A ubiquitous gammaproteobacterial clade dominates expression of sulfur oxidation genes across the mesopelagic ocean

Author(s)
Federico Baltar, Clara Martínez-Pérez, Chie Amano, Marion Vial, Semidán Robaina-Estévez, Thomas Reinthaler, Gerhard J. Herndl, Zihao Zhao, Ramiro Logares, Sergio E. Morales, José M. González
Abstract

The deep ocean (>200 m depth) is the largest habitat on Earth. Recent evidence suggests sulfur oxidation could be a major energy source for deep ocean microbes. However, the global relevance and the identity of the major players in sulfur oxidation in the oxygenated deep-water column remain elusive. Here we combined single-cell genomics, community metagenomics, metatranscriptomics and single-cell activity measurements on samples collected beneath the Ross Ice Shelf in Antarctica to characterize a ubiquitous mixotrophic bacterial group (UBA868) that dominates expression of RuBisCO genes and of key sulfur oxidation genes. Further analyses of the gene libraries from the ‘Tara Oceans’ and ‘Malaspina’ expeditions confirmed the ubiquitous distribution and global relevance of this enigmatic group in the expression of sulfur oxidation and dissolved inorganic carbon fixation genes across the global mesopelagic ocean. Our study also underscores the unrecognized importance of mixotrophic microbes in the biogeochemical cycles of the deep ocean.

Organisation(s)
Functional and Evolutionary Ecology
External organisation(s)
Spanish National Research Council (CSIC), University of Otago, University of La Laguna
Journal
Nature Microbiology
Volume
8
Pages
1137-1148
No. of pages
12
ISSN
2058-5276
DOI
https://doi.org/10.1038/s41564-023-01374-2
Publication date
2023
Peer reviewed
Yes
Austrian Fields of Science 2012
106021 Marine biology
ASJC Scopus subject areas
Applied Microbiology and Biotechnology, Microbiology (medical), Genetics, Cell Biology, Microbiology, Immunology
Sustainable Development Goals
SDG 14 - Life Below Water
Portal url
https://ucrisportal.univie.ac.at/en/publications/a-ubiquitous-gammaproteobacterial-clade-dominates-expression-of-sulfur-oxidation-genes-across-the-mesopelagic-ocean(f8fecd66-8659-437f-a674-dc495a356836).html