Some mixotrophic flagellate species selectively graze on Archaea
Ballen-Segura, Miguel (Centre d'Estudis Avançats de Blanes)
Felip, Marisol (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Catalán, Jordi (Centre de Recerca Ecològica i d'Aplicacions Forestals)

Date:	2017
Abstract:	Many phototrophic flagellates ingest prokaryotes. This mixotrophic trait becomes a critical aspect of the microbial loop in planktonic food webs because of the typical high abundance of these flagellates. Our knowledge of their selective feeding upon different groups of prokaryotes, particularly under field conditions, is still quite limited. In this study, we investigated the feeding behavior of three species (Rhodomonas sp. , Cryptomonas ovata, and Dinobryon cylindricum) via their food vacuole content in field populations of a high mountain lake. We used the catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH) protocol with probes specific for the domain Archaea and three groups of Eubacteria: Betaproteobacteria, Actinobacteria, and Cytophaga-Flavobacteria of Bacteroidetes. Our results provide field evidence that contrasting selective feeding exists between coexisting mixotrophic flagellates under the same environmental conditions and that some prokaryotic groups may be preferentially impacted by phagotrophic pressure in aquatic microbial food webs. In our study, Archaea were the preferred prey, chiefly in the case of Rhodomonas sp. , which rarely fed on any other prokaryotic group. In general, prey selection did not relate to prey size among the grazed groups. However, Actinobacteria, which were clearly avoided, mostly showed a size of <0. 5 μm, markedly smaller than cells from the other groups.
Grants:	Ministerio de Educación y Ciencia CGL2007-64177/BO Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-1249
Note:	Altres ajuts: Spanish Ministry of the Environment project EGALA (OAPN-124/2010)
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Archaea ; Mixotrophic protist ; Selective feeding
Published in:	Applied and environmental microbiology, Vol. 83, issue 2 (Jan. 2017) , e02317-e02318, ISSN 0099-2240

DOI: 10.1128/AEM.02317-16
PMID: 27815273

Post-print. Article 31 p, 889.3 KB

Post-print. Material addicional 1 p, 115.8 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > CREAF (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Articles > Research articles
Articles > Published articles