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Registros recuperados: 341 | |
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Joux, Fabien; Agogue, Helene; Obernosterer, Ingrid; Dupuy, Christine; Reinthaler, Thomas; Herndl, Gerhard J.; Lebaron, Philippe. |
In an attempt to compare the microbial community structure between the sea surface microlayer (SML) and subsurface waters (SSW), we determined the enrichment factors (EF: the ratio of abundance or activity in the SML to abundance or activity in SSW) of 13 biological parameters. Samples were taken at 2 contrasting coastal sites in the Mediterranean Sea, corresponding to a high (Barcelona, Spain) and low (Banyuls-sur-Mer, France) urbanized area. Principal component analysis showed that temporal variability was much higher at Barcelona than at Banyuls, and that the characteristics of the SML and SSW samples were more closely related at Barcelona. At both sites, the SML was weakly enriched in heterotrophic bacteria (on average 1.1-fold), Synechococcus spp. (on... |
Tipo: Text |
Palavras-chave: Sea surface microlayer; Enrichment factor; Microbial structure; Virus-like particles; Bacteria; Microalgae; Nanoflagellates. |
Ano: 2006 |
URL: https://archimer.ifremer.fr/doc/00243/35434/33961.pdf |
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Brisbarre, Nadège; Fardeau, Marie-laure; Cueff, Valerie; Cayol, Jean-luc; Barbier, Georges; Cilia, Valérie; Ravot, Gilles; Thomas, Pierre; Garcia, Jean-louis; Ollivier, Bernard. |
A strictly anaerobic, slightly halophilic and moderately thermophilic, sporulating rod designated strain DVird3(T) was isolated from deep-sea hydrothermal vent samples collected at a depth of approximately 800 m on the Atlantic Ocean Ridge. Strain DVird3(T) possessed a few laterally inserted flagella, had a DNA G+C content of 33.1 mol% and grew optimally at pH 6.6 and at 45 degreesC. Growth was observed at temperatures between 20 and 58 degreesC and at pH values between 5.8 and 8.2. The optimum NaCl concentration for growth was 3% sea salt (30 g l(-1)); no growth was observed in the presence of 15 or 60 g sea salt l(-1). Strain DVird3(T) is heterotrophic and utilizes some sugars and various single amino acids. Acetate was the main fatty acid detected from... |
Tipo: Text |
Palavras-chave: Phylogeny; Thermophile; Bacteria; Deep sea hydrothermal vent. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/publication-588.pdf |
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Patel, Vilas; Chevignon, Germain; Manzano-marin, Alejandro; Brandt, Jayce W.; Strand, Michael R.; Russell, Jacob A.; Oliver, Kerry M.. |
Heritable symbionts are common in terrestrial arthropods and often provide beneficial services to hosts. Unlike obligate, nutritional symbionts that largely persist under strict host control within specialized host cells, heritable facultative symbionts exhibit large variation in within-host lifestyles and services rendered with many retaining the capacity to transition among roles. One enigmatic symbiont, Candidatus Fukatsuia symbiotica, frequently infects aphids with reported roles ranging from pathogen, defensive symbiont, mutualism exploiter, and nutritional co-obligate symbiont. Here, we used an in vitro culture-assisted protocol to sequence the genome of a facultative strain of Fukatsuia from pea aphids (Acyrthosiphon pisum). Phylogenetic and genomic... |
Tipo: Text |
Palavras-chave: Heritable symbiont; Bacteria; Comparative genomics; Insect; Evolutionary transition. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00635/74663/74594.pdf |
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Joffraud, Jean-jacques; Leroi, Francoise; Roy, Caroline; Berdague, J. |
This study investigated the volatile compounds produced by bacteria belonging to nine different bacterial groups: Lactobacillus sake, L. farciminis, L. alimentarius. Carnobacterium piscicola, Aeromonas sp., Shewanella putefaciens. Brochothrix thermosphacta, Photobacterium phosphoreum and Enterobacteriaceae isolated from cold-smoked salmon. Each bacterial group was represented by several strains. In addition, combinations of the groups were examined as well. Sterile blocks of cold-smoked salmon were inoculated, vacuum-packed and stored at 6 degreesC. After 40 days of storage at 6 degreesC, aerobic viable count and pH were recorded, the volatile fraction of the samples was analysed by gas chromatography-mass spectrometry (GC-MS). and spoilage was assessed by... |
Tipo: Text |
Palavras-chave: Volatile compounds; Bacteria; Spoilage; Cold smoked salmon. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-492.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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Gatesoupe, Fj. |
