Change search
Refine search result
1 - 35 of 35
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Bengtson, Stefan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Astolfo, Alberto
    Paul Scherrer Institute.
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Broman, Curt
    Stockholm University.
    Marone, Federica
    Paul Scherrer Institute.
    Stampanoni, Marco
    ETH Zürich.
    Deep-biosphere consortium of fungi and prokaryotes in Eocene sub-seafloor basalts.2014In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 12, no 6, p. 489-496Article in journal (Refereed)
    Abstract [en]

    The deep biosphere of the subseafloor crust is believed to contain a significant part of Earth’s biomass, but because of the difficulties of directly observing the living organisms, its composition and ecology are poorly known. We report here a consortium of fossilized prokaryotic and eukaryotic microorganisms, occupying cavities in deep-drilled vesicular basalt from the Emperor Seamounts, Pacific Ocean, 67.5 meters below seafloor (mbsf). Fungal hyphae provide the framework on which prokaryote-like organisms are suspended like cobwebs and iron-oxidizing bacteria form microstromatolites (Frutexites). The spatial interrelationships show that the organisms were living at the same time in an integrated fashion, suggesting symbiotic interdependence. The community is contemporaneous with secondary mineralizations of calcite partly filling the cavities. The fungal hyphae frequently extend into the calcite, indicating that they were able to bore into the substrate through mineral dissolution. A symbiotic relationship with chemoautotrophs, as inferred for the observed consortium, may be a prerequisite for the eukaryotic colonization of crustal rocks. Fossils thus open a window to the extant as well as the ancient deep biosphere.

  • 2.
    Bengtson, Stefan
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Rasmussen, Birger
    Curtin University.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Muhling, Janet
    Curtin University.
    Broman, Curt
    Stockholm University.
    Marone, Federica
    Stampanoni, Marco
    Bekker, Andrey
    University of California Riverside.
    Fungus-like mycelial fossils in 2.4-billion-year-old vesicular basalt.2017In: Nature Ecology & Evolution, ISSN 2397-334X, Vol. 1, no 6, p. 1-6, article id 0141Article in journal (Refereed)
    Abstract [en]

    Fungi have recently been found to comprise a significant part of the deep biosphere in oceanic sediments and crustal rocks. Fossils occupying fractures and pores in Phanerozoic volcanics indicate that this habitat is at least 400 million years old, but its origin may be considerably older. A 2.4-billion-year-old basalt from the Palaeoproterozoic Ongeluk Formation in South Africa contains filamentous fossils in vesicles and fractures. The filaments form mycelium-like structures growing from a basal film attached to the internal rock surfaces. Filaments branch and anastomose, touch and entangle each other. They are indistinguishable from mycelial fossils found in similar deep-biosphere habitats in the Phanerozoic, where they are attributed to fungi on the basis of chemical and morphological similarities to living fungi. The Ongeluk fossils, however, are two to three times older than current age estimates of the fungal clade. Unless they represent an unknown branch of fungus-like organisms, the fossils imply that the fungal clade is considerably older than previously thought, and that fungal origin and early evolution may lie in the oceanic deep biosphere rather than on land. The Ongeluk discovery suggests that life has inhabited submarine volcanics for more than 2.4 billion years.

  • 3. Chi Fru, E.
    et al.
    Ivarsson, M.
    Swedish Museum of Natural History, Department of Geology.
    Kilias, S. P.
    Frings, Patrick J
    Swedish Museum of Natural History, Department of Geology.
    Hemmingsson, C.
    Broman, C.
    Bengtson, S.
    Swedish Museum of Natural History, Department of Paleobiology.
    Chatzitheodoridis, E.
    Biogenicity of an Early Quaternary iron formation, Milos Island, Greece2015In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 13, no 3, p. 225-244Article in journal (Refereed)
    Abstract [en]

    A ~2.0-million-year-old shallow-submarine sedimentary deposit on Milos Island, Greece, harbours an unmetamorphosed fossiliferous iron formation (IF) comparable to Precambrian banded iron formations (BIFs). This Milos IF holds the potential to provide clues to the origin of Precambrian BIFs, relative to biotic and abiotic processes. Here, we combine field stratigraphic observations, stable isotopes of C, S and Si, rock petrography and microfossil evidence from a ~5-m-thick outcrop to track potential biogeochemical processes that may have contributed to the formation of the BIF-type rocks and the abrupt transition to an overlying conglomerate-hosted IF (CIF). Bulk δ13C isotopic compositions lower than -25‰ provide evidence for biological contribution by the Calvin and reductive acetyl–CoA carbon fixation cycles to the origin of both the BIF-type and CIF strata. Low S levels of ~0.04 wt.% combined with δ34S estimates of up to ~18‰ point to a non-sulphidic depository. Positive δ30Si records of up to +0.53‰ in the finely laminated BIF-type rocks indicate chemical deposition on the seafloor during weak periods of arc magmatism. Negative δ30Si data are consistent with geological observations suggesting a sudden change to intense arc volcanism potentially terminated the deposition of the BIF-type layer. The typical Precambrian rhythmic rocks of alternating Fe- and Si-rich bands are associated with abundant and spatially distinct microbial fossil assemblages. Together with previously proposed anoxygenic photoferrotrophic iron cycling and low sedimentary N and C potentially connected to diagenetic denitrification, the Milos IF is a biogenic submarine volcano-sedimentary IF showing depositional conditions analogous to Archaean Algoma-type BIFs.

