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Our ability to explore the cosmos by direct contact has been limited to a small number of lunar and interplanetary missions. However, the NASA Starlight program points a path forward to send small, relativistic spacecraft far outside our solar system via standoff directed-energy propulsion. These miniaturized spacecraft are capable of robotic exploration but can also transport seeds and organisms, marking a profound change in our ability to both characterize and expand the reach of known life. Here we explore the biological and technological challenges of interstellar space biology, focusing on radiation-tolerant microorganisms capable of cryptobiosis. Additionally, we discuss planetary protection concerns and other ethical considerations of sending life to the stars. • NASA Starlight program details a path to send small relativistic spacecraft to interstellar space. • Relativistic spacecraft can transport seeds and live organisms to characterize and expand life. • Biological and technological challenges of interstellar space biology are outlined. • Guidelines for species selection based on research practicality and survivability are offered. • Current planetary protection regulations cannot address ethics of extrasolar biology missions. [ABSTRACT FROM AUTHOR]

Developing tumor-specific drug delivery systems with minimized off-target cargo leakage remains an enduring challenge. In this study, inspired from the natural cryptobiosis explored by certain organisms and stimuli-responsive polyphenol‒metal coordination chemistry, doxorubicin (DOX)-conjugated gelatin nanoparticles with protective shells formed by complex of tannic acid and FeIII (DG@TA-FeIII NPs) were successfully developed as an "AND" logic gate platform for tumor-targeted DOX delivery. Moreover, benefiting from the well-reported photothermal conversion ability of TA-FeIII complex, a synergistic tumor inhibition effect was confirmed by treating 4T1 tumor-bearing mice with DG@TA-FeIII NPs and localized near-infrared (NIR) laser irradiation. As a proof of concept study, this work present a simple strategy for developing "AND" logic gate platforms by coating enzyme-degradable drug conjugates with detachable polyphenol‒metal shells. An "AND" logic gate platform for controlled drug delivery was successfully developed by coating enzyme-degradable drug conjugates with detachable polyphenol-metal shells to mimic natural cryptobiosis. Image 1 [ABSTRACT FROM AUTHOR]

To examine physiological adaptations to the two combined stressors O 2 deprivation and extreme CO 2 concentrations, we compared respiratory responses of two nematode species occurring in natural CO 2 springs. The minimum O 2 concentration allowing maintenance of respiration in both species was 0.0176 μmol O 2 ml −1 (corresponds to 1.4% O 2 in air). After exposure to anoxia, individuals resumed respiration immediately when O 2 was added, but on a lower level compared to control and without showing a respiratory overshoot. A species-specific response was found in respiration rate during 20% CO 2 : the more tolerant species maintained respiration rates, whereas the sensitive species showed a decreased respiration rate as low as after anoxia. The results indicate that during 20% CO 2 the sensitive species undergo a survival state. We conclude, that the ability to maintain respiration even under low oxygen and high CO 2 concentrations may allow the better adapted species to occupy an ecological niche in the field, where others cannot exist. [ABSTRACT FROM AUTHOR]

Resurrection plants are able to tolerate the extreme desiccation of their vegetative tissues and after the increase of water availability recover their full metabolic capacity. This capacity that depends on the regulatory mechanisms that allow metabolism occurs under low water potential until the anabiosis state. The responses to the desiccation process in Barbacenia purpurea (Velloziaceae), a resurrection plant commonly found in rock outcrops in Rio de Janeiro, Brazil, start when leaf water relative content decreases below 70%. In this work, we studied the influence of total water withholding on physiological and metabolic parameters during desiccation of B. purpurea under winter and summer conditions. Throughout the desiccation process of B. purpurea , morphological alterations such as subtle leaf curling and osmotic adjustment were observed in both winter and summer seasons. Increased uronic acid content in the leaf cell walls also occurred in response to water suppression in both seasons. Despite some fluctuations, no significant differences in antioxidant activity during dehydration/rehydration were observed. Our findings indicate that the mechanisms implicated in desiccation tolerance in this species are governed by leaf water status and that the intensity of physiological and metabolic responses is modulated by seasonality due to the amplitude of the environmental changes in each season. [ABSTRACT FROM AUTHOR]

