大きな硫黄細菌と,フォスフォライトの形成
Heide N Schulz1, Horst D Schulz
1Institute for Microbiology, University of Hannover, Schneiderberg 50, D-30167 Hannover, Germany. schulz@ifmb.uni-hannover.de
まとめ
巨大硫黄細菌のティオマーガリタ・ナミビエンシスは,海洋堆積物におけるフォスフォライト堆積物の形成を促しています. 彼らの活動により,リン酸塩が放出され,ナミビアのシェルフに鉱物の蓄積が大きくなります.
科学分野:
- 海洋地質学 海洋地質学
- 微生物学 微生物学とは
- 地質化学 地質化学
背景:
- 酸塩鉱床は,海洋環境におけるの重要な吸収源である.
- 鉱物形成の過程であるフォスフォゲネシスにおける微生物の役割は完全に理解されていません.
研究 の 目的:
- 巨大硫黄細菌のティオマーガリタ・ナミビエンシス (Thiomargarita namibiensis) とリン酸塩の形成との関連を調査する.
- ティオマーガリタ・ナミビエンシスの活動が海洋堆積物におけるアパタイトの豊富さに影響を与えているかどうかを判断する.
主な方法:
- ナミビアのシェルフ堆積物におけるアパタイトの大量とティオマーガリタ・ナミビエンシス (Thiomargarita namibiensis) の集団の相関分析.
- 堆積物における孔水リン酸塩濃度の測定.
- ティオマーガリタ・ナミビエンシス (Thiomargarita namibiensis) によるリン酸の放出を評価するために,無酸素状態をシミュレートした実験室での実験.
主要な成果:
- アパタイトの大量とチオマガリタ・ナミビエンシスの存在/活動との間に強い相関が観察されました.
- ティオマーガリタを含む堆積物には,高濃度のリン酸塩 (最大300マイクロモール) とかなりの量のリン酸塩の蓄積 (50gP/kg以上) が示された.
- 実験室での実験では,チオマガリタが,無毒条件下でヒドロキシアパタイトを沈殿させるのに十分な量のリン酸を放出することを確認しました.
結論:
- ティオマーガリタ・ナミビエンシスは,フォスフォゲネシスを推進する上で重要な役割を果たしています.
- 硫黄バクテリアは,海洋環境におけるフォスフォライト堆積物の形成に重要な役割を果たしています.
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