199 research outputs found

    Water–Sulfuric Acid foam as a Possible Habitat for Hypothetical Microbial Community in the Cloud Layer of Venus

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    The data available at the moment suggest that ancient Venus was covered by extensive bodies of water which could harbor life. Later, however, the drastic overheating of the planet made the surface of Venus uninhabitable for Earth-type life forms. Nevertheless, hypothetical Venusian organisms could have gradually adapted to conditions within the cloud layer of Venus—the only niche containing liquid water where the Earth-type extremophiles could survive. Here we hypothesize that the unified internal volume of a microbial community habitat is represented by the heterophase liquid-gas foam structure of Venusian clouds. Such unity of internal space within foam water volume facilitates microbial cells movements and trophic interactions between microorganisms that creates favorable conditions for the effective development of a true microbial community. The stabilization of a foam heterophase structure can be provided by various surfactants including those synthesized by living cells and products released during cell lysis. Such a foam system could harbor a microbial community of different species of (poly)extremophilic microorganisms that are capable of photo-and chemosynthesis and may be closely integrated into aero-geochemical processes including the processes of high-temperature polymer synthesis on the planet’s surface. Different complex nanostructures transferred to the cloud layers by convection flows could further contribute to the stabilization of heterophase liquid-gas foam structure and participate in chemical and photochemical reactions, thus supporting ecosystem stability. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

    Variability in methane emissions from West Siberia's shallow boreal lakes on a regional scale and its environmental controls

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    Small lakes represent an important source of atmospheric CH4 from northern wetlands. However, spatiotemporal variations in flux magnitudes and the lack of knowledge about their main environmental controls contribute large uncertainty into the global CH4 budget. In this study, we measured methane fluxes from small lakes using chambers and bubble traps. Field investigations were carried out in July–August 2014 within the West Siberian middle and southern taiga zones. The average and median of measured methane chamber fluxes were 0.32 and 0.30 mgCH4 m−2 h−1 for middle taiga lakes and 8.6 and 4.1 mgCH4 m−2 h−1 for southern taiga lakes, respectively. Pronounced flux variability was found during measurements on individual lakes, between individual lakes and between zones. To analyze these differences and the influences of environmental controls, we developed a new dynamic process-based model. It shows good performance with emission rates from the southern taiga lakes and poor performance for individual lakes in the middle taiga region. The model shows that, in addition to wellknown controls such as temperature, pH and lake depth, there are significant variations in the maximal methane production potential between these climatic zones. In addition, the model shows that variations in gas-filled pore space in lake sediments are capable of controlling the total methane emissions from individual lakes. The CH4 emissions exhibited distinct zonal differences not only in absolute values but also in their probability density functions: the middle taiga lake fluxes were best described by a lognormal distribution while the southern taiga lakes followed a power-law distribution. The latter suggests applicability of self-organized criticality theory for methane emissions from the southern taiga zone, which could help to explain the strong variability within individual lakes

    A coupled, pore-scale model for methanogenic microbial activity in underground hydrogen storage.

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    Underground hydrogen storage (UHS) as a means of energy storage is an efficient way of compensating for seasonal fluctuations in the availability of energy. One important factor which influences this technology is the activity of methanogenic microorganisms capable of utilising hydrogen and carbon dioxide for metabolism and leading to a change in the stored gas composition. A coupled, pore-scale model is presented which aids in the investigation of the mechanisms that govern the conversion of hydrogen to methane, i.e. advective hydrogen flow, its diffusion into microbial biofilms of multiple species, and its consumption within these biofilms. The model assumes that spherical grains are coated by a film of residual water and treats the biofilm development within each film in a quasi one-dimensional manner. A sample simulation using the presented model illustrates the biofilm growth process in these films as well as the competition between three different microbial species: methanogens, acetogens, and acetotrophs

    Aquatic export of young dissolved and gaseous carbon from a pristine boreal fen: Implications for peat carbon stock stability

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    The stability of northern peatland's carbon (C) store under changing climate is of major concern for the global C cycle. The aquatic export of C from boreal peatlands is recognized as both a critical pathway for the remobilization of peat C stocks as well as a major component of the net ecosystem C balance (NECB). Here, we present a full year characterization of radiocarbon content (14C) of dissolved organic carbon (DOC), carbon dioxide (CO2), and methane (CH4) exported from a boreal peatland catchment coupled with 14C characterization of the catchment's peat profile of the same C species. The age of aquatic C in runoff varied little throughout the year and appeared to be sustained by recently fixed C from the atmosphere (<60 years), despite stream DOC, CO2, and CH4 primarily being sourced from deep peat horizons (2–4 m) near the mire's outlet. In fact, the 14C content of DOC, CO2, and CH4 across the entire peat profile was considerably enriched with postbomb C compared with the solid peat material. Overall, our results demonstrate little to no mobilization of ancient C stocks from this boreal peatland and a relatively large resilience of the source of aquatic C export to forecasted hydroclimatic changes