The proportion of vibrio E, dominant in healthy turbot larvae, was artificially increased in the rotifer enrichment medium. The maid effect of this vibrio enrichment was to improve the resistance of larval turbot challenged with a pathogenic strain of Vibrio splendidus, vibrio P. The improvement of the survival rates was significant with 1.5 x 10(6) CFU of vibrio E added per mi of enrichment medium, and it was still maximum at the hi hest dose tested (5 x 10(7) CFU.ml(-1); 80 +/- 2% of survivors after 48 h of challenge, versus 50 +/- 2 % for the control group). Further in vitro characterisation showed that vibrio E was able to grow in the presence of the chelating agents EDDHA and EDTA, while producing siderophore, as revealed by chrome azurol S dyeing.... |
Tipo: Text |
Palavras-chave: Bacteria; Pathogenic Vibrio; Probiotic Vibrio; Experimental infection; Siderophore; Turbot; Larva. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00065/17671/15199.pdf |
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Stohr, Valerie; Joffraud, Jean-jacques; Cardinal, Mireille; Leroi, Francoise. |
Off-odours/flavours associated with cold-smoked salmon spoilage are due to the activity of microflora. This study evaluated the spoilage potential of nine bacterial groups (Shewanella putrefaciens, Brochothrix thermosphacta, Aeromonas spp., Lactobacillus alimentarius, Lactobacillus sake,Lactobacillus farciminis, Carnobacterium piscicola, Photobacterium phosphoreum and Serratia liquefaciens) isolated from cold-smoked salmon. Five different isolates from each group were inoculated into sterile cold-smoked salmon blocks, and chemical and sensory changes were studied after five weeks of storage in vacuum packs at 6 degreesC. Bacterial growth was monitored weekly during the storage period. A sensory profile was assigned to each group, Principal component... |
Tipo: Text |
Palavras-chave: Sensory analysis; Spoilage potential; Bacteria; Cold smoked salmon. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-578.pdf |
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Pascal, P.y.; Dupuy, C; Richard, P; Rzeznik-orignac, J; Niquil, Nathalie. |
The fate of the benthic bacterial biomass is a topic of major importance in understanding how softbottom environments function. Because of their high abundance, production and nutritional value, benthic bacteria may constitute an important food resource for benthic fauna. The trophic role of bacteria for a nematode community on the Brouage mudflat (Marennes-Ole´ron-France), dominated by three species: Chromadora macrolaima (64% of the abundance), Daptonema oxycerca (15%) and Ptycholaimellus jacobi (8%), was determined in grazing experiments using 15N pre-enriched bacteria. On intertidal flats, seasonal, tidal and circadian cycles induce strong variations in environmental conditions. Grazing experiments were performed in order to measure the effects of... |
Tipo: Text |
Palavras-chave: Mudflat; Environmental factor; Grazing; Bacteria; Nematode. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4295.pdf |
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Elmnasser, Noura; Ritz, Magali; Leroi, Francoise; Orange, Nicole; Bakhrouf, Amina; Federighi, Michel. |
Pulsed light is a new method intended for the decontamination of food surfaces using short, high frequency pulses of an intense broad spectrum. The effects of broad spectrum pulsed light on the survival of Listeria monocytogenes Scott A, Listeria monocytogenes CNL, Pseudomonas fluorescens MF37 and Photobacterium phosphoreum SF680 populations on agar and in a liquid medium were investigated during this study. The sterilisation system generated 1.5 J cm(-2) per pulse with eight lamps for 300 mu s. In the case of surface-seeded cells, a 7.8, 8.14 and > 7.14 log reduction was obtained for L. monocytogenes, Ps. fluorescens MF37 and Ph. phosphoreum, respectively, after a single pulse of treatment. Inactivation levels were lower for depth-plated cells: indeed,... |
Tipo: Text |
Palavras-chave: Efficiency; Inactivation; Bacteria; Treatment; Pulsed light. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3041.pdf |
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Hugoni, Mylene; Escalas, Arthur; Bernard, Cecile; Nicolas, Sebastien; Jezequel, Didier; Vazzoler, Fanny; Sarazin, Gerard; Leboulanger, Christophe; Bouvy, Marc; Got, Patrice; Ader, Magali; Troussellier, Marc; Agogue, Helene. |
Thalassohaline ecosystems are hypersaline environments originating from seawater in which sodium chloride is the most abundant salt and the pH is alkaline. Studies focusing on microbial diversity in thalassohaline lakes are still scarce compared with those on athalassohaline lakes such as soda lakes that have no marine origin. In this work, we investigated multiple facets of bacterial, archaeal and eukaryotic diversity in the thalassohaline Lake Dziani Dzaha using a metabarcoding approach. We showed that bacterial and archaeal diversity were mainly affected by contrasting physicochemical conditions retrieved at different depths. While photosynthetic microorganisms were dominant in surface layers, chemotrophic phyla (Firmicutes or Bacteroidetes) and... |
