世界的に重要な海洋ダイアゾトロフトライコデスミウム (Trichodesmium) による酸塩の利用
S T Dyhrman1, P D Chappell, S T Haley
1Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA.
Nature
|January 7, 2006
まとめ
海洋サイアノバクテリア・トリコデスミウム (Trichodesmium) は,有機リン化合物,特にリン酸塩が不足しているときにリン酸塩化合物を利用することができます. このユニークな適応は,栄養素が少ない海洋地域での彼らの流行を説明するのに役立ちます.
科学分野:
- マリン・マイクロバイオロジー
- バイオジオケミカルサイクルとは
- 分子生物学は分子生物学である.
背景:
- トリコデスミウムのような海洋ダイアゾトロフは,世界の炭素と窒素の循環に不可欠です.
- 海洋の渦巻はしばしば低濃度のリン酸を含み,植物プランクトンの増殖を制限する.
- 溶解した有機リンは,大きく,未充分に利用された栄養素のプールを表します.
研究 の 目的:
- トライコデスミウム・エリトレイウムのストレスに対する生理学的反応を調査する.
- 有機リン化合物の吸収と利用に関与する遺伝子を特定する.
- トライコデスミウムのオリゴトロフな海洋環境への適応を理解するために.
主な方法:
- トリコデスミウムエリトレイウム IMS101.1.のゲノム解析
- フォスフォナート代謝に関連する遺伝子の誘導は,のストレス下で行われます.
- サルガソ海のT. erythraeum集団における遺伝子発現分析.
主要な成果:
- リンストレスが,炭素-リン溶解経路経由で高親和性リン酸体輸送と水解のための遺伝子を誘導する.
- これらの遺伝子は,サルガソ海のT. erythraeumで活発に発現しています.
- トリコデスミウムは,海洋サイアノバクテリアの中で,有機源からリンを採取するユニークな能力を有しています.
結論:
- トリコデスミウムは,オリゴトロフィックな海における,以前は認識されなかった,の源である,フォスフォナートを利用することができる.
- 炭素-リン酸リアース経路は,低リン酸環境でトリコデスミウムに競争上の優位性を提供します.
- この適応が,栄養が限られた海洋生態系におけるトリコデスミウムの成功を説明している可能性が高い.
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