scholarly journals Persistence of Biomarker ATP and ATP-Generating Capability in Bacterial Cells and Spores Contaminating Spacecraft Materials under Earth Conditions and in a Simulated Martian Environment

2008 ◽  
Vol 74 (16) ◽  
pp. 5159-5167 ◽  
Author(s):  
Patricia Fajardo-Cavazos ◽  
Andrew C. Schuerger ◽  
Wayne L. Nicholson
Keyword(s):  
Bacillus Pumilus ◽  
Surface Radiation ◽  
Dominant Factor ◽  
Bacterial Cells ◽  
Gas Composition ◽  
Martian Surface ◽  
Full Spectrum ◽  
Planetary Protection ◽  
Surface Conditions ◽  
Uv C

ABSTRACTMost planetary protection research has concentrated on characterizing viable bioloads on spacecraft surfaces, developing techniques for bioload reduction prior to launch, and studying the effects of simulated martian environments on microbial survival. Little research has examined the persistence of biogenic signature molecules on spacecraft materials under simulated martian surface conditions. This study examined how endogenous adenosine-5′-triphosphate (ATP) would persist on aluminum coupons under simulated martian conditions of 7.1 mbar, full-spectrum simulated martian radiation calibrated to 4 W m−2of UV-C (200 to 280 nm), −10°C, and a Mars gas mix of CO2(95.54%), N2(2.7%), Ar (1.6%), O2(0.13%), and H2O (0.03%). Cell or spore viabilities ofAcinetobacter radioresistens, Bacillus pumilus, andB. subtiliswere measured in minutes to hours, while high levels of endogenous ATP were recovered after exposures of up to 21 days. The dominant factor responsible for temporal reductions in viability and loss of ATP was the simulated Mars surface radiation; low pressure, low temperature, and the Mars gas composition exhibited only slight effects. The normal burst of endogenous ATP detected during spore germination inB. pumilusandB. subtiliswas reduced by 1 or 2 orders of magnitude following, respectively, 8- or 30-min exposures to simulated martian conditions. The results support the conclusion that endogenous ATP will persist for time periods that are likely to extend beyond the nominal lengths of most surface missions on Mars, and planetary protection protocols prior to launch may require additional rigor to further reduce the presence and abundance of biosignature molecules on spacecraft surfaces.

scholarly journals MARSBOx: Fungal and Bacterial Endurance From a Balloon-Flown Analog Mission in the Stratosphere

2021 ◽  
Vol 12 ◽  
Author(s):  
Marta Cortesão ◽  
Katharina Siems ◽  
Stella Koch ◽  
Kristina Beblo-Vranesevic ◽  
Elke Rabbow ◽  
...  
Keyword(s):  
Fungal Spores ◽  
Bacterial Cells ◽  
Martian Surface ◽  
Protection Measures ◽  
Planetary Protection ◽  
Log Reduction ◽  
Staphylococcus Capitis ◽  
Terrestrial Life ◽  
Survival Potential ◽  
Uv Dose

Whether terrestrial life can withstand the martian environment is of paramount interest for planetary protection measures and space exploration. To understand microbial survival potential in Mars-like conditions, several fungal and bacterial samples were launched in September 2019 on a large NASA scientific balloon flight to the middle stratosphere (∼38 km altitude) where radiation levels resembled values at the equatorial Mars surface. Fungal spores of Aspergillus niger and bacterial cells of Salinisphaera shabanensis, Staphylococcus capitis subsp. capitis, and Buttiauxella sp. MASE-IM-9 were launched inside the MARSBOx (Microbes in Atmosphere for Radiation, Survival, and Biological Outcomes Experiment) payload filled with an artificial martian atmosphere and pressure throughout the mission profile. The dried microorganisms were either exposed to full UV-VIS radiation (UV dose = 1148 kJ m−2) or were shielded from radiation. After the 5-h stratospheric exposure, samples were assayed for survival and metabolic changes. Spores from the fungus A. niger and cells from the Gram-(–) bacterium S. shabanensis were the most resistant with a 2- and 4-log reduction, respectively. Exposed Buttiauxella sp. MASE-IM-9 was completely inactivated (both with and without UV exposure) and S. capitis subsp. capitis only survived the UV shielded experimental condition (3-log reduction). Our results underscore a wide variation in survival phenotypes of spacecraft associated microorganisms and support the hypothesis that pigmented fungi may be resistant to the martian surface if inadvertently delivered by spacecraft missions.

Extended survival of several organisms and amino acids under simulated martian surface conditions

Icarus ◽  
2011 ◽  
Vol 211 (2) ◽  
pp. 1162-1178 ◽  
Author(s):  
A.P. Johnson ◽  
L.M. Pratt ◽  
T. Vishnivetskaya ◽  
S. Pfiffner ◽  
R.A. Bryan ◽  
...  
Keyword(s):  
Amino Acids ◽  
Martian Surface ◽  
Surface Conditions ◽  
Extended Survival

Ion Bombardment as Dominant Factor in Plasma Cryo-Etching for High Aspect Ratio Silicon Structures

2007 ◽  
Author(s):  
Dejiang Lu ◽  
Zhuangde Jiang ◽  
Jiuhong Wang
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Ion Bombardment ◽  
Dominant Factor ◽  
Chamber Pressure ◽  
Gas Composition ◽  
Surface Chemical Reaction ◽  
Experiment Data ◽  
Silicon Structures ◽  
Process Factors

