Resonance Raman Application in Investigations of Cytochrome c Oxidase
Resonance Raman Application in Investigations of Cytochrome c Oxidase
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共振拉曼在细胞色素c氧化酶研究中的应用
DOI：
10.1016/j.bbabio.2011.11.016
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Takashi Ogura
中科院分区：
文献类型：
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作者：
葛谷明紀;橋爪未来;渡邉亮介;南田信哉;大矢裕一;Takashi Ogura
综述了近年来共振拉曼光谱技术在细胞色素C氧化酶研究中的应用。在655 nm处调谐到配体-金属电荷转移吸收带的完全氧化的“隔离”CCO的红光激发RR谱在755 cm−处有一个拉曼光谱，可归属于过氧化氢的νOO伸缩模式。CN-−的结合使RR带减少，同时电荷转移吸收带丢失。这表明，过氧化氢在血红素a3和幼崽之间建立了一座桥梁。整个线粒体的时间分辨RR谱在571 cm−1处发现了一条带，这条带来自Δt=0.4ms、0.6ms和1.4ms的氧化中间体。在−t=0.6ms和1.4ms处，分别观察到P和F中间体的804和780 cmΔ1的谱带。这三个中间体的配位几何构型与所观察到的溶解的CcO各自的物种基本相同。然而，线粒体中氧化中间体的寿命明显长于溶解的CcO的该中间体的寿命。这种现象是由于线粒体基质的pH效应、跨膜的ΔpH和/或ΔΨ的影响，或者是与其他膜成分和/或磷脂相互作用的结果。这篇文章是题为：呼吸氧化酶的特刊的一部分。
Recent applications of resonance Raman (RR) spectroscopy in investigations of cytochrome c oxidase (CcO) are reviewed. Red-excited RR spectra for the fully oxidized “as-isolated” CcO tuned to the ligand-to-metal charge transfer absorption band at 655nm exhibit a Raman band at 755cm−1assignable to the νOOstretching mode of a peroxide. Binding of CN−diminishes the RR band concomitant with the loss of the charge transfer absorption band. This suggests that a peroxide forms a bridge between heme a3and CuB. Time-resolved RR spectroscopy of whole mitochondria identified a band at 571cm−1arising from the oxygenated intermediate at Δt=0.4, 0.6 and 1.4ms. Bands at 804 and 780cm−1of the P and F intermediates were observed at Δt=0.6 and 1.4ms, respectively. The coordination geometries of the three intermediates are essentially the same as the respective species observed for solubilized CcO. However, the lifetime of the oxygenated intermediate in mitochondria was significantly longer than the lifetime of this intermediate determined for solubilized CcO. This phenomenon is due either to the pH effect of mitochondrial matrix, the effect of ΔpH and/or ΔΨ across the membrane, or the effect of interactions with other membrane components and/or phospholipids. This article is part of a Special Issue entitled: Respiratory Oxidases.