19 research outputs found
Cultivation With Powdered Meteorite (NWA 1172) as the Substrate Enhances Low-Temperature Preservation of the Extreme Thermoacidophile Metallosphaera sedula
Recent studies have uncovered a vast number of thermophilic species in icy environments, permanently cold ocean sediments, cold sea waters, and cool soils. The survival of thermophiles in psychrobiotic habitats requires thorough investigation of the physiological and molecular mechanisms behind their natural cryopreservation. Such investigations are mainly impeded due to a restricted cultivation of thermophiles at low temperatures under the laboratory conditions. Artificial culture media used under the laboratory conditions usually fail to support cultivation of thermophiles at low-temperature range. In this study we cultivated the extreme thermoacidophilic archaeonMetallosphaera sedulawith the preliminary powdered and sterilized multimetallic extraterrestrial mineral material (the meteorite NWA 1172) under a low temperature regime in laboratory conditions. Our data indicate thatM. sedulawithstands cold stress and can be maintained at low temperatures, when supplemented with the meteorite NWA 1172 as the sole energy source. Cultivation with the meteorite NWA 1172 opens up new, previously unknown psychrotolerant characteristics ofM. sedula, emphasizing that culture conditions (i.e., the "nutritional environment") may affect the microbial survival potential in stress related situations. These observations facilitate further investigation of strategies and underlying molecular mechanisms of the survival of thermophilic species in permanently cold habitats
Red-giant and main-sequence solar-like oscillators in binary systems revealed by ESA Gaia Data Release 3 -- Reconstructing stellar and orbital evolution from binary-star ensemble seismology
Binary systems constitute a valuable astrophysics tool for testing our
understanding of stellar structure and evolution. Systems containing a
oscillating component are interesting as asteroseismology offers independent
parameters for the oscillating component that aid the analysis. About 150 of
such systems are known in the literature. To enlarge the sample of these
benchmark objects, we crossmatch the Two-Body-Orbit Catalogue (TBO) of Gaia
DR3, with catalogs of confirmed solar-like oscillators on the main-sequence and
red-giant phase from NASA Kepler and TESS. We obtain 954 new binary system
candidates hosting solar-like oscillators, of which 45 and 909 stars are on the
main sequence and red-giant, resp., including 2 new red giants in eclipsing
systems. 918 oscillators in potentially long-periodic systems are reported. We
increase the sample size of known solar-like oscillators in binary systems by
an order of magnitude. We present the seismic properties of the full sample and
conclude that the grand majority of the orbital elements in the TBO is
physically reasonable. 82% of all TBO binary candidates with multiple times
with APOGEE are confirmed from radial-velocity measurement. However, we suggest
that due to instrumental noise of the TESS satellite the seismically inferred
masses and radii of stars with 30Hz could be
significantly overestimated. For 146 giants the seismically inferred
evolutionary state has been determined and shows clear differences in their
distribution in the orbital parameters, which are accounted the accumulative
effect of the equilibrium tide acting in these evolved binary systems. For
other 146 systems hosting oscillating stars values for the orbital inclination
were found in the TBO. From testing the TBO on the SB9 catalogue, we obtain a
completeness factor of 1/3.Comment: under review for publication in A&A (22 pages + 4 pages of appendix,
21 figures, 33 pages of tables in the Appendix
MiL-FISH: Multilabeled Oligonucleotides for Fluorescence In Situ Hybridization Improve Visualization of Bacterial Cells
Fluorescence in situ hybridization (FISH) has become a vital tool for environmental and medical microbiology and is commonly used for the identification, localization, and isolation of defined microbial taxa. However, fluorescence signal strength is often a limiting factor for targeting all members in a microbial community. Here, we present the application of a multilabeled FISH approach (MiL-FISH) that (i) enables the simultaneous targeting of up to seven microbial groups using combinatorial labeling of a single oligonucleotide probe, (ii) is applicable for the isolation of unfixed environmental microorganisms via fluorescence-activated cell sorting (FACS), and (iii) improves signal and imaging quality of tissue sections in acrylic resin for precise localization of individual microbial cells. We show the ability of MiL-FISH to distinguish between seven microbial groups using a mock community of marine organisms and its applicability for the localization of bacteria associated with animal tissue and their isolation from host tissues using FACS. To further increase the number of potential target organisms, a streamlined combinatorial labeling and spectral imaging-FISH (CLASI-FISH) concept with MiL-FISH probes is presented here. Through the combination of increased probe signal, the possibility of targeting hard-to-detect taxa and isolating these from an environmental sample, the identification and precise localization of microbiota in host tissues, and the simultaneous multilabeling of up to seven microbial groups, we show here that MiL-FISH is a multifaceted alternative to standard monolabeled FISH that can be used for a wide range of biological and medical applications
