Disentangling the mechanisms shaping the surface ocean microbiota

Author(s):Show less -

Logares, Ramiro ^{[1, 2]} ; Deutschmann, Ina M. ^[1] ; Junger, Pedro C. ^[3] ; Giner, Caterina R. ^{[1, 4]} ; Krabberod, Anders K. ^[2] ; Schmidt, Thomas S. B. ^[5] ; Rubinat-Ripoll, Laura ^[6] ; Mestre, Mireia ^{[1, 7, 8]} ; Salazar, Guillem ^{[1, 9, 10]} ; Ruiz-Gonzalez, Clara ^[1] ; Sebastian, Marta ^{[1, 11]} ; de Vargas, Colomban ^[6] ; Acinas, Silvia G. ^[1] ; Duarte, Carlos M. ^[12] ; Gasol, Josep M. ^{[1, 13]} ; Massana, Ramon ^[1]

Affiliation:Show less -

^[1] CSIC, Inst Marine Sci ICM, Barcelona 08003 - Spain

^[2] Univ Oslo, Dept Biosci, Sect Genet & Evolutionary Biol, N-0316 Oslo - Norway

^[3] Univ Fed Sao Carlos UFSCar, Dept Hydrobiol DHB, LMPB, BR-13565905 Sao Carlos, SP - Brazil

^[4] Univ British Columbia, Inst Oceans & Fisheries, 2202 Main Mall, Vancouver, BC V6T 1Z4 - Canada

^[5] European Mol Biol Lab, Meyerhofstr 1, D-69117 Heidelberg - Germany

^[6] UPMC Univ Paris 06, Sorbonne Univ, CNRS, UMR 7144, Adaptat & Diversite Milieu Marin Equipe EPEP, Stn, F-29680 Roscoff - France

^[7] Univ Concepcion, Ctr Invest Oceanog COPAS Austral, Dept Oceanog, Concepcion - Chile

^[8] Univ Austral Chile, Ctr FONDAP Invest Dinam Ecosistemas Marinos Altas, Valdivia - Chile

^[9] Swiss Fed Inst Technol, Inst Microbiol, Dept Biol, CH-8093 Zurich - Switzerland

^[10] Swiss Fed Inst Technol, Swiss Inst Bioinformat, CH-8093 Zurich - Switzerland

^[11] Univ Las Palmas Gran Canaria, Oceanog & Global Change Inst, IOCAG, ULPGC, Gran Canaria 35214 - Spain

^[12] KAUST, RSRC, Thuwal - Saudi Arabia

^[13] Edith Cowan Univ, Ctr Marine Ecosyst Res, Sch Sci, Joondalup, WA - Australia

• Document type: Journal article
• Source: MICROBIOME; v. 8, n. 1 APR 20 2020.
• Web of Science Citations: 1

Abstract

Background The ocean microbiota modulates global biogeochemical cycles and changes in its configuration may have large-scale consequences. Yet, the underlying ecological mechanisms structuring it are unclear. Here, we investigate how fundamental ecological mechanisms (selection, dispersal and ecological drift) shape the smallest members of the tropical and subtropical surface-ocean microbiota: prokaryotes and minute eukaryotes (picoeukaryotes). Furthermore, we investigate the agents exerting abiotic selection on this assemblage as well as the spatial patterns emerging from the action of ecological mechanisms. To explore this, we analysed the composition of surface-ocean prokaryotic and picoeukaryotic communities using DNA-sequence data (16S- and 18S-rRNA genes) collected during the circumglobal expeditions Malaspina-2010 and TARA-Oceans. Results We found that the two main components of the tropical and subtropical surface-ocean microbiota, prokaryotes and picoeukaryotes, appear to be structured by different ecological mechanisms. Picoeukaryotic communities were predominantly structured by dispersal-limitation, while prokaryotic counterparts appeared to be shaped by the combined action of dispersal-limitation, selection and drift. Temperature-driven selection appeared as a major factor, out of a few selected factors, influencing species co-occurrence networks in prokaryotes but not in picoeukaryotes, indicating that association patterns may contribute to understand ocean microbiota structure and response to selection. Other measured abiotic variables seemed to have limited selective effects on community structure in the tropical and subtropical ocean. Picoeukaryotes displayed a higher spatial differentiation between communities and a higher distance decay when compared to prokaryotes, consistent with a scenario of higher dispersal limitation in the former after considering environmental heterogeneity. Lastly, random dynamics or drift seemed to have a more important role in structuring prokaryotic communities than picoeukaryotic counterparts. Conclusions The differential action of ecological mechanisms seems to cause contrasting biogeography, in the tropical and subtropical ocean, among the smallest surface plankton, prokaryotes and picoeukaryotes. This suggests that the idiosyncrasy of the main constituents of the ocean microbiota should be considered in order to understand its current and future configuration, which is especially relevant in a context of global change, where the reaction of surface ocean plankton to temperature increase is still unclear. (AU)

• FAPESP's process: 17/26786-1 - Structuring processes of microbial communities and ecological networks in latitudinal gradients of the global ocean
• Grantee: Pedro Ciarlini Junger Soares
• Support Opportunities: Scholarships in Brazil - Doctorate