For some years now, interactions between societies and the biosphere have been the subject of socio-ecological studies (SESs), which analyse socio-ecological regimes, trajectories and transitions. This article follows the approach, and seeks to contribute to the analysis of socio-ecological urban trajectories since the Industrial Revolution. It draws on some key notions which are tested and applied to Paris. The urban socio-ecological regime of the industrial era has three major characteristics: i) the near-total externalisation of a more intensive urban metabolism, associated with the breakup of supply areas and the deepening, urban footprint on the environment; ii) the importance of infrastructure to this metabolism, which fits into a process of generalised networking led by engineers and leads to urban technical inter-dependencies; and iii) the urbanisation of landscapes associated with the proliferation of extra-territorial urban influences, despite the loss of certain skills available to the French capital. [ABSTRACT FROM AUTHOR]

This study focuses on the CO2-tolerance of soil nematodes from natural CO2 springs (mofette fields). In laboratory experiments, we compared survival, reproduction, activity and reactivation of a CO2-sensitive species with a CO2-tolerant species. Both species survived even 100% CO2, but in an inactive state. The higher the CO2 concentration the more individuals entered inactivity. We found significant differences between the two species: more adults of the CO2-tolerant species maintained activity and reproduction at higher CO2 concentrations. Moreover, reactivation after inactivity was faster. Together with a higher juvenile mortality of the CO2-sensitive species, these interspecific differences are conclusive to explain the niche separation of the two species that was observed in the mofette field. [ABSTRACT FROM AUTHOR]

Abstract: While C2H2 zinc finger transcription factors (TF) are often regulated by abiotic stress, their role during insect infestation has been overlooked. This study demonstrates that the transcripts of the zinc finger transcription factors StZFP1 and StZFP2 are induced in potato (Solanum tuberosum L.) upon infestation by either the generalist tobacco hornworm (THW, Manduca sexta L.) or the specialist Colorado potato beetle (CPB, Leptinotarsa decemlineata Say). StZFP1 has been previously characterized as conferring salt tolerance to transgenic tobacco and its transcript is induced by Phytophthora infestans and several abiotic stresses. StZFP2 has not been characterized previously, but contains the hallmarks of a C2H2 zinc finger TF, with two conserved zinc finger domains and DLN motif, which encodes a transcriptional repressor domain. Expression studies demonstrate that StZFP2 transcript is also induced by tobacco hornworm and Colorado potato beetle. These observations expand the role of the C2H2 transcription factor in potato to include the response to chewing insect pests. [Copyright &y& Elsevier]

Abstract: Various abiotic stresses downgrade the quality and productivity of chrysanthemum. A construct carrying both CcSOS1 (from Chrysanthemum crassum) and CdICE1 (from Chrysanthemum dichrum) was constitutively expressed in the chrysanthemum variety ‘Jinba’. The transgenic plants were superior to the wild type (WT) ones with respect to their sensitivity to low temperature, drought and salinity, as measured by visible damage and plant survival. Salinity stressed transgenic plants accumulated more proline, and their level of superoxide dismutase and peroxidase activity was higher than in WT plants. At the physiological level, they suffered less loss of viable leaf area, maintained a lower leaf electrolyte conductivity and retained more chlorophyll (a+b). The ratio between the K+ and Na+ content was higher in the root, stem and median leaves of salinity stressed transgenic plants than in those of WT plants. [Copyright &y& Elsevier]

Highlights: [•] Breeding of pathogen-resistant fish is a viable option. [•] Innate immunity is via the Alternative Pathway of Complement Activation. [•] Recovered fish are protected from homologous challenge. [•] Two vaccines have been developed against cryptobiosis. [•] Vaccination against trypanosomiasis is a possibility. [Copyright &y& Elsevier]

