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4.
Nat Commun ; 11(1): 5523, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173035

RESUMO

Microorganisms are employed to mine economically important elements from rocks, including the rare earth elements (REEs), used in electronic industries and alloy production. We carried out a mining experiment on the International Space Station to test hypotheses on the bioleaching of REEs from basaltic rock in microgravity and simulated Mars and Earth gravities using three microorganisms and a purposely designed biomining reactor. Sphingomonas desiccabilis enhanced mean leached concentrations of REEs compared to non-biological controls in all gravity conditions. No significant difference in final yields was observed between gravity conditions, showing the efficacy of the process under different gravity regimens. Bacillus subtilis exhibited a reduction in bioleaching efficacy and Cupriavidus metallidurans showed no difference compared to non-biological controls, showing the microbial specificity of the process, as on Earth. These data demonstrate the potential for space biomining and the principles of a reactor to advance human industry and mining beyond Earth.


Assuntos
Bactérias/metabolismo , Reatores Biológicos/microbiologia , Exobiologia , Gravitação , Metais Terras Raras/metabolismo , Bacillus subtilis/metabolismo , Cupriavidus/metabolismo , Microbiologia Industrial , Marte , Mineração , Lua , Silicatos , Sphingomonas/metabolismo , Ausência de Peso
5.
PLoS One ; 15(9): e0238606, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32936806

RESUMO

Given plans to revisit the lunar surface by the late 2020s and to take a crewed mission to Mars by the late 2030s, critical technologies must mature. In missions of extended duration, in situ resource utilization is necessary to both maximize scientific returns and minimize costs. While this present a significantly more complex challenge in the resource-starved environment of Mars, it is similar to the increasing need to develop resource-efficient and zero-waste ecosystems on Earth. Here, we make use of recent advances in the field of bioinspired chitinous manufacturing to develop a manufacturing technology to be used within the context of a minimal, artificial ecosystem that supports humans in a Martian environment.


Assuntos
Quitina/química , Exobiologia , Meio Ambiente Extraterreno , Marte
8.
Sci Rep ; 10(1): 10941, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616785

RESUMO

The transition of the martian climate from the wet Noachian era to the dry Hesperian (4.1-3.0 Gya) likely resulted in saline surface waters that were rich in sulfur species. Terrestrial analogue environments that possess a similar chemistry to these proposed waters can be used to develop an understanding of the diversity of microorganisms that could have persisted on Mars under such conditions. Here, we report on the chemistry and microbial community of the highly reducing sediment of Colour Peak springs, a sulfidic and saline spring system located within the Canadian High Arctic. DNA and cDNA 16S rRNA gene profiling demonstrated that the microbial community was dominated by sulfur oxidising bacteria, suggesting that primary production in the sediment was driven by chemolithoautotrophic sulfur oxidation. It is possible that the sulfur oxidising bacteria also supported the persistence of the additional taxa. Gibbs energy values calculated for the brines, based on the chemistry of Gale crater, suggested that the oxidation of reduced sulfur species was an energetically viable metabolism for life on early Mars.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , DNA Bacteriano/genética , Sedimentos Geológicos/análise , Marte , Enxofre/química , Bactérias/metabolismo , DNA Ribossômico/genética , Meio Ambiente Extraterreno , Filogenia , RNA Ribossômico 16S , Enxofre/metabolismo
11.
Sci Rep ; 10(1): 6, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913316

RESUMO

The current understanding of the Martian surface indicates that briny environments at the near-surface are temporarily possible, e.g. in the case of the presumably deliquescence-driven Recurring Slope Lineae (RSL). However, whether such dynamic environments are habitable for terrestrial organisms remains poorly understood. This hypothesis was tested by developing a Closed Deliquescence System (CDS) consisting of a mixture of desiccated Martian Regolith Analog (MRA) substrate, salts, and microbial cells, which over the course of days became wetted through deliquescence. The methane produced via metabolic activity for three methanogenic archaea: Methanosarcina mazei, M. barkeri and M. soligelidi, was measured after exposing them to three different MRA substrates using either NaCl or NaClO4 as a hygroscopic salt. Our experiments showed that (1) M. soligelidi rapidly produced methane at 4 °C, (2) M. barkeri produced methane at 28 °C though not at 4 °C, (3) M. mazei was not metabolically reactivated through deliquescence, (4) none of the species produced methane in the presence of perchlorate, and (5) all species were metabolically most active in the phyllosilicate-containing MRA. These results emphasize the importance of the substrate, microbial species, salt, and temperature used in the experiments. Furthermore, we show here for the first time that water provided by deliquescence alone is sufficient to rehydrate methanogenic archaea and to reactivate their metabolism under conditions roughly analogous to the near-subsurface Martian environment.