  • 4. Chi Fru, Ernest
    et al.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Kilias, Stephanos
    Christoffer, Hemmingson
    Broman, Curt
    Bengtson, Stefan
    C, Chatzitheodoridis
    Biogenicity of an early Quaternary iron formation, Milos Island, Greece2015In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 13, p. 225-244Article in journal (Refereed)
  • 5. Chi Fru, Ernest
    et al.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Kilias, Stephanos P
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Marone, Federica
    Paul Scherrer Institute.
    Fortin, Danielle
    Broman, Curt
    Stampanoni, Marco
    ETH Zürich.
    Fossilized iron bacteria reveal pathway to biological origin of banded iron formation.2013In: Nature Communications, ISSN 2041-1723, Vol. 4, no 2050, p. 1-7Article in journal (Refereed)
    Abstract [en]

    Debates on the formation of banded iron formations in ancient ferruginous oceans are dominated by a dichotomy between abiotic and biotic iron cycling. This is fuelled by difficulties in unravelling the exact processes involved in their formation. Here we provide fossil environmental evidence for anoxygenic photoferrotrophic deposition of analogue banded iron rocks in shallow marine waters associated with an Early Quaternary hydrothermal vent field on Milos Island, Greece. Trace metal, major and rare earth elemental compositions suggest that the deposited rocks closely resemble banded iron formations of Precambrian origin. Well-preserved microbial fossils in combination with chemical data imply that band formation was linked to periodic massive encrustation of anoxygenic phototrophic biofilms by iron oxyhydroxide alternating with abiotic silica precipitation. The data implicate cyclic anoxygenic photoferrotrophy and their fossilization mechanisms in the construction of microskeletal fabrics that result in the formation of characteristic banded iron formation bands of varying silica and iron oxide ratios.

  • 6.
    Chi Fru, Ernest
    et al.
    Department of Geological Sciences, 10691, Stockholm University, Stockholm, Sweden; School of Earth and Ocean Sciences, Cardiff University, Park Place, CF10 3AT Cardiff, UK.
    Kilias, Stephanos
    Department of Economic Geology and Geochemistry, Faculty of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimiopolis, Zographou, 15784, Athens, Greece.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Rattray, Jayne E.
    Department of Geological Sciences, 10691, Stockholm University, Stockholm, Sweden.
    Gkika, Katerina
    Department of Economic Geology and Geochemistry, Faculty of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimiopolis, Zographou, 15784, Athens, Greece.
    McDonald, Iain
    School of Earth and Ocean Sciences, Cardiff University, Park Place, CF10 3AT Cardiff, UK.
    He, Qian
    School of Chemistry, Cardiff University, Park Place, CF10 3AT Cardiff, UK.
    Broman, Curt
    Department of Geological Sciences, 10691, Stockholm University, Stockholm, Sweden.
    Sedimentary mechanisms of a modern banded iron formation on MIlos Island, Greece2018In: Solid Earth, ISSN 1869-9510, E-ISSN 1869-9529, Vol. 9, p. 573-598Article in journal (Refereed)
    Abstract [en]

    An early Quaternary shallow submarine hydrothermal iron formation (IF) in the Cape Vani sedimentary basin (CVSB) on Milos Island, Greece, displays banded rhythmicity similar to Precambrian banded iron formation (BIF). Field-wide stratigraphic and biogeochemical reconstructions show two temporal and spatially isolated iron deposits in the CVSB with distinct sedimentological character. Petrographic screening suggests the presence of a photoferrotrophic-like microfossil-rich IF (MFIF), accumulated on a basement consisting of andesites in a ∼ 150m wide basin in the SW margin of the basin. A banded nonfossiliferous IF (NFIF) sits on top of the Mn-rich sandstones at the transition to the renowned Mn-rich formation, capping the NFIF unit. Geochemical data relate the origin of the NFIF to periodic submarine volcanism and water column oxidation of released Fe(II) in conditions predominated by anoxia, similar to the MFIF. Raman spectroscopy pairs hematite-rich grains in the NFIF with relics of a carbonaceous material carrying an average δ13Corg signature of ∼ −25‰. A similar δ13Corg signature in the MFIF could not be directly coupled to hematite by mineralogy. The NFIF, which postdates large-scale Mn deposition in the CVSB, is composed primarily of amorphous Si (opal-SiO2 ⋅ nH2O) while crystalline quartz (SiO2) predominates the MFIF. An intricate interaction between tectonic processes, changing redox, biological activity, and abiotic Si precipitation are proposed to have collectively formed the unmetamorphosed BIF-type deposits in a shallow submarine volcanic center. Despite the differences in Precambrian ocean–atmosphere chemistry and the present geologic time, these formation mechanisms coincide with those believed to have formed Algoma-type BIFs proximal to active seafloor volcanic centers.

  • 7.
    Drake, Henrik
    et al.
    Linnæus University, Department of Biology and Environmental Science, 39182 Kalmar, Sweden.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology. University of Southern Denmark, Department of Biology and Nordic Center for Earth Evolution, Campusvej 55, Odense M, DK-5230, Denmark.
    The role of anaerobic fungi in fundamental biogeochemical cycles in the deep biosphere2018In: Fungal Biology Reviews, ISSN 1749-4613, E-ISSN 1878-0253, Vol. 32, p. 20-25Article in journal (Refereed)
    Abstract [en]

    A major part of the biologic activity on Earth is hidden underneath our feet in an environment coined the deep biosphere which stretches several kilometers down into the bedrock. The knowledge about life in this vast energy-poor deep system is, however, extremely scarce, particularly for micro-eukaryotes such as fungi, as most studies have focused on prokaryotes. Recent findings suggest that anaerobic fungi indeed thrive at great depth in fractures and cavities of igneous rocks in both the oceanic and the continental crust. Here we discuss the potential importance of fungi in the deep biosphere, in particular their involvement in fundamental biogeochemical processes such as symbiotic relationships with prokaryotes that may have significant importance for the overall energy cycling within this vast subsurface realm. Due to severe oligotrophy, the prokaryotic metabolism at great depth in the crust is very slow and dominantly autotrophic and thus dependent on e.g. hydrogen gas, but the abiotic production of this gas is thought to be insufficient to fuel the deep autotrophic biosphere. Anaerobic fungi are heterotrophs that produce hydrogen gas in their metabolism and have therefore been put forward as a hypothetical provider of this substrate to the prokaryotes. Recent in situ findings of fungi and isotopic signatures within co-genetic sulfide minerals formed from bacterial sulfate reduction in the deep continental biosphere indeed seem to confirm the fungi-prokaryote hypothesis. This suggests that fungi play a fundamental biogeochemical role in the deep biosphere.