Tipo: Text |
Palavras-chave: Archaea; Bacteria; Eukaryotes; Extreme environment; Metabarcoding; Thalassohaline lake. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00464/57564/59738.pdf |
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Lakshmanaperumalsamy, P; Chandramohan, D; Natarajan, R. |
A seasonal study on the occurrence and distribution of total aerobic microbial population (TMP), total aerobic heterotrophic bacteria (THB), actinomycetes and fungi in the sediments of Vellar Estuary, South India (11 degree 29'N 79 degree 46'E) was carried out during Jan. to Dec. 1975. Sediment samples were collected at monthly intervals, from 4 stations and analysed microbiologically. In general, bacterial population was found to be dominant followed by actinomycetes and fungi. The max peak for TMP, THB and fungi were recorded in Nov. in all stations. Monsoon season supported TMP, THB and fungi to a high level and it was summer for actinomycetes. Statistical analysis (Kendall's tau) showed a significantly positive correlation among TMP, THB, actinomycetes... |
Tipo: Text |
Palavras-chave: Actinomycetes; Population number; Statistical analysis; Seasonal variations; Fungi; Bacteria; Sediment analysis; Microbiological analysis. |
Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-943.pdf |
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Montanie, Helene; Ory, Pascaline; Orvain, Francis; Delmas, Daniel; Dupuy, Christine; Hartmann, Hans J.. |
In shallow macrotidal ecosystems with large intertidal mudflats, the sediment-water coupling plays a crucial role in structuring the pelagic microbial food web functioning, since inorganic and organic matter and microbial components (viruses and microbes) of the microphytobenthic biofilm can be suspended toward the water column. Two experimental bioassays were conducted in March and July 2008 to investigate the importance of biofilm input for the pelagic Microbial and Viral Loops. Pelagic inocula (< 0.6 μ- and < 10 μ filtrates) were diluted either with < 30 kDa-ultrafiltered seawater or with this ultrafiltrate enriched with the respective size-fractionated benthic biofilm or with < 30 kDa-benthic compounds (BC). The kinetics of heterotrophic... |
Tipo: Text |
Palavras-chave: Mudflats; Virus; Bacteria; HNF; Coastal water. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00166/27691/25883.pdf |
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Rzeznik-orignac, Jadwiga; Puisay, Antoine; Derelle, Evelyne; Peru, Erwan; Le Bris, Nadine; Galand, Pierre E.. |
In submarine canyon sediments, bacteria and nematodes dominate the benthic biomass and play a key role in nutrient cycling and energy transfer. The diversity of these communities remains, however, poorly studied. This work aims at describing the composition of bacteria and nematode communities in the Lacaze-Duthiers submarine canyon in the north-western Mediterranean Sea. We targeted three sediment depths for two consecutive years and investigated the communities using nuclear markers (18S rRNA and 16S rRNA genes). High throughput sequencing combined to maximal information coefficient (MIC) statistical analysis allowed us to identify, for the first time, at the same small scale, the community structures and the co-occurrence of nematodes and bacteria... |
Tipo: Text |
Palavras-chave: Bacteria; Meiofauna; Canyon Lacaze-Duthiers; Metabarcording; Molecular approach; Mediterranean Sea; Nematodes; Marine biodiversity; 18S; 16S. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00454/56586/76447.pdf |
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FERNANDES Jr.,A.; SUGIZAKI,M.F.; FOGO,M.L.; FUNARI,S.R.C.; LOPES,C.A.M.. |
The in vitro activity of propolis against 118 Staphylococcus aureus, 108 Escherichia coli, 60 Salmonella typhimurium, 50 Candida albicans, 23 Candida parapsilosis, 19 Candida tropicalis and 14 Candida guilliermondii isolated from human infections was studied by the agar dilution method. Among the bacteria, the Gram-negative were the least susceptible organisms showing minimal inhibitory concentration (MIC) for 90% of the strains tested ranging from 22.5 mg/ml - 10,2% V/V to 23.1 mg/ml - 10.5% V/V. The MIC's for Candida ranged from 0.80 mg/ml to > 11 mg/ml (0.40% V/V to > 5.0% V/V), the strains of C. parapsilosis being the least susceptible. The relative order of susceptibility among all isolates, was: S.aureus > C. tropicalis >... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Propolis; Antimicrobial activity; Bacteria; Yeast pathogens; Candida sp. |
Ano: 1995 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0104-79301995000200003 |
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Registros recuperados: 341 | |
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