细胞色素bc_1复合物的共振拉曼光谱

The resonance Raman spectra of pig heart cytochrome bc_1

对不同氧化还原状态的细胞色素 bc_1复合物的共振拉曼光谱进行了分析比较。对部分拉曼信号的变化进行了指认。细胞色素 c_1的还原引起1640cm^(_1)和1560cm^(_1)及1454cm^(_1)的明显变小,细胞色素 b 的还原引起1544cm^(_1)的下降。这些信号可以标志复合物中不同色素的氧化还原状态,对拉曼方法用于研究呼吸链酶系有重要参考价值。

Comparing the resonance Raman spectra of purified cytochrome bc_1 complex in different redox states of ^(+3)b_(566) ^(+3)b_(562) ^(+3)c_(11) ^(+3)b_(566) ^(+3)b_(562) ^(+2)c_(11) ^(+3)b_(566) ^(+3)b_(562) ^(+2)c_1 and ^(+2)b_(566) ^(+2)b(562)^(+3)c_(11) the following phenomena have been observed: 1.Whenthe state of ^(+3)b_(566) ^(+3)b_(562) ^(+3)c_1 turns to ^(+3)b_(566) ^(+3)b_(562) ^(+2)c_(11) the intensities of 1640cm^(-1) 1560cm^(-1) and 1454cm^(-1) decrease markedly and the inten- sity ratio of I_(1585)/I_(1544)inreversed.All these signals can he addressed to the change of cytochrome c_1. 2.When the state of ^(+3)b_(566) ^(+3)b_(562) ^(+3)c_1 turns to ^(+2)b_(566) ^(+2)b_(562) ^(+2)c_(11) the peak of 1544cm^(-1) decrease and 1585cm^(-1) shift to 1588cm^(-1) in addition to the change caused by cytochrome c_1 as mentioned above.Therefor 1544cm^(-1) can be a mark of cytochtome b. We hace also found the protein conformational change upon the redox states from the change of the intensity ratio of I_(846)/I_(832)which related to the enviroment of tyrosin.