Time resolved infrared spectroscopy of cytochrome c oxidase in aqueous solution

以fs红外激光器为光源，建立了时间分辨红外系统，研究了细胞色素c氧化酶（C_cO）的质子抽运机制。用该系统对H_2O溶液中的C_cO进行了分析，研究了以CO作为O_2模拟物的O_2还原位点的功能。结果表明，存在一个构象中继系统，它在连接CuB位点和水通道以有效收集被泵送的质子方面起着关键作用。结果表明，在Fe_<a3>-CO光解后，co与Cu_B的瞬时结合打开了水通道。

The newly developed time-resolved infrared system was constructed using fs infrared laser for a light source to investigate a proton pumping mechanism of cytochrome c oxidase(C_cO). The function of the O_2 reduction site using CO as an analogue of O_2 was investigated by this new system which is capable of analyzing C_cO in H_2O solution. The results indicate the existence of a conformational relay system which plays a key role in connecting the CuB site and the water channel for efficient collection of protons being pumped. It was found that transient CO-binding to Cu_B, after Fe_<a3>-CO photolysis, opens the water-channel.