89 research outputs found

    Recovering Greater Fungal Diversity from Pristine and Diesel Fuel Contaminated Sub-Antarctic Soil Through Cultivation Using Both a High and a Low Nutrient Media Approach

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    Novel cultivation strategies for bacteria are widespread and well described for recovering greater diversity from the “hitherto” unculturable majority. While similar approaches have not yet been demonstrated for fungi it has been suggested that of the 1.5 million estimated species less than 5% have been recovered into pure culture. Fungi are known to be involved in many degradative processes, including the breakdown of petroleum hydrocarbons, and it has been speculated that in Polar Regions they contribute significantly to bioremediation of contaminated soils. Given the biotechnological potential of fungi there is a need to increase efforts for greater species recovery, particularly from extreme environments such as sub-Antarctic Macquarie Island. In this study, like the yet-to-be cultured bacteria, high concentrations of nutrients selected for predominantly different fungal species to that recovered using a low nutrient media. By combining both media approaches to the cultivation of fungi from contaminated and non-contaminated soils, 91 fungal species were recovered, including 63 unidentified species. A preliminary biodegradation activity assay on a selection of isolates found that a high proportion of novel and described fungal species from a range of soil samples were capable of hydrocarbon degradation and should be characterized further

    Out of thin air? Astrobiology and atmospheric chemotrophy

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    The emerging understanding of microbial trace gas chemotrophy as a metabolic strategy to support energy and carbon acquisition for microbial survival and growth has significant implications in the search for past, and even extant, life beyond Earth. The use of trace gases, including hydrogen and carbon monoxide as substrates for microbial oxidation, potentially offers a viable strategy with which to support life on planetary bodies that possess a suitable atmospheric composition, such as Mars and Titan. Here, we discuss the current state of knowledge of this process and explore its potential in the field of astrobiological exploration.An Australian Research Council Future Fellowshiphttps://home.liebertpub.com/publications/astrobiology/99am2023BiochemistryGeneticsMicrobiology and Plant Patholog

    Microfluidic qPCR Enables High Throughput Quantification of Microbial Functional Genes but Requires Strict Curation of Primers

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    Quantification of microbial functional genes enhances predictions of soil biogeochemical process rates, but reliance on low-throughput quantitative PCR (qPCR) limits the scope of ecological studies to a handful of targets. Here, we explore whether microfluidic qPCR (MFQPCR) is a viable high-throughput alternative for functional gene quantification, by evaluating the efficiency, specificity and sensitivity of 29 established and 12 newly designed primer pairs targeting taxonomic, nitrogen-cycling, and hydrocarbon degradation genes in genomic DNA soil extracts, under three different sets of MFQPCR assay conditions. Without curation, commonly-used qPCR primer pairs yielded an extreme range of reaction efficiencies (25.9–100.1%), but when conditions were optimized, MFQPCR produced copy-number estimates comparable to traditional qPCR. To guide microbial soil ecologists considering adoption of MFQPCR, we present suggestions for primer selection, including omission of inosines, degeneracy scores of < 9, amplicon sizes of ≤ 211 bp, and GC content of 32–61%. We conclude that, while the nanoliter reaction volumes, rapid thermocycling and one-size-fits-all reaction conditions of MFQPCR necessitates more stringent primer selection criteria than is commonly applied in soil microbial ecology, the ability to quantify up to 96 targets in 96 samples makes MFQPCR a valuable tool for monitoring shifts in functional community abundances. MFQPCR will particularly suit studies targeting multiple clade-specific functional genes, or when primer design is informed by previous knowledge of the environment

    Metagenomics untangles potential adaptations of Antarctic endolithic bacteria at the fringe of habitability

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    Survival and growth strategies of Antarctic endolithic microbes residing in Earth's driest and coldest desert remain virtually unknown. From 109 endolithic microbiomes, 4539 metagenome-assembled genomes were generated, 49.3 % of which were novel candidate bacterial species. We present evidence that trace gas oxidation and atmospheric chemosynthesis may be the prevalent strategies supporting metabolic activity and persistence of these ecosystems at the fringe of life and the limits of habitabilit

    Distinct assembly mechanisms underlie similar biogeographical patterns of rare and abundant bacteria in Tibetan Plateau grassland soils

