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

[HCG24-P03] Expression analysis of genes in desiccation tolerant cyanobacterium Nostoc sp. HK-01

*Kengo Shibasaki¹, Midori Ong², Miku Tokita², Kaori Tomita-Yokotani³, Hiroshi Katoh⁴, Tomoko Abe⁵ (1.Tokyo Denki University, 2.University of Tsukuba, 3.Faculty of LIfe and Environmental Sciences University of Tsukuba, 4.Advanced Science Research Promotion Center, Organizasion for Research Initiative and Promotion, Mie University, 5.School of Science and Engineering, Tokyo Denki University)

Keywords:cyanobacteria, drought tolerance

Terrestrial cyanobacterium Nostoc sp. HK-01 is expected to the use in material circulation systems in a closed environment in space or food resources¹⁾. 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 harsh environment of space travel. As the first step to this end, this study aimed to accumulate relevant information regarding genes and their products found specifically in the drying process. Cells were exposed to a low-moisture environment to identify genes induced in the process of transition from wet to dry conditions or vice-versa by proteome and transcriptome analyses.
Nostoc sp. HK-01 cells 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 in the same manner. As a result, the presence of multiple proteins was confirmed, whose abundance would increase or decrease according to the decrease of water content or the progress of the resuscitation process. These proteins were identified, their functions were analyzed, and the changes in their gene expression amount during the drying/resuscitation process were investigated in detail.

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