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Registros recuperados: 91 | |
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Takai, Ken; Miyazaki, Masayuki; Hirayama, Hisako; Nakagawa, Satoshi; Querellou, Joel; Godfroy, Anne. |
P>Two novel, thermophilic piezophiles, capable of chemolithoautotrophic growth, are successfully cultivated and isolated from a black smoker chimney at the TAG field (Mid Atlantic Ridge: MAR) by using a piezophilic cultivation technique. Both strains (strains 106 and 108) represent dominant cultivated populations of the microbial communities in the chimney surface habitat. Strain 106 represents typically thin, long spiral cells under the piezophilic growth condition but short bent cells under the non-piezophilic condition. It is a strictly chemolithoautotrophic gammaproteobacterium using reduced sulfur compounds as the electron donors, and nitrate and O-2 as the electron acceptors. Based on the 16S rRNA gene sequence, strain 106 would represent a novel... |
Tipo: Text |
Palavras-chave: Sp. nov.; Ecological signifiance; Hydrostatic pressure; Subsurface biosphere; Base composition; High temperature; Membrane lipids; Gen. nov.; Microorganisms; Diversity. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6652.pdf |
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Slobodkina, G. B.; Kolganova, T. V.; Querellou, Joel; Bonch-osmolovskaya, E. A.; Slobodkin, A. I.. |
A hyperthermophilic, anaerobic, dissimilatory Fe(III)-reducing, facultatively chemolithoautotrophic archaeon (strain SBH6(T)) was isolated from a hydrothermal sample collected from the deepest of the known World Ocean hydrothermal fields, Ashadze field (12 degrees 58' 21 '' N 44 degrees 51' 47 '' W) on the Mid-Atlantic Ridge, at a depth of 4100 m. The strain was enriched using acetate as the electron donor and Fe(III) oxide as the electron acceptor. Cells of strain SBH6(T) were irregular cocci, 0.3-0.5 mu m in diameter. The temperature range for growth was 50-85 degrees C, with an optimum at 81 degrees C. The pH range for growth was 5.0-7.5, with an optimum at pH 6.8. Growth of SBH6(T) was observed at NaCl concentrations ranging from 1 to 6 % (w/v) with an... |
Tipo: Text |
Palavras-chave: Dissimilatory reduction; Microorganisms; Gradient. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6977.pdf |
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Pommepuy, Monique; Hervio Heath, Dominique; Caprais, Marie-paule; Gourmelon, Michele; Le Saux, Jean-claude; Le Guyader, Soizick. |
Introduction : "The occurrence of pathogenic microorganisms in seawater or in shellfish could exist anytime sewage from human or animal origin would be discharged to the coast" (Metcalf, 1982). According to the diseases occurring in the human population or in animals, pathogens might be present in recreational waters or in shellfish. Thus, the presence of human enteric viruses (norovirus, astrovirus, rotavirus, hepatitisAvirus (HAV)) and pathogenic bacteria (Salmonella, Listeria monocytogenes, Shiga-toxin-producing Escherichia coli (STEC), Vibrio cholerae, Vibrio parahaemolyticus, etc.) has been reported in coastal areas for a long time (Colwell, 1978; Metcalf, 1978; Melnick et al., 1979; Grimes, 1991; Bosch et al., 2001;Kong et al., 2002). These... |
Tipo: Text |
Palavras-chave: Estimating model; Infection dose; Microorganisms; STEC; Bacteria; Virus; Fecal contamination; Pathogenic agent; Marine sediment; Estuarine water; Coastal area; Marine water. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1207.pdf |
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Michoud, Grégoire. |
Since the discovery of hydrothermal vents in 1977, a small number of studies have allowed the isolation and characterization of microorganisms that can withstand high pressures and temperatures. Among these, Pyrococcus yayanosii, a hyperthermophilic archaea of the order Thermococcales, came from the Ashadze site (Mid-Atlantic Ridge) at 4100 m depth. This species represents the first organism both hyperthermophilic and strict piezophilic described to date. It cannot divide at pressures below 20 MPa and its optimal growth pressure is 52 MPa. In order to study the mechanisms used by this species to grow under high pressures, transcriptomics (DNA chips) and proteomics (LC-MS/MS) experiments have been carried out at different pressures, notably sub- and... |
Tipo: Text |
Palavras-chave: Micro-organismes; Pression; Piézophile extrême; Hyperthermophile; Microorganisms; Hyperthermophilic. |
Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00609/72138/70890.pdf |
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Portier, R; Meyers, S. |
The environmental effect and fate of several agricultural and industrial source toxicants were evaluated in controlled laboratory microcosm systems in the presence of the aminopolysaccharide polymer, chitin. Toxicants examined included methyl parathion, phenol, pentachlorophenol, 2,4 dichlorophenol, 1,2 dichloroethane and Kepone. Microcosm operating parameters, including pH/Eh, salinity, temperature, flow rate and sediment/water interface conditions, were based on comparable in situ measurements. Fate analysis predictions were based on mineralization of the parent toxicant compound as measured by chromatographic analysis or super(14)CO sub(2) expiration. Chitin, amended to continuous flow microcosms, promoted either cometabolic or cooxidative... |
