ニートリート還元酵素における2型銅に対するサイドオンNO調整のモデリング:構造,エネルギー,結合
Ingar H Wasbotten1, Abhik Ghosh
1Department of Chemistry, University of Tromsø, N-9037 Tromsø, Norway.
Journal of the American Chemical Society
|November 3, 2005
まとめ
密度関数理論 (DFT) の計算により,ニートリート還元酵素 (CuNIR) で新しい銅-ニトロシル種 ({CuNO}10と{CuNO}11) が特定されました. {CuNO}11の種は,CuNIRの活性部位に好ましいエネルギーと幾何学を示しています.
科学分野:
- バイオケミストリー バイオケミストリー
- コンピューティング・ケミストリー
- 酵素のメカニズム
背景:
- ニトリート還元酵素 (NiR) は,窒素循環において極めて重要です.
- 2型銅部位はNiRの酵素活性に関与しています.
- 銅-ニトロシル種の協調化学を理解することは,NiR機構の解明に不可欠です.
研究 の 目的:
- メタステーブルな銅-ニトロシル種の存在と性質を調査する.
- ニトロシル (NO) と銅のNiRにおける好ましい調整モードを決定する.
- CuNIR中間物質の実験的な結晶学データと計算モデルを比較する.
主な方法:
- 密度関数理論 (DFT) の計算が採用されました.
- メタスタブルな{CuNO}10種と{CuNO}11種をモデル化した.
- エネルギー優位性と幾何学的なパラメータを分析した.
主要な成果:
- DFTの計算は,サイドオン{CuNO}10と{CuNO}11種の存在を確認した.
- {CuNO}11の種は,NOの協調により有利なエネルギーを示しています.
- {CuNO}11の幾何学的なパラメータは,CuNIR中間物質の結晶学的データとよりよく一致しています.
結論:
- メタスタブルな{CuNO}10と{CuNO}11の種は,CuNIRの2型銅部位に関連しています.
- サイドオンNOの調整は,{CuNO}11種にとってエネルギー的に好ましい.
- {CuNO}11は,{CuNO}10.と比較して,CuNIR中間物質のより良い構造モデルを提供します.
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