19 F HIV-1 カプシドタンパク質アセンブリのNMR用高速マジックアングル回転によるダイナミック核極化
Manman Lu1,2,3, Mingzhang Wang1,2, Ivan V Sergeyev4
1Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States.
Journal of the American Chemical Society
|March 16, 2019
まとめ
ダイナミック・ニュークレア・ポラライゼーション (DNP) は,HIV-1カプシドタンパク質アセンブリに対する19Fマジック・アングル・スピニング (MAS) NMRの感受性を有意に高めます. 生物分子の構造を 詳細に分析できるようになりました
科学分野:
- バイオ物理学
- 構造生物学
- 核磁気共鳴スペクトル
背景:
- HIV-1 カプシドタンパク質 (CA) アセンブリは,ウイルスの構造と機能に不可欠です.
- HIV-1 CAのような大きな生物分子の構造を決定することは,従来のNMRでは困難です.
- F NMRは生物分子の研究にユニークな利点をもたらしますが,感度が制限される可能性があります.
研究 の 目的:
- HIV-1 CA アセンブリにおける信号感度を高めるための 19F ダイナミック・ニュクリア・ポラライゼーション (DNP) マジック・アングル・スピニング (MAS) NMR の有用性を調査する.
- 長期的な構造情報を得るためのDNP強化F MAS NMRの可能性を調査する.
- 信号強化を最大化するためにDNPパラメータを体系的に最適化します.
主な方法:
- 19F ダイナミックな核極化 (DNP) マジック・アングル・スピニング (MAS) NMRスペクトロシー 14.1 T
- 20 kHz以上のMAS周波数で2D19F-13C HETCORスペクトルの取得
- DNP強化の体系的な定量化により,バイラジカル濃度,MAS周波数,温度,およびマイクロ波出力が変化する.
主要な成果:
- HIV-1 CAアセンブリのF DNP MASスペクトルで最大100倍の信号強化を達成した.
- 観測された絶対感度比は12−29であり,H信号と比較できる.
- 記録された2D19F-13C HETCORスペクトルは,長距離の分子内および分子間相関を明らかにしています.
- 異なる実験条件下でのDNP増強因子に関する体系的なデータを提供した.
結論:
- DNP強化のF MAS NMRは,HIV-1 CAアセンブリに対して顕著な感度改善をもたらします.
- この技術は,タンパク質構造の決定のためのユニークな長距離制限を生成します.
- このアプローチは,多様な大型生物分子システムの構造的特徴化に非常に有望である.
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