    Complete genome sequence of the gliding, heparinolytic Pedobacter saltans type strain (113T)

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    Pedobacter saltans Steyn et al. 1998 is one of currently 32 species in the genus Pedobacter within the family Sphingobacteriaceae. The species is of interest for its isolated location in the tree of life. Like other members of the genus P. saltans is heparinolytic. Cells of P. saltans show a peculiar gliding, dancing motility and can be distinguished from other Pedobacter strains by their ability to utilize glycerol and the inability to assimilate D-cellobiose. The genome presented here is only the second completed genome sequence of a type strain from a member of the family Sphingobacteriaceae to be published. The 4,635,236 bp long genome with its 3,854 protein-coding and 67 RNA genes consists of one chromosome, and is a part of the Genomic Encyclopedia of Bacteria and Archaea project

    Exobiology of the Venusian Clouds: New Insights into Habitability through Terrestrial Models and Methods of Detection

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    The search for life beyond Earth has focused on Mars and the icy moons Europa and Enceladus, all of which are considered a safe haven for life due to evidence of current or past water. The surface of Venus, on the other hand, has extreme conditions that make it a nonhabitable environment to life as we know it. This is in contrast, however, to its cloud layer, which, while still an extreme environment, may prove to be a safe haven for some extreme forms of life similar to extremophiles on Earth. We consider the venusian clouds a habitable environment based on the presence of (1) a solvent for biochemical reactions, (2) appropriate physicochemical conditions, (3) available energy, and (4) biologically relevant elements. The diversity of extreme microbial ecosystems on Earth has allowed us to identify terrestrial chemolithoautotrophic microorganisms that may be analogs to putative venusian organisms. Here, we hypothesize and describe biological processes that may be performed by such organisms in the venusian clouds. To detect putative venusian organisms, we describe potential biosignature detection methods, which include metal-microbial interactions and optical methods. Finally, we describe currently available technology that can potentially be used for modeling and simulation experiments. © Copyright 2021, Mary Ann Liebert, Inc., publishers 2021.NASA HQ Planetary ScienceSpace Research Institute of the Russian Academy of SciencesUniversity of Wisconsin-Madison, UWAustrian Science Fund, FWF, (V333)The work presented here was motivated by fruitful dialogue at the 2019 Venus Cloud Layer Habitability and Landing Site Selection workshop organized by the Roscosmos-IKI/NASA Venera-D Joint Science Definition Team and supported by NASA HQ Planetary Science (A. Ocampo, Lead Venus Scientist) and Astrobiology programs (M. Voytek, Senior Scientist for Astrobiology) and the Space Research Institute of the Russian Academy of Sciences (IKI RAN). JAC acknowledges the support of the Genome Sciences Training Program at University of Wisconsin–Madison. TM is grateful to the Austrian Science Fund (FWF) for providing support through the Elise-Richter Research fellowship (V333). We thank Sanjay Limaye for his support, including of this publication, and for resparking the conversation on Venus astrobiology

    Complete genome sequence of the sulfur compounds oxidizing chemolithoautotroph Sulfuricurvum kujiense type strain (YK-1T)

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    Sulfuricurvum kujiense Kodama and Watanabe 2004 is the type species of the monotypic genus Sulfuricurvum, which belongs to the family Helicobacteraceae in the class Epsilonproteobacteria. The species is of interest because it is frequently found in crude oil and oil sands where it utilizes various reduced sulfur compounds such as elemental sulfur, sulfide and thiosulfate as electron donors. Members of the species do not utilize sugars, organic acids or hydrocarbons as carbon and energy sources. This genome sequence represents the type strain of the only species in the genus Sulfuricurvum. The genome, which consists of a circular chromosome of 2,574,824 bp length and four plasmids of 118,585 bp, 71,513 bp, 51,014 bp, and 3,421 bp length, respectively, harboring a total of 2,879 protein-coding and 61 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project

    Genome sequence and functional genomic analysis of the oil-degrading bacterium Oleispira antarctica

