Consulta: creatorFacets:"Saint-jean, Bruno"
Registros recuperados: 16
Data/hora: 06/06/2024 18:37:38

Effects of blue light on the biochemical composition and photosynthetic activity of Isochrysis sp. (T-iso)
Provedor de dados: 5
Autores: Marchetti, Julie; Bougaran, Gael; Jauffrais, Thierry; Lefebvre, Sebastien; Rouxel, Catherine; Saint-jean, Bruno; Lukomska, Ewa; Robert, Rene; Cadoret, Jean-paul.
In aquaculture, particularly in bivalve hatcheries, the biochemical composition of algal diets has a strong influence on larval and post-larval development. Biochemical composition is known to be related to culture conditions, among which light represents a major source of variation. The effects of blue light on biochemical composition and photosynthetic rate of Isochrysis sp. (T-iso) CCAP 927/14 were assessed in chemostat at a single irradiance (300 μmol photons m−2 s−1) and compared with white light. Two different dilution (renewal) rates were also tested: 0.7 and 0.2 d−1. Relative carbohydrate content was lower under blue light than under white light at both dilution rates, whereas chlorophyll a and photosynthesis activity were higher. In contrast,...
Tipo: Text
Palavras-chave: Isochrysis; Blue light; Photosynthesis; Proximate composition; Chemostat.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00085/19599/17237.pdf

Use comparative proteomics on a selected microalgae provides candidates for biofuel production.
Provedor de dados: 5
Autores: Garnier, Matthieu; Carrier, Gregory; Rogniaux, Helene; Nicolau, Elodie; Bougaran, Gael; Saint-jean, Bruno; Cadoret, Jean-paul.
Microalgae are photosynthetic microorganisms that have an extraordinary diversity which biotechnological potential is just beginning to be explored. Microalgae in biotechnology are presently the focus of an unprecedented surge in interest and investment worldwide. Understanding microalgal lipid accumulation under nitrogen starvation is of major interest for feedstocks, food and biofuel production. Although studies have been performed in model species, to this day it is critical to understand through particular mechanisms of biotechnological species. Tisochrysis lutea is traditionally used for aquaculture feed and presents advantages for lipid production. The wild type strain and a lipid over-accumulating selected mutant were used to perform the first...
Tipo: Text
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00176/28735/27203.pdf

A transposable element annotation pipeline and expression analysis reveal potentially active elements in the microalga Tisochrysis lutea
Provedor de dados: 5
Autores: Berthelier, Jeremy; Casse, Nathalie; Daccord, Nicolas; Jamilloux, Veronique; Saint-jean, Bruno; Carrier, Gregory.
Background Transposable elements (TEs) are mobile DNA sequences known as drivers of genome evolution. Their impacts have been widely studied in animals, plants and insects, but little is known about them in microalgae. In a previous study, we compared the genetic polymorphisms between strains of the haptophyte microalga Tisochrysis lutea and suggested the involvement of active autonomous TEs in their genome evolution. Results To identify potentially autonomous TEs, we designed a pipeline named PiRATE (Pipeline to Retrieve and Annotate Transposable Elements, download: https://doi.org/10.17882/51795), and conducted an accurate TE annotation on a new genome assembly of T. lutea. PiRATE is composed of detection, classification and annotation steps. Its...
Tipo: Text
Palavras-chave: Transposable elements; Genome assembly; Pipeline; Tool; Annotation; Algae; Haptophyte; Tisochrysis lutea.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00441/55250/56732.pdf

Effects of nitrogen limitation on Dunaliella sp.–Alteromonas sp. interactions: from mutualistic to competitive relationships.
Provedor de dados: 5
Autores: Le Chevanton, Myriam; Garnier, Matthieu; Lukomska, Ewa; Schreiber, Nathalie; Cadoret, Jean-paul; Saint-jean, Bruno; Bougaran, Gael.
Interactions between photosynthetic and non-photosynthetic microorganisms play an essential role in natural aquatic environments and the contribution of bacteria and microalgae to the nitrogen cycle can lead to both competitive and mutualistic relationships. Nitrogen is considered to be, with phosphorus and iron, one of the main limiting nutrients for primary production in the oceans and its availability experiences large temporal and geographical variations. For these reasons, it is important to understand how competitive and mutualistic interactions between photosynthetic and heterotrophic microorganisms are impacted by nitrogen limitation. In a previous study performed in batch cultures, the addition of a selected bacterial strain of Alteromonas sp....
Tipo: Text
Palavras-chave: Interactions; Nitrogen limitation; Microalgae; Bacteria; Chemostat; Dissolved organic matter (DOM); Dunaliella.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00344/45529/45087.pdf

