Adaptive strategies by Southern Ocean phytoplankton to lessen iron limitation: Uptake of organically complexed iron and reduced cellular iron requirements
We report results of laboratory studies examining the effect of low levels of iron (Fe) availability on the intracellular Fe concentrations and specific growth rates in Southern Ocean diatoms (Fragilariopsis kerguelensis, Eucampia antarctica, Proboscia inermis, and Thalassiosira antarctica) and Phae...
Published in: | Limnology and Oceanography |
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Main Authors: | , , , , |
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American Society of Limnology and Oceanography, Inc.
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Online Access: | http://hdl.handle.net/1885/78856 https://doi.org/10.4319/lo.2011.56.6.1983 https://openresearch-repository.anu.edu.au/bitstream/1885/78856/5/Strzepek_R_2011_Adaptive_strategies.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/78856/7/01_Strzepek_Adaptive_strategies_by_2011.pdf.jpg |
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ftanucanberra:oai:openresearch-repository.anu.edu.au:1885/78856 2024-01-14T09:59:26+01:00 Adaptive strategies by Southern Ocean phytoplankton to lessen iron limitation: Uptake of organically complexed iron and reduced cellular iron requirements Strzepek, Robert Maldonado, M T Hunter, K Frew, R Boyd, Phillip http://hdl.handle.net/1885/78856 https://doi.org/10.4319/lo.2011.56.6.1983 https://openresearch-repository.anu.edu.au/bitstream/1885/78856/5/Strzepek_R_2011_Adaptive_strategies.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/78856/7/01_Strzepek_Adaptive_strategies_by_2011.pdf.jpg unknown American Society of Limnology and Oceanography, Inc. 0024-3590 http://hdl.handle.net/1885/78856 doi:10.4319/lo.2011.56.6.1983 https://openresearch-repository.anu.edu.au/bitstream/1885/78856/5/Strzepek_R_2011_Adaptive_strategies.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/78856/7/01_Strzepek_Adaptive_strategies_by_2011.pdf.jpg Limnology and Oceanography Keywords: adaptation alga concentration (composition) diatom growth rate iron laboratory method ligand marine ecosystem nutrient availability nutrient limitation nutrient uptake nutritional requirement phytoplankton siderophore Southern Ocean algae Journal article ftanucanberra https://doi.org/10.4319/lo.2011.56.6.1983 2023-12-15T09:36:09Z We report results of laboratory studies examining the effect of low levels of iron (Fe) availability on the intracellular Fe concentrations and specific growth rates in Southern Ocean diatoms (Fragilariopsis kerguelensis, Eucampia antarctica, Proboscia inermis, and Thalassiosira antarctica) and Phaeocystis antarctica. All species grew on Fe complexed to the siderophore desferrioxamine B (DFB). Concentrations of DFB up to 100-fold in excess of Fe were required to limit growth rates by ≥ 50%. Southern Ocean phytoplankton also grew on Fe complexed by ≥ 10-fold excess concentrations of the siderophores ferrichrome, enterobactin, or aerobactin, whereas the temperate coastal diatoms Thalassiosira weissflogii and Thalassiosira pseudonana did not. Intracellular Fe concentrations and Fe:C ratios of all Southern Ocean species were exceptionally low and decreased with decreasing Fe availability. However, large diatoms had significantly lower cell-volume-normalized Fe content and Fe:C ratios than Phaeocystis. Short-term Fe uptake and extracellular Fe(II) production measurements provided evidence that Phaeocystis possesses a reductive Fe transport pathway. Our findings demonstrate that the largediatom Fe requirements are at least 2-fold lower than currently reported for oceanic algal species and suggest that bioreduction may enable resident phytoplankton to directly use Fe bound to strong organic ligands. Article in Journal/Newspaper Antarc* Antarctica Southern Ocean Australian National University: ANU Digital Collections Southern Ocean Limnology and Oceanography 56 6 1983 2002 |
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Open Polar |
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Australian National University: ANU Digital Collections |
op_collection_id |
ftanucanberra |
language |
unknown |
topic |
Keywords: adaptation alga concentration (composition) diatom growth rate iron laboratory method ligand marine ecosystem nutrient availability nutrient limitation nutrient uptake nutritional requirement phytoplankton siderophore Southern Ocean algae |
spellingShingle |