  • 8. Drake, Henrik
    et al.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Heim, Christine
    Siljeström, Sandra
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Broman, Curt
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Åström, Mats E.
    Anaerobic consortia of fungi and sulfate reducing bacteria in deep granite fractures2017In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 8, no 55, p. 1-9Article in journal (Refereed)
    Abstract [en]

    The deep biosphere is one of the least understood ecosystems on Earth. Although most microbiological studies in this system have focused on prokaryotes and neglected microeukaryotes, recent discoveries have revealed existence of fossil and active fungi in marine sediments and sub-seafloor basalts, with proposed importance for the subsurface energy cycle. However, studies of fungi in deep continental crystalline rocks are surprisingly few. Consequently, the characteristics and processes of fungi and fungus-prokaryote interactions in this vast environment remain enigmatic. Here we report the first findings of partly organically preserved and partly mineralized fungi at great depth in fractured crystalline rock (-740 m). Based on environmental parameters and mineralogy the fungi are interpreted as anaerobic. Synchrotron-based techniques and stable isotope microanalysis confirm a coupling between the fungi and sulfate reducing bacteria. The cryptoendolithic fungi have significantly weathered neighboring zeolite crystals and thus have implications for storage of toxic wastes using zeolite barriers.

  • 9.
    Drake, Henrik
    et al.
    Linnæus University, Department of Biology and Environmental Science, 39182 Kalmar, Sweden.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology. University of Southern Denmark, Department of Biology and Nordic Center for Earth Evolution, Campusvej 55, Odense M, DK-5230, Denmark.
    Tillberg, Mikael
    Department of Biology and Environmental Science, Linnaeus University, 392 31 Kalmar, Sweden.
    Whitehouse, Martin
    Swedish Museum of Natural History, Department of Geology.
    Kooijman, Ellen
    Swedish Museum of Natural History, Department of Geology.
    Ancient microbial activity in deep hydraulically conductive fracture zones within the Forsmark target area for deep geological nuclear waste disposal, Sweden2018In: Geosciences, Vol. 8, article id 211Article in journal (Refereed)
    Abstract [en]

    Recent studies reveal that organisms from all three domains of life—Archaea, Bacteria, and even Eukarya—can thrive under energy-poor, dark, and anoxic conditions at large depths in the fractured crystalline continental crust. There is a need for an increased understanding of the processes and lifeforms in this vast realm, for example, regarding the spatiotemporal extent and variability of the different processes in the crust. Here, we present a study that set out to detect signs of ancient microbial life in the Forsmark area—the target area for deep geological nuclear waste disposal in Sweden. Stable isotope compositions were determined with high spatial resolution analyses within mineral coatings, and mineralized remains of putative microorganisms were studied in several deep water-conducting fracture zones (down to 663 m depth), from which hydrochemical and gas data exist. Large isotopic variabilities of 13Ccalcite (􀀀36.2 to +20.2‰V-PDB) and 34Spyrite (􀀀11.7 to +37.8‰V-CDT) disclose discrete periods of methanogenesis, and potentially, anaerobic oxidation of methane and related microbial sulfate reduction at several depth intervals. Dominant calcite–water disequilibrium of 18O and 87Sr/86Sr precludes abundant recent precipitation. Instead, the mineral coatings largely reflect an ancient archive of episodic microbial processes in the fracture system, which, according to our microscale Rb–Sr dating of co-genetic adularia and calcite, date back to the mid-Paleozoic. Potential Quaternary precipitation exists mainly at ~400 m depth in one of the boreholes, where mineral–water compositions corresponded.

  • 10. Drake, Henrik
    et al.
    Åström, M.E.
    Heim, Christine
    Broman, Curt
    Åström, J
    Whitehouse, Martin
    Ivarsson, Magnus
    Siljeström, Sandra
    Sjövall, Peter
    Extreme 13C-depletion of carbonates formed during oxidation of biogenic methane in fractured granite2015In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 6Article in journal (Refereed)
  • 11.
    Ivarsson, Lena Norbäck
    et al.
    Stockholm University.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Lundberg, Johannes
    Swedish Museum of Natural History, Department of Botany.
    Sallstedt, Therese
    Swedish Museum of Natural History, Department of Paleobiology.
    Rydin, Catarina
    Stockholm University.
    Epilithic and aerophilic diatoms in the artificial environment of Kungsträdgården metro station, Stockholm, Sweden2013In: International Journal of Speleology, ISSN 0392-6672, E-ISSN 1827-806X, Vol. 42, no 3, p. 289-297Article in journal (Refereed)
    Abstract [en]

    The Kungsträdgården metro station is an artificial and urban subsurface environment illuminated with artificial light. Its ecosystem is almost completely unknown and as a first step to better understand the biology and rock wall habitats the diatom flora was investigated. A total of 12 species were found growing on the rock walls of Kungsträdgården metro station. The results show the diatom flora in Kungsträdgården to be dominated by e.g. Diadesmis contentaDiadesmis perpusillaPinnularia appendiculataNitzschia amphibiaNitzschia sinuata and Diploneis ovalis. One species, Caloneis cf. aerophila, has never been reported from Sweden before. Significant differences in the species composition between the sampling sites indicate Kungsträdgården metro station to be a heterogeneous habitat that provides different microhabitats.

  • 12.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Oceanbottnarnas hemliga liv.2017In: Havsutsikt, ISSN 1104-0513, Vol. 2017, no 2, p. 16-18Article in journal (Other (popular science, discussion, etc.))
    Abstract [sv]

    Berggrunden under havens bottensediment är en vidsträckt men svårtillgänglig och outforskad del av vår planet, särskilt när det gäller liv. Paradoxalt nog är det, förutom haven, världens volymmässigt största livsmiljö för mikroorganismer. Med nya metoder har forskare från Naturhistoriska riksmuseet vänt upp och ner på den gängse vetenskapliga uppfattningen. I den spruckna berggrunden under havssedimenten bor inte bara de förväntade extremt tåliga bakterierna och arkéerna – de har även gott sällskap av svampar.

