Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell Sorting
Marine phytoplankton play a central role in global biogeochemical cycling, carbon export, and the overall functioning of marine ecosystems. While chlorophyll a (Chl a) is widely used as a proxy for phytoplankton biomass, identifying the proportion of Chl a attributable to different phytoplankton gro...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-05-01
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| Series: | Frontiers in Marine Science |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fmars.2022.850646/full |
| _version_ | 1811255678937858048 |
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| author | Nicholas Bock Ajit Subramaniam Andrew R. Juhl Joseph Montoya Solange Duhamel |
| author_facet | Nicholas Bock Ajit Subramaniam Andrew R. Juhl Joseph Montoya Solange Duhamel |
| author_sort | Nicholas Bock |
| collection | DOAJ |
| description | Marine phytoplankton play a central role in global biogeochemical cycling, carbon export, and the overall functioning of marine ecosystems. While chlorophyll a (Chl a) is widely used as a proxy for phytoplankton biomass, identifying the proportion of Chl a attributable to different phytoplankton groups remains a major challenge in oceanography, especially for the picophytoplankton groups that often represent the majority of phytoplankton biomass in the open ocean. We describe a method for measuring picophytoplankton per-cell Chl a in field samples using fluorescence-activated cell sorting followed by solvent-based Chl a extraction and fluorescence quantification. Applying this method to surface samples from the Gulf of Mexico, we determined per-cell Chl a to be 0.24 ± 0.07, 0.6 ± 0.33, and 26.36 ± 20.9 fg Chl a cell-1 for Prochlorococcus, Synechococcus, and PPE, respectively (mean ± SD). Measurements of per-cell Chl a using this method are precise to within 1.7, 2.1, and 3.1% for Prochlorococcus, Synechococcus, and PPE, respectively. We demonstrate that this approach can be used to obtain estimates of group-specific Chl a for Prochlorococcus, Synechococcus, and picophytoeukaryotes, the latter two of which cannot be captured by existing methods. We also demonstrate that measurements of per-cell Chl a made using this method in field samples are sufficiently precise to capture relationships between per-cell Chl a and cytometer red fluorescence, providing a bridge between biomass estimates from cell counts and bulk measurements of total Chl a. |
| first_indexed | 2024-04-12T17:27:47Z |
| format | Article |
| id | doaj.art-d0ee2f12c76d423ba93f90a3bbb73f72 |
| institution | Directory Open Access Journal |
| issn | 2296-7745 |
| language | English |
| last_indexed | 2024-04-12T17:27:47Z |
| publishDate | 2022-05-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Marine Science |
| spelling | doaj.art-d0ee2f12c76d423ba93f90a3bbb73f722022-12-22T03:23:15ZengFrontiers Media S.A.Frontiers in Marine Science2296-77452022-05-01910.3389/fmars.2022.850646850646Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell SortingNicholas Bock0Ajit Subramaniam1Andrew R. Juhl2Joseph Montoya3Solange Duhamel4Lamont-Doherty Earth Observatory, Division of Biology and Paleo Environment, Columbia University, Palisades, NY, United StatesLamont-Doherty Earth Observatory, Division of Biology and Paleo Environment, Columbia University, Palisades, NY, United StatesLamont-Doherty Earth Observatory, Division of Biology and Paleo Environment, Columbia University, Palisades, NY, United StatesSchool of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United StatesLamont-Doherty Earth Observatory, Division of Biology and Paleo Environment, Columbia University, Palisades, NY, United StatesMarine phytoplankton play a central role in global biogeochemical cycling, carbon export, and the overall functioning of marine ecosystems. While chlorophyll a (Chl a) is widely used as a proxy for phytoplankton biomass, identifying the proportion of Chl a attributable to different phytoplankton groups remains a major challenge in oceanography, especially for the picophytoplankton groups that often represent the majority of phytoplankton biomass in the open ocean. We describe a method for measuring picophytoplankton per-cell Chl a in field samples using fluorescence-activated cell sorting followed by solvent-based Chl a extraction and fluorescence quantification. Applying this method to surface samples from the Gulf of Mexico, we determined per-cell Chl a to be 0.24 ± 0.07, 0.6 ± 0.33, and 26.36 ± 20.9 fg Chl a cell-1 for Prochlorococcus, Synechococcus, and PPE, respectively (mean ± SD). Measurements of per-cell Chl a using this method are precise to within 1.7, 2.1, and 3.1% for Prochlorococcus, Synechococcus, and PPE, respectively. We demonstrate that this approach can be used to obtain estimates of group-specific Chl a for Prochlorococcus, Synechococcus, and picophytoeukaryotes, the latter two of which cannot be captured by existing methods. We also demonstrate that measurements of per-cell Chl a made using this method in field samples are sufficiently precise to capture relationships between per-cell Chl a and cytometer red fluorescence, providing a bridge between biomass estimates from cell counts and bulk measurements of total Chl a.https://www.frontiersin.org/articles/10.3389/fmars.2022.850646/fullphytoplankton community structurechlorophyllflow cytometryfluorescencepicophytoplankton |
| spellingShingle | Nicholas Bock Ajit Subramaniam Andrew R. Juhl Joseph Montoya Solange Duhamel Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell Sorting Frontiers in Marine Science phytoplankton community structure chlorophyll flow cytometry fluorescence picophytoplankton |
| title | Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell Sorting |
| title_full | Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell Sorting |
| title_fullStr | Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell Sorting |
| title_full_unstemmed | Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell Sorting |
| title_short | Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell Sorting |
| title_sort | quantifying per cell chlorophyll a in natural picophytoplankton populations using fluorescence activated cell sorting |
| topic | phytoplankton community structure chlorophyll flow cytometry fluorescence picophytoplankton |
| url | https://www.frontiersin.org/articles/10.3389/fmars.2022.850646/full |
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