DNA/RNAポリメラーゼによって触媒化された核酸ポリメリゼーションの自己活性化メカニズム
Vito Genna1,2, Pietro Vidossich2, Emiliano Ippoliti2
1Laboratory of Molecular Modeling & Drug Discovery, Istituto Italiano di Tecnologia , Via Morego 30, 16163, Genoa, Italy.
Journal of the American Chemical Society
|August 18, 2016
まとめ
DNA/RNAポリメラーゼは,新しい自己活性化メカニズム (SAM) を用いて遺伝を継承する. このメカニズムは,以前の仮説とは異なる,効率的なヌクレオチド添加とDNA/RNA転位を可能にする重要なH結合を含んでいる.
科学分野:
- 生物化学
- 分子生物学
- 遺伝学
背景:
- DNA/RNAポリメラーゼ (Pol) によるDNAとRNAの酵素的ポリメリゼーションは遺伝的遺伝に不可欠である.
- 現存するPol触媒のモデルは,基板結合,核酸添加,および転位の効率と調整を完全に説明できません.
研究 の 目的:
- ポリメラーゼのミカエリス複合体における以前に認識されていないH結合相互作用を解明する.
- ポリメラーゼ触媒のための新しい自己活性化メカニズム (SAM) を提案し,検証する.
主な方法:
- 保存された相互作用を特定するためのバイオ情報分析.
- Ab initio 量子力学/分子力学 (QM/MM) ヒトDNAポリメラーゼ-ηのシミュレーション
主要な成果:
- マイケリス複合体では,入ってくるヌクレオチドの3'-OHとβ-フォスファートの間の保存されたH結合が確認された.
- 特定されたH結合は,核愛者の形成,核酸添加,および転位を統合する新しい自己活性化メカニズム (SAM) をサポートする.
- QM/MMシミュレーションは,ヒトDNAポリメラーゼ-ηの提案されたSAMを裏付けました.
結論:
- 新しい自己活性化メカニズム (SAM) は,以前の仮説とは異なる,ポリメラーゼ触媒の優雅で効率的なモデルを提供します.
- DNAとRNAポリメラーゼの構造的な保存は,SAMが生命の3つの領域における普遍的なメカニズムである可能性があることを示唆しています.
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