Keywords: adaptation alga concentration (composition) diatom growth rate iron laboratory method ligand marine ecosystem nutrient availability nutrient limitation nutrient uptake nutritional requirement phytoplankton siderophore Southern Ocean algae Strzepek, Robert Maldonado, M T Hunter, K Frew, R Boyd, Phillip Adaptive strategies by Southern Ocean phytoplankton to lessen iron limitation: Uptake of organically complexed iron and reduced cellular iron requirements |
topic_facet |
Keywords: adaptation alga concentration (composition) diatom growth rate iron laboratory method ligand marine ecosystem nutrient availability nutrient limitation nutrient uptake nutritional requirement phytoplankton siderophore Southern Ocean algae |
description |
We report results of laboratory studies examining the effect of low levels of iron (Fe) availability on the intracellular Fe concentrations and specific growth rates in Southern Ocean diatoms (Fragilariopsis kerguelensis, Eucampia antarctica, Proboscia inermis, and Thalassiosira antarctica) and Phaeocystis antarctica. All species grew on Fe complexed to the siderophore desferrioxamine B (DFB). Concentrations of DFB up to 100-fold in excess of Fe were required to limit growth rates by ≥ 50%. Southern Ocean phytoplankton also grew on Fe complexed by ≥ 10-fold excess concentrations of the siderophores ferrichrome, enterobactin, or aerobactin, whereas the temperate coastal diatoms Thalassiosira weissflogii and Thalassiosira pseudonana did not. Intracellular Fe concentrations and Fe:C ratios of all Southern Ocean species were exceptionally low and decreased with decreasing Fe availability. However, large diatoms had significantly lower cell-volume-normalized Fe content and Fe:C ratios than Phaeocystis. Short-term Fe uptake and extracellular Fe(II) production measurements provided evidence that Phaeocystis possesses a reductive Fe transport pathway. Our findings demonstrate that the largediatom Fe requirements are at least 2-fold lower than currently reported for oceanic algal species and suggest that bioreduction may enable resident phytoplankton to directly use Fe bound to strong organic ligands. |
format |
Article in Journal/Newspaper |
author |
Strzepek, Robert Maldonado, M T Hunter, K Frew, R Boyd, Phillip |
author_facet |
Strzepek, Robert Maldonado, M T Hunter, K Frew, R Boyd, Phillip |
author_sort |
Strzepek, Robert |
title |
Adaptive strategies by Southern Ocean phytoplankton to lessen iron limitation: Uptake of organically complexed iron and reduced cellular iron requirements |
title_short |
Adaptive strategies by Southern Ocean phytoplankton to lessen iron limitation: Uptake of organically complexed iron and reduced cellular iron requirements |
title_full |
Adaptive strategies by Southern Ocean phytoplankton to lessen iron limitation: Uptake of organically complexed iron and reduced cellular iron requirements |
title_fullStr |
Adaptive strategies by Southern Ocean phytoplankton to lessen iron limitation: Uptake of organically complexed iron and reduced cellular iron requirements |
title_full_unstemmed |
Adaptive strategies by Southern Ocean phytoplankton to lessen iron limitation: Uptake of organically complexed iron and reduced cellular iron requirements |
title_sort |
adaptive strategies by southern ocean phytoplankton to lessen iron limitation: uptake of organically complexed iron and reduced cellular iron requirements |
publisher |
American Society of Limnology and Oceanography, Inc. |
url |
http://hdl.handle.net/1885/78856 https://doi.org/10.4319/lo.2011.56.6.1983 https://openresearch-repository.anu.edu.au/bitstream/1885/78856/5/Strzepek_R_2011_Adaptive_strategies.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/78856/7/01_Strzepek_Adaptive_strategies_by_2011.pdf.jpg |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Antarc* Antarctica Southern Ocean |
genre_facet |
Antarc* Antarctica Southern Ocean |
op_source |
Limnology and Oceanography |
op_relation |
0024-3590 http://hdl.handle.net/1885/78856 doi:10.4319/lo.2011.56.6.1983 https://openresearch-repository.anu.edu.au/bitstream/1885/78856/5/Strzepek_R_2011_Adaptive_strategies.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/78856/7/01_Strzepek_Adaptive_strategies_by_2011.pdf.jpg |
op_doi |
https://doi.org/10.4319/lo.2011.56.6.1983 |
container_title |
Limnology and Oceanography |
container_volume |
56 |
container_issue |
6 |
container_start_page |
1983 |
op_container_end_page |
2002 |
_version_ |
1788059154161598464 |