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Updated: Jun 26, 2026

08:57
Aip1p Dynamics Are Altered by the R256H Mutation in Actin
Published on: July 30, 2014
結晶構造によって明らかにされたYopH変異体におけるタンパク質ループヒンジーの残留物の変異による酸触媒の障害
Tiago A S Brandão1, Howard Robinson, Sean J Johnson
1Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, USA.
Journal of the American Chemical Society
|January 15, 2009
まとめ
Yersiniaタンパク質-チロシンフォスファタゼ (YopH) のキーヒンジ残基の変異は,触媒作用を阻害する. 構造研究は,半閉じたWPDループを明らかにし,酵素活性低下を説明し,新しいdivanadate種を特定します.
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:
- Yersinia protein-tyrosine phosphatase (YopH) は,バクテリアの毒性にとって極めて重要です.
- YopHに保存されたTrp354残留は,触媒に不可欠な柔軟なWPDループのヒンドル残留です.
- Trp354からPhe (W354F) に変異すると,YopHの触媒活性が著しく低下する.
研究 の 目的:
- YopH.におけるW354F変異によって引き起こされる触媒的障害の構造的基礎を解明する.
- YopH触媒におけるWPDループ構成の役割を調査する.
- YopHとオキシアニオンの相互作用を特徴付けるために.
主な方法:
- W354F YopH.の高解像度結晶構造の決定について
- トングステートとバナデートの存在と不在のX線結晶学.
- 酵素-阻害剤の相互作用とループ構成の分析.
主要な成果:
- W354F YopHのPループへのオキシアニオン結合は,ネイティブ酵素に類似しています.
- W354F YopH の WPD ループは,ネイティブ YopH の完全に閉じた状態とは異なり,オキシアニオンと半閉じた形状を採用しています.
- 1.4 Å の構造は,W354F YopH. YopH. に結合した前例のないサイクルディヴァナダート種を明らかにしました.
結論:
- W354F YopHにおけるWPDループの閉塞が損なわれることが,一般の酸性触媒の減少を説明する.
- YopHの機能とヒンジの残留変異の影響に関する構造的洞察.
- タンパク質の結晶構造における新しいディヴァナダート種の発見.
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