プロカリオットによって媒介された地中海プレイストセンのサプロペルの進行中の改変
Marco J L Coolen1, Heribert Cypionka, Andrea M Sass
1Paleomicrobiology Group, Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Post Office Box 2503, D-26111 Oldenburg, Germany.
Science (New York, N.Y.)
|June 29, 2002
まとめ
古代地中海の沈殿物は,主として未知の緑色非硫黄の細菌とCrenarchaeotaである活発な微生物のコミュニティをホストしています. これらの微生物は代謝的に活性であり,有機に富んだサプロペルの層内の古代の炭素基板を分解します.
科学分野:
- マリン・マイクロバイオロジー
- 地質化学 地質化学
- パレオセアノグラフィー
背景:
- 地中海東部のプレイストセーン後期のサプロペルは,ケモオルガノトロフィック prokaryotes を含んでいます.
- これらの有機に富んだ層は,周囲の炭素の少ない堆積物と対照的です.
研究 の 目的:
- 古代サプロペルの層内の微生物の生命と代謝活動の調査.
- これらの堆積物における炭素循環に責任を負う重要な微生物のプレーヤーを特定する.
主な方法:
- 微生物の細胞数と水溶性エクソ酵素の活性に関する分析.
- アナーロビック・グルコースの分解速度の測定.
- 微生物コミュニティの分析のための16SリボソームRNA遺伝子シーケンシング.
主要な成果:
- サプロペルは,中間層と比較して,細胞密度が高く,微生物の活動が強化された.
- 緑の非硫黄細菌 (最大70%) とCrenarchaeota (16%) が支配的な微生物群であった.
- 進行中の代謝プロセスを示す,遅いが重要なグルコースの周回量の証拠.
結論:
- 古代のサプロペルは,代謝的に活発な微生物群を宿している.
- 緑の非硫黄細菌とCrenarchaeotaは,これらの古代の堆積物を変化させる上で重要な役割を果たしています.
- 最大21万7000年前のサプロペルの内にある微生物の炭素基板が利用されています.
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