Endosymbionts escape dead hydrothermal vent tubeworms to enrich the free-living population
Theory predicts that horizontal acquisition of symbionts by plants and animals must be coupled to release and limited dispersal of symbionts for intergenerational persistence of mutualisms. For deep-sea hydrothermal vent tubeworms (Vestimentifera, Siboglinidae), it has been demonstrated that a few symbiotic bacteria infect aposymbiotic host larvae and grow in a newly formed organ, the trophosome. However, whether viable symbionts can be released to augment environmental populations has been doubtful, because (i) the adult worms lack obvious openings and (ii) the vast majority of symbionts has been regarded as terminally differentiated. Here we show experimentally that symbionts rapidly escape their hosts upon death and recruit to surfaces where they proliferate. Estimating symbiont release from our experiments taken together with well-known tubeworm density ranges, we suggest a few million to 1.5 billion symbionts seeding the environment upon death of a tubeworm clump. In situ observations show that such clumps have rapid turnover, suggesting that release of large numbers of symbionts may ensure effective dispersal to new sites followed by active larval colonization. Moreover, release of symbionts might enable adaptations that evolve within host individuals to spread within host populations and possibly to new environments
Multilabeled fluorescence in situ hybridization (MiL-FISH) oligonucleotides improve visualization of bacterial cells
Fluorescence in situ hybridisation (FISH) has become a vital tool for environmental and medical microbiology and is commonly used for the identification, localisation and isolation of defined microbial taxa. However, fluorescence signal strength is often a limiting factor for targeting all members in a microbial community. Here we present the application of a multi-labelled FISH approach (MiL-FISH) that: 1) enables the targeting of up to seven microbial groups simultaneously using multi-spectral labelling of a single oligonucleotide probe, 2) is applicable for the isolation of unfixed environmental microorganisms via fluorescence activated cell sorting (FACS), and 3) improves signal and imaging quality of tissue sections in acrylic resin for precise localisation of individual microbial cells. We show the ability of MiL-FISH to distinguish between seven microbial groups using a mock community of marine organisms, and its applicability for the localisation of bacteria associated with animal tissue as well as their isolation from host tissues using FACS. To further increase the number of potential target organisms a streamlined “combinatorial labelling and spectral imaging-FISH (CLASI-FISH)” concept with MiL-FISH probes is presented. Through the combination of increased probe signal, the possibility to target hard-to-detect taxa and isolate these from an environmental sample, the identification and precise localisation of microbiota in host tissues and the simultaneous multi-labelling of up to seven microbial groups, we show here that MiL-FISH is a multi-faceted alternative to standard mono-labelled FISH that can be used for a wide range of biological and medical applications
ENSURE - Integration of Volunteers in Disaster Management
Part 5: Risk and Disaster ManagementInternational audienceVolunteers can be a valuable support for disaster management. Disaster management must be able to coordinate volunteers in order to benefit from their support. Interactive, collaborative, and mobile technologies have the potential to overcome the challenges involved in integrating volunteers into crisis and disaster management. This paper presents the ENSURE system, designed to effectively integrate volunteers for an improved approach to disaster management. The system supports the aid forces in recruiting, managing, activating, and coordinating volunteers in the event of a large-scale emergency. To achieve this, ENSURE provides necessary functions such as volunteer registration, volunteer profiles, sending alerts, and volunteer activation (via the mobile app). The system uses a subscription-based approach in which the volunteers agree to take part in an emergency operation by responding to an alert. The system architecture provides technical insights into how to implement crowdtasking systems. It contains seven logical components to provide the necessary features. It was designed to ensure scalability, performance, and availability. The results of a first comprehensive evaluation of ENSURE, which was performed as a large-scale exercise directed by the disaster relief forces in Berlin, were, without exception, positive in all three evaluation areas: efficiency & security, clarity & usability, reliability & availability
A specific and widespread association between deep-sea Bathymodiolus mussels and a novel family of Epsilonproteobacteria