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    Rare biosphere represents the majority of Earth's biodiversity and performs vital ecological functions, yet little is known about its biogeographical patterns and community assembly processes in terrestrial ecosystems. Herein, we investigated the community composition and phylogeny of rare (relative abundance 1%) bacteria in dryland grassland soils on the Tibetan Plateau. Results revealed similar biogeographical patterns of rare and abundant bacteria at both compositional and phylogenetic levels, but rare subcommunity was more heavily influenced by stochasticity (72%) than the abundant (57%). The compositional variation of rare bacteria was less explained by environmental factors (41%) than that of the abundant (80%), while the phylogeny of rare bacteria (36%) was more explained than that of the abundant (29%). The phylogeny of rare bacteria was equally explained by local factors (soil and vegetation) and geospatial distance (11.5% and 11.9% respectively), while that of the abundant was more explained by geospatial distance (22.1%) than local factors (11.3%). Furthermore, a substantially tighter connection between the community phylogeny and composition was observed in rare (R2 = 0.65) than in abundant bacteria (R2 = 0.08). Our study provides novel insights into the assembly processes and biographical patterns of rare and abundant bacteria in dryland soils.Battelle Memorial Institute; Pacific Northwest National Laboratory; Office of Biological and Environmental Research; US Department of Energy (DOE); National Natural Science Foundation of China and Chinese Academy of Sciences.https://sfamjournals.onlinelibrary.wiley.com/journal/14622920hj2021Genetic

    Metagenomics untangles potential adaptations of Antarctic endolithic bacteria at the fringe of habitability

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    8 páginas.- 5 figuras.- 20 referencias.- Supplementary data to this article can be found online at https://doi.org/10.1016/j.scitotenv.2024.170290Survival and growth strategies of Antarctic endolithic microbes residing in Earth's driest and coldest desert remain virtually unknown. From 109 endolithic microbiomes, 4539 metagenome-assembled genomes were generated, 49.3 % of which were novel candidate bacterial species. We present evidence that trace gas oxidation and atmospheric chemosynthesis may be the prevalent strategies supporting metabolic activity and persistence of these ecosystems at the fringe of life and the limits of habitability.C.C. is supported by the European Commission under the H2020 Marie Skłodowska-Curie Actions Grant Agreement No. 702057 (DRYLIFE). C.C. and L.S. wish to thank the Italian National Program for Antarctic Research for funding sampling campaigns and research activities in Italy in the frame of PNRA projects. The Italian Antarctic National Museum (MNA) is kindly acknowledged for financial support to the Mycological Section of the MNA and for providing rock samples used in this study stored in the Culture Collection of Antarctic fungi (MNA-CCFEE), University of Tuscia, Italy. M.D-B. is supported by a project from the Spanish Ministry of Science and Innovation (PID2020-115813RA-I00), and a project of the Fondo Europeo de Desarrollo Regional (FEDER) and the Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014-2020 Objetivo temático ‘01 – Refuerzo de la investigación, el desarrollo tecnológico y la innovación’) associated with the research project P20_00879 (ANDABIOMA). J.E.S. is a CIFAR fellow in the Fungal Kingdom: Threats and Opportunities program. B.C.F. acknowledges support from the Australian Research Council Discovery Project (DP220103430). Part of this work (proposal 10.46936/10.25585/60000791) was conducted by the U.S. Department of Energy Joint Genome Institute (https://ror.org/04xm1d337), a DOE Office of Science User Facility, supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.Peer reviewe

    Introducing BASE: the Biomes of Australian Soil Environments soil microbial diversity database

