8. Antimicrobial Effects of Garcinia Mangostana on Cariogenic Microorganisms.

    Science.gov (United States)

    Janardhanan, Sunitha; Mahendra, Jaideep; Girija, A S Smiline; Mahendra, Little; Priyadharsini, Vijayashree

    2017-01-01

    Garcinia mangostana commonly called as Mangosteen fruit has been used as an antibacterial agent since age old times. The mangosteen pericarp has proven to have antibacterial effect, but the effect of the same on cariogenic organisms has not been explored. The present study was an attempt to gain a better understanding of the antibacterial effect of mangosteen pericarp on the cariogenic bacteria, to unravel the therapeutic potential for the same. The aim of the study was to assess the antibacterial efficacy of the crude chloroform extract of mangosteen pericarp against cariogenic bacteria. The study was done under laboratory settings using an in vitro design. The microorganisms namely Streptococcus mutans, Streptococcus sanguis, Streptococcus salivarius, Streptococcus oralis and Lactobacillus acidophilus were procured from American Type Cell Culture (ATCC) and Microbial Type Culture Collection (MTCC) were revived and lawn cultured. The antibacterial effect of mangosteen pericarp was tested using agar well diffusion method on Trypticase Soy Agar-Blood Agar (TSA-BA) and de Man, Rogosa and Sharpe (MRS) agar media. The standard antiplaque agent chlorhexidine was used as the positive control. This cross-sectional, experimental study was done in Central Research laboratory, Meenakshi Ammal Dental College for period of eight weeks. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values were determined by microbroth dilution method. Statistical analysis was done by calculating the mean of the zones of inhibition on tested microorganisms. Mann-Whitney test was done to compare the zones of inhibition of mangosteen and chlorhexidine. The antibacterial bioassay showed the highest activity for Lactobacillus acidophilus (13.6 mm) and Streptococcus sanguis (13.6 mm), whereas, it showed a medium and low activity for Streptococcus oralis (11.3 mm), Streptococcus mutans (10.6 mm) and Streptococcus salivarius (3 mm) respectively. The MBC and MIC

  9. The future of starch bioengineering: GM microorganisms or GM plants?

    DEFF Research Database (Denmark)

    Hebelstrup, Kim; Sagnelli, Domenico; Blennow, Andreas

    2015-01-01

    , tubers and cereal grains to provide a GM crop as an alternative to the use of enzymes from GM microorganisms. We here discuss these techniques in relation to important structural features and modifications of starches such as: starch phosphorylation, starch hydrolysis, chain transfer/branching and novel...... concepts of hybrid starch-based polysaccharides. In planta starch bioengineering is generally challenged by yield penalties and inefficient production of the desired product. However, in some situations, GM crops for starch bioengineering without deleterious effects have been achieved....

  10. Analysis of bioremediation of pesticides by soil microorganisms

    Science.gov (United States)

    Ruml, Tomas; Klotz, Dietmar; Tykva, Richard

    1995-10-01

    The application of new pesticides requires careful monitoring of their distribution in the environment. The effect of the soil microflora on the stability of the [14C]- labelled juvenoid hormone analogue W-328 was estimated. The micro-organisms from two different soil samples were isolated and tested for their ability to decompose W-328. One bacterial strain, yeast and mold isolates, exhibited the degradation activity. The growth characteristics such as pH and temperature optima were determined. The degradation products were estimated using HPLC.

  11. Effect of Mixing on Microorganism Growth in Loop Bioreactors

    Directory of Open Access Journals (Sweden)

    A. M. Al Taweel

    2012-01-01

    Full Text Available The impact of mixing on the promotion of microorganism growth rate has been analyzed using a multiphase forced-circulation pipe-loop reactor model capable of identifying conditions under which it is possible to convert natural gas into Single-Cell Protein. The impact of mixing in the interphase mass transfer was found to exert a critical role in determining the overall productivity of the bioreactor, particularly at the high cell loadings needed to reduce the capital costs associated with the large-scale production needed for the production of relatively low-value SCP in a sustainable manner.

  12. Microbial and biochemical studies on phytase enzyme in some microorganisms

    International Nuclear Information System (INIS)

    Abdelbary, N.A.

    1997-01-01

    Mixed calcium and magnesium salts of phytic acid myoinositol hexa phosphoric acid are widely distributed in food stuffs of plant origin, they may bind essential proteins, phospholipids and microelements to form indigestible compounds. In this concern, destruction of phytic acid and its salts by different methods is very important, one of them is by using microbial phytase. This study aims to produce phytase enzyme from microorganisms and study the best conditions of production and purification and also the properties of the partially purified phytase. 22 figs., 29 tabs., 61 refs

  13. Exposure to airborne microorganisms and endotoxin in herb processing plants.

    Science.gov (United States)

    Dutkiewicz, J; Krysińska-Traczyk, E; Skórska, C; Sitkowska, J; Prazmo, Z; Golec, M

    2001-01-01

    Microbiological air sampling was performed in two herb processing plants located in eastern Poland. Air samples for determination of the levels of bacteria, fungi, dust and endotoxin were collected at 14 sites during cleaning, cutting, grinding, sieving, sorting and packing of 11 kinds of herbs (nettle, caraway, birch, celandine, marjoram, mint, peppermint, sage, St. John's wort, calamus, yarrow), used for production of medications, cosmetics and spices. It was found that processing of herbs was associated with a very high pollution of the air with bacteria, fungi, dust and endotoxin. The numbers of microorganisms (bacteria and fungi) in the air of herb processing plants ranged within 40.6-627.4 x 10(3) cfu/m3 (mean +/- S.D = 231.4 +/- 181.0 x 10(3) cfu/m3). The greatest concentrations were noted at the initial stages of production cycle, during cleaning, cutting and grinding of herbs. The numbers of airborne microorganisms were also significantly (pnettle, yarrow and mint. The values of the respirable fraction of airborne microflora in the examined facilities varied within a fairly wide range and were between 14.7-67.7%. The dominant microorganisms in the air of herb processing plants were mesophilic bacteria, among which endospore-forming bacilli (Bacillus spp.) and actinomycetes of the species Streptomyces albus were most numerous. Among Gram-negative bacteria, the most common was endotoxin-producing species Alcaligenes faecalis. Altogether, 37 species or genera of bacteria and 23 species or genera of fungi were identified in the air of herb processing plants, of these, 11 and 10 species or genera respectively were reported as having allergenic and/or immunotoxic properties. The concentrations of dust and bacterial endotoxin in the air of herb processing plants were large with extremely high levels at some sampling sites. The concentrations of airborne dust ranged within 3.2-946.0 mg/m3 (median 18.1 mg/m3), exceeding at 13 out of 14 sampling sites the Polish OEL

  14. 78 FR 32556 - Safety Zone; 2013 Ocean City Air Show, Atlantic Ocean; Ocean City, MD

    Science.gov (United States)

    2013-05-31

    ... FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History and Information The... Atlantic Ocean in Ocean City, MD. In recent years, there have been unfortunate instances of jets and planes...

  15. NCEI Standard Product: World Ocean Database (WOD)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The World Ocean Database (WOD) is the world's largest publicly available uniform format quality controlled ocean profile dataset. Ocean profile data are sets of...

  16. Crustal Ages of the Ocean Floor - Poster

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Crustal Ages of the Ocean Floor Poster was created at NGDC using the Crustal Ages of the Ocean Floor database draped digitally over a relief of the ocean floor...

  17. Remote Sensing of Ocean Color

    Science.gov (United States)

    Dierssen, Heidi M.; Randolph, Kaylan

    The oceans cover over 70% of the earth's surface and the life inhabiting the oceans play an important role in shaping the earth's climate. Phytoplankton, the microscopic organisms in the surface ocean, are responsible for half of the photosynthesis on the planet. These organisms at the base of the food web take up light and carbon dioxide and fix carbon into biological structures releasing oxygen. Estimating the amount of microscopic phytoplankton and their associated primary productivity over the vast expanses of the ocean is extremely challenging from ships. However, as phytoplankton take up light for photosynthesis, they change the color of the surface ocean from blue to green. Such shifts in ocean color can be measured from sensors placed high above the sea on satellites or aircraft and is called "ocean color remote sensing." In open ocean waters, the ocean color is predominantly driven by the phytoplankton concentration and ocean color remote sensing has been used to estimate the amount of chlorophyll a, the primary light-absorbing pigment in all phytoplankton. For the last few decades, satellite data have been used to estimate large-scale patterns of chlorophyll and to model primary productivity across the global ocean from daily to interannual timescales. Such global estimates of chlorophyll and primary productivity have been integrated into climate models and illustrate the important feedbacks between ocean life and global climate processes. In coastal and estuarine systems, ocean color is significantly influenced by other light-absorbing and light-scattering components besides phytoplankton. New approaches have been developed to evaluate the ocean color in relationship to colored dissolved organic matter, suspended sediments, and even to characterize the bathymetry and composition of the seafloor in optically shallow waters. Ocean color measurements are increasingly being used for environmental monitoring of harmful algal blooms, critical coastal habitats

  18. Enumeration of thraustochytrids (Heterotrophic microorganisms) from the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, S.

    The number of thraustochytrids in seawater has been estimated in several samples from the Arabian Sea by concentrating the sample on a glass-fibre filter and plating on a nutrient medium. The number ranged from 1 to 69 liter in the oceanic water...

  19. The Volvo Ocean Adventure

    Science.gov (United States)

    Boxall, S. R.; Flechter, S.; Byfield, Y.

