アミノアシル-tRNAタンパク質トランスファーゼによるタンパク質ベースのペプチド結合形成
Kazunori Watanabe1, Yukimatsu Toh, Kyoko Suto
1Institute of Biological Resources and Functions, National Institute of Advanced Industrial Sciences and Technology, 1-1-1, Higashi, Tsukuba-shi, Ibaraki 305-8566, Japan.
Nature
|September 25, 2007
まとめ
ユーバクテリアのルシル/フェニララニル-tRNAタンパク質トランスファーゼ (LF-トランスファーゼ) は,新しいタンパク質ベースのメカニズムを使用してペプチド結合を形成します. 電子リレーシステムは,陽子の抽象を容易にし,ペプチド結合形成のための核愛性の攻撃を可能にします.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- 酵素学 酵素学とは
背景:
- ユーバクテリアのルシル/フェニララニル-tRNAタンパク質転送酶 (LF-トランスファーゼ) はペプチド結合形成を触媒化する.
- LF-トランスフェラーゼの正確な触媒メカニズムは,ほとんど知られていなかった.
研究 の 目的:
- LF-トランスファーゼによるペプチド結合形成の触媒的メカニズムを解明する.
- LF-トランスフェラーゼ活動の構造的基礎を決定する.
主な方法:
- 複雑な構造を特定するためのX線結晶学.
- 触媒作用を調査するためのサイト・ディレクテッド・ミュータゲネシス研究.
主要な成果:
- LF-トランスフェラーゼ複合体の構造を基質とペプチドアナログで決定した.
- Asp 186 と Gln 188 を含む電子リレーが特定されました.
- このリレーは,受容体ペプチドのN末端Arg.から陽子の抽出を促進します.
結論:
- LF-トランスフェラーゼは,セリンプロテアゼアサイレーションの逆に似たタンパク質ベースの触媒メカニズムを使用しています.
- 特定されたメカニズムは,LF-トランスフェラーゼがペプチド結合形成のためのヌクレオフィルを生成する方法を説明します.
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