Electron transfer between azurin from Alcaligenes faecalis and cytochrome c551 from Pseudomonas aeruginosa.
Electron transfer between azurin from Alcaligenes faecalis and cytochrome c551 from Pseudomonas aeruginosa.
复制标题
来自粪产碱菌的天青蛋白和来自铜绿假单胞菌的细胞色素 c551 之间的电子转移。
DOI：
--
复制
发表时间：
1981
期刊：
影响因子：
--
通讯作者：
I. Pecht
中科院分区：
文献类型：
--
作者：
P. Rosen;M. Segal;I. Pecht
研究了粪产碱菌天青蛋白与铜绿假单胞菌细胞色素c551之间的电子转移平衡和动力学。平衡常数K =（[Cyt（III）] . [Az（I）]）/（[Cyt（II）]。[Az（II））]）= 0.5，比细胞色素c551之间观察到的小约7倍，并且滴定证实了产碱菌和假单胞菌天青蛋白的中点电位分别为+266 mV和+309 mV之间的43 mV差异。采用变温化学弛豫法研究了产碱杆菌天青蛋白与假单胞菌细胞色素c551的反应动力学。只有一个单一的松弛模式，观察到整个范围内的浓度和温度检查。因此，在铜绿假单胞菌天青蛋白和细胞色素c551之间的反应中观察到的慢弛豫时间在产碱杆菌天青蛋白中没有观察到。因此，可以归因于所研究的系统的最简单的机制是：[公式：见正文]。该方案类似于之前提出的铜绿假单胞菌天青蛋白和细胞色素c551之间的反应，但不涉及天青蛋白的构象转变。电子转移的比速率仍然很快：1.8 × 10（6）M-1。s-1和3.0 × 10（6）M-1。s-1。
The electron transfer equilibrium and kinetics between azurin from Alcaligenes faecalis and cytochrome c551 from Pseudomonas aeruginosa have been studied. The equilibrium constant K = ([Cyt(III)] . [Az(I)])/([Cyt(II)] . [Az(II))]) = 0.5 at 25 degrees C is about seven times smaller than that observed between the cytochrome c551 and the titrations confirmed a 43-mV difference between the mid-point potentials of +266 mV and +309 mV for the Alcaligenes and Pseudomonas azurins respectively. The kinetics of the reaction between Alcaligenes azurin and Pseudomonas cytochrome c551 were investigated by the temperature-jump chemical relaxation method. Only a single relaxation mode was observed throughout the range of concentrations and temperatures examined. Thus, the slow relaxation time observed in the reaction between P. aeruginosa azurin and cytochrome c551 is not observed with the Alcaligenes azurin. The simplest mechanism that can therefore be ascribed to the investigated system is: [formula: see text]. This scheme is similar to that proposed earlier for the reaction between P. aeruginosa azurin and cytochrome c551 but does not involve the conformational transition proposed for azurin. The specific rates for the electron transfer are still fast: 1.8 x 10(6) M-1 . s-1 and 3.0 x 10(6) M-1 . s-1 respectively at 25 degrees C.