    2003-04-01

    The Volvo Ocean Adventure is a web-based international programme for schools and young scientists in the 10-16 age range which was established in June 2001 (www.volvooceanadventure.org). Using the Volvo Ocean Race as its focus it made use of environmental data colletced from the yachts in the round the World race to introduce the public to a wide range of marine environmental topics including pollution, global climate change and fisheries. As well as web-based activities for the class room a variety of "road" shows were established with the race along with an international competition to encourage active participation by young people. The Adventure involved input from over 50 scientists form around the World with the first phase finishing in September 2002. The successes and lessons learned will be presented by the science co-ordinators of the project.

  20. Open ocean tide modelling

    Science.gov (United States)

    Parke, M. E.

    1978-01-01

    Two trends evident in global tidal modelling since the first GEOP conference in 1972 are described. The first centers on the incorporation of terms for ocean loading and gravitational self attraction into Laplace's tidal equations. The second centers on a better understanding of the problem of near resonant modelling and the need for realistic maps of tidal elevation for use by geodesists and geophysicists. Although new models still show significant differences, especially in the South Atlantic, there are significant similarities in many of the world's oceans. This allows suggestions to be made for future locations for bottom pressure gauge measurements. Where available, estimates of M2 tidal dissipation from the new models are significantly lower than estimates from previous models.

  1. On the Spot: Oceans

    OpenAIRE

    Male, Alan; Butterfield, Moira

    2000-01-01

    This a children's non-fiction, knowledge bearing picture book that is part of a Reader's Digest series called 'On the Spot'. The series deals with a range of topics related to the natural world and this one introduces its young audience to the ecosystems of the oceans. \\ud The publication was illustrated and designed by the author (Alan Male) and is technically described as a board book with interactive 'pop up' features, specifically conceived to engage children's discovery and learning thro...

  2. Islands in the Ocean

    Directory of Open Access Journals (Sweden)

    Elena Bagina

    2017-12-01

    Full Text Available Today’s China is an outpost of modern western architecture. All famous architects and firms build here. Having lost their historical context, the objects of traditional Chinese architecture become islands in the ocean of new development. Their destiny is controversial. Architectural masterpieces are perceived in a superficial manner not only by tourists, but also by local people. The link of times that used to be cherished in Chinese culture is being broken today.

  3. Ocean Bottom Seismic Scattering

    Science.gov (United States)

    1989-11-01

    EPR, the Clipperton and Orozco fracture zones , and along the coast of Mexico, were recorded for a two month period using ocean bottom seismometers...67. Tuthill, J.D., Lewis, B.R., and Garmany, J.D., 1981, Stonely waves, Lopez Island noise, and deep sea noise from I to 5 hz, Marine Geophysical...Patrol Pell Marine Science Library d/o Coast Guard R & D Center University of Rhode Island Avery Point Narragansett Bay Campus Groton, CT 06340

  4. Irradiation Effects on the Decontamination of Microorganisms in Honey

    International Nuclear Information System (INIS)

    Jo, Cheorun; Kim, Jae Kyung; Kang, Ho Jin; Lee Eun Young; Byun, Myung Woo

    2005-09-01

    Honey is usually contaminated with numerous microorganisms. Especially, the presence of the spore of Clostridium in honey is dangerous to infants and small children. To determine the effect of a gamma irradiation on the microorganisms in honey, our kinds of honeys (acacia flower, poly floral flower, native A, and native B) were irradiated (0, 5, and 10 kGy) and the total aerobic bacterial count, yeasts and molds, coliform, and Clostridium spp. were detected. In all the honeys, the coliform bacterial, yeast and molds counts were below. The limit of detection (< 101 cfu/g). Total aerobic bacterial and Clostridium spp counts ranged from 85 to 450 cfu/g and 0 to 450 cfu/g in the samples respectively. Acacia and poly floral flower honey were completely sterilized by a 5 kGy irradiation, and both the native honey A and B showed decreased populations of the total aerobic bacteria and Clostridium spp. with a 5 kGy irradiation. Therefore it is concluded that an irradiation treatment could be an effective tool to disinfect honey

  5. Dispersal of micro-organisms in commercial defeathering systems.

    Science.gov (United States)

    Allen, V M; Tinker, D B; Hinton, M H; Wathes, C M

    2003-03-01

    1. The extent of cross contamination between carcases and the dispersal of micro-organisms to the environs during defeathering was measured in a commercial processing plant. 2. Defeathering reduced the numbers of a marker organism, a nalidixic acid-resistant strain of Escherichia coli K12, on inoculated carcases but dispersed the organism on to preceding and following carcases. 3. The pattern of microbial dispersal during defeathering was similar for naturally occurring bacteria on the carcase, for example, total aerobic counts and counts of presumptive coliforms, suggesting that the marker organism mimics the natural situation realistically. 4. The majority of feathers, together with micro-organisms, were removed during the first 10 s of the defeathering process, which was completed in 45 s, indicating that control measures to minimise cross contamination would be most effective if applied in the early stages of the process. 5. The method of defeathering used by the machine influenced the pattern of microbial dispersal and the extent of cross contamination to other carcases on the same processing line.

  6. Continuous cultivation of photosynthetic microorganisms: Approaches, applications and future trends.

    Science.gov (United States)

    Fernandes, Bruno D; Mota, Andre; Teixeira, Jose A; Vicente, Antonio A

    2015-11-01

    The possibility of using photosynthetic microorganisms, such as cyanobacteria and microalgae, for converting light and carbon dioxide into valuable biochemical products has raised the need for new cost-efficient processes ensuring a constant product quality. Food, feed, biofuels, cosmetics and pharmaceutics are among the sectors that can profit from the application of photosynthetic microorganisms. Biomass growth in a photobioreactor is a complex process influenced by multiple parameters, such as photosynthetic light capture and attenuation, nutrient uptake, photobioreactor hydrodynamics and gas-liquid mass transfer. In order to optimize productivity while keeping a standard product quality, a permanent control of the main cultivation parameters is necessary, where the continuous cultivation has shown to be the best option. However it is of utmost importance to recognize the singularity of continuous cultivation of cyanobacteria and microalgae due to their dependence on light availability and intensity. In this sense, this review provides comprehensive information on recent breakthroughs and possible future trends regarding technological and process improvements in continuous cultivation systems of microalgae and cyanobacteria, that will directly affect cost-effectiveness and product quality standardization. An overview of the various applications, techniques and equipment (with special emphasis on photobioreactors) in continuous cultivation of microalgae and cyanobacteria are presented. Additionally, mathematical modeling, feasibility, economics as well as the applicability of continuous cultivation into large-scale operation, are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Fossil micro-organisms evidenced by electronic microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Prashnowsky, A.A.; Oberlies, F.; Burger, K.

    1983-04-01

    Fossil microorganisms in colonies and in the form of isolated cells (iron bacteria, fungi, actinomycetes etc.) were detected by electron microscopy of rocks containing remains of plant roots, carbonaceous substance, and strata of clay iron stone with ooids. These findings suggest an environment favourable to bacterial activity during sedimentation in the Upper Carboniferous and during the later processes of peat and coal formation. They also suggest that bacterial processes are an important factor in coal formation. Accurate data on coal formation can only be obtained by systematic biochemical studies. Analyses of the defined organic substances provide a better understanding of the conversion processes of the original substances. For example, the results of sterine analysis provide information on the mycoplancton, phytoplancton and zooplancton of the Upper Carboniferous. For some types of rock, the ratio of saponifiable to non-saponifiable constituents of the organic compounds yield information on stability under various geochemical conditions. The interactions between the various groups of microorganisms also play a major role in the solution of ecological problems.

  8. Microorganisms control during processing of germinated brown rice

    International Nuclear Information System (INIS)

    Suzuki, K.; Maekawa, T.

    1999-01-01

    In order to limit the growth of microorganisms during processing of germinated brown rice (GBR), three kinds of operations for sanitation control were investigated. For a surface-disinfection treatment of brown rice, soaking in 1% of sodium hypochlorite for 10min. and 0.1% of calcium preparation solutions for 10min. at 30°C, resulted in 2log decrease by aerobic plate count in culture water after 1h of the germination processing. Soaking in 10% of sodium hypochlorite for 10min. and 1% of calcium preparation solutions for 10min at 30°C were found to inhibit germination, respectively. During the germination processing, including aeration stage and non-aeration stage, continuous ultraviolet irradiation on the culture water in the water tank resulted in limited bacterial growth in culture water below 102CFU/ml by aerobic plate count. Moreover, the turbidity of the culture water was improved by filtration of the stored water using activated carbon-hollow fiber filter. The filtration by activated carbon-hollow fiber filter during the germination processing was an effective method to eliminate microorganisms and contamination factor during GBR production. It also improved the efficiency of ultraviolet irradiation effect on the culture water

  9. The future of starch bioengineering: GM microorganisms or GM plants?

    Directory of Open Access Journals (Sweden)

    Kim Henrik eHebelstrup

    2015-04-01

    Full Text Available Plant starches regularly require extensive modification to permit subsequent applications. Such processing is usually done by the use of chemical and/or physical treatments. The use of recombinant enzymes produced by large-scale fermentation of GM microorganisms is increasingly used in starch processing and modification, sometimes as an alternative to chemical or physical treatments. However, as a means to impart the modifications as early as possible in the starch production chain, similar recombinant enzymes may also be expressed in planta in the developing starch storage organ such as in roots, tubers and cereal grains to provide a GM crop as an alternative to the use of enzymes from GM microorganisms. We here discuss these techniques in relation to important structural features and modifications of starches such as: starch phosphorylation, starch hydrolysis, chain transfer/branching and novel concepts of hybrid starch-based polysaccharides. In planta starch bioengineering is generally challenged by yield penalties and inefficient production of the desired product. However in some situations, GM crops for starch bioengineering without deleterious effects have been achieved.

