フタル酸二酸化炭素酵素還元酵素:ピリジンヌクレオチドから [2Fe-2S] への電子移転のためのモジュール構造
C C Correll1, C J Batie, D P Ballou
1Department of Biological Chemistry and Biophysics, University of Michigan, Ann Arbor 48109.
まとめ
鉄硫黄のフラボタンパク質であるフタル酸二酸化酸化酵素還元酵素 (PDR) は,フラビンモノヌクレオチド (FMN) を電子移転に使用しています. その結晶構造は,このプロセスにおける重要な相互作用を明らかにします.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- 酵素学 酵素学とは
背景:
- フタル酸二酸化酸化酵素還元酵素 (PDR) は,電子伝送に不可欠な鉄硫黄のフラボタンパク質です.
- コファクターとしてフラビンモノヌクレオチド (FMN) を利用しています.
研究 の 目的:
- Pseudomonas cepacia.からPDRの結晶構造を決定するために.
- PDRによって媒介される電子移転の構造的基礎を分析する.
主な方法:
- 酸化および還元されたPDR.のX線結晶学.
- PDR複合体のNADHとピリジンヌクレオチドの分析.
主要な成果:
- 結晶構造は2.0と2.7アングストームの解像度で決定された.
- NADH,FMN,および [2Fe-2S] クラスターは,中央の裂け目の近くの異なる領域に位置しています.
- フラビンと [2Fe-2S] クラスタの間の近距離 (4.9 アングストーム).
結論:
- PDR構造は,NADHから [2Fe-2S] クラスタへの効率的な電子転送を促進します.
- [2Fe-2S]クラスタの結合部位は植物性フェルドキシンに似ていますが,高酸化還元能力があります.
- PDRは,フェレドキシンNADP(+) - 還元酵素に関連したフラボタンパク質還元酵素の独特な家族に属しています.
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