Spectral signs of life in ice
In astrobiology, new technologies are being implemented in the search for extraterrestrial life. Interpreting results from new analytical techniques requires additional information about microbial properties. A catalogue of identifying characteristics, called biosignatures was created for bacterial...
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Montana State University - Bozeman, College of Engineering
2020
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ftmontanastateu:oai:scholarworks.montana.edu:1/15896 2023-05-15T13:44:27+02:00 Spectral signs of life in ice Messmer, Mitch Wade Chairperson, Graduate Committee: Christine Foreman 2020 application/pdf https://scholarworks.montana.edu/xmlui/handle/1/15896 en eng Montana State University - Bozeman, College of Engineering https://scholarworks.montana.edu/xmlui/handle/1/15896 Copyright 2020 by Mitch Wade Messmer Microbiology Ice Exobiology Raman spectroscopy Thesis 2020 ftmontanastateu 2023-02-25T23:40:30Z In astrobiology, new technologies are being implemented in the search for extraterrestrial life. Interpreting results from new analytical techniques requires additional information about microbial properties. A catalogue of identifying characteristics, called biosignatures was created for bacterial and algal isolates from Greenland and Antarctica by measuring substrate utilization, UV/Vis absorbance, Fourier-Transform Infrared Spectroscopy, and Raman spectroscopy. Organisms were chosen from environments analogous to Martian glacier systems. Spectral properties of these polar isolates could serve as a reference for interpreting results from NASA's Perseverance rover. Substrate utilization was evaluated using EcoPlates on an Omnilog plate reader (Biolog, California, U.S.A.). UV/Vis absorbance spectra indicated that nine of the twenty-five bacterial isolates contained carotenoid pigments, and one contained violacein. UV/Vis analysis was effective at identifying the presence of pigments, but was insufficient for distinguishing between the types of carotenoids. FTIR analysis identified general biological features such as lipids, proteins, and carbohydrates, but did not detect pigments. Raman analysis of isolates with a 532 nm laser identified both the presence of carotenoid and violacein pigments, and the general cell features observed with FTIR. The degree of saturation of membrane lipids was evaluated for the bacterial isolates by comparing the ratio of unsaturated and saturated fatty acid peaks in the Raman spectra. Results were similar for the polar isolates and mesophiles, excluding the Bacillus subtilis spores. A principal component analysis was conducted to determine the regions of the spectra that contributed the variability between samples. The spectra of the bacterial isolates were more closely related based on colony color than phylogeny. Analysis of the algal isolates indicated that chlorophyll A and B fluoresced under exposure to the 532 nm laser, creating definitive biosignatures for algae. These ... Thesis Antarc* Antarctica glacier Greenland Montana State University (MSU): ScholarWorks Greenland Perseverance ENVELOPE(162.200,162.200,-76.800,-76.800) |
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Montana State University (MSU): ScholarWorks |
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ftmontanastateu |
language |
English |
topic |
Microbiology Ice Exobiology Raman spectroscopy |
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Microbiology Ice Exobiology Raman spectroscopy Messmer, Mitch Wade Spectral signs of life in ice |
topic_facet |
Microbiology Ice Exobiology Raman spectroscopy |
description |
In astrobiology, new technologies are being implemented in the search for extraterrestrial life. Interpreting results from new analytical techniques requires additional information about microbial properties. A catalogue of identifying characteristics, called biosignatures was created for bacterial and algal isolates from Greenland and Antarctica by measuring substrate utilization, UV/Vis absorbance, Fourier-Transform Infrared Spectroscopy, and Raman spectroscopy. Organisms were chosen from environments analogous to Martian glacier systems. Spectral properties of these polar isolates could serve as a reference for interpreting results from NASA's Perseverance rover. Substrate utilization was evaluated using EcoPlates on an Omnilog plate reader (Biolog, California, U.S.A.). UV/Vis absorbance spectra indicated that nine of the twenty-five bacterial isolates contained carotenoid pigments, and one contained violacein. UV/Vis analysis was effective at identifying the presence of pigments, but was insufficient for distinguishing between the types of carotenoids. FTIR analysis identified general biological features such as lipids, proteins, and carbohydrates, but did not detect pigments. Raman analysis of isolates with a 532 nm laser identified both the presence of carotenoid and violacein pigments, and the general cell features observed with FTIR. The degree of saturation of membrane lipids was evaluated for the bacterial isolates by comparing the ratio of unsaturated and saturated fatty acid peaks in the Raman spectra. Results were similar for the polar isolates and mesophiles, excluding the Bacillus subtilis spores. A principal component analysis was conducted to determine the regions of the spectra that contributed the variability between samples. The spectra of the bacterial isolates were more closely related based on colony color than phylogeny. Analysis of the algal isolates indicated that chlorophyll A and B fluoresced under exposure to the 532 nm laser, creating definitive biosignatures for algae. These ... |
author2 |
Chairperson, Graduate Committee: Christine Foreman |
format |
Thesis |
author |
Messmer, Mitch Wade |
author_facet |
Messmer, Mitch Wade |
author_sort |
Messmer, Mitch Wade |
title |
Spectral signs of life in ice |
title_short |
Spectral signs of life in ice |
title_full |
Spectral signs of life in ice |
title_fullStr |
Spectral signs of life in ice |
title_full_unstemmed |
Spectral signs of life in ice |
title_sort |
spectral signs of life in ice |
publisher |
Montana State University - Bozeman, College of Engineering |
publishDate |
2020 |
url |
https://scholarworks.montana.edu/xmlui/handle/1/15896 |
long_lat |
ENVELOPE(162.200,162.200,-76.800,-76.800) |
geographic |
Greenland Perseverance |
geographic_facet |
Greenland Perseverance |
genre |
Antarc* Antarctica glacier Greenland |
genre_facet |
Antarc* Antarctica glacier Greenland |
op_relation |
https://scholarworks.montana.edu/xmlui/handle/1/15896 |
op_rights |
Copyright 2020 by Mitch Wade Messmer |
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1766201751756603392 |