Bacterioplankton taxa compete for iron along the early spring-summer transition in the Arctic Ocean

• Main Authors: Puente-Sánchez, Fernando, Macías-Pérez, Luis Alberto, Campbell, Karley L, Royo-Llonch, Marta, Balagué, Vanessa, Sánchez, Pablo, Tamames, Javier, Mundy, Christopher John, Pedrós-Alió, Carlos
• Other Authors: Ministerio de Economía y Competitividad (España), Agencia Estatal de Investigación (España), Natural Sciences and Engineering Research Council of Canada, Swedish Research Council, Consejo Superior de Investigaciones Científicas https://ror.org/02gfc7t72
• Format: Article in Journal/Newspaper
• Language: English
• Published: John Wiley & Sons 2024
• Subjects: Arctic Ocean; Bacteroidetes; Competition; Gammaproteobacteria; Iron; Sea ice
• Online Access: http://hdl.handle.net/10261/364884; https://doi.org/10.1002/ece3.11546; https://doi.org/10.13039/501100000038; https://doi.org/10.13039/501100011033; https://doi.org/10.13039/501100003329; https://api.elsevier.com/content/abstract/scopus_id/85196279507

Microbial assemblages under the sea ice of the Dease Strait, Canadian Arctic, were sequenced for metagenomes of a small size fraction (0.2-3 μm). The community from early March was typical for this season, with Alpha- and Gammaproteobacteria as the dominant taxa, followed by Thaumarchaeota and Bacteroidetes. Toward summer, Bacteroidetes, and particularly the genus Polaribacter, became increasingly dominant, followed by the Gammaproteobacteria. Analysis of genes responsible for microbial acquisition of iron showed an abundance of ABC transporters for divalent cations and ferrous iron. The most abundant transporters, however, were the outer membrane TonB-dependent transporters of iron-siderophore complexes. The abundance of iron acquisition genes suggested this element was essential for the microbial assemblage. Interestingly, Gammaproteobacteria were responsible for most of the siderophore synthesis genes. On the contrary, Bacteroidetes did not synthesize siderophores but accounted for most of the transporters, suggesting a role as cheaters in the competition for siderophores as public goods. This cheating ability of the Bacteroidetes may have contributed to their dominance in the summer. Ministerio de Economía y Competitividad, Grant/Award Number: PID2019- 110011RB-C33; Vetenskapsrådet, Grant/ Award Number: 2022-04801; Natural Sciences and Engineering Research Council of Canada; Discovery and Northern Research Supplement Grant; CEX2019-000928-S, Grant/Award Number: Agencia Estatal de Investigación Peer reviewed