Assuntos
Exobiologia/métodos , Meio Ambiente Extraterreno , Marte , Metano/metabolismo , Methanosarcina/fisiologia , Sais/química , Água/química , Crescimento Quimioautotrófico , Metano/análise
12.
PLoS One ; 15(1): e0226434, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31967993

RESUMO

A round-trip human mission to Mars is anticipated to last roughly three years. Spaceflight conditions are known to cause loss of bone mineral density (BMD) in astronauts, increasing bone fracture risk. There is an urgent need to understand BMD progression as a function of spaceflight time to minimize associated health implications and ensure mission success. Here we introduce a nonlinear mathematical model of BMD loss for candidate human missions to Mars: (i) Opposition class trajectory (400-600 days), and (ii) Conjunction class trajectory (1000-1200 days). Using femoral neck BMD data (N = 69) from astronauts after 132-day and 228-day spaceflight and the World Health Organization's fracture risk recommendation, we predicted post-mission risk and associated osteopathology. Our model predicts 62% opposition class astronauts and 100% conjunction class astronauts will develop osteopenia, with 33% being at risk for osteoporosis. This model can help in implementing countermeasure strategies and inform space agencies' choice of crew candidates.


Assuntos
Astronautas/estatística & dados numéricos , Densidade Óssea , Marte , Osteoporose/etiologia , Voo Espacial , Ausência de Peso/efeitos adversos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico
13.
Curr Issues Mol Biol ; 38: 1-32, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31967574

RESUMO

Astrobiology asks three fundamental questions as outlined by the NASA Astrobiology Roadmap: 1. How did Life begin and evolve?; Is there Life elsewhere in the Universe?; and, What is the future of Life on Earth? As we gain perspective on how Life on Earth arose and adapted to its many niches, we too gain insight into how a planet achieves habitability. Here on Earth, microbial Life has evolved to exist in a wide range of habitats from aquatic systems to deserts, the human body, and the International Space Station (ISS). Landers, rovers, and orbiter missions support the search for signatures of Life beyond Earth, by generating data on surface and subsurface conditions of other worlds. These have provided evidence for water activity, supporting the potential for extinct or extant Life. To investigate the putative ecologies of these systems, we study extreme environments on Earth. Several locations on our planet provide analog settings to those we have detected or expect to find on neighboring and distant worlds. Whereas, the field of space biology uses the ISS and low gravity analogs to gain insight on how transplanted Earth-evolved organisms will respond to extraterrestrial environments. Modern genomics allows us to chronicle the genetic makeup of such organisms and provides an understanding of how Life adapts to various extreme environments.


Assuntos
Evolução Biológica , Exobiologia , Meio Ambiente Extraterreno/química , Origem da Vida , Água/metabolismo , Adaptação Biológica , Bactérias/crescimento & desenvolvimento , Bactérias/efeitos da radiação , Planeta Terra , Ecologia , Ecossistema , Ambientes Extremos , Humanos , Marte , Planetas , Estados Unidos , United States National Aeronautics and Space Administration , Água/análise , Água/química , Ausência de Peso/efeitos adversos
14.
Curr Issues Mol Biol ; 38: 53-74, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31967576

RESUMO

Carbon-based compounds are widespread throughout the Universe, including abiotic molecules that are the components of the life as we know it. This article reviews the space missions that have aimed to detect organic matter and biosignatures in planetary bodies of our solar system. While to date there was only one life-detection space mission, i.e., the Viking mission to Mars, several past and present space missions have searched for organic matter, paving the way for the future detection of signatures of extra-terrestrial life. This review also reports on the in-situ analysis of organic matter and sample-return missions from primitive bodies, i.e. comets and asteroids, providing crucial information on the conditions of the early solar system as well as on the building blocks of life delivered to the primitive Earth.


Assuntos
Carbono/química , Meio Ambiente Extraterreno/química , Compostos Orgânicos/química , Sistema Solar/química , Exobiologia , Cromatografia Gasosa-Espectrometria de Massas , História do Século XX , História do Século XXI , Marte , Meteoroides , Planetas Menores , Plutão , Saturno , Voo Espacial/história , Estados Unidos , United States National Aeronautics and Space Administration
15.
Curr Issues Mol Biol ; 38: 103-122, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31967578

RESUMO

Five bacterial (facultatively) anaerobic strains, namely Buttiauxella sp. MASE-IM-9, Clostridium sp. MASE-IM-4, Halanaerobium sp. MASE-BB-1, Trichococcus sp. MASE-IM-5, and Yersinia intermedia MASE-LG-1 isolated from different extreme natural environments were subjected to Mars relevant environmental stress factors in the laboratory under controlled conditions. These stress factors encompassed low water activity, oxidizing compounds, and ionizing radiation. Stress tests were performed under permanently anoxic conditions. The survival rate after addition of sodium perchlorate (Na-perchlorate) was found to be species-specific. The inter-comparison of the five microorganisms revealed that Clostridium sp. MASE-IM-4 was the most sensitive strain (D10-value (15 min, NaClO4) = 0.6 M). The most tolerant microorganism was Trichococcus sp. MASE-IM-5 with a calculated D10-value (15 min, NaClO4) of 1.9 M. Cultivation in the presence of Na-perchlorate in Martian relevant concentrations up to 1 wt% led to the observation of chains of cells in all strains. Exposure to Na-perchlorate led to a lowering of the survival rate after desiccation. Consecutive exposure to desiccating conditions and ionizing radiation led to additive effects. Moreover, in a desiccated state, an enhanced radiation tolerance could be observed for the strains Clostridium sp. MASE-IM-4 and Trichococcus sp. MASE-IM-5. These data show that anaerobic microorganisms from Mars analogue environments can resist a variety of Martian-simulated stresses either individually or in combination. However, responses were species-specific and some Mars-simulated extremes killed certain organisms. Thus, although Martian stresses would be expected to act differentially on microorganisms, none of the expected extremes tested here and found on Mars prevent the growth of anaerobic microorganisms.


