海洋プランクトンから得られた新しい主要なアーカイバクテリア群である
J A Fuhrman1, K McCallum, A A Davis
1Department of Biological Sciences, University of Southern California, Los Angeles 90089-0371.
Nature
|March 12, 1992
まとめ
海洋アーカイア (バクテリアと根本的に異なる生物) は,太平洋の奥深くで発見されました. この発見は,海洋生態系における微生物の多様性と初期の生命の進化に関する私たちの理解を広げています.
科学分野:
- マリン・マイクロバイオロジー
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
背景:
- 海洋バクテリアは海洋生態系の鍵ですが,その多様性は,培養の制限のために過小評価されています.
- 現在の方法では,海洋生物の99%が見逃され,正確な多様性評価を妨げています.
- 16S rRNA遺伝子配列を用いた海洋表面の研究では,アーカイアではなく,ユーバクテリアのみが特定されています.
研究 の 目的:
- 深太平洋の細菌プランクトンにおける微生物の多様性を調査する.
- 海洋環境で以前未知だったアーカイアを特徴づけるために.
- 新しい海洋アーカイアの進化的分岐を探求する.
主な方法:
- 収集されたバイオマスから16SリボソームRNA (rRNA) 遺伝子配列の直接分析.
- 太平洋の100mと500mの深さでバクテリアプランクトンを採取する.
- 系統遺伝的関係を決定するための比較序列分析.
主要な成果:
- 既知の生物と遠い関係にある16S rRNA配列の発見.
- 特定された配列は,動物と植物の間の進化距離に匹敵する進化距離を示した.
- これまでに特徴づけられた生物はどれも,新しい配列と密接に関連していない.
結論:
- この発見は,これまで未知の深海のアルカイア群を示唆している.
- この新しいアーカイア群は,生命の歴史における初期の分岐する系統を代表するかもしれない.
- この研究は,海洋環境における広大で未知の微生物の多様性を強調しています.
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