Hubalek, Valerie
- Uppsala University
Abstract
Microorganisms in the terrestrial deep biosphere host up to 20% of the earth's biomass and are suggested to be sustained by the gases hydrogen and carbon dioxide. A metagenome analysis of three deep subsurface water types of contrasting age (from <20 to several thousand years) and depth (171 to 448 m) revealed phylogenetically distinct microbial community subsets that either passed or were retained by a 0.22 mu m filter. Such cells of <0.22 mu m would have been overlooked in previous studies relying on membrane capture. Metagenomes from the three water types were used for reconstruction of 69 distinct microbial genomes, each with >86% coverage. The populations were dominated by Proteobacteria, Candidate divisions, unclassified archaea and unclassified bacteria. The estimated genome sizes of the <0.22 mu m populations were generally smaller than their phylogenetically closest relatives, suggesting that small dimensions along with a reduced genome size may be adaptations to oligotrophy. Shallow 'modern marine' water showed community members with a predominantly heterotrophic lifestyle. In contrast, the deeper, 'old saline' water adhered more closely to the current paradigm of a hydrogen-driven deep biosphere. The data were finally used to create a combined metabolic model of the deep terrestrial biosphere microbial community.
Published in
ISME Journal
2016, volume: 10, number: 5, pages: 1192-1203
Publisher: NATURE PUBLISHING GROUP
SLU Authors
UKÄ Subject classification
Microbiology
More information
A correction relating to this article was published in ISME Journal 10(10):2556
Publication identifier
- DOI: https://doi.org/10.1038/ismej.2015.185
Permanent link to this page (URI)
https://res.slu.se/id/publ/84813