窒素性細菌によるニート駆動のアナーロビックメタンの酸化.
Katharina F Ettwig1, Margaret K Butler, Denis Le Paslier
1Radboud University Nijmegen, IWWR, Department of Microbiology, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands. k.ettwig@science.ru.nl
Nature
|March 26, 2010
まとめ
新しい無酸素メタン酸化細菌は,新しい代謝経路を介して酸素を生成します. この発見は,これまで未知の酸素の源を明らかにし,初期の地球に潜在的に影響を与えた.
科学分野:
- 微生物学 微生物学とは
- バイオジオケミストリー バイオジオケミストリー
- 進化生物学の進化生物学について
背景:
- 酸素の生産は主に光合成,塩酸呼吸,および活性酸素種の解毒に関連しています.
- 重要な淡水メタンシンクは,生化学的に説明がつかないままである.
- グローバルな生物地球化学サイクルにおける無酸素メタンの酸化の役割は極めて重要です.
研究 の 目的:
- 酸素生産のための新しい生物学的経路を特定し,特徴づけること.
- わかりにくい淡水メタンシンクの背後にある生化学的メカニズムを解明するために.
- 初期の酸素の利用可能性の進化的影響を調査する.
主な方法:
- アナーロビック濃縮培養物のメタゲノミクシーケンシング.
- 支配的なバクテリア"Candidatus Methylomirabilis oxyfera"の全ゲノムアセンブリを集めたものです.
- 代謝経路を追跡するための同位体ラベリング実験.
主要な成果:
- "Candidatus Methylomirabilis oxyfera"で4番目の酸素生成経路を発見した.
- このバクテリアは,窒素酸化物の変換から得られる酸素を使用して,無酸素メタンの酸化を行います.
- 生物はエアロビックメタンの酸化経路を無酸素で利用し,既知の二酸化窒素生成遺伝子が欠けています.
結論:
- 酸素生成のための新しい生化学的経路が特定されました.
- この経路は,重要な淡水メタンシンクを説明し,炭化水素の分解に影響を与える.
- 酸素 fotosynthesis 前に微生物の代謝のために酸素が利用可能であった可能性があります.
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