2024-03-28T17:45:57Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1338762022-10-21T07:08:49Zcom_10261_88com_10261_8col_10261_341
The dominant detritus-feeding invertebrate in arctic peat soils derives its essential amino acids from gut symbionts
Larsen, Thomas
Ventura, Marc
Maraldo, Kristine
Triadó-Margarit, Xavier
Casamayor, Emilio O.
Wang, Yiming V.
Andersen, Nils
O'Brien, Diane M.
Supplementation of nutrients by symbionts enables consumers to thrive on resources that might otherwise be insufficient to meet nutritional demands. Such nutritional subsidies by intracellular symbionts has been well studied; however, supplementation of de novo synthesized nutrients to hosts by extracellular gut symbionts is poorly documented, especially for generalists with relatively undifferentiated intestinal tracts.
Although gut symbionts facilitate degradation of resources that would otherwise remain inaccessible to the host, such digestive actions alone cannot make up for dietary insufficiencies of macronutrients such as essential amino acids (EAA). Documenting whether gut symbionts also function as partners for symbiotic EAA supplementation is important because the question of how some detritivores are able to subsist on nutritionally insufficient diets has remained unresolved.
To answer this poorly-understood nutritional aspect of symbiont-host interactions, we studied the enchytraeid worm, a bulk soil feeder that thrives in arctic peatlands. In a combined field and laboratory study, we employed stable isotope fingerprinting of amino acids to identify the biosynthetic origins of amino acids to bacteria, fungi and plants in enchytraeids.
Enchytraeids collected from arctic peatlands derived more than 80% of their EAA from bacteria. In a controlled feeding study with the enchytraeid Enchytraeus crypticus, EAA derived almost exclusively from gut bacteria when the worms fed on higher fiber diets, whereas most of the enchytraeids’ EAA derived from dietary sources when fed on lower fiber diets. Our gene sequencing results of gut microbiota showed that the worms harbor several taxa in their gut lumen absent from their diets and substrates. Almost all gut taxa are candidates for EAA supplementation because almost all belong to clades capable of biosynthesizing EAA.
Our study provides the first evidence of extensive symbiotic supplementation of EAA by microbial gut symbionts, and demonstrate that symbiotic bacteria in the gut lumen appear to function as partners for both symbiotic EAA supplementation as well as for digestion of insoluble plant fibers.
The study was financed by the Danish Council for Independent Research, Technology and
Production Sciences (09-069881), Carlsbergfondet (2007_01_0301) and the National Science
Foundation Grant No. IOB 05–52015 to DO. TL was supported by Juan de la Cierva (JCI-
2009-049330) from the Spanish Office of Science (MINECO) and the DFG‐supported
Cluster of Excellence “The Future Ocean”; MV was supported by the Spanish government
projects Fundalzoo (CGL2010-14841, MINECO), Invasivefish (427/2011) and Biodiversity
Conservation Plan from ENDESA S. A. (6900014499); YW was supported by the DFG -
supported INTERDYNAMIK Research Priority Program SPP1266. Bacterial analyses were
supported by grant DARKNESS (CGL2012-32747, MINECO) to EOC.
Peer reviewed
2016-06-22T08:22:13Z
2016-06-22T08:22:13Z
2016
artículo
http://purl.org/coar/resource_type/c_6501
Journal of Animal Ecology 85(5): 1275-1285 (2016)
0021-8790
http://hdl.handle.net/10261/133876
10.1111/1365-2656.12563
1365-2656
en
Larsen, Thomas; Ventura, Marc; Maraldo, Kristine; Triadó-Margarit, Xavier; Casamayor, Emilio O.; Wang, Yiming V.; Andersen, Nils; O'Brien, Diane M. (2017): Data from: The dominant detritus-feeding invertebrate in arctic peat soils derives its essential amino acids from gut symbionts [Dataset]; Dryad; Version 1; https://doi.org/10.5061/dryad.6f798
http://dx.doi.org/10.1111/1365-2656.12563
Sí
none
Wiley-Blackwell