  10. Bioprospecting of lipolytic microorganisms obtained from industrial effluents

    Directory of Open Access Journals (Sweden)

    GREICE H.S. PEIL

    2016-01-01

    Full Text Available ABSTRACT The lipases have ability to catalyze diverse reactions and are important in different biotechnological applications. The aim of this work was to isolate and characterize microorganisms that produce lipases, from different food industry effluents localized in Pelotas, RS/Brazil. Bacteria were identified using Gram stain and biochemical tests (Vitek 2(r. Fungi were identified according to macro and micromorphology characteristics. The extracellular lipase production was evaluated using the Rhodamine B test and the enzymatic activity by titration. Twenty-one bacteria were isolated and identified as Klebsiella pneumoniae ssp. pneumoniae, Serratia marcescens, Enterobacter aerogenes, Raoultella ornithinolytica and Raoultella planticola. Were characterized isolated filamentous fungi by the following genera: Alternaria sp., Fusarium sp., Geotrichum sp., Gliocladium sp., Mucor sp., Paecilomyces sp. and Trichoderma sp. Extracellular lipase production was observed in 71.43% of the bacteria and 57.14% of the fungi. The bacterium that presented better promising enzymatic activity was E. aerogenes (1.54 U/ml however between fungi there was not significant difference between the four isolates. This study indicated that microorganisms lipase producers are present in the industrial effluents, as well as these enzymes have potential of biodegradation of lipid compounds.

  11. Bioprospecting of lipolytic microorganisms obtained from industrial effluents.

    Science.gov (United States)

    Peil, Greice H S; Kuss, Anelise V; Rave, Andrés F G; Villarreal, José P V; Hernandes, Yohana M L; Nascente, Patrícia S

    2016-01-01

    The lipases have ability to catalyze diverse reactions and are important in different biotechnological applications. The aim of this work was to isolate and characterize microorganisms that produce lipases, from different food industry effluents localized in Pelotas, RS/Brazil. Bacteria were identified using Gram stain and biochemical tests (Vitek 2(r)). Fungi were identified according to macro and micromorphology characteristics. The extracellular lipase production was evaluated using the Rhodamine B test and the enzymatic activity by titration. Twenty-one bacteria were isolated and identified as Klebsiella pneumoniae ssp. pneumoniae, Serratia marcescens, Enterobacter aerogenes, Raoultella ornithinolytica and Raoultella planticola. Were characterized isolated filamentous fungi by the following genera: Alternaria sp., Fusarium sp., Geotrichum sp., Gliocladium sp., Mucor sp., Paecilomyces sp. and Trichoderma sp. Extracellular lipase production was observed in 71.43% of the bacteria and 57.14% of the fungi. The bacterium that presented better promising enzymatic activity was E. aerogenes (1.54 U/ml) however between fungi there was not significant difference between the four isolates. This study indicated that microorganisms lipase producers are present in the industrial effluents, as well as these enzymes have potential of biodegradation of lipid compounds.

  12. Degradation of Parathion by Microorganisms from Cranberry Bogs

    International Nuclear Information System (INIS)

    Gorder, G.W.; Lichtenstein, E.P.

    1981-01-01

    Full text: Oxygen concentration and different carbon sources drastically altered parathion degradation in culture media inoculated with microorganisms from Wisconsin cranberry (Vaccinium macrocarpon Ait.) growing soils. These microorganisms also grew in basal salts media utilizing parathion as a sole carbon source. 14 CO 2 was produced only from phenyl-labelled parathion while 14 C-(ethyl)-parathion derived radiocarbon remained in the stale media of the soil-free cultures. Addition of 0.05% glucose to basal salts medium inhibited 14 C-(phenyl)-parathion degradation while the addition of 0.05% yeast extract to basal salts medium also inhibited microbiological degradation of the insecticide to 14 CO 2 , but to a lesser extent. Aminoparathion and aminoparaoxon were formed only in basal salts medium with 0.05% yeast extract. Aerobic cultures produced more 14 CO 2 from 14 C-(phenyl)-parathion and less aminoparathion than anaerobic cultures. Aminoparathion was more abundant in cultures with inocula obtained from the 18- to 23-cm layer than with culture inocula obtained from the 0- to 5-cm soil layer under both aerobic and anaerobic conditions. (author)

  13. MICROORGANISMS ANTIBIOTIC SENSITIVITY DETERMINATION IN URINARY TRACT INFECTIONS

    Directory of Open Access Journals (Sweden)

    Shapovalova O.V.

    2016-06-01

    Full Text Available Introduction. Nowadays Urinary tract infections (UTI are considered to be the most common bacterial infections. Escherichia coli is the most frequently uropathogen. Other microorganisms of the genera Enterococcus, Klebsiella, Enterobacter, Proteus, Morganella, Citrobacter, Serratia, Pseudomonas, Streptococcus, Staphylococcus, Candida are also isolated with variable frequency. In recent years there has been a decreasing tendency of the causative agents of UTI sensitivity to various antibiotics, which causes growth of an inefficiency treatment risk. In connection with the above the investigations were carried out with the purpose to identify the actual causative agents of bacteriuria and their sensitivity to antibiotics and antifungal drugs. Materials and methods. Bacteriological examination of urine was performed at 42 patients of SI "Sytenko Institute of Spine and Joint Pathology, AMS of Ukraine" clinic. The bacteriological method for determining the number of bacteria in the test material, cultural and bacterioscopic methods for identifying microorganisms and disk-diffusion method for sensitivity of microorganisms to antibiotics determining were used. The clinical material for the study was an average portion of the morning urine or urine collected by catheter. The biological material collection and bacteriological examination was carried by quantitative method, the isolated microorganisms identification and their sensitivity to antibiotics determining was performed by standard methods in accordance with current guidelines. We used the following antibiotics group to determine the microorganisms sensitivity: penicillin, cephalosporin, karbapenems, tetracyclines, aminoglycoside, fluoroquinolones, oxazolidinones, macrolides, lincosamides, glycopeptides, antifungal antibiotics. Results and discussion. During the biological material study 55 isolates of bacterial and fungal pathogens were obtained. The microorganisms’ concentration in urine was in

  14. International Depository Authority and its Role in Microorganism's Deposition.

    Science.gov (United States)

    Parashar, Abhishek

    2017-08-01

    After the World Trade Organization's agreement on Trade Related Aspect of Intellectual Property Right, patents have come into major play. Patenting of work related to live organisms that have medical, agricultural and other uses is always a tedious, complicated and controversial job. In view of this an agreement called as Budapest Treaty was passed in 1977 for deposition of microorganisms in culture collection centers for patent purpose. To make a culture collection center an IDA the culture center has to follow rules and regulations made in Budapest Treaty. Today several culture collection centers are working as International Depository Authority (IDA) in India and abroad that are storing microorganisms for patent purpose. India has two IDA units; one is Microbial Culture Collection in National Centre for Cell Science Pune, India, and second one is Microbial Type Culture Collection and Gene Bank at Institute of Microbial Technology Chandigarh, India. IDA units are important for valuable sample depositions, supply of cultures, characterization of samples and conservation of biological materials.

  15. Crocodylians evolved scattered multi-sensory micro-organs

    Science.gov (United States)

    2013-01-01

    Background During their evolution towards a complete life cycle on land, stem reptiles developed both an impermeable multi-layered keratinized epidermis and skin appendages (scales) providing mechanical, thermal, and chemical protection. Previous studies have demonstrated that, despite the presence of a particularly armored skin, crocodylians have exquisite mechanosensory abilities thanks to the presence of small integumentary sensory organs (ISOs) distributed on postcranial and/or cranial scales. Results Here, we analyze and compare the structure, innervation, embryonic morphogenesis and sensory functions of postcranial, cranial, and lingual sensory organs of the Nile crocodile (Crocodylus niloticus) and the spectacled caiman (Caiman crocodilus). Our molecular analyses indicate that sensory neurons of crocodylian ISOs express a large repertoire of transduction channels involved in mechano-, thermo-, and chemosensory functions, and our electrophysiological analyses confirm that each ISO exhibits a combined sensitivity to mechanical, thermal and pH stimuli (but not hyper-osmotic salinity), making them remarkable multi-sensorial micro-organs with no equivalent in the sensory systems of other vertebrate lineages. We also show that ISOs all exhibit similar morphologies and modes of development, despite forming at different stages of scale morphogenesis across the body. Conclusions The ancestral vertebrate diffused sensory system of the skin was transformed in the crocodylian lineages into an array of discrete multi-sensory micro-organs innervated by multiple pools of sensory neurons. This discretization of skin sensory expression sites is unique among vertebrates and allowed crocodylians to develop a highly-armored, but very sensitive, skin. PMID:23819918

  16. Beta particle dose rates to micro-organisms in soil

    International Nuclear Information System (INIS)

    Kabir, M.; Spiers, F.W.; Iinuma, Takeshi.

    1977-01-01

    Studies were made to estimate the beta-particle dose rates to micro-organisms of various sizes in soil. The small insects and organisms living in soil are constantly exposed to beta-radiation arising from naturally occuring radionuclides in soil as in this case no overlying tissue shields them. The technique of measuring beta-particle dose rate consisted of using of a thin plastic scintillator to measure the pulse height distribution as the beta particle traverses the scintillator. The integrated response was determined by the number and size of the photomultiplier pulses. From the data of soil analyses it was estimated that typically about 29% of the beta particles emitted per gm. of soil were contributed by the U/Ra series, 21% by the Th series and about 50% by potassium. By combining the individual spectra of these three radionuclides in the proportion found in a typical soil, a resultant spectrum was computed representing the energy distribution of the beta particles. The dose rate received by micro-organisms of different shape and size in soil was derived from the equilibrium dose rates combined with a 'Geometrical Factor' of the organisms. For small organisms, the dose rates did not vary between the spherical and cylindrical types, but in the case of larger organisms, the dose rates were found to be greater for the spherical types of the same diameter. (auth.)