Comparative proteomics reveals proteins impacted by nitrogen deprivation in wild-type and high lipid-accumulating mutant strains of Tisochrysis lutea
Provedor de dados: 5
Autores: Garnier, Matthieu; Carrier, Gregory; Rogniaux, Helene; Nicolau, Elodie; Bougaran, Gael; Saint-jean, Bruno; Cadoret, Jean-paul.
Understanding microalgal lipid accumulation under nitrogen starvation is of major interest for biomass feedstock, food and biofuel production. Using a domesticated oleaginous algae Tisochrysis lutea, we performed the first comparative proteomic analysis on the wild type strain and a selected lipid over-accumulating mutant. 2-DE analysis was made on these strains cultured in two metabolic conditions, with and without nitrogen deprivation, which revealed significant differences in proteomes according to both strain and nitrogen availability. Mass spectrometry allowed us to identify 37 proteins that were differentially expressed between the two strains, and 17 proteins regulated by nitrogen starvation concomitantly with lipid accumulation. The proteins...
Tipo: Text
Palavras-chave: Microalgae; Biotechnology; Lipid; Nitrogen; Proteomic; Selection.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00179/29012/27470.pdf

Microalgues: de petits végétaux aux grandes promesses !
Provedor de dados: 5
Autores: Bougaran, Gael; Saint-jean, Bruno.
Pour nos sociétés modernes, en quête de nouveaux procédés et de molécules actives innovantes, les microalgues représentent un formidable potentiel. Leurs nombreuses espèces et leur biodiversité constituent un réservoir de métabolites et de propriétés biochimiques quasi-inexploré, pour le développement de nouvelles applications biotechnologiques.
Tipo: Text
Ano: 2014
URL: https://archimer.ifremer.fr/doc/00252/36321/34885.pdf

Comparative Transcriptome of Wild Type and Selected Strains of the Microalgae Tisochrysis lutea Provides Insights into the Genetic Basis, Lipid Metabolism and the Life Cycle
Provedor de dados: 5
Autores: Carrier, Gregory; Garnier, Matthieu; Le Cunff, Loic; Bougaran, Gael; Probert, Ian; De Vargas, Colomban; Corre, E; Cadoret, Jean-paul; Saint-jean, Bruno.
The applied exploitation of microalgae cultures has to date almost exclusively involved the use of wild type strains, deposited over decades in dedicated culture collections. Concomitantly, the concept of improving algae with selection programs for particular specific purposes is slowly emerging. Studying since a decade an economically and ecologically important haptophyte Tisochrysis lutea (Tiso), we took advantage of the availability of wild type (Tiso-Wt) and selected (Tiso-S2M2) strains to conduct a molecular variations study. This endeavour presented substantial challenges: the genome assembly was not yet available, the life cycle unknown and genetic diversity of Tiso-Wt poorly documented. This study brings the first molecular data in order to set up...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00175/28662/27089.pdf

Microalgae, Functional Genomics and Biotechnology
Provedor de dados: 5
Autores: Cadoret, Jean-paul; Garnier, Matthieu; Saint-jean, Bruno.
Microalgae have been studied for decades, but a new wave of research has recently begun as part of the search for renewable and sustainable energy sources. For economic optimization, microalgal biomass is being considered as a whole (main products and co-products) in an overall 'biorefinery' concept Applications of microalgae cover a broad spectrum, including the food and (livestock) feed industries, bio-energy, cosmetics, healthcare and environmental restoration or protection. In the field of biotechnology, the access to genomic data is playing a growing role. As the cost of sequencing strategies has fallen, studies of gene function at the transcript, protein and biosynthesis pathway levels have multiplied. Notably, sequencing and mass spectrometry...
Tipo: Text
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00125/23602/21477.pdf

Betaine lipid and neutral lipid production under nitrogen or phosphorus limitation in the marine microalga Tisochrysis lutea (Haptophyta)
Provedor de dados: 5
Autores: Huang, Bing; Marchand, Justine; Thiriet-rupert, Stanislas; Carrier, Gregory; Saint-jean, Bruno; Lukomska, Ewa; Moreau, Brigitte; Morant-manceau, Annick; Bougaran, Gael; Mimouni, Virginie.
Nitrogen (N) and phosphorus (P) limitations induce neutral lipid accumulation and membrane lipid remodeling in the domesticated oleaginous microalga Tisochrysis lutea. This study compared growth, photosynthetic activity, biochemical and transcriptional responses of T. lutea throughout batch cultures under N or P limitation compared with non-limiting nutrient condition (NP). The results show that, under N limitation, the breakdown and re-use of cellular N-containing compounds contributed to carbohydrates and further triacylglycerol (TAG) accumulation, where the accumulation of docosahexaenoic acid (DHA) in neutral lipids might mainly be derived from the recycling of membrane polar lipids. Conversely, P limitation did not hinder the photosynthetic capacity;...
Tipo: Text
Palavras-chave: Tisochrysis lutea; Phosphorus; Nitrogen; Lipid remodeling; Betaine lipid; Polyunsaturated fatty acid.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00492/60409/64776.pdf

