Location: Invasive Species and Pollinator HealthTitle: A simplified laboratory model of a Martian saline seep and its implications for planetary protection
|METTLER, MADELINE - Montana State University|
|GOEMANN, HANNAH - Montana State University|
|VENEGAS, OSCAR - University Of Georgia|
|LOPEZ, GABRIELA - Georgia State University|
|SINGH, NITIN - National Aeronautics And Space Administration (NASA)|
|VENKATESWARAN, KASTHURI - National Aeronautics And Space Administration (NASA)|
|PEYTON, BRENT - Montana State University|
Submitted to: Biofilms
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/21/2023
Publication Date: 5/13/2013
Citation: Mettler, M., Goemann, H.M., Mueller, R.C., Venegas, O., Lopez, G., Singh, N., Venkateswaran, K., Peyton, B.M. 2013. A simplified laboratory model of a Martian saline seep and its implications for planetary protection. Biofilms. 5:100127.
Interpretive Summary: Efforts to determine if life exists on Mars necessitates exploration with spacecraft launched from Earth, bringing with it inherent risks of contamination of Mars with organisms present on Earth. Extreme environments present in Earth, including high salinity sites, host organisms that could potentially survive known environmental conditions on Mars. Here, we used simple bioreactor experiments to examine the response of halophilic organisms to different media, light and oxygen conditions in order to determine the potential for these types of organisms to colonize Mars via contaminated probes. We compared the organisms observed to those found in cleanrooms, which are sites of decontamination prior to launch. We found overlap between the two datasets, suggesting that spacecraft could potentially transfer organisms that can survive the Martian environment, with unintended effects on currently established life on Mars, suggesting that additional decontamination efforts are needed to minimize these risks.
Technical Abstract: While life on Mars, extinct nor extant, has not been found, there exists the possibility of Earth-based life forms, specifically microorganisms, contaminating the Red Planet during rover expeditions as well as human exploration. Due to the survival advantages conferred by the biofilm morphology to microorganisms over the planktonic morphology, biofilms are particularly concerning from a planetary protection perspective. Temporary liquid water might exist on Mars in the form of high salinity brines. These brines could provide opportunities for microorganisms to take hold. In order to begin to test to potential for establishment of microbes on Mars, this project included a laboratory model of a simplified Martian saline seep inoculated with soil from a terrestrial saline seep, Hailstone Basin. The seep was modeled in a drip flow reactor at room temperature fed media with either 1 M NaCl or 1 M MgSO4. Biofilms were established within the first sampling point of each experiment. Endpoint community analysis showed a significant selection of microorganisms by the media. Additionally, we identified 14 taxa that were present in the model seep which have been isolated in NASA cleanrooms and should be considered potential threats for planetary protection.