Consulta: creatorFacets:"Masseret, Estelle"
Registros recuperados: 21
Data/hora: 08/06/2024 17:19:46

Unsuspected intraspecific variability in the toxin production, growth and morphology of the dinoflagellate Alexandrium pacificum R.W. Litaker (Group IV) blooming in a South Western Mediterranean marine ecosystem, Annaba Bay (Algeria)
Provedor de dados: 5
Autores: Hadjadji, Imen; Laabir, Mohamed; Frihi, Hocine; Collos, Yves; Shao, Zhao Jun; Berrebi, Patrick; Abadie, Eric; Amzil, Zouher; Chomérat, Nicolas; Rolland, Jean-luc; Rieuvilleneuve, Fabien; Masseret, Estelle.
Physiological plasticity gives HABs species the ability to respond to variations in the surrounding environment. The aim of this study was to examine morphological and physiological variability in Alexandrium pacificum R.W. Litaker (Group IV) (former Alexandrium catenella) blooming in Annaba bay, Algeria. Monoclonal cultures of up to 30 strains of this neurotoxic dinoflagellate were established by the germination of single resting cysts from the surface sediment of this southern Mediterranean marine ecosystem. Ribotyping confirmed formally for the first time that A. pacificum is developing in Eastern Algerian waters. Toxin analyses of A. pacificum strains revealed substantial intraspecific variability in both the profile and toxin amount. However, the...
Tipo: Text
Palavras-chave: Alexandrium pacificum; Mediterranean; Toxin profile; Growth; Intraspecific variability.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00624/73620/73598.pdf

A Feedback Mechanism to Control Apoptosis Occurs in the Digestive Gland of the Oyster Crassostrea gigas Exposed to the Paralytic Shellfish Toxins Producer Alexandrium catenella
Provedor de dados: 5
Autores: Rolland, Jean-luc; Medhioub, Walid; Vergnes, Agnes; Abi-khalil, Celina; Savar, Veronique; Abadie, Eric; Masseret, Estelle; Amzil, Zouher; Laabir, Mohamed.
To better understand the effect of Paralytic Shellfish Toxins (PSTs) accumulation in the digestive gland of the Pacific oyster, Crassostrea gigas, we experimentally exposed individual oysters for 48 h to a PSTs producer, the dinoflagellate Alexandrium catenella. In comparison to the effect of the non-toxic Alexandrium tamarense, on the eight apoptotic related genes tested, Bax and BI.1 were significantly upregulated in oysters exposed 48 h to A. catenella. Among the five detoxification related genes tested, the expression of cytochrome P450 (CYP1A) was shown to be correlated with toxin concentration in the digestive gland of oysters exposed to the toxic dinoflagellate. Beside this, we observed a significant increase in ROS production, a decrease in...
Tipo: Text
Palavras-chave: Shellfish; Toxin; Biomarker; Expression; Phytoplankton.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00225/33606/32003.pdf

What are the main environmental factors driving the development of the neurotoxic dinoflagellate Vulcanodinium rugosum in a Mediterranean ecosystem (Ingril lagoon, France)?
Provedor de dados: 5
Autores: Abadie, Eric; Chiantella, Claude; Crottier, Anais; Rhodes, Lesley; Masseret, Estelle; Berteaux, Tom; Laabir, Mohamed.
Vulcanodinium rugosum, a dinoflagellate developing in Ingril Lagoon (Mediterranean, France) is responsible for shellfish intoxications due to the neurotoxin pinnatoxin G. A one year survey (March 2012–April 2013) was conducted in this oligotrophic shallow lagoon and key environmental parameters were recorded (temperature, salinity and nutrients). The spatio-temporal distribution of V. rugosum in water column and on macrophytes was also determined. Planktonic cells of V. rugosum were observed at all sampling stations, but in relatively low concentrations (maximum of 1000 cell/L). The highest abundances were observed from June to September 2012. There was a positive correlation between cell densities and both temperature and salinity. Non-motile cells were...
Tipo: Text
Palavras-chave: Vulcanodinium rugosum; Neurotoxins; Ingril lagoon; Environmental factors; Development dynamic.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00437/54862/56478.pdf

