微生物マットの有酸素硫酸還元
1National Aeronautics and Space Administration-Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.
Science (New York, N.Y.)
|March 22, 1991
まとめ
バクテリア硫酸塩の減少は,高塩分マットの酸素化されたゾーンで観察され,このプロセスの無酸素要求に異議を唱えました. 光と酸素のレベルは,24時間サイクルのスルファート減少率に最小限の影響を及ぼしました.
科学分野:
- 微生物学 微生物学とは
- 地質化学 地質化学
- 環境科学 環境科学
背景:
- 溶解性硫酸還元は,伝統的に無酸素プロセスと考えられています.
- 超塩分環境は,特殊な代謝経路を持つユニークな微生物群を宿している.
研究 の 目的:
- 酸素化された高塩素微生物マットにおけるバクテリアスルファート減少の発生率と発生率を調査する.
- 硫酸塩の還元は完全に無酸素であるというパラダイムに異議を唱える.
主な方法:
- バクテリア硫酸塩の減少率のインサイト測定.
- 溶けた酸素 (O2) 濃度のモニタリングは,ハイパーサリンマット内で行われます.
- 酸化状態と無酸素状態での硫酸縮小の比較分析.
主要な成果:
- バクテリア硫酸塩の減少は,高塩酸マットの酸素が十分に供給された光合成領域内で一貫して発生しました.
- 昼間の酸素マットにおける硫酸塩の減少率は,夜間の無酸素マットにおける減少率と同等であった.
- 24時間サイクルの間の光とO2の変動は,硫酸塩の還元率にわずかな影響を及ぼしました.
結論:
- 酸素の存在下でも溶解性硫酸還元が起こり,既定の見解に反する.
- ハイパーサリンマットにおける微生物の硫酸縮小は,これまで考えられていたより,昼間の酸素変動に対して敏感性が低い.
- これらの発見は,極端な環境における生地化学サイクルを理解するための意味を持つ.
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