Terrestrial microinvertebrates in Antarctica are potentially exposed to contaminants due to the concentration of human activity on ice-free areas of the continent. As such, knowledge of the response of Antarctic microinvertebrates to contaminants is important to determine the extent of anthropogenic impacts. Antarctic Philodina sp. were extracted from soils and mosses at Casey station, East Antarctica and exposed to aqueous Cu for 96 h. The Philodina sp. was sensitive to excess Cu, with concentrations of 36 μg L−1 Cu (48 h) and 24 μg L−1 Cu (96 h) inhibiting activity by 50%. This is the first study to be published describing the ecotoxicologically derived sensitivity of a rotifer from a terrestrial population to metals, and an Antarctic rotifer to contaminants. It is also the first study to utilise bdelloid rotifer cryptobiosis (chemobiosis) as a sublethal ecotoxicological endpoint. This preliminary investigation highlights the need for further research into the responses of terrestrial Antarctic microinvertebrates to contaminants. [Display omitted] • First investigation of the sensitivity of a terrestrial population of Antarctic rotifers to Cu. • The 96 h EC 50 for copper for Philodina sp. was 24 μg Cu L−1. • Chemobiosis provided a novel and useful behavioural endpoint. • This research will assist in developing Antarctic specific soil quality guidelines. [ABSTRACT FROM AUTHOR]

Abstract: The seasonality and unpredictability of environmental conditions at high altitudes and latitudes govern the life cycle patterns of organisms, giving rise to stresses that cause death or development of specific adaptations. Ice formation is a major variable affecting the survival of both freshwater fauna and fauna inhabiting lichens, mosses and leaf litter. Tardigrades occupy a wide range of niches in marine, freshwater and terrestrial environments. The highest number of species is found in terrestrial habitats thanks to their ability to enter anhydrobiosis and cryobiosis. The cryobiotic ability of tardigrade species from polar regions is well known. Consequently, we focused our research on the ability to survive freezing in the active hydrated state using seven tardigrade species differing in phylogenetic position and collected at various altitudes and from different habitats in a temperate area. Specimens were cooled at different cooling rates (from 0.31°Cmin−1 to 3.26°Cmin−1). Even though the final survival and the time required by animals to recover to active life were both inversely related to the cooling rate, highly significant interspecific differences were found. Species survival ability ranged from excellent to none. Species living in xeric habitats withstood freezing better than those living in hygrophilous habitats, while true limnic species did not exhibit any cryobiotic ability. The ability to withstand freezing seems linked to the anhydrobiotic ability. The differences in cryptobiotic performance among tardigrade species seem more influenced by selective pressures linked to local adaptation to habitat characteristics than by phylogenetic relationships. [Copyright &y& Elsevier]

Abstract: The perceived relative position of a moving object is frequently shifted as compared to the relative position of the object in the real world. The illusions have traditionally been explained by temporal models that influence the perceptual latency of visual objects. However, another compelling theory has recently been proposed on the basis of spatial models that directly influence the coded location of visual objects. In this study, spatial models were further supported by three different types of illusions composed of apparent motions, in which the perceived relative positions of stationary but apparently moving objects were shifted. One of three illusions was developed as a novel type of illusion in this paper (kebab illusion). The relative position shift of a stationary object suggested that spatial models play important roles on assignment of position of moving object as well as temporal models. A mechanism that integrated temporal and spatial models is also discussed. [Copyright &y& Elsevier]

The phytoalexin resveratrol (RESV), a defensive substance produced by plants in response to infection by pathogenic microorganisms, displays a wide range of biological effects in mammalian cells. In the present study, we analysed the in vitro effect of RESV on the amphizoic ciliate Philasterides dicentrarchi and demonstrated for the first time that this polyphenol causes cellular and metabolic abnormalities that generate an autophagic process and a state similar to cryptobiosis in the ciliate. At concentrations between 50 and 100μM, RESV had a cytocidal effect when the ciliate was grown in medium with low levels of nutrients, and a cytostatic effect when the parasite was grown in culture media rich in nutrients. At these concentrations, RESV induced alterations in mitochondria, generated autophagy, provoked a reduction in the cell volume, and also drastically reduced the ciliate endocytic activity in small ciliates, generating a state compatible with cryptobiosis. The results demonstrate that RESV is a potent inducer of autophagy in the scuticociliate P. dicentrarchi. The ciliate may therefore be a good experimental organism for identifying autophagy-inducing drugs with therapeutic potential in diseases in which autophagy plays a protective role. [Copyright &y& Elsevier]