Influence of Environmental Factors on the Paralytic Shellfish Toxin Content and Profile of Alexandrium catenella (Dinophyceae) Isolated from the Mediterranean Sea
Provedor de dados: 5
Autores: Laabir, Mohamed; Collos, Yves; Masseret, Estelle; Grzebyk, Daniel; Abadie, Eric; Savar, Veronique; Sibat, Manoella; Amzil, Zouher.
Laboratory experiments were designed to study the toxin content and profile of the Alexandrium catenella strain ACT03 (isolated from Thau Lagoon, French Mediterranean) in response to abiotic environmental factors under nutrient-replete conditions. This dinoflagellate can produce various paralytic shellfish toxins with concentrations ranging from 2.9 to 50.3 fmol/cell. The toxin profile was characterized by carbamate toxins (GTX3, GTX4 and GTX5) and N-sulfocarbamoyl toxins (C1, C2, C3 and C4). C2 dominated at 12-18 degrees C, but only for salinities ranging from 10 to 25 psu, whereas GTX5 became dominant at temperatures ranging from 21 to 30 degrees C at almost all salinities. There was no significant variation in the cellular toxin amount from 18 degrees C...
Tipo: Text
Palavras-chave: Alexandrium catenella; PSP toxins; Temperature; Salinity; Light.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00148/25969/24056.pdf

Dietary BMAA Exposure in an Amyotrophic Lateral Sclerosis Cluster from Southern France
Provedor de dados: 5
Autores: Masseret, Estelle; Banack, Sandra; Boumediene, Farid; Abadie, Eric; Brient, Luc; Pernet, Fabrice; Juntas-morales, Raoul; Pageot, Nicolas; Metcalf, James; Cox, Paul; Camu, William.
Background  Dietary exposure to the cyanotoxin BMAA is suspected to be the cause of amyotrophic lateral sclerosis in the Western Pacific Islands. In Europe and North America, this toxin has been identified in the marine environment of amyotrophic lateral sclerosis clusters but, to date, only few dietary exposures have been described.  Objectives  We aimed at identifying cluster(s) of amyotrophic lateral sclerosis in the Hérault district, a coastal district from Southern France, and to search, in the identified area(s), for the existence of a potential dietary source of BMAA.  Methods  A spatio-temporal cluster analysis was performed in the district, considering all incident amyotrophic lateral sclerosis cases identified from 1994 to 2009 by our expert...
Tipo: Text
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00168/27941/26234.pdf

Relationships between genetic diversity and niche-partitioning of Synechococcus populations in Mediterranean coastal lagoons, systems of transition between freshwater and marine ecosystems
Provedor de dados: 5
Autores: Masseret, Estelle; Bierne, Nicolas; Chevret, Pascale; Roumagnac, Marie; Bec, Béatrice; Laugier, Thierry; Collos, Yves; Vaquer, Andre.
Coastal lagoons are morphologically and ecologically complex ecosystems, subject to constantly changing environmental conditions generally of much greater magnitude than it is recorded in the open sea. Due to their transitional nature, they usually display a number of specific features (ie. high nutrient concentrations, light spectral quality, salinity range) which are potentially influencing strategies of adaptation of photosynthetic microorganisms. The unicellular cyanobacteria Synechococcus is a major component of marine and freshwater picophytoplankton. Its genetic diversity is well documented for these ecosystems, but knowledge about biodiversity and distribution of this genus in transitional waters remains scarce. The phylogenetic analysis of a...
Tipo: Text
Ano: 2007
URL: http://archimer.ifremer.fr/doc/00011/12198/8960.pdf

Algicidal effects of Zostera marina L. and Zostera noltii Hornem. extracts on the neuro-toxic bloom-forming dinoflagellate Alexandrium catenella
Provedor de dados: 5
Autores: Laabir, Mohamed; Grignon-dubois, Micheline; Masseret, Estelle; Rezzonico, Bernadette; Soteras, Giselle; Rouquette, Manuel; Rieuvilleneuve, Fabien; Cecchi, Philippe.
The inhibitory effects of crude extracts of Zostera marina L and Zostera noltii Hornemann on the growth of the toxic red tide dinoflagellate Alexandrium catenella were investigated through bio-assays. Methanolic and aqueous extracts were prepared from fresh and detrital leaves of Z. marina and Z. noltii collected in the Thau lagoon and Arcachon bay (France). All the extracts exhibited significant inhibition of A. catenella growth, whatever the species and without the need of continuous addition of extracts. The effective concentrations (EC50) varied in the range 0.036-0.199 g L-1 for Z. noltii and 0.036-0.239 g L-1 for Z. marina. Methanolic extracts prepared from fresh plant tissues were the most potent, with EC50 of 0.036-0.039 and 0.036-0.045 g L-1, for...
Tipo: Text
Palavras-chave: Growth inhibition; Allelopathy; Alexandrium catenella; Zostera marina; Zostera noltii; Phenolics.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00170/28095/26720.pdf