Assuntos
Bactérias Anaeróbias/crescimento & desenvolvimento , Meio Ambiente Extraterreno , Ambientes Extremos , Bactérias Anaeróbias/efeitos dos fármacos , Bactérias Anaeróbias/efeitos da radiação , Carnobacteriaceae/efeitos dos fármacos , Carnobacteriaceae/crescimento & desenvolvimento , Carnobacteriaceae/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Clostridium/efeitos dos fármacos , Clostridium/crescimento & desenvolvimento , Clostridium/efeitos da radiação , Dessecação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/efeitos da radiação , Firmicutes/efeitos dos fármacos , Firmicutes/crescimento & desenvolvimento , Firmicutes/efeitos da radiação , Marte , Estresse Oxidativo , Percloratos/toxicidade , Tolerância a Radiação , Compostos de Sódio/toxicidade , Estresse Fisiológico/efeitos da radiação , Fatores de Tempo , Yersinia/efeitos dos fármacos , Yersinia/crescimento & desenvolvimento , Yersinia/efeitos da radiação
16.
Curr Issues Mol Biol ; 38: 163-196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31967580

RESUMO

The importance of hypopiezophilic and hypopiezotolerant microorganisms (i.e., life that grows at low atmospheric pressures; see section 2) in the field of astrobiology cannot be overstated. The ability to reproduce and thrive at Martian atmospheric pressure (0.2 to 1.2 kPa) is of high importance to both modeling the forward contamination of its planetary surface and predicting the habitability of Mars. On Earth, microbial growth at low pressure also has implications for the dissemination of microorganisms within clouds or the bulk atmosphere. Yet our ability to understand the effect of low pressure on microbial metabolism, growth, cellular structure and integrity, and adaptation is still limited. We present current knowledge on hypopiezophilic and hypopiezotolerant microorganisms, methods for isolation and cultivation, justify why there should be more focus for future research, and discuss their importance for astrobiology.


Assuntos
Bactérias/isolamento & purificação , Dessecação/métodos , Meio Ambiente Extraterreno , Adaptação Biológica/genética , Pressão Atmosférica , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Sobrevivência Celular , Dessecação/instrumentação , Exobiologia , Regulação da Expressão Gênica/genética , Marte , Filogenia , Temperatura
17.
J Surg Res ; 246: 305-314, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31731248

RESUMO

BACKGROUND: Long-duration exploration missions (LDEMs), such as voyages to Mars, will present unique medical challenges for astronaut crews, including communication delays and the inability to return to Earth early. Medical events threaten crewmember lives and increase the risk of mission failure. Managing a range of potential medical events will require excellent technical and nontechnical skills (NTSs). We sought to identify medical events with potential for rescue, range them according to the potential impact on crew health and mission success during LDEMs, and develop a list of NTSs to train for management of in-flight medical events. MATERIALS AND METHODS: Twenty-eight subject matter experts with specializations in surgery, medicine, trauma, spaceflight operations, NTS training, simulation, human factors, and organizational psychology completed online surveys followed by a 2-d in-person workshop. They identified and rated medical events for survivability, mission impact, and impact of crewmember NTSs on outcomes in space. RESULTS: Sudden cardiac arrest, smoke inhalation, toxic exposure, seizure, and penetrating eye injury emerged as events with the highest potential mission impact, greatest potential for survival, and that required excellent NTS for successful management. Key NTS identified to target in training included information exchange, supporting behavior, communication delivery, and team leadership/followership. CONCLUSIONS: With a planned Mars mission on the horizon, training countermeasures need to be developed in the next 3-5 y. These results may inform policy, selection, medical system design, and training scenarios for astronauts to manage in-flight medical events on LDEMs. Findings may extend to surgical and medical care in any rural and remote location.


Assuntos
Astronautas/educação , Marte , Voo Espacial/métodos , Sobrevivência , Astronautas/psicologia , Consenso , Morte Súbita Cardíaca , Ferimentos Oculares Penetrantes/terapia , Humanos , Liderança , Convulsões/terapia , Lesão por Inalação de Fumaça/terapia , Fatores de Tempo
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