| Registro completo |
| Provedor de dados: |
ArchiMer
|
| País: |
France
|
| Título: |
Regulation of the Phytoplankton Heme b Iron Pool During the North Atlantic Spring Bloom
|
| Autores: |
Louropoulou, Evangelia
Gledhill, Martha
Browningi, Thomas J.
Desai, Dhwani K.
Barraqueta, Jan-lukas Menzel
Tonnard, Manon
Sarthou, Geraldine
Planquette, Helene
Bowie, Andrew R.
Schmitz, Ruth A.
Laroche, Julie
Achterberg, Eric P.
|
| Data: |
2019-07
|
| Ano: |
2019
|
| Palavras-chave: |
Heme b
North Atlantic
Phytoplankton
Diatoms
Iron
Limitation
GEOTRACES
GEOVIDE
|
| Resumo: |
Heme b is an iron-containing co-factor in hemoproteins. Heme b concentrations are low (< 1 pmol L-1) in iron limited phytoplankton in cultures and in the field. Here, we determined heme b in marine particulate material (> 0.7 mu m) 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-1 (median = 2.0 pmol L-1, 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-1, n = 12) were observed, whilst the biomass was highest (particulate organic carbon, median = 14.2 mu mol L-1, n = 25; chlorophyll a: median = 2.0 nmol L-1, 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-1, 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-1, 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.
|
| Tipo: |
Text
|
| Idioma: |
Inglês
|
| Identificador: |
https://archimer.ifremer.fr/doc/00508/61940/66029.pdf
https://archimer.ifremer.fr/doc/00508/61940/66030.zip
DOI:10.3389/fmicb.2019.01566
https://archimer.ifremer.fr/doc/00508/61940/
|
| Editor: |
Frontiers Media Sa
|
| Formato: |
application/pdf
|
| Fonte: |
Frontiers In Microbiology (1664-302X) (Frontiers Media Sa), 2019-07 , Vol. 10 , N. 1566 , P. 16p.
|
| Direitos: |
info:eu-repo/semantics/openAccess
restricted use
|
|
