既存のテルペンサイクラスの構造,メカニズム,および特異性を明らかにするツールとしての祖先の工学
Karen Schriever1,2, Patricia Saenz-Mendez1,2, Reshma Srilakshmi Rudraraju3
1School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH Royal Institute of Technology, 114 28 Stockholm, Sweden.
Journal of the American Chemical Society
|January 26, 2021
まとめ
エンジニアリングされた祖先酵素は,バイオカタリストの設計のための構造的洞察を提供します. スピロビオレン合成酵素のような 既存の酵素に変異を移すことで 製品の特異性が変化しました
科学分野:
- 生物触媒
- タンパク質工学
- 構造生物学
背景:
- テルペンサイクラスは重要な生物触媒であるが,その構造の研究は低配列相似性とタンパク質の不安定性によって妨げられる.
- 酵素のホモロジーモデリングは,配列の類似性とタンパク質の不安定性が限られているため,困難です.
研究 の 目的:
- 酵素工学のためのスピロビオレン合成の構造-活性関係を理解する.
- 祖先の酵素工学と構造的洞察を用いて,テルペンサイクラスの特異性を設計する.
主な方法:
- 熱安定の祖先のテルペンサイクラスの再構築とX線結晶学.
- 構造-活性関係を分析するための分子モデリングと酵素分析.
- 祖先の酵素を設計し 既存の酵素に変異を移す
主要な成果:
- 既存のスピロヴィオレン合成の高信頼性ホモロジーモデルは,エンジニアリングされた祖先テンプレートを使用して生成されました.
- 単一の残留物の交換による祖先の変種は,基板特異性を示し,熱安定性を維持した.
- 2つの変異を祖先の骨組みから既存の酵素に転送することで 特殊性が変化し,スピロビオレンの形成は25倍まで増加した.
結論:
- 酵素工学と組み合わせた 祖先の配列再構築は 生物触媒設計の強力なツールです
- このアプローチにより,信頼性の高いホモロジーモデルを作成し,酵素特異性を設計することができます.
- この研究は,祖先の酵素工学による酵素機能の調整のための成功した戦略を示しています.
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