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    M.K. and P.N.G. designed the work; T.N.C. performed physiological studies; M.K., M.F., Y.A.-R., A.B., N.L.-C., M.E.G., O.R.K., T.Y.N., S.K., I.L., O.V.G., M.M.Y. R.R. and P.N.G. were associated with genome annotation; H.J.H. performed lipids and FAME analysis; M.F., M-l.F., S.J., S.C. and J.P.A performed chaperonin anti-proteome analysis; A.-x. S., O.K., O.E., P.A.P., P.S. and Y.K. were associated with structural proteomics; A.T. and R.F. were associated with functional proteomics; H.L. performed electron microscopy; R.D. performed real-time PCR; M.M.-G. and M.F. performed DIGE proteome analysis; M.G. was involved in siderophore production; O.N.R. performed genomic islands’ analysis; H.T. performed storage lipid compounds’ analysis; P.N.G. coordinated manuscript writing.Accession Codes: The genome sequence of Oleispira antarctica RB-8 has been deposited in GenBank under accession core FO203512. Protein structures have deposited in PDB under accession codes 3QVM (a/b hydrolase, OLEAN_C08020), 3QVQ (phosphodiesterase, OLEAN_C20330), 3M16 (transaldolase, OLEAN_C18160), 3LQY (isochorismatase, OLEAN_C07660), 3LNP (amidohydrolase, OLEAN_C13880), 3V77/3L53 (fumarylacetoacetate isomerase/hydrolase, OLEAN_C35840), 3VCR/3LAB (2-keto-3-deoxy-6-phosphogluconate aldolase, OLEAN_C25130), 3IRU (phoshonoacetaldehyde hydrolase, OLEAN_C33610), 3I4Q (inorganic pyrophosphatase, OLEAN_C30460), 3LMB (protein with unknown function, OLEAN_C10530).Ubiquitous bacteria from the genus Oleispira drive oil degradation in the largest environment on Earth, the cold and deep sea. Here we report the genome sequence of Oleispira antarctica and show that compared with Alcanivorax borkumensis—the paradigm of mesophilic hydrocarbonoclastic bacteria—O. antarctica has a larger genome that has witnessed massive gene-transfer events. We identify an array of alkane monooxygenases, osmoprotectants, siderophores and micronutrient-scavenging pathways. We also show that at low temperatures, the main protein-folding machine Cpn60 functions as a single heptameric barrel that uses larger proteins as substrates compared with the classical double-barrel structure observed at higher temperatures. With 11 protein crystal structures, we further report the largest set of structures from one psychrotolerant organism. The most common structural feature is an increased content of surface-exposed negatively charged residues compared to their mesophilic counterparts. Our findings are relevant in the context of microbial cold-adaptation mechanisms and the development of strategies for oil-spill mitigation in cold environments.We acknowledge the funding from the EU Framework Program 7 to support Projects MAMBA (226977), ULIXES (266473), MAGIC PAH (245226) and MICROB3 (287589) This work received the support of the Government of Canada through Genome Canada and the Ontario Genomics Institute (grant 2009-OGI-ABC-1405 to A.F.Y. and A.S.), and the U.S. Government National Institutes of Health (grants GM074942 and GM094585 (to A.S. through Midwest Center for Structural Genomics). The study was supported by the Max Planck Society and the Deutsche Forschungsgemeinschaft through project KU 2679/2-1 and BU 890/21-1. We thank the sequencing team of the AG Reinhardt for technical assistance and Alfred Beck for computational support. The skilful work of electron microscopic sample preparation by Mrs. Ingeborg Kristen (Dept. VAM, HZI Braunschweig) is gratefully acknowledged. Authors thank Professor Ken Timmis for his critical reading the manuscript and useful comments.http://www.nature.com/naturecommunicationsam201

    A concept for international societally relevant microbiology education and microbiology knowledge promulgation in society

