De Novo α-ヘリカルバンドルの構造的な風景をナビゲートする

Guto G Rhys¹, Christopher W Wood¹, Joseph L Beesley¹

¹School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , United Kingdom.

Journal of the American Chemical Society

|May 9, 2019

まとめ

研究者は特定のアルファヘリル状のコイル構造を形成する合成ペプチドを設計しましたこれらのペプチドは並列ヘクサマーと反並列テトラーマーを切り替えることができ,新しいタンパク質の工学構造を可能にします.

科学分野:

タンパク質の構造と折りたたみ
合成生物学
バイオ物理学

背景:

アンフィパシーアルファヘリクスは水中で結合してアルファヘリクスの束を形成する.
ハイドロフォビック効果は関連性を誘発するが,ヘリックス数や方向性については特異性がない.
配列と構造の関係は,特定のタンパク質の組み立て,特にアルファヘリクルのコイルを理解するための鍵です.

研究の目的:

シンプルなディマーとトリマーを超えてアルファヘリカルコイルの構造的な風景を調査する.
異なる結合状態を切り替えることができる合成ペプチドシステムを開発する.
タンパク質工学のための安定した反パラレルコイルテトラマーを合理的に設計する.

主な方法:

ペプチド変種の設計と合成
溶液中のペプチド構造の生物物理的手法による特徴づけ
高解像度のX線結晶学で原子構造を決定する.
観察された状態を合理化するために,配列構造関係の分析.

主要な成果:

パラレルヘクサマーと様々なアンチパラレルテトラマーを切り替える合成ペプチド系が開発された.
これらの構造的移行は単一のアミノ酸の変化と溶液条件に敏感である.
高解像度構造はアクセス可能な状態を確認し,その形成の洞察を提供しました.
超安定なアンチパラレルコイルテトラマー (apCC-Tet) が合理的に設計された.

結論:

配列構造の関係を理解することで,アルファ・ヘリカル・コイル・アセンブリを正確に制御できます.
設計されたapCC-Tetは,堅固なデノボのタンパク質の支架を提供します.
この研究はタンパク質工学と合成生物学の応用の可能性を広げています

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