GFAJ-1は,アルセネートに耐性のある,リン酸に依存した生物です
Tobias J Erb1, Patrick Kiefer, Bodo Hattendorf
1Institute of Microbiology, Eidgenössische Technische Hochschule Zurich, Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland. toerb@ethz.ch
まとめ
バクテリアGFAJ-1は,低リン酸と高アルセネートで成長できますが,生き残るためにリン酸が必要です. この研究は,GFAJ-1が酸塩耐性であるが,酸塩依存性であり,酸塩ベースの生命体ではないことを確認しています.
科学分野:
- 微生物学 微生物学とは
- バイオケミストリー バイオケミストリー
- 天体生物学 アストロバイオロジー
背景:
- 細菌GFAJ-1は以前,成長のためにリンゴの代わりにヒ素を使用することを提案されていました.
- この仮説は,生命の新たな形態を提案し,基本的な生化学的原理に挑戦した.
研究 の 目的:
- GFAJ-1の成長要件と生化学組成を,異なるリン酸塩とヒ素酸塩条件下で調査する.
- GFAJ-1がヒ素をリンに代用できるかどうかを決定的に決定する.
主な方法:
- GFAJ-1の培養は,フォスファートとアルセネートの濃度が制御されている媒介で実施する.
- 高解像度質量スペクトロメトリーは,細胞代謝産物と核酸を分析します.
- 誘導結合プラズマ質量スペクトロメトリーは,アルゼンとリン含有量を定量化します.
主要な成果:
- GFAJ-1は低リン酸 (1.7μM) と高アルセネート (40mM) の環境で成長するが,リンが乏しい環境では成長しない.
- リン酸化代謝産物と核酸が優勢であった.
- 検出されたアルセニル化化合物は,アビオティックに形成されていることが判明しました. 核酸ではアルセニックが検出されませんでした.
結論:
- GFAJ-1は,アルセネート耐性細菌である.
- GFAJ-1は,成長と生存のためにリン酸に依存しています.
- バクテリアは,その核生物化学において,をアルゼンチンの代わりにはしない.
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