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    Corrected by: Erratum: Introducing BASE: The Biomes of Australian Soil Environments soil microbial diversity database [GigaScience. 5, 1, (2016) (1-11)] DOI: 10.1186/s13742-016-0126-5. In GigaScience 6(5):1, the authorship list should have included Leon Court, who was responsible for sample collection and preparation, sampling design and sequencing method design. The authors regret this omission.BACKGROUND Microbial inhabitants of soils are important to ecosystem and planetary functions, yet there are large gaps in our knowledge of their diversity and ecology. The ‘Biomes of Australian Soil Environments’ (BASE) project has generated a database of microbial diversity with associated metadata across extensive environmental gradients at continental scale. As the characterisation of microbes rapidly expands, the BASE database provides an evolving platform for interrogating and integrating microbial diversity and function. FINDINGS BASE currently provides amplicon sequences and associated contextual data for over 900 sites encompassing all Australian states and territories, a wide variety of bioregions, vegetation and land-use types. Amplicons target bacteria, archaea and general and fungal-specific eukaryotes. The growing database will soon include metagenomics data. Data are provided in both raw sequence (FASTQ) and analysed OTU table formats and are accessed via the project’s data portal, which provides a user-friendly search tool to quickly identify samples of interest. Processed data can be visually interrogated and intersected with other Australian diversity and environmental data using tools developed by the ‘Atlas of Living Australia’. CONCLUSIONS Developed within an open data framework, the BASE project is the first Australian soil microbial diversity database. The database will grow and link to other global efforts to explore microbial, plant, animal, and marine biodiversity. Its design and open access nature ensures that BASE will evolve as a valuable tool for documenting an often overlooked component of biodiversity and the many microbe-driven processes that are essential to sustain soil function and ecosystem services.Andrew Bissett, Anna Fitzgerald, Thys Meintjes, Pauline M. Mele, Frank Reith, Paul G. Dennis, Martin F. Breed, Belinda Brown, Mark V. Brown, Joel Brugger, Margaret Byrne, Stefan Caddy-Retalic, Bernie Carmody, David J. Coates, Carolina Correa, Belinda C. Ferrari, Vadakattu V. S. R. Gupta, Kelly Hamonts, Asha Haslem, Philip Hugenholtz, Mirko Karan, Jason Koval, Andrew J. Lowe, Stuart Macdonald, Leanne McGrath, David Martin, Matt Morgan, Kristin I. North, Chanyarat Paungfoo-Lonhienne, Elise Pendall, Lori Phillips, Rebecca Pirzl, Jeff R. Powell, Mark A. Ragan, Susanne Schmidt, Nicole Seymour, Ian Snape, John R. Stephen, Matthew Stevens, Matt Tinning, Kristen Williams, Yun Kit Yeoh, Carla M. Zammit, and Andrew Youn

    Introducing BASE: the Biomes of Australian Soil Environments soil microbial diversity database

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    Background: Microbial inhabitants of soils are important to ecosystem and planetary functions, yet there are large gaps in our knowledge of their diversity and ecology. The 'Biomes of Australian Soil Environments' (BASE) project has generated a database of microbial diversity with associated metadata across extensive environmental gradients at continental scale. As the characterisation of microbes rapidly expands, the BASE database provides an evolving platform for interrogating and integrating microbial diversity and function. Findings: BASE currently provides amplicon sequences and associated contextual data for over 900 sites encompassing all Australian states and territories, a wide variety of bioregions, vegetation and land-use types. Amplicons target bacteria, archaea and general and fungal-specific eukaryotes. The growing database will soon include metagenomics data. Data are provided in both raw sequence (FASTQ) and analysed OTU table formats and are accessed via the project's data portal, which provides a user-friendly search tool to quickly identify samples of interest. Processed data can be visually interrogated and intersected with other Australian diversity and environmental data using tools developed by the 'Atlas of Living Australia'. Conclusions: Developed within an open data framework, the BASE project is the first Australian soil microbial diversity database. The database will grow and link to other global efforts to explore microbial, plant, animal, and marine biodiversity. Its design and open access nature ensures that BASE will evolve as a valuable tool for documenting an often overlooked component of biodiversity and the many microbe-driven processes that are essential to sustain soil function and ecosystem services

    Introducing BASE: the Biomes of Australian Soil Environments soil microbial diversity database

    Get PDF
    Microbial inhabitants of soils are important to ecosystem and planetary functions, yet there are large gaps in our knowledge of their diversity and ecology. The ‘Biomes of Australian Soil Environments’ (BASE) project has generated a database of microbial diversity with associated metadata across extensive environmental gradients at continental scale. As the characterisation of microbes rapidly expands, the BASE database provides an evolving platform for interrogating and integrating microbial diversity and function

    ‘No memory, no desire’: psychoanalysis in Brazil during repressive times

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    Until recently, the growth and significance of Brazilian psychoanalysis has been neglected in histories of psychoanalysis. Not only is this history long and rich in its professional and cultural dimensions, but there was an especially important ‘event’ – the so-called ‘Cabernite-Lobo affair’ – that took place during the period of the military dictatorship, which can be seen as dramatising some of the issues concerning the erasure of memory in psychoanalysis, especially in connection with political difficulties. In this paper, we provide an outline of the origins and dissemination of psychoanalysis in Brazil before looking again at the Cabernite-Lobo affair in order to examine in a situated way how psychoanalysis engages with political extremism, and particularly to explore the consequences of an unthinking generalisation of the idea of ‘neutrality’ from the consulting room to the institutional setting. We draw especially on Brazilian papers in Portuguese, which have not been accessible in the English-language psychoanalytic literature
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