[H-CG24] Advanced life support systems with closed bio-ecosystems and thier applications

[HCG24-P02] Expression analysis of genes of terrestrialt cyanobacterium Nostoc sp. HK-01 under dry-wet conditions

*Kengo Shibasaki¹, Hiroshi Katoh², Kaori Tomita-Yokotani³, Tomoko Abe¹ (1.Graduate School of Life Science and Engineering, Tokyo Denki University, 2.Division of Plant Functional Genomics, Advanced Science Research Promotion Center, Mie University, 3.Faculty of Life and Environmental Sciences, University of Tsukuba)

Keywords:Cyanobacteria, Drought tolerance

Nostoc sp. HK-01 strain was clarified that the dried cells were resistant to harsh environments, such as dry condition. It has been reported that dried cells of this strain exhibit extremely high tolerance to harsh environments¹⁾. Therefore, it is expected to be used for material circulation systems and food resources in closed space. It is essential to establish preparation/production methods for the dried cells of this strain with environmental tolerance against conditions as harsh as possible to endure the space environment. We aimed to accumulate relevant information regarding genes and their products found specifically in their life cycle stages. In this study, Nostoc sp. HK-01 genes and proteins whose expression varied during the transition from wet to dry and dry to wet conditions, which are thought to induce the resistance mechanism, were analyzed.
Cells of Nostoc sp. HK-01 in wet conditions were dried gradually in a desiccator and collected partially and chronologically to be subjected to two-dimensional electrophoresis, and proteins in the cells were observed. Likewise, cells in the resuscitation process were collected and analyzed. As a result, multiple genes and proteins such as heat-shock proteins whose abundance would increase or decrease according to the decrease of water content or the progress of the resuscitation process were detected.

References:
1. Tomita-Yokotani, K. et al., Astrobiology 21, 1506-1514, 2021.