Searching for a link between the L-BMAA neurotoxin and amyotrophic lateral sclerosis: a study protocol of the French BMAALS programme
Provedor de dados: 5
Autores: Delzor, Aurelie; Couratier, Philippe; Boumediene, Farid; Nicol, Marie; Druet-cabanac, Michel; Paraf, Francois; Mejean, Annick; Ploux, Olivier; Leleu, Jean-philippe; Brient, Luc; Lengronne, Marion; Pichon, Valerie; Combes, Audrey; El Abdellaoui, Saida; Bonneterre, Vincent; Lagrange, Emmeline; Besson, Gerard; Bicout, Dominique J.; Boutonnat, Jean; Camu, William; Pageot, Nicolas; Juntas-morales, Raul; Rigau, Valerie; Masseret, Estelle; Abadie, Eric; Preux, Pierre-marie; Marin, Benoit.
Introduction: Amyotrophic lateral sclerosis (ALS) is the most common motor neurone disease. It occurs in two forms: (1) familial cases, for which several genes have been identified and (2) sporadic cases, for which various hypotheses have been formulated. Notably, the beta-N-methylamino-L-alanine (L-BMAA) toxin has been postulated to be involved in the occurrence of sporadic ALS. The objective of the French BMAALS programme is to study the putative link between L-BMAA and ALS. Methods and analysis: The programme covers the period from 1 January 2003 to 31 December 2011. Using multiple sources of ascertainment, all the incident ALS cases diagnosed during this period in the area under study (10 counties spread over three French regions) were collected....
Tipo: Text
Ano: 2014
URL: https://archimer.ifremer.fr/doc/00443/55431/56952.pdf

Viability, growth and toxicity of Alexandrium catenella and Alexandrium minutum (Dinophyceae) following ingestion and gut passage in the oyster Crassostrea gigas
Provedor de dados: 5
Autores: Laabir, Mohamed; Amzil, Zouher; Lassus, Patrick; Masseret, Estelle; Tapilatu, Yosmina; De Vargas, Romain; Grzebyk, Daniel.
Adult oysters Crassostrea gigas were experimentally fed with Alexandrium catenella and Alexandrium minutum which are responsible for recurrent toxic blooms in French coastal waters. C. gigas produced faeces and pseudofaeces containing intact and viable temporary pellicular cysts of these two Paralytic toxin producing species. When incubated in favourable conditions, these pellicular cysts were able to germinate at high rates (between 74 and 94%) and the resulting vegetative cells divided with growth rates close to the non-ingested cells (control). The toxin profile of the vegetative cells originated from the germinated temporary cysts was analyzed by liquid chromatography/ fluorescence detection. Total toxin content of newly germinated cells was lower than...
Tipo: Text
Palavras-chave: Paralytic shellfish poisoning; Oysters; Cysts; Alexandrium minutum; Alexandrium catenella.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2622.pdf

Effets de l'algue toxique Alexandrium catenella sur le système de défense de l'huître creuse Crassostrea gigas
Provedor de dados: 5
Autores: Medhioub, Walid; Duchiron, Marie; Masseret, Estelle; Savar, Veronique; Amzil, Zouher; Laabir, Mohamed; Rolland, Jean-luc.
Tipo: Text
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00172/28332/26618.pdf

Exposure to the Neurotoxic Dinoflagellate, Alexandrium catenella, Induces Apoptosis of the Hemocytes of the Oyster, Crassostrea gigas
Provedor de dados: 5
Autores: Medhioub, Walid; Ramondenc, Simon; Vanhove, Audrey; Vergnes, Agnes; Masseret, Estelle; Savar, Veronique; Amzil, Zouher; Laabir, Mohamed; Rolland, Jean-luc.
This study assessed the apoptotic process occurring in the hemocytes of the Pacific oyster, Crassostrea gigas, exposed to Alexandrium catenella, a paralytic shellfish toxins (PSTs) producer. Oysters were experimentally exposed during 48 h to the toxic algae. PSTs accumulation, the expression of 12 key apoptotic-related genes, as well as the variation of the number of hemocytes in apoptosis was measured at time intervals during the experiment. Results show a significant increase of the number of hemocytes in apoptosis after 29 h of exposure. Two pro-apoptotic genes (Bax and Bax-like) implicated in the mitochondrial pathway were significantly upregulated at 21 h followed by the overexpression of two caspase executor genes (caspase-3 and caspase-7) at 29 h,...
Tipo: Text
Palavras-chave: Shellfish; Toxins; Apoptosis; Gene expression.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00176/28744/27213.pdf