  • 13.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Stampanoni, Marco
    ETH Zürich.
    Marone, Federica
    Paul Scherrer Institute.
    Tehler, Anders
    Swedish Museum of Natural History, Department of Botany.
    Fossilized fungi in subseafloor Eocene basalts.2012In: Geology, ISSN 0091-7613, Vol. 40, no 2, p. 163-166Article in journal (Refereed)
    Abstract [en]

    The deep biosphere of subseafl oor basalts is thought to consist of mainly prokaryotes (bacteria and archaea). Here we report fossilized fi lamentous microorganisms from subseafl oor basalts interpreted as fossilized fungal hyphae, probably Dikarya, rather than fossilized prokaryotes. The basalts were collected during the Ocean Drilling Program Leg 197 at the Emperor Seamounts, North Pacifi c Ocean, and the fossilized fungi are observed in carbonate-fi lled veins and vesicles in samples that represent a depth of ~150 m below the seafl oor. Three-dimensional visualizations using synchrotron-radiation X-ray tomographic microscopy show characteristic fungal morphology of the mycelium-like network, such as frequent branching, anastomosis, and septa. Possible presence of chitin in the hypha walls was detected by staining with Wheat Germ Agglutinin conjugated with Fluorescein Isothiocyanate and examination using fl uorescence microscopy. The presence of fungi in subseafl oor basalts challenges the present understanding of the deep subseafl oor biosphere as being exclusively prokaryotic.

  • 14.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Carlsson, Diana
    Swedish Museum of Natural History, Department of Paleobiology.
    Är magmatiska bergarterfossilförande?2017In: Geologiskt Forum, ISSN ISSN 1104-4721, no 94, p. 20-23Article, review/survey (Other (popular science, discussion, etc.))
    Abstract [sv]

    Förekomsten av fossil är lika starkt sammankopplad till sedimentära bergarter som magmatiska bergarter är till frånvaron av fossil. Detta har varit ett obestridbart faktum sedan geovetenskapernas gryning. Men nu börjar detta synsätt att ändra sig. Forskare vid Naturhistoriska riksmuseet utforskar ett fossilt arkiv som påträffas i sprickor och håligheter i magmatiska och vulkaniska bergarter. Detta kan spela stor roll framöver för studiet av djupbiosfären och det tidiga livet på jorden samt även för sökandet efter liv på Mars.

  • 15.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. University of Southern Denmark, Department of Biology and Nordic Center for Earth Evolution, Campusvej 55, Odense M, DK-5230, Denmark.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Drake, Henrik
    Linnaeus University, Kalmar.
    Francis, Warren
    University of Southern Denmark.
    Fungi in deep subsurface environments2018In: Advances in Applied Microbiology, ISSN 0065-2164, Vol. 102, p. 83-116Article in journal (Refereed)
    Abstract [en]

    The igneous crust of the oceans and the continents represents the major part of Earth's lithosphere and has recently been recognized as a substantial, yet underexplored, microbial habitat. While prokaryotes have been the focus of most investigations, microeukaryotes have been surprisingly neglected. However, recent work acknowledges eukaryotes, and in particular fungi, as common inhabitants of the deep biosphere, including the deep igneous provinces. The fossil record of the subseafloor igneous crust, and to some extent the continental bedrock, establishes fungi or fungus-like organisms as inhabitants of deep rock since at least the Paleoproterozoic, which challenges the present notion of early fungal evolution. Additionally, deep fungi have been shown to play an important ecological role engaging in symbiosis-like relationships with prokaryotes, decomposing organic matter, and being responsible for mineral weathering and formation, thus mediating mobilization of biogeochemically important elements. In this review, we aim at covering the abundance and diversity of fungi in the various igneous rock provinces on Earth as well as describing the ecological impact of deep fungi. We further discuss what consequences recent findings might have for the understanding of the fungal distribution in extensive anoxic environments and for early fungal evolution.

  • 16.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Neubeck, Anna
    Swedish Museum of Natural History, Department of Paleobiology. Stockholm University.
    The igneous oceanic crust – Earth’s largest fungal habitat?2016In: Fungal ecology, ISSN 1754-5048, E-ISSN 1878-0083, Vol. 20, p. 249-255Article in journal (Refereed)
    Abstract [en]

    In recent years the igneous oceanic crust has been recognized as a substantial microbial habitat and a scientific frontier within Geology, Biology, and Oceanography. A few successful metagenomic investigations have indicated the presence of Archaea and Bacteria, but also fungi in the subseafloor igneous crust. A comprehensive fossil record supports the presence of fungi in these deep environments and provides means of investigating the fungal presence that complements metagenomic methods. Considering the vast volume of the oceanic crust and that it is the largest aquifer on Earth, we put forward that it is the largest fungal habitat on the planet. This review aims to introduce a yet unexplored fungal habitat in an environment considered extreme from a biological perspective. We present the current knowledge of fungal abundance and diversity and discuss the ecological role of fungi in the igneous oceanic crust.

  • 17.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Skogby, Henrik
    Swedish Museum of Natural History, Department of Geology.
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Marone, Federica
    Paul Scherrer Institute.
    Fungal colonies in open fractures of subseafloor basalt.2013In: Geo-Marine Letters, ISSN 0276-0460, E-ISSN 1432-1157, Vol. 33, no 4, p. 233-234Article in journal (Refereed)
    Abstract [en]

    The deep subseafloor crust is one of the few great frontiers of unknown biology on Earth and, still today, the notion of the deep biosphere is commonly based on the fossil record. Interpretation of palaeobiological information is thus central in the exploration of this hidden biosphere and, for each new discovery, criteria used to establish biogenicity are challenged and need careful consideration. In this paper networks of fossilized filamentous structures are for the first time described in open fractures of subseafloor basalts collected at the Emperor Seamounts, Pacific Ocean. These structures have been investigated with optical microscopy, environmental scanning electron microscope, energy dispersive spectrometer, X-ray powder diffraction as well as synchrotron-radiation X-ray tomographic microscopy, and interpreted as fossilized fungal mycelia.Morphological features such as hyphae, yeastlike growth and sclerotia were observed. The fossilized fungi are mineralized by montmorillonite, a process that probably began while the fungi were alive. It seems plausible that the fungi produced mucilaginous polysaccharides and/or extracellular polymeric substances that attracted minerals or clay particles, resulting in complete fossilization by montmorillonite. The findings are in agreement with previous observations of fossilized fungi in subseafloor basalts and establish fungi as regular inhabitants of such settings. They further show that fossilized microorganisms are not restricted to pore spaces filled by secondary mineralizations but can be found in open pore spaces as well. This challenges standard protocols for establishing biogenicity and calls for extra care in data interpretation.

