Characterization of cytochrome b in the isolated ubiquinol‐cytochrome c 2 oxidoreductase from Rhodopseudomonas sphaeroides GA
Characterization of cytochrome b in the isolated ubiquinol‐cytochrome c
2 oxidoreductase from Rhodopseudomonas sphaeroides GA
复制标题
分离的泛醇细胞色素 c 中细胞色素 b 的表征
DOI：
10.1016/0014-5793(83)80136-7
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发表时间：
1983
期刊：
影响因子：
3.5
通讯作者：
G. Hauska
中科院分区：
文献类型：
--
作者：
N. Gabellini;G. Hauska
本文测定了红球藻细胞色素b_1复合物中细胞色素b_1带的消光系数。对于还原态和氧化态之间的差异，561 nm处的细胞色素带为25 mM− 1.cm − 1，553 nM处的细胞色素带为17.4 mM− 1.cm− 1。复合体中的细胞色素有两种形式。一种形式的Em7为50 mV，在液氮温度下α峰为557 nm，在室温下为561 nm，被抗霉素A红移。另一种形式的Em7为−90 mV，在液氮温度下在555和561 nm处有一个双α峰，对应于RT下的559和566 nm。这两种转变是相互独立的。两种细胞色素的中点电位均具有pH依赖性。红球藻和线粒体的细胞色素b1复合物的氧化还原中心组成是相同的。
Extinction coefficients for cytochromebandc1in the isolated cytochromebc1complex fromRhodopseudomonas sphaeroidesGA have been determined. They are 25 mM−1.cm−1at 561 nm for cytochromeband 17.4 mM−1.cm−1at 553 nM for cytochromec1for the difference between the reduced and the oxidized state. Cytochromebis present in two forms in the complex. One form has anEm7of 50 mV, an α-peak of 557 nm at liquid N2temperature and of 561 nm at RT, which is red-shifted by antimycin A. The other form has anEm7of −90 mV, a double α-peak of 555 and 561 nm at liquid N2temperature corresponding to 559 and 566 nm at RT. The absorption at 566 nm is red-shifted by myxothiazol. The two shifts are independent of each other. Both midpoint potentials of cytochromesbare pH-dependent. The redox center compositions of the cytochromebc1complexes fromRhodopseudomonas sphaeroidesand from mitochondria are identical.