Figure S5 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts
The symbiotic planktonic foraminifera Orbulina universa inhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed that O. universa meets its nitrogen (N) requirements by preying on zooplankton, and that i...
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ftroysocietyfig:oai:figshare.com:article/12470273 2023-05-15T18:00:42+02:00 Figure S5 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts Charlotte LeKieffre Howard J. Spero Jennifer S. Fehrenbacher Ann D. Russell Haojia Ren Emmanuelle Geslin Anders Meibom 2020-06-12T03:17:04Z https://doi.org/10.6084/m9.figshare.12470273.v1 https://figshare.com/articles/journal_contribution/Figure_S5_from_Ammonium_is_the_preferred_source_of_nitrogen_for_planktonic_foraminifer_and_their_dinoflagellate_symbionts/12470273 unknown doi:10.6084/m9.figshare.12470273.v1 https://figshare.com/articles/journal_contribution/Figure_S5_from_Ammonium_is_the_preferred_source_of_nitrogen_for_planktonic_foraminifer_and_their_dinoflagellate_symbionts/12470273 CC BY 4.0 CC-BY Microbiology Ecology Palaeontology (incl. Palynology) planktonic foraminifera dinoflagellate symbiosis ammonium assimilation ammonium recycling photosymbiosis Text Journal contribution 2020 ftroysocietyfig https://doi.org/10.6084/m9.figshare.12470273.v1 2022-01-01T19:30:31Z The symbiotic planktonic foraminifera Orbulina universa inhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed that O. universa meets its nitrogen (N) requirements by preying on zooplankton, and that its symbiotic dinoflagellates recycle metabolic ‘waste ammonium’ for their N pool. However, these conclusions were derived from bulk 15 N-enrichment experiments and model calculations, and our understanding of N assimilation and exchange between the foraminifer host cell and its symbiotic dinoflagellates remains poorly constrained. Here, we present data from pulse-chase experiments with 13 C-enriched inorganic carbon, 15 N-nitrate and 15 N-ammonium, as well as a 13 C- and 15 N- enriched heterotrophic food source, followed by TEM coupled to NanoSIMS isotopic imaging to visualize and quantify C and N assimilation and translocation in the symbiotic system. High levels of 15 N-labelling were observed in the dinoflagellates and in foraminiferal organelles and cytoplasm after incubation with 15 N-ammonium, indicating efficient ammonium assimilation. Only weak 15 N-assimilation was observed after incubation with 15 N-nitrate. Feeding foraminifers with 13 C- and 15 N-labelled food resulted in dinoflagellates that were labelled with 15 N, thereby confirming the transfer of 15 N-compounds from the digestive vacuoles of the foraminifer to the symbiotic dinoflagellates, likely through recycling of ammonium. These observations are important for N isotope-based paleoceanographic reconstructions, as they show that δ 15 N values recorded in the organic matrix in symbiotic species likely reflect ammonium recycling rather than alternative N sources, such as nitrates. Other Non-Article Part of Journal/Newspaper Planktonic foraminifera The Royal Society: Figshare |
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Open Polar |
collection |
The Royal Society: Figshare |
op_collection_id |
ftroysocietyfig |
language |
unknown |
topic |
Microbiology Ecology Palaeontology (incl. Palynology) planktonic foraminifera dinoflagellate symbiosis ammonium assimilation ammonium recycling photosymbiosis |
spellingShingle |
Microbiology Ecology Palaeontology (incl. Palynology) planktonic foraminifera dinoflagellate symbiosis ammonium assimilation ammonium recycling photosymbiosis Charlotte LeKieffre Howard J. Spero Jennifer S. Fehrenbacher Ann D. Russell Haojia Ren Emmanuelle Geslin Anders Meibom Figure S5 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts |
topic_facet |
Microbiology Ecology Palaeontology (incl. Palynology) planktonic foraminifera dinoflagellate symbiosis ammonium assimilation ammonium recycling photosymbiosis |
description |
The symbiotic planktonic foraminifera Orbulina universa inhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed that O. universa meets its nitrogen (N) requirements by preying on zooplankton, and that its symbiotic dinoflagellates recycle metabolic ‘waste ammonium’ for their N pool. However, these conclusions were derived from bulk 15 N-enrichment experiments and model calculations, and our understanding of N assimilation and exchange between the foraminifer host cell and its symbiotic dinoflagellates remains poorly constrained. Here, we present data from pulse-chase experiments with 13 C-enriched inorganic carbon, 15 N-nitrate and 15 N-ammonium, as well as a 13 C- and 15 N- enriched heterotrophic food source, followed by TEM coupled to NanoSIMS isotopic imaging to visualize and quantify C and N assimilation and translocation in the symbiotic system. High levels of 15 N-labelling were observed in the dinoflagellates and in foraminiferal organelles and cytoplasm after incubation with 15 N-ammonium, indicating efficient ammonium assimilation. Only weak 15 N-assimilation was observed after incubation with 15 N-nitrate. Feeding foraminifers with 13 C- and 15 N-labelled food resulted in dinoflagellates that were labelled with 15 N, thereby confirming the transfer of 15 N-compounds from the digestive vacuoles of the foraminifer to the symbiotic dinoflagellates, likely through recycling of ammonium. These observations are important for N isotope-based paleoceanographic reconstructions, as they show that δ 15 N values recorded in the organic matrix in symbiotic species likely reflect ammonium recycling rather than alternative N sources, such as nitrates. |
format |
Other Non-Article Part of Journal/Newspaper |
author |
Charlotte LeKieffre Howard J. Spero Jennifer S. Fehrenbacher Ann D. Russell Haojia Ren Emmanuelle Geslin Anders Meibom |
author_facet |
Charlotte LeKieffre Howard J. Spero Jennifer S. Fehrenbacher Ann D. Russell Haojia Ren Emmanuelle Geslin Anders Meibom |
author_sort |
Charlotte LeKieffre |
title |
Figure S5 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts |
title_short |
Figure S5 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts |
title_full |
Figure S5 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts |
title_fullStr |
Figure S5 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts |
title_full_unstemmed |
Figure S5 from Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts |
title_sort |
figure s5 from ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts |
publishDate |
2020 |
url |
https://doi.org/10.6084/m9.figshare.12470273.v1 https://figshare.com/articles/journal_contribution/Figure_S5_from_Ammonium_is_the_preferred_source_of_nitrogen_for_planktonic_foraminifer_and_their_dinoflagellate_symbionts/12470273 |
genre |
Planktonic foraminifera |
genre_facet |
Planktonic foraminifera |
op_relation |
doi:10.6084/m9.figshare.12470273.v1 https://figshare.com/articles/journal_contribution/Figure_S5_from_Ammonium_is_the_preferred_source_of_nitrogen_for_planktonic_foraminifer_and_their_dinoflagellate_symbionts/12470273 |
op_rights |
CC BY 4.0 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.6084/m9.figshare.12470273.v1 |
_version_ |
1766169896970878976 |