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  • 1.
    Bengtson, Stefan
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Astolfo, Alberto
    Paul Scherrer Institute.
    Belivanova, Veneta
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    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.2014Ingår i: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 12, nr 6, s. 489-496Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 2. Chi Fru, E.
    et al.
    Ivarsson, M.
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    Kilias, S. P.
    Frings, Patrick J
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    Hemmingsson, C.
    Broman, C.
    Bengtson, S.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Chatzitheodoridis, E.
    Biogenicity of an Early Quaternary iron formation, Milos Island, Greece2015Ingår i: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 13, nr 3, s. 225-244Artikel i tidskrift (Refereegranskat)
    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.

  • 3. Chi Fru, Ernest
    et al.
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Kilias, Stephanos
    Christoffer, Hemmingson
    Broman, Curt
    Bengtson, Stefan
    C, Chatzitheodoridis
    Biogenicity of an early Quaternary iron formation, Milos Island, Greece2015Ingår i: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 13, s. 225-244Artikel i tidskrift (Refereegranskat)
  • 4. Chi Fru, Ernest
    et al.
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Kilias, Stephanos P
    Bengtson, Stefan
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Belivanova, Veneta
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    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.2013Ingår i: Nature Communications, ISSN 2041-1723, Vol. 4, nr 2050, s. 1-7Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    ChiFru_etal_2013_BIF_MS
  • 5. 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 granite2015Ingår i: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 6Artikel i tidskrift (Refereegranskat)
  • 6.
    Ivarsson, Lena Norbäck
    et al.
    Stockholm University.
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Lundberg, Johannes
    Naturhistoriska riksmuseet, Enheten för botanik.
    Sallstedt, Therese
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Rydin, Catarina
    Stockholm University.
    Epilithic and aerophilic diatoms in the artificial environment of Kungsträdgården metro station, Stockholm, Sweden2013Ingår i: International Journal of Speleology, ISSN 0392-6672, E-ISSN 1827-806X, Vol. 42, nr 3, s. 289-297Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    Diatoms in Kungsträdgården metro station.pdf
  • 7.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bengtson, Stefan
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Belivanova, Veneta
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Stampanoni, Marco
    ETH Zürich.
    Marone, Federica
    Paul Scherrer Institute.
    Tehler, Anders
    Naturhistoriska riksmuseet, Enheten för botanik.
    Fossilized fungi in subseafloor Eocene basalts.2012Ingår i: Geology, ISSN 0091-7613, Vol. 40, nr 2, s. 163-166Artikel i tidskrift (Refereegranskat)
    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.

  • 8.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bengtson, Stefan
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Neubeck, Anna
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Stockholm University.
    The igneous oceanic crust – Earth’s largest fungal habitat?2016Ingår i: Fungal ecology, ISSN 1754-5048, E-ISSN 1878-0083, Vol. 20, s. 249-255Artikel i tidskrift (Refereegranskat)
    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.

  • 9.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bengtson, Stefan
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Skogby, Henrik
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    Belivanova, Veneta
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Marone, Federica
    Paul Scherrer Institute.
    Fungal colonies in open fractures of subseafloor basalt.2013Ingår i: Geo-Marine Letters, ISSN 0276-0460, E-ISSN 1432-1157, Vol. 33, nr 4, s. 233-234Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    Ivarsson_etal_2013_Fungal
  • 10.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Bengtson, Stefan
    Skogby, Henrik
    Lazor, Peter
    Broman, Curt
    Belivanova, Veneta
    Marone, Federica
    A fungal-prokaryotic consortium at the basalt-zeolite interface in subseafloor igneous crust2015Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203Artikel i tidskrift (Refereegranskat)
  • 11. Ivarsson, Magnus
    et al.
    Broman, Curt
    Håkan, Gustafsson
    Holm, Nils
    Biogenic Mn-oxides in subseafloor basalts2015Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203Artikel i tidskrift (Refereegranskat)
  • 12.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Broman, Curt
    Sturkell, Erik
    Ormö, Jens
    Siljeström, Sandra
    van Zuilen, Mark
    Bengtson, Stefan
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Fungal colonization of an Ordovician impact-induced hydrothermal system.2013Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 3, nr 3487, s. 1-6Artikel i tidskrift (Refereegranskat)
    Ladda ner fulltext (pdf)
    Ivarsson et al. 2013
  • 13.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Nordic Center for Earth Evolution (NordCEE).
    Gustavsson, Lena
    Naturhistoriska riksmuseet, Enheten för zoologi.
    Hedenäs, Lars
    Naturhistoriska riksmuseet, Enheten för botanik.
    Kronestedt, Torbjörn
    Naturhistoriska riksmuseet, Enheten för zoologi.
    Lundberg, Johannes
    Naturhistoriska riksmuseet, Enheten för botanik.
    Norbäck Ivarsson, Lena
    Södertörn University.
    Sallstedt, Therese
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Nordic Center for Earth Evolution (NordCEE).
    Scheuerer, Manuela
    Sweco Rail.
    Thureborn, Olle
    Stockholm University.
    Wedin, Mats
    Naturhistoriska riksmuseet, Enheten för botanik.
    Unikt ekosystem i tunnelbanan vid Kungsträdgården2017Ingår i: Fauna och flora : populär tidskrift för biologi, ISSN 0014-8903, Vol. 112, nr 1, s. 2-9Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Ladda ner fulltext (pdf)
    fulltext
  • 14.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Holm, Nils
    Neubeck, Anna
    The deep biosphere of the subseafloor igneous crust2015Ingår i: Trace Metal Biogeochemsitry and Ecology of Deep-Sea Hydrothermal Vent Systems / [ed] Demina, L.L., Galkin, S.V., Springer, 2015Kapitel i bok, del av antologi (Refereegranskat)
  • 15.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Peckmann, J
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Tehler, Anders
    Naturhistoriska riksmuseet, Enheten för botanik.
    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 Fungi2015Ingår i: PLoS One, Vol. 10, artikel-id e0133368Artikel i tidskrift (Refereegranskat)
    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. 

