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| Registros recuperados: 341 | |
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| Morita, R; Jones, R. |
| The nitrifying bacteria were found to survive 24 weeks in the absence of ammonium without decreasing their number of cell size. Because H sub(2), CO, and CH sub(4) are present in the marine environment, these substrates were investigated as a possible source of the energy of maintenance for the nitrifying bacteria. super(14)CO and super(14)CH sub(4) were found to be oxidized by the nitrifiers. N-serve was found to inhibit the oxidation of CO. Using the nitrifiers' ability to oxide CO, a method for the determination of the nitrification rate was developed. The ability of nitrifiers to oxidize CO may play a significant role in the cycling of CO sub(2) in the marine environment. Whether CO and CH sub(4) oxidation play a role in the survival of nitrifiers in... |
| Tipo: Text |
Palavras-chave: Methane; Carbon dioxide; Survival; Bacteria; Nitrification; Nitrogen cycle; Oxidation; Carbon cycle; Biogeochemistry; Metabolism. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-975.pdf |
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| Okpokwasili, G; Somerville, C; Grimes, D; Colwell, R. |
| A differential, phenanthrene-enrichment agar plating technique was used to isolate phenanthrene-degrading bacteria from phenanthrene-enriched Chesapeake Bay sediment. One of the isolates, a yellow pigmented, slime-producing, Gram-negative rod identified as Flavobacterium sp. has been studied in detail. It has been found to carry a single plasmid with a mass of about 34 megadaltons. Results of hydrocarbon adherence tests showed that the organism adhered only minimally to n-octane and n-hexadecane, but emulsified cyclohexylbenzene and 1,2,3,4,-tetrahydronaphthalene (tetralin). Curing of the plasmid with 3 mu g/ml novobiocin resulted in loss of phenanthrene clearing ability. Ability to degrade phenanthrene was confirmed using super(14)C-labeled phenanthrene. |
| Tipo: Text |
Palavras-chave: Flavobacterium; Microbiological culture; Culture media; Bacteria; Sediment pollution; Biodegradation; Bacteria collecting devices. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-1014.pdf |
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| Blanchard, Gérard F; Sauriau, Pg; Cariou-le Gall, Valerie; Gouleau, D; Garet, Mj; Olivier, F. |
| Resuspension of the top few sediment layers of tidal mud flats is known to enhance planktonic biomass of microbiota (benthic diatoms and bacteria). This process is mainly controlled by tidal shear stress and cohesiveness of mud, and is also influenced by bioturbation activities. Laboratory experiments in a race track flume were performed to test the interactive effects of these factors on both the critical entrainment and resuspension kinetics of microbiota from silt-clay sediments from the Marennes-Oleron Bay, France. The marine snail Hydrobia ulvae was used to mimic surface bioturbation activities. As expected, the kinetics of microbial resuspension versus shear stress were largely controlled by the cohesiveness of silt-clay sediments. However, our... |
| Tipo: Text |
Palavras-chave: Microphytobenthos; Bacteria; Resuspension; Bioturbation; Hydrobia ulvae; Shear velocity; Sediment cohesiveness; Flume experiment. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00337/44789/44480.pdf |
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| L' Haridon, S; Reysenbach, A.l.; Tindall, B. J.; Schonheit, P; Banta, A; Johnsen, U; Schumann, P; Gambacorta, A; Stackebrandt, E; Jeanthon, C. |
| Three thermophilic, anaerobic, strictly chemolithoautotrophic, sulphur- and/or thiosulphate-reducing bacteria, designated SL17(T), SL19(T) and SL22(T), were isolated from deep-sea hydrothermal samples collected at 13 degrees N (East Pacific Rise), Guaymas Basin (Gulf of California) and 23 degrees N (Mid-Atlantic Ridge), respectively. These strains differed in their morphology, temperature range and optimum for growth, energy substrates and 16S rRNA gene sequences. The G + C content of the genomic DNA was 41 mol% (SL22(T)), 42 mol% (SL17(T)) and 46 mol% (SL19(T)). Comparative analysis of phenotypic and phylogenetic traits indicated that strains SL17(T) and SL22(T) represented two novel species of the genus Desulfurobacterium and that strain SL19(T) should... |
| Tipo: Text |
Palavras-chave: Hydrothermal environment; Phylogeny; Thermophiles; Bacteria. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2174.pdf |
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| Goutx, H; Berland, B; Leveau, M; Bertrand, J. |