  17. Influence of salinity and water content on soil microorganisms

    Directory of Open Access Journals (Sweden)

    Nan Yan

    2015-12-01

    Full Text Available Salinization is one of the most serious land degradation problems facing world. Salinity results in poor plant growth and low soil microbial activity due to osmotic stress and toxic ions. Soil microorganisms play a pivotal role in soils through mineralization of organic matter into plant available nutrients. Therefore it is important to maintain high microbial activity in soils. Salinity tolerant soil microbes counteract osmotic stress by synthesizing osmolytes which allows them to maintain their cell turgor and metabolism. Osmotic potential is a function of the salt concentration in the soil solution and therefore affected by both salinity (measured as electrical conductivity at a certain water content and soil water content. Soil salinity and water content vary in time and space. Understanding the effect of changes in salinity and water content on soil microorganisms is important for crop production, sustainable land use and rehabilitation of saline soils. In this review, the effects of soil salinity and water content on microbes are discussed to guide future research into management of saline soils.

  18. Biotechnical leaching of lean ores using heterotrophic microorganisms

    International Nuclear Information System (INIS)

    Schwartz, W.; Naeveke, R.

    1980-01-01

    After reporting briefly on leaching with Thiobacillus, it is discussed whether in those cases where thiobacilli fail to work the limits of microbial leaching are reached or still other groups of microorganisms will be suitable. In this relation the great number of carbon-heterotrophic fungi and bacteria have to be considered which are partly oligotrophic and occur e.g. in weathering biotopes of rocks and minerals and which may even include heavy metals in the dissolving processes of weathering. The active agents are, as far as is known up to now, organic acids which are produced by microorganisms and given off to the medium where they may combine with metals to form water-soluble complex compounds. In order to detect and isolate suitable strains of fungi and bacteria it will be necessary to work out a screening program which proceeds from general to special selections. Experiments to identify the active agents and the conditions of their production will have to follow. It remains still an open question whether such studies will result in technical processes. Mass production processes which are possible with the carbon-autotrophic and acidophilic thiobacilli are less probable than special processes to get hold of rare and economically valuable metals whose extraction would be difficult by other means. (orig.) [de

  19. Effects of Hangeshashinto on Growth of Oral Microorganisms

    Directory of Open Access Journals (Sweden)

    Haruka Fukamachi

    2015-01-01

    Full Text Available Oral mucositis (OM in cancer patients induced by chemotherapy or radiotherapy has a significant impact on quality of life, and causes considerable morbidity. Oral microorganisms are likely to intensify the inflammatory process and aggravate the formation of ulcers. Hangeshashinto (HST, a Japanese kampo medicine, has been reported to be effective when used as a gargle for the treatment of OM. To clarify the effects of HST on oral microorganisms, we assessed its antimicrobial activity against 27 microbial species, including 19 oral bacteria and one fungus. HST extract inhibited the growth of Gram-negative bacteria, including Fusobacterium nucleatum, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella melaninogenica, Tannerella forsythia, Treponema denticola, and Porphyromonas asaccharolytica, though inhibitory effects were less pronounced for Gram-positive bacteria and the fungal strain. We then investigated the effects of antibacterial activities on 15 purified ingredients of HST and determined that baicalein, berberine, coptisine, [6]-shogaol, and homogentisic acid actively inhibited the growth of these bacteria. These findings showed that HST inhibits the growth of specific Gram-negative periodontopathogenic bacteria, which are significant pathogens in OM, without disturbing the normal oral flora. Our data suggest that HST may be a useful treatment for OM in patients undergoing anticancer treatment.

  20. Endophytic microorganisms--promising applications in bioremediation of greenhouse gases.

    Science.gov (United States)

    Stępniewska, Z; Kuźniar, A

    2013-11-01

    Bioremediation is a technique that uses microbial metabolism to remove pollutants. Various techniques and strategies of bioremediation (e.g., phytoremediation enhanced by endophytic microorganisms, rhizoremediation) can mainly be used to remove hazardous waste from the biosphere. During the last decade, this specific technique has emerged as a potential cleanup tool only for metal pollutants. This situation has changed recently as a possibility has appeared for bioremediation of other pollutants, for instance, volatile organic compounds, crude oils, and radionuclides. The mechanisms of bioremediation depend on the mobility, solubility, degradability, and bioavailability of contaminants. Biodegradation of pollutions is associated with microbial growth and metabolism, i.e., factors that have an impact on the process. Moreover, these factors have a great influence on degradation. As a result, recognition of natural microbial processes is indispensable for understanding the mechanisms of effective bioremediation. In this review, we have emphasized the occurrence of endophytic microorganisms and colonization of plants by endophytes. In addition, the role of enhanced bioremediation by endophytic bacteria and especially of phytoremediation is presented.

  1. Microorganisms with Claimed Probiotic Properties: An Overview of Recent Literature

    Science.gov (United States)

    Fijan, Sabina

    2014-01-01

    Probiotics are defined as live microorganisms, which when administered in adequate amounts, confer a health benefit on the host. Health benefits have mainly been demonstrated for specific probiotic strains of the following genera: Lactobacillus, Bifidobacterium, Saccharomyces, Enterococcus, Streptococcus, Pediococcus, Leuconostoc, Bacillus, Escherichia coli. The human microbiota is getting a lot of attention today and research has already demonstrated that alteration of this microbiota may have far-reaching consequences. One of the possible routes for correcting dysbiosis is by consuming probiotics. The credibility of specific health claims of probiotics and their safety must be established through science-based clinical studies. This overview summarizes the most commonly used probiotic microorganisms and their demonstrated health claims. As probiotic properties have been shown to be strain specific, accurate identification of particular strains is also very important. On the other hand, it is also demonstrated that the use of various probiotics for immunocompromised patients or patients with a leaky gut has also yielded infections, sepsis, fungemia, bacteraemia. Although the vast majority of probiotics that are used today are generally regarded as safe and beneficial for healthy individuals, caution in selecting and monitoring of probiotics for patients is needed and complete consideration of risk-benefit ratio before prescribing is recommended. PMID:24859749

  2. Turbines in the ocean

    Science.gov (United States)

    Smith, F. G. W.; Charlier, R. H.

    1981-10-01

    It is noted that the relatively high-speed ocean currents flowing northward along the east coast of the U.S. may be able to supply a significant proportion of the future electric power requirements of urban areas. The Gulf Stream core lies only about 20 miles east of Miami; here its near-surface water reaches velocities of 4.3 miles per hour. Attention is called to the estimate that the energy available in the current of the Gulf Stream adjacent to Florida is approximately equivalent to that generated by 25 1,000-megawatt power plants. It is also contended that this power could be produced at competitive prices during the 1980s using large turbines moored below the ocean surface near the center of the Stream. Assuming an average ocean-current speed between 4 and 5 knots at the current core, the power density of a hydroturbine could reach 410 watts per square foot, about 100 times that of a wind-driven device of similar scale operating in an airflow of approximately 11 knots.

  3. Ocean Observations of Climate Change

    Science.gov (United States)

    Chambers, Don

    2016-01-01

    The ocean influences climate by storing and transporting large amounts of heat, freshwater, and carbon, and exchanging these properties with the atmosphere. About 93% of the excess heat energy stored by the earth over the last 50 years is found in the ocean. More than three quarters of the total exchange of water between the atmosphere and the earth's surface through evaporation and precipitation takes place over the oceans. The ocean contains 50 times more carbon than the atmosphere and is at present acting to slow the rate of climate change by absorbing one quarter of human emissions of carbon dioxide from fossil fuel burning, cement production, deforestation and other land use change.Here I summarize the observational evidence of change in the ocean, with an emphasis on basin- and global-scale changes relevant to climate. These include: changes in subsurface ocean temperature and heat content, evidence for regional changes in ocean salinity and their link to changes in evaporation and precipitation over the oceans, evidence of variability and change of ocean current patterns relevant to climate, observations of sea level change and predictions over the next century, and biogeochemical changes in the ocean, including ocean acidification.

  4. Springer handbook of ocean engineering

    CERN Document Server

    Xiros, Nikolaos

    2016-01-01

    The handbook is the definitive reference for the interdisciplinary field that is ocean engineering. It integrates the coverage of fundamental and applied material and encompasses a diverse spectrum of systems, concepts and operations in the maritime environment, as well as providing a comprehensive update on contemporary, leading-edge ocean technologies. Coverage includes but is not limited to; an overview of ocean science, ocean signals and instrumentation, coastal structures, developments in ocean energy technologies, and ocean vehicles and automation. The handbook will be of interest to practitioners in a range of offshore industries and naval establishments as well as academic researchers and graduate students in ocean, coastal, offshore, and marine engineering and naval architecture.

  5. Ocean circulation generated magnetic signals

    DEFF Research Database (Denmark)

    Manoj, C.; Kuvshinov, A.; Maus, S.

