Saccharides enhance iron bioavailability to Southern Ocean phytoplankton
Iron limits primary productivity in vast regions of the ocean. Given that marine phytoplankton contribute up to 40% of global biological carbon fixation, it is important to understand what parameters control the availability of iron (iron bioavailability) to these organisms. Most studies on iron bio...
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Online Access: | http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3024694 http://www.ncbi.nlm.nih.gov/pubmed/21169217 https://doi.org/10.1073/pnas.1010963108 |
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ftpubmed:oai:pubmedcentral.nih.gov:3024694 2023-05-15T18:25:08+02:00 Saccharides enhance iron bioavailability to Southern Ocean phytoplankton Hassler, Christel S. Schoemann, Véronique Nichols, Carol Mancuso Butler, Edward C. V. Boyd, Philip W. 2011-01-18 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3024694 http://www.ncbi.nlm.nih.gov/pubmed/21169217 https://doi.org/10.1073/pnas.1010963108 en eng National Academy of Sciences http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3024694 http://www.ncbi.nlm.nih.gov/pubmed/21169217 http://dx.doi.org/10.1073/pnas.1010963108 Freely available online through the PNAS open access option. Biological Sciences Text 2011 ftpubmed https://doi.org/10.1073/pnas.1010963108 2013-09-03T10:11:50Z Iron limits primary productivity in vast regions of the ocean. Given that marine phytoplankton contribute up to 40% of global biological carbon fixation, it is important to understand what parameters control the availability of iron (iron bioavailability) to these organisms. Most studies on iron bioavailability have focused on the role of siderophores; however, eukaryotic phytoplankton do not produce or release siderophores. Here, we report on the pivotal role of saccharides—which may act like an organic ligand—in enhancing iron bioavailability to a Southern Ocean cultured diatom, a prymnesiophyte, as well as to natural populations of eukaryotic phytoplankton. Addition of a monosaccharide (>2 nM of glucuronic acid, GLU) to natural planktonic assemblages from both the polar front and subantarctic zones resulted in an increase in iron bioavailability for eukaryotic phytoplankton, relative to bacterioplankton. The enhanced iron bioavailability observed for several groups of eukaryotic phytoplankton (i.e., cultured and natural populations) using three saccharides, suggests it is a common phenomenon. Increased iron bioavailability resulted from the combination of saccharides forming highly bioavailable organic associations with iron and increasing iron solubility, mainly as colloidal iron. As saccharides are ubiquitous, present at nanomolar to micromolar concentrations, and produced by biota in surface waters, they also satisfy the prerequisites to be important constituents of the poorly defined “ligand soup,” known to weakly bind iron. Our findings point to an additional type of organic ligand, controlling iron bioavailability to eukaryotic phytoplankton—a key unknown in iron biogeochemistry. Text Southern Ocean PubMed Central (PMC) Southern Ocean Proceedings of the National Academy of Sciences 108 3 1076 1081 |
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Biological Sciences |
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Biological Sciences Hassler, Christel S. Schoemann, Véronique Nichols, Carol Mancuso Butler, Edward C. V. Boyd, Philip W. Saccharides enhance iron bioavailability to Southern Ocean phytoplankton |
topic_facet |
Biological Sciences |
description |
Iron limits primary productivity in vast regions of the ocean. Given that marine phytoplankton contribute up to 40% of global biological carbon fixation, it is important to understand what parameters control the availability of iron (iron bioavailability) to these organisms. Most studies on iron bioavailability have focused on the role of siderophores; however, eukaryotic phytoplankton do not produce or release siderophores. Here, we report on the pivotal role of saccharides—which may act like an organic ligand—in enhancing iron bioavailability to a Southern Ocean cultured diatom, a prymnesiophyte, as well as to natural populations of eukaryotic phytoplankton. Addition of a monosaccharide (>2 nM of glucuronic acid, GLU) to natural planktonic assemblages from both the polar front and subantarctic zones resulted in an increase in iron bioavailability for eukaryotic phytoplankton, relative to bacterioplankton. The enhanced iron bioavailability observed for several groups of eukaryotic phytoplankton (i.e., cultured and natural populations) using three saccharides, suggests it is a common phenomenon. Increased iron bioavailability resulted from the combination of saccharides forming highly bioavailable organic associations with iron and increasing iron solubility, mainly as colloidal iron. As saccharides are ubiquitous, present at nanomolar to micromolar concentrations, and produced by biota in surface waters, they also satisfy the prerequisites to be important constituents of the poorly defined “ligand soup,” known to weakly bind iron. Our findings point to an additional type of organic ligand, controlling iron bioavailability to eukaryotic phytoplankton—a key unknown in iron biogeochemistry. |
format |
Text |
author |
Hassler, Christel S. Schoemann, Véronique Nichols, Carol Mancuso Butler, Edward C. V. Boyd, Philip W. |
author_facet |
Hassler, Christel S. Schoemann, Véronique Nichols, Carol Mancuso Butler, Edward C. V. Boyd, Philip W. |
author_sort |
Hassler, Christel S. |
title |
Saccharides enhance iron bioavailability to Southern Ocean phytoplankton |
title_short |
Saccharides enhance iron bioavailability to Southern Ocean phytoplankton |
title_full |
Saccharides enhance iron bioavailability to Southern Ocean phytoplankton |
title_fullStr |
Saccharides enhance iron bioavailability to Southern Ocean phytoplankton |
title_full_unstemmed |
Saccharides enhance iron bioavailability to Southern Ocean phytoplankton |
title_sort |
saccharides enhance iron bioavailability to southern ocean phytoplankton |
publisher |
National Academy of Sciences |
publishDate |
2011 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3024694 http://www.ncbi.nlm.nih.gov/pubmed/21169217 https://doi.org/10.1073/pnas.1010963108 |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3024694 http://www.ncbi.nlm.nih.gov/pubmed/21169217 http://dx.doi.org/10.1073/pnas.1010963108 |
op_rights |
Freely available online through the PNAS open access option. |
op_doi |
https://doi.org/10.1073/pnas.1010963108 |
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Proceedings of the National Academy of Sciences |
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108 |
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3 |
container_start_page |
1076 |
op_container_end_page |
1081 |
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1766206354940231680 |