ホースラディッシュペロキシダースは,ヒドロキシウレアから酸化窒素の形成を触媒化した
Jinming Huang1, Erin M Sommers, Daniel B Kim-Shapiro
1Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, USA.
Journal of the American Chemical Society
|March 28, 2002
まとめ
ホースラディッシュペロキシダースは,状細胞貧血と癌の薬であるヒドロキシ尿素から酸化窒素の形成を触媒化する. この反応は過酸化水素を必要とし,ニトロキシルおよび他の化合物を生成し,ヒドロキシウレアの新しいメカニズムを示唆しています.
科学分野:
- バイオケミストリー バイオケミストリー
- 化学生物学 化学生物学とは
- 薬理学 薬理学とは
背景:
- ヒドロキシ尿素は,状細胞貧血および様々な癌の確立された治療法です.
- ヒドロキシ尿素の作用の正確な化学的メカニズムを理解することは,その治療用途を最適化するために不可欠です.
研究 の 目的:
- ハイドロキシウレアから酸化窒素の触媒的生成におけるホースラディッシュペロキシダースの役割を調査する.
- 反応メカニズムを解明し,主要な中間物質と産物を特定する.
主な方法:
- 化学発光および電子パラマグネティック共振 (EPR) スペクトロスコーピー.
- ガス染色体ヘッドスペース分析と赤外線スペクトル検査.
- 吸収スペクトロスコーピーとトラッピング研究.
主要な成果:
- ホースラディッシュペロキシダースは,過酸化水素の存在下で,ヒドロキシウレアから酸化窒素の形成を触媒化する.
- 酸化窒素,二酸化炭素,アンモニア,ニートリート,ニートレートは反応産物として特定されました.
- EPRと捕獲の研究は,窒素酸化基とC-ニトロゾ種の中間性を確認しました.
結論:
- この反応は,ヒドロキシ尿素を,ホースラディッシュペロキシダース化合物IおよびIIによって1電子酸化する.
- ニトロキシルは,ヒースラディッシュペロキシダゼによって生成され,その後,酸化して窒素酸化物になる.
- 放射性中間物質を含む提案されたメカニズムは,観察された製品の分布を説明し,ヒドロキシウレアの薬理学的効果における役割を示唆しています.
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