@article {ruan_different_2023, title = {Different photosynthetic responses of haploid and diploid Emiliania huxleyi (Prymnesiophyceae) to high light and ultraviolet radiation}, journal = {Bioresources and Bioprocessing}, volume = {10}, number = {1}, year = {2023}, month = {jul}, pages = {40}, abstract = {Solar radiation varies quantitatively and qualitatively while penetrating through the seawater column and thus is one of the most important environmental factors shaping the vertical distribution pattern of phytoplankton. The haploid and diploid life-cycle phases of coccolithophores might have different vertical distribution preferences. Therefore, the two phases respond differently to high solar photosynthetically active radiation (PAR, 400{\textendash}700~nm) and ultraviolet radiation (UVR, 280{\textendash}400~nm). To test this, the haploid and diploid Emiliania huxleyi were exposed to oversaturating irradiance. In the presence of PAR alone, the effective quantum yield was reduced by 10\% more due to the higher damage rate of photosystem II in haploid cells than in diploid cells. The addition of UVR resulted in further inhibition of the quantum yield for both haploid and diploid cells in the first 25~min, partly because of the increased damage of photosystem II. Intriguingly, this UVR-induced inhibition of the haploid cells completely recovered half an hour later. This recovery was confirmed by the comparable maximum quantum yields, maximum relative electron transport rates and yields of the haploid cells treated with PAR and PAR + UVR. Our data indicated that photosynthesis of the haploid phase was more sensitive to high visible light than the diploid phase but resistant to UVR-induced inhibition, reflecting the ecological niches to which this species adapts.}, keywords = {Diploid phase, Effective quantum yield, Emiliania huxleyi, Haploid phase, rcc1217, Ultraviolet radiation (UVR)}, issn = {2197-4365}, doi = {10.1186/s40643-023-00660-5}, url = {https://doi.org/10.1186/s40643-023-00660-5}, author = {Ruan, Zuoxi and Lu, Meifang and Lin, Hongmin and Chen, Shanwen and Li, Ping and Chen, Weizhou and Xu, Huijuan and Qiu, Dajun} } @article {schapira_les_2021, title = {Les Efflorescences de Lepidodinium chlorophorum au large de la Loire et de la Vilaine : D{\'e}terminisme et cons{\'e}quences sur la qualit{\'e} des masses d{\textquoteright}eau c{\^o}ti{\`e}res}, year = {2021}, abstract = {Ce projet, organis{\'e} en trois actions, avait pour objectif de mieux {\'e}valuer les risques d{\textquoteright}eaux color{\'e}es vertes se produisant sur le secteur c{\^o}tier situ{\'e} au large de la Loire et de la Vilaine, en termes (i) de fr{\'e}quence de ces {\'e}pisodes, (ii) d{\textquoteright}abondance et (iii) de localisation des zones {\`a} risque. Action 1 : Am{\'e}lioration du recensement des eaux vertes {\`a} L. chlorophorum Action 2 : Optimisation de l{\textquoteright}estimation des abondances de L. chlorophorum Action 3 : Identification des zones {\`a} risque au large de la Loire et de la Vilaine.}, keywords = {? No DOI found, rcc, RCC1489}, url = {https://archimer.ifremer.fr/doc/00724/83598/}, author = {Schapira, Mathilde and Roux, Pauline and Andre, Coralie and Mertens, Kenneth and Bilien, Gwenael and Terre Terrillon, Aouregan and Le Gac-Abernot, Chantal and Siano, Raffaele and Qu{\'e}r{\'e}, Julien and Bizzozero, Lucie and Bonneau, Francoise and Bouget, Jean-Francois and Cochennec-Laureau, Nathalie and Collin, Karine and Fortune, Mireille and Gabellec, Raoul and Le Merrer, Yoann and Manach, Soazig and Pierre-Duplessix, Olivier and Retho, Michael and Schmitt, Anne and Souchu, Philippe and Stachowski-Haberkorn, Sabine} } @article {wang_moderating_2021, title = {The moderating role of population succession in the adaptive responses of Synechococcus assemblages: evidence from light intensity simulation experiment}, journal = {Photosynthetica}, volume = {59}, number = {4}, year = {2021}, pages = {587{\textendash}599}, abstract = {Synechococcus is one of the most abundant photoautotrophic picoplankton in the marine ecosystem. However, it is not clear how Synechococcus assemblages respond to light intensity variation in a genus group. Here, enriched