Tipo: Text |
Palavras-chave: Controlled conditions; Chemical pollutants; Industrial wastes; Pesticides; Metabolism; Food webs; Biodegradation; Ecosystems; Microorganisms; Environmental effects; Brackishwater pollution; Estuaries; Toxicants; Chitin. |
Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-1011.pdf |
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Herndl, G; Velimirov, B. |
Bacterial density of the coelenteric fluid (CF) of some anthozoan species was determined in situ and under laboratory conditions. In all species examined bacterial density of the CF was higher in the gastral cavity than in ambient ranging from 10 super(5) up to 5 x 10 super(6) cells. ml super(-1). Incubation experiments with the CF indicate that a bacterial population within the coelenteron is efficiently controlled by the CF, favoring bacterial growth if bacterial densities are low in the CF and showing clearance activity at high bacterial densities. Feeding of pre-starved anthozoans caused a rapid response of coelenteric rod-shaped bacteria. Evidence is presented that coelenteric bacteria are digested periodically although they contribute 1% to the... |
Tipo: Text |
Palavras-chave: Anthozoa; Coelomic fluids; Bacteria; Microorganisms; Interspecific relationships; Metabolism; Nutrition. |
Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-989.pdf |
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Reichardt, W. |
The predominantly anoxic, sulfide-rich sandy sediment of a shallow lagoon at Kiel Fjord was densely inhabited by the polychaete worm Nereis diversicolor (280 cm super(3) m super(-2) of biomass volume). Burrow walls which contrasted by their brown coloration of at least 1.5 mm thickness with the bulk of the reduced black sediment, made up for 6% of the total volume of the 10 cm cores investigated. Only the uppermost mm of the internal surface layer contained detectable O sub(2). As a result of the build up of internal redox gradients, CO sub(2) dark fixation was activated in the burrow walls (by a factor of approximately equals 2). Assays of ribulose-biphosphate carboxylase activities and viable counts of potentially chemoautotrophic bacteria in different... |
Tipo: Text |
Palavras-chave: Nereis diversicolor; Polychaeta; Bacteria; Microorganisms; Carbon cycle; Tube dwellers; Carbon fixation; Burrows; Bioturbation; Sediments. |
Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-990.pdf |
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Dupuy, Christine; Mallet, Clarisse; Guizien, Katell; Montanie, Helene; Breret, Martine; Mornet, Francoise; Fontaine, Camille; Nerot, Caroline; Orvain, Francis. |
Resuspension thresholds in terms of friction velocity were experimentally quantified for the prokaryotes, protists and for the first time, viruses of intertidal mudflat biofilms. Differences in resuspension thresholds could be related to the type, behaviour and size of microorganisms and their association with particles. Free microorganisms (viruses, bacteria and some nanoflagellates) were resuspended by weak flow at friction velocities lower than 2 cm s- 1. Chlorophyll a, some nanoflagellates and attached bacteria were resuspended together with the bed’s muddy sediment, which required friction velocities larger than 3 cm s- 1. Diatoms smaller than 60 μm were resuspended at velocities between 3 and 5 cm s- 1, while those larger than 60 μm were resuspended... |
Tipo: Text |
Palavras-chave: Viruses; Microorganisms; Resuspension; Benthic-pelagic coupling; Spatial distribution; Mudflat. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00168/27922/26196.pdf |
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Perestrelo,M. F.; Norberg,A. N.; Guerra-Sanches,F.; Torres,A. C.; Pile,E.. |
Water used in hydrotherapy units of Nova Iguaçu and Nilópolis, Rio de Janeiro State, Brazil, was microbiologically analyzed. Thirty samples (5ml each) were weekly collected from September 2001 to June 2002 before the beginning and after the end of activities in the units. For analysis, routine techniques were used, which showed the presence of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella spp, Candida spp, Penicillium spp, Epidermophyton spp, Aspergillus fumigatus, Aspergillus niger, Aspergillus spp, Cephalosporium spp, Cladosporium spp, Trichophyton rubrum, and Trichophyton spp. Results indicated a need for improving hygienic conditions, suggesting that water might be a contamination source in the evaluated units. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hydrotherapy; Water; Microorganisms; Bacteria; Fungi. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992006000300006 |
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Registros recuperados: 91 | |
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