A Contemporary Microbially Maintained Subglacial Ferrous "Ocean"

  title={A Contemporary Microbially Maintained Subglacial Ferrous "Ocean"},
  author={Jill A. Mikucki and Ann Pearson and David T. Johnston and Alexandra V. Turchyn and J. Farquhar and Daniel P. Schrag and Ariel D. Anbar and John C. Priscu and Peter A. Lee},
  pages={397 - 400}
An active microbial assemblage cycles sulfur in a sulfate-rich, ancient marine brine beneath Taylor Glacier, an outlet glacier of the East Antarctic Ice Sheet, with Fe(III) serving as the terminal electron acceptor. Isotopic measurements of sulfate, water, carbonate, and ferrous iron and functional gene analyses of adenosine 5′-phosphosulfate reductase imply that a microbial consortium facilitates a catalytic sulfur cycle. These metabolic pathways result from a limited organic carbon supply… Expand
An emerging picture of Neoproterozoic ocean chemistry: Insights from the Chuar Group, Grand Canyon, USA
Abstract Detailed iron, sulfur and carbon chemistry through the > 742 million year old Chuar Group reveals a marine basin dominated by anoxic and ferrous iron-rich (ferruginous) bottom watersExpand
Microbial life at −13 °C in the brine of an ice-sealed Antarctic lake
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Metagenomic Insights into Microbial Metabolisms of a Sulfur-Influenced Glacial Ecosystem
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Subglacial Lake Whillans microbial biogeochemistry: a synthesis of current knowledge
  • J. Mikucki, P. Lee, +16 authors M. Tranter
  • Environmental Science, Medicine
  • Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
  • 2016
The analysis of water and sediments from the lake revealed a diverse microbial community composed of bacteria and archaea that are close relatives of species known to use reduced N, S or Fe and CH4 as energy sources, providing unequivocal evidence that subglacial environments in this region of West Antarctica host active microbial ecosystems that participate in sub glacial biogeochemical cycling. Expand
Microbial Fe(III) reduction as a potential iron source from Holocene sediments beneath Larsen Ice Shelf
The authors show that microbial alteration of illite could provide a potential source of Fe release to Southern Ocean waters during Holocene glacial cycles, and identify another ice-sheet feedback intimately tied to iron biogeochemistry during climate transitions. Expand
Microbial Communities in Antarctic Subglacial Aquatic Environments
Glaciological processes under ice masses, including ice sheets, produce conditions favorable for microbes by forming subglacial aquatic environments (SAE) through basal melting and providingExpand
Microbial sulfur transformations in sediments from Subglacial Lake Whillans
The results infer the presence of sulfur oxidation, which can be a significant energetic pathway for chemosynthetic biosynthesis in SLW sediments, which ultimately flows into the Ross Sea. Expand
Microbiology of Subglacial Environments
The abundance of water at the base of glaciers and polar ice sheets forms lacustrine features and habitats in the saturated sediments of subglacial hydrological systems. Nutrients and energy sourcesExpand
Off Limits: Sulfate below the Sulfate-Methane Transition
One of the most intriguing recent discoveries in biogeochemistry is the ubiquity of cryptic sulfur cycling. From subglacial lakes to marine oxygen minimum zones, and in marine sediments, crypticExpand
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Ferruginous Conditions Dominated Later Neoproterozoic Deep-Water Chemistry
It is reported that through much of the later Neoproterozoic, anoxia remained widespread beneath the mixed layer of the oceans; deeper water masses were sometimes sulfidic but were mainly Fe2+-enriched, marking a return to ocean chemistry not seen for more than one billion years of Earth history. Expand
A new model for Proterozoic ocean chemistry
There was a significant oxidation of the Earth's surface around 2 billion years ago (2 Gyr). Direct evidence for this oxidation comes, mostly, from geological records of the redox-sensitive elementsExpand
Geomicrobiology of subglacial ice above Lake Vostok, Antarctica.
Bacterial 16S ribosomal DNA genes revealed low diversity in the gene population, and phylotypes were closely related to extant members of the alpha- and beta-Proteobacteria and the Actinomycetes. Expand
Oxygen isotopic composition of sulfate in deep sea pore fluid: Evidence for rapid sulfur cycling
Changes in the major element and related isotope profiles in porewaters of organic-rich sediments suggest that various microbial processes using a succession of electron acceptors are in play duringExpand
Oxygen Isotope Constraints on the Sulfur Cycle over the Past 10 Million Years
A numerical model suggests that sea level fluctuations during Plio-Pleistocene glacial cycles affected the sulfur cycle by reducing the area of continental shelves and increasing the oxidative weathering of pyrite. Expand
Microbially Driven Redox Reactions in Anoxic Environments: Pathways, Energetics, and Biochemical Consequences
After consumption of molecular oxygen, anaerobic microbial communities can use a continuum of alternative electron acceptors such as nitrate, manganese oxides, iron oxides, sulfate or CO2, withExpand
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Bacterial Diversity Associated with Blood Falls, a Subglacial Outflow from the Taylor Glacier, Antarctica
The results, together with previous reports, suggest that the brine below the Taylor Glacier hosts a viable ecosystem with microorganisms capable of growth, supported by chemical energy present in reduced iron and sulfur compounds. Expand
Pleistocene ice and paleo-strain rates at Taylor Glacier, Antarctica
Abstract Ice exposed in ablation zones of ice sheets can be a valuable source of samples for paleoclimate studies and information about long-term ice dynamics. We report a 28-km long stable isotopeExpand
Mass-Independent Sulfur of Inclusions in Diamond and Sulfur Recycling on Early Earth
Populations of sulfide inclusions in diamonds from the Orapa kimberlite pipe in the Kaapvaal-Zimbabwe craton, Botswana, preserve mass-independent sulfur isotope fractionations. The data indicate thatExpand