Physiological and evolutionary potential of microorganisms from the Canterbury Basin subseafloor, a metagenomic approach

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doi: 10.1093/femsec/fiv029
Author(s): Gaboyer, Frédéric; Burgaud, Gaëtan; Alain, Karine
Author Affiliation(s): Primary:
Centre National de la Recherche Scientifique, Centre de Biophysique Moléculaire, Orleans, France
Other:
Université de Brest, France
Institut Universitaire Européen de la Mer, France
Volume Title: FEMS Microbiology. Ecology
Source: FEMS Microbiology. Ecology, 91(5). Publisher: Blackwell Publishing, Amsterdam, Netherlands. ISSN: 0168-6496
Note: In English. 45 refs.; illus., incl. 2 tables
Summary: Subseafloor sediments represent a large reservoir of organic matter and are inhabited by microbial groups of the three domains of life. Besides impacting the planetary geochemical cycles, the subsurface biosphere remains poorly understood, notably questions related to possible metabolic pathways and selective advantages that may be deployed by buried microorganisms (sporulation, response to stress, dormancy). In order to better understand physiological potentials and possible lifestyles of subseafloor microbial communities, we analyzed two metagenomes from subseafloor sediments collected at 31 mbsf (meters below the sea floor) and 136 mbsf in the Canterbury Basin. Metagenomic phylogenetic and functional diversities were very similar. Phylogenetic diversity was mostly represented by Chloroflexi, Firmicutes and Proteobacteria for Bacteria and by Thaumarchaeota and Euryarchaeota for Archaea. Predicted anaerobic metabolisms encompassed fermentation, methanogenesis and utilization of fatty acids, aromatic and halogenated substrates. Potential processes that may confer selective advantages for subsurface microorganisms included sporulation, detoxication equipment or osmolyte accumulation. Annotation of genomic fragments described the metabolic versatility of Chloroflexi, Miscellaneous Crenarchaeotic Group and Euryarchaeota and showed frequent recombination events within subsurface taxa. This study confirmed that the subseafloor habitat is unique compared to other habitats at the (meta)-genomic level and described physiological potential of still uncultured groups.
Year of Publication: 2015
Research Program: IODP Integrated Ocean Drilling Program
Key Words: 07 Marine Geology and Oceanography; Australasia; Biodiversity; Biologic evolution; Canterbury Basin; Carboxylic acids; Chemical composition; DNA; Ecology; Expedition 317; Fatty acids; Genome; Geochemistry; IODP Site U1352; Integrated Ocean Drilling Program; Marine sediments; Microorganisms; New Zealand; North Island; Nucleic acids; Ocean floors; Organic acids; Organic compounds; Pacific Ocean; Phylogeny; Physiology; Sediments; South Pacific; Southwest Pacific; West Pacific
Coordinates: S445615 S445615 E1720122 E1720122
S445700 S444600 E1720200 E1714000
Record ID: 2018086708
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute.