Consulta: creatorFacets:"Massana, Ramon"
Registros recuperados: 9
Data/hora: 09/06/2024 08:37:11

Patterns of Rare and Abundant Marine Microbial Eukaryotes
Provedor de dados: 5
Autores: Logares, Ramiro; Audic, Stephane; Bass, David; Bittner, Lucie; Boutte, Christophe; Christen, Richard; Claverie, Jean-michel; Decelle, Johan; Dolan, John R.; Dunthorn, Micah; Edvardsen, Bente; Gobet, Angelique; Kooistra, Wiebe H. C. F.; Mahe, Frederic; Not, Fabrice; Ogata, Hiroyuki; Pawlowski, Jan; Pernice, Massimo C.; Romac, Sarah; Shalchian-tabrizi, Kamran; Simon, Nathalie; Stoeck, Thorsten; Santini, Sebastien; Siano, Raffaele; Wincker, Patrick; Zingone, Adriana; Richards, Thomas A.; De Vargas, Colomban; Massana, Ramon.
Background  Biological communities are normally composed of a few abundant and many rare species. This pattern is particularly prominent in microbial communities, in which most constituent taxa are usually extremely rare. Although abundant and rare subcommunities may present intrinsic characteristics that could be crucial for understanding community dynamics and ecosystem functioning, microbiologists normally do not differentiate between them. Here, we investigate abundant and rare subcommunities of marine microbial eukaryotes, a crucial group of organisms that remains among the least-explored biodiversity components of the biosphere. We surveyed surface waters of six separate coastal locations in Europe, independently considering the picoplankton,...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00186/29683/28098.pdf

Diversity and distribution of unicellular opisthokonts along the European coast analysed using high-throughput sequencing
Provedor de dados: 5
Autores: Del Campo, Javier; Mallo, Diego; Massana, Ramon; De Vargas, Colomban; Richards, Thomas A.; Ruiz-trillo, Inaki.
The opisthokonts are one of the major super groups of eukaryotes. It comprises two major clades: (i) the Metazoa and their unicellular relatives and (ii) the Fungi and their unicellular relatives. There is, however, little knowledge of the role of opisthokont microbes in many natural environments, especially among non-metazoan and non-fungal opisthokonts. Here, we begin to address this gap by analysing high-throughput 18S rDNA and 18S rRNA sequencing data from different European coastal sites, sampled at different size fractions and depths. In particular, we analyse the diversity and abundance of choanoflagellates, filastereans, ichthyosporeans, nucleariids, corallochytreans and their related lineages. Our results show the great diversity of...
Tipo: Text
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00374/48492/48863.pdf

The Protist Ribosomal Reference database (PR2): a catalog of unicellular eukaryote Small Sub-Unit rRNA sequences with curated taxonomy
Provedor de dados: 5
Autores: Guillou, Laure; Bachar, Dipankar; Audic, S; Bass, David; Berney, Cedric; Bittner, Lucie; Boutte, Christophe; Burgaud, Gaetan; De Vargas, Colomban; Decelle, Johan; Del Campo, Javier; Dolan, John R.; Dunthorn, Micah; Edvardsen, Bente; Holzmann, Maria; Kooistra, Wiebe H. C. F.; Lara, Enrique; Le Bescot, Noan; Logares, Ramiro; Mahe, F; Massana, Ramon; Montresor, Marina; Morard, Raphael; Not, Fabrice; Pawlowski, Jan; Probert, Ian; Sauvadet, Anne-laure; Siano, Raffaele; Stoeck, Thorsten; Vaulot, Daniel; Zimmermann, Pascal; Christen, Richard.
The interrogation of genetic markers in environmental meta-barcoding studies is currently seriously hindered by the lack of taxonomically curated reference data sets for the targeted genes. The Protist Ribosomal Reference database (PR2, http://ssurrna. org/) provides a unique access to eukaryotic small sub-unit (SSU) ribosomal RNA and DNA sequences, with curated taxonomy. The database mainly consists of nuclear-encoded protistan sequences. However, metazoans, land plants, macrosporic fungi and eukaryotic organelles (mitochondrion, plastid and others) are also included because they are useful for the analysis of hightroughput sequencing data sets. Introns and putative chimeric sequences have been also carefully checked. Taxonomic assignation of sequences...
Tipo: Text
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00114/22492/20174.pdf

