PCR-based analysis of microbial communities during the EuroGeoMars campaign at Mars Desert Research Station, Utah

The search for evidence of past or present life on Mars will require the detection of markers that indicate the presence of life. Because deoxyribonucleic acid (DNA) is found in all known living organisms, it is considered to be a ‘biosignature’ of life. The main function of DNA is the long-term storage of genetic information, which is passed on from generation to generation as hereditary material. The Polymerase Chain Reaction (PCR) is a revolutionary technique which allows a single fragment or a small number of fragments of a DNA molecule to be amplified millions of times, making it possible to detect minimal traces of DNA. The compactness of the contemporary PCR instruments makes routine sample analysis possible with a minimum amount of laboratory space. Furthermore the technique is effective, robust and straightforward. Our goal was to establish a routine for the detection of DNA from micro-organisms using the PCR technique during the EuroGeoMars simulation campaign. This took place at the Mars Society’s Mars Desert Research Station (MDRS) in Utah in February 2009 (organized with the support of the International Lunar Exploration Working Group (ILEWG), NASA Ames and the European Space Research and Technology Centre (ESTEC)). During the MDRS simulation, we showed that it is possible to establish a minimal molecular biology lab in the habitat for the immediate on-site analysis of samples by PCR after sample collection. Soil and water samples were taken at different locations and soil depths. The sample analysis was started immediately after the crew returned to the habitat laboratory. DNA was isolated from micro-organisms and used as a template for PCR analysis of the highly conserved ribosomal DNA to identify representatives of the different groups of micro-organisms (bacteria, archaea and eukarya). The PCR products were visualized by agarose gel electrophoresis and documented by transillumination and digital imaging. The microbial diversity in the collected samples was analysed with respect to sampling depth and the presence or absence of vegetation. For the first time, we have demonstrated that it is possible to perform direct on-site DNA analysis by PCR at MDRS, a simulated planetary habitat in an extreme environment that serves as a model for preparation and optimization of techniques to be used for future Mars exploration. DOI: https://doi.org/10.1017/S1473550411000073 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-61056 Published Version Originally published at: Thiel, C S; Ehrenfreund, P; Foing, B; Pletser, V; Ullrich, O (2011). PCR-based analysis of microbial communities during the EuroGeoMars campaign at Mars Desert Research Station, Utah. International Journal of Astrobiology, 10(3):177-190. DOI: https://doi.org/10.1017/S1473550411000073 PCR-based analysis of microbial communities during the EuroGeoMars campaign at Mars Desert Research Station, Utah Cora S. Thiel, Pascale Ehrenfreund, Bernard Foing, Vladimir Pletser and Oliver Ullrich Institute of Medical Physics and Biophysics, CeNTech, University of Muenster,Heisenbergstrasse 11, D-48149 Muenster, Germany e-mail: [email protected] Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, NL-2300 RA, Leiden, The Netherlands Science and Robotic Exploration Directorate, European Space Agency, ESTEC, P.O. Box 299, NL-2200 AG, Noordwijk, The Netherlands Human Space Flight Directorate, European Space Agency, ESTEC, P.O. Box 299, NL-2200 AG, Noordwijk, The Netherlands Institute of Anatomy, Faculty of Medicine, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland Department of Machine Design, Engineering Design and Product Development, Institute of Mechanical Engineering, Otto-von-Guericke-University Magdeburg, Universitätsplatz, D-39106 Magdeburg, Germany Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland Abstract: The search for evidence of past or present life on Mars will require the detection of markers that indicate the presence of life. Because deoxyribonucleic acid (DNA) is found in all known living organisms, it is considered to be a ‘biosignature’ of life. The main function of DNA is the long-term storage of genetic information, which is passed on from generation to generation as hereditarymaterial. The Polymerase Chain Reaction (PCR) is a revolutionary technique which allows a single fragment or a small number of fragments of a DNA molecule to be amplified millions of times, making it possible to detect minimal traces of DNA. The compactness of the contemporary PCR instruments makes routine sample analysis possible with a minimum amount of laboratory space. Furthermore the technique is effective, robust and straightforward. Our goal was to establish a routine for the detection ofDNA frommicro-organisms using the PCR technique during the EuroGeoMars simulation campaign. This took place at theMars Society’sMars Desert Research Station (MDRS) in Utah in February 2009 (organized with the support of the International Lunar Exploration Working Group (ILEWG), NASA Ames and the European Space Research and Technology Centre (ESTEC)). During the MDRS simulation, we showed that it is possible to establish a minimal molecular biology lab in the habitat for the immediate on-site analysis of samples by PCR after sample collection. Soil and water samples were taken at different locations and soil depths. The sample analysis was started immediately after the crew returned to the habitat laboratory. DNA was isolated from micro-organisms and used as a template for PCR analysis of the highly conserved ribosomal DNA to identify representatives of the different groups of micro-organisms (bacteria, archaea and eukarya). The PCR products were visualized by agarose gel electrophoresis and documented by transillumination and digital imaging. Themicrobial diversity in the collected samples was analysed with respect to sampling depth and the presence or absence of vegetation. For the first time, we have demonstrated that it is possible to perform direct on-site DNA analysis by PCR at MDRS, a simulated planetary habitat in an extreme environment that serves as a model for preparation and optimization of techniques to be used for future Mars exploration. The search for evidence of past or present life on Mars will require the detection of markers that indicate the presence of life. Because deoxyribonucleic acid (DNA) is found in all known living organisms, it is considered to be a ‘biosignature’ of life. The main function of DNA is the long-term storage of genetic information, which is passed on from generation to generation as hereditarymaterial. The Polymerase Chain Reaction (PCR) is a revolutionary technique which allows a single fragment or a small number of fragments of a DNA molecule to be amplified millions of times, making it possible to detect minimal traces of DNA. The compactness of the contemporary PCR instruments makes routine sample analysis possible with a minimum amount of laboratory space. Furthermore the technique is effective, robust and straightforward. Our goal was to establish a routine for the detection ofDNA frommicro-organisms using the PCR technique during the EuroGeoMars simulation campaign. This took place at theMars Society’sMars Desert Research Station (MDRS) in Utah in February 2009 (organized with the support of the International Lunar Exploration Working Group (ILEWG), NASA Ames and the European Space Research and Technology Centre (ESTEC)). During the MDRS simulation, we showed that it is possible to establish a minimal molecular biology lab in the habitat for the immediate on-site analysis of samples by PCR after sample collection. Soil and water samples were taken at different locations and soil depths. The sample analysis was started immediately after the crew returned to the habitat laboratory. DNA was isolated from micro-organisms and used as a template for PCR analysis of the highly conserved ribosomal DNA to identify representatives of the different groups of micro-organisms (bacteria, archaea and eukarya). The PCR products were visualized by agarose gel electrophoresis and documented by transillumination and digital imaging. Themicrobial diversity in the collected samples was analysed with respect to sampling depth and the presence or absence of vegetation. For the first time, we have demonstrated that it is possible to perform direct on-site DNA analysis by PCR at MDRS, a simulated planetary habitat in an extreme environment that serves as a model for preparation and optimization of techniques to be used for future Mars exploration. Received 15 December 2010, accepted 9 February 2011, first published online 22 March 2011