SF6/O2 Plasma cryo-etching is discussed to show that it is a promising technology for etching the high aspect ratio silicon structures. Through a series of etching experiments, process factors including chuck temperature, gas composition, chamber pressure and ICP coil power are variated to show their influences to the etching results. Some valuable details of the experiment data point to some key mechanisms of the cryo-etching. It is not the surface chemical reaction but the ion bombardment that dominates the cyro-etching process in most cases. Notching near to the mask is due to the discharging effects of dielectric layer, and ARDE effect here is also different from the usual etching processes but is driven by the sidewall step coverage effect to the ion sputtering.

scholarly journals Transport processes induced by metastable boiling water under Martian surface conditions

2016 ◽  
Vol 9 (6) ◽  
pp. 425-428 ◽  
Author(s):  
M. Massé ◽  
S. J. Conway ◽  
J. Gargani ◽  
M. R. Patel ◽  
K. Pasquon ◽  
...  
Keyword(s):  
Transport Processes ◽  
Boiling Water ◽  
Martian Surface ◽  
Surface Conditions

Bacterial Flagella

1971 ◽  
Vol 29 ◽  
pp. 330-331
Author(s):  
Henry Koffler
Keyword(s):  
Amino Acid ◽  
Cell Surface ◽  
Self Assembly ◽  
Bacillus Pumilus ◽  
Entire Length ◽  
Bacterial Cells ◽  
Tryptic Peptides ◽  
Bacterial Flagella ◽  
Unique Protein ◽  
Basal Structure

Movement of bacterial cells is accomplished through the action of flagella, organelles consisting of three morphologically distinct portions, a spiral tubular filament [(f)n] which constitutes over 90% of the organelle, an extracellular hook, and a basal structure, which is intimately associated with the cell surface. The spiral (f)n is constructed of polarly oriented ovoid subunits of flagellin (f) apparently arranged in a helical fashion. Flagellin is a unique protein in that it contains no or only few residues of cys/2, trp, pro, his, or tyr, and is capable of forming normal (f)n by self-assembly. In cells of Bacillus pumilus 101 (f)n contains two types of f(fA,fB) in a ratio of 7:3. Amino acid analyses and examination of the tryptic peptides from purified fA and fB indicate that both molecules are much alike. Both fA and fB are synthesized by the same cell and are located within the same flagellum, since both anti-fA and anti-fB sera, which react specifically with synthetic (fA)n or (fB)n can be seen to coat native (f)n of all cells and the entire length of each (f)n when examined electron microscopically.

Spectral reflectance properties of minerals exposed to martian surface conditions: Implications for spectroscopy-based mineral detection on Mars

2021 ◽  
pp. 105377
Author(s):  
Nathalie Turenne ◽  
Alexis Parkinson ◽  
Daniel M. Applin ◽  
Paul Mann ◽  
Edward A. Cloutis ◽  
...  
Keyword(s):  
Spectral Reflectance ◽  
Martian Surface ◽  
Surface Conditions ◽  
Mineral Detection

scholarly journals Alteration of Proteomes in First-Generation Cultures of Bacillus pumilus Spores Exposed to Outer Space

mSystems ◽  
2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Abby J. Chiang ◽  
Ganesh Babu Malli Mohan ◽  
Nitin K. Singh ◽  
Parag A. Vaishampayan ◽  
Markus Kalkum ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Bacillus Pumilus ◽  
Outer Space ◽  
Space Station ◽  
Ground Control ◽  
Bacterial Survival ◽  
Planetary Protection ◽  
Content Type ◽  
Atp Production ◽  
Enhanced Resistance

ABSTRACT Bacillus pumilus SAFR-032 was originally isolated from the Jet Propulsion Lab Spacecraft Assembly Facility and thoroughly characterized for its enhanced resistance to UV irradiation and oxidative stress. This unusual resistance of SAFR-032 is of particular concern in the context of planetary protection and calls for development of novel disinfection techniques to prevent extraterrestrial contamination. Previously, spores of SAFR-032 were exposed for 18 months to a variety of space conditions on board the International Space Station to investigate their resistance to Mars-like conditions and space travel. Here, proteomic characterization of vegetative SAFR-032 cells from space-surviving spores is presented in comparison to a ground control. Vegetative cells of the first passage were processed and subjected to quantitative proteomics using tandem mass tags. Approximately 60% of all proteins encoded by SAFR-032 were identified, and 301 proteins were differentially expressed among the strains. We found that proteins predicted to be involved in carbohydrate transport/metabolism and energy production/conversion had lower abundance than those of the ground control. For three proteins, we showed that the expected metabolic activities were decreased, as expected with direct enzymatic assays. This was consistent with a decrease of ATP production in the space-surviving strains. The same space-surviving strains showed increased abundance of proteins related to survival, growth advantage, and stress response. Such alterations in the proteomes provide insights into possible molecular mechanisms of B. pumilus SAFR-032 to adapt to and resist extreme extraterrestrial environments. IMPORTANCE Spore-forming bacteria are well known for their resistance to harsh environments and are of concern for spreading contamination to extraterrestrial bodies during future life detection missions. Bacillus pumilus has been regularly isolated from spacecraft-associated surfaces and exhibited unusual resistance to ultraviolet light and other sterilization techniques. A better understanding of the mechanisms of microbial survival and enhanced resistance is essential for developing novel disinfection protocols for the purpose of planetary protection. While genomic analyses did not reveal the unique characteristics that explain elevated UV resistance of space-exposed B. pumilus, the proteomics study presented here provided intriguing insight on key metabolic changes. The observed proteomics aberrations reveal a complex biological phenomenon that plays a role in bacterial survival and adaptation under long-term exposure to outer space. This adaptive ability of microorganisms needs to be considered by those tasked with eliminating forward contamination.

Sign in / Sign up

Export Citation Format

Share Document