Synechococcus assemblages from in situ coastal seawater were subjected to light intensity simulation experiments in a range of 9-243 μmol(photon) m{\textendash}2 s{\textendash}1. Characteristics concerning physiology, genomics, and metatranscriptomics were analyzed. Physiologically, the fitting model predicted photosynthesis indications and pigment contents increased with different trends following the light intensity. Genomic sequencing demonstrated that both the phylogenetic and phenotypic compositions of Synechococcus assemblage exhibited population succession. Especially, the proportion of Synechococcus pigment type 2 was changed significantly. In metatranscriptomics, most genes were downregulated in the high-light intensity group, while photosynthesis-related genes were entirely upregulated. The high upregulation of photosynthesis-related genes, such as psbO, psbA, apcB, and cpcB, corresponded to the succession of Synechococcus genotype and was responsible for the physiological shift in response to light intensity.}, issn = {03003604, 15739058}, doi = {10.32615/ps.2021.050}, url = {http://ps.ueb.cas.cz/doi/10.32615/ps.2021.050.html}, author = {Wang, T. and Chen, X. and Li, J.L. and Qin, S. and Cui, Y.L. and Xu, F.} } @article {Bretherton2020, title = {Trait-dependent variability of the response of marine phytoplankton to oil and dispersant exposure}, journal = {Marine Pollution Bulletin}, volume = {153}, number = {January}, year = {2020}, note = {Publisher: Elsevier tex.mendeley-tags: RCC1614}, pages = {110906}, abstract = {The Deepwater Horizon oil spill released millions of barrels of crude oil into the Gulf of Mexico, and saw widespread use of the chemical dispersant Corexit. We assessed the role of traits, such as cell size, cell wall, motility, and mixotrophy on the growth and photosynthetic response of 15 phytoplankton taxa to oil and Corexit. We collected growth and photosynthetic data on five algal cultures. These responses could be separated into resistant (Tetraselmis astigmatica, Ochromonas sp., Heterocapsa pygmaea) and sensitive (Micromonas pusilla, Prorocentrum minimum). We combined this data with 10 species previously studied and found that cell size is most important in determining the biomass response to oil, whereas motility/mixotrophy is more important in the dispersed oil. Our analysis accounted for a third of the variance observed, so further work is needed to identify other factors that contribute to oil resistance.}, keywords = {Chemical dispersants, Chlorophyll, crude oil, Photosynthesis, phytoplankton, RCC1614, Trait-based analysis}, issn = {18793363}, doi = {10.1016/j.marpolbul.2020.110906}, url = {https://doi.org/10.1016/j.marpolbul.2020.110906}, author = {Bretherton, Laura and Hillhouse, Jessica and Kamalanathan, Manoj and Finkel, Zoe V. and Irwin, Andrew J. and Quigg, Antonietta} } @article {Klouch2016, title = {Historical records from dated sediment cores reveal the multidecadal dynamic of the toxic dinoflagellate Alexandrium minutum in the Bay of Brest (France)}, journal = {FEMS Microbiology Ecology}, volume = {92}, number = {7}, year = {2016}, note = {tex.mendeley-tags: 2016,rcc,sbr?hyto$_\textrmd$ipo}, month = {jul}, pages = {fiw101}, abstract = {The multiannual dynamic of the cyst-forming and toxic marine dinoflagellate Alexandrium minutum was studied over a time scale of about 150 years by a paleoecological approach based on ancient DNA (aDNA) quantification and cyst revivification data obtained from two dated sediment cores of the Bay of Brest (Brittany, France). The first genetic traces of the species presence in the study area dated back to 1873 {\textpm} 6. Specific aDNA could be quantified by a newly-developed real-time PCR assay in the upper core layers, in which the germination of the species (in up to 17-19 year-old sediments) was also obtained. In both cores studied, our quantitative paleogenetic data showed a statistically significant increasing trend in the abundance of A. minutum ITS1 rDNA copies over time, corroborating three decades of local plankton data that have documented an increasing trend in the species cell abundance. By comparison, paleogenetic data of the dinoflagellate Scrippsiella donghaienis did not show a coherent trend between the cores studied, supporting the hypothesis of the existence of a species-specific dynamic of A. minutum in the study area. This work contributes to the development of paleoecological research, further showing its potential for biogeographical, ecological and evolutionary studies on marine microbes.