Diverse hydrogen production and consumption pathways influence methane production in ruminants

The ISME Journal, Journal Year: 2019, Volume and Issue: 13(10), P. 2617 - 2632

Published: June 26, 2019

Farmed ruminants are the largest source of anthropogenic methane emissions globally. The methanogenic archaea responsible for these use molecular hydrogen (H2), produced during bacterial and eukaryotic carbohydrate fermentation, as their primary energy source. In this work, we used comparative genomic, metatranscriptomic co-culture-based approaches to gain a system-wide understanding organisms pathways ruminal H2 metabolism. Two-thirds sequenced rumen archaeal genomes encode enzymes that catalyse production or consumption, including 26 distinct hydrogenase subgroups. Metatranscriptomic analysis confirmed hydrogenases differentially expressed in sheep rumen. Electron-bifurcating [FeFe]-hydrogenases from carbohydrate-fermenting Clostridia (e.g., Ruminococcus) accounted half all transcripts. Various uptake were also expressed, methanogenesis (Methanobrevibacter), fumarate nitrite reduction (Selenomonas), acetogenesis (Blautia). Whereas methanogenesis-related transcripts predominated high yield sheep, alternative significantly upregulated low sheep. Complementing findings, observed significant differential expression activity hydrogenogenic cellulose fermenter Ruminococcus albus hydrogenotrophic reducer Wolinella succinogenes co-culture compared with pure culture. We conclude metabolism is more complex widespread trait among microorganisms than previously recognised. There evidence hydrogenotrophs, acetogenic respiratory bacteria, can prosper effectively compete methanogens H2. These findings may help inform ongoing strategies mitigate by increasing flux through pathways, animal selection, dietary supplementation inhibitors.

Language: Английский

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Thermogenic hydrocarbon biodegradation by diverse depth-stratified microbial populations at a Scotian Basin cold seep

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: Nov. 17, 2020

At marine cold seeps, gaseous and liquid hydrocarbons migrate from deep subsurface origins to the sediment-water interface. Cold seep sediments are known host taxonomically diverse microorganisms, but little is about their metabolic potential depth distribution in relation hydrocarbon electron acceptor availability. Here we combined geophysical, geochemical, metagenomic metabolomic measurements profile microbial activities at a newly discovered sea. Metagenomic profiling revealed compositional functional differentiation between near-surface deeper layers. In both sulfate-rich sulfate-depleted depths, various archaeal bacterial community members actively oxidizing thermogenic anaerobically. Depth distributions of hydrocarbon-oxidizing archaea that they not necessarily associated with sulfate reduction, which especially surprising for anaerobic ethane butane oxidizers. Overall, these findings link subseafloor microbiomes biochemical mechanisms degradation deeply-sourced hydrocarbons.

Language: Английский

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Bacterial fermentation and respiration processes are uncoupled in anoxic permeable sediments

Nature Microbiology, Journal Year: 2019, Volume and Issue: 4(6), P. 1014 - 1023

Published: March 11, 2019

Language: Английский

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Geological storage of hydrogen in deep aquifers – an experimental multidisciplinary study

Energy & Environmental Science, Journal Year: 2022, Volume and Issue: 15(8), P. 3400 - 3415

Published: Jan. 1, 2022

This first multidisciplinary study simulating the H 2 arrival in deep aquifers used as geological storage shows importance of microorganisms.

Language: Английский

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Unveiling the inhibitory mechanisms of chromium exposure on microbial reductive dechlorination: Kinetics and microbial responses

Water Research, Journal Year: 2024, Volume and Issue: 253, P. 121328 - 121328

Published: Feb. 16, 2024

Language: Английский

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Molecular Hydrogen, a Neglected Key Driver of Soil Biogeochemical Processes

Applied and Environmental Microbiology, Journal Year: 2019, Volume and Issue: 85(6)

Published: Jan. 17, 2019

The atmosphere of the early Earth is hypothesized to have been rich in reducing gases such as hydrogen (H2). H2 has proposed first electron donor leading ATP synthesis due its ubiquity throughout biosphere well ability easily diffuse through microbial cells and low activation energy requirement. Even today, hydrogenase enzymes enabling production oxidation are found thousands genomes spanning three domains life across aquatic, terrestrial, even host-associated ecosystems. though already a universal growth maintenance source, potential contribution driver biogeochemical cycles received little attention. Here, we bridge this knowledge gap by providing an overview classification, distribution, physiological role hydrogenases. Distribution these various functional groups recent experimental evidence finally integrated support hypothesis that H2-oxidizing microbes keystone species driving C cycling along O2 concentration gradients H2-rich soil In conclusion, suggest focusing on metabolic flexibility combining community-level individual-level approaches aiming decipher impact C-cycling microbes, via both culture-dependent culture-independent methods, give us more insight into processes.

