Dataset Information

Deep Biosphere - Beatrix 326 BH2 (270712)

ABSTRACT: This project aims to investigate the metabolic pathways expressed by the active microbial community occurring at the deep continental subsurface. Subsurface chemoLithoautotrophic Microbial Ecosystems (SLiMEs) under oligotrophic conditions are supported by H2; however, the overall ecological trophic structures of these communities are poorly understood. Some deep, fluid-filled fractures in the Witwatersrand Basin, South Africa appear to support inverted trophic pyramids wherein methanogens contributing <5% of the total DNA apparently produce CH4 that supports the rest of the community. Here we show the active metabolic relationships of one such trophic structure by combining metatranscriptomic assemblies, metaproteomic and stable isotopic data, and thermodynamic modeling. Four autotrophic β-proteobacteria genera that are capable of oxidizing sulfur by denitrification dominate. They co-occur with sulfate reducers, anaerobic methane oxidizers and methanogens, which each comprises <5% of the total community. Defining trophic levels of microbial chemolithoautotrophs by the number of transfers from the initial abiotic H2-driven CO2 fixation, we propose a top-down cascade influence of the metabolic consumers that enhances the fitness of the metabolic producers to explain the inverted biomass pyramid of a multitrophic SLiME. Symbiotic partnerships are pivotal in the deep biosphere on and potentially beyond the Earth.

INSTRUMENT(S): LTQ Orbitrap Elite

ORGANISM(S): Sulfuritalea

SUBMITTER: Maggie Lau

LAB HEAD: Maggie Lau

PROVIDER: PXD004634 | Pride | 2018-10-27

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	BE27_cRNA_5assemblersNew_percolator_mod_2012BH2_data.mgf	Mgf
	BE27_cRNA_5assemblersNew_percolator_mod_2012BH2_data.msf	Msf
	BE27_cRNA_5assemblersNew_percolator_mod_2012BH2_data.pep.xml	Pepxml
	BE27_cRNA_5assemblersNew_percolator_mod_2012BH2_data.prot.xml	Xml
	BE27_cRNA_5assemblersNew_percolator_mod_2012H_data.mgf	Mgf

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Publications

Taxonomic and Functional Compositions Impacted by the Quality of Metatranscriptomic Assemblies.

Lau Maggie C Y MCY Harris Rachel L RL Oh Youmi Y Yi Min Joo MJ Behmard Aida A Onstott Tullis C TC

Frontiers in microbiology 20180620

Metatranscriptomics has recently been applied to investigate the active biogeochemical processes and elemental cycles, and in situ responses of microbiomes to environmental stimuli and stress factors. De novo assembly of RNA-Sequencing (RNA-Seq) data can reveal a more detailed description of the metabolic interactions amongst the active microbial communities. However, the quality of the assemblies and the depiction of the metabolic network provided by various de novo assembl ...[more]

PMID: 29973918

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