}, keywords = {2016, rcc, sbr?hyto$_\textrmd$ipo}, issn = {1574-6941}, doi = {10.1093/femsec/fiw101}, url = {http://www.ncbi.nlm.nih.gov/pubmed/27162179 https://academic.oup.com/femsec/article-lookup/doi/10.1093/femsec/fiw101}, author = {Klouch, Khadidja Z and Schmidt, Sabine and Andrieux-Loyer, Fran{\c c}oise and Le Gac, Micka{\"e}l and Hervio-Heath, Dominique and Qui-Minet, Zujaila N and Qu{\'e}r{\'e}, Julien and Bigeard, Estelle and Guillou, Laure and Siano, Raffaele}, editor = {Laanbroek, Riks} } @article {Nezan2014, title = {Genetic diversity of the harmful family Kareniaceae (Gymnodiniales, Dinophyceae) in France, with the description of {\textexclamdown}i{\textquestiondown}Karlodinium gentienii{\textexclamdown}/i{\textquestiondown} sp. nov.: A new potentially toxic dinoflagellate}, journal = {Harmful Algae}, volume = {40}, year = {2014}, note = {tex.mendeley-tags: 2014,rcc,sbr?hyto?app}, pages = {75{\textendash}91}, abstract = {A B S T R A C T The family Kareniaceae is mostly known in France for recurrent blooms of Karenia mikimotoi in the Atlantic, English Channel, and Mediterranean Sea and for the unusual green discoloration in the saltwater lagoon of Diana (Corsica) caused by Karlodinium corsicum in April 1994. In terms of diversity, this taxonomic group was long overlooked owing to the difficult identification of these small unarmored dinoflagellates. In this study, thanks to the molecular characterization performed on single cells from field samples and cultures, twelve taxonomic units were assigned to the known genera Karenia, Karlodinium and Takayama, whereas one could not be affiliated to any described genus. The molecular phylogeny inferred from the D1{\textendash}D2 region of the LSU rDNA showed that five of them formed a sister taxon of a known species, and could not be identified at species-level, on the basis of molecular analysis only. Among these latter taxa, one Karlodinium which was successfully cultured was investigated by studying the external morphological features (using two procedures for cells fixation), ultrastructure, pigment composition, and haemolytic activity. The results of our analyses corroborate the genetic results in favour of the erection of Karlodinium gentienii sp. nov., which possesses an internal complex system of trichocysts connected to external micro-processes particularly abundant in the epicone, and a peculiar pigment composition. In addition, preliminary assays showed a haemolytic activity.}, keywords = {2014, rcc, sbr?hyto?app}, issn = {15689883}, doi = {10.1016/j.hal.2014.10.006}, url = {http://linkinghub.elsevier.com/retrieve/pii/S1568988314001863}, author = {N{\'e}zan, Elisabeth and Siano, Raffaele and Boulben, Sylviane and Six, Christophe and Bilien, Gwenael and Ch{\`e}ze, Karine and Duval, Audrey and Le Panse, Sophie and Qu{\'e}r{\'e}, Julien and Chom{\'e}rat, Nicolas} } @article {chen_genetic_2013, title = {Genetic transformation of marine cyanobacterium Synechococcus sp. CC9311 (Cyanophyceae) by electroporation}, journal = {Chinese Journal of Oceanology and Limnology}, volume = {31}, number = {2}, year = {2013}, pages = {416{\textendash}420}, abstract = {Synechococcus sp. CC9311 is a marine cyanobacterium characterized by type IV chromatic acclimation (CA). A genetic transformation system was developed as a first step to elucidate the molecular mechanism of CA. The results show that Synechococcus sp. CC9311 cells were sensitive to four commonly used antibiotics: ampicillin, kanamycin, spectinomycin, and chloramphenicol. An integrative plasmid to disrupt the putative phycoerythrin lyase gene mpeV, using a kanamycin resistance gene as selectable marker, was constructed by recombinant polymerase chain reaction. The plasmid was then transformed into Synechococcus sp. CC9311 via electroporation. High transformation efficiency was achieved at a field strength of 2 kV/cm. DNA analysis showed that mpeV was fully disrupted following challenge of the transformants with a high concentration of kanamycin. In addition, the transformants that displayed poor growth on agar SN medium could be successfully plated on agarose SN medium.