Abstract: Certain organisms found across a range of taxa, including bacteria, yeasts, plants and many invertebrates such as nematodes and tardigrades are able to survive almost complete loss of body water. The dry organisms may remain in this state, which is known as anhydrobiosis, for decades without apparent damage. When water again becomes available, they rapidly rehydrate and resume active life. Research in anhydrobiosis has focused mainly on sugar metabolism and stress proteins. Despite the discovery of various molecules which are involved in desiccation and water stress, knowledge of the regulatory network governing the stability of the cellular architecture and the metabolic machinery during dehydration is still fragmentary and not well understood. A combination of transcriptional, proteomic and metabolic approaches with bioinformatics tools can provide a better understanding of gene regulation that underlie the biological functions and physiology related to anhydrobiosis. The development of this concept will raise exciting possibilities and techniques for the preservation and stabilization of biological materials in the dry state. [Copyright &y& Elsevier]

Tardigrades are renowned for their extreme stress tolerance, which includes the ability to endure complete desiccation, high levels of radiation and very low sub-zero temperatures. Nevertheless, tardigrades appear to be vulnerable to high temperatures and thus the potential effects of global warming. Here, we provide the first analysis of transcriptome data obtained from heat stressed specimens of the eutardigrade Ramazzottius varieornatus , with the aim of providing new insights into the molecular processes affected by high temperatures. Specifically, we compare RNA-seq datasets obtained from active, heat-exposed (35 °C) tardigrades to that of active controls kept at 5 °C. Our data reveal a surprising shift in transcription, involving 9634 differentially expressed transcripts, corresponding to >35% of the transcriptome. The latter data are in striking contrast to the hitherto observed constitutive expression underlying tardigrade extreme stress tolerance and entrance into the latent state of life, known as cryptobiosis. Thus, when examining the molecular response, heat-stress appears to be more stressful for R. varieornatus than extreme conditions, such as desiccation or freezing. A gene ontology analysis reveals that the heat stress response involves a change in transcription and presumably translation, including an adjustment of metabolism, and, putatively, preparation for encystment and subsequent diapause. Among the differentially expressed transcripts we find heat-shock proteins as well as the eutardigrade specific proteins (CAHS, SAHS, MAHS, RvLEAM, and Dsup). The latter proteins thus seem to contribute to a general stress response, and may not be directly related to cryptobiosis. [Display omitted] • For the tardigrade Ramazzottius varieornatus , 35 °C is appreciably more stressful than −80 °C. • Heat stress induces major shift in transcription involving >35% of transcriptome. • Tardigrade specific genes are differentially expressed following heat stress. • Heat stress response may putatively involve preparation for encystment and diapause. [ABSTRACT FROM AUTHOR]

This paper reports on the development and testing of two techniques for nebulizing cell solutions into aerosols that contain living cells in nanoliter droplets: one pneumatic technique and one ultrasonic technique. NIH 3T3 fibroblasts were tested for viability and the ability to attach and grow post-spraying. Viabilities for the two techniques ranged from 50 to 70% and virtually all cells that maintained membrane integrity post-spraying were able to attach and divide. The cellular aerosols were used to study the effect of drying rates and drying temperature on the post-rehydration survival of fibroblasts that were loaded with trehalose. Nanoliter droplets were developed for this study so that non-uniformities in moisture content and temperature within the samples would be minimized, and thus the drying rates experienced by the cells could be inferred. The main findings of this study are that the relative humidity of the drying environment does have a strong effect on the post-rehydration viability of desiccated cells, but that effect is entirely explained by differences in the residual moisture content experienced by the cells dried at different humidities. The post-rehydration viability of the cells was found to be dependent only on the residual moisture content achieved during drying and on whether or not trehalose was loaded inside the cell, and was not dependent on the drying rate or on the temperature at which drying occurred. A comparison of viabilities for cells dried in nanoliter droplets and cells dried in more commonly used 10 μL drops suggested that cells in larger drops were not experiencing the average water content for the drop as a whole during critical phases of the drying process. The apparent non-uniformity of moisture inside larger drops may contribute to difficulties in understanding and establishing successful long-term storage techniques in a dried state. [ABSTRACT FROM AUTHOR]