  • 18.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Bengtson, Stefan
    Skogby, Henrik
    Lazor, Peter
    Broman, Curt
    Belivanova, Veneta
    Marone, Federica
    A fungal-prokaryotic consortium at the basalt-zeolite interface in subseafloor igneous crust2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203Article in journal (Refereed)
  • 19. Ivarsson, Magnus
    et al.
    Broman, Curt
    Håkan, Gustafsson
    Holm, Nils
    Biogenic Mn-oxides in subseafloor basalts2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203Article in journal (Refereed)
  • 20.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Broman, Curt
    Sturkell, Erik
    Ormö, Jens
    Siljeström, Sandra
    van Zuilen, Mark
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Fungal colonization of an Ordovician impact-induced hydrothermal system.2013In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 3, no 3487, p. 1-6Article in journal (Refereed)
  • 21.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Gustavsson, Lena
    Swedish Museum of Natural History, Department of Zoology.
    Hedenäs, Lars
    Swedish Museum of Natural History, Department of Botany.
    Kronestedt, Torbjörn
    Swedish Museum of Natural History, Department of Zoology.
    Lundberg, Johannes
    Swedish Museum of Natural History, Department of Botany.
    Norbäck Ivarsson, Lena
    Södertörn University.
    Sallstedt, Therese
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Scheuerer, Manuela
    Sweco Rail.
    Thureborn, Olle
    Stockholm University.
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Unikt ekosystem i tunnelbanan vid Kungsträdgården2017In: Fauna och flora : populär tidskrift för biologi, ISSN 0014-8903, Vol. 112, no 1, p. 2-9Article in journal (Other (popular science, discussion, etc.))
  • 22.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Holm, Nils
    Neubeck, Anna
    The deep biosphere of the subseafloor igneous crust2015In: Trace Metal Biogeochemsitry and Ecology of Deep-Sea Hydrothermal Vent Systems / [ed] Demina, L.L., Galkin, S.V., Springer, 2015Chapter in book (Refereed)
  • 23.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Peckmann, J
    Swedish Museum of Natural History, Department of Paleobiology.
    Tehler, Anders
    Swedish Museum of Natural History, Department of Botany.
    Broman, C
    Bach, W
    Behrens, K
    Reitner, J
    Bottcher, M.E
    Norback Ivarsson, L
    Zygomycetes in Vesicular Basanites from Vesteris Seamount, Greenland Basin - A New Type of Cryptoendolithic Fungi2015In: PLoS One, Vol. 10, article id e0133368Article in journal (Refereed)
    Abstract [en]

    Fungi have been recognized as a frequent colonizer of subseafloor basalt but a substantial understanding of their abundance, diversity and ecological role in this environment is still lacking. Here we report fossilized cryptoendolithic fungal communities represented by mainly Zygomycetes and minor Ascomycetes in vesicles of dredged volcanic rocks (basa- nites) from the Vesteris Seamount in the Greenland Basin. Zygomycetes had not been reported from subseafloor basalt previously. Different stages in zygospore formation are documented in the studied samples, representing a reproduction cycle. Spore structures of both Zygomycetes and Ascomycetes are mineralized by romanechite-like Mn oxide phases, indicating an involvement in Mn(II) oxidation to form Mn(III,VI) oxides. Zygospores still exhibit a core of carbonaceous matter due to their resistance to degradation. The fungi are closely associated with fossiliferous marine sediments that have been introduced into the vesicles. At the contact to sediment infillings, fungi produced haustoria that penetrated and scavenged on the remains of fragmented marine organisms. It is most likely that such marine debris is the main carbon source for fungi in shallow volcanic rocks, which favored the establishment of vital colonies. 

  • 24.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Schnürer, Anna
    Swedish University of Agricultural Sciences.
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Neubeck, Anna
    Swedish Museum of Natural History, Department of Paleobiology. Stockholm University.
    Anaerobic fungi: a potential source of biological H2 in the oceanic crust.2016In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 7, no 674, p. 1-8Article in journal (Refereed)
    Abstract [en]

    The recent recognition of fungi in the oceanic igneous crust challenges the understanding of this environment as being exclusively prokaryotic and forces reconsiderations of the ecology of the deep biosphere. Anoxic provinces in the igneous crust are abundant and increase with age and depth of the crust. The presence of anaerobic fungi in deep-sea sediments and on the seafloor introduces a type of organism with attributes of geobiological significance not previously accounted for. Anaerobic fungi are best known from the rumen of herbivores where they produce molecular hydrogen, which in turn stimulates the growth of methanogens. The symbiotic cooperation between anaerobic fungi and methanogens in the rumen enhance the metabolic rate and growth of both. Methanogens and other hydrogen-consuming anaerobic archaea are known from subseafloor basalt; however, the abiotic production of hydrogen is questioned to be sufficient to support such communities. Alternatively, biologically produced hydrogen could serve as a continuous source. Here, we propose anaerobic fungi as a source of bioavailable hydrogen in the oceanic crust, and a close interplay between anaerobic fungi and hydrogen-driven prokaryotes.

  • 25.
    Ivarsson, Magnus
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. University of Southern Denmark, Department of Biology and Nordic Center for Earth Evolution, Campusvej 55, Odense M, DK-5230, Denmark.
    Skogby, Henrik
    Swedish Museum of Natural History, Department of Geology.
    Phichaikamjornwut, Bongkot
    Gems and Jewelry Program, Faculty of Science, Srinakharinwirot University, Bangkok, Thailand .
    Bengtson, Stefan
    Swedish Museum of Natural History, Department of Paleobiology.
    Siljeström, Sandra
    RISE Research Institutes of Sweden, Bioscience and Materials/Chemistry and Materials, Stockholm, Sweden.
    Ounchanum, Prayote
    Department of Geological Sciences, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand.
    Boonsong, Apichet
    Department of Geological Sciences, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand.
    Kruachanta, M
    Department of Geological Sciences, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand .
    Marone, Federica
    Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland.
    Belivanova, Veneta
    Swedish Museum of Natural History, Department of Paleobiology.
    Sara, Holmström
    Stockholm University, Department of Geological Sciences, Stockholm, Sweden.
    Intricate tunnels in garnets from soils and rivere sediments in Thailand - possible endolithic microborings2018In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 13, no 8, article id e0200351Article in journal (Refereed)
    Abstract [en]

