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Thermophilic archaea synthesise cellular membranes composed primarily of isoprenoid glycerol dibiphytanyl glycerol tetraethers (iGDGTs). Cells can adjust the packing of their lipids by increasing cyclopentyl ring production, thereby decreasing membrane permeability and fluidity to maintain cellular function at high temperature, acidic pH, or nutrient limitation. Archaea of the class Nitrososphaeria synthesise crenarchaeol, an...
Acquisition and cycling of carbon and nitrogen among members of hot spring communities are not well understood. Metagenomic analyses of 105 communities inhabiting high temperature hot springs across Yellowstone and Iceland showed a co‐distribution pattern of putatively autotrophic and/or diazotrophic (nitrogen‐fixing) Aquificales and Thermus populations. Targeted enrichment of autotrophic and diazotrophic populations in an Ice...
Elemental sulfur (S 8 0 )‐oxidising Sulfolobales (Archaea) dominate high‐temperature acidic hot springs (>80°C, pH 8 0 ‐oxidising members of the Sulfolobales reveal a patchy distribution of genes encoding sulfur oxygenase reductase (SOR), an S 8 0 disproportionating enzyme attributed to S 8 0 oxidation. Here, we report the S 8 0 ‐dependent growth of two Sulfolobales strains previously isolated from acidic hot springs in Yellow...
Hydrothermal systems form at divergent and convergent boundaries of lithospheric plates and within plates due to weakened crust and mantle plumes, playing host to diverse microbial ecosystems. Little is known of how differences in tectonic setting influence the geochemical and microbial compositions of these hydrothermal ecosystems. Here, coordinated geochemical and microbial community analyses were conducted on 87 high‐temper...
Distribution and abundance of tetraether lipid cyclization genes in terrestrial hot springs reflect pHNARA Subscribed
Many Archaea produce membrane‐spanning lipids that enable life in extreme environments. These isoprenoid glycerol dibiphytanyl glycerol tetraethers (GDGTs) may contain up to eight cyclopentyl and one cyclohexyl ring, where higher degrees of cyclization are associated with more acidic, hotter or energy‐limited conditions. Recently, the genes encoding GDGT ring synthases, grsAB , were identified in two Sulfolobaceae; however, th...
Relationships between fluid mixing, biodiversity, and chemosynthetic primary productivity in Yellowstone hot springsNARA Subscribed
The factors that influence biodiversity and productivity of hydrothermal ecosystems are not well understood. Here we investigate the relationship between fluid mixing, biodiversity, and chemosynthetic primary productivity in three co‐localized hot springs (RSW, RSN, and RSE) in Yellowstone National Park that have different geochemistry. All three springs are sourced by reduced hydrothermal fluid, but RSE and RSN receive input...
Storytelling has been the primary means of knowledge transfer over human history. The effectiveness and reach of stories are improved when the message is appropriate for the target audience. Oftentimes, the stories that are most well received and recounted are those that have a clear purpose and that are told from a variety of perspectives that touch on the varied interests of the target audience. Whether scientists realize or...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Seasonal hydrologic and geologic forcing drive hot spring geochemistry and microbial biodiversityNARA Subscribed
Summary Hot springs integrate hydrologic and geologic processes that vary over short‐ and long‐term time scales. However, the influence of temporal hydrologic and geologic change on hot spring biodiversity is unknown. Here, we coordinated near‐weekly, cross‐seasonal (~140 days) geochemical and microbial community analyses of three widely studied hot springs with local precipitation data in Yellowstone National Park. One spring...
Geologic legacy spanning >90 years explains unique Yellowstone hot spring geochemistry and biodiversityNARA Subscribed
Summary Little is known about how the geological history of an environment shapes its physical and chemical properties and how these, in turn, influence the assembly of communities. Evening primrose (EP), a moderately acidic hot spring (pH 5.6, 77.4°C) in Yellowstone National Park (YNP), has undergone dramatic physicochemical change linked to seismic activity. Here, we show that this legacy of geologic change led to the develo...
Probing the geological source and biological fate of hydrogen in Yellowstone hot springsNARA Subscribed
Summary Hydrogen (H 2 ) is enriched in hot springs and can support microbial primary production. Using a series of geochemical proxies, a model to describe variable H 2 concentrations in Yellowstone National Park (YNP) hot springs is presented. Interaction between water and crustal iron minerals yields H 2 that partition into the vapour phase during decompressional boiling of ascending hydrothermal fluids. Variable vapour inpu...
Electron acceptor availability alters carbon and energy metabolism in a thermoacidophileNARA Subscribed
Summary The thermoacidophilic Acidianus strain DS80 displays versatility in its energy metabolism and can grow autotrophically and heterotrophically with elemental sulfur (S°), ferric iron (Fe 3+ ) or oxygen (O 2 ) as electron acceptors. Here, we show that autotrophic and heterotrophic growth with S° as the electron acceptor is obligately dependent on hydrogen (H 2 ) as electron donor; organic substrates such as acetate can on...
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