Feを代謝するバクテリアによる磁石中のFe (II) とFe (III) のレドックスサイクル
James M Byrne1, Nicole Klueglein2, Carolyn Pearce3
1Geomicrobiology, Center for Applied Geosciences, University of Tuebingen, Sigwartstrasse 10, 72076 Tuebingen, Germany. James.Byrne@uni-tuebingen.de.
まとめ
微生物は,磁石ナノ粒子を天然のバッテリーとして使用することができます. ある細菌は光を使って磁石を酸化し,別の細菌は磁石を減少させ,変化する環境における電子共有を示している.
科学分野:
- 環境微生物学 環境微生物学
- 地質化学 地質化学
- バイオジオケミカルサイクルとは
背景:
- 微生物は,環境における鉄酸化再酸化サイクルを駆動する.
- 細菌は,成長のために鉄鉱物からFe (II) とFe (III) を利用する.
- 異なる微生物の代謝の間の混合価鉄酸化物における電子共有は十分に理解されていません.
研究 の 目的:
- 異なる代謝を持つ細菌間の混合価鉄酸化物における電子の移転を調査する.
- 磁石ナノ粒子が微生物のプロセスにおける電子源と電子吸収源の両方で機能できるかどうかを判断する.
主な方法:
- マグネチットナノ粒子を分析するために,磁性およびスペクトル測定を用いた.
- コカルチャー実験は,Rhodopseudomonas palustris TIE-1とGeobacter sulfurreducens.と実施されました.
主要な成果:
- フォトトロフィック細菌であるRhodopseudomonas palustris TIE-1は,光エネルギーを使って磁石ナノ粒子を酸化する.
- この酸化プロセスは,同栽培における無酸素Fe (III) を減少させる細菌Geobacter sulfurreducensによって逆転する.
- 結晶磁石の鉄イオンは,電子ドナーおよび受容体として生物利用可能である.
結論:
- マグネタイトナノ粒子は,自然に発生するバッテリーとして機能し,微生物の電子移転を促進します.
- これは,変化する環境条件下で,混合価鉄酸化物における電子共有のメカニズムを示しています.
- 磁石の微生物による利用は,環境の酸化還元過程における磁石の役割を強調しています.
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