NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Microbiological Methodology in AstrobiologySearching for life in astromaterials to be delivered from the future missions to extraterrestrial bodies is undoubtedly related to studies of the properties and signatures of living microbial cells and microfossils on Earth. As model terrestrial analogs of Martian polar subsurface layers are often regarded the Antarctic glacier and Earth permafrost habitats where alive microbial cells preserved viability for millennia years due to entering the anabiotic state. For the future findings of viable microorganisms in samples from extraterrestrial objects, it is important to use a combined methodology that includes classical microbiological methods, plating onto nutrient media, direct epifluorescence and electron microscopy examinations, detection of the elemental composition of cells, radiolabeling techniques, PCR and FISH methods. Of great importance is to ensure authenticity of microorganisms (if any in studied samples) and to standardize the protocols used to minimize a risk of external contamination. Although the convincing evidence of extraterrestrial microbial life will may come from the discovery of living cells in astromaterials, biomorphs and microfossils must also be regarded as a target in search of life evidence bearing in mind a scenario that alive microorganisms had not be preserved and underwent mineralization. Under the laboratory conditions, processes that accompanied fossilization of cyanobacteria were reconstructed, and artificially produced cyanobacterial stromatolites resembles by their morphological properties those found in natural Earth habitats. Regarding the vital importance of distinguishing between biogenic and abiogenic signatures and between living and fossil microorganisms in analyzed samples, it is worthwhile to use some previously developed approaches based on electron microscopy examinations and analysis of elemental composition of biomorphs in situ and comparison with the analogous data obtained for laboratory microbial cultures and fossilized microorganisms. This communication will be focused on the analysis of our experience in working with ancient microorganisms and fossils and discussion of some issues that are crucial for development of the program for future finding of extraterrestrial life and its evidence.
Document ID
20050215630
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Abyzov, S. S.
(Academy of Sciences (Russia) Russia)
Gerasimenko, L. M.
(Academy of Sciences (Russia) Russia)
Hoover, R. B.
(National Space Science and Technology Center Huntsville, AL, United States)
Mitskevich, I. N.
(Academy of Sciences (Russia) Russia)
Mulyukin, A. L.
(Academy of Sciences (Russia) Russia)
Poglazova, M. N.
(Academy of Sciences (Russia) Russia)
Rozanov, A. Y.
(Academy of Sciences (Russia) Russia)
Date Acquired
August 23, 2013
Publication Date
January 1, 2005
Subject Category
Exobiology
Meeting Information
Meeting: The International Symposium of Optical Science and Technology 50th Annual Meeting: Instruments, Methods, and Missions for Astrobiology
Location: San Diego, CA
Country: United States
Start Date: July 31, 2005
End Date: August 4, 2005
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available