Exopolymeric substances control microbial community structure and function by contributing to both C and Fe nutrition in Fe-limited Southern Ocean provinces


Contact
Scarlett.Trimborn [ at ] awi.de

Abstract

Organic ligands such as exopolymeric substances (EPS) are known to form complexes with iron (Fe) and modulate phytoplankton growth. However, the effect of organic ligands on bacterial and viral communities remains largely unknown. Here, we assessed how Fe associated with organic ligands influences phytoplankton, microbial, and viral abundances and their diversity in the Southern Ocean. While the particulate organic carbon (POC) was modulated by Fe chemistry and bioavailability in the Drake Passage, the abundance and diversity of microbes and viruses were not governed by Fe bioavailability. Only following amendments with bacterial EPS did bacterial abundances increase, while phenotypic alpha diversity of bacterial and viral communities decreased. The latter was accompanied by significantly enhanced POC, pointing toward the relief of C limitation or other drivers of the microbial loop. Based on the literature and our findings, we propose a conceptual framework by which EPS may affect phytoplankton, bacteria, and viruses. Given the importance of the Southern Ocean for Earth’s climate as well as the prevalence of viruses and their increasingly recognized impact on marine biogeochemistry and C cycling; the role of microbe–virus interactions on primary productivity in the Southern Ocean needs urgent attention.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Peer revision
ISI/Scopus peer-reviewed
Publication Status
Published
Eprint ID
53552
DOI 10.3390/micro organisms8121980

Cite as
Blanco Ameijeiras, S. , Cababes, D. J. E. , Cable, R. , Trimborn, S. , Jacquet, S. , Wiegmann, S. , Völkner, C. , Lelchat, F. , Bracher, A. , Duhaime, M. and Hassler, C. (2020): Exopolymeric substances control microbial community structure and function by contributing to both C and Fe nutrition in Fe-limited Southern Ocean provinces , Microorganisms, 8 (12), pp. 1-21 . doi: 10.3390/micro organisms8121980


Share


Citation

Research Platforms

Campaigns


Actions
Edit Item Edit Item