Dinophyceae can use exudates as weapons against the parasite Amoebophrya sp. (Syndiniales)
|Author(s)||Long Marc1, Marie Dominique2, Szymczak Jeremy2, Toullec Jordan1, Bigeard Estelle2, Sourisseau Marc1, Le Gac Mickael1, Guillou Laure2, Jauzein Cecile1|
|Affiliation(s)||1 : IFREMER, Centre de Brest, DYNECO Pelagos, F-29280, Plouzané, France
2 : UMR 7144 Sorbonne Université & Centre National pour la Recherche Scientifique, «Adaptation and Diversity in Marine Environment», Team «Ecology of Marine Plankton, ECOMAP», Station Biologique de Roscoff, 29680, Roscoff, France
|Source||ISME Communications (2730-6151) (Springer Science and Business Media LLC), 2021-12 , Vol. 1 , N. 1 , P. 34 (10p.)|
|Keyword(s)||Microbial ecology, Plant ecology, Water microbiology|
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.