ヘム/O2/*NO 酸化窒素酸化酸化酵素 (NOD) 反応性:フェノル酸ナトリウムを推定ヘム-ペロキシニート中間体経由で酸化窒素化する
Mark P Schopfer1, Biplab Mondal, Dong-Heon Lee
1Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA.
Journal of the American Chemical Society
|July 25, 2009
まとめ
ヘム-スーパーオクソ複合体は,酸化窒素 (NO) と反応して,酸化窒素酸化酸化酸化窒素酸化酸化酸化窒素を模倣したニトラ酸鉄 (III) 化合物を形成します. このヘム化学は,ペロキシニート中間物質を含み,基質の窒素化につながる可能性があります.
科学分野:
- バイオ・オーガニック化学 バイオ・オーガニック化学
- 酸化化学 オキシデーション化学
- 酸化窒素シグナリング
背景:
- 酸化窒素 (NO) は,様々な生理学的プロセスに関与する重要なシグナル伝達分子です.
- 酸化窒素酸化酸化酸化素酶 (NODs) は,NOを排毒するヘムタンパク質です.
- NOとヘム複合体の反応性を理解することは,生物学的NO代謝の解明に不可欠です.
研究 の 目的:
- ヘム-スーペロキソ複合体の酸化窒素との反応を調査する.
- この反応におけるペロキシニトリート中間物質の潜在的関与を調査する.
- モデルシステムで酸化窒素二酸化炭素酸化酵素酵素の酵素活性を模倣する.
主な方法:
- オーソ-ディフルオロで置換されたテトラアリルポルフィリナートヘム-スーパーオクソ複合体の合成と特徴付け.
- ヘム-スーペロキソ複合体の酸化窒素との反応.
- 反応産物の構造を決定するX線結晶学.
- 2,4-di-tert-butylphenolのような外来基板の存在下での反応の調査.
主要な成果:
- ヘム-スーパーオクソ複合体は,酸化窒素と反応して,ニトラ酸鉄 (III) 化合物を生成した.
- ペロキシニトリート中間物質が反応経路に関与していた.
- 2,4-di-tert-butylphenolの存在下では,フェノルのo-ニート化が発生し,2,4-di-tert-butyl-6-nitrophenolが得られました.
- 鉄の最終製品は,ヒドロキソ鉄 (III) 種として特定されました.
結論:
- ヘム/O(2)/NOの化学反応は,NODの活性を模倣したニートラート-鉄(III) 種の形成につながる可能性があります.
- ペロキシニトリート中間物質が関与し,外部基質に酸化性および窒素性損傷を引き起こす可能性があります.
- このモデルシステムは,ヘムタンパク質と酸化窒素との複雑な反応性についての洞察を提供します.
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