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    Microbes are all pervasive in their distribution and influence on the functioning and well-being of humans, life in general and the planet. Microbially-based technologies contribute hugely to the supply of important goods and services we depend upon, such as the provision of food, medicines and clean water. They also offer mechanisms and strategies to mitigate and solve a wide range of problems and crises facing humanity at all levels, including those encapsulated in the sustainable development goals (SDGs) formulated by the United Nations. For example, microbial technologies can contribute in multiple ways to decarbonisation and hence confronting global warming, provide sanitation and clean water to the billions of people lacking them, improve soil fertility and hence food production and develop vaccines and other medicines to reduce and in some cases eliminate deadly infections. They are the foundation of biotechnology, an increasingly important and growing business sector and source of employment, and the centre of the bioeconomy, Green Deal, etc. But, because microbes are largely invisible, they are not familiar to most people, so opportunities they offer to effectively prevent and solve problems are often missed by decision-makers, with the negative consequences this entrains. To correct this lack of vital knowledge, the International Microbiology Literacy Initiative–the IMiLI–is recruiting from the global microbiology community and making freely available, teaching resources for a curriculum in societally relevant microbiology that can be used at all levels of learning. Its goal is the development of a society that is literate in relevant microbiology and, as a consequence, able to take full advantage of the potential of microbes and minimise the consequences of their negative activities. In addition to teaching about microbes, almost every lesson discusses the influence they have on sustainability and the SDGs and their ability to solve pressing problems of societal inequalities. The curriculum thus teaches about sustainability, societal needs and global citizenship. The lessons also reveal the impacts microbes and their activities have on our daily lives at the personal, family, community, national and global levels and their relevance for decisions at all levels. And, because effective, evidence-based decisions require not only relevant information but also critical and systems thinking, the resources also teach about these key generic aspects of deliberation. The IMiLI teaching resources are learner-centric, not academic microbiology-centric and deal with the microbiology of everyday issues. These span topics as diverse as owning and caring for a companion animal, the vast range of everyday foods that are produced via microbial processes, impressive geological formations created by microbes, childhood illnesses and how they are managed and how to reduce waste and pollution. They also leverage the exceptional excitement of exploration and discovery that typifies much progress in microbiology to capture the interest, inspire and motivate educators and learners alike. The IMiLI is establishing Regional Centres to translate the teaching resources into regional languages and adapt them to regional cultures, and to promote their use and assist educators employing them. Two of these are now operational. The Regional Centres constitute the interface between resource creators and educators–learners. As such, they will collect and analyse feedback from the end-users and transmit this to the resource creators so that teaching materials can be improved and refined, and new resources added in response to demand: educators and learners will thereby be directly involved in evolution of the teaching resources. The interactions between educators–learners and resource creators mediated by the Regional Centres will establish dynamic and synergistic relationships–a global societally relevant microbiology education ecosystem–in which creators also become learners, teaching resources are optimised and all players/stakeholders are empowered and their motivation increased. The IMiLI concept thus embraces the principle of teaching societally relevant microbiology embedded in the wider context of societal, biosphere and planetary needs, inequalities, the range of crises that confront us and the need for improved decisioning, which should ultimately lead to better citizenship and a humanity that is more sustainable and resilient. The biosphere of planet Earth is a microbial world: a vast reactor of countless microbially driven chemical transformations and energy transfers that push and pull many planetary geochemical processes, including the cycling of the elements of life, mitigate or amplify climate change (e.g., Nature Reviews Microbiology, 2019, 17, 569) and impact the well-being and activities of all organisms, including humans. Microbes are both our ancestors and creators of the planetary chemistry that allowed us to evolve (e.g., Life's engines: How microbes made earth habitable, 2023). To understand how the biosphere functions, how humans can influence its development and live more sustainably with the other organisms sharing it, we need to understand the microbes. In a recent editorial (Environmental Microbiology, 2019, 21, 1513), we advocated for improved microbiology literacy in society. Our concept of microbiology literacy is not based on knowledge of the academic subject of microbiology, with its multitude of component topics, plus the growing number of additional topics from other disciplines that become vitally important elements of current microbiology. Rather it is focused on microbial activities that impact us–individuals/communities/nations/the human world–and the biosphere and that are key to reaching informed decisions on a multitude of issues that regularly confront us, ranging from personal issues to crises of global importance. In other words, it is knowledge and understanding essential for adulthood and the transition to it, knowledge and understanding that must be acquired early in life in school. The 2019 Editorial marked the launch of the International Microbiology Literacy Initiative, the IMiLI. HERE, WE PRESENT our concept of how microbiology literacy may be achieved and the rationale underpinning it; the type of teaching resources being created to realise the concept and the framing of microbial activities treated in these resources in the context of sustainability, societal needs and responsibilities and decision-making; and the key role of Regional Centres that will translate the teaching resources into local languages, adapt them according to local cultural needs, interface with regional educators and develop and serve as hubs of microbiology literacy education networks. The topics featuring in teaching resources are learner-centric and have been selected for their inherent relevance, interest and ability to excite and engage. Importantly, the resources coherently integrate and emphasise the overarching issues of sustainability, stewardship and critical thinking and the pervasive interdependencies of processes. More broadly, the concept emphasises how the multifarious applications of microbial activities can be leveraged to promote human/animal, plant, environmental and planetary health, improve social equity, alleviate humanitarian deficits and causes of conflicts among peoples and increase understanding between peoples (Microbial Biotechnology, 2023, 16(6), 1091–1111). Importantly, although the primary target of the freely available (CC BY-NC 4.0) IMiLI teaching resources is schoolchildren and their educators, they and the teaching philosophy are intended for all ages, abilities and cultural spectra of learners worldwide: in university education, lifelong learning, curiosity-driven, web-based knowledge acquisition and public outreach. The IMiLI teaching resources aim to promote development of a global microbiology education ecosystem that democratises microbiology knowledge.http://www.wileyonlinelibrary.com/journal/mbt2hj2024BiochemistryGeneticsMicrobiology and Plant PathologySDG-01:No povertySDG-02:Zero HungerSDG-03:Good heatlh and well-beingSDG-04:Quality EducationSDG-06:Clean water and sanitationSDG-07:Affordable and clean energySDG-08:Decent work and economic growthSDG-12:Responsible consumption and productionSDG-13:Climate actionSDG-14:Life below wate
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