アルゼンチンは,カリフォルニア州モノレイクにある温泉のバイオフィルムで無酸素光合成を促します
Science (New York, N.Y.)
|August 16, 2008
まとめ
微生物のアルゼンチンの代謝は古代のもの. 科学者は無酸素環境で光に依存した酸化を発見し,初期の地球生命と呼吸の進化のための新しい経路を示唆しました.
科学分野:
- 微生物学 微生物学とは
- 地質化学 地質化学
- 天体生物学 アストロバイオロジー
背景:
- 微生物のアルゼンチンの代謝は,古代の起源があり,おそらく地球初期までさかのぼります.
- 化合物は地熱環境で多く存在し,微生物の生命に影響を与えます.
研究 の 目的:
- アノキシカルな条件下で微生物のヒ素代謝を調査する.
- アルゼンチンの変換における光合成の役割を調査する.
- 生命の初期におけるヒ素代謝の進化的影響を理解する.
主な方法:
- 微生物コミュニティの系統遺伝分析.
- アルゼンチンが豊富な環境で光合成細菌の培養.
- アルゼンチンの代謝経路の遺伝子分析.
主要な成果:
- 無酸素バイオフィルムにおける光に依存したアルセニート[As(III) ]からアルセニート[As(V) ]への酸化の発見.
- エクトチオロホドスピラ型の紫色の細菌とオシラトリア型のシアノバクテリアの特定.
- 電子ドナーとしてAs(III) を利用した光合成細菌は,逆の機能を持つ推定のAs(V) 還元酵素を有している.
結論:
- 無酸素光合成は,おそらく,原始的な地球上のヒ素循環に役割を果たした.
- このプロセスは,初期のアルセネート呼吸性プロカリオットのニッチを創ったのかもしれない.
- この発見は,古代の生態系におけるヒ素酸化のための新しい経路を示唆しています.
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