| The effects of products resulting from petroleum biodegradation in continuous culture, have been studied on the growth of two marine algae. Sugars, lipids and amino acids are the main components resulting from petroleum degradation in the bacteria used medium. Their concentrations are respectively 600 mg.l super(-1), 46 mg.l super(-1) and 74.2 mu M.l super(-1). The algae growth is inhibited when products are enough concentrated; it is stimulated by low concentration. Among these products, lipids are more toxic than others. The two species show different sensitivity towards the used medium. Prorocentrum micans growth is more inhibited than that of Phaeodactylum tricornutum . |
| Tipo: Text |
Palavras-chave: Bacteria; Phytoplankton; Toxicity; Oil pollution; Crude oil; Biodegradation. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-1017.pdf |
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| Villeger, Sebastien; Fouilland, Eric; Argenty, Jeremy; Bouvier, Corinne; Carre, Claire; Bouvier, Thierry. |
| The productivity of most marine ecosystems is limited by the availability of dissolved nitrogen (N) and phosphorus (P). Nutrient recycling is therefore a key process for ecosystem functioning. Fish recycle nutrients through the excretion of ammonia and phosphate and can influence the abundance and community structure of primary producers such as phytoplankton. However, the effect of fish on other plankton compartments, and whether all fish species have similar effects, is largely unknown. We used a tank experiment to test how 2 Mediterranean fish species, gilthead seabream Sparus aurata and golden mullet Chelon auratus, with distinctly different N and P excretion rates, can affect the abundance and community structure of 3 plankton compartments:... |
| Tipo: Text |
Palavras-chave: Marine fish; Nutrient excretion; Protozooplankton; Phytoplankton; Bacteria. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00584/69659/67585.pdf |
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| Battersby, N; Stewart, D; Sharma, A. |
| Chemical additives are used extensively in the offshore oil industry. For secondary oil recovery, the biopolymer xanthan has been recommended as a viscosifying agent but its use may provoke microbial problems. The effect of adding xanthan to marine sediments on the growth and metabolic activity of sulphate-reducing bacteria (SRB) was studied. In all instances, its addition resulted in an increasing in SRB numbers of up to 250-fold. This was accompanied by a marked increase in the electron transport activity of the sediments when these were incubated under either aerobic or anaerobic conditions. The products formed as a result of the biodegradation of the polymer by indigenous heterotrophic bacteria in these sediments appear to have acted as suitable... |
| Tipo: Text |
Palavras-chave: Bacteria; Growth; Additives; Pollution effects; Oil recovery; Biodegradation; Polymers; Sediment pollution; Sulfate reduction. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-1015.pdf |
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| Riou, V.; Halary, S.; Duperron, S.; Bouillon, S.; Elskens, M.; Bettencourt, R.; Santos, R. S.; Dehairs, F.; Colaco, A.. |
| High densities of mussels of the genus Bathymodiolus are present at hydrothermal vents of the Mid-Atlantic Ridge. It was previously proposed that the chemistry at vent sites would affect their sulphide- and methane-oxidizing endosymbionts' abundance. In this study, we confirmed the latter assumption using fluorescence in situ hybridization on Bathymodiolus azoricus specimens maintained in a controlled laboratory environment at atmospheric pressure with one, both or none of the chemical substrates. A high level of symbiosis plasticity was observed, methane-oxidizers occupying between 4 and 39% of total bacterial area and both symbionts developing according to the presence or absence of their substrates. Using (HCO3-)-C-13 in the presence of sulphide, or... |
| Tipo: Text |
Palavras-chave: Mid-atlantic ridge; Hydrocarbon-seep mussel; Deep-sea mussels; Hydrothermal-vent; Puteoserpentis bivalvia; Mytilidae; Methane; Endosymbionts; Bacteria; Metabolism. |
| Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00207/31865/30271.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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| Malfatti, Matilde Clarissa; Henneke, Ghislaine; Balachander, Sathya; Koh, Kyung Duk; Newnam, Gary; Uehara, Ryo; Crouch, Robert J.; Storici, Francesca; Tell, Gianluca. |
| The presence of ribonucleoside monophosphates (rNMPs) in nuclear DNA decreases genome stability. To ensure survival despite rNMP insertions, cells have evolved a complex network of DNA repair mechanisms, in which the ribonucleotide excision repair pathway, initiated by type 2 ribonuclease H (RNase HII/2), plays a major role. We recently demonstrated that eukaryotic RNase H2 cannot repair damaged, that is, ribose monophosphate abasic (both apurinic or apyrimidinic) site (rAP) or oxidized rNMP embedded in DNA. Currently, it remains unclear why RNase H2 is unable to repair these modified nucleic acids having either only a sugar moiety or an oxidized base. Here, we compared the endoribonuclease specificity of the RNase HII enzymes from the archaeon Pyrococcus... |