β-N-methylamino-l-alanine (BMAA) and isomers: Distribution in different food web compartments of Thau lagoon, French Mediterranean Sea
Provedor de dados: 5
Autores: Reveillon, Damien; Abadie, Eric; Sechet, Veronique; Masseret, Estelle; Hess, Philipp; Amzil, Zouher.
The neurotoxin BMAA (β-N-methylamino-l-alanine) and its isomer DAB (2,4-diaminobutyric acid) have been detected in seafood worldwide, including in Thau lagoon (French Mediterranean Sea). A cluster of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease associated with BMAA, has also been observed in this region. Mussels, periphyton (i.e. biofilms attached to mussels) and plankton were sampled between July 2013 and October 2014, and analyzed using HILIC-MS/MS. BMAA, DAB and AEG (N-(2-aminoethyl)glycine) were found in almost all the samples of the lagoon. BMAA and DAB were present at 0.58 and 0.83, 2.6 and 3.3, 4.0 and 7.2 μg g−1 dry weight in plankton collected with nets, periphyton and mussels, respectively. Synechococcus sp., Ostreococcus...
Tipo: Text
Palavras-chave: BMAA; Diatoms; Chaetoceros sp.; Seston; Mytilus galloprovincialis; HILIC-MS/MS.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00275/38607/37192.pdf

Phased oscillations in cell numbers and nitrate in batch cultures of Alexandrium tamarense (Dinophyceae)
Provedor de dados: 5
Autores: Collos, Yves; Hadjadji, Imene; Plisson, Benoit; Cecchi, Philippe; Laabir, Mohamed; Bechemin, Christian; Masseret, Estelle.
Alexandrium tamarense (M. Lebour) Balech strains isolated in spring 2007 from a single bloom in Thau lagoon have been grown in nonaxenic artificial media. For three strains showing large oscillations in biomass (crashes followed by recoveries) on a scale of several days, a significant relationship was observed between changes in cell densities (as in vivo fluorescence) and changes in nitrate concentrations. Increases in cell densities were accompanied by decreases in nitrate, while decreases in cell densities corresponded to increases in nitrate, presumably due to nitrification. Net increases in nitrate could reach up to 15 mu mol N . L(-1) . d(-1) indicating a very active nitrifying archaeal/bacterial population. However, following population crashes,...
Tipo: Text
Palavras-chave: Alexandrium tamarense; Archaea; Bacteria; Decay; Growth; Nitrate; Nitrification; Oscillations.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00049/16046/13585.pdf

Resting Cyst Distribution and Molecular Identification of the Harmful Dinoflagellate Margalefidinium polykrikoides (Gymnodiniales, Dinophyceae) in Lampung Bay, Sumatra, Indonesia
Provedor de dados: 5
Autores: Thoha, Hikmah; Muawanah,; Bayu Intan, Mariana D.; Rachman, Arief; Sianturi, Oksto Ridho; Sidabutar, Tumpak; Iwataki, Mitsunori; Takahashi, Kazuya; Avarre, Jean-christophe; Masseret, Estelle.
Margalefidinium polykrikoides, an unarmored dinoflagellate, was suspected to be the causative agent of the harmful algal blooms – associated with massive fish mortalities – that have occurred continually in Lampung Bay, Indonesia, since the first bloom event in October 2012. In this study, after examination of the morphology of putative M. polykrikoides-like cysts sampled in bottom sediments, cyst bed distribution of this harmful species was explored in the inner bay. Sediment samples showed that resting cysts, including several morphotypes previously reported as M. polykrikoides, were most abundant on the northern coast of Lampung Bay, ranging from 20.6 to 645.6 cysts g-1 dry sediment. Molecular phylogeny inferred from LSU rDNA revealed that the so-called...
Tipo: Text
Palavras-chave: Margalefidinium polykrikoides; Dinoflagellate; Harmful algal blooms; Resting and hyaline cysts; Indonesia.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00489/60086/63423.pdf

