ヘムモデルによって媒介された窒素の減少. NOとHNOへのルート
Julie L Heinecke1, Chosu Khin, Jose Clayston Melo Pereira
1Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106-9510, USA.
Journal of the American Chemical Society
|February 21, 2013
まとめ
水溶性フェリヘムモデルは,窒素から様々な分子への酸素の転送を容易にする. このプロセスは,活性鉄の種を再生し,窒素酸化物 (NO) と窒素酸化物 (HNO) を形成し,窒素酸塩に関連しています.
科学分野:
- バイオケミストリー バイオケミストリー
- 無機化学 無機化学とは
- 薬用化学 薬用化学について
背景:
- 無機ニトリットは,イシュケミア/再注射 (I/R) 損傷において保護的役割を果たします.
- 酸化窒素 (NO) の形成は,窒素酸塩の保護効果を支える重要なメカニズムです.
- 窒素酸塩の酸化還元化学を理解することは,治療用途において極めて重要です.
研究 の 目的:
- 水溶性フェリヘムモデルの酸素原子移転機構を調査する.
- ニートリートからNOとニトロキシル (HNO) の形成経路を解明する.
- I/R損傷におけるニトリートの保護作用に対するこれらの酸化還元変異の関連性を調査する.
主な方法:
- 水溶性フェリヘムモデル,Fe (III) (TPPS) を使った.
- フォスフィンや生物学的チオール (システイン,グルタチオン) を含む様々な還元剤との反応を研究した.
- 電気化学センサーとトラッピング実験を用いて,反応性中間物質を特定した.
主要な成果:
- Fe (III) (TPPS) を媒介する酸素原子の移転により,窒素からフォスフィン,チオールへと変化する.
- スルフェン酸はチオールから形成されたが,チオール余量に素早く反応した.
- レドックス変換によりFe (III) (TPPS) が再生され,N2O,NO,HNOが形成された.
結論:
- フェリヘムモデルは,窒素由来酸素原子の移転と酸化還元サイクルを容易にする.
- HNOは,N2O形成における重要な中間物質として特定されています.
- 研究されたメカニズムは,I/R損傷時の窒素の保護効果についての洞察を提供します.
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