日本地球惑星科学連合2014年大会

講演情報

インターナショナルセッション(口頭発表)

セッション記号 B (地球生命科学) » B-AO 宇宙生物学・生命起源

[B-AO01_28AM2] Astrobiology: Origins, Evolution, Distribution of Life

2014年4月28日(月) 11:00 〜 12:41 502 (5F)

コンビーナ:*小林 憲正(横浜国立大学大学院工学研究院)、山岸 明彦(東京薬科大学生命科学部)、大石 雅寿(国立天文台天文データセンター)、田近 英一(東京大学大学院新領域創成科学研究科複雑理工学専攻)、掛川 武(東北大学大学院理学研究科地学専攻)、井田 茂(東京工業大学大学院理工学研究科地球惑星科学専攻)、座長:小林 憲正(横浜国立大学大学院工学研究院)、田近 英一(東京大学大学院新領域創成科学研究科複雑理工学専攻)

12:20 〜 12:35

[BAO01-P07_PG] DNA蛍光色素を用いたエアロゲルに衝突した微生物の検出

ポスター講演3分口頭発表枠

*河口 優子1杉野 朋弘2田端 誠1奥平 恭子3今井 栄一4矢野 創1長谷川 直1薮田 ひかる5小林 憲正6河合 秀幸7三田 肇8橋本 博文1横堀 伸一2山岸 明彦2 (1.宇宙航空研究開発機構宇宙科学研究所、2.東京薬科大学、3.会津大学、4.長岡技術科学大学、5.大阪大学、6.横浜国立大学、7.千葉大学、8.福岡工業大学)

キーワード:Aerogel, Space experiment, Hypervelocity impact experiment, DNA-specific fluorescence dye

We previously proposed an experiment (the Tanpopo mission) to capture microbes and organic compounds on the Japan Experimental Module of the International Space Station. An ultra low-density silica aerogel will be exposed to space for one year. After retrieving the aerogel, particle tracks and particles found in it will be visualized by fluorescence microscopy after staining it with a DNA-specific fluorescence dye. In preparation for this study, we simulated particle trapping in the aerogel so that methods could be developed to visualize the particles and their tracks. During the Tanpopo mission, particles that have an orbital velocity of about 8 km/s are expected to collide with the aerogel. To simulate these collisions, we shot Deinococcus radiodurans-containing Lucentite particles into an aerogel from a two-stage light-gas gun (acceleration 4.2 km/s). The shapes of the captured particles and their tracks and entrance holes were recorded with a microscope/camera system for further analysis. The size distribution of the captured particles was smaller than the original distribution, suggesting that the particles had fragmented. We were able to distinguish between microbial DNA and inorganic compounds after staining the aerogel with the DNA-specific fluorescence dye SYBR green I as the fluorescence of the stained DNA and the autofluorescence of the inorganic particles decay at different rates. The developed methods are suitable to determine if microbes exist at the International Space Station altitude.
Keywords: Aerogel, Space experiment, Hypervelocity impact experiment, DNA-specific fluorescence dye.