サイトクローム・C・ニトリット・リダクタゼの構造
O Einsle1, A Messerschmidt, P Stach
1Max-Planck-Institut für Biochemie, Abteilung Strukturforschung, Martinsried, Germany. einsle@biochem.mpg.de
Nature
|August 10, 1999
まとめ
サイトクロームc窒素還元酵素の結晶構造が決定され,生物学的窒素循環におけるその役割が明らかになった. この酵素は,窒素をアンモニアに還元することを促進し,無酸素エネルギー代謝に不可欠です.
科学分野:
- バイオケミストリー バイオケミストリー
- 微生物学 微生物学とは
- 構造生物学 構造生物学とは
背景:
- サイトクロームc窒素還元酵素は,生物学的窒素循環に不可欠であり,窒素をアンモニアへの変換を触媒化する.
- ディシミレータ性窒素アンモニー化の無酸素エネルギー代謝において重要な役割を果たします.
研究 の 目的:
- Sulfurospirillum deleyianumからサイトクロームcニート還元酵素の結晶構造を決定する.
- 酵素の反応機構と活性部位を解明する.
- 同様のヘム配列を持つ保存されたタンパク質ファミリーを識別する.
主な方法:
- X線結晶グラフィーです.
- 多波長異常分散 (MAD) 方法について
- スペクトロスコピク分析
主要な成果:
- サイトクロームcナイトリート還元酵素の結晶構造が解け,機能的二酸化物を明らかにした.
- この酵素には10のc型ヘム群と,活性部位に異常なライシン調整の高スピンヘム群が含まれています.
- 構造的およびスペクトル学的データに基づいて,窒素変異の反応スキームが提案されました.
結論:
- 決定された構造は,窒素還元の触媒機構の洞察を提供します.
- 保存されたヘム指向が保たれているが,構造と機能が変動するマルチヘム細胞染色体の保存された家族が特定されました.
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