The final, formatted version of the article will be published soon.
ORIGINAL RESEARCH article
Front. Mar. Sci.
Sec. Global Change and the Future Ocean
Volume 11 - 2024 |
doi: 10.3389/fmars.2024.1456799
Seawater Temperature Drives the Diversity of Key Cyanobacteria (Synechococcus and Prochlorococcus) in a Warming Sea
Provisionally accepted- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Makkah, Saudi Arabia
The picocyanobacteria genera Prochlorococcus and Synechococcus play a significant role globally, dominating the primary production in warm and oligotrophic tropical and subtropical areas, which represent the largest oceanic ecosystem. Despite their little morphological variability, gGenomic studies have revealed high microdiversity within these genera. It is anticipated that ocean warming may cause decreased biodiversity in marine tropical areas, as increasing temperatures may lead to the development of a new thermal niche in these regions. Thus, our study aimed to characterize the microdiversity of picocyanobacteria in the Red Sea, one of the warmest oligotrophic seas on the planet, which is experiencing warming at a rate that exceeds the global average. We identified picocyanobacteria microdiversity in the open waters of the Eastern Red Sea basin, where seawater temperatures ranged from 22.2 to 32.4 °C throughout the water column (from surface to 160 m depth). Both Prochlorococcus and Synechococcus populations were characterized to deep taxonomic levels, applying amplicon sequencing targeting the petB gene, revealing up to 15 different (sub)clades. Synechococcus dominated the basin, representing an average of 68.8 % of the total reads assigned to both cyanobacteria. The subclade Synechococcus IIa and Prochlorococcus clade HLII were ubiquitous in the water column of the Eastern Red Sea basin, representing the 73% and 56% of the Synechococcus and Prochlorococcus assigned reads, respectively. Maximum cyanobacteria richness was observed at approximately 27.5 °C, declining at higher and lower temperatures (polynomial fit, R 2 = 0.2, p<0.0001). Synechococcus IIa dominated in the warmest surface waters (>30°C) of the Red Sea, displacing other (sub)clades to more saline and nutrient-poor waters, thereby reducing community diversity (polynomial fit, R 2 = 0.77, p<0.0001). Our study contributes to identifying changes in picocyanobacterial diversity when exposed to temperatures exceeding current oceanic thermal limits, through the analysis of Red Sea communities already inhabiting such highertemperature niches.
Keywords: picocyanobacteria, Prochlorococcus HLII, Synechococcus IIa, microdiversity, warming, Red Sea, temperature
Received: 29 Jun 2024; Accepted: 27 Aug 2024.
Copyright: © 2024 Coello-Camba and Agusti. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence:
Alexandra Coello-Camba, Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, 23955, Makkah, Saudi Arabia
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.