Effect of Nitrate, Ammonium and Urea on Growth and Pinnatoxin G Production of Vulcanodinium rugosum
Provedor de dados: 5
Autores: Abadie, Eric; Kaci, Lamia; Berteaux, Tom; Hess, Philipp; Sechet, Veronique; Masseret, Estelle; Rolland, Jean-luc; Laabir, Mohamed.
ulcanodinium rugosum, a recently described dinoflagellate species producing a potent neurotoxin (pinnatoxin G), has been identified in French Mediterranean lagoons and was responsible for recurrent episodes of shellfish toxicity detected by mouse bioassay. Until now, the biology and physiology of V. rugosum have not been fully investigated. We studied the growth characteristics and toxicity of a V. rugosum strain (IFR-VRU-01), isolated in the Ingril lagoon in June 2009 (North-Western French Mediterranean Sea). It was cultivated in Enriched Natural Sea Water (ENSW) with organic (urea) and inorganic (ammonium and nitrate) nitrogen, at a temperature of 25 °C and irradiance of 100 μmol/m2·s−1. Results showed that ammonium was assimilated by cells more rapidly...
Tipo: Text
Palavras-chave: Vulcanodinium rugosum; Pinnatoxin G; Ingril lagoon; Growth; Nitrogen source.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00276/38748/37290.pdf

New insights on the species-specific allelopathic interactions between macrophytes and marine HAB dinoflagellates
Provedor de dados: 5
Autores: Ben Gharbia, Hela; Yahia, Ons Kefi-daly; Cecchi, Philippe; Masseret, Estelle; Amzil, Zouher; Herve, Fabienne; Rovillon, Georges-augustin; Nouri, Habiba; M'Rabet, Charaf; Couet, Douglas; Triki, Habiba Zmerli; Laabir, Mohamed.
Macrophytes are known to release allelochemicals that have the ability to inhibit the proliferation of their competitors. Here, we investigated the effects of the fresh leaves of two magnoliophytes (Zostera noltei and Cymodocea nodosa) and thalli of the macroalgae Ulva rigida on three HAB-forming benthic dinoflagellates (Ostreopsis cf. ovata, Prorocentrum lima, and Coolia monotis). The effects of C. nodosa and U. rigida were also tested against the neurotoxic planktonic dinoflagellate Alexandrium pacificum Litaker sp. nov (former Alexandrium catenella). Co-culture experiments were conducted under controlled laboratory conditions and potential allelopathic effects of the macrophytes on the growth, photosynthesis and toxin production of the targeted...
Tipo: Text
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00411/52200/52917.pdf

Isolation of 12 microsatellite markers following a pyrosequencing procedure and cross-priming in two invasive cryptic species, Alexandrium catenella (group IV) and A. tamarense (group III) (Dinophyceae)
Provedor de dados: 5
Autores: Laporte, Martin; Shao, Zhaojun; Berrebi, Patrick; Laabir, Mohamed; Abadie, Eric; Faivre, Nicolas; Rieuvilleneuve, Fabien; Masseret, Estelle.
Alexandrium catenella (group IV) and Alexandrium tamarense (group III) (Dinophyceae) are two cryptic invasive phytoplankton species belonging to the A. tamarense species complex. Their worldwide spread is favored by the human activities, transportation and climate change. In order to describe their diversity in the Mediterranean Sea and understand their settlements and maintenances in this area, new microsatellite markers were developed based on Thau lagoon (France) samples of A. catenella and A. tamarense strains. In this study twelve new microsatellite markers are proposed. Five of these microsatellite markers show amplifications on A. tamarense and ten on A. catenella. Three of these 12 microsatellite markers allowed amplifications on both cryptic...
Tipo: Text
Palavras-chave: Invasive species; Phytoplankton; Alexandrium; Dinophyceae; Microsatellite markers; Biogeography.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00189/30026/29398.pdf

Toxin and Growth Responses of the Neurotoxic Dinoflagellate Vulcanodinium rugosum to Varying Temperature and Salinity
Provedor de dados: 5
Autores: Abadie, Eric; Muguet, Alexia; Berteaux, Tom; Chomerat, Nicolas; Hess, Philipp; Roque D'Orbcastel, Emmanuelle; Masseret, Estelle; Laabir, Mohamed.
Vulcanodinium rugosum, a recently described species, produces pinnatoxins. The IFR-VRU-01 strain, isolated from a French Mediterranean lagoon in 2010 and identified as the causative dinoflagellate contaminating mussels in the Ingril Lagoon (French Mediterranean) with pinnatoxin-G, was grown in an enriched natural seawater medium. We tested the effect of temperature and salinity on growth, pinnatoxin-G production and chlorophyll a levels of this dinoflagellate. These factors were tested in combinations of five temperatures (15, 20, 25, 30 and 35 °C) and five salinities (20, 25, 30, 35 and 40) at an irradiance of 100 µmol photon m−2 s−1. V. rugosum can grow at temperatures and salinities ranging from 20 °C to 30 °C and 20 to 40, respectively. The optimal...
Tipo: Text
Palavras-chave: Vulcanodinium rugosum; Mediterranean Ingril Lagoon; Toxin production; Growth conditions; Temperature; Salinity.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00333/44429/44095.pdf

