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非ヘム鉄部位におけるペロキシ介質の核共振振光譜的定義

Kyle D Sutherlin¹, Lei V Liu¹, Yong-Min Lee²

¹Department of Chemistry, Stanford University , Stanford, California 94305, United States.

Journal of the American Chemical Society

|October 12, 2016

まとめ

核共鳴振動スペクトル検査 (NRVS) は,生物修復酵素における鉄 (Fe) 中間物質の重要な振動データを明らかにする. この研究は,これらの重要なFe-ペロキシ種の構造を決定するスペクトロスコピックマーカーを定義します.

科学分野:

生物化学
生物物理化学
コンピュータ化学

背景:

単核非ヘム鉄酵素は生物修復に不可欠である.
これらの酵素のFe (III) -ペロキシ中間体は,限られた振動データのために,構造とプロトネーション状態が定義されていない.

研究の目的:

核共振振動スペクトロスコーピー (NRVS) を利用してFe (III) -ペロキシ中間物質を特徴付ける.
密度関数理論 (DFT) の計算を使用してNRVSスペクトルを割り当てます.
これらの中間物質の結合モードとプロトネーション状態を決定するためのスペクトル学的なサインを特定する.

主な方法:

横のFe ((III)) -ペロキシおよび端のFe ((III)) -ヒドロペロキシモデル複合体のNRVSスペクトルの取得と分析.
スペクトル割り当てのためのDFT計算の校正.
NRVSスペクトルのプロトネーションとFe-O-O角度の影響の計算調査.

主要な成果:

モデルFe ((III)) -ペロキシ複合体のNRVSスペクトルの割り当てに成功しました.
構造的変異と相関する4つの異なるスペクトル学的特徴 (ハンドル) の識別.
陽子とFe-O-Oの角度の変化がNRVSスペクトルにどのように影響するかを示す.

結論:

NRVSは,DFTと組み合わせて,非ヘム鉄酵素におけるFe (III) -ペロキシ中間物の構造を明らかにする強力な方法を提供します.
特定された光学ハンドルは,過酸化物の結合モードとプロトネーション状態の正確な決定を可能にします.
これらの構造的特徴を理解することは,バイオリメディエーションにおける酵素の反応性と機能の予測に不可欠です.

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