    Ladda ner fulltext (pdf)
    fulltext
  • 16.
    Ivarsson, Magnus
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Schnürer, Anna
    Swedish University of Agricultural Sciences.
    Bengtson, Stefan
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Neubeck, Anna
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Stockholm University.
    Anaerobic fungi: a potential source of biological H2 in the oceanic crust.2016Ingår i: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 7, nr 674, s. 1-8Artikel i tidskrift (Refereegranskat)
    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.

  • 17. Jackson, Marie
    et al.
    Gudmundson, Magnus
    Bach, Wolfgang
    Cappeletti, P
    Coleman, Nicole
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    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 volcano2015Ingår i: Scientific Drilling, ISSN 1816-8957, E-ISSN 1816-3459, Vol. 20, s. 51-58Artikel i tidskrift (Refereegranskat)
    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.

  • 18. Neubeck, Anna
    et al.
    Tulej, Marek
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    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 resolution2015Ingår i: International Journal of Astrobiology, ISSN 1473-5504, E-ISSN 1475-3006Artikel i tidskrift (Refereegranskat)
  • 19.
    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
    Naturhistoriska riksmuseet, Enheten för botanik.
    Sallstedt, Therese
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Nordic Center for Earth Evolution (NordCEE).
    Wedin, Mats
    Naturhistoriska riksmuseet, Enheten för botanik.
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi. 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 Chaetothyriales2016Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, nr 10, s. e0163396-, artikel-id e0163396Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 20.
    Sallstedt, Therese
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Nordic Center for Earth Evolution (NordCEE); Department of Biology, University of Southern Denmark.
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Nordic Center for Earth Evolution (NordCEE).
    Lundberg, Johannes
    Naturhistoriska riksmuseet, Enheten för botanik.
    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 Sweden2014Ingår i: International Journal of Speleology, ISSN 0392-6672, E-ISSN 1827-806X, Vol. 43, nr 3, s. 305-313Artikel i tidskrift (Refereegranskat)
    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.

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    Sallstedt et al 2014 Int J Speleology
  • 21. Tulej, Marek
    et al.
    Neubeck, Anna
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    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 spectrometer2015Ingår i: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070, Vol. 15, s. 669-682Artikel i tidskrift (Refereegranskat)
  • 22. 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 materials2014Ingår i: Geostandards and Geoanalytical Research, ISSN 1639-4488, E-ISSN 1751-908X, Vol. 38, s. 441-466Artikel i tidskrift (Refereegranskat)
  • 23.
    Zepeda Mendoza, Marie Lisandra
    et al.
    Natural History Museum of Denmark.
    Lundberg, Johannes
    Naturhistoriska riksmuseet, Enheten för botanik.
    Ivarsson, Magnus
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Nordic Center for Earth Evolution (NordCEE).
    Campos, Paula
    University of Copenhagen.
    Nylander, Johan A. A.
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Sallstedt, Thereese
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Nordic Center for Earth Evolution (NordCEE).
    Dalén, Love
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Metagenomic Analysis from the Interior of a Speleothem in Tjuv-Ante's Cave, Northern Sweden2016Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, nr 3, s. 1-23, artikel-id e015177Artikel i tidskrift (Refereegranskat)
    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.

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    fulltext
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