Benthic protists: the under-charted majority
Provedor de dados: 5
Autores: Forster, Dominik; Dunthorn, Micah; Mahe, Frederic; Dolan, John R.; Audic, Stephane; Bass, David; Bittner, Lucie; Boutte, Christophe; Christen, Richard; Claverie, Jean-michel; Decelle, Johan; Edvardsen, Bente; Egge, Elianne; Eikrem, Wenche; Gobet, Angelique; Kooistra, Wiebe H. C. F.; Logares, Ramiro; Massana, Ramon; Montresor, Marina; Not, Fabrice; Ogata, Hiroyuki; Pawlowski, Jan; Pernice, Massimo C.; Romac, Sarah; Shalchian-tabrizi, Kamran; Simon, Nathalie; Richards, Thomas A.; Santini, Sebastien; Sarno, Diana; Siano, Raffaele; Vaulot, Daniel; Wincker, Patrick; Zingone, Adriana; De Vargas, Colomban; Stoeck, Thorsten.
Marine protist diversity inventories have largely focused on planktonic environments, while benthic protists have received relatively little attention. We therefore hypothesize that current diversity surveys have only skimmed the surface of protist diversity in marine sediments, which may harbour greater diversity than planktonic environments. We tested this by analyzing sequences of the hypervariable V4 18S rRNA from benthic and planktonic protist communities sampled in European coastal regions. Despite a similar number of OTUs in both realms, richness estimations indicated that we recovered at least 70% of the diversity in planktonic protist communities, but only 33% in benthic communities. There was also little overlap of OTUs between planktonic and...
Tipo: Text
Palavras-chave: Benthic microbial communities; Coastal environments; Protist diversity; High-throughput sequencing.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00341/45233/44658.pdf

Single-cell genomics of multiple uncultured stramenopiles reveals underestimated functional diversity across oceans
Provedor de dados: 5
Autores: Seeleuthner, Yoann; Mondy, Samuel; Lombard, Vincent; Carradec, Quentin; Pelletier, Eric; Wessner, Marc; Leconte, Jade; Mangot, Jean-francois; Poulain, Julie; Labadie, Karine; Logares, Ramiro; Sunagawa, Shinichi; De Berardinis, Veronique; Salanoubat, Marcel; Dimier, Celine; Kandels-lewis, Stefanie; Picheral, Marc; Searson, Sarah; Pesant, Stephane; Poulton, Nicole; Stepanauskas, Ramunas; Bork, Peer; Bowler, Chris; Hingamp, Pascal; Sullivan, Matthew B.; Iudicone, Daniele; Massana, Ramon; Aury, Jean-marc; Henrissat, Bernard; Karsenti, Eric; Jaillon, Olivier; Sieracki, Mike; De Vargas, Colomban; Wincker, Patrick; Tara Oceans Coordinators,.
Single-celled eukaryotes (protists) are critical players in global biogeochemical cycling of nutrients and energy in the oceans. While their roles as primary producers and grazers are well appreciated, other aspects of their life histories remain obscure due to challenges in culturing and sequencing their natural diversity. Here, we exploit single-cell genomics and metagenomics data from the circumglobal Tara Oceans expedition to analyze the genome content and apparent oceanic distribution of seven prevalent lineages of uncultured heterotrophic stramenopiles. Based on the available data, each sequenced genome or genotype appears to have a specific oceanic distribution, principally correlated with water temperature and depth. The genome content provides...
Tipo: Text
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00660/77234/79044.pdf

Diversity patterns and activity of uncultured marine heterotrophic flagellates unveiled with pyrosequencing
Provedor de dados: 5
Autores: Logares, Ramiro; Audic, Stephane; Santini, Sebastien; Pernice, Massimo C.; De Vargas, Colomban; Massana, Ramon.
Flagellated heterotrophic microeukaryotes have key roles for the functioning of marine ecosystems as they channel large amounts of organic carbon to the upper trophic levels and control the population sizes of bacteria and archaea. Still, we know very little on the diversity patterns of most groups constituting this evolutionary heterogeneous assemblage. Here, we investigate 11 groups of uncultured flagellates known as MArine STramenopiles (MASTs). MASTs are ecologically very important and branch at the base of stramenopiles. We explored the diversity patterns of MASTs using pyrosequencing (18S rDNA) in coastal European waters. We found that MAST groups range from highly to lowly diversified. Pyrosequencing (hereafter '454') allowed us to approach to the...
Tipo: Text
Palavras-chave: Diversity; Heterotrophic-flagellates; MAST; Pyrosequencing; Stramenopiles.
Ano: 2012
URL: https://archimer.ifremer.fr/doc/00374/48501/48815.pdf

