@article {long_dinophyceae_2021,
	title = {Dinophyceae can use exudates as weapons against the parasite Amoebophrya sp. (Syndiniales)},
	journal = {ISME Communications},
	volume = {1},
	number = {1},
	year = {2021},
	note = {Bandiera_abtest: a Cg_type: Nature Research Journals Number: 1 Primary_atype: Research Publisher: Nature Publishing Group Subject_term: Microbial ecology;Plant ecology;Water microbiology Subject_term_id: microbial-ecology;plant-ecology;water-microbiology},
	pages = {1{\textendash}10},
	abstract = {Parasites in the genus Amoebophrya sp. infest dinoflagellate hosts in marine ecosystems and can be determining factors in the demise of blooms, including toxic red tides. These parasitic protists, however, rarely cause the total collapse of Dinophyceae blooms. Experimental addition of parasite-resistant Dinophyceae (Alexandrium minutum or Scrippsiella donghaienis) or exudates into a well-established host-parasite coculture (Scrippsiella acuminata-Amoebophrya sp.) mitigated parasite success and increased the survival of the sensitive host. This effect was mediated by waterborne molecules without the need for a physical contact. The strength of the parasite defenses varied between dinoflagellate species, and strains of A. minutum and was enhanced with increasing resistant host cell concentrations. The addition of resistant strains or exudates never prevented the parasite transmission entirely. Survival time of Amoebophrya sp. free-living stages (dinospores) decreased in presence of A. minutum but not of S. donghaienis. Parasite progeny drastically decreased with both species. Integrity of the dinospore membrane was altered by A. minutum, providing a first indication on the mode of action of anti-parasitic molecules. These results demonstrate that extracellular defenses can be an effective strategy against parasites that protects not only the resistant cells producing them, but also the surrounding community.},
	keywords = {microbial ecology, Plant ecology, rcc, RCC1627, RCC4383, RCC4714, RCC749, Water microbiology},
	issn = {2730-6151},
	doi = {10.1038/s43705-021-00035-x},
	url = {http://www.nature.com/articles/s43705-021-00035-x},
	author = {Long, Marc and Marie, Dominique and Szymczak, Jeremy and Toullec, Jordan and Bigeard, Estelle and Sourisseau, Marc and Le Gac, Micka{\"e}l and Guillou, Laure and Jauzein, C{\'e}cile}
}
@article {geffroy_sxta4_2021,
	title = {From the sxtA4 Gene to Saxitoxin Production: What Controls the Variability Among Alexandrium minutum and Alexandrium pacificum Strains?},
	journal = {Frontiers in Microbiology},
	volume = {12},
	year = {2021},
	pages = {613199},
	abstract = {Paralytic shellfish poisoning (PSP) is a human foodborne syndrome caused by the consumption of shellfish that accumulate paralytic shellfish toxins (PSTs, saxitoxin group). In PST-producing dinoflagellates such as Alexandrium spp., toxin synthesis is encoded in the nuclear genome via a gene cluster (sxt). Toxin production is supposedly associated with the presence of a 4th domain in the sxtA gene (sxtA4), one of the core genes of the PST gene cluster. It is postulated that gene expression in dinoflagellates is partially constitutive, with both transcriptional and post-transcriptional processes potentially co-occurring. Therefore, gene structure and expression mode are two important features to explore in order to fully understand toxin production processes in dinoflagellates. In this study, we determined the intracellular toxin contents of twenty European Alexandrium minutum and Alexandrium pacificum strains that we compared with their genome size and sxtA4 gene copy numbers. We observed a significant correlation between the sxtA4 gene copy number and toxin content, as well as a moderate positive correlation between the sxtA4 gene copy number and genome size. The 18 toxic strains had several sxtA4 gene copies (9{\textendash}187), whereas only one copy was found in the two observed non-toxin producing strains. Exploration of allelic frequencies and expression of sxtA4 mRNA in 11 A. minutum strains showed both a differential expression and specific allelic forms in the non-toxic strains compared with the toxic ones. Also, the toxic strains exhibited a polymorphic sxtA4 mRNA sequence between strains and between gene copies within strains. Finally, our study supported the hypothesis of a genetic determinism of toxin synthesis (i.e., the existence of several genetic isoforms of the sxtA4 gene and their copy numbers), and was also consistent with the hypothesis that constitutive gene expression and moderation by transcriptional and post-transcriptional regulation mechanisms are the cause of the observed variability in the production of toxins by A. minutum.},
	keywords = {RCC2644, RCC2645, RCC3327, RCC4871, RCC4872, RCC4890, RCC7037, RCC7038, RCC7039},
	issn = {1664-302X},
	doi = {10.3389/fmicb.2021.613199},
	url = {https://www.frontiersin.org/articles/10.3389/fmicb.2021.613199/full},
	author = {Geffroy, Sol{\`e}ne and Lechat, Marc-Marie and Le Gac, Micka{\"e}l and Rovillon, Georges-Augustin and Marie, Dominique and Bigeard, Estelle and Malo, Florent and Amzil, Zouher and Guillou, Laure and Caruana, Amandine M. N.}
}
@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}
}
