T7 RNAポリメラーゼのトランスクリプションは,5位変形UTP誘導体によるものです
Jonathan D Vaught1, Torin Dewey, Bruce E Eaton
1College of Physical and Mathematical Sciences, Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
Journal of the American Chemical Society
|September 10, 2004
まとめ
改変ウリジン三リン酸 (UTP) デリバティブは,T7 RNAポリメラーゼ (T7 RNAP) の転写を効率的にサポートし,完全な長さの転写を生成します. 動力学的研究は,水害性UTPの改変が転写動力学を大幅に変化させないことを明らかにし,充電された改変は基板親和の要件を増加させる.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 合成化学 合成化学とは
背景:
- 無修正ウリジン三リン酸 (UTP) は,RNA合成の基本的な基質である.
- UTPの修正は,その性質とRNAへの組み込みを変化させる可能性があります.
- T7RNAポリメラーゼ (T7RNAP) は,in vitroトランスクリプションで広く使用されている酵素です.
研究 の 目的:
- T7 RNAPトランスクリプションの基質として,アミド結合によって5位で修正された7つのUTP誘導体を評価する.
- これらの改変が転写収量と運動学に与える影響を評価する.
- 改変塩基がRNAの延長を阻害するかどうかを判断する.
主な方法:
- 様々な5位アミド変異を持つ7つのUTP誘導体の合成.
- トランスクリプションアッセイは,T7 RNAPと,様々なDNAテンプレートを持つ改変UTP基板を用いて行われます.
- 変更されたUTPsでT7RNAPのマイケリス定数 (K(m)) と最大速度 (V(max)) を決定するための運動分析.
主要な成果:
- すべての7つのUTP誘導体は,挑戦的なDNAテンプレートでも,十分な量の全長トランスクリプトを生成しました.
- ハイドロフォビック5位変異 (フェニル,ピリジル,インドリル,イソブチル) は,K (m) とV (max) の値が,未修正のUTPに匹敵することを示した.
- 5位におけるイミダゾールとアミノの改変により,K (m) の値が著しく上昇した.
- テストされたすべてのUTP誘導体は,RNAの延長を妨げることなく,トランスクリプトに組み込まれました (類似のV(max)).
結論:
- 排水性5位変異を持つ5つのUTP誘導体は,T7RNAP転写のための効率的な基板である.
- プラスの電荷を持つ5位変異は,酵素の基質親和度要件を高めます.
- UTPの5位変異は,T7RNAPによるRNAトランスクリプトの延長を本質的に阻害しない.
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