    2006-01-01

    Conducting ocean water, as it flows through the Earth's magnetic field, generates secondary electric and magnetic fields. An assessment of the ocean-generated magnetic fields and their detectability may be of importance for geomagnetism and oceanography. Motivated by the clear identification...... of ocean tidal signatures in the CHAMP magnetic field data we estimate the ocean magnetic signals of steady flow using a global 3-D EM numerical solution. The required velocity data are from the ECCO ocean circulation experiment and alternatively from the OCCAM model for higher resolution. We assume...... of the magnetic field, as compared to the ECCO simulation. Besides the expected signatures of the global circulation patterns, we find significant seasonal variability of ocean magnetic signals in the Indian and Western Pacific Oceans. Compared to seasonal variation, interannual variations produce weaker signals....

  6. Long-range transport of airborne microbes over the global tropical and subtropical ocean

    KAUST Repository

    Mayol, Eva; Arrieta, J M; Jimé nez, Maria A.; Martí nez-Asensio, Adriá n; Garcias Bonet, Neus; Dachs, Jordi; Gonzá lez-Gaya, Belé n; Royer, Sarah-J.; Bení tez-Barrios, Veró nica M.; Fraile-Nuez, Eugenio; Duarte, Carlos M.

    2017-01-01

    The atmosphere plays a fundamental role in the transport of microbes across the planet but it is often neglected as a microbial habitat. Although the ocean represents two thirds of the Earth's surface, there is little information on the atmospheric microbial load over the open ocean. Here we provide a global estimate of microbial loads and air-sea exchanges over the tropical and subtropical oceans based on the data collected along the Malaspina 2010 Circumnavigation Expedition. Total loads of airborne prokaryotes and eukaryotes were estimated at 2.2 × 1021 and 2.1 × 1021 cells, respectively. Overall 33-68% of these microorganisms could be traced to a marine origin, being transported thousands of kilometres before re-entering the ocean. Moreover, our results show a substantial load of terrestrial microbes transported over the oceans, with abundances declining exponentially with distance from land and indicate that islands may act as stepping stones facilitating the transoceanic transport of terrestrial microbes.The extent to which the ocean acts as a sink and source of airborne particles to the atmosphere is unresolved. Here, the authors report high microbial loads over the tropical Atlantic, Pacific and Indian oceans and propose islands as stepping stones for the transoceanic transport of terrestrial microbes..

  7. Long-range transport of airborne microbes over the global tropical and subtropical ocean

    KAUST Repository

    Mayol, Eva

    2017-07-28

    The atmosphere plays a fundamental role in the transport of microbes across the planet but it is often neglected as a microbial habitat. Although the ocean represents two thirds of the Earth\\'s surface, there is little information on the atmospheric microbial load over the open ocean. Here we provide a global estimate of microbial loads and air-sea exchanges over the tropical and subtropical oceans based on the data collected along the Malaspina 2010 Circumnavigation Expedition. Total loads of airborne prokaryotes and eukaryotes were estimated at 2.2 × 1021 and 2.1 × 1021 cells, respectively. Overall 33-68% of these microorganisms could be traced to a marine origin, being transported thousands of kilometres before re-entering the ocean. Moreover, our results show a substantial load of terrestrial microbes transported over the oceans, with abundances declining exponentially with distance from land and indicate that islands may act as stepping stones facilitating the transoceanic transport of terrestrial microbes.The extent to which the ocean acts as a sink and source of airborne particles to the atmosphere is unresolved. Here, the authors report high microbial loads over the tropical Atlantic, Pacific and Indian oceans and propose islands as stepping stones for the transoceanic transport of terrestrial microbes..

  8. Mechanisms of hexavalent chromium resistance and removal by microorganisms.

    Science.gov (United States)

    Joutey, Nezha Tahri; Sayel, Hanane; Bahafid, Wifak; El Ghachtouli, Naïma

    2015-01-01

    Chromium has been and is extensively used worldwide in multiple industrial processes and is routinely discharged to the environment from such processes. Therefore, this heavy metal is a potential threat to the environment and to public health, primarily because it is non-biodegradable and environmentally persistent. Chromium exists in several oxidation states, the most stable of which are trivalent Cr(Ill) and hexavalent Cr(VI) species. Each species possesses its own individual chemical characteristics and produces its own biological effects. For example, Cr (Ill) is an essential oligoelement for humans, whereas Cr(VI) is carcinogenic and mutagenic. Several chemical methods are used to remove Cr(VI) from contaminated sites. Each of these methods has advantages and disadvantages. Currently, bioremediation is often the preferred method to deal with Cr contaminated sites, because it is eco-friendly, cost-effective and is a "natural" technology. Many yeast, bacterial and fungal species have been assessed for their suitability to reduce or remove Cr(VI) contamination. The mechanisms by which these microorganisms resist and reduce Cr(VI) are variable and are species dependent. There are several Cr-resistance mechanisms that are displayed by microorganisms. These include active efflux of Cr compounds, metabolic reduction of Cr(VI) to Cr (ill), and either intercellular or extracellular prec1p1tation. Microbial Cr (VI) removal typically involves three stages: binding of chromium to the cell surface, translocation of chromium into the cell, and reduction of Cr(VI) to Cr (ill). Cr(VI) reduction by microorganisms may proceed on the cell surface, outside the cell, or intracellularly, either directly via chromate reductase enzymes, or indirectly via metabolite reduction of Cr(VI). The uptake of chromium ions is a biphasic process. The primary step is known as biosorption, a metabolic energyindependent process. Thereafter, bioaccumulation occurs, but is much slower, and is

  9. Northern blot analysis to investigate the abundance of microorganisms

    International Nuclear Information System (INIS)

    Krause, D.O.

    2005-01-01

    Modern molecular microbial ecology has its origins in the analysis of informative macromolecules. Zuckerkandl and Pauling proposed that certain macromolecules are relatively free from evolutionary pressure and may be considered a molecular document of the evolutionary history of the organism that carries the molecule. In their paper, they proposed that the sequence difference of a molecule is proportional to the evolutionary distance between the organisms; the greater the sequence differences the greater the evolutionary distance. A significant breakthrough with this approach in microbial systematics resulted from the work of Woese and Fox who used oligonucleotide cataloguing of 16S-rRNA to delineate the phylogenetic relationships between microorganisms. By using this approach, it was possible to demonstrate that all life on earth could be divided into three kingdoms: eukarya, procarya and archaea. The unique findings of this research was that the archaea, made up of many methanogenic and thermophilic microorganisms, were probably the most ancient life forms on earth and were not bacteria at all. One of the first applications of rRNA genes was the recovery of unique 5S-rRNA sequences from the Yellowstone hot spring. Even though the statistical utility of the short 5S sequences was limited, it demonstrated that there was a great deal of uncultured diversity within the ecosystem. This uncultured diversity was demonstrated to be highly significant when clone libraries were constructed from the Yellowstone hot spring. Universal PCR primers were used to amplify 16S-rDNA from the microbial community, and these mixed amplicons were cloned into a vector. Each insert, potentially representing a different species, was sequenced giving a snapshot of microbial diversity in the sample. A unique feature of the rRNAs is that they are hierarchical molecules. This means that there are regions where the molecules is highly conserved, others where the sequence is variable, and even

  10. [Prevalence of associated microorganisms in genital discharge, Argentina].

    Science.gov (United States)

    Di Bartolomeo, Susana; Rodriguez Fermepin, Marcelo; Sauka, Diego H; Alberto de Torres, Ramón

    2002-10-01

    There was a significant increase in the number of women demanding gynecological care in public hospital of the Great Buenos Aires, Argentina, between 1997 and 1998. It was necessary to update the prevalence of associated microorganisms in order to review the laboratory support and adjust prevention and control guidelines. Samples from vaginal and endocervical discharge, from total cases: 84 adolescents (15 to 19 years) and 784 adults (20-60 years) attended in 1997-1998, were studied. Neisseria gonorrhoeae, Streptococcus agalactiae, Trichomonas vaginalis, Candida spp, and bacterial vaginosis, were diagnosed applying direct detection methods and specific culture isolation. Chlamydia trachomatis (antigen detection), Ureaplasma urealyticum and Mycoplasma hominis (culture) were also studied in part of the population. Patient care increased steadily from 1997 and there was an increase of 2.1 times from the first semester to the last one in 1998. Bacterial vaginosis was the most prevalent disease in the adult group, with 23.8%; followed by Candida spp 17.8%; S. agalactiae 5.6%; T.vaginalis 2.4%. In 50.3% of total adult cases neither bacterial vaginosis or presence of any sought microorganisms, was detected. In the adolescents group the most frequent detection was Candida spp with a 29.7%; bacterial vaginosis in 17.8%; followed by S. agalactiae 3.6%, T.vaginalis 2.4%. Also in this group on an important number of cases, 46.4%, none bacterial vaginosis or the presence of the sought microorganism were found. In some of the adult group, C. trachomatis (7/400) 1.76%, U. urealyticum (209/340) 61.4% and M. hominis (45/272) 16.5% were detected. Bacterial vaginosis and Candida spp prevalence is important in both groups. The absence of N. gonorrhoeae and lower prevalence of T. vaginalis and C. trachomatis is remarkable. A high prevalence of U. urealyticum and M. hominis were also detected, but the actual pathogenic role in adult women is still under discussion. The significant

  11. MICROORGANISMS: A MARVELOUS SOURCE OF SINGLE CELL PROTEINS

    Directory of Open Access Journals (Sweden)

    Agam Nangul

    2013-08-01

    Full Text Available The increasing global population living below the poverty line is driving the scientific community to search for non-conventional protein sources that can replace conventional expensive ones. Microbial proteins, or single-cell protein (SCP, represent a potential future nutrient source for human food and animal feed. These microbial proteins can be grown rapidly on substrates with minimum dependence on soil, water and climate conditions. They can be produced from algae, fungi and bacteria the chief sources of SCP. It is convenient to use microorganisms for production of SCP as they grow rapidly and have high protein content. Industrially, they can be produced from algal biomass, yeast, fungi. There are several other ways of getting SCP as well. Despite numerous advantages of SCP, they have disadvantages and toxic effects too, especially related to mycotoxins and bacterial toxins.

