果糖1,6-ビスホスファートアルドラーゼ/フォスファターゼは,祖先のグルコネオゲン系酵素である可能性がある
1Mikrobiologie, Fakultät Biologie, Universität Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany.
Nature
|March 30, 2010
まとめ
ほとんどのアルカイアとバクテリアは,二重の果糖1,6-ビスホスファート (FBP) アルドラーゼとFBP フォスファターゼ活性を持つ熱に安定した酵素を持っています. この二機能酵素は,熱好きの生物の片方向性グルコネオゲネシスに不可欠であり,それが示唆されています.
科学分野:
- バイオケミストリー バイオケミストリー
- 進化生物学の進化生物学について
- 微生物学 微生物学とは
背景:
- 熱好きの生物は,古生物や深分岐細菌に多く見られ,高温で,しばしば無酸素の環境で,化学的自己栄養代謝を利用する.
- これらの生物は二酸化炭素を固定してアセチル共酵素Aを生成し,これはグルコネオゲネシスの出発点である.
研究 の 目的:
- 熱愛性アーカイアとバクテリアにおける果糖1,6-ビスホスファート (FBP) アルドラーゼ/フォスファターゼの存在と機能を調査する.
- これらの生物のグルコネオゲネシス経路におけるこの酵素の役割を明らかにする.
主な方法:
- 酵素活性アッセイは,二機能果糖1,6-ビスホスファート (FBP) のアルドラーゼ/フォスファタゼ活性を決定する.
- 考古学,バクテリア,ユーカリオット系における酵素存在の比較分析.
- 酵素の熱安定性を評価する.
主要な成果:
- 保存された,二機能のFBPアルドラーゼ/フォスファタゼは,事実上すべての古生物群と深く分岐する細菌系統で特定されました.
- この酵素はFBPアルドラーゼとFBPフォスファタゼの両方の活性を示し,熱に安定しています.
- 酵素の二機能性により,熱反応性トライアソフォスファートの迅速な処理により,片方向性グルコネオゲネシスを促進する.
結論:
- 特定された二機能FBPアルドラーゼ/フォスファタゼは,ペースメーカーの祖先のグルコネオゲン酵素として提案されています.
- この発見は,グルコネオゲネシスがグリコリシスより前に進化したことを示唆している.
- この酵素の熱安定性は,熱好き微生物の生存と代謝に不可欠です.
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