    Garnets from disparate geographical environments and origins such as oxidized soils and river sediments in Thailand host intricate systems of microsized tunnels that significantly decrease the quality and value of the garnets as gems. The origin of such tunneling has previously been attributed to abiotic processes. Here we present physical and chemical remains of endolithic microorganisms within the tunnels and discuss a probable biological origin of the tunnels. Extensive investigations with synchrotron-radiation X-ray tomographic microscopy (SRXTM) reveal morphological indications of biogenicity that further support a euendolithic interpretation. We suggest that the production of the tunnels was initiated by a combination of abiotic and biological processes, and that at later stages biological processes came to dominate. In environments such as river sediments and oxidized soils garnets are among the few remaining sources of bio-available Fe2+, thus it is likely that microbially mediated boring of the garnets has trophic reasons. Whatever the reason for garnet boring, the tunnel system represents a new endolithic habitat in a hard silicate mineral otherwise known to be resistant to abrasion and chemical attack.

  • 26. Jackson, Marie
    et al.
    Gudmundson, Magnus
    Bach, Wolfgang
    Cappeletti, P
    Coleman, Nicole
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Jonasson, K
    Jörgensen, Steffen
    Marteinson, M.L.
    McPhie, V.
    Moore, James
    Nielson, Daniel
    Rhodes, J.
    Rispoli, C
    Schiffman, Peter
    Stefansson, Andri
    Turke, Andreas
    Vanorio, T
    Weisenberg, T.B.
    White, James
    Zierenberg, R.
    Zimanowski, B
    Time-lapse characterization of hydrothermal seawater and microbial interactions with basaltic tephra at Surtsey volcano2015In: Scientific Drilling, ISSN 1816-8957, E-ISSN 1816-3459, Vol. 20, p. 51-58Article in journal (Refereed)
    Abstract [en]

    A new International Continental Drilling Program (ICDP) project will drill through the 50-yearold edifice of Surtsey Volcano, the youngest of the Vestmannaeyjar Islands along the south coast of Iceland, to perform interdisciplinary time-lapse investigations of hydrothermal and microbial interactions with basaltic tephra. The volcano, created in 1963–1967 by submarine and subaerial basaltic eruptions, was first drilled in 1979. In October 2014, a workshop funded by the ICDP convened 24 scientists from 10 countries for 3 and a half days on Heimaey Island to develop scientific objectives, site the drill holes, and organize logistical support. Representatives of the Surtsey Research Society and Environment Agency of Iceland also participated. Scientific themes focus on further determinations of the structure and eruptive processes of the type locality of Surtseyan volcanism, descriptions of changes in fluid geochemistry and microbial colonization of the subterrestrial deposits since drilling 35 years ago, and monitoring the evolution of hydrothermal and biological processes within the tephra deposits far into the future through the installation of a Surtsey subsurface observatory. The tephra deposits provide a geologic analog for developing specialty concretes with pyroclastic rock and evaluating their long-term performance under diverse hydrothermal conditions.

  • 27.
    Neubeck, Anna
    et al.
    Department of Geological Sciences, Stockholm University, Stockholm.
    Sun, L
    Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala.
    Muller, B
    Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Hosgörmez, Hakan
    Department of Geological Engineering, Istanbul University, Istanbul.
    Özcan, D
    Department of Geological Engineering, Istanbul University, Istanbul.
    Broman, Curt
    Department of Geological Sciences, Stockholm University, Stockholm.
    Schnurer, Anna
    Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala.
    Microbial community structure of a serpentine-hosted abiotic gas seepage at the Chimaera ophiolite,Turkey2017In: Applied and Environmental Microbiology, ISSN 0099-2240, Vol. 83, no 12, article id e03430-16Article in journal (Refereed)
    Abstract [en]

    The surface waters at the ultramafic ophiolitic outcrop in Chimaera, Turkey, are characterized by high pH values and high metal levels due to the percolation of fluids through areas of active serpentinization. We describe the influence of the liquid chemistry, mineralogy, and H2 and CH4 levels on the bacterial community structure in a semidry, exposed, ultramafic environment. The bacterial and archaeal community structures were monitored using Illumina sequencing targeting the 16S rRNA gene. At all sampling points, four phyla, Proteobacteria, Actinobacteria, Chloroflexi, and Acidobacteria, accounted for the majority of taxa. Members of the Chloroflexi phylum dominated low-diversity sites, whereas Proteobacteria dominated high-diversity sites. Methane, nitrogen, iron, and hydrogen oxidizers were detected as well as archaea and metal-resistant bacteria. IMPORTANCE Our study is a comprehensive microbial investigation of the Chimaera ophiolite. DNA has been extracted from 16 sites in the area and has been studied from microbial and geochemical points of view. We describe a microbial community structure that is dependent on terrestrial, serpentinization-driven abiotic H2, which is poorly studied due to the rarity of these environments on Earth.

  • 28. Neubeck, Anna
    et al.
    Tulej, Marek
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Broman, Curt
    Riedo, Andreas
    Wurz, Peter
    Bengtson, Stefan
    McMahon, Sean
    Mineralogical determination in situ of a highly heterogenous material using miniaturized laser ablation mass spectrometer with high spatial resolution2015In: International Journal of Astrobiology, ISSN 1473-5504, E-ISSN 1475-3006Article in journal (Refereed)
  • 29.
    Réblová, Martina
    et al.
    Department of Taxonomy, Institute of Botany of the Czech Academy of Sciences, 252 43, Pruhonice, Czech Republic.
    Hubka, Vit
    Department of Botany, Faculty of Science, Charles University in Prague, Benatska 2, 128 01 Prague 2, Czech Republic.
    Thureborn, Olle
    Institutionen för ekologi miljö och botanik, Stockholms Universitet.
    Lundberg, Johannes
    Swedish Museum of Natural History, Department of Botany.
    Sallstedt, Therese
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Wedin, Mats
    Swedish Museum of Natural History, Department of Botany.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    From the tunnels into the treetops: new lineages of black yeasts from biofilm in the Stockholm metro system and their relatives among ant-associated fungi in the Chaetothyriales2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 10, p. e0163396-, article id e0163396Article in journal (Refereed)
    Abstract [en]

