ゼロバレント硫黄は,海洋メタンの酸化における重要な中間物質である
Jana Milucka1, Timothy G Ferdelman, Lubos Polerecky
1Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany.
Nature
|November 9, 2012
まとめ
海洋古生物は,ゼロ価硫黄化合物を形成することによって,メタン (AOM) の無酸素酸化を独立して実行することができます. この発見は,AOMが炭素と硫黄の循環に影響を及ぼす強制的なシントロフィックプロセスであるとの見解に異議を唱える.
科学分野:
- 海洋微生物生態学について
- バイオジオケミカルサイクルとは
- 微生物の代謝とは
背景:
- 海洋沈殿物は,強力な温室効果ガスであるメタンの主要な供給源である.
- メタンの無酸素酸化 (AOM) と硫酸縮小は,メタン排出量の主要な制御です.
- 現在の理解では,AOMはメタノトロフィックアーカイア (ANME) と硫酸塩を減少させるデルタプロテオバクテリアの間のシントロフィックパートナーシップによって媒介される.
研究 の 目的:
- メタン (AOM) の硫酸相結合無酸素酸化 (AOM) のメカニズムを解明する.
- AOMにおけるメタノトロフィックアーキア (ANME) とデルタプロテオバクテリアの役割を調査する.
- 硫黄の変換における新しい微生物の経路を探求する.
主な方法:
- 海洋堆積物から研究された微生物コンソーシアム.
- メタンの無酸素酸化 (AOM) に関する代謝経路を分析した.
- AOM.における中介物質として特定された零価硫黄化合物 (S(0)).
主要な成果:
- メタノトロフィック・アーカイア (ANME) は,シミラートリ・スルファート・リドクションを行い,ゼロ・ヴァレンスの硫黄化合物 (S(0) を生成する.
- AOMはデルタプロテオバクテリアとは独立して発生し,義務性シントロフィックモデルに異議を唱える.
- 関連デルタプロテオバクテリアは,生成されたS(0) を不均衡にジスルファイド化します.
結論:
- ANMEにおける新たな硫酸還元経路の発見は,既知の微生物の硫黄変換を拡大する.
- AOMはシントロフィーを必要としない場合があり,ANMEは単独で作用する可能性があります.
- これらの発見は,海洋の炭素と硫黄の生地化学サイクルに関する私たちの理解を大幅に前進させます.
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