}, keywords = {RCC1086}, issn = {1993-5005}, doi = {10.1007/s00343-013-2164-5}, url = {https://doi.org/10.1007/s00343-013-2164-5}, author = {Chen, Huaxin and Lin, Hanzhi and Jiang, Peng and Li, Fuchao and Qin, Song} } @article {Descles2008, title = {New tools for labeling silica in living diatoms}, journal = {New Phytologist}, volume = {177}, number = {3}, year = {2008}, note = {ISBN: 0028-646X tex.mendeley-tags: rcc}, pages = {822{\textendash}829}, abstract = {Silicon biomineralization is a widespread mechanism found in several kingdoms that concerns both unicellular and multicellular organisms. As a result of genomic and molecular tools, diatoms have emerged as a good model for biomineralization studies and have provided most of the current knowledge on this process. However, the number of techniques available to study its dynamics at the cellular level is still rather limited. Here, new probes were developed specifically to label the pre-existing or the newly synthesized silica frustule of several diatoms species. It is shown that the LysoTracker Yellow HCK-123, which can be used to visualize silica frustules with common filter sets, presents an enhanced signal-to-noise ratio and allows details of the frustules to be imaged without of the use of ionophores. It is also demonstrated that methoxysilane derivatives can be coupled to fluorescein-5-isothiocyanate (FITC) to preferentially label the silica components of living cells. The coupling of labeling procedures might help to address the challenging question of the process of frustule exocytosis.}, keywords = {3D-imaging, BACILLARIOPHYCEAE, BIOLOGY, biomineralization, DEPOSITION, diatoms, exocytosis, FLUORESCENT, nanopattern, pH, phaeodactylum-tricornutum, PLANTS, rcc, THALASSIOSIRA-PSEUDONANA, ultrastructure, VESICLE}, doi = {10.1111/j.1469-8137.2007.02303.x}, author = {Descles, J and Vartanian, M and El Harrak, A and Quinet, M and Bremond, N and Sapriel, G and Bibette, J and Lopez, P J} } @article {Fawley2000, title = {Phylogenetic analyses of 18S rDNA sequences reveal a new coccoid lineage of the Prasinophyceae (Chlorophyta)}, journal = {Journal of Phycology}, volume = {36}, number = {2}, year = {2000}, note = {ISBN: 0022-3646 Publisher: Phycological Soc Amer Inc tex.address: 810 East 10Th St, Lawrence, KS 66044, USA tex.mendeley-tags: RCC,rcc}, pages = {387{\textendash}393}, abstract = {Phylogenetic analyses of 18S rDNA sequences from 25 prasinophytes, including 10 coccoid isolates, reveals that coccoid organisms are-found in at least three prasinophyte lineages, The coccoid Ostreococcus tauri is included in the Mamiellales lineage and Pycnococcus provasolii is allied with the f dfellate Pseudoscourfieldia marina. A previously undescribed prasinophyte lineage is comprised of the coccoid Prasinococcus cf. Capsulatus (CCMP 1407) and other isolates tentatively identified as Prasinococcussp. (CCMP 1202, CCMP 1614, and CCMP 1194), as well as three unnamed coccoids (CCMP 1193, CCMP 1413, and CCMP 1220). No flagellate organisms are known from this lineage. Organisms of this new lineage share some characteristics of both the Pycnococcaceae and the Mamiellales, although relationships among these separate lineages were not supported by bootstrap analyses. An additional unnamed coccoid isolate (CCMP 1205) is separate from all major prasinophyte lineages. The analyses did not resolve the relationships among the major prasinophyte lineages, although they support previous conclusions that the Prasinophyceae are not monophyletic.}, keywords = {ALGAL CAROTENOIDS, coccoid algae, EVOLUTIONARY TREES, Gen, GREEN-ALGAE, LIGHT-HARVESTING COMPLEX, MICROMONADOPHYCEAE CHLOROPHYTA, Prasinophyceae, PRASINOXANTHIN, PSEUDOSCOURFIELDIA-MARINA, rcc, RDNA, RIBOSOMAL-RNA SEQUENCES, Sequence Analysis, sp-nov}, doi = {10.1046/j.1529-8817.2000.99105.x}, author = {Fawley, M W and Yun, Y and Qin, M} }