古代の鉄を酸化する極端な酸性動物で,酸性鉱山の排水に重要な役割を果たしていた
K J Edwards1, P L Bond, T M Gihring
1Department of Geology and Geophysics, University of Wisconsin-Madison, 1215 West Dayton Street, Madison, WI 53706, USA. kedwards@whoi.edu
Science (New York, N.Y.)
|March 10, 2000
まとめ
新しく発見されたアーカイオンは,カリフォルニア州アイアンマウンテンで極度の酸性 (pH0.5) と適度な温度 (40°C) で繁栄しています. この鉄を酸化する微生物は,酸性鉱山の排水と生地化学的サイクルに大きく影響します.
科学分野:
- 微生物学 微生物学とは
- 環境科学 環境科学
- 地質化学 地質化学
背景:
- 極端な環境は,ユニークな微生物の生命を宿している.
- 酸性鉱山排水 (AMD) は重大な環境問題である.
- 硫化物鉱石体は,低pHと高金属濃度で特徴付けられています.
研究 の 目的:
- 酸性環境からの新しい考古学的種を特定し,特徴づけること.
- このアーケオンのAMDと要素サイクリングにおける役割を理解するために.
主な方法:
- カリフォルニア州アイアンマウンテンでのフィールドサンプリング.
- アーカイアを隔離し,特定するための顕微鏡および培養技術.
- 環境の物理化学分析 (pH,温度,伝導性).
主要な成果:
- pH 0.0で成長できる新種のアルカイアが発見されました.
- この鉄酸化アーカイオンは,ピライトと結合して40°Cで繁栄します.
- この種は,高伝導性スライムと堆積物における微生物コミュニティを支配し,高伝導性スライムと堆積物の割合は85%に達した.
結論:
- この酸性アーカイオンは,AMD環境における重要な役割を果たしています.
- この生物は,鉄と硫黄の生地化学サイクルに影響を与える可能性が高い.
- 熱プラズマは,酸性,金属に富んだ生息地の地化学に大きく貢献しています.
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