Bathymodiolus mussels dominate animal communities at many hydrothermal vents and cold seeps. Essential to the mussels' ecological and evolutionary success is their association with symbiotic methaneand sulfur-oxidizing gammaproteobacteria, which provide them with nutrition. In addition to these wellknown gammaproteobacterial endosymbionts, we found epsilonproteobacterial sequences in metatranscriptomes, metagenomes and 16S rRNA clone libraries as well as by polymerase chain reaction screening of Bathymodiolus species sampled from vents and seeps around the world. These epsilonproteobacterial sequences were closely related, indicating that the association is highly specific. The Bathymodiolus-associated epsilonproteobacterial 16S rRNA sequences were at most 87.6% identical to the closest cultured relative, and 91.2% identical to the closest sequences in public databases. This clade therefore represents a novel family within the Epsilonproteobacteria. Fluorescence in situ hybridization and transmission electron microscopy showed that the bacteria are filamentous epibionts associated with the gill epithelia in two Bathymodiolus species. In animals that host highly specific symbioses with one or a few types of endosymbionts, other lessabundant members of the microbiota can be easily overlooked. Our work highlights how widespread and specific associations with less-abundant microbes can be. Possibly, these microbes play an important role in the survival and health of their animal hosts
An Architecture for the Semantic Enhancement of Environmental Resources
Part 4: Semantics and EnvironmentInternational audienceThe vision of a Single Information Space in Europe for the Environment (SISE) requires seamless access to environmental resources, including data, models and services. Standardization organizations like OGC and OASIS have laid the foundations for interoperability on a syntactic level for many aspects of distributed environmental information systems (e.g. OGC SWE for sensor information). At the same time, the EC has undertaken a considerable effort to commit European stakeholders to offering their environmental information in such a way that it is accessible by interested parties, both on the scientific level by supporting research projects, like ORCHESTRA and SANY, and on the legal level by introducing directives (such as the INSPIRE directive). This development, amongst others, has led to the present situation in which a large number of environmental information sources are available. However, to implement the vision of the SISE it is not enough to publish resources. Environmental information must be discoverable, and it must be ‘understandable’ in different contexts in order to be used effectively by parties of various thematic domains. Therefore, in order to foster the implementation of SISE, semantic interoperability is a necessary element. Key to semantic interoperability is the presence of meta-information which describes the concepts of the environmental resources. Producing this meta-information puts a heavy technological burden on the individual resource providers such that it seems unlikely that enough semantic meta-information will ever be made available to reach semantic interoperability and thus accomplish the vision of SISE unless other ways to provide this essential meta-information are found. In this paper we introduce an architecture, developed in the FP7 project TaToo (247893), which tries to overcome the aforementioned obstacles by providing the possibility to easily annotate and rate environmental information resources, even by parties which do not own the resource, and transparently equipping this information with domain knowledge and thus enhancing discoverability and usability of resources with semantic technologies. The objective of the architecture is to seamlessly blend in with existing infrastructures by making use of de facto standards while offering support for discovery, annotation and validation of environmental resources through open interfaces
Exploring the microbial biotransformation of extraterrestrial material on nanometer scale
Exploration of microbial-meteorite redox interactions highlights the possibility of bioprocessing of extraterrestrial metal resources and reveals specific microbial fingerprints left on extraterrestrial material. In the present study, we provide our observations on a microbial-meteorite nanoscale interface of the metal respiring thermoacidophile Metallosphaera sedula. M. sedula colonizes the stony meteorite Northwest Africa 1172 (NWA 1172; an H5 ordinary chondrite) and releases free soluble metals, with Ni ions as the most solubilized. We show the redox route of Ni ions, originating from the metallic Ni2+ of the meteorite grains and leading to released soluble Ni2+. Nanoscale resolution ultrastructural studies of meteorite grown M. sedula coupled to electron energy loss spectroscopy (EELS) points to the redox processing of Fe-bearing meteorite material. Our investigations validate the ability of M. sedula to perform the biotransformation of meteorite minerals, unravel microbial fingerprints left on meteorite material, and provide the next step towards an understanding of meteorite biogeochemistry. Our findings will serve in defining mineralogical and morphological criteria for the identification of metal-containing microfossils