Abstract: A partially benzylated derivative of anhydro-d-altro-heptulose found in Coriaria japonica A, which is a synthetically useful unit, was successfully synthesized from a d-mannose derivative by a novel synthetic approach involving the intramolecular O-ketopyranosylation reaction developed by us. This synthetic approach was also applicable to the preparation of its four analogs. [Copyright &y& Elsevier]

Abstract: Diapause hormone (DH) effectively terminated pupal diapause in Helicoverpa zea. This effect was temperature-dependent, with an optimum of 21°C. The dose–response curve indicated an ED50 of DH for diapause termination of approximately 100pmol. The core sequence and essential amino acids were determined by bioassays using modified and truncated DH analogs. A C-terminal hepta-peptide, LWFGPRLa, was the core sequence required for diapause termination. Activity was lost when Alanine was substituted for any of the amino acids in the hepta-peptide, with the exception of Glycine. A fragment series of analogs suggested that the amide and Arginine were the most important components needed for terminating diapause. Leucine, Tryptophan, and Phenylalanine at the N-terminus of the hepta-peptide were also critical for activity. The C-terminal Leucine was less important: deletion resulted in decreased activity, although it could not be substituted by Alanine. The fact that a portion of the DH sequence is similar to the pyrokinin that accelerates fly pupariation prompted us to also evaluate the capability of DH to accelerate development in the flesh fly, Sarcophaga bullata. The threshold dose of DH essential to accelerate fly pupariation was 5pmol for immobilization/retraction and longitudinal contraction and 10pmol for tanning, approximately one or two orders of magnitude lower than the effective dose required for diapause termination in H. zea. Tensiometric measurements revealed that DH affected neuromuscular patterns of pupariation behavior and associated cuticular changes in a manner similar to that of the fly pyrokinins and their analogs. [Copyright &y& Elsevier]

Abstract: This study was carried out to investigate a role of the juvenile hormone analog, fenoxycarb (FC) in terminating the reproductive diapause in the black rice bug, Scotinophara lurida (Burmeister) (Heteroptera: Pentatomidae). FC-treated adults collected at different dates developed their ovaries sooner than untreated ones. Topical application of FC accelerated diapause termination of field-collected S. lurida in which FC-treated adults exhibited early oviposition. In FC-treated males, development of their accessory glands and testes accelerated appeared to be prompted. These results suggest that various physiological overwintering traits related to diapause in this species may in part be under gonadotrophic endocrine control. [Copyright &y& Elsevier]

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Abstract: Detailed studies have been undertaken on in situ spores of the Rhynie chert plant Aglaophyton (Rhynia) major (Kidston and Lang) D.S. Edwards. The in situ spores exhibit a variety of preservational types that are described. In several specimens, spores are exceptionally preserved: some apparently preserve an outer, enveloping, callose wall and others preserve the plasma membrane and possibly also cell contents. The in situ spores are relatively simple trilete spores with retusoid structure that are entirely laevigate and have a distinctive thinning associated with the trilete mark. They may be accommodated in the dispersed spore genus Retusotriletes. Identical spores occur dispersed in litter/soil horizons preserved in the chert (as individual spores, including germinating spores, in spore masses and in coprolites), and are also a common element of dispersed spore assemblages from throughout the stratigraphical sequence of the Rhynie outlier. The dispersed forms are placed with Retusotriletes sp. CW-A, as described by Wellman [Wellman, 2004. Palaeoecology and palaeophytogeography of the Rhynie chert plants: evidence from integrated analysis of in situ and dispersed spores. Proc. R. Soc. London, Ser. B 271, 985–992; Wellman, in press. Spore assemblages from the “Lower Old Red Sandstone” deposits of the Rhynie Outlier, Scotland. Trans. R. Soc. Edinburgh: Earth Sci.], and it is concluded that the dispersed spore taxon Retusotriletes sp. CW-A was produced by A. major. Integrated evidence from dispersed and in situ spores (particularly those exceptionally preserved) permits a detailed reconsideration of the many lines of evidence pertaining to the reproductive biology and ecology of the plant A. major. [Copyright &y& Elsevier]

