Oxygen activation and reduction in respiration: Involvement of redox-active tyrosine 244
Oxygen activation and reduction in respiration: Involvement of redox-active tyrosine 244
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DOI：
10.1126/science.290.5496.1588
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发表时间：
2000-11-24
期刊：
影响因子：
56.9
通讯作者：
Babcock, GT
中科院分区：
文献类型：
--
作者：
Proshlyakov, DA;Pressler, MA;Babcock, GT
细胞色素氧化酶激活 O-2 并将其还原为水以维持呼吸，并利用释放的能量驱动质子易位和 5'-三磷酸腺苷合成。该过程中的一个关键中间体 P 位于 O-2 还原和质子泵功能的交界处。我们使用放射性碘标记，然后进行肽图分析，以深入了解 P 的结构。我们表明，交联的组氨酸 240-酪氨酸 244 (His(240)-Tyr(244) 物种在 P 形成中具有氧化还原活性，从而建立了其结构为 Fe-IV=O/(CuB2+H240)-Y-244。因此，从 O-2 到蛋白质部分的能量转移被用作一种策略避免有毒中间体并控制随后的质子泵浦事件中的能量利用。
Cytochrome oxidase activates and reduces O-2 to water to sustain respiration and uses the energy released to drive proton translocation and adenosine 5'-triphosphate synthesis. A key intermediate in this process, P, lies at the junction of the O-2-reducing and proton-pumping functions. We used radioactive iodide labeling followed by peptide mapping to gain insight into the structure of P. We show that the cross-linked histidine 240-tyrosine 244 (His(240)-Tyr(244) species is redox active in P formation, which establishes its structure as Fe-IV=O/(CuB2+H240)-Y-244. Thus, energy transfer from O-2 to the protein moiety is used as a strategy to avoid toxic intermediates and to control energy utilization in subsequent proton-pumping events.