  12. Rheological behavior of raw natural rubber coagulated by microorganisms

    Directory of Open Access Journals (Sweden)

    Zhifen Wang

    2014-01-01

    Full Text Available Tests of the strain sweep, frequency sweep and stress relaxation for raw natural rubber coagulated by microorganisms (NR-m and raw natural rubber coagulated by acid (NR-a were carried out with the use of a rubber process analyzer (RPA. The results showed that the storage torque, complex viscosity of NR-m were higher than those of NR-a while the loss factor was lower. The effect of temperature on viscosity of raw NR was studied following the Arrhenious-Frenkel-Eyring model. The viscous flow behavior of NR-m was poorer than those of NR-a. Furthermore, stress relaxation measurements of raw NR showed a longer period of relaxation for NR-m.

  13. Opportunistic microorganisms in patients undergoing antibiotic therapy for pulmonary tuberculosis

    Directory of Open Access Journals (Sweden)

    Silvia Maria Rodrigues Querido

    2011-12-01

    Full Text Available Antimicrobial therapy may cause changes in the resident oral microbiota, with the increase of opportunistic pathogens. The aim of this study was to compare the prevalence of Candida, Staphylococcus, Pseudomonas and Enterobacteriaceae in the oral cavity of fifty patients undergoing antibiotic therapy for pulmonary tuberculosis and systemically healthy controls. Oral rinsing and subgingival samples were obtained, plated in Sabouraud dextrose agar with chloramphenicol, mannitol agar and MacConkey agar, and incubated for 48 h at 37ºC. Candida spp. and coagulase-positive staphylococci were identified by phenotypic tests, C. dubliniensis, by multiplex PCR, and coagulase-negative staphylococci, Enterobacteriaceae and Pseudomonas spp., by the API systems. The number of Candida spp. was significantly higher in tuberculosis patients, and C. albicans was the most prevalent specie. No significant differences in the prevalence of other microorganisms were observed. In conclusion, the antimicrobial therapy for pulmonary tuberculosis induced significant increase only in the amounts of Candida spp.

  14. Airborne microorganisms associated with waste management and recovery: biomonitoring methodologies

    Directory of Open Access Journals (Sweden)

    Anna Maria Coccia

    2010-01-01

    Full Text Available This paper presents preliminary results from a year-long indoor bioaerosol monitoring performed in three working environments of a municipal composting facility treating green and organic waste. Composting, whereby organic matter is stabilized through aerobic decomposition, requires aeration, causing the dispersion of microbial particles (microorganisms and associated toxins. Waste can, therefore, become a potential source of biological hazard. Bioaerosol samples were collected on a monthly basis. Through a comparison of results obtained using two samplers - the Surface Air System DUO SAS 360 and the BioSampler - the study aimed at assessing the presence of biological pollutants, and at contributing to the definition of standard sampling methods for bioaerosols leading, eventually, to the establishment of exposure limits for these occupational pollutants.

  15. Airborne microorganisms associated with waste management and recovery: biomonitoring methodologies.

    Science.gov (United States)

    Coccia, Anna Maria; Gucci, Paola Margherita Bianca; Lacchetti, Ines; Paradiso, Rosa; Scaini, Federica

    2010-01-01

    This paper presents preliminary results from a year-long indoor bioaerosol monitoring performed in three working environments of a municipal composting facility treating green and organic waste. Composting, whereby organic matter is stabilized through aerobic decomposition, requires aeration, causing the dispersion of microbial particles (microorganisms and associated toxins). Waste can, therefore, become a potential source of biological hazard. Bioaerosol samples were collected on a monthly basis. Through a comparison of results obtained using two samplers - the Surface Air System DUO SAS 360 and the BioSampler - the study aimed at assessing the presence of biological pollutants, and at contributing to the definition of standard sampling methods for bioaerosols leading, eventually, to the establishment of exposure limits for these occupational pollutants.

  16. Testing Method of Degrading Heavy Oil Pollution by Microorganisms

    Science.gov (United States)

    Wu, Qi; Zhao, Lin; Ma, Aijin

    2018-01-01

    With the development of human society, we are more and more relying on the petrochemical energy. The use of petrochemical energy not only brings us great convenience, but is also accompanied by a series of environmental pollution problems, especially oil pollution. Since it is impractical to restore all pollution problems, the proper use of some remedial measures, under the guidance of functional orientation, may be sufficient to minimize the risk of persistent and diffusing pollutants. In recent years, bioremediation technology has been gradually developed into a promising stage and has played a crucial role in the degradation of heavy oil pollution. Specially, microbes in the degradation of heavy oil have made a great contribution. This paper mainly summarizes the different kinds of microorganisms for degrading heavy oil and the detection method for degradation efficiency of heavy oil pollution.

  17. Isolation of microorganisms from red pepper powder and their radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Choi, E H; Kim, Y B; Lee, S R [Korea Atomic Energy Research Inst., Seoul (Republic of Korea)

    1977-01-01

    From samples of red pepper powder sold in Korea were isolated and identified 13 species of molds (Aspergillus amsteodami, Asp. chevalieri, Asp. clavatus, Asp. Flavus, Asp. janus var. effusus, Asp. oryzae, Asp. oryzae var. brevis, Asp. repens, Asp. sydowi, Asp. thomii, Asp. tubingensis, Penicillium thomii, Scopulariopsis brevicaulis) and 5 species of bacteria (Bacillus pumilus, Bac. subtilis, Micrococus luteus, M. varians, Staphylococcus aureus). Radiosensitivity of these microorganisms was examined to give D/sub 10/ values of 14-41 krad for molds, 11-24 krad for bacterial vegetative cells and 190-250 krad for bacterial spores. The red pepper powder was contaminated with 2-3x10/sup 2/ mold counts/g and 3-6x10/sup 7/ bacterial counts/g, which would be sufficiently destroyed by irradiating 200 krad r-rays.

  18. Prevalence of the pathogen microorganisms in raw cow milk

    Directory of Open Access Journals (Sweden)

    Angelovski Ljupco

    2009-11-01

    Full Text Available The aim of this study was to study the prevalence of Salmonella spp., Listeria spp., Staphylococcus spp. and E. coli in the raw cow milk. In this study 133 milk-tank samples from several milk collecting points were analysed. After the tests the following prevalence was detected: for Listeria spp. 13 positive samples (9.77%, with 9 Listeria monocytogenes samples confirmed (6.76%. Salmonella spp. was not detected in any of the the samples. The biggest presence was detected for Staphylococcus spp. with 113 positive samples (85.0%. Further testes has shown prevalence of coagulase-positive staphylococci of 73% (97 positive samples. Escherichia coli was confirmed in 57 samples (46.0%. The results from this study clearly indicate that pathogen microorganisms which are important for the human health can be found in the raw cow milk and their presence can be potential hazard for contamination of the milk-processing establishments.

  19. Molecular Methods for Identification of Microorganisms in Traditional Meat Products

    Science.gov (United States)

    Cocolin, Luca; Dolci, Paola; Rantsiou, Kalliopi

    Traditional fermentations are those that have been used for centuries and even pre-date written historical records. Fermentation processes have been developed to upgrade plant and animal materials, to yield a more acceptable food, to add flavor, to prevent the growth of pathogenic and spoilage microorganisms, and to preserve food without refrigeration (Hesseltine & Wang, 1980). Among fermented foods, sausages are the meat products with a longer history and tradition. It is often assumed that sausages were invented by the Sumerians, in what is Iraq today, around 3000 BC. Chinese sausage làcháng, which consisted of goat and lamb meat, was first mentioned in 589 BC. Homer, the poet of The Ancient Greece, mentioned a kind of blood sausage in the Odyssey (book 20, verse 25), and Epicharmus (ca. 550 BC-ca. 460 BC) wrote a comedy entitled “The Sausage”.

  20. Sea Ice Microorganisms: Environmental Constraints and Extracellular Responses

    Directory of Open Access Journals (Sweden)

    Jody W. Deming

    2013-03-01

    Full Text Available Inherent to sea ice, like other high latitude environments, is the strong seasonality driven by changes in insolation throughout the year. Sea-ice organisms are exposed to shifting, sometimes limiting, conditions of temperature and salinity. An array of adaptations to survive these and other challenges has been acquired by those organisms that inhabit the ice. One key adaptive response is the production of extracellular polymeric substances (EPS, which play multiple roles in the entrapment, retention and survival of microorganisms in sea ice. In this concept paper we consider two main areas of sea-ice microbiology: the physico-chemical properties that define sea ice as a microbial habitat, imparting particular advantages and limits; and extracellular responses elicited in microbial inhabitants as they exploit or survive these conditions. Emphasis is placed on protective strategies used in the face of fluctuating and extreme environmental conditions in sea ice. Gaps in knowledge and testable hypotheses are identified for future research.

  1. A New Approach on Sampling Microorganisms from the Lower Stratosphere

    Science.gov (United States)

    Gunawan, B.; Lehnen, J. N.; Prince, J.; Bering, E., III; Rodrigues, D.

