Dynamic interactions of CO with a3Fe and CuB in cytochrome c oxidase in beef heart mitochondria studied by Fourier transform infrared spectroscopy at low temperatures.
Dynamic interactions of CO with a3Fe and CuB in cytochrome c oxidase in beef heart mitochondria studied by Fourier transform infrared spectroscopy at low temperatures.
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低温下傅里叶变换红外光谱研究牛心线粒体细胞色素c氧化酶中CO与a3Fe和CuB的动态相互作用。
DOI：
10.1016/s0021-9258(19)68085-3
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
J. O. Alben
中科院分区：
文献类型：
--
作者：
F. G. Fiamingo;R. Altschuld;P. P. Moh;J. O. Alben
用傅里叶变换红外光谱法观察了一氧化碳在10 ~ 280 K之间、连续光解过程中和光解后与细胞色素c氧化酶的结合。与a3Fe结合的CO在1963 cm-1附近吸收，在较低频率处有较小的波段。低温光解作用下CO向CuB转移，主要组分在2062 cm-1附近，次要组分在2043 cm-1附近。通过与血红素和铜羰基的比较，所有波段的频率依赖于CO的同位素质量，以及主要和次要组分的相似行为与光解和弛豫动力学作为温度的函数来分配振动吸收。在210 K以下，a3FeCO光解后的重整是一个明显的一级过程，并具有速率常数分布。动力学可以用幂定律很好地描述。在140k ~ 180k范围内遵循Arrhenius行为，活化焓峰为40.3 kJ/mol，分布为g(H) = 2.56 kJ/mol（半最大值时全宽）。a3FeCO的主组分CO吸收带很窄（半最大值全宽= 2.4 cm-1），而CuBCO的主组分CO吸收带较宽（半最大值全宽= 6 cm-1）。这些数据表明，在还原的一氧化碳络合物中，a3FeCO处于高度有序的非极性环境中，与CuB充分分离，不受后者运动的干扰，而CuBCO处于较不有序的、更灵活的环境中。
Carbon monoxide bound to cytochrome c oxidase has been observed by Fourier transform infrared spectroscopy between 10 K and 280 K in the dark and during and after continuous photolysis. CO bound to a3Fe absorbs near 1963 cm-1, with minor bands at lower frequencies. Photolysis at low temperatures transfers CO to CuB, with the major component near 2062 cm-1 and a minor one near 2043 cm-1. Vibrational absorptions are assigned by comparison with heme and copper carbonyls, by frequency dependence of all bands on the isotopic mass of CO, and by similar behavior of major and minor components with photolysis and relaxation kinetics as a function of temperature. Reformation of a3FeCO after photolysis is an apparent first order process below 210 K with a distribution of rate constants. The kinetics are well described by a power law. Arrhenius behavior is followed between 140 K and 180 K to yield a peak activation enthalpy of 40.3 kJ/mol and a distribution in g(H) = 2.56 kJ/mol (full width at half-maximum). The major component of a3FeCO shows a very narrow CO absorption band (full width at half-maximum = 2.4 cm-1), while that of CuBCO shows a broader CO absorption (full width at half-maximum = 6 cm-1). These data indicate that in the reduced carbon monoxide complex, a3FeCO is in highly ordered nonpolar surroundings sufficiently separated from CuB that it is not perturbed by motion of the latter, while CuBCO is in less ordered, more flexible surroundings.
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组氨酸是细胞色素 c 氧化酶中细胞色素 α 3 的轴向配体。
DOI：
--
发表时间：
1981
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Stevens,TH;Chan,SI
通讯作者：
Chan,SI
来自 Soret 激发拉曼光谱的细胞色素氧化酶中细胞色素 α 和 α 3 的协调几何结构和振动特性。
影响因子：
2.9
作者：
Babcock,GT;Callahan,PM;Ondrias,MR;Salmeen,I
通讯作者：
Salmeen,I
细胞色素氧化酶的结构特点及反应机制：铁和铜X射线吸收精细结构。
影响因子：
3.4
作者：
Powers,L;Chance,B;Ching,Y;Angiolillo,P
通讯作者：
Angiolillo,P
影响因子：
2.9
作者：
BRUDVIG, GW;STEVENS, TH;CHAN, SI
通讯作者：
CHAN, SI