Abstract: The tardigrade is a microscopic creature that under environmental stress conditions undergoes cryptobiosis [Feofilova, E.P., 2003. Deceleration of vital activity as a universal biochemical mechanism ensuring adaptation of microorganisms to stress factors: A review. Appl. Biochem. Microbiol. 39, 1–18; Nelson, D.R., 2002. Current status of the tardigrada: Evolution and ecology. Integrative Comp. Biol. 42, 652–659]—a temporary metabolic depression—which is considered to be a third state between life and death [Clegg, J.S., 2001. Cryptobiosis—a peculiar state of biological organization. Comp. Biochem. Physiol. Part B 128, 613–624]. In contrast with death, cryptobiosis is a reversible state, and as soon as environmental conditions change, the tardigrade “returns to life.” Cryptobiosis in general, and among the tardigrade in particular, is a phenomenon poorly understood [Guppy, M., 2004. The biochemistry of metabolic depression: a history of perceptions. Comp. Biochem. Physiol. Part B 139, 435–442; Schill, R.O., et al., 2004. Stress gene (hsp70) sequences and quantitative expression in Milensium tardigradum (Tardigrade) during active and cryptobiotic stages. J. Exp. Biol. 207, 1607–1613; Watanabe, M., et al., 2002. Mechanisn allowing an insect to survive complete dehydration and extreme temperatures. J. Exp. Biol. 205, 2799–2802; Wright, J.C., 2001. Cryptobiosis 300 years on from van Leuwenhoek: what have we learned about tardigrades? Zool. Anz. 240, 563–582]. Moreover, the ability of the tardigrade to bootstrap itself and to return to life seems paradoxical like the legendary Baron von Munchausen who pulled himself out of the swamp by grabbing his own hair. Two theoretical obstacles prevent us from advancing our knowledge of cryptobiosis. First, we lack appropriate theoretical understanding of reversible processes of biological computation in living systems. Second, we lack appropriate theoretical understanding of bootstrapping in living systems. In this short opinion article, I would like to present the idea that although cryptobiosis is obscure from a certain point of view, it makes sense within a scientific perspective suggesting that “organization becomes cause in the matter” [Strohman, R.C., 2000. Organization becomes cause in the matter. Nat. Biotechnol. 18, 575–576]. I present Bateson''s idea that organisms have a “recursive hierarchical” form of organization [Neuman, Y., 2004. Meaning making in the immune system. Perspect. Biol. Med. 48, 320–327; Neuman, Y., in press. A theory of meaning. Inform. Sci.] and suggest that this form of organization allows bootstrapping through reversible process of computation as discussed by theoretical physicists [Bennett, C.H., 1982. The thermodynamics of computation—a review. Int. J. Theoret. Phys. 1, 905–940; Landauer and Bennett, 1985]. [Copyright &y& Elsevier]

Abstract: Successful missions to Mars, Europe and other bodies of the Solar system have created a prerequisite to search for extraterrestrial life. The first attempts of microbial life detection on the Martian surface by the Viking landed missions gave no biological results. Microbiological investigations of the Martian subsurface ground ice layers seem to be more promising. It is well substantiated to consider the Antarctic ice sheet and the Antarctic and Arctic permafrost as terrestrial analogues of Martian habitats. The results of our long-standing microbiological studies of the Antarctic ice would provide the basis for detection of viable microbial cells on Mars. Our microbiological investigations of the deepest and thus most ancient strata of the Antarctic ice sheet for the first time gave evidence for the natural phenomenon of long-term anabiosis (preservation of viability and vitality for millennia years). A combination of classical microbiological methods, epifluorescence microscopy, SEM, TEM, molecular diagnostics, radioisotope labeling and other techniques made it possible for us to obtain convincing proof of the presence of pro- and eukaryotes in the Antarctic ice sheet. In this communication, we will review and discuss some critical issues related to the detection of viable microorganisms in cold terrestrial environments with regard to future searches for microbial life and/or its biological signatures on extraterrestrial objects. [Copyright &y& Elsevier]