    2017-12-01

    University of Houston's Undergraduate Student Instrumentation Project (USIP) astrobiology group will attempt to provide a cross-sectional analysis of microorganisms in the lower stratosphere by collecting living microbial samples using a sterile and lightweight balloon-borne payload. Refer to poster by Dr. Edgar Bering in session ED032. The purpose of this research is two-fold: first, to design a new system that is capable of greater mass air intake, unlike the previous iterations where heavy and power-intensive pumps are used; and second, to provide proof of concept that live samples are accumulated in the upper atmosphere and are viable for extensive studies and consequent examination for their potential weather-altering characteristics. Multiple balloon deployments will be conducted to increase accuracy and to provide larger set of data. This paper will also discuss visual presentation of the payload along with analyzed information of the captured samples. Design details will be presented to NASA investigators for professional studies

  2. Cell surface engineering of industrial microorganisms for biorefining applications.

    Science.gov (United States)

    Tanaka, Tsutomu; Kondo, Akihiko

    2015-11-15

    In order to decrease carbon emissions and negative environmental impacts of various pollutants, biofuel/biochemical production should be promoted for replacing fossil-based industrial processes. Utilization of abundant lignocellulosic biomass as a feedstock has recently become an attractive option. In this review, we focus on recent efforts of cell surface display using industrial microorganisms such as Escherichia coli and yeast. Cell surface display is used primarily for endowing cellulolytic activity on the host cells, and enables direct fermentation to generate useful fuels and chemicals from lignocellulosic biomass. Cell surface display systems are systematically summarized, and the drawbacks/perspectives as well as successful application of surface display for industrial biotechnology are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Evolutionary engineering of industrial microorganisms-strategies and applications.

    Science.gov (United States)

    Zhu, Zhengming; Zhang, Juan; Ji, Xiaomei; Fang, Zhen; Wu, Zhimeng; Chen, Jian; Du, Guocheng

    2018-06-01

    Microbial cells have been widely used in the industry to obtain various biochemical products, and evolutionary engineering is a common method in biological research to improve their traits, such as high environmental tolerance and improvement of product yield. To obtain better integrate functions of microbial cells, evolutionary engineering combined with other biotechnologies have attracted more attention in recent years. Classical laboratory evolution has been proven effective to letting more beneficial mutations occur in different genes but also has some inherent limitations such as a long evolutionary period and uncontrolled mutation frequencies. However, recent studies showed that some new strategies may gradually overcome these limitations. In this review, we summarize the evolutionary strategies commonly used in industrial microorganisms and discuss the combination of evolutionary engineering with other biotechnologies such as systems biology and inverse metabolic engineering. Finally, we prospect the importance and application prospect of evolutionary engineering as a powerful tool especially in optimization of industrial microbial cell factories.

  4. Advancing metabolic engineering through systems biology of industrial microorganisms.

    Science.gov (United States)

    Dai, Zongjie; Nielsen, Jens

    2015-12-01

    Development of sustainable processes to produce bio-based compounds is necessary due to the severe environmental problems caused by the use of fossil resources. Metabolic engineering can facilitate the development of highly efficient cell factories to produce these compounds from renewable resources. The objective of systems biology is to gain a comprehensive and quantitative understanding of living cells and can hereby enhance our ability to characterize and predict cellular behavior. Systems biology of industrial microorganisms is therefore valuable for metabolic engineering. Here we review the application of systems biology tools for the identification of metabolic engineering targets which may lead to reduced development time for efficient cell factories. Finally, we present some perspectives of systems biology for advancing metabolic engineering further. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Invasion by a Japanese marine microorganism in western North America

    Science.gov (United States)

    McGann, M.; Sloan, D.; Cohen, A.N.

    2000-01-01

    The earliest record in western North America of Trochammina hadai Uchio, a benthic foraminifer common in Japanese estuaries, is from sediment collected in Puget Sound in 1971. It was first found in San Francisco Bay in sediment samples taken in 1983, and since 1986 has been collected at 91% of the sampled sites in the Bay, constituting up to 93% of the foraminiferal assemblage at individual sites. The species is also present in recent sediment samples from 12 other sites along the west coast of North America. The evidence indicates that T. hadai is a recent introduction to San Francisco Bay, and is probably also not native to the other North American sites. Trochammina hadai was probably transported from Japan in ships' ballast tanks, in mud associated with anchors, or in sediments associated with oysters imported for mariculture. Its remarkable invasion of San Francisco Bay suggests the potential for massive, rapid invasions by other marine microorganisms.

  6. Molecular Breeding of Advanced Microorganisms for Biofuel Production

    Directory of Open Access Journals (Sweden)

    Hiroshi Sakuragi

    2011-01-01

    Full Text Available Large amounts of fossil fuels are consumed every day in spite of increasing environmental problems. To preserve the environment and construct a sustainable society, the use of biofuels derived from different kinds of biomass is being practiced worldwide. Although bioethanol has been largely produced, it commonly requires food crops such as corn and sugar cane as substrates. To develop a sustainable energy supply, cellulosic biomass should be used for bioethanol production instead of grain biomass. For this purpose, cell surface engineering technology is a very promising method. In biobutanol and biodiesel production, engineered host fermentation has attracted much attention; however, this method has many limitations such as low productivity and low solvent tolerance of microorganisms. Despite these problems, biofuels such as bioethanol, biobutanol, and biodiesel are potential energy sources that can help establish a sustainable society.

  7. Advancing metabolic engineering through systems biology of industrial microorganisms

    DEFF Research Database (Denmark)

    Dai, Zongjie; Nielsen, Jens

    2015-01-01

    resources. The objective of systems biology is to gain a comprehensive and quantitative understanding of living cells and can hereby enhance our ability to characterize and predict cellular behavior. Systems biology of industrial microorganisms is therefore valuable for metabolic engineering. Here we review......Development of sustainable processes to produce bio-based compounds is necessary due to the severe environmental problems caused by the use of fossil resources. Metabolic engineering can facilitate the development of highly efficient cell factories to produce these compounds from renewable...... the application of systems biology tools for the identification of metabolic engineering targets which may lead to reduced development time for efficient cell factories. Finally, we present some perspectives of systems biology for advancing metabolic engineering further....

  8. Isolation of microorganisms from red pepper powder and their radiosensitivity

    International Nuclear Information System (INIS)

    Choi, E.H.; Kim, Y.B.; Lee, S.R.

    1977-01-01

    From samples of red pepper powder sold in Korea were isolated and identified 13 species of molds (Aspergillus amsteodami, Asp. chevalieri, Asp. clavatus, Asp. Flavus, Asp. janus var. effusus, Asp. oryzae, Asp. oryzae var. brevis, Asp. repens, Asp. sydowi, Asp. thomii, Asp. tubingensis, Penicillium thomii, Scopulariopsis brevicaulis) and 5 species of bacteria (Bacillus pumilus, Bac. subtilis, Micrococus luteus, M. varians, Staphylococcus aureus). Radiosensitivity of these microorganisms was examined to give D 10 values of 14-41 krad for molds, 11-24 krad for bacterial vegetative cells and 190-250 krad for bacterial spores. The red pepper powder was contaminated with 2-3x10 2 mold counts/g and 3-6x10 7 bacterial counts/g, which would be sufficiently destroyed by irradiating 200 krad r-rays. (Author)

  9. Inactivation of microorganisms for high pressures in the wine industry

    International Nuclear Information System (INIS)

    Montana B, Jaime Nelson; Ortegon T, Sandra Patricia

    2000-01-01

    In order to evaluate experimentally the capacity of N 2 and CO 2 under pressure to inactivate wild yeasts, which remain in the Puntalarga vineyard grape, musts were exposed to hyperbaric treatment with these gases. At the end of the pascalization (after 2 hours), CO 2 at 15 degrades Celsius under pressures from 1 to 5 MPa, reached high inactivation percentages of yeast cells (> 90%). Contrary to CO 2 treatment the use of N 2 at 15 degrades Celsius at 4 and 10 MPa failed to exert microbicide effect in a same treatment time. While CO 2 gas with high solubility in water has the potential to reduce microbial loads in musts, N 2 gas with low solubility in water have not effect on the survival of the pathogenic microorganisms in these juices

  10. Ocean Tide Loading Computation

    Science.gov (United States)

    Agnew, Duncan Carr

    2005-01-01

    September 15,2003 through May 15,2005 This grant funds the maintenance, updating, and distribution of programs for computing ocean tide loading, to enable the corrections for such loading to be more widely applied in space- geodetic and gravity measurements. These programs, developed under funding from the CDP and DOSE programs, incorporate the most recent global tidal models developed from Topex/Poscidon data, and also local tide models for regions around North America; the design of the algorithm and software makes it straightforward to combine local and global models.