Paralytic Toxins Accumulation and Tissue Expression of alpha-Amylase and Lipase Genes in the Pacific Oyster Crassostrea gigas Fed with the Neurotoxic Dinoflagellate Alexandrium catenella
Provedor de dados: 5
Autores: Rolland, Jean-luc; Pelletier, Kevin; Masseret, Estelle; Rieuvilleneuve, Fabien; Savar, Veronique; Santini, Adrien; Amzil, Zouher.
The pacific oyster Crassostrea gigas was experimentally exposed to the neurotoxic Alexandrium catenella and a non-producer of PSTs, Alexandrium tamarense (control algae), at concentrations corresponding to those observed during the blooming period. At fixed time intervals, from 0 to 48 h, we determined the clearance rate, the total filtered cells, the composition of the fecal ribbons, the profile of the PSP toxins and the variation of the expression of two a-amylase and triacylglecerol lipase precursor (TLP) genes through semi-quantitative RT-PCR. The results showed a significant decrease of the clearance rate of C. gigas fed with both Alexandrium species. However, from 29 to 48 h, the clearance rate and cell filtration activity increased only in oysters...
Tipo: Text
Palavras-chave: Crassostrea gigas; Alexandrium catenella; PSP toxins; Digestion; Gene expression.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00130/24170/22172.pdf

Toxicity and Growth Assessments of Three Thermophilic Benthic Dinoflagellates (Ostreopsis cf. ovata, Prorocentrum lima and Coolia monotis) Developing in the Southern Mediterranean Basin
Provedor de dados: 5
Autores: Ben-gharbia, Hela; Yahia, Ons Kefi-daly; Amzil, Zouher; Chomerat, Nicolas; Abadie, Eric; Masseret, Estelle; Sibat, Manoella; Triki, Habiba Zmerli; Nouri, Habiba; Laabir, Mohamed.
armful benthic dinoflagellates, usually developing in tropical areas, are expanding to temperate ecosystems facing water warming. Reports on harmful benthic species are particularly scarce in the Southern Mediterranean Sea. For the first time, three thermophilic benthic dinoflagellates (Ostreopsis cf. ovata, Prorocentrum lima and Coolia monotis) were isolated from Bizerte Bay (Tunisia, Mediterranean) and monoclonal cultures established. The ribotyping confirmed the morphological identification of the three species. Maximum growth rates were 0.59 ± 0.08 d−1 for O. cf. ovata, 0.35 ± 0.01 d−1 for C. monotis and 0.33 ± 0.04 d−1 for P. lima. Toxin analyses revealed the presence of ovatoxin-a and ovatoxin-b in O. cf. ovata cells. Okadaic acid and...
Tipo: Text
Palavras-chave: Ostreopsis cf. ovata; Prorocentrum lima; Coolia monotis; Southern Mediterranean Sea; Growth; Toxicity.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00355/46585/46393.pdf

Intraspecific variability in membrane proteome, cell growth, and morphometry of the invasive marine neurotoxic dinoflagellate Alexandrium pacificum grown in metal-contaminated conditions
Provedor de dados: 5
Autores: Chetouhi, Cherif; Masseret, Estelle; Satta, Cecilia Teodora; Balliau, Thierry; Laabir, Mohamed; Jean, Natacha.
Over the past decades, the occurrence, distribution and intensity of harmful algal blooms involving the dinoflagellate Alexandrium pacificum have increased in marine coastal areas disturbed by anthropogenic inputs. This invasive species produces saxitoxin, which causes the paralytic shellfish poisoning syndrome in humans upon consumption of contaminated seafood. Blooms of A. pacificum have been reported in metal-contaminated coastal ecosystems, suggesting some ability of these microorganisms to adapt to and/or resist in metal stress conditions. This study seeks to characterize the modifications in membrane proteomes (by 2-D electrophoresis coupled to LC-MS/MS), cell growth and morphometry (measured with an inverted microscope), in response to metal stress...
Tipo: Text
Palavras-chave: Alexandrium pacificum; Harmful algal bloom; Proteomics; Membrane pmteome; Trace metals.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00606/71802/70290.pdf