Abstract: Peculiarities of the structural organization in non-spore-forming bacteria associated with long-term anabiosis were revealed both in laboratory cultures and in natural populations isolated from 1–3-Myr-old Eastern Siberian permafrost and tundra soil. Different advanced methods were used, including (a) high-resolution electron microscopy; (b) simulation of in situ conditions in the laboratory by varying the composition of growth medium and cultivation conditions; (c) low-temperature fractionation to isolate and concentrate microbial cells from natural soils; (d) comparative morphological analysis of microbial cells in model cultures and natural soils (in situ). Under laboratory conditions, the intense formation of resting cells by representatives of various taxa of eubacteria and halophilic archaea occurred in 2–9-month-old cultures grown in carbon-, nitrogen-, or phosphorus-limited media, in starved cell suspensions in the presence of sodium silicate, or on soil agar. Among resting cells, we revealed cystlike forms having a complicated structure and common features. These included a thick capsule; a thickened and multiprofile cell wall; the presence of large intramembrane particles on PF- and EF-fracture surfaces; fine-grained or lumpy cytoplasm; and a condensed nucleoid. The general morphological properties, ultrastructural organization, physiological features of cystlike cells, and their ability to germinate under the appropriate conditions suggest the existence of constitutive dormancy in non-spore-forming bacteria. It was found that the majority of microorganisms in permafrost and tundra soil are cystlike cells, very similar to those in laboratory cultures. Anabiotic (resting) cystlike cells are responsible for the survival of non-spore-formers in extreme Earth habitats and may be regarded as possible analogs of extraterrestrial forms of microbial life. [Copyright &y& Elsevier]

Abstract: Microorganisms were isolated from lignite freshly excavated in the Záhorie coal mine (southwestern Slovakia) under conditions excluding contamination with either soil or air-borne microorganisms. The isolates represented both Prokarya and Eukarya (fungi). All were able to grow on standard media, although some microorganisms were unstable and became extinct during storage of coal samples. Bacteria belonged to the genera Bacillus, Staphylococcus, and Rhodococcus, according to both morphological criteria and ITS sequences. Several bacterial isolates were resistant to antibiotics. The presence of anaerobic bacteria was also documented, although they have not yet been identified. Fungal isolates were typified by using their ITS sequences. They belonged to the genera Trichoderma (Hypocrea), Penicillium, Epicoccum, Metarhizium (Cordyceps), and Cladosporium. Several fungi produced compounds with antibiotic action against standard bacterial strains. The evidence for the presence of microorganisms in native lignite was obtained by means of fluorescence microscopy, scanning electron microscopy, and electron microprobe analysis. Results demonstrated that microorganisms were able to survive in the low-rank coal over a long time period. [Copyright &y& Elsevier]

Abstract: The larva of the African chironomid Polypedilum vanderplanki can withstand complete desiccation. Our previous reports revealed that even when the larva is dehydrated without a brain, it accumulated a great amount of trehalose and successfully went into anhydrobiosis. In this paper we determined the viability after rehydration in tissues from the larvae followed by complete dehydration. Only fat-body tissues that were the main producer of trehalose could be preserved in a dry state at room temperature for an extended period of more than 18 months in a viable form. Thus we have confirmed that the central nervous system is not involved in the induction of anhydrobiosis, even in this complex multicellular organism. [Copyright &y& Elsevier]

