Regulation of the phytoplankton heme b iron pool during the North Atlantic spring bloom
dc.contributor.author | Louropoulou, Evangelia | en_ZA |
dc.contributor.author | Gledhill, Martha | en_ZA |
dc.contributor.author | Browning, Thomas J. | en_ZA |
dc.contributor.author | Desai, Dhwani K. | en_ZA |
dc.contributor.author | Barraqueta, Jan-Lukas Menzel | en_ZA |
dc.contributor.author | Tonnard, Manon | en_ZA |
dc.contributor.author | Sarthou, Geraldine | en_ZA |
dc.contributor.author | Planquette, Helene | en_ZA |
dc.contributor.author | Bowie, Andrew R. | en_ZA |
dc.contributor.author | Schmitz, Ruth A. | en_ZA |
dc.contributor.author | LaRoche, Julie | en_ZA |
dc.contributor.author | Achterberg, Eric P. | en_ZA |
dc.date.accessioned | 2021-11-03T12:10:55Z | |
dc.date.available | 2021-11-03T12:10:55Z | |
dc.date.issued | 2019-07-11 | |
dc.description | CITATION: Louropoulou, E., et al. 2019. Regulation of the phytoplankton heme b iron pool during the North Atlantic spring bloom. Frontiers in Microbiology, 10:1566, doi:10.3389/fmicb.2019.01566. | |
dc.description | The original publication is available at https://www.frontiersin.org | |
dc.description.abstract | Heme b is an iron-containing co-factor in hemoproteins. Heme b concentrations are low (<1 pmol L⁻²) in iron limited phytoplankton in cultures and in the field. Here, we determined heme b in marine particulate material (>0.7 μm) from the North Atlantic Ocean (GEOVIDE cruise – GEOTRACES section GA01), which spanned several biogeochemical regimes. We examined the relationship between heme b abundance and the microbial community composition, and its utility for mapping iron limited phytoplankton. Heme b concentrations ranged from 0.16 to 5.1 pmol L⁻² (median = 2.0 pmol L⁻², n = 62) in the surface mixed layer (SML) along the cruise track, driven mainly by variability in biomass. However, in the Irminger Basin, the lowest heme b levels (SML: median = 0.53 pmol L⁻², n = 12) were observed, whilst the biomass was highest (particulate organic carbon, median = 14.2 μmol L⁻², n = 25; chlorophyll a: median = 2.0 nmol L⁻², n = 23) pointing to regulatory mechanisms of the heme b pool for growth conservation. Dissolved iron (DFe) was not depleted (SML: median = 0.38 nmol L⁻², n = 11) in the Irminger Basin, but large diatoms (Rhizosolenia sp.) dominated. Hence, heme b depletion and regulation is likely to occur during bloom progression when phytoplankton class-dependent absolute iron requirements exceed the available ambient concentration of DFe. Furthermore, high heme b concentrations found in the Iceland Basin and Labrador Sea (median = 3.4 pmol L⁻², n = 20), despite having similar DFe concentrations to the Irminger Basin, were attributed to an earlier growth phase of the extant phytoplankton populations. Thus, heme b provides a snapshot of the cellular activity in situ and could both be used as indicator of iron limitation and contribute to understanding phytoplankton adaptation mechanisms to changing iron supplies. | en_ZA |
dc.description.uri | https://www.frontiersin.org/articles/10.3389/fmicb.2019.01566/full | |
dc.description.version | Publisher's version | |
dc.format.extent | 16 pages : illustrations | en_ZA |
dc.identifier.citation | Louropoulou, E., et al. 2019. Regulation of the phytoplankton heme b iron pool during the North Atlantic spring bloom. Frontiers in Microbiology, 10:1566, doi:10.3389/fmicb.2019.01566 | |
dc.identifier.issn | 1664-302X (online) | |
dc.identifier.other | doi:10.3389/fmicb.2019.01566 | |
dc.identifier.uri | http://hdl.handle.net/10019.1/123348 | |
dc.language.iso | en_ZA | en_ZA |
dc.publisher | Frontiers Media | |
dc.rights.holder | Authors retain copyright | |
dc.subject | Heme b | en_ZA |
dc.subject | Hemoproteins | en_ZA |
dc.subject | Phytoplankton populations | en_ZA |
dc.subject | Iron -- Analysis | en_ZA |
dc.subject | Diatoms -- North Atlantic | en_ZA |
dc.title | Regulation of the phytoplankton heme b iron pool during the North Atlantic spring bloom | en_ZA |
dc.type | Article | en_ZA |