| Tipo: Text |
Palavras-chave: Ribonuclease; Bacteria; Escherichia coli (E coli); Archaea; Oxidative stress; Abasic-ribose; Oxidized-ribonucleotides; Pyrococcus abyssi; Type 2 RNase H. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00506/61796/65801.pdf |
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| Lossouarn, Julien; Dupont, Samuel; Gorlas, Aurore; Mercier, Coraline; Bienvenu, Nadege; Marguet, Evelyne; Forterre, Patrick; Geslin, Claire. |
| Mobile genetic elements (MGEs) such as viruses, plasmids, vesicles, gene transfer agents (GTAs), transposons and transpovirions, which collectively represent the mobilome, interact with cellular organisms from all three domains of life, including those thriving in the most extreme environments. While efforts have been made to better understand deep-sea vent microbial ecology, our knowledge of the mobilome associated with prokaryotes inhabiting deep-sea hydrothermal vents remains limited. Here we focus on the abyssal mobilome by reviewing accumulating data on viruses, plasmids and vesicles associated with thermophilic and hyperthermophilic Bacteria and Archaea present in deep-sea hydrothermal vents. |
| Tipo: Text |
Palavras-chave: Deep-sea hydrothermal vent; Bacteria; Archaea; (Hyper-)thermophiles; Mobilome. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00260/37145/36731.pdf |
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| Amiraux, Rémi; Burot, Christopher; Bonin, Patricia; Massé, Guillaume; Guasco, Sophie; Babin, Marcel; Vaultier, Frédéric; Rontani, Jean-françois. |
| During sea-ice melt in the Arctic, primary production by sympagic (sea-ice) algae can be exported efficiently to the seabed if sinking rates are rapid and activities of associated heterotrophic bacteria are limited. Salinity stress due to melting ice has been suggested to account for such low bacterial activity. We further tested this hypothesis by analyzing samples of sea ice and sinking particles collected from May 18 to June 29, 2016, in western Baffin Bay as part of the Green Edge project. We applied a method not previously used in polar regions—quantitative PCR coupled to the propidium monoazide DNA-binding method—to evaluate the viability of bacteria associated with sympagic and sinking algae. We also measured cis-trans isomerase activity, known to... |
| Tipo: Text |
Palavras-chave: Bacteria; Sea ice; Sympagic algae; Ice biota; Viability; Stress factors; Salinity; Bactericidal free fatty acids; Carbon export. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00681/79329/81840.pdf |
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| Herbert, R. |
| Seasonal data and depth profiles using super(15)N-labelled NO sub(3)u- show that denitrification (77-90% of NO sub(3)u- respired) rather than NO sub(3)u- dissimilation to NH sub(4)u+ was the principal route of nitrate reduction in Kingoodie Bay sediments. Populations of both groups of NO sub(3)u- reducing bacteria were highest in the 0-20 mm horizon in those sediments where highest rates of NO sub(3)u- respiration were recorded (28.56 mu g N.d super(-1) dry wt. sediment super(-1)). Autotrophic nitrification rates shared a marked seasonality with highest rates (0.92 mu g N.d super(-1).g dry wt. sediment super(-1)) occurring during the summer. Maximum populations of autotrophic nitrifying bacteria were also found in the 0-20 mm sediment horizon and these... |
| Tipo: Text |
Palavras-chave: Seasonal variations; Bacteria; Estuaries; Sediment chemistry; Biogeochemistry; Ammonia; Nitrates; Nitrogen cycle. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-971.pdf |
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| Fontanier, Christophe; Koho, K. A.; Goni-urriza, M. S.; Deflandre, Bruno; Galaup, S.; Ivanovsky, A.; Gayet, Nicolas; Dennielou, Bernard; Gremare, Antoine; Bichon, S.; Gassie, C.; Anschutz, P.; Duran, R.; Reichart, G. J.. |
| We present ecological and isotopic (δ18O and δ13C) data on benthic foraminifera sampled from 4 deep-sea stations in a pockmark field from the deep-water Niger delta (Gulf of Guinea, Equatorial Atlantic Ocean). In addition, a series of sedimentological and (bio)geochemical data are shown to back up foraminiferal observations. All stations are located within 1.2 km of each other, so prevailing oceanographic conditions can be assumed to be similar at each site. Two of the sites (GMMC-01 and GMMC-02) are located in a pockmark (named “pockmark A”) where current methane seepages were recorded by ROV observations. A third station (GMMC-03) is located in the topographic depression interpreted as a collapsed pockmark (named “pockmark B”). The fourth site (GMMC-04)... |
| Tipo: Text |
Palavras-chave: Niger delta; Hydrate pockmark; Foraminifera; Stable isotopes; Bacteria. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00211/32194/30628.pdf |
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| Registros recuperados: 341 | |
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