Titre :

Major changes in the composition of a Southern Ocean bacterial community in response to diatom-derived dissolved organic matter

Auteur(s) :

Landa, Marine [Auteur]
Laboratoire d'Océanographie Microbienne [LOMIC]
University of California [Santa Cruz] [UC Santa Cruz]
Blain, Stéphane [Auteur]
Laboratoire d'Océanographie Microbienne [LOMIC]
Harmand, Jérôme [Auteur]
Laboratoire de Biotechnologie de l'Environnement [Narbonne] [LBE]
Monchy, Sébastien [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Rapaport, Alain [Auteur]
Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie [MISTEA]
Obernosterer, Ingrid [Auteur]
Laboratoire d'Océanographie Microbienne [LOMIC]

Titre de la revue :

FEMS Microbiology Ecology

Pagination :

1-46

Éditeur :

Wiley-Blackwell

Date de publication :

2018-03-14

ISSN :

0168-6496

Mot(s)-clé(s) en anglais :

Dissolved organic matter
Southern Ocean
Bacterial community composition
16S rRNA gene sequencing
Continuous cultures

Discipline(s) HAL :

Sciences du Vivant [q-bio]/Biodiversité
Planète et Univers [physics]/Océan, Atmosphère
Mathématiques [math]/Systèmes dynamiques [math.DS]
Informatique [cs]/Modélisation et simulation

Résumé en anglais : [en]

In the Southern Ocean, natural iron fertilization in the wake of islands leads to annually occurring spring phytoplankton blooms associated with enhanced heterotrophic activity through the release of labile dissolved organic ...
Lire la suite >In the Southern Ocean, natural iron fertilization in the wake of islands leads to annually occurring spring phytoplankton blooms associated with enhanced heterotrophic activity through the release of labile dissolved organic matter (DOM). The aim of this study was to investigate experimentally how diatom-derived DOM affects the composition of Southern Ocean winter water bacterial communities and to identify the most responsive taxa. A bacterial community collected in the naturally iron-fertilized region off Kerguelen Island (KEOPS2 October-November 2011) was grown onboard in continuous cultures, on winter water alone or amended with diatom-derived DOM supplied at identical DOC concentrations. 454 sequencing of 16S amplicons revealed that the two DOM sources sustained strikingly different bacterial communities, with higher relative abundances of Sulfitobacter, Colwellia and Methylophaga OTUs and lower relative abundances of Polaribacter, Marinobacter, NAC11–7 and SAR11 OTUs in diatom-DOM compared to winter water conditions. Using a modeling approach, we obtained growth rates for phylogenetically diverse taxa varying between 0.12 and 0.49 d−1 under carbon-limited conditions. Our results identify diatom-DOM as a key factor shaping Southern Ocean winter water bacterial communities and suggest a role for niche partitioning and microbial interactions in organic matter utilization.Lire moins >

Langue :

Anglais

Vulgarisation :

Non

Projet ANR :

Kerguelen : Comparaison plateau Ocean2

Collections :

• Laboratoire d'Océanologie et de Géosciences (LOG) - UMR 8187

Source :

Harvested from HAL