    Rock-inhabiting fungi harbour species-rich, poorly differentiated, extremophilic taxa of polyphyletic origin. Their closest relatives are often well-known species from various biotopes with significant pathogenic potential. Speleothems represent a unique rock-dwelling habitat, whose mycobiota are largely unexplored. Isolation of fungi from speleothem biofilm covering bare granite walls in the Kungsträdgården metro station in Stockholm yielded axenic cultures of two distinct black yeast morphotypes. Phylogenetic analyses of DNA sequences from six nuclear loci, ITS, nuc18S and nuc28S rDNA, rpb1, rpb2 and β-tubulin, support their placement in the Chaetothyriales (Ascomycota). They are described as a new genus Bacillicladium with the type species Blobatum, and a new species Bradymyces graniticolaBacillicladium is distantly related to the known five chaetothyrialean families and is unique in the Chaetothyriales by variable morphology showing hyphal, meristematic and yeast-like growth in vitro. The nearest relatives of Bacillicladium are recruited among fungi isolated from cardboard-like construction material produced by arboricolous non-attine ants. Their sister relationship is weakly supported by the Maximum likelihood analysis, but strongly supported by Bayesian inference. The genus Bradymyces is placed amidst members of the Trichomeriaceae and is ecologically undefined; it includes an opportunistic animal pathogen while two other species inhabit rock surfaces. ITS rDNA sequences of three species accepted in Bradymyces and other undescribed species and environmental samples were subjected to phylogenetic analysis and in-depth comparative analysis of ITS1 and ITS2 secondary structures in order to study their intraspecific variability. Compensatory base change criterion in the ITS2 secondary structure supported delimitation of species in Bradymyces, which manifest a limited number of phenotypic features useful for species recognition. The role of fungi in the speleothem biofilm and relationships of Bacillicladium and Bradymyces with other members of the Chaetothyriales are discussed.

  • 30.
    Sallstedt, Therese
    et al.
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE); Department of Biology, University of Southern Denmark.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Lundberg, Johannes
    Swedish Museum of Natural History, Department of Botany.
    Sjöberg, Rabbe
    Vidal Romaní, Juan Ramón
    University of Coruña, Campus de Elviña, ES-15071 Coruña, Spain.
    Speleothem and biofilm formation in a granite/dolerite cave, Northern Sweden2014In: International Journal of Speleology, ISSN 0392-6672, E-ISSN 1827-806X, Vol. 43, no 3, p. 305-313Article in journal (Refereed)
    Abstract [en]

    Tjuv-Antes grotta (Tjuv-Ante's Cave) located in northern Sweden is a round-abraded sea cave ('tunnel cave'), about 30 m in length, formed by rock-water abrasion in a dolerite dyke in granite gneiss. Abundant speleothems are restricted to the inner, mafic parts of the cave and absent on granite parts. The speleothems are of two types: cylindrical (coralloid, popcorn-like), and flowstone (thin crusts). Coralloids correspond to terrestrial stromatolite speleothems in which layers of light calcite alternate with dark, silica-rich laminae. The dark laminae are also enriched in carbon and contain incorporated remains of microorganisms. Two types of microbial communities can be distinguished associated with the speleothems: an Actinobacteria-like biofilm and a fungal community. Actinobacteria seem to play an important role in the formation of speleothem while the fungal community acts as both a constructive and a destructive agent. A modern biofilm dominated by Actinobacteria is present in the speleothem-free parts of the dolerite and located in cave ceiling cracks. These biofilms may represent sites of early speleothem formation. Because of its unusual position in between two types of host rock, Tjuv-Ante's Cave represents a unique environment in which to study differences in microbe-rock interactions and speleothem genesis between the granite and dolerite host rock. Our study shows that the mafic rock is superior to the granite in hosting a microbial community and to support formation of speleothems.

  • 31.
    Sjöberg, Susanne
    et al.
    Department of Geological Sciences, Stockholm University, Stockholm.
    Allard, Bert
    Man-Technology-Environment Research Centre, Örebro University, Örebro.
    Rattray, Jane
    Department of Geological Sciences, Stockholm University, Stockholm.
    Callac, Nolwenn
    Department of Geological Sciences, Stockholm University, Stockholm.
    Grawunder, Anja
    Institute of Geosciences, Friedrich Schiller University of Jena, Jena.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Sjöberg, Viktor
    Man-Technology-Environment Research Centre, Örebro University, Örebro.
    Karlsson, Stefan
    Man-Technology-Environment Research Centre, Örebro University, Örebro.
    Skelton, Alasdair
    Department of Geological Sciences, Stockholm University, Stockholm.
    Dupraz, C
    Department of Geological Sciences, Stockholm University, Stockholm.
    Rare Earth element enriched birnessite in water-bearing fractures, the Ytterby mine, Sweden2017In: Applied Geochemistry, ISSN 0883-2827, Vol. 78, p. 158-171Article in journal (Refereed)
    Abstract [en]

    Characterization of a black substance exuding from fractured bedrock in a subterranean tunnel revealed a secondary manganese oxide mineralisation exceptionally enriched in rare earth elements (REE). Concentrations are among the highest observed in secondary ferromanganese precipitates in nature. The tunnel is located in the unsaturated zone at shallow depth in the former Ytterby mine, known for the discovery of yttrium, scandium, tantalum and five rare earth elements.

    Elemental analysis and X-ray diffraction of the black substance establish that the main component is a manganese oxide of the birnessite type. Minor fractions of calcite, other manganese oxides, feldspars, quartz and about 1% organic matter were also found, but no iron oxides were identified. The Ytterby birnessite contains REE, as well as calcium, magnesium and traces of other metals. The REE, which constitute 1% of the dry mass and 2% of the metal content, are firmly included in the mineral structure and are not released by leaching at pH 1.5 or higher. A strong preference for the trivalent REE over divalent and monovalent metals is indicated by concentration ratios of the substance to fracture water. The REE-enriched birnessite has the general formula Mx(Mn3+,Mn4+)2O4·(H2O)n with M = (0.37–0.41) Ca + 0.02 (REE + Y), 0.04 Mg and (0.02–0.03) other metals, and with [Mn3+]/[Mn4+] = 0.86–1.00.