Abstract: In response to drought bdelloid and monogonont rotifers undergo anhydrobiosis and are assumed to synthesize protective chemicals, which are commonly sugars. In contrast to most anhydrobionts, bdelloids have earlier been shown to lack trehalose as protective chemical, and more importantly to lack trehalose synthase (tps) genes. It remains to be assessed if the absence of trehalose is a characteristic common to the entire taxon Rotifera, or if it is limited to bdelloids, or is peculiar to the two bdelloid species investigated so far. In this study, anhydrobiotic adults of a bdelloid species (Macrotrachela quadricornifera) and resting eggs of a monogonont species (Brachionus plicatilis) were analysed by thin layer chromatography and gas chromatography to detect the presence of trehalose. No trehalose was detected in the bdelloid, while the anhydrobiotic resting egg of the monogonont rotifer contained about 0.35% trehalose of its dry weight. Although very little, the presence of trehalose in B. plicatilis suggests that the trehalose synthase genes, absent in bdelloid rotifers, are present in non-bdelloid rotifers. [Copyright &y& Elsevier]

The new species Umbelopsis dimorpha sp. nov. was isolated from a soil sample in the Red Hills area of Mt Richmond Forest Park, in the northern part of the South Island of New Zealand. It has two kinds of pale pinkish sporangia: (1) single-spored, indistinguishable from those of U. versiformis; and (2) multi-spored, similar to those of U. vinacea. ITS sequences place the species in the immediate vicinity of the former species. [ABSTRACT FROM AUTHOR]

The development of the extraradical mycelium and auxiliary cells and spore production of Scutellospora reticulata in association with Ri T-DNA transformed carrot roots was followed under root-organ culture conditions. Extraradical mycelium development followed classical lag-exponential-plateau phases, with an additional late decline phase in number of auxiliary cells. Spore production started in parallel with a critical extraradical mycelium biomass produced, continued long after root growth ceased and during the late decline in auxiliary cells number. Isolated auxiliary cells were shown to exhibit hyphal re-growth, but not root colonization, either in situ or in vitro. These results showed that root and extraradical mycelium development were intimately associated in a sequence where both grew together during active root growth, followed during root aging by a period in which only the fungus developed. Spore production appeared dependent on a critical extraradical mycelium biomass and on the re-allocation of resources from both the intraradical mycelium and the auxiliary cells via the hyphal network. [ABSTRACT FROM AUTHOR]

Life is set within a narrow frame of physicochemical factors, yet, some species have adapted to conditions far beyond these constraints. Nature appears to have evolved two principal strategies for living organisms to cope with hostile conditions. One way is to remain active, retaining metabolism through adaptations that enable the organism to match the physiological requirements of environmental change. The other is to enter a state of dormancy with metabolic suppression. One form of metabolic suppression, known as cryptobiosis, is a widespread state across life kingdoms, in which metabolism comes to a reversible standstill. Among animals, nematodes, rotifers and tardigrades, comprise species that have the ability to enter cryptobiosis at all stages of their life cycle. Tardigrades are microscopic cosmopolitan metazoans found in permanent and temporal aquatic environments. They are renowned for their ability to tolerate extreme stress and are particularly resistant after having entered a cryptobiotic state known as a "tun". As new molecular tools allow for a more detailed investigation into their enigmatic adaptations, tardigrades are gaining increasing attention. In this graphical review, we provide an outline of survival strategies found among tardigrades and we summarize current knowledge of the adaptive mechanisms that underlie their unique tolerance to extreme or changing environments [ABSTRACT FROM AUTHOR]

Abstract: Neutron scattering is an exceptional tool to investigate structural and dynamical properties of systems of biophysical interest, such as proteins, enzymes, lipids and sugars. Moreover, elastic neutron scattering enhances the investigation of atomic motions in hydrated proteins in a wide temperature range and on the picosecond timescale. Homologous disaccharides, such as trehalose, maltose and sucrose, are cryptobiotic substances, since they allow to many organisms to undergo in a “suspended life” state, known as cryptobiosis in extreme environmental conditions. The present paper is aimed to discuss the fragility degree of disaccharides, as evaluated of the temperature dependence of the mean square displacement by elastic neutron scattering, in order to link this feature with their bioprotective functions. [Copyright &y& Elsevier]