新しい無酸素微生物による鉄の腐食
Hang T Dinh1, Jan Kuever, Marc Mussmann
1Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany.
Nature
|February 27, 2004
まとめ
新しい海洋細菌と古生物は鉄を直接腐食し,無酸素腐食における水素の役割に異議を唱える. これらの微生物は,鉄の腐食メカニズムに関する新しい洞察を提供します.
科学分野:
- 微生物学 微生物学とは
- 腐食科学 腐食科学とは
- 電気化学 電気化学について
背景:
- 鉄の無酸素腐食は重要な経済問題であり,しばしば硫酸縮小細菌 (SRB) に起因する.
- 伝統的な考えでは,SRBは硫化水素の生産とカトジック水素の消費を通じて腐食を引き起こすと考えられています.
- SRBによって引き起こされる無酸素腐食の正確なメカニズムは,特に異なる細菌種の役割は,まだ完全に理解されていません.
研究 の 目的:
- 金属鉄を直接利用できる新しい海洋微生物を分離し,特徴づけること.
- これらの新たに特定された微生物による無酸素鉄の腐食のメカニズムを調査する.
- 鉄の腐食におけるSRBの役割に関する従来の理解に異議を唱える.
主な方法:
- 唯一の電子ドナーとして金属鉄を用いた海洋微生物の分離.
- 孤立したデスルフォバクテリア型およびメタノバクテリア型種の腐食率の評価.
- 新しい単離物の腐食活動と,水素を採取する既知のDesulfovibrio種を比較する.
主要な成果:
- デスルフォバクテリアのような単離体は,デスルフォビブリオ種と比較して,金属鉄による硫酸塩の減少が著しく速く示されました.
- 新しいメタノバクテリアのようなアーケオンは,既知のメタノゲンよりも早く鉄を用いてメタンを生成した.
- これらの発見は,これまで考えられていたよりも,金属鉄からの電子の吸収が,新種の分離物によってより直接に行われていることを示唆している.
結論:
- 新しい海洋SRBとメタノゲンは,金属鉄から電子を直接利用することができます.
- この直接的な電子伝送メカニズムは,水素の必要性を回避し,無酸素の腐食に関する新しい視点を提供します.
- この研究は,経済的に重要な鉄の腐食プロセスに関与する新しい微生物のプレーヤーとメカニズムを特定しています.
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