Language: Английский

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Anaerobic Benzene Biodegradation Linked to the Growth of Highly Specific Bacterial Clades

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(12), P. 7970 - 7980

Published: May 27, 2021

Reliance on bioremediation to remove benzene from anoxic environments has proven risky for decades but unknown reasons. Research revealed a strong link between anaerobic biodegradation and the enrichment of highly specific microbes, including Thermincola in family Peptococcaceae deltaproteobacterial Candidate Sva0485 clade. Using aquifer materials Canadian Forces Base Borden, we compared five approaches batch microcosms. Under conditions simulating natural attenuation or sulfate biostimulation, was not degraded after 1–2 years incubation no known benzene-degrading microbes occurred. In contrast, nitrate-amended microcosms reported coincident with significant growth spp., along functional gene presumed catalyze carboxylation (abcA). Inoculation 2.5% methanogenic consortium containing (Deltaproteobacteria ORM2) resulted presence under conditions. The other hydrocarbon co-contaminants decreased rates degradation by factor 2 4. Tracking abundance abcA 16S rRNA genes is recommended monitor groundwater systems further uncover growth-rate-limiting these two intriguing phylotypes.

Language: Английский

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Microbial diversity and processes in groundwater

Elsevier eBooks, Journal Year: 2023, Volume and Issue: unknown, P. 211 - 240

Published: Jan. 1, 2023

Language: Английский

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Identification of intestinal and fecal microbial biomarkers using a porcine social stress model

Frontiers in Microbiology, Journal Year: 2023, Volume and Issue: 14

Published: Nov. 9, 2023

Understanding the relationships between social stress and gastrointestinal microbiota, how they influence host health performance is expected to have many scientific commercial implementations in different species, including identification improvement of challenges animal welfare health. In particular, study impact on microbiota pigs may be interest as a model for human A porcine based repeated regrouping reduced space allowance during last 4 weeks finishing period was developed identify stress-induced changes gut microbiome composition. The application resulted significant increase salivary cortisol concentration over course trial decreased growth appetite. applied 32 bacteria being either enriched (13) or depleted (19) intestine feces. Fecal samples showed greater number microbial genera influenced by than caecum colon samples. Our revealed that opportunistic pathogens Treponema Clostridium were colonic fecal from stressed pigs. Additionally, such Streptococcus, Parabacteroides, Desulfovibrio, Terrisporobacter, Marvinbryantia, Romboutsia found response stress. contrast, Prevotella, Faecalibacterium, Butyricicoccus, Dialister, Alloprevotella, Megasphaera, Mitsuokella depleted. These are great because synthesize metabolites [e.g., short-chain fatty acids (SCFA), butyrate] showing beneficial benefits due inhibitory effects pathogenic species. Of particular Dialister their depletion identified associated with inferior quality life depression. We also some more susceptible indicated large enrichments Clostridium, Treponema, Streptococcus Campylobacter. Generally, our results provide further evidence microbiota-gut-brain axis an regulated hypothalamic-pituitary-adrenal axis, change composition, particularly known pathogenicity mental diseases.

Language: Английский

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Lytic archaeal viruses infect abundant primary producers in Earth’s crust

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: July 30, 2021

Abstract The continental subsurface houses a major portion of life’s abundance and diversity, yet little is known about viruses infecting microbes that reside there. Here, we use combination metagenomics virus-targeted direct-geneFISH (virusFISH) to show highly abundant carbon-fixing organisms the uncultivated genus Candidatus Altiarchaeum are frequent targets previously unrecognized in deep subsurface. Analysis CRISPR spacer matches display resistances Ca . Altiarchaea against eight predicted viral clades, which genomic relatedness across continents but similarity identified viruses. Based on metagenomic information, tag image putatively genome rich protospacers using fluorescence microscopy. VirusFISH reveals lytic lifestyle respective virus challenges previous predictions lysogeny prevails as dominant development over time imaging 18 samples from one ecosystem suggest sophisticated interplay diversification adapting CRISPR-mediated Altiarchaeum. We conclude infections primary producers with followed by cell lysis potentially jump-start heterotrophic carbon cycling these ecosystems.

Language: Английский

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