化学兵器VXの酵素による中和:フォスフォートリエステラゼの進化により,フォスフォートチオラート溶解液の水解化が行われる
Andrew N Bigley1, Chengfu Xu, Terry J Henderson
1Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842, United States.
Journal of the American Chemical Society
|June 25, 2013
まとめ
研究者は,VX.のようなV型神経毒に対する触媒活性を強化するために,フォスフォートリエステラゼ (PTE) 酵素の変種を設計しました. 最高の変異体は,VXを水解する230倍の改善を示し,有望な汚染除去戦略を提供しました.
科学分野:
- バイオケミストリー バイオケミストリー
- 酵素学 酵素学とは
- 化学工学は化学工学というものです.
背景:
- V型神経毒物質 (VXとVR) は高度に毒性があり,持続性があり,効果的な浄化方法が必要です.
- 野生型フォスフォートリエステラーゼ (PTE) はVXを水分解するが,他の基板と比較して効率が低い.
- PTEの活性部位の残留物は,誘導進化によって,触媒活性を改善するために操作することができます.
研究 の 目的:
- V型神経毒剤に対する触媒活性を改善した新しいPTE変種を設計する.
- 酵素改善のための指向進化と誤りやすいPCRの有効性を調査する.
- VXの浄化のための強化された触媒を開発する.
主な方法:
- 連続した2箇所の変異ライブラリが作成され,PTEの12箇所のアクティブサイト残留物をターゲットにしました.
- 図書館は,VXのアナログであるDEVX.に対して,触媒活性についてスクリーニングされました.
- さらに最適化するために,ループ-7のターゲッテッドエラー傾向PCRミュータゲネシスを使用した.
主要な成果:
- 進化したPTE変種は,野生型と比較してDEVX水解の26倍強化を示しました.
- 更に進行した突然変異により,DEVXの水解速度が78倍まで増加した変種が生まれた.
- 最良の変異体はVX水解の230倍改善 (kcat/Km = 7 × 10(4) M(-1) s(-1)) を示し,売上高の152倍増加を示した.
結論:
- エンジニアリングされたPTE変種は,VX神経毒に対する触媒活性が著しく強化されていることを示しています.
- これらの改善されたPTE変異体は,VXの水解のために報告された最も効果的な触媒を表しています.
- この研究は,強力な酵素ベースの除染剤の開発のための指向進化戦略を検証しています.
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