The use of fluorescent Nile red and BODIPY for lipid measurement in microalgae
Provedor de dados: 5
Autores: Rumin, Judith; Bonnefond, Hubert; Saint-jean, Bruno; Rouxel, Catherine; Sciandra, Antoine; Bernard, Olivier; Cadoret, Jean-paul; Bougaran, Gael.
Microalgae are currently emerging as one of the most promising alternative sources for the next generation of food, feed, cosmetics and renewable energy in the form of biofuel. Microalgae constitute a diverse group of microorganisms with advantages like fast and efficient growth. In addition, they do not compete for arable land and offer very high lipid yield potential. Major challenges for the development of this resource are to select lipid-rich strains using high-throughput staining for neutral lipid content in microalgae species. For this purpose, the fluorescent dyes most commonly used to quantify lipids are Nile red and BODIPY 505/515. Their fluorescent staining for lipids offers a rapid and inexpensive analysis tool to measure neutral lipid content,...
Tipo: Text
Palavras-chave: Nile red; BODIPY 505/515; Microalgae; Neutral lipid; Fluorescence; Biodiesel.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00257/36823/35451.pdf

Use of a lipid rich strain reveals mechanisms of nitrogen limitation and carbon partitioning in the haptophyte Tisochrysis lutea
Provedor de dados: 5
Autores: Garnier, Matthieu; Bougaran, Gael; Pavlovic, Marija; Berard, Jean-baptiste; Carrier, Gregory; Charrier, Aurelie; Le Grand, Fabienne; Lukomska, Ewa; Rouxel, Catherine; Schreiber, Nathalie; Cadoret, Jean-paul; Rogniaux, Helene; Saint-jean, Bruno.
Haptophytes are a diverse monophyletic group with a worldwide distribution, known to be significantly involved in global climate regulation in their role as a carbon sink. Because nitrogen is a major limiting macronutrient for phytoplankton in oceans and for cultures of microalgae, understanding the involvement of nitrogen availability in haptophyte carbon partitioning is of global and biotechnological importance. Here, we made an ecophysiological study coupled with comprehensive large scale proteomic analysis to examine differences of behavior in reaction to nitrogen availability changes between a wild type strain of Tisochrysis lutea (WTc1) and a mutant strain (2Xc1) known to accumulate more storage lipids. Strains were grown in chemostats and studied...
Tipo: Text
Palavras-chave: Algae; Isochrysis; Lipids; Nitrogen; Reverse genomic: proteomic.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00356/46702/46904.pdf

Transcription factors in microalgae: genome-wide prediction and comparative analysis
Provedor de dados: 5
Autores: Thiriet-rupert, Stanislas; Carrier, Gregory; Chenais, Benoit; Trottier, Camille; Bougaran, Gael; Cadoret, Jean-paul; Schoefs, Benoit; Saint-jean, Bruno.
Background: Studying transcription factors, which are some of the key players in gene expression, is of outstanding interest for the investigation of the evolutionary history of organisms through lineage-specific features. In this study we performed the first genome-wide TF identification and comparison between haptophytes and other algal lineages. Results: For TF identification and classification, we created a comprehensive pipeline using a combination of BLAST, HMMER and InterProScan software. The accuracy evaluation of the pipeline shows its applicability for every alga, plant and cyanobacterium, with very good PPV and sensitivity. This pipeline allowed us to identify and classified the transcription factor complement of the three haptophytes...
Tipo: Text
Palavras-chave: Algae; Endosymbiotic gene transfer; Haptophytes; Prediction pipeline; Stramenopiles; Tisochrysis lutea; Transcription factors.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00333/44403/44072.pdf

