深海底生物圏のプロカリオット細胞は,生きている細菌として識別されました
Axel Schippers1, Lev N Neretin, Jens Kallmeyer
1Section Geomicrobiology, Federal Institute for Geosciences and Natural Resources, Stilleweg 2, 30655 Hannover, Germany. a.schippers@bgr.de
Nature
|February 25, 2005
まとめ
海底のプロカリオットは,地球のシステムにとって不可欠です. 新しい研究は,触媒化されたレポーター堆積-光 in situ ハイブリダイゼーション (CARD-FISH) を使用して,深海の堆積物中の生微生物細胞を定量化し,有意な生息人口を明らかにしました.
科学分野:
- 微生物学 微生物学とは
- 地質化学 地質化学
- 海洋学 海洋学とは
背景:
- 海底のプロカリオットは,生地化学的サイクルにおいて重要な役割を果たします.
- 深海の沈殿物における微生物の活動は,海洋化学,メタンの排出,そして地球温暖化に影響を与える.
- 以前の海底微生物の推定値は,生細胞と死細胞を区別できない細胞数に基づいていた.
研究 の 目的:
- 深海の堆積物の中の生きた微生物の数を直接定量化するために.
- 古代および深い海底環境におけるプロカリオット細胞の生存可能性を決定する.
- これらの深層の微生物コミュニティの転機時間を評価する.
主な方法:
- 深海の沈殿物の化学分析 孔水.
- 海洋掘削プログラムの沈殿体核からの顕微鏡の細胞数値.
- リボソームRNAを標的にした,触媒化されたレポーター堆積-光 in situ ハイブリダイゼーション (CARD-FISH) を用いた生細胞の直接定量化.
主要な成果:
- 海底のプロカリオットのかなりの部分は,最大1600万年前の堆積物や400メートル以上の深さでも生きています.
- 検出されたすべての生きた細胞は,バクテリア領域に属していた.
- これらの深層の微生物集団の周回時間は,0.25年から22年までの地表堆積物の周回時間と同等であることが判明しました.
結論:
- 海底の生物圏は,これまで考えられていたよりも活発で,生きたプロカリオットの割合が著しい.
- 微生物の生命は,極端な深海の堆積物環境でも存続し,活発に活動しています.
- これらの発見は,海洋の炭素循環と地球規模の気候規制を理解するための意味を持つ.
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