シトラート合成の可逆性により,熱性細菌の自己栄養的成長が可能である
Achim Mall1,2, Jessica Sobotta3, Claudia Huber3
1Mikrobiologie, Fakultät für Biologie, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany.
Science (New York, N.Y.)
|February 9, 2018
まとめ
この研究は,新しいエネルギー効率の良い自己栄養的な炭素固定経路を,Desulfurella acetivorans*で明らかにした. 主要な酵素が欠けているこの見過ごされた経路は プライマリ生産の現在の生物情報学的な予測に 挑戦しています
科学分野:
- 微生物生態学
- 生物化学
- 代謝経路
背景:
- 生物学的無機炭素の固定は,一次生産に不可欠であり,様々な自己栄養経路を経由して発生する.
- メタゲノムにおける重要な酵素遺伝子を特定することは,炭素固定への微生物の貢献を評価するための標準です.
- トリカルボキシル酸 (TCA) 循環の方向性は,炭素代謝を理解するために重要である.
研究 の 目的:
- 硫黄を減少させるバクテリアの自己栄養能力を調査する.
- 自動栄養状態下でのD.アセチボランスの炭素代謝におけるトリカルボキシル酸循環の役割を特徴付ける.
- 標準的なゲノム解析で見逃されるかもしれない新しい炭素固定経路を特定する.
主な方法:
- オートロフィック条件下での"Desulfurella acetivorans"の栽培
- トリカルボキシル酸サイクル活動に焦点を当てた代謝分析
- サイトレート合成を含む主要な酵素の機能を決定する酵素分析.
主要な成果:
- *デスルフレラ・アセチボランス*は,還元性TCAサイクルを使用して,自己栄養的な炭素固定を行います.
- サイトレート合成酵素は,アデノシン三リン酸から独立して,自己栄養状態でサイトレートをアセチル共酵素Aとオクサロアセタートに分解することが示された.
- この経路はエネルギー効率が高くても 標準的な鍵となる酵素が欠けていて ゲノムによる検出が困難です
結論:
- 新しい,エネルギー効率の良いオートトロフィック炭素固定経路は,D.アセトボランスに存在する.
- この経路は,微生物の炭素固定を予測するための鍵となる酵素検出への依存に挑戦しています.
- このような経路の存在は,世界の一次生産の評価のための生物情報学的アプローチの再評価を必要とします.
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