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Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
窒素性ストレス下におけるサイクロオキシゲネーゼ不活性化を防ぐための基板結合の物理的証拠
Ruba S Deeb1, Cynthia Cheung, Tal Nuriel
1Department of Pathology, Weill Cornell Medical College of Cornell University, 1300 York Avenue, New York, New York 10065, USA. rsdeeb@med.cornell.edu
Journal of the American Chemical Society
|March 4, 2010
まとめ
基板への結合は,サイクルオキシゲネーゼ-1 (COX-1) を反応性窒素種による無活性化から保護する. この発見は,酸化ストレス中のCOX-1活性に対する新しい保護機構を明らかにしています.
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
- 分子生物学は分子生物学である.
背景:
- サイクロオキシゲナーゼ (COX) 酵素は,異なる活性部位を介してプロスタグランディンのバイオシンセシスを触媒化する.
- COX酵素の調節と機能は完全に理解されていません.
- 酸化ストレスは,COX酵素を改変する反応性窒素種を生成し,前列腺素の産生を変化させます.
研究 の 目的:
- 窒素酸性無活性化に対するサイクロオキシゲナーゼ-1 (COX-1) の保護機構を調査する.
- 反応性窒素種によるCOX-1調節における基板占有率の役割を決定する.
主な方法:
- サイト・ディレクテッド・ミュータゲネシス (サイト・ディレクテッド・ミュータゲネシス) により,重要なチロシン残基を特定する.
- 酵素動力学アッセイは,COX-1の活動を測定するものです.
- タンパク質の改変を確認するための質量スペクトロメトリ.
主要な成果:
- COX-1は,Tyr385で選択的窒素化され,触媒不活性化につながります.
- COX-1活性部位への基質結合により,Tyr385の窒素化が防止されます.
- 活性部位が基板に占められるとき,窒素は他のチロシン残基に誘導され,酵素の活性が保存されます.
結論:
- 基板の占有量は,COX-1を窒素性無活性化から保護する重要な要因です.
- この研究では,酸化ストレスを含む病理生理学的状態におけるCOX-1の調節と保護のための新しいメカニズムを発見しました.
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