Metabolite Recycling In A Closed Biological Life Support System: Systemic Refinements And Acquisition Of Radioresistance Of Its Key Agent Spirulina Platensis

Paper number

IAC-07-A1.6.01

Author

Mr. Ingvar Bogdahn, Germany

Coauthor

Mr. Martin Gruhlke, Space Research Group, Germany

Coauthor

Ms. Britta Langen, Space Research Group, Germany

Year

2007

Abstract

In the ongoing project to build an autarkic habitat for a future research basis on Mars, students of biology continue to advance in the main work packages such as food production and efficient recycling loops of fresh water, decomposable waste and breathable air, aiming at an overall closed stock-flow system.
    Besides completion of system flow diagrams and respective overall input-output calculations of the main matter streams in the system our current focus amongst others lies on the optimization of fermentative food production. The organism considered particularily is Spirulina platensis as it optimally fits the alimentary needs. It provides all 20 amino acids, essential fatty acids, carbohydrates, minerals, pigments and other substances leading to a number of specific disease preventing effects, some of them proven in scientific experiments. Furthermore, we aim to maximize the share of the synergetic biological system on air revitalization and to minimize usage of the Sabatier reactor which constitutes a leak in the matter balance. To this end we conceive simple redundant controlling elements such as CO2-to-lime converters as flexible carbon reservoir on the one hand and biomolecular methods to increase CO2-assimilation and genereal photosynthesis throughput on the other hand. This could be achieved by promoting carbon-sinks in the Calvin-cycle or overexpressing endogene CO2 concentrating mechanisms.
    However, the evident danger of sterilization of the blue-algae due to long-term exposure to ionizing radiation and insufficient shielding is an unacceptable risk for a key role element in the system and needs to be resolved. Therefore, an empirical “training-effect” resulting from repeated cycles of irradiation and subsequent recovery of the surviving fraction, is applied to S. platensis in first laboratoy experiments. It was confirmed several times independently in literature that by each cycle, resistance to ionizing radiation such as gamma- and UV-radiation was progressively increased up to 20-fold and more. While performed on different standard model bacteria, it has never been tried on cyanobacteria nor has it been adapted to eukaryote algae so far. 
Additionally, as there is little theoretical basis for this induced radioresistance, it is envisioned to contribute to its elucidation by conducting basic genomic and proteomic analyses of new strains resulting from the radiation treatments, evaluate permanency of the acquired radioresistance and investigate the relationship to known stress response and DNA repair systems. Finally, it would be assured that neither the dietary value is compromised nor toxic substances are produced in possible radioresistant variants of S. platensis.

Abstract document

IAC-07-A1.6.01.pdf

Manuscript document

IAC-07-A1.6.01.pdf (🔒 authorized access only).

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