N-Glycans of Phaeodactylum tricornutum Diatom and Functional Characterization of Its N-Acetylglucosaminyltransferase I Enzyme
Provedor de dados: 5
Autores: Baiet, Berengere; Burel, Carole; Saint-jean, Bruno; Louvet, Romain; Menu-bouaouiche, Laurence; Kiefer-meyer, Marie-christine; Mathieu-rivet, Elodie; Lefebvre, Thomas; Castel, Helene; Carlier, Aude; Cadoret, Jean-paul; Lerouge, Patrice; Bardor, Muriel.
N-Glycosylation, a major co- and post-translational event in the synthesis of proteins in eukaryotes, is unknown in aquatic photosynthetic microalgae. In this paper, we describe the N-glycosylation pathway in the diatom Phaeodactylum tricornutum. Bio-informatic analysis of its genome revealed the presence of a complete set of sequences potentially encoding for proteins involved in the synthesis of the lipid-linked Glc(3)Man(9)GlcNAc(2)-PP-dolichol N-glycan, some subunits of the oligosaccharyltransferase complex, as well as endoplasmic reticulum glucosidases and chaperones required for protein quality control and, finally, the alpha-mannosidase I involved in the trimming of the N-glycan precursor into Man-5 N-glycan. Moreover, one...
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00031/14184/11951.pdf

Proteomic Analysis of the Chlorophyta Dunaliella New Strain AL-1 Revealed Global Changes of Metabolism during High Carotenoid Production
Provedor de dados: 5
Autores: Ben Amor, Faten; Elleuch, Fatma; Ben Hlima, Hajer; Garnier, Matthieu; Saint-jean, Bruno; Barkallah, Mohamed; Pichon, Chantal; Abdelkafi, Slim; Fendri, Imen.
The green microalgae Dunaliella genus is known for the production of high added value molecules. In this study, strain AL-1 was isolated from the Sebkha of Sidi El Hani (Sousse, Tunisia). This isolate was identified both morphologically and genetically via 18S rRNA gene sequence as a member of the genus Dunaliella. Strain AL-1 was found to be closely related to Dunaliella salina, Dunaliella quartolecta and Dunaliella polymorpha with more than 97% similarity. Response surface methodology was used to maximize carotenoid production by strain AL-1 by optimizing its growth conditions. The highest carotenoid content was obtained at salinity: 51, light intensity: 189.89 μmol photons·m−2·s−1, and nitrogen: 60 mg·L−1. Proteomic profiling, using two-dimensional gel...
Tipo: Text
Palavras-chave: Proteome; Dunaliella; 18S rRNA gene; Carotenoids; Bidimensional gel electrophoresis; Mass spectrometry.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00402/51398/51973.pdf

High-affinity nitrate/nitrite transporter genes (Nrt2) in Tisochrysis lutea: identification and expression analyses reveal some interesting specificities of Haptophyta microalgae
Provedor de dados: 5
Autores: Charrier, Aurelie Georgette; Berard, Jean-baptiste; Bougaran, Gael; Carrier, Gregory; Lukomska, Ewa; Schreiber, Nathalie; Fournier, Flora; Charrier, Aurelie; Rouxel, Catherine; Garnier, Matthieu; Cadoret, Jean-paul; Saint-jean, Bruno.
Microalgae have a diversity of industrial applications such as feed, food ingredients, depuration processes and energy. However, microalgal production costs could be substantially improved by controlling nutrient intake. Accordingly, a better understanding of microalgal nitrogen metabolism is essential. Using in silico analysis from transcriptomic data concerning the microalgae Tisochrysis lutea, four genes encoding putative high-affinity nitrate/nitrite transporters (TlNrt2) were identified. Unlike most of the land plants and microalgae, cloning of genomic sequences and their alignment with complementary DNA (cDNA) sequences did not reveal the presence of introns in all TlNrt2 genes. The deduced TlNRT2 protein sequences showed similarities to NRT2...
Tipo: Text
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00253/36467/35044.pdf

Identification of transcription factors involved in the phenotype of a domesticated oleaginous microalgae strain of Tisochrysis lutea
Provedor de dados: 5
Autores: Thiriet-rupert, Stanislas; Carrier, Gregory; Trottier, Camille; Eveillard, D.; Schoefs, B.; Bougaran, Gael; Cadoret, Jean-paul; Chenais, B.; Saint-jean, Bruno.
Microalgae are an outstanding source of high value products with applications in food, feed or biofuel production. Among these promising organisms, the haptophyte Tisochrysis lutea is commonly used as a feed for shellfish and shrimps in aquaculture. Its capacity to produce high amounts of docosahexanoic acid and storage lipids is also of economic interest for nutrition and energy production. Consequently, understanding its lipid accumulation under nitrogen deprivation is of major interest. Here, we aimed to identify Transcription Factors (TFs) involved in the establishment of the mutant phenotype of the 2Xc1 strain of T. lutea, which accumulates double the quantity of storage lipids under nitrogen deprivation than the wild type strain (WTc1). Strains were...
Tipo: Text
Palavras-chave: Algae; Carbohydrates; Gene co-expression network; Lipids; Transcription factor; Tisochrysis lutea.
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00418/52973/53901.pdf