Growth of terrestrial cyanobacterium, Nostoc sp., on Martian Regolith Simulant and its vacuum tolerance

Abstract

The growth of terrestrial cyanobacterium, Nostoc sp., on the Martian Regolith Simulant (MRS) and its vacuum tolerance were studied as one of our challenges in this century to inhabit Mars. The viability of the tested cyanobacteria was evaluated by microscopic observation after staining by fluorescein diacetate (FDA). The general terrestrial cyanobacterial lump collected from the ground showed a significantly high tolerance to a high vacuum environment (10 -5 Pa) for over one year. To scientifically elucidate its high tolerance function, Nostoc sp. HK-01 was used as another suitable scientific material for this study. After exposure to the high vacuum environment (10 -5 Pa) for two weeks, Nostoc sp. HK-01 began to grow again. Some of it was also re-incubated again with a liquid culture medium. The A'MED (Arai's Mars Ecosystem Dome) is designed to be installed on Mars for agricultural production. A'MED was useful to conduct our study. We performed the fundamental experiment using the MRS. Nostoc sp. HK-01 was found to grow for over 140 days along with having the normal function of chlorophyll synthesis on the MRS. These results show the possibility that cyanobacteria could adapt to the MRS, and grow under the low pressure environment expected on Mars.

Cyanobacteria for Space Agriculture on Mars

“…I am grateful to Dr. Kaori Tomita-Yokotani, Dr. Seigo Sato of Tsukuba University, Dr. Masayuki Ohmori of Saitama University, Dr. Hirofumi Hashimoto and Dr. Masamichi Yamashita of JAXA, co-author of the original paper (Arai et al, 2008). I wish to thank Dr. Hiroshi Takeda …”

The Heat Tolerance of Dry Colonies of a Terrestrial Cyanobacterium, <i>Nostoc</i> sp. HK-01

“…Fluorescein diacetate (FDA) staining method (Jones and Senft, 1985;Mori et al, 2002;Arai et al, 2008) was used as the viability assay. One mg of dissolved FDA in 0.5 ml dimethylsulfoxide and 0.2 ml acetone, which was kept in a refrigerator as an FDA stock solution.…”

“…HK-01 is one of the candidate species of terrestrial organisms for the introduction to Mars. Arai et al, (2008) reported that Nostoc sp. HK-01 could grow for a period of 140 days on Martian regolith simulant which does not include a carbon source or a nitrogen source.…”

“…Nostoc sp. HK-01 may be able to create organic soil from Martian regolith (Arai et al, 2008;Arai, 2009;Oarga, 2009).…”

“…HK-01 has not been investigated, although their tolerances to desiccation for 8 months, to 200 mM NaCl stress, and to vacuum (10 -5 Pa) for 2 weeks, have been investigated (Yoshimura et al, , 2012Arai et al, 2008;Arai, 2009). In low Earth orbit, the temperature of a body in space can become extremely high due to solar radiation (1,366 W m -2 ) and no convection.…”