  11. Ocean wave energy conversion

    CERN Document Server

    McCormick, Michael E

    2007-01-01

    This volume will prove of vital interest to those studying the use of renewable resources. Scientists, engineers, and inventors will find it a valuable review of ocean wave mechanics as well as an introduction to wave energy conversion. It presents physical and mathematical descriptions of the nine generic wave energy conversion techniques, along with their uses and performance characteristics.Author Michael E. McCormick is the Corbin A. McNeill Professor of Naval Engineering at the U.S. Naval Academy. In addition to his timely and significant coverage of possible environmental effects associa

  12. Extraordinary proliferation of microorganisms in aposymbiotic pea aphids, Acyrthosiphon pisum.

    Science.gov (United States)

    Nakabachi, Atsushi; Ishikawa, Hajime; Kudo, Toshiaki

    2003-03-01

    Aposymbiotic pea aphids, which were deprived of their intracellular symbiotic bacterium, Buchnera, exhibit growth retardation and no fecundity. High performance liquid chromatographic (HPLC) analysis revealed that these aposymbiotic aphids, when reared on broad bean plants, accumulated a large amount of histamine. To assess the possibility of extraordinary proliferation of microorganisms other than Buchnera, we enumerated eubacteria and fungi in aphids using the real-time quantitative PCR method that targets genes encoding small-subunit rRNAs. The result showed that these microorganisms were extremely abundant in the aposymbiotic aphids reared on plants. Microbial communities in aposymbiotic aphids were further profiled by phylogenetic analysis of small-subunit rDNAs. Of 172 nonchimeric sequences of fungal 18S rDNAs, 138 (80.2%) belonged to the phylum Ascomycota. Among them, 21 clustered within a monophyletic group consisting of insect-pathogenic fungi and yeast-like symbionts of homopteran insects. Thirty-one (18.0%), two (1.2%), and one (0.6%) clones were clustered within the Basidiomycota, Zygomycota, and Oomycota, respectively. Of 167 nonchimeric sequences of eubacterial 16S rDNAs, 84 (50.3%) belonged to the gamma-subdivision of Proteobacteria to which most primary endosymbionts of insects and prolific histamine producers belong. Forty (24.0%), 25 (15.0%), 10 (6.0%), and five (3.0%) clones were clustered within alpha-Proteobacteria, Cytophaga-Flavobacterium-Bacteroides (CFB) group, Actinobacteria, and beta-Proteobacteria, respectively. Three had no phylogenetic association with known taxonomic divisions. None of the sequences studied in this study coincided exactly with those deposited in GenBank.

  13. Sensory Transduction in Microorganisms 2008 Gordon Research Conference (January 2008)

    Energy Technology Data Exchange (ETDEWEB)

    Ann M. Stock

    2009-04-08

    Research into the mechanisms involved in the sensing and responses of microorganisms to changes in their environments is currently very active in a large number of laboratories worldwide. An increasingly wide range of prokaryotic and eukaryotic species are being studied with regard to their sensing of diverse chemical and physical stimuli, including nutrients, toxins, intercellular signaling molecules, redox indicators, light, pressure, magnetic fields, and surface contact, leading to adaptive responses affecting motile behavior, gene expression and/or development. The ease of manipulation of microorganisms has facilitated application of a broad range of techniques that have provided comprehensive descriptions of cellular behavior and its underlying molecular mechanisms. Systems and their molecular components have been probed at levels ranging from the whole organism down to atomic resolution using behavioral analyses; electrophysiology; genetics; molecular biology; biochemical and biophysical characterization; structural biology; single molecule, fluorescence and cryo-electron microscopy; computational modeling; bioinformatics and genomic analyses. Several model systems such as bacterial chemotaxis and motility, fruiting body formation in Myxococcus xanthus, and motility and development in Dictyostelium discoideum have traditionally been a focus of this meeting. By providing a basis for assessment of similarities and differences in mechanisms, understanding of these pathways has advanced the study of many other microbial sensing systems. This conference aims to bring together researchers investigating different prokaryotic and eukaryotic microbial systems using diverse approaches to compare data, share methodologies and ideas, and seek to understand the fundamental principles underlying sensory responses. Topic areas include: (1) Receptor Sensing and Signaling; (2) Intracellular Signaling (two-component, c-di-GMP, c-AMP, etc.); (3) Intracellular Localization and

  14. Production of bioplastics and hydrogen gas by photosynthetic microorganisms

    Science.gov (United States)

    Yasuo, Asada; Masato, Miyake; Jun, Miyake

    1998-03-01

    Our efforts have been aimed at the technological basis of photosynthetic-microbial production of materials and an energy carrier. We report here accumulation of poly-(3-hydroxybutyrate) (PHB), a raw material of biodegradable plastics and for production of hydrogen gas, and a renewable energy carrier by photosynthetic microorganisms (tentatively defined as cyanobacteria plus photosynthetic bateria, in this report). A thermophilic cyanobacterium, Synechococcus sp. MA19 that accumulates PHB at more than 20% of cell dry wt under nitrogen-starved conditions was isolated and microbiologically identified. The mechanism of PHB accumulation was studied. A mesophilic Synechococcus PCC7942 was transformed with the genes encoding PHB-synthesizing enzymes from Alcaligenes eutrophus. The transformant accumulated PHB under nitrogen-starved conditions. The optimal conditions for PHB accumulation by a photosynthetic bacterium grown on acetate were studied. Hydrogen production by photosynthetic microorganisms was studied. Cyanobacteria can produce hydrogen gas by nitrogenase or hydrogenase. Hydrogen production mediated by native hydrogenase in cyanobacteria was revealed to be in the dark anaerobic degradation of intracellular glycogen. A new system for light-dependent hydrogen production was targeted. In vitro and in vivo coupling of cyanobacterial ferredoxin with a heterologous hydrogenase was shown to produce hydrogen under light conditions. A trial for genetic trasformation of Synechococcus PCC7942 with the hydrogenase gene from Clostridium pasteurianum is going on. The strong hydrogen producers among photosynthetic bacteria were isolated and characterized. Co-culture of Rhodobacter and Clostriumdium was applied to produce hydrogen from glucose. Conversely in the case of cyanobacteria, genetic regulation of photosynthetic proteins was intended to improve conversion efficiency in hydrogen production by the photosynthetic bacterium, Rhodobacter sphaeroides RV. A mutant acquired by

  15. The Effect of High Hydrostatic Pressure on Microorganisms in Food Preservation

    OpenAIRE

    M. Arici

    2006-01-01

    High hydrostatic pressure is a new food preservation technology known for its capacity to inactivate spoilage and pathogenic microorganisms. High-pressure treatments are receiving a great deal of attention for the inactivation of microorganisms in food processing, pressure instead of temperature is used as stabilizing factor. High hydrostatic pressure treatment is the most studied alternative process, many works reported successful results in inactivating a wide range of microorganisms under ...

  16. Interactions Between Beneficial and Harmful Microorganisms: From the Composting Process to Compost Application

    OpenAIRE

    Fuchs, Jacques G.

    2010-01-01

    Numerous microorganisms are involved in the composting process, but their precise roles are often unknown. Compost microorganisms are influenced by the composition of the substrate and by the temperature in the compost pile. In addition, different microorganisms also influence each other, e.g. through competition. In the first phase of composting, microbial activity increase drastically, leading to a rise in temperature. The initial bacterial dominance is replaced by a fungal one during compo...

  17. Root Canal Microorganism Profiles on Upper Anterior Teeth of Apical Periodontitis

    OpenAIRE

    Riuwpassa, E. Irene

    2013-01-01

    Microorganisms are the main causative agents on the development of apical periodontitis. Microorganisms infecting the root canal system are colonized in communities as biofilm. These bacterial communities show distinct pattern related to the different forms of apical periodontitis which are determined by species richness and abundance.this study is aimed to examine the root canal microorganisms on upper anterior teeth of asymptomatic apical periodontitis and chronic apical abscess. Samples we...

  18. Root Canal Microorganisms Profiles of Upper Anterior Teeth with Periapical Lesion

    OpenAIRE

    Maria Tanumiharja; Irene E. Riewpassa; Mansjur Nasir; Burhanuddin D. Pasiga

    2014-01-01

    Microorganisms are the main causative agents on the development of apical periodontitis. Microorganisms infecting the root canal system are colonized in communities as biofilm. These bacterial communities show distinct pattern related to the different forms of apical periodontitis which are determined by species richness and abundance. Objective: This study is aimed to examine the root canal microorganisms on upper anterior teeth of asymptomatic apical periodontitis and chronic apical abscess...

  19. ROOT CANAL MICROORGANISMS PROFILES O F UPPER ANTERIOR TEETH WITH APICAL PERIODONTITIS

    OpenAIRE

    Tanumihardja, Maria; Riewpassa, Irene E; Mansjurnasir; Burhanuddin, DP

    2013-01-01

    Microorganisms are the main causative agents on the development of apical periodontitis. Microorganisms infecting the root canal system are colonized in communities as biofilm. These bacterial communities show distinct pattern related to the different forms of apical periodontitis which are determined by species richness and abundance. This study is aimed to examine the root canal microorganisms on upper anterior teeth of asymptomatic apical periodontitis and ch ronic api...

  20. Monitoring of ocean storage projects

    Energy Technology Data Exchange (ETDEWEB)

    Caldeira, K. [Energy and Environment Directorate, Lawrence Livermore National Laboratory, Livermore, CA (United States)

    2003-02-01

    It has been proposed that atmospheric CO2 accumulation could be slowed by capture of CO2 from point sources and subsequent storage of that CO2 in the ocean. If applied, such sequestration efforts would need to be monitored for compliance, effectiveness, and unintended consequences. Aboveground inspection and monitoring of facilities and practices, combined with ocean observations, could assure compliance with ocean sequestration guidelines and regulations. Ocean observations could be made using a variety of sensors mounted on moorings or underwater gliders. Long-term effectiveness and leakage to the atmosphere must be estimated from models, since on large spatial scales it will be impossible to observationally distinguish carbon stored by a project from variable concentrations of background carbon. Furthermore, the ocean naturally would absorb roughly 80% of fossil fuel CO2 released to the atmosphere within a millennium. This means that most of the CO2 sequestered in the ocean that leaks out to the atmosphere will be reabsorbed by the ocean. However, there is no observational way to distinguish remaining carbon from reabsorbed carbon. The science of monitoring unintended consequences in the deep ocean interior is at a primitive state. Little is understood about ecosystems of the deep ocean interior; and even less is understood about how those ecosystems would respond to added CO2. High priority research objectives should be (1) to improve our understanding of the natural ecosystems of the deep ocean, and (2) to improve our understanding of the response of these ecosystems to increased oceanic CO2 concentrations and decreased ocean pH.