Molecular diversity and distribution of marine fungi across 130 European environmental samples
Provedor de dados: 5
Autores: Richards, Thomas A.; Leonard, Guy; Mahe, Frederic; Del Campov, Javier; Romac, Sarah; Jones, Meredith D. M.; Maguire, Finlay; Dunthorn, Micah; De Vargas, Colomban; Massana, Ramon; Chambouvet, Aurelie.
Environmental DNA and culture-based analyses have suggested that fungi are present in low diversity and in low abundance in many marine environments, especially in the upper water column. Here, we use a dual approach involving high-throughput diversity tag sequencing from both DNA and RNA templates and fluorescent cell counts to evaluate the diversity and relative abundance of fungi across marine samples taken from six European near-shore sites. We removed very rare fungal operational taxonomic units (OTUs) selecting only OTUs recovered from multiple samples for a detailed analysis. This approach identified a set of 71 fungal 'OTU clusters' that account for 66% of all the sequences assigned to the Fungi. Phylogenetic analyses demonstrated that this...
Tipo: Text
Palavras-chave: 454 pyrosequencing; Chytrids; Dikarya; Sediment communities.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00374/48490/48880.pdf

Marine protist diversity in European coastal waters and sediments as revealed by high-throughput sequencing
Provedor de dados: 5
Autores: Massana, Ramon; Gobet, Angelique; Audic, Stephane; Bass, David; Bittner, Lucie; Boutte, Christophe; Chambouvet, Aurelie; Christen, Richard; Claverie, Jean-michel; Decelle, Johan; Dolan, John R.; Dunthorn, Micah; Edvardsen, Bente; Forn, Irene; Forster, Dominik; Guillou, Laure; Jaillon, Olivier; Kooistra, Wiebe H. C. F.; Logares, Ramiro; Mahe, Frederic; Not, Fabrice; Ogata, Hiroyuki; Pawlowski, Jan; Pernice, Massimo C.; Probert, Ian; Romac, Sarah; Richards, Thomas; Santini, Sebastien; Shalchian-tabrizi, Kamran; Siano, Raffaele; Simon, Nathalie; Stoeck, Thorsten; Vaulot, Daniel; Zingone, Adriana; De Vargas, Colomban.
Although protists are critical components of marine ecosystems, they are still poorly characterized. Here we analysed the taxonomic diversity of planktonic and benthic protist communities collected in six distant European coastal sites. Environmental deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) from three size fractions (pico-, nano- and micro/mesoplankton), as well as from dissolved DNA and surface sediments were used as templates for tag pyrosequencing of the V4 region of the 18S ribosomal DNA. Beta-diversity analyses split the protist community structure into three main clusters: picoplankton-nanoplankton-dissolved DNA, micro/mesoplankton and sediments. Within each cluster, protist communities from the same site and time clustered together,...
Tipo: Text
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00275/38594/37190.pdf

Low Evolutionary Diversification in a Widespread and Abundant Uncultured Protist (MAST-4)
Provedor de dados: 5
Autores: Rodriguez-martinez, Raquel; Rocap, Gabrielle; Logares, Ramiro; Romac, Sarah; Massana, Ramon.
Recent culture-independent studies of marine planktonic protists have unveiled a large diversity at all phylogenetic scales and the existence of novel groups. MAST-4 represents one of these novel uncultured lineages, and it is composed of small (similar to 2 mu m) bacterivorous eukaryotes that are widely distributed in marine systems. MAST-4 accounts for a significant fraction of the marine heterotrophic flagellates at the global level, playing key roles in the marine ecological network. In this study, we investigated the diversity of MAST-4, aiming to assess its limits and structure. Using ribosomal DNA (rDNA) sequences obtained in this study (both pyrosequencing reads and clones with large rDNA operon coverage), complemented with GenBank sequences, we...
Tipo: Text
Palavras-chave: MAST-4; Low evolutionary diversification; Uncultured protist; Pyrosequencing; ITS secondary structure.
Ano: 2012
URL: https://archimer.ifremer.fr/doc/00374/48506/48778.pdf