高圧 ZZ交換 NMR は,タンパク質の折り畳み移行状態の重要な特徴を明らかにする
Yi Zhang1, Soichiro Kitazawa2, Ivan Peran3
1Department of Chemistry & Chemical Biology, Rensselaer Polytechnic Institute , Troy, New York 12180, United States.
Journal of the American Chemical Society
|October 27, 2016
まとめ
ZZ交換 NMRと組み合わせた高圧で,タンパク質の急速な折り畳み速度を測定できます. この技術は,タンパク質ドメインの移行状態の洞察を明らかにし,タンパク質の折り畳みメカニズムを理解するのに役立ちます.
科学分野:
- 生物化学
- バイオ物理学
- 構造生物学
背景:
- 塩基配列依存性を理解するには,残基特異のタンパク質の折りたたみと展開速度を決定することが重要です.
- 従来のNMR方法は多くのタンパク質の折りたたみ反応に遅すぎます.
- 高気圧はタンパク質の折り畳みを著しく遅らせ,運動研究に役立ちます.
研究 の 目的:
- タンパク質の急速な折りたたみ運動を測定するために,高圧乱射とZZ交換NMRスペクトロスコピーを組み合わせた方法を開発し,適用する.
- 2つのタンパク質ドメイン (NTL9とCTL9) の折り畳みメカニズムと移行状態特性を調査する.
主な方法:
- 高い水圧と組み合わせたZZ交換NMRスペクトロスコーピーを利用した.
- L9タンパク質ドメイン (NTL9とCTL9) の折り畳み速度を遅らせるための圧力乱射.
- 高圧 (2500 bar) と大気圧で残留物特有の表面的な折り畳みと開く速度が得られる.
主要な成果:
- NTL9の折り畳みはほぼ2つの状態の行動を示し,CTL9はわずかな偏差を示した.
- NTL9とCTL9は,折りたたむための大きなポジティブアクティベーションボリュームを示しました.
- 両ドメインの移行状態は,その本来の状態に類似した,有意な溶媒を除外された空隙を含んでいることが判明した.
結論:
- 高圧とZZ交換NMRスペクトロスコピーの結合により,より広い範囲のタンパク質構成変異に適用できます.
- 容積特性は,タンパク質の移行状態がコンパクトであり,原生水性核の特徴を保持することを示唆している.
- この方法は,タンパク質の折りたたみに関する研究のために,残留物特有の有価な動力学および熱力学データを提供します.
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