    The influence of microorganisms on the accumulation of this REE enriched substance is demonstrated by electron paramagnetic resonance spectroscopy. Results show that it is composed of two or more manganese phases, one of which has a biogenic signature. In addition, the occurrence of C31 to C35 extended side chain hopanoids among the identified lipid biomarkers combined with the absence of ergosterol, a fungal lipid biomarker, indicate that the in-situ microbial community is bacterial rather than fungal.

  • 32. Tulej, Marek
    et al.
    Neubeck, Anna
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology.
    Riedo, Andreas
    Neuland, M.
    Meyer, Stephan
    Wurz, Peter
    Chemical composition of micrometer-sized filaments in an aragonite host by a miniature laser ablation/ionization mass spectrometer2015In: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070, Vol. 15, p. 669-682Article in journal (Refereed)
  • 33. Tulej, Marek
    et al.
    Riedo, Andreas
    Neuland, Maike
    Meyer, Stefan
    Wurz, Peter
    Thomas, Nicolas
    Grimaudo, Valentine
    Moreno-Garcia, Pavel
    Broekmann, Peter
    Neubeck, Anna
    Ivarsson, Magnus
    CAMAM: a miniature laser ablation ionization mass spectrometer and camera-microscope system for in situ investigation of the composition and morphology of extraterrestrial materials2014In: Geostandards and Geoanalytical Research, ISSN 1639-4488, E-ISSN 1751-908X, Vol. 38, p. 441-466Article in journal (Refereed)
  • 34.
    Wiesendanger, Reto
    et al.
    Research and Planetary Sciences Physics Institute University of Bern Sidlerstrasse 5Bern CH-3012 Switzerland.
    Wacey, David
    Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Perth, Australia.
    Tulej, Marek
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Neubeck, Anna
    Swedish Museum of Natural History, Department of Paleobiology.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology. University of Southern Denmark, Department of Biology and Nordic Center for Earth Evolution, Campusvej 55, Odense M, DK-5230, Denmark.
    Grimaudo, V.
    Department of Chemistry and Biochemistry, Interfacial Electrochemistry Group, University of Bern, Bern, Switzerland.
    Moreno-Garcia, P.
    Department of Chemistry and Biochemistry, Interfacial Electrochemistry Group, University of Bern, Bern, Switzerland.
    Cedeῆo López, A.
    Department of Chemistry and Biochemistry, Interfacial Electrochemistry Group, University of Bern, Bern, Switzerland.
    Riedo, Andreas
    Sackler Laboratory for Astrophysics, Leiden Observatory, Leiden University, The Netherlands.
    Wurz, Peter
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Chemical and optical identification of micrometer sized 1.9 Ga old fossils with a miniature LIMS system combined with an optical microscope2018In: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070, Vol. 18, no 8, p. 1071-1080Article in journal (Refereed)
    Abstract [en]

    The recognition of biosignatures on planetary bodies requires the analysis of the putative microfossil with a set of complementary analytical techniques. This includes localized elemental and isotopic analysis of both the putative microfossil and its surrounding host matrix. If the analysis can be performed with spatial resolution at the micrometer level and part-per-million detection sensitivities, valuable information on the (bio)chemical and physical processes that influenced the sample material can be gained. Our miniaturized laser ablation ionization mass spectrometry (LIMS)-time-of-flight mass spectrometer instrument is a valid candidate for performing the required chemical analysis in situ. However, up until now it was limited by the spatial accuracy of the sampling. In this contribution, we introduce a newly developed microscope system with micrometer accuracy for ultra high vacuum application, which allows a significant increase in the measurement capabilities of our miniature LIMS system. The new enhancement allows identification and efficient and accurate sampling of features of micrometer-sized fossils in a host matrix. The performance of our system is demonstrated by the identification and chemical analysis of signatures of micrometer-sized fossil structures in the 1.9 billion-year-old Gunflint chert.

  • 35.
    Zepeda Mendoza, Marie Lisandra
    et al.
    Natural History Museum of Denmark.
    Lundberg, Johannes
    Swedish Museum of Natural History, Department of Botany.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Campos, Paula
    University of Copenhagen.
    Nylander, Johan A. A.
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Sallstedt, Thereese
    Swedish Museum of Natural History, Department of Paleobiology. Nordic Center for Earth Evolution (NordCEE).
    Dalén, Love
    Swedish Museum of Natural History, Department of Bioinformatics and Genetics.
    Metagenomic Analysis from the Interior of a Speleothem in Tjuv-Ante's Cave, Northern Sweden2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 3, p. 1-23, article id e015177Article in journal (Refereed)
    Abstract [en]

    Speleothems are secondary mineral deposits normally formed by water supersaturated with calcium carbonate percolating into underground caves, and are often associated with low-nutrient and mostly non-phototrophic conditions. Tjuv-Ante’s cave is a shallow-depth cave formed by the action of waves, with granite and dolerite as major components, and opal-A and calcite as part of the speleothems, making it a rare kind of cave. We generated two DNA shotgun sequencing metagenomic datasets from the interior of a speleothem from Tjuv-Ante’s cave representing areas of old and relatively recent speleothem formation. We used these datasets to perform i) an evaluation of the use of these speleothems as past biodiversity archives, ii) functional and taxonomic profiling of the speleothem’s different formation periods, and iii) taxonomic comparison of the metagenomic results to previous microscopic analyses from a nearby speleothem of the same cave. Our analyses confirm the abundance of Actinobacteria and fungi as previously reported by microscopic analyses on this cave, however we also discovered a larger biodiversity. Interestingly, we identified photosynthetic genes, as well as genes related to iron and sulphur metabolism, suggesting the presence of chemoautotrophs. Furthermore, we identified taxa and functions related to biomineralization. However, we could not confidently establish the use of this type of speleothems as biological paleoarchives due to the potential leaching from the outside of the cave and the